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Sample records for lipase inhibitory activity

  1. Inhibitory activity of benzophenones from Anemarrhena asphodeloides on pancreatic lipase.

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    Jo, Yang Hee; Kim, Seon Beom; Ahn, Jong Hoon; Liu, Qing; Hwang, Bang Yeon; Lee, Mi Kyeong

    2013-04-01

    Pancreatic lipase is a key enzyme for lipid absorption by hydrolysis of total dietary fats. Therefore, inhibition of pancreatic lipase is suggested to be an effective therapy in the regulation of obesity. The EtOAc-soluble fraction of Anemarrhena asphodeloides rhizomes significantly inhibited pancreatic lipase activity as assessed using porcine pancreatic lipase as an in vitro assay system. Further fractionation of the EtOAc-soluble fraction of A. asphodeloides led to the isolation of a new benzophenone glycoside, zimoside A (1), together with the eleven known compounds iriflophenone (2), 2,4',6-trihydroxy-4-methoxybenzophenone (3), foliamangiferoside A (4), (2,3-dihydroxy-4-methoxyphenyl)(4-hydroxyphenyl)-methanone (5), 1,4,5,6,-tetrahydroxyxanthone (6), isosakuranetin (7), 4-hydroxybenzoic acid (8), 4-hydroxyacetophenone (9), vanillic acid (10), tyrosol (11) and 5-hydroxymethyl-2-furaldehyde (12). Among the isolated compounds, 3, 5 and 10 showed significant inhibition of pancreatic lipase activity.

  2. Lipase inhibitory activity of chlorophyll a, isofucosterol and saringosterol isolated from chloroform fraction of Sargassum thunbergii.

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    Kim, Koth-Bong-Woo-Ri; Kim, Min-Ji; Ahn, Dong-Hyun

    2014-01-01

    Three compounds (chlorophyll a, isofucosterol and saringosterol) were isolated from chloroform fraction of Sargassum thunbergii extract. The three compounds had two- to fourfold lower lipase inhibitory activity than that of the CHCl3:MeOH (C:M) (100:1) fraction (fraction I, 83.78% at 1 mg/mL). These results suggested that the high lipase inhibitory activity of fraction I was attributable to the actions of the three compounds. Therefore, S. thunbergii has potential for application as an anti-obesity agent.

  3. Pancreatic lipase inhibitory activity of taraxacum officinale in vitro and in vivo.

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    Zhang, Jian; Kang, Min-Jung; Kim, Myung-Jin; Kim, Mi-Eun; Song, Ji-Hyun; Lee, Young-Min; Kim, Jung-In

    2008-01-01

    Obesity has become a worldwide health problem. Orlistat, an inhibitor of pancreatic lipase, is currently approved as an anti-obesity drug. However, gastrointestinal side effects caused by Orlistat may limit its use. In this study the inhibitory activities of dandelion (Taraxacum officinale) against pancreatic lipase in vitro and in vivo were measured to determine its possible use as a natural anti-obesity agent. The inhibitory activities of the 95% ethanol extract of T. officinale and Orlistat were measured using 4-methylumbelliferyl oleate (4-MU oleate) as a substrate at concentrations of 250, 125, 100, 25, 12.5 and 4 microg/ml. To determine pancreatic lipase inhibitory activity in vivo, mice (n=16) were orally administered with corn oil emulsion (5 ml/kg) alone or with the 95% ethanol extract of T. officinale (400 mg/kg) following an overnight fast. Plasma triglyceride levels were measured at 0, 90, 180, and 240 min after treatment and incremental areas under the response curves (AUC) were calculated. The 95% ethanol extract of T. officinale and Orlistat, inhibited, porcine pancreatic lipase activity by 86.3% and 95.7% at a concentration of 250 microg/ml, respectively. T. officinale extract showed dose-dependent inhibition with the IC(50) of 78.2 microg/ml. A single oral dose of the extract significantly inhibited increases in plasma triglyceride levels at 90 and 180 min and reduced AUC of plasma triglyceride response curve (pofficinale exhibits inhibitory activities against pancreatic lipase in vitro and in vivo. Further studies to elucidate anti-obesity effects of chronic consumption of T. officinale and to identify the active components responsible for inhibitory activity against pancreatic lipase are necessary.

  4. A Bioactivity-Based Method for Screening, Identification of Lipase Inhibitors, and Clarifying the Effects of Processing Time on Lipase Inhibitory Activity of Polygonum Multiflorum

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    Yan-xu Chang

    2016-01-01

    Full Text Available Traditional Chinese medicine (TCM has been used for the treatment of many complex diseases. However, the bioactive components are always undefined. In this study, a bioactivity-based method was developed and validated to screen lipase inhibitors and evaluate the effects of processing on the lipase inhibitory activity of TCM by ultrahigh performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and fraction collector (UHPLC/Q-TOF-MS-FC. The results showed that both Polygonum multiflorum and processed P. multiflorum extracts had inhibitory effect against lipase with IC50 values of 38.84 μg/mL and 190.6 μg/mL, respectively. Stilbenes, phenolic acid, flavonoids, and anthraquinones were considered to be the potential lipase inhibitors. Eleven potential lipase inhibitors were simultaneously determined by UHPLC. Principal component analysis (PCA was employed in exploring the effects of processing time on lipase inhibitory activity of P. multiflorum. Compared with conventional methods, a bioactivity-based method could quantitatively analyze lipase inhibitory activity of individual constituent and provide the total lipase inhibitory activity of the samples. The results demonstrated that the activity integrated UHPLC/Q-TOF-MS-FC method was an effective and powerful tool for screening and identifying lipase inhibitors from traditional Chinese medicines.

  5. Inhibitory effect of morinda citrifolia L. On lipoprotein lipase activity.

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    Pak-Dek, M S; Abdul-Hamid, A; Osman, A; Soh, C S

    2008-10-01

    Efficacy of Morinda citrifolia L. leaf (MLE) and fruit extracts (MFE) in inhibiting lipoprotein lipase (LPL) was determined in vitro. The result of the study showed that the highest inhibition on the LPL activity was exhibited by MLE (66%+/- 2.1%), which is significantly higher than that demonstrated by MFE (54.5%+/- 2.5%), green tea extract (GTE) (54.5%+/- 2.6%), and catechin (43.6%+/- 6.1%). Percent of LPL inhibition increase with concentration of the extracts. Quantitative analysis of the extracts revealed the presence of high levels of (+)-catechin at 63.5 +/- 17 and 53.7 +/- 5.7 mg/g in MLE and MFE, respectively, although not as high as that found in GTE (530.6 +/- 42 mg/g). Appreciable amount of epicatechin was found in all extracts tested, while rutin was only found in MLE and MFE. The study suggested that both leaf and fruit of M. citrifolia may be used as antiobesity agents in body weight management.

  6. Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review

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    Atefehalsadat Seyedan

    2015-01-01

    Full Text Available Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity.

  7. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract.

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    Padilla-Camberos, Eduardo; Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos; Allen, Kirk

    2015-01-01

    Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

  8. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract

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    Eduardo Padilla-Camberos

    2015-01-01

    Full Text Available Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

  9. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract

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    Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos

    2015-01-01

    Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds. PMID:26078966

  10. Antioxidant and lipase inhibitory activities and essential oil composition of pomegranate peel extracts.

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    Hadrich, Fatma; Cher, Slim; Gargouri, Youssef Talel; Adel, Sayari

    2014-01-01

    The chemical composition of essential oil, antioxidant and pancreatic lipase inhibitory activities of various solvent extracts obtained from pomegranate peelTunisian cultivar was evaluated. Gas chromatography/mass spectrometry was used to determine the composition of the PP essential oil. Nine-teen components were identified and the main compounds were the camphor (60.32%) and the benzaldehyde (20.98%). The phenolic and flavonoids content varied from 0 to 290.10 mg Gallic acid equivalent and from 5.2 to 20.43 mg catechin equivalent/g dried extract. The antioxidant activity of various solvent extracts from pomegranate peel was also investigated using various in vitro assays as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method, β-carotene bleaching and reducing power assays.Methanol and ethanol extracts showed the most potent antioxidant activity in all assays tested followed by water and acetone extracts. The inhibitory effect of the pomegranate peelextracts on porcine pancreatic lipase was evaluated and the results showed that ethanol and methanol extracts markedly reduced lipase activity. Generally, the highestlipase activity inhibitory (100%) was observed at a concentration of 1 mg/ml after 30 min of incubation. LC-MS analysis of ethanol extract showed the presence of four components which are cholorogenic acid, mannogalloylhexoside, gallic acid and ellagic acid. Our findings demonstrate that the ethanol extract from pomegranate peel might be a good candidate for furtherinvestigations of new bioactive substances.

  11. Pancreatic lipase inhibitory activity of cassiamin A, a bianthraquinone from Cassia siamea.

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    Kumar, Dilip; Karmase, Aniket; Jagtap, Sneha; Shekhar, Ruchi; Bhutani, Kamlesh K

    2013-02-01

    In continuation towards the discovery of potential antiobesity lead(s) from natural products, we have screened n-hexane, dichloromethane (DCM), ethyl acetate (EtOAc) and methanol (MeOH) extracts of 33 Indian medicinal plants (200 extracts) for in vitro pancreatic lipase inhibitory activity. Of the screened extracts, the EtOAc extract of Cassia siamea roots showed 74.3 +/- 1.4% enzyme inhibition at 250 microg/mL concentration. Bioassay guided fractionation of the active extract afforded 6 known compounds viz. chrysophanol (1), physcion (2), emodin (3), cassiamin A (4), friedelin (5) and cycloart-25-en-3beta,24-diol (6). These compounds were further evaluated for pancreatic lipase inhibitory activity. Cassiamin A (4), a bianthraquinone, was found to be most active with an IC50 value of 41.8 +/- 1.2 microM and compounds 2 and 5 were found to be moderate enzyme inhibitors. Results indicate the antiobesity potential of C. siamea through pancreatic lipase inhibition.

  12. Studies of the in vitro cytotoxic, antioxidant, lipase inhibitory and antimicrobial activities of selected Thai medicinal plants

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    Kaewpiboon Chutima

    2012-11-01

    Full Text Available Abstract Background Traditional folk medicinal plants have recently become popular and are widely used for primary health care. Since Thailand has a great diversity of indigenous (medicinal plant species, this research investigated 52 traditionally used species of Thai medicinal plants for their in vitro cytotoxic, antioxidant, lipase inhibitory and antimicrobial activities. Methods The 55 dried samples, derived from the medicinally used parts of the 52 plant species were sequentially extracted by hexane, dichloromethane, ethanol and water. These 220 extracts were then screened for in vitro (i cytotoxicity against four cell lines, derived from human lung (A549, breast (MDA-MB-231, cervical (KB3-1 and colon (SW480 cancers, using the MTT cytotoxicity assay; (ii antioxidant activity, analyzed by measuring the scavenging activity of DPPH radicals; (iii lipase inhibitory activity, determined from the hydrolytic reaction of p-nitrophenyllaurate with pancreatic lipase; and (iv antimicrobial activity against three Gram-positive and two Gram-negative bacteria species plus one strain of yeast using the disc-diffusion method and determination of the minimum inhibitory concentration by the broth micro-dilution assay. Results The crude dichloromethane and/or ethanol extracts from four plant species showed an effective in vitro cytotoxic activity against the human cancer cell lines that was broadly similar to that of the specific chemotherapy drugs (etoposide, doxorubicin, vinblastine and oxaliplatin. In particular, this is the first report of the strong in vitro cytotoxic activity of Bauhinia strychnifolia vines. The tested tissue parts of only six plant species (Allium sativum, Cocoloba uvifera, Dolichandrone spathacea, Lumnitzera littorea, Sonneratia alba and Sonneratia caseolaris showed promising potential antioxidant activity, whereas lipase inhibitory activity was only found in the ethanol extract from Coscinum fenestratum and this was weak at 17-fold

  13. Zingiber cassumunar, Guazuma ulmifolia, and Murraya paniculata Extracts as Antiobesity: In Vitro Inhibitory Effect on Pancreatic Lipase Activity

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    DYAH ISWANTINI

    2011-03-01

    Full Text Available Zingiber cassumunar Roxb. (Bangle, Guazuma ulmifolia Lamk. (Jati belanda, and Murraya paniculata (Kemuning have been used as slimming agents in jamu. A few researches have performed studies on their potency as antiobesity. The aim of this research was to investigate the potency of Z. cassumunar rhizome, G. ulmifolia, and M. paniculata leaf extracts as antiobesity agent based on in vitro inhibition activity of the extracts on pancreatic lipase activity. In this research, water content determination, phytochemical assay, toxicity assay and in vitro assay of inhibition activity on pancreatic lipase were performed toward single and mixture extracts of Z. cassumunar, G. ulmifolia, and M. paniculata resulted by water, ethanol, and saponin extractions. The results indicated that 100 ppm of ethanol extraction of Z. cassumunar had highest inhibition effect on the activity of pancreatic lipase (29.17%, followed by 100 ppm of water extraction of M. paniculata (25.66%, 60 ppm of ethanol extraction of G. ulmifolia leaves (25.13% and ethanol extraction mixture of Z. cassumunar, G. ulmifolia, and M. paniculata leaves with ratio of 25:25:25 (21.58%. These inhibition effects were higher than inhibitory effect of 100 ppm of Xenical®/orlistat as the positive control, with the inhibition value of 17.53%. Saponin crude extracts had lower inhibitory effect than the other extractions. It was suggested that ethanol extraction of Z. cassumunar, and G. ulmifolia and water extraction of M. paniculata had potency as antiobesity agent.

  14. In Vitro Screening of Medicinal Plants Used in Mexico as Antidiabetics with Glucosidase and Lipase Inhibitory Activities

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    Guillermo Ramírez

    2012-01-01

    Full Text Available This work shows the inhibitory effect on glucosidase and lipase enzymes of 23 medicinal plants described as traditional treatments for diabetes in several Mexican sources. Hydroalcoholic extracts of selected plants were evaluated at 1 mg/mL for glucosidase and 0.25 mg/mL for lipase inhibitory activities, respectively. Camellia sinensis, acarbose, and orlistat were used as positive controls. Dose-response curves were done with the most active species. Sixty percent of all tested extracts inhibited more than 25% of α-glucosidase activity. C. sinensis displayed an inhibition of 85% (IC50 = 299 μg/mL, while Ludwigia octovalvis and Iostephane heterophylla showed the highest inhibition (82.7 %, IC50 = 202 μg/mL and 60.6%, CI50 = 509 μg/mL, resp.. With respect to lipase activity, L. octovalvis and Tecoma stans were the most inhibiting treatments (31.4%, IC50 = 288 μg/mL; 27.2%, IC50 = 320 μg/mL, while C. sinensis displayed 45% inhibition (IC50 = 310 μg/mL. These results indicate that a high proportion of plants used in Mexico as treatment for diabetes displays significant inhibition of these digestive enzymes.

  15. Pancreatic Lipase Inhibitory Effects of Mangosteen Pericarps

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    Xinjie Lin

    2014-03-01

    Full Text Available Pancreatic lipase plays a key role in the digestion and absorption of lipids, inhibition of Pancreatic Lipase (PL is considered as a new approach to obesity treatment. The objective of the present study was to find PL inhibitors from natural food sources. Eighteen natural food products sampled from local supermarkets in Zhuhai were tested for PL inhibitory activity using a copper-soap photometric method. Among the samples tested, the crude extracts from mangosteen pericarp, lemon pulp, celery, cucumber and dry longan were found to be able to suppress the PL activity to different extents, while dry red chili, fresh green chili and dry clove exhibited a promotion effect on the PL. Shiitake mushroom, green bell pepper, lemon peel and spices (ginger, oregano leaf, bay leaf, cinnamon and dry tangerine showed no significant influence either on the inhibition or promotion. The crude extract of mangosteen pericarp was further fractioned to trace active fractions. It was found that the n-butanol fraction was the major contributor to the PL-inhibitory effect of mangosteen pericarp and the inhibition rate was 43.9% at the concentration of 1 mg/mL, the IC50 value was 0.918 mg/mL. Mangosteen pericarp is worthy of utilization as functional food constituents for the prevention and treatment of obesity.

  16. In vitro inhibitory effect on pancreatic lipase activity of subfractions from ethanol extracts of fermented Oats (Avena sativa L.) and synergistic effect of three phenolic acids.

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    Cai, Shengbao; Wang, Ou; Wang, Mengqian; He, Jianfeng; Wang, Yong; Zhang, Di; Zhou, Feng; Ji, Baoping

    2012-07-25

    The purpose of the present work is to study the pancreatic lipase inhibitory effects of different subfractions (n-hexane, ethyl acetate (EA), n-butanol, and water) from ethanol extracts of nonfermented and fungi-fermented oats and to delineate the interactions of three primary phenolic acids in the EA subfractions. The EA subfraction showed the highest inhibitory effect on pancreatic lipase activity at 1.5 mg/mL compared to the other subfractions, regardless of whether the oats were fermented. Meanwhile, both of the EA subfractions of two fungi-fermented oats demonstrated more effective inhibitory activity than that of nonfermented oats. A positive correlation between the total phenolics content and inhibitory activity was found. The inhibitory ability of the EA subfraction from nonfermented or fermented oats also displayed a dose-dependent effect. The standards of caffeic, ferulic, and p-coumaric acids, mainly included in EA subfractions of fermented oats, also displayed a dose-dependent inhibitory effect. A synergistic effect of each binary combination of p-coumaric, ferulic, and caffeic acids was observed, especially at 150.0 μg/mL. Those results indicate that fungi-fermented oats have a more effective inhibitory ability on pancreatic lipase and polyphenols may be the most effective component and could be potentially used for dietary therapy of obesity.

  17. Chemical Constituents of Smilax china L. Stems and Their Inhibitory Activities against Glycation, Aldose Reductase, α-Glucosidase, and Lipase

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    Hee Eun Lee

    2017-03-01

    Full Text Available The search for natural inhibitors with anti-diabetes properties has gained increasing attention. Among four selected Smilacaceae family plants, Smilax china L. stems (SCS showed significant in vitro anti-glycation and rat lens aldose reductase inhibitory activities. Bioactivity-guided isolation was performed with SCS and four solvent fractions were obtained, which in turn yielded 10 compounds, including one phenolic acid, three chlorogenic acids, four flavonoids, one stilbene, and one phenylpropanoid glycoside; their structures were elucidated using nuclear magnetic resonance and mass spectrometry. All solvent fractions, isolated compounds, and stem extracts from plants sourced from six different provinces of South Korea were next tested for their inhibitory effects against advanced glycation end products, as well as aldose reductase. α-Glucosidase, and lipase assays were also performed on the fractions and compounds. Since compounds 3, 4, 6, and 8 appeared to be the superior inhibitors among the tested compounds, a comparative study was performed via high-performance liquid chromatography with photodiode array detection using a self-developed analysis method to confirm the relationship between the quantity and bioactivity of the compounds in each extract. The findings of this study demonstrate the potent therapeutic efficacy of SCS and its potential use as a cost-effective natural alternative medicine against type 2 diabetes and its complications.

  18. Phenolic antioxidants in some Vigna species of legumes and their distinct inhibitory effects on α-glucosidase and pancreatic lipase activities.

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    Sreerama, Yadahally N; Takahashi, Yoko; Yamaki, Kohji

    2012-09-01

    Phenolic extracts of 4 Vigna species of legumes (mung bean, moth bean, and black and red varieties of adzuki beans) were evaluated for phenolic contents, antioxidant activities, and inhibitory properties against α-glucosidase and pancreatic lipase. Results showed that adzuki bean varieties contain higher phenolic indexes than mung bean and moth beans. Adzuki bean (black) variety was found to be the most active 2,2'-diphenyl-1-picrylhydrazyl and superoxide anion scavenger. However, the hydrogen peroxide scavenging and metal chelating abilities were significantly higher in adzuki bean (red) variety. Mung bean exhibited least antioxidant activities in all the methods tested. Phenolic extracts from these legumes also showed distinct variations in the inhibition of enzymes associated with hyperglycemia and hyperlipidemia. Inhibitory activities of all the extracts against lipase were found to be more potent than α-glucosidase. Although, α-glucosidase inhibitory activity was superior in the black variety of adzuki bean (IC(50,) 26.28 mg/mL), both adzuki bean varieties (black and red) along with moth bean showed strong inhibitory activities on lipase with no significant difference in their IC(50) values (7.32 to 9.85 mg/mL). These results suggest that Vigna species of legumes are potential source of antioxidant phenolics and also great sources of strong natural inhibitors for α-glucosidase and lipase activities. This information may help for effective utilization of these legumes as functional food ingredients for promoting health. Practical Application:  Vigna species of legumes are good sources of phenolic antioxidants and strong natural inhibitors of enzymes associated with diabetes and obesity. Therefore, utilization of these legumes in the development of functional foods with increased therapeutic value would be a significant step toward health promotion and wellness.

  19. Apple peels, from seven cultivars, have lipase-inhibitory activity and contain numerous ursenoic acids as identified by LC-ESI-QTOF-HRMS.

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    McGhie, Tony K; Hudault, Sébastien; Lunken, Rona C M; Christeller, John T

    2012-01-11

    Apple peel contains numerous phytochemicals, many of which show bioactivity. This study investigated the identity of triterpenoid compounds contained in ethanolic extracts of peel from seven apple cultivars. Using HPLC-ESI-QTOF-HRMS, accurate mass information was obtained for 43 compounds, and chemical identity was inferred from the calculated elemental composition, fragment masses, ms/ms, and a limited set of authentic standards. Compounds were identified as triterpene acids and tentatively identified as ursenoic (or oleanoic) acid derivatives containing hydroxyl, oxo, and coumaroyloxy groups. These apple skin extracts exhibited lipase-inhibitory activity, which may be linked to the ursenoic acid content. Furthermore, both triterpene content and lipase-inhibitory activity varied by cultivar.

  20. In vitro pancreatic lipase, cholesterol esterase and cholesterol micellization inhibitory activity of Sri Lankan low grown orthodox Orange Pekoe grade black tea (Camellia sinensis L.

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    Wanigasekera Daya Ratnasooriya

    2015-07-01

    Full Text Available Objective: To access the pancreatic lipase, cholesterol esterase and cholesterol micellization inhibitory activities of Sri Lankan low grown orthodox Orange Pekoe grade black tea made from uppermost tender leaves and unopened buds of Camellia sinensis L. Methods: Black tea brew (BTB was made according to International Organization for Standardization 3103 specifications and concentrations of BTB tested were 37.5, 75.0, 150.0, 300.0 and 600.0 µg/mL for antilipase and anti-cholesterol esterase assays and 0.25, 0.50 and 1.00 µg/mL for cholesterol micellization inhibitory assay. Results: The results showed that BTB of Sri Lankan low grown orthodox Orange Pekoe grade black tea has marked and dose-dependent (r 2 = 0.95 cholesterol micellization inhibitory activity in vitro comparable to epigallocatechin gallate, the reference drug used. In contrast, BTB had only mild but dose-dependent (r 2 = 0.94 inhibitory activity against pancreatic lipase and weak inhibitory effect (up to 13.17% on pancreatic cholesterol esterase. Conclusions: It is concluded that consumption of BTB of Sri Lankan low grown orthodox Orange Pekoe grade tea as a beverage may be a useful strategy in the management of hyperlipidaemia.

  1. In vitro pancreatic lipase, cholesterol esterase and cholesterol micellization inhibitory activity of Sri Lankan low grown orthodox Orange Pekoe grade black tea (Camellia sinensis L.)

    Institute of Scientific and Technical Information of China (English)

    Wanigasekera Daya Ratnasooriya

    2015-01-01

    Objective:To access the pancreatic lipase, cholesterol esterase and cholesterol micellization inhibitory activities of Sri Lankan low grown orthodox Orange Pekoe grade black tea made from uppermost tender leaves and unopened buds ofCamellia sinensis L. Methods: Black tea brew (BTB) was made according to International Organization for Standardization 3103 specifications and concentrations ofBTB tested were 37.5, 75.0, 150.0, 300.0 and 600.0µg/mL for antilipase and anti-cholesterol esterase assays and 0.25, 0.50 and 1.00µg/mL for cholesterol micellization inhibitory assay. Results:The results showed thatBTB of Sri Lankan low grown orthodox Orange Pekoe grade black tea has marked and dose-dependent (r2 = 0.95) cholesterol micellization inhibitory activityin vitro comparable to epigallocatechin gallate, the reference drug used. In contrast, BTB had only mild but dose-dependent (r2= 0.94) inhibitory activity against pancreatic lipase and weak inhibitory effect (up to 13.17%) on pancreatic cholesterol esterase. Conclusions: It is concluded that consumption ofBTB of Sri Lankan low grown orthodox Orange Pekoe grade tea as a beverage may be a useful strategy in the management of hyperlipidaemia.

  2. In vitro investigation of the potential health benefits of wild Mediterranean dietary plants as anti-obesity agents with α-amylase and pancreatic lipase inhibitory activities.

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    Marrelli, Mariangela; Loizzo, Monica Rosa; Nicoletti, Marcello; Menichini, Francesco; Conforti, Filomena

    2014-08-01

    Inhibition of digestive enzymes is one of the most widely studied mechanisms used to determine the potential efficacy of natural products as anti-obesity agents. In vitro studies reported here were performed to evaluate the inhibitory activity of formulations of edible plants from Italy on amylase and lipase by monitoring the hydrolysis of nitrophenyl caprilate and the hydrolysis of glycoside bonds in digestible carbohydrate foods. The formulation obtained from Capparis sicula exhibited the strongest inhibitory effect on pancreatic lipase (IC50 = 0.53 mg mL(-1) ) while the Borago officinalis formulation exhibited the strongest inhibitory effect on α-amylase (IC50 = 31.61 µg mL(-1) ). In order to characterise the extracts, high-performance thin-layer chromatography analysis of the formulations was performed, revealing the predominance of (±)-catechin in Mentha aquatica formulation, rutin in C. sicula, and caffeic acid and chlorogenic acid in Echium vulgare. The results obtained indicated that the extracts of C. sicula and B. officinalis could be good candidates for further studies to isolate pancreatic lipase and α-amylase inhibitors, respectively. © 2013 Society of Chemical Industry.

  3. Inhibitory activity of chlorogenic acids in decaffeinated green coffee beans against porcine pancreas lipase and effect of a decaffeinated green coffee bean extract on an emulsion of olive oil.

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    Narita, Yusaku; Iwai, Kazuya; Fukunaga, Taiji; Nakagiri, Osamu

    2012-01-01

    A decaffeinated green coffee bean extract (DGCBE) inhibited porcine pancreas lipase (PPL) activity with an IC50 value of 1.98 mg/mL. Six different chlorogenic acids in DGCBE contributed to this PPL inhibition, accounting for 91.8% of the inhibitory activity. DGCBE increased the droplet size and decreased the specific surface area of an olive oil emulsion.

  4. Comparison of pancreatic lipase inhibitory isoflavonoids from unripe and ripe fruits of Cudrania tricuspidata

    Science.gov (United States)

    Jo, Yang Hee; Kim, Seon Beom; Liu, Qing; Do, Seon-Gil; Hwang, Bang Yeon

    2017-01-01

    The composition and content of the active constituents and their biological activity vary according to diverse factors including their maturation stages. A previous study showed that the fruits of Cudrania tricuspidata inhibited pancreatic lipase activity, a key enzyme in fat absorption. In this study, we investigated the chemical composition and pancreatic lipase inhibitory activity of unripe and ripe fruits of C. tricuspidata. Unripe fruits of C. tricuspidata have a higher content of total phenolic and flavonoids and exhibited stronger pancreatic lipase inhibition compared to ripe fruits. HPLC analysis revealed the different chemical compositions of the unripe and ripe fruits. Further fractionation resulted in the isolation of 30 compounds including two new isoflavonoids. Analysis of the chemical constituents of the unripe and ripe fruits revealed that a 2,2-dimethylpyran ring, a cyclized prenyl, was the predominant side chain in the unripe fruits, whereas it was a linear prenyl group in the ripe fruits. In addition, a new isoflavonoid (19) from the unripe fruits showed the most potent inhibition on pancreatic lipase. Taken together, the maturation stage is an important factor for maximum efficacy and that unripe fruits of C. tricuspidata are a good source of new bioactive constituents for the regulation of obesity PMID:28253267

  5. Inhibitory effects of oolong tea polyphenols on pancreatic lipase in vitro.

    Science.gov (United States)

    Nakai, Masaaki; Fukui, Yuko; Asami, Sumio; Toyoda-Ono, Yoshiko; Iwashita, Takashi; Shibata, Hiroshi; Mitsunaga, Tohru; Hashimoto, Fumio; Kiso, Yoshinobu

    2005-06-01

    Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition.

  6. In vitro prevention of chick pancreatic lipase activity by Abroma augusta extract

    Institute of Scientific and Technical Information of China (English)

    Nidhi Gupta; Aditya Ganeshpurkar; Nishikant Jatav; Divya Bansal; Nazneen Dubey

    2012-01-01

    Objective: To investigate chick pancreatic lipase inhibitory activities of the Abroma augusta (A. augusta). Methods: A. augusta was first extracted with methanol and subjected to phytochemical screenings. Quantitative estimation of flavonoids, phenolics and alkaloids was done. Pancreatic lipase from chick pancreas was isolated and used as substrate for anti-lipase studies. Results:A. augusta extract effectively inhibited concentration dependent lipase activity, whereby extract at concentration 100 μg/mL inhibited 88.6% enzyme activity. Conclusions: From these results, it could be concluded that A. augusta can be used as a potential source anti-lipase agents.

  7. Inhibitory effects of chickpea and Tribulus terrestris on lipase, α-amylase and α-glucosidase.

    Science.gov (United States)

    Ercan, Pınar; El, Sedef Nehir

    2016-08-15

    The total saponin content and its in vitro bioaccessibilities in Tribulus terrestris and chickpea were determined by a static in vitro digestion method (COST FA1005 Action INFOGEST). Also, in vitro inhibitory effects of the chosen food samples on lipid and starch digestive enzymes were determined by evaluating the lipase, α-amylase and α-glucosidase activities. The tested T. terrestris and chickpea showed inhibitory activity against α-glucosidase (IC50 6967 ± 343 and 2885 ± 85.4 μg/ml, respectively) and α-amylase (IC50 343 ± 26.2 and 167 ± 6.12 μg/ml, respectively). The inhibitory activities of T. terrestris and chickpea against lipase were 15.3 ± 2.03 and 9.74 ± 1.09 μg/ml, respectively. The present study provides the first evidence that these food samples (T. terrestris, chickpea) are potent inhibitors of key enzymes in digestion of carbohydrates and lipids in vitro.

  8. Lipase and protease extraction from activated sludge

    DEFF Research Database (Denmark)

    Gessesse, Amare; Dueholm, Thomas; Petersen, Steffen B.

    2003-01-01

    of gentle and efficient enzyme extraction methods from environmental samples is very important. In this study we present a method for the extraction of lipases and proteases from activated sludge using the non-ionic detergent Triton X-100, EDTA, and cation exchange resin (CER), alone or in combination...... for the extraction of lipases and proteases from activated sludge. The sludge was continuously stirred in the presence of either buffer alone or in the presence of detergent and/or chelating agents. In all cases, a marked reduction in floc size was observed upon continuous stirring. However, no lipase activity...... and negligible protease activity was extracted in the presence of buffer alone, indicating that enzyme extraction was not due to shear force alone. The highest lipase activity was extracted using 0.1% Triton X-100 above which the activity was gradually decreasing. For proteases, the highest activity was obtained...

  9. Comparison of α-amylase, α-glucosidase and lipase inhibitory activity of the phenolic substances in two black legumes of different genera.

    Science.gov (United States)

    Tan, Yuqing; Chang, Sam K C; Zhang, Yan

    2017-01-01

    Antioxidant-rich plant foods can inhibit starch and lipid digestions that are relevant to diabetes management. Two high-antioxidant black legumes, black soybean (Glycine max) and black turtle bean (Phaseolus vulgaris), belonging to two different genera were used to investigate their capacity against digestive enzymes. Phenolic substances were compared in crude, semi-purified extracts (semi-purified by XAD-7 column), and fractions (fractionationed by Sephadex LH-20 column) from these two legumes. In addition, their antioxidant capacities and abilities to inhibit digestive enzymes were characterized. Results showed that Fraction V from black soybean was the most effective (IC50: 0.25mg/mL) against α-amylase; Fraction V from black turtle bean was the most potent (IC50: 0.25μg/mL) against α-glucosidase; Fraction IV from black turtle bean was the most powerful (IC50: 76μg/mL) against lipase. Of the pure phenolic compounds tested, myricetin showed the highest inhibition of α-amylase, α-glucosidase and lipase (IC50: 0.38mg/mL, 0.87μg/mL and 15μg/mL, respectively).

  10. Screening of lipase inhibitors from Scutellaria baicalensis extract using lipase immobilized on magnetic nanoparticles and study on the inhibitory mechanism.

    Science.gov (United States)

    Wan, Li-Hong; Jiang, Xiao-Lan; Liu, Yi-Ming; Hu, Jin-Jie; Liang, Jian; Liao, Xun

    2016-03-01

    Scutellaria baicalensis is a traditional Chinese medicinal plant possessing a wide variety of biological activities. In this work, lipase immobilized on magnetic nanoparticles (LMNPs) was used as solid phase extract absorbent for screening of lipase inhibitors from this plant. Three flavonoids were found to bind to LMNPs and were identified as baicalin, wogonin, and oroxylin A by liquid chromatography-mass spectrometry (HPLC-MS). Their IC50 values were determined to be 229.22 ± 12.67, 153.71 ± 9.21, and 56.07 ± 4.90 μM, respectively. Fluorescence spectroscopy and molecular docking were used to probe the interactions between these flavonoids and lipase. All the flavonoids quenched the fluorescence of lipase statically by forming new complexes, implying their affinities with the enzyme. The thermodynamic analysis suggested that van der Waals force and hydrogen bond were the main forces between wogonin and lipase, while hydrophobic force was the main force for the other two flavonoids. The results from a molecular docking study further revealed that all of them could insert into the pocket of lipase binding to a couple of amino acid residues.

  11. The modulation of pancreatic lipase activity by alginates

    OpenAIRE

    Wilcox, Matthew D.; Brownlee, Iain A.; Richardson, J. Craig; Dettmar, Peter W.; Jeffrey P. Pearson

    2014-01-01

    Alginates are comprised of mannuronic (M) and guluronic acid (G) and have been shown to inhibit enzyme activity. Pancreatic lipase is important in dietary triacylglycerol breakdown; reducing pancreatic lipase activity would reduce triacylglycerol breakdown resulting in lower amounts being absorbed by the body. Lipase activity in the presence of biopolymers was assessed by enzymatic assay using natural and synthetic substrates. Alginate inhibited pancreatic lipase by a maximum of 72.2% (±4.1) ...

  12. Parathyroid hormone is not an inhibitor of lipoprotein lipase activity.

    Science.gov (United States)

    Arnadottir, M; Nilsson-Ehle, P

    1994-01-01

    The reduced lipoprotein lipase (LPL) activities in uraemia are reflected by increased serum triglyceride concentrations and reduced HDL cholesterol concentrations. Both hyperparathyroidism and circulating inhibitor(s) of LPL have been associated with the disturbances of lipid metabolism in uraemia. The aim of the present study was to investigate if parathyroid hormone (PTH) had an inhibitory effect on LPL activity. Plasma post-heparin LPL activities, plasma LPL inhibitory activities, serum PTHintact and serum PTHC-terminal concentrations were analysed in 20 patients on haemodialysis and 20 healthy controls. The effects of purified, human PTHintact and a carboxyterminal fragment of PTH (PTH39-84) on LPL activities in post-heparin plasma from healthy individuals and on the enzyme activity of purified, bovine milk LPL, activated with apolipoprotein CII, were studied. Patients had significantly higher plasma LPL inhibitory activities than controls, but there was no correlation between plasma LPL inhibitory activities and serum PTH concentrations. Neither PTHintact nor PTH39-84 had a significant effect on LPL activities in vitro. Thus there was no evidence of a direct inhibition of LPL activity by PTH under the present in-vivo or in-vitro conditions.

  13. The Inhibition of Lipase and Glucosidase Activities by Acacia Polyphenol

    Directory of Open Access Journals (Sweden)

    Nobutomo Ikarashi

    2011-01-01

    Full Text Available Acacia polyphenol (AP extracted from the bark of the black wattle tree (Acacia mearnsii is rich in unique catechin-like flavan-3-ols, such as robinetinidol and fisetinidol. In an in vitro study, we measured the inhibitory activity of AP on lipase and glucosidase. In addition, we evaluated the effects of AP on absorption of orally administered olive oil, glucose, maltose, sucrose and starch solution in mice. We found that AP concentration-dependently inhibited the activity of lipase, maltase and sucrase with an IC50 of 0.95, 0.22 and 0.60 mg ml−1, respectively. In ICR mice, olive oil was administered orally immediately after oral administration of AP solution, and plasma triglyceride concentration was measured. We found that AP significantly inhibited the rise in plasma triglyceride concentration after olive oil loading. AP also significantly inhibited the rise in plasma glucose concentration after maltose and sucrose loading, and this effect was more potent against maltose. AP also inhibited the rise in plasma glucose concentration after glucose loading and slightly inhibited it after starch loading. Our results suggest that AP inhibits lipase and glucosidase activities, which leads to a reduction in the intestinal absorption of lipids and carbohydrates.

  14. Lipase and protease extraction from activated sludge

    DEFF Research Database (Denmark)

    Gessesse, Amare; Dueholm, Thomas; Petersen, Steffen B.

    2003-01-01

    In the process of wastewater treatment hydrolysis of polymeric substances is the first and rate-limiting step. A closer study of the enzymes catalysing these reactions is essential for a better understanding of the microbial activity in the wastewater treatment process. Therefore, development...... of gentle and efficient enzyme extraction methods from environmental samples is very important. In this study we present a method for the extraction of lipases and proteases from activated sludge using the non-ionic detergent Triton X-100, EDTA, and cation exchange resin (CER), alone or in combination...... and negligible protease activity was extracted in the presence of buffer alone, indicating that enzyme extraction was not due to shear force alone. The highest lipase activity was extracted using 0.1% Triton X-100 above which the activity was gradually decreasing. For proteases, the highest activity was obtained...

  15. LIPOLYTIC ACTIVITY IN THE BLOOD AFTER LIPASE INGESTION,

    Science.gov (United States)

    The nature of the enzyme appearing in the blood after oral ingestion of pancreatic lipase has been studied by determining the effect of the presence...bile acid while the enzymic activity of both pancreatic lipase and the enzyme present in the blood after pancreatic lipase ingestion were greatly...enhanced by the presence of cholic acid. Although the rate of fat absorption has been shown to be affected by lipase ingestion , the possibility remains

  16. Effects of dietary fibers and cholestyramine on the activity of pancreatic lipase in vitro.

    Science.gov (United States)

    Lairon, D; Lafont, H; Vigne, J L; Nalbone, G; Léonardi, J; Hauton, J C

    1985-10-01

    Most experiments were conducted in the presence of human gallbladder bile; colipase and pancreatic lipase were purified using porcine pancreas. The adsorption of bile salts, phospholipids and cholesterol from the bile, together with that of pancreatic lipase was measured on wheat bran, cellulose, hemicellulose (xylan), slightly methylated pectin (42%) and cholestyramine. In contrast to cholestyramine which intensively binds biliary lipids (61.7-81.7%) and pancreatic lipase (47.5%), the fibers studied only had a low adsorbent power. The direct influence of these fibers and of cholestyramine at concentrations ranging from 0-5% on lipase activity was measured at constant pH, using two conventional assay systems, long chain triglycerides and tributyrin. In the presence of human bile and colipase, a drastic reduction in triglyceride hydrolysis by lipase was observed with cholestyramine (loss of 66-82%) and wheat bran (loss of 77-94%) at 1% concentration. The other fibers did not have any marked effects on enzyme activity. The use of a radio labeled lipase made it possible to demonstrate that the inhibitory effect of bran on enzyme activity was independent of adsorption phenomena on bran. The fraction of bran that can be solubilized in the aqueous phase, in fact, induced this reduction in activity. The presence of protein inhibitor in bran may be responsible for the reduction in pancreatic lipase activity.

  17. Polyphenols extracted from black tea (Camellia sinensis) residue by hot-compressed water and their inhibitory effect on pancreatic lipase in vitro.

    Science.gov (United States)

    Yuda, Naoki; Tanaka, Miyuki; Suzuki, Manabu; Asano, Yuzo; Ochi, Hiroshi; Iwatsuki, Keiji

    2012-12-01

    Polyphenols, retained in black tea wastes following the commercial production of tea beverages, represent an underutilized resource. The purpose of this study was to investigate the potential use of hot-compressed water (HCW) for the extraction of pancreatic lipase-inhibiting polyphenols from black tea residues. Black tea residues were treated with HCW at 10 °C intervals, from 100 to 200 °C. The resulting extracts were analyzed using high-performance liquid chromatography-mass spectrometry and assayed to determine their inhibitory effect on pancreatic lipase activity in vitro. Four theaflavins (TF), 5 catechins, 2 quercetin glycosides, quinic acid, gallic acid, and caffeine were identified. The total polyphenol content of extracts increased with increasing temperature but lipase inhibitors (TF, theaflavin 3-O-gallate, theaflavin 3'-O-gallate, theaflavin 3,3'-O-gallate, epigallocatechin gallate, and epicatechin gallate) decreased over 150 °C. All extracts inhibited pancreatic lipase but extracts obtained at 100 to 140 °C showed the greatest lipase inhibition (IC(50) s of 0.9 to 1.3 μg/mL), consistent with the optimal extraction of TFs and catechins except catechin by HCW between 130 and 150 °C. HCW can be used to extract pancreatic lipase-inhibiting polyphenols from black tea waste. These extracts have potential uses, as dietary supplements and medications, for the prevention and treatment of obesity.

  18. Porcine Pancreatic Lipase Inhibitory Agent Isolated from Medicinal Herb and Inhibition Kinetics of Extracts from Eleusine indica (L. Gaertner

    Directory of Open Access Journals (Sweden)

    Siew Ling Ong

    2016-01-01

    Full Text Available Eleusine indica (Linnaeus Gaertner is a traditional herb known to be depurative, febrifuge, and diuretic and has been reported with the highest inhibitory activity against porcine pancreatic lipase (PPL among thirty two plants screened in an earlier study. This study aims to isolate and identify the active components that may possess high potential as an antiobesity agent. Of the screened solvent fractions of E. indica, hexane fraction showed the highest inhibitory activity of 27.01±5.68% at 100 μg/mL. Bioactivity-guided isolation afforded three compounds from the hexane fraction of E. indica, namely, β-sitosterol, stigmasterol, and lutein. The structures of these compounds were elucidated using spectral techniques. Lutein showed an outstanding inhibitory activity against PPL (55.98±1.04%, with activity 60% higher than that of the reference drug Orlistat. The other compounds isolated and identified were β-sitosterol (2.99±0.80% and stigmasterol (2.68±0.38%. The enzyme kinetics of E. indica crude methanolic extract on PPL showed mixed inhibition mechanism.

  19. Porcine Pancreatic Lipase Inhibitory Agent Isolated from Medicinal Herb and Inhibition Kinetics of Extracts from Eleusine indica (L.) Gaertner

    Science.gov (United States)

    Ong, Siew Ling

    2016-01-01

    Eleusine indica (Linnaeus) Gaertner is a traditional herb known to be depurative, febrifuge, and diuretic and has been reported with the highest inhibitory activity against porcine pancreatic lipase (PPL) among thirty two plants screened in an earlier study. This study aims to isolate and identify the active components that may possess high potential as an antiobesity agent. Of the screened solvent fractions of E. indica, hexane fraction showed the highest inhibitory activity of 27.01 ± 5.68% at 100 μg/mL. Bioactivity-guided isolation afforded three compounds from the hexane fraction of E. indica, namely, β-sitosterol, stigmasterol, and lutein. The structures of these compounds were elucidated using spectral techniques. Lutein showed an outstanding inhibitory activity against PPL (55.98 ± 1.04%), with activity 60% higher than that of the reference drug Orlistat. The other compounds isolated and identified were β-sitosterol (2.99 ± 0.80%) and stigmasterol (2.68 ± 0.38%). The enzyme kinetics of E. indica crude methanolic extract on PPL showed mixed inhibition mechanism. PMID:27872792

  20. Surfactant-activated lipase hybrid nanoflowers with enhanced enzymatic performance

    Science.gov (United States)

    Cui, Jiandong; Zhao, Yamin; Liu, Ronglin; Zhong, Cheng; Jia, Shiru

    2016-01-01

    Increasing numbers of materials have been extensively used as platforms for enzyme immobilization to improve catalytic performance. However, activity of the most of the enzymes was declined after immobilization. Here, we develop a surfactant-activated lipase-inorganic flowerlike hybrid nanomaterials with rational design based on interfacial activation and self-assembly. The resulting surfactant-activated lipase-inorganic hybird nanoflower (activated hNF-lipase) exhibited 460% and 200% higher activity than native lipase and conventional lipase-inorganic hybird nanoflower (hNF-lipase). Furthermore, the activated hNF-lipase displayed good reusability due to its monodispersity and mechanical properties, and had excellent long-time stability. The superior catalytic performances were attributed to both the conformational modulation of surfactants and hierarchical structure of nanoflowers, which not only anchored lipases in an active form, but also decreased the enzyme-support negative interaction and mass-transfer limitations. This new biocatalytic system is promising to find widespread use in applications related to biomedicine, biosensor, and biodiesel. PMID:27297609

  1. Diet quality determines lipase gene expression and lipase/esterase activity in Daphnia pulex

    Directory of Open Access Journals (Sweden)

    Apostolos-Manuel Koussoroplis

    2017-02-01

    Full Text Available We studied the short- (12 h and long-term (144 h response of Daphnia pulex lipases to quality shifts in diets consisting of different mixtures of the green alga Scenedesmus with the cyanobacterium Synechococcus, two species with contrasting lipid compositions. The lipase/esterase activity in both the gut and the body tissues had fast responses to the diet shift and increased with higher dietary contributions of Synechococcus. When screening the Daphnia genome for TAG lipases, we discovered a large gene-family expansion of these enzymes. We used a subset of eight genes for mRNA expression analyses and distinguished between influences of time and diet on the observed gene expression patterns. We identified five diet-responsive lipases of which three showed a sophisticated short- and long-term pattern of expression in response to small changes in food-quality. Furthermore, the gene expression of one of the lipases was strongly correlated to lipase/esterase activity in the gut suggesting its potentially major role in digestion. These findings demonstrate that the lipid-related enzymatic machinery of D. pulex is finely tuned to diet and might constitute an important mechanism of physiological adaptation in nutritionally complex environments.

  2. Porcine pancreatic lipase related protein 2 has high triglyceride lipase activity in the absence of colipase.

    Science.gov (United States)

    Xiao, Xunjun; Ross, Leah E; Sevilla, Wednesday A; Wang, Yan; Lowe, Mark E

    2013-09-01

    Efficient dietary fat digestion is essential for newborns who consume more dietary fat per body weight than at any other time of life. In many mammalian newborns, pancreatic lipase related protein 2 (PLRP2) is the predominant duodenal lipase. Pigs may be an exception since PLRP2 expression has been documented in the intestine but not in the pancreas. Because of the differences in tissue-specific expression, we hypothesized that the kinetic properties of porcine PLRP2 would differ from those of other mammals. To characterize its properties, recombinant porcine PLRP2 was expressed in HEK293T cells and purified to homogeneity. Porcine PLRP2 had activity against tributyrin, trioctanoin and triolein. The activity was not inhibited by bile salts and colipase, which is required for the activity of pancreatic triglyceride lipase (PTL), minimally stimulated PLRP2 activity. Similar to PLRP2 from other species, PLRP2 from pigs had activity against galactolipids and phospholipids. Importantly, porcine PLRP2 hydrolyzed a variety of dietary substrates including pasteurized human mother's milk and infant formula and its activity was comparable to that of PTL. In conclusion, porcine PLRP2 has broad substrate specificity and has high triglyceride lipase activity even in the absence of colipase. The data suggest that porcine PLRP2 would be a suitable lipase for inclusion in recombinant preparations for pancreatic enzyme replacement therapy.

  3. Lipase Activity in Fermented Oil Seeds of Africa Locust Bean ...

    African Journals Online (AJOL)

    acer

    Castor Seeds (Ricinu Communis) and African Oil Bean (Pentaclethra Macrophylla). A.A. Liman*, P. ... The peak lipase activity for fermented Africa locust bean, Castor seed, and African oil bean were ..... fermented vegetable proteins. World.

  4. The modulation of pancreatic lipase activity by alginates.

    Science.gov (United States)

    Wilcox, Matthew D; Brownlee, Iain A; Richardson, J Craig; Dettmar, Peter W; Pearson, Jeffrey P

    2014-03-01

    Alginates are comprised of mannuronic (M) and guluronic acid (G) and have been shown to inhibit enzyme activity. Pancreatic lipase is important in dietary triacylglycerol breakdown; reducing pancreatic lipase activity would reduce triacylglycerol breakdown resulting in lower amounts being absorbed by the body. Lipase activity in the presence of biopolymers was assessed by enzymatic assay using natural and synthetic substrates. Alginate inhibited pancreatic lipase by a maximum of 72.2% (±4.1) with synthetic substrate (DGGR) and 58.0% (±9.7) with natural substrate. High-G alginates from Laminaria hyperborea seaweed inhibited pancreatic lipase to a significantly higher degree than High-M alginates from Lessonia nigrescens, showing that inhibition was related to alginate structure. High-G alginates are effective inhibitors of pancreatic lipase and are used in the food industry at low levels. They could be included at higher levels in foods without altering organoleptic qualities, potentially reduce the uptake of dietary triacylglycerol aiding in weight management.

  5. Lipase Activity among Bacteria Isolated from Amazonian Soils

    Directory of Open Access Journals (Sweden)

    André Luis Willerding

    2011-01-01

    Full Text Available The objective of this study was to select lipase-producing bacteria collected from different counties of the Amazon region. Of the 440 bacteria strains, 181 were selected for the lipase assay in qualitative tests at Petri dishes, being 75 (41% lipase positive. The enzymatic index was determined during fifteen days at different temperatures (30°, 35°, 40°, and 45°C. The highest lipase activity was observed within 72 hours at 30°C. Twelve bacteria strains presented an index equal to or greater than the standard used like reference, demonstrating the potential of microbial resource. After the bioassay in Petri dishes, the selected bacteria strains were analyzed in quantitative tests on p-nitrophenyl palmitate (p-NPP. A group of the strains was selected for other phases of study with the use in oleaginous substrates of the Amazonian flora, aiming for the application in processes like oil biotransformation.

  6. Study of Antiobesity Effect through Inhibition of Pancreatic Lipase Activity of Diospyros kaki Fruit and Citrus unshiu Peel

    Science.gov (United States)

    Kim, Gyo-Nam; Shin, Mi-Rae; Shin, Sung Ho; Lee, Ah Reum; Lee, Joo Young; Seo, Bu-Il; Kim, Min Yeong; Kim, Tae Hoon; Noh, Jeong Sook; Rhee, Man Hee

    2016-01-01

    Pancreatic lipase is the enzyme responsible for digestion and absorption of triglycerides, being its inhibition one of the widest studied methods used to determine the potential activity of natural products to inhibit dietary fat absorption. Decrease of energy intake from dietary fat through inhibition of this enzyme may be an excellent strategy to prevent and treat obesity. The inhibitory activity on pancreatic lipase enzyme of Diospyros kaki fruit and Citrus unshiu peel mixture extract (PCM) was evaluated in vitro and its antiobesity effects were studied based on the serum lipid parameters analysis from high-fat diet- (HFD-) fed mice in vivo. PCM was orally administered at a dose of 50 and 200 mg/kg body weight for 6 weeks. In addition, the activity of pancreatic lipase was assessed using orlistat (positive control). PCM exhibited inhibitory effect on lipase activity with IC50 value of 507.01 μg/mL. Moreover, serum triacylglycerol, total cholesterol levels, and visceral fat weight were significantly reduced compared to HFD control mice in PCM 200 mg/kg-treated mice (p < 0.05). These results suggest that PCM administration may be a novel potential antiobesity agent for reduction of fat absorption via inhibition of pancreatic lipase. PMID:27529064

  7. Study of Antiobesity Effect through Inhibition of Pancreatic Lipase Activity of Diospyros kaki Fruit and Citrus unshiu Peel

    Directory of Open Access Journals (Sweden)

    Gyo-Nam Kim

    2016-01-01

    Full Text Available Pancreatic lipase is the enzyme responsible for digestion and absorption of triglycerides, being its inhibition one of the widest studied methods used to determine the potential activity of natural products to inhibit dietary fat absorption. Decrease of energy intake from dietary fat through inhibition of this enzyme may be an excellent strategy to prevent and treat obesity. The inhibitory activity on pancreatic lipase enzyme of Diospyros kaki fruit and Citrus unshiu peel mixture extract (PCM was evaluated in vitro and its antiobesity effects were studied based on the serum lipid parameters analysis from high-fat diet- (HFD- fed mice in vivo. PCM was orally administered at a dose of 50 and 200 mg/kg body weight for 6 weeks. In addition, the activity of pancreatic lipase was assessed using orlistat (positive control. PCM exhibited inhibitory effect on lipase activity with IC50 value of 507.01 μg/mL. Moreover, serum triacylglycerol, total cholesterol levels, and visceral fat weight were significantly reduced compared to HFD control mice in PCM 200 mg/kg-treated mice (p<0.05. These results suggest that PCM administration may be a novel potential antiobesity agent for reduction of fat absorption via inhibition of pancreatic lipase.

  8. Lipases: particularly effective biocatalysts for cosmetic active ingredients

    Directory of Open Access Journals (Sweden)

    Yvergnaux Florent

    2017-07-01

    Full Text Available Enzymes are the tools of choice in the on-going quest for non-pollutant processes to discover molecules for use in skin products. Amongst these biocatalysts, lipases offer considerable potential in terms of ingredient development and are of interest in skin dermocosmetic formulations possessing sensory or biological activities. Lipases have been studied for around thirty years and, in most cases, these enzymes function under what are deemed to be mild conditions, displaying remarkable efficacy particularly in terms of selectivity. This particularly effective strategy will be illustrated through typical synthesis, demonstrating how ester or amide active ingredients are obtained.

  9. [Structure and Activity of Fungal Lipases in Bile Salt Solutions].

    Science.gov (United States)

    Bogdanova, L R; Bakirova, D R; Valiullina, Yu A; Idiyatullin, B Z; Faizullin, D A; Zueva, O S; Zuev, Yu F

    2016-01-01

    The changes in structure and catalytic properties of fungal lipases (Candida rugosa, Rhizomucor miehei, Mucor javanicus) were investigated in micellar solutions of bile salts that differ in hydrophilic-lypophilic balance and reaction medium properties. The methods of circular dichroism and tryptophan fluorescence were applied to estimate the changes in peptide structure within complexes with bile salt micelles. Bile salts do not exert a significant influence on the structure of the enzymes under study: in Rh. miehei and M. javanicus lipases the alpha helix content slightly decreased, the influence of bile salts on the C. rugosa structure was not revealed. Despite negligible structural modifications in the enzymes, in bile salt solutions a considerable change in their catalytic properties was observed: an abrupt decrease in catalytic effectiveness. Substrate-bile salts micelles complex formation was demonstrated by the NMR self-diffusion method. The model of a regulation of fungal lipase activity was proposed.

  10. Extraction and Characteristics of Anti-obesity Lipase Inhibitor from Phellinus linteus.

    Science.gov (United States)

    Lee, Jong-Kug; Jang, Jeong-Hoon; Lee, Jong-Tae; Lee, Jong-Soo

    2010-03-01

    To develop a potent anti-obesity lipase inhibitor from mushroom, the lipase inhibitory activities of various mushroom extracts were determined. Methanol extracts from Phellinus linteus fruiting body exhibited the highest lipase inhibitory activity (72.8%). The inhibitor was maximally extracted by treatment of a P. linteus fruiting body with 80% methanol at 40℃ for 24 hr. After partial purification by systematic solvent extraction, the inhibitor was stable in the range of 40~80℃ and pH 2.0~9.0. In addition to lipase inhibitory activity, the inhibitor showed 59.4% of superoxide dismutase-like activity and 56.3% of acetylcholinesterase inhibitory activity.

  11. Identification of a novel boronic acid as a potent, selective, and orally active hormone sensitive lipase inhibitor.

    Science.gov (United States)

    Ogiyama, Tomoko; Yamaguchi, Mitsuhiro; Kurikawa, Nobuya; Honzumi, Shoko; Yamamoto, Yuka; Sugiyama, Daisuke; Inoue, Shinichi

    2016-08-15

    Hormone sensitive lipase (HSL) is an attractive therapeutic target of dyslipidemia. We designed and synthesized several compounds as reversible HSL inhibitors with a focus on hydrophobic interactions, which was thought to be effective upon the HSL inhibitory activity. In these efforts, we identified boronated compound 12 showing a potent HSL inhibitory activity with an IC50 value of 7nM and a high selectivity against cholinesterases. Furthermore, compound 12 is the first boron containing HSL inhibitor that has shown an antilipolytic effect in rats after oral administration at 3mg/kg. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Production of a novel cold-active lipase from Pichia lynferdii Y-7723.

    Science.gov (United States)

    Kim, Hak-Ryul; Kim, In-Hwan; Hou, Ching T; Kwon, Kwang-Il; Shin, Beom-Soo

    2010-01-27

    Lipase (triacylglycerol acylhydrolases, E.C. 3.1.1.3) is one of the most important enzymes applied to a broad range of industrial application fields. Especially, lipases with abnormal functionality such as thermostability and alkaline, acidic, and cold activities gain special attention because of their applicability in the restricted reaction conditions. In this study, 16 yeast strains prescreened for lipase induction were investigated for their actual lipase production, and we found a novel cold-active lipase produced from Pichia lynferdii Y-7723. The activity of lipase Y-7723 was retained by 74 and 70% at 20 and 10 degrees C, respectively, as compared to the maximum value at 35 degrees C. On the basis of an optimization study, the optimal lipase productivity was obtained at 96 h of incubation with 3% oil substrate in a medium composed of sucrose as a carbon source at pH 7.0. Among carbon sources tested, sucrose showed almost twice as high of a lipase production (184%) as the control, while the cell growth was similar (105%). Yeast extract and ammonium salts were effective as individual nitrogen sources for lipase production. This study demonstrated that the cold activity of lipase Y-7723 at 10 degrees C was highest among the cold-active lipases reported so far.

  13. Activity and tissue-specific expression of lipases and tumor-necrosis factor alpha in lean and obese cats.

    NARCIS (Netherlands)

    Hoenig, M.; McGoldrick, J.B.; Beer, M. de; Demacker, P.N.M.; Ferguson, D.C.

    2006-01-01

    Post-heparin plasma activity of lipoprotein lipase (LPL) and hepatic lipase (HL), and fat and muscle activity of LPL were measured in neutered lean and obese cats. Lipoprotein lipase, hormone-sensitive lipase (HSL), and tumor necrosis factor a (TNF) mRNA were measured in muscle and fat tissue with r

  14. Activity and tissue-specific expression of lipases and tumor-necrosis factor alpha in lean and obese cats.

    NARCIS (Netherlands)

    Hoenig, M.; McGoldrick, J.B.; Beer, M. de; Demacker, P.N.M.; Ferguson, D.C.

    2006-01-01

    Post-heparin plasma activity of lipoprotein lipase (LPL) and hepatic lipase (HL), and fat and muscle activity of LPL were measured in neutered lean and obese cats. Lipoprotein lipase, hormone-sensitive lipase (HSL), and tumor necrosis factor a (TNF) mRNA were measured in muscle and fat tissue with r

  15. Activity and tissue-specific expression of lipases and tumor-necrosis factor alpha in lean and obese cats.

    NARCIS (Netherlands)

    Hoenig, M.; McGoldrick, J.B.; Beer, M. de; Demacker, P.N.M.; Ferguson, D.C.

    2006-01-01

    Post-heparin plasma activity of lipoprotein lipase (LPL) and hepatic lipase (HL), and fat and muscle activity of LPL were measured in neutered lean and obese cats. Lipoprotein lipase, hormone-sensitive lipase (HSL), and tumor necrosis factor a (TNF) mRNA were measured in muscle and fat tissue with

  16. Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) deficiencies affect expression of lipolytic activities in mouse adipose tissues.

    Science.gov (United States)

    Morak, Maria; Schmidinger, Hannes; Riesenhuber, Gernot; Rechberger, Gerald N; Kollroser, Manfred; Haemmerle, Guenter; Zechner, Rudolf; Kronenberg, Florian; Hermetter, Albin

    2012-12-01

    Adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) are key enzymes involved in intracellular degradation of triacylglycerols. It was the aim of this study to elucidate how the deficiency in one of these proteins affects the residual lipolytic proteome in adipose tissue. For this purpose, we compared the lipase patterns of brown and white adipose tissue from ATGL (-/-) and HSL (-/-) mice using differential activity-based gel electrophoresis. This method is based on activity-recognition probes possessing the same substrate analogous structure but carrying different fluorophores for specific detection of the enzyme patterns of two different tissues in one electrophoresis gel. We found that ATGL-deficiency in brown adipose tissue had a profound effect on the expression levels of other lipolytic and esterolytic enzymes in this tissue, whereas HSL-deficiency hardly showed any effect in brown adipose tissue. Neither ATGL- nor HSL-deficiency greatly influenced the lipase patterns in white adipose tissue. Enzyme activities of mouse tissues on acylglycerol substrates were analyzed as well, showing that ATGL-and HSL-deficiencies can be compensated for at least in part by other enzymes. The proteins that responded to ATGL-deficiency in brown adipose tissue were overexpressed and their activities on acylglycerols were analyzed. Among these enzymes, Es1, Es10, and Es31-like represent lipase candidates as they catalyze the hydrolysis of long-chain acylglycerols.

  17. Structure of product-bound SMG1 lipase: active site gating implications.

    Science.gov (United States)

    Guo, Shaohua; Xu, Jinxin; Pavlidis, Ioannis V; Lan, Dongming; Bornscheuer, Uwe T; Liu, Jinsong; Wang, Yonghua

    2015-12-01

    Monoacylglycerol and diacylglycerol lipases are industrially interesting enzymes, due to the health benefits that arise from the consumption of diglycerides compared to the traditional triglyceride oils. Most lipases possess an α-helix (lid) directly over the catalytic pocket which regulates the activity of the enzyme. Generally, lipases exist in active and inactive conformations, depending on the positioning of this lid subdomain. However, lipase SMG1, a monoacylglycerol and diacylglycerol specific lipase, has an atypical activation mechanism. In the present study we were able to prove by crystallography, in silico analysis and activity tests that only two positions, residues 102 and 278, are responsible for a gating mechanism that regulates the active and inactive states of the lipase, and that no significant structural changes take place during activation except for oxyanion hole formation. The elucidation of the gating effect provided data enabling the rational design of improved lipases with 6-fold increase in the hydrolytic activity toward diacylglycerols, just by providing additional substrate stabilization with a single mutation (F278N or F278T). Due to the conservation of F278 among the monoacylglycerol and diacylglycerol lipases in the Rhizomucor miehei lipase-like family, the gating mechanism described herein might represent a general mechanism applicable to other monoacylglycerol and diacylglycerol lipases as well. Database: Structural data are available in the Protein Data Bank under the accession numbers 4ZRE (F278D mutant) and 4ZRD (F278N mutant).

  18. QSAR study and the hydrolysis activity prediction of three alkaline lipases from different lipase-producing microorganisms.

    Science.gov (United States)

    Wang, Haikuan; Wang, Xiaojie; Li, Xiaolu; Zhang, Yehong; Dai, Yujie; Guo, Changlu; Zheng, Heng

    2012-09-28

    The hydrolysis activities of three alkaline lipases, L-A1, L-A2 and L-A3 secreted by different lipase-producing microorganisms isolated from the Bay of Bohai, P. R. China were characterized with 16 kinds of esters. It was found that all the lipases have the ability to catalyze the hydrolysis of the glycerides, methyl esters, ethyl esters, especially for triglycerides, which shows that they have broad substrate spectra, and this property is very important for them to be used in detergent industry. Three QSAR models were built for L-A1, L-A2 and L-A3 respectively with GFA using Discovery studio 2.1. The models equations 1, 2 and 3 can explain 95.80%, 97.45% and 97.09% of the variances (R(2)(adj)) respectively while they could predict 95.44%, 89.61% and 93.41% of the variances (R(2)(cv)) respectively. With these models the hydrolysis activities of these lipases to mixed esters were predicted and the result showed that the predicted values are in good agreement with the measured values, which indicates that this method can be used as a simple tool to predict the lipase activities for single or mixed esters.

  19. QSAR study and the hydrolysis activity prediction of three alkaline lipases from different lipase-producing microorganisms

    Directory of Open Access Journals (Sweden)

    Wang Haikuan

    2012-09-01

    Full Text Available Abstract The hydrolysis activities of three alkaline lipases, L-A1, L-A2 and L-A3 secreted by different lipase-producing microorganisms isolated from the Bay of Bohai, P. R. China were characterized with 16 kinds of esters. It was found that all the lipases have the ability to catalyze the hydrolysis of the glycerides, methyl esters, ethyl esters, especially for triglycerides, which shows that they have broad substrate spectra, and this property is very important for them to be used in detergent industry. Three QSAR models were built for L-A1, L-A2 and L-A3 respectively with GFA using Discovery studio 2.1. The models equations 1, 2 and 3 can explain 95.80%, 97.45% and 97.09% of the variances (R2adj respectively while they could predict 95.44%, 89.61% and 93.41% of the variances (R2cv respectively. With these models the hydrolysis activities of these lipases to mixed esters were predicted and the result showed that the predicted values are in good agreement with the measured values, which indicates that this method can be used as a simple tool to predict the lipase activities for single or mixed esters.

  20. Pancreas-specific lipase concentrations and amylase and lipase activities in the peritoneal fluid of dogs with suspected pancreatitis.

    Science.gov (United States)

    Chartier, Marie A; Hill, Steve L; Sunico, Sarena; Suchodolski, Jan S; Robertson, Jane E; Steiner, Joerg M

    2014-09-01

    Diagnosing acute pancreatitis in the dog can be challenging. The aim of this study was to determine the concentrations of pancreas-specific lipase immunoreactivity (cPLI), and the activities of amylase and lipase, in the peritoneal fluid from a population of dogs diagnosed with acute pancreatitis based on clinical signs, ultrasonographic findings and serum cPLI concentrations. In a prospective study, cPLI concentrations, and amylase and lipase activities, were measured in the peritoneal fluid of 14 dogs with pancreatitis and 19 dogs with non-pancreatic disease. The sensitivity and specificity of peritoneal fluid cPLI concentration (cut-off value 500 µg/L) were 100.0% (95% confidence interval, CI, 80.7-100.0%) and 94.7% (95% CI 76.7-99.7%), respectively. The sensitivity and specificity of peritoneal fluid amylase (cut-off value 1050 U/L) and lipase activities (cut-off value 500 U/L) were 71.4% (95% CI 44.5-90.2%) and 84.2% (95% CI 62.8-95.8%) for amylase activity, and 92.9% (95% CI 69.5-99.6%) and 94.7% (95% CI 76.7-99.7%) for lipase activity, respectively. In conclusion, peritoneal fluid cPLI concentration was highly sensitive as a complementary diagnostic tool in a group of dogs with suspected acute pancreatitis. Peritoneal fluid lipase activity was not as sensitive as cPLI concentration, but may also support a diagnosis of acute pancreatitis in dogs. Published by Elsevier Ltd.

  1. Glymes as new solvents for lipase activation and biodiesel preparation.

    Science.gov (United States)

    Tang, Shaokun; Jones, Cecil L; Zhao, Hua

    2013-02-01

    Glymes (i.e. glycol diethers) were explored as alternative benign solvents for enzymatic reactions, specifically the lipase-catalyzed transesterification. Long-chain glymes were found highly compatible with immobilized Candida antarctica lipase B (iCALB), leading to higher enzyme activities and stabilities than t-butanol and ionic liquids (e.g. the rate of transesterification in diethylene glycol dibutyl ether (G2-Bu) was 77% higher than that in t-butanol). Furthermore, soybean oil was found fully miscible with glymes, which enabled a homogeneous reaction mixture for the enzymatic preparation of biodiesel. In the presence of glymes, CALB showed a very high tolerance to high methanol concentrations (up to 60-70% v/v), and nearly stoichiometric triglyceride conversions could be obtained under mild reaction conditions. A laboratory scale-up achieved a high conversion of soybean oil (95.5%). This study suggests that glymes can be environmentally friendly and inexpensive solvents for lipase-catalyzed reactions, such as the enzymatic preparation of biodiesel.

  2. PPARγ as a sensor of lipase activity and a target for the lipase inhibitor orlistat.

    Science.gov (United States)

    Martin, Harry; McGhie, Tony K; Bentley-Hewitt, Kerry; Christeller, John

    2013-04-08

    A PPARγ fluorescence polarization (FP) assay was used to measure the release of fatty acid products from triglyceride emulsions during digestion with pancreatic and yeast lipases in a real-time, homogenous assay. Using the same FP assay we show the anti-obesity drug Orlistat is a PPARγ ligand with an IC50 of 2.84 ± 0.16 μM. Analytical Mass Spectrometry confirms that Orlistat does not bind covalently to PPARγ. The PPARγ FP assay is shown to be a simple method for measuring real-time lipase activity using a number of triglyceride substrates including olive oil and grape seed oil emulsions. Incubation of Orlistat with the human intestinal epithelial cell line Caco-2, at concentrations of 1 - 100 μM, leads to induction of genes regulated by PPARγ. At 100 μM Orlistat, transcription of β-defensin 1 (hDB1) & Adipose Differentiation Related Protein (ADRP) increase by up to 2.6 fold and 6.8 fold, respectively. Although at 1 μM and 100 μM Orlistat did not significantly increase defensin protein synthesis, at 10 μM Orlistat induced a 1.5 fold increase in hDB1 protein secretion in the human colonic adenocarcinoma cell line HT-29. Thus Orlistat is similar to the anti-diabetic drug Rosiglitazone in its ability to induce defensin gene expression. The antimicrobial peptide β-defensin 1 protects against pathogenic micro-organisms in the gut and PPARγ suppresses inflammatory gene expression. These may be beneficial side effects of Orlistat consumption on gut epithelial cells.

  3. Factors influencing the activity and thermostability of immobilized porcine pancreatic lipase.

    Science.gov (United States)

    Kéry, V; Haplová, J; Tihlárik, K; Schmidt, S

    1990-01-01

    Lipase from porcine pancreas was immobilized on cellulose beads having various degrees of hydrophobicity, by covalent linking and by hydrophobic adsorption. Lipolytic activity was measured in heterogeneous organic-aqueous systems of various hydrophobicities using olive oil as a substrate. The main factors influencing lipase activity were hydrophobicity of the reaction mixture and of the carrier. Carriers with increased hydrophobicity enhanced lipase activity more than less hydrophobic ones. Lipase immobilized covalently on cellulose beads was less active than that adsorbed onto tritylcellulose but was considerably more thermostable.

  4. Investigation of the Reuse of Immobilized Lipases in Biodiesel Synthesis: Influence of Different Solvents in Lipase Activity.

    Science.gov (United States)

    Aguieiras, Erika C G; Ribeiro, Douglas S; Couteiro, Pedro P; Bastos, Caenam M B; de Queiroz, Danielle S; Parreira, Juliana M; Langone, Marta A P

    2016-06-01

    Biodiesel production catalyzed by immobilized lipases offers the possibility of easy reuse of the catalyst, which is very important to minimize costs and to make this process economically feasible. In this study, the reuse of three commercial immobilized lipases (Novozym 435, Lipozyme RM IM, and Lipozyme TL IM) was investigated in ethanolysis of soybean oil. The effect of the use of solvents (ethanol, butanol, and hexane) to wash the immobilized lipases before the enzyme reuse was evaluated, as well as the lipase reuse without solvent washing. The washing with butanol and ethanol led to the lowest decrease in ester yield after the first batch and allowed the highest glycerol removal (>85 %) from biocatalysts. The biocatalysts were incubated at 50 °C for 2 h in these three solvents. Esterification activities of the enzyme preparations, scanning electron microscopy (SEM) analyses of the beads, and protein content in organic phase were evaluated before and after incubation in the solvent. SEM analysis showed a significant change in beads morphology of Novozym 435 after contact with hexane. For Lipozyme TL IM lipase, this effect was visualized with ethanol.

  5. Collagen-Immobilized Lipases Show Good Activity and Reusability for Butyl Butyrate Synthesis.

    Science.gov (United States)

    Dewei, Song; Min, Chen; Haiming, Cheng

    2016-11-01

    Candida rugosa lipases were immobilized onto collagen fibers through glutaraldehyde cross-linking method. The immobilization process has been optimized. Under the optimal immobilization conditions, the activity of the collagen-immobilized lipase reached 340 U/g. The activity was recovered of 28.3 % by immobilization. The operational stability of the obtained collagen-immobilized lipase for hydrolysis of olive oil emulsion was determined. The collagen-immobilized lipase showed good tolerance to temperature and pH variations in comparison to free lipase. The collagen-immobilized lipase was also applied as biocatalyst for synthesis of butyl butyrate from butyric acid and 1-butanol in n-hexane. The conversion yield was 94 % at the optimal conditions. Of its initial activity, 64 % was retained after 5 cycles for synthesizing butyl butyrate in n-hexane.

  6. Determination of lipase activity in the larval midgut of Bacterocera oleae Gmelin (Diptera: Tephritidae

    Directory of Open Access Journals (Sweden)

    S Delkash-Roudsari

    2014-02-01

    Full Text Available In the current study, digestive lipase activity was determined and characterized in the third larval instars of olive fly, Bactericera oleae as the first time in dipteran order. By using two sample fractions, it was found that the enzyme had higher activity in membrane-bound fraction than that of soluble fraction. Optimal pH of soluble lipase was found to be 4 and 6 but membrane-bound lipase showed pH 4 as optimal value. Optimal temperatures for soluble and membrane-bound lipase were obtained to be 35 and 50 °C, respectively. Activities of digestive soluble and membrane-bound lipases decreased by using various mono- and di-valent ions. Since, fruits of olive are full of various oils, digestive lipases of B. oleae larvae have critical role in their digestion. So, these enzymes might be a good target for developing inhibitors and resistant varieties.

  7. Lipolytic activity of porcine pancreas lipase on fatty acid esters of dialkylglycerols: a structural basis for the design of new substrates for the assay of pancreatic lipases activity.

    Science.gov (United States)

    Ciuffreda, P; Loseto, A; Manzocchi, A; Santaniello, E

    2001-06-01

    For the design of new synthetic substrates for the assay of pancreatic lipases activity, acyl dialkylglycerols of variable chain length were prepared. Titrimetric assay of these substrates showed the highest lipolytic activity of porcine pancreas lipase (pPL) with butanoyl dibutylglycerol. The activity is lower but comparable to that shown by pPL towards the classical substrate tributyrin. The 4-nitrophenylcarbonate of 1,2-di-O-butylglycerol, has been prepared and proposed as synthetic substrate for a new spectrophotometric assay of pancreatic lipases.

  8. The galactolipase activity of Fusarium solani (phospho)lipase.

    Science.gov (United States)

    Jallouli, Raida; Othman, Houcemeddine; Amara, Sawsan; Parsiegla, Goetz; Carriere, Frédéric; Srairi-Abid, Najet; Gargouri, Youssef; Bezzine, Sofiane

    2015-03-01

    The purified (phospho)lipase of Fusarium solani (FSL), was known to be active on both triglycerides and phospholipids. This study aimed at assessing the potential of this enzyme in hydrolyzing galactolipids. FSL was found to hydrolyze at high rates of synthetic medium chains monogalactosyldiacylglycerol (4658±146U/mg on DiC8-MGDG) and digalactosyldiacylglycerol (3785±83U/mg on DiC8-DGDG) and natural long chain monogalactosyldiacylglycerol extracted from leek leaves (991±85U/mg). It is the microbial enzyme with the highest activity on galactolipids identified so far with a level of activity comparable to that of pancreatic lipase-related protein 2. FSL maximum activity on galactolipids was measured at pH8. The analysis of the hydrolysis product of natural MGDG from leek showed that FSL hydrolyzes preferentially the ester bond at the sn-1 position of galactolipids. To investigate the structure-activity relationships of FSL, a 3D model of this enzyme was built. In silico docking of medium chains MGDG and DGDG and phospholipid in the active site of FSL reveals structural solutions which are in concordance with in vitro tests.

  9. Improved activity and thermostability of Bacillus pumilus lipase by directed evolution

    NARCIS (Netherlands)

    Akbulut, Nagihan; Ozturk, Merve Tuzlakoglu; Pijning, Tjaard; Ozturk, Saliha Issever; Gumusel, Fusun

    2013-01-01

    To improve enzymatic activity of Bacillus pumilus lipases, DNA shuffling was applied to two lipase genes from local B. pumilus isolates. Using a high-throughput activity assay, the mutant with highest activity was selected. This chimeric mutant (L3-3), carrying two crossover positions and three poin

  10. Porcine Pancreatic Lipase Related Protein 2 has High Triglyceride Lipase Activity in the Absence of Colipase

    OpenAIRE

    2013-01-01

    Efficient dietary fat digestion is essential for newborns who consume more dietary fat per body weight than at any other time of life. In many mammalian newborns, pancreatic lipase related protein 2 (PLRP2) is the predominant duodenal lipase. Pigs may be an exception since PLRP2 expression has been documented in the intestine but not in the pancreas. Because of the differences in tissue-specific expression, we hypothesized that the kinetic properties of porcine PLRP2 would differ from those o...

  11. Biological activities of a mixture of biosurfactant from Bacillus subtilis and alkaline lipase from Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Cedenir Pereira de Quadros

    2011-03-01

    Full Text Available In this study, we investigate the antimicrobial effects of a mixture of a biosurfactant from Bacillus subtilis and an alkaline lipase from Fusarium oxysporum (AL/BS mix on several types of microorganisms, as well as their abilities to remove Listeria innocua ATCC 33093 biofilm from stainless steel coupons. The AL/BS mix had a surface tension of around 30 mN.m-1, indicating that the presence of alkaline lipase did not interfere in the surface activity properties of the tensoactive component. The antimicrobial activity of the AL/BS mix was determined by minimum inhibitory concentration (MIC micro-assays. Among all the tested organisms, the presence of the mixture only affected the growth of B. subtilis CCT 2576, B. cereus ATCC 10876 and L. innocua. The most sensitive microorganism was B. cereus (MIC 0.013 mg.mL-1. In addition, the effect of the sanitizer against L. innocua attached to stainless steel coupons was determined by plate count after vortexing. The results showed that the presence of the AL/BS mix improved the removal of adhered cells relative to treatment done without the sanitizer, reducing the count of viable cells by 1.72 log CFU.cm-2. However, there was no significant difference between the sanitizers tested and an SDS detergent standard (p<0.05.

  12. Lipase active-site-directed anchoring of organometallics: metallopincer/protein hybrids.

    Science.gov (United States)

    Kruithof, Cornelis A; Casado, Miguel A; Guillena, Gabriela; Egmond, Maarten R; van der Kerk-van Hoof, Anca; Heck, Albert J R; Klein Gebbink, Robertus J M; van Koten, Gerard

    2005-11-18

    The work described herein presents a strategy for the regioselective introduction of organometallic complexes into the active site of the lipase cutinase. Nitrophenol phosphonate esters, well known for their lipase inhibitory activity, are used as anchor functionalities and were found to be ideal tools to develop a single-site-directed immobilization method. A small series of phosphonate esters, covalently attached to ECE "pincer"-type d8-metal complexes through a propyl tether (ECE=[C6H3(CH2E)(2)-2,6]-; E=NR2 or SR), were designed and synthesized. Cutinase was treated with these organometallic phosphonate esters and the new metal-complex/protein hybrids were identified as containing exactly one organometallic unit per protein. The organometallic proteins were purified by membrane dialysis and analyzed by ESI-mass spectrometry. The major advantages of this strategy are: 1) one transition metal can be introduced regioselectively and, hence, the metal environment can potentially be fine-tuned; 2) purification procedures are facile due to the use of pre-synthesized metal complexes; and, most importantly, 3) the covalent attachment of robust organometallic pincer complexes to an enzyme is achieved, which will prevent metal leaching from these hybrids. The approach presented herein can be regarded as a tool in the development of regio- and enantioselective catalyst as well as analytical probes for studying enzyme properties (e.g., structure) and, hence, is a "proof-of-principle design" study in enzyme chemistry.

  13. Activity and Spatial Distribution of Candida antarctica Lipase B Immobilized on Macroporous Organic Polymeric Adsorbents

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Andric, Pavle; Munk Nielsen, Per

    2014-01-01

    A systematic study of the influence of carrier particle size (500 − 850 μ m) and enzyme load (26 200 − 66 100 lipase activity units (LU)/g dry carrier) on the content and activity of Candida antarctica lipase B (CALB) immobilized by adsorption onto macroporous poly(methyl methacrylate) (PMM...

  14. Cloning and expression of gene, and activation of an organic solvent-stable lipase from Pseudomonas aeruginosa LST-03.

    Science.gov (United States)

    Ogino, Hiroyasu; Katou, Yoshikazu; Akagi, Rieko; Mimitsuka, Takashi; Hiroshima, Shinichi; Gemba, Yuichi; Doukyu, Noriyuki; Yasuda, Masahiro; Ishimi, Kosaku; Ishikawa, Haruo

    2007-11-01

    Organic solvent-tolerant Pseudomonas aeruginosa LST-03 secretes an organic solvent-stable lipase, LST-03 lipase. The gene of the LST-03 lipase (Lip9) and the gene of the lipase-specific foldase (Lif9) were cloned and expressed in Escherichia coli. In the cloned 2.6 kbps DNA fragment, two open reading frames, Lip9 consisting of 933 nucleotides which encoded 311 amino acids and Lif9 consisting of 1,020 nucleotides which encoded 340 amino acids, were found. The overexpression of the lipase gene (lip9) was achieved when T7 promoter was used and the signal peptide of the lipase was deleted. The expressed amount of the lipase was greatly increased and overexpressed lipase formed inclusion body in E. coli cell. The collected inclusion body of the lipase from the cell was easily solubilized by urea and activated by using lipase-specific foldase of which 52 or 58 amino acids of N-terminal were deleted. Especially, the N-terminal methionine of the lipase of which the signal peptide was deleted was released in E. coli and the amino acid sequence was in agreement with that of the originally-produced lipase by P. aeruginosa LST-03. Furthermore, the overexpressed and solubilized lipase of which the signal peptide was deleted was more effectively activated by lipase-specific foldase.

  15. Isolation of lipase producing Bacillus sp. from olive mill wastewater and improving its enzyme activity.

    Science.gov (United States)

    Ertuğrul, Sevgi; Dönmez, Gönül; Takaç, Serpil

    2007-11-19

    The bacteria that could grow on media containing olive mill wastewater (OMW) were isolated and their lipase production capacities were investigated. The strain possessing the highest lipase activity among 17 strains grown on tributyrin agar medium was identified as Bacillus sp. The effect of initial pH on the lipase activity was investigated in tributyrin medium and pH 6 was found to be the optimal. The liquid medium composition was improved by replacing tributyrin with various carbon sources. Among the media containing different compositions of triolein, trimyristin, trilaurin, tricaprin, tricaprylin, tributyrin, triacetin, Tween 80, OMW, glucose, and whey; the medium contained 20% whey +1% triolein was found to give the highest lipase activity. Cultivation of Bacillus sp. in the optimal medium at pH 6 and 30 degrees C for 64h resulted in the extracellular and intracellular lipase activities of 15 and 168U/ml, respectively.

  16. Effect of membranes with various hydrophobic/hydrophilic properties on lipase immobilized activity and stability.

    Science.gov (United States)

    Chen, Guan-Jie; Kuo, Chia-Hung; Chen, Chih-I; Yu, Chung-Cheng; Shieh, Chwen-Jen; Liu, Yung-Chuan

    2012-02-01

    In this study, three membranes: regenerated cellulose (RC), glass fiber (GF) and polyvinylidene fluoride (PVDF), were grafted with 1,4-diaminobutane (DA) and activated with glutaraldehyde (GA) for lipase covalent immobilization. The efficiencies of lipases immobilized on these membranes with different hydrophobic/hydrophilic properties were compared. The lipase immobilized on hydrophobic PVDF-DA-GA membrane exhibited more than an 11-fold increase in activity compared to its immobilization on a hydrophilic RC-DA-GA membrane. The relationship between surface hydrophobicity and immobilized efficiencies was investigated using hydrophobic/hydrophilic GF membranes which were prepared by grafting a different ratio of n-butylamine/1,4-diaminobutane (BA/DA). The immobilized lipase activity on the GF membrane increased with the increased BA/DA ratio. This means that lipase activity was exhibited more on the hydrophobic surface. Moreover, the modified PVDF-DA membrane was grafted with GA, epichlorohydrin (EPI) and cyanuric chloride (CC), respectively. The lipase immobilized on the PVDF-DA-EPI membrane displayed the highest specific activity compared to other membranes. This immobilized lipase exhibited more significant stability on pH, thermal, reuse, and storage than did the free enzyme. The results exhibited that the EPI modified PVDF is a promising support for lipase immobilization.

  17. Improved acylation of phytosterols catalyzed by Candida antarctica lipase A with superior catalytic activity

    DEFF Research Database (Denmark)

    Panpipat, Worawan; Xu, Xuebing; Guo, Zheng

    2013-01-01

    This work reported a novel approach to synthesize phytosterol (ˇ-sitosterol as a model) fatty acid esters by employing Candida antarctica lipase A (CAL A) which shows a superior catalytic activity to other lipases. A series of ˇ-sitosteryl fatty acid esters (C2–C18) have been successfully prepared...

  18. Post-heparin plasma lipoprotein lipase, but not hepatic lipase activity, is related to plasma adiponectin in type 2 diabetic patients and healthy subjects

    NARCIS (Netherlands)

    De Vries, R; Wolffenbuttel, BHR; Sluiter, WJ; Van Tol, A; Dullaart, RPF

    2005-01-01

    The aim of this study was to determine the relationships of plasma adiponectin with post-heparin plasma lipoprotein lipase (LPL) and hepatic lipase (HL) activities, and to evaluate whether plasma adiponectin contributes to diabetes-associated dyslipidaemia. Plasma adiponectin, post-heparin plasma

  19. Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

    Directory of Open Access Journals (Sweden)

    Soumanou Mohamed M.

    2004-11-01

    Full Text Available Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL and Candida rugosa (CRL was performed. The best substrate molar ratio of tricaprylin to peanut oil found was in the range 0.7 to 0.8. Using substrate molar ratio 0.7, high amount of structured triglyceride ST (about 35% MLM, 44% LML triglyceride fractions was obtained with lipase from RML in n-hexane. The results found in solvent free system were in some cases quite similar to that obtained in organic solvent. In nine successive batch interesterification in solvent free medium using immobilized RML and CRL, no significant loss of amount of both produced triacylglycerol fractions until batch 7 was observed with RML.

  20. Role of active site rigidity in activity: MD simulation and fluorescence study on a lipase mutant.

    Directory of Open Access Journals (Sweden)

    Md Zahid Kamal

    Full Text Available Relationship between stability and activity of enzymes is maintained by underlying conformational flexibility. In thermophilic enzymes, a decrease in flexibility causes low enzyme activity while in less stable proteins such as mesophiles and psychrophiles, an increase in flexibility is associated with enhanced enzyme activity. Recently, we identified a mutant of a lipase whose stability and activity were enhanced simultaneously. In this work, we probed the conformational dynamics of the mutant and the wild type lipase, particularly flexibility of their active site using molecular dynamic simulations and time-resolved fluorescence techniques. In contrast to the earlier observations, our data show that active site of the mutant is more rigid than wild type enzyme. Further investigation suggests that this lipase needs minimal reorganization/flexibility of active site residues during its catalytic cycle. Molecular dynamic simulations suggest that catalytically competent active site geometry of the mutant is relatively more preserved than wild type lipase, which might have led to its higher enzyme activity. Our study implies that widely accepted positive correlation between conformation flexibility and enzyme activity need not be stringent and draws attention to the possibility that high enzyme activity can still be accomplished in a rigid active site and stable protein structures. This finding has a significant implication towards better understanding of involvement of dynamic motions in enzyme catalysis and enzyme engineering through mutations in active site.

  1. Purification and Characterization of a Novel Cold-Active Lipase from the Yeast Candida zeylanoides.

    Science.gov (United States)

    Čanak, Iva; Berkics, Adrienn; Bajcsi, Nikolett; Kovacs, Monika; Belak, Agnes; Teparić, Renata; Maraz, Anna; Mrša, Vladimir

    2015-01-01

    Cold-active lipases have attracted attention in recent years due to their potential applications in reactions requiring lower temperatures. Both bacterial and fungal lipases have been investigated, each having distinct advantages for particular applications. Among yeasts, cold-active lipases from the genera Candida, Yarrowia, Rhodotorula, and Pichia have been reported. In this paper, biosynthesis and properties of a novel cold-active lipase from Candida zeylanoides isolated from refrigerated poultry meat are described. Heat-sterilized olive oil was found to be the best lipase biosynthesis inducer, while nonionic detergents were not effective. The enzyme was purified to homogeneity using hydrophobic chromatography and its enzymatic properties were tested. Pure enzyme activity at 7 °C was about 60% of the maximal activity at 27 °C. The enzyme had rather good activity at higher temperatures, as well. Optimal pH of pure lipase was between 7.3 and 8.2, while the enzyme from the crude extract had an optimum pH of about 9.0. The enzyme was sensitive to high ionic strength and lost most of its activity at high salt concentrations. Due to the described properties, cold-active C. zeylanoides lipase has comparative advantages to most similar enzymes with technological applications and may have potential to become an industrially important enzyme.

  2. Bacterial lipases

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    1994-01-01

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation, mea

  3. Synthetic activity enhancement of membrane-bound lipase from Rhizopus chinensis by pretreatment with isooctane.

    Science.gov (United States)

    Wang, Dong; Xu, Yan; Teng, Yun

    2007-05-01

    The cell-bound lipase from Rhizopus chinensis CCTCC M201021 with high catalysis ability for ester synthesis was located as a membrane-bound lipase by the treatments of Yatalase firstly. In order to improve its synthetic activity in non-aqueous phase, the pretreatments of this enzyme with various organic solvents were investigated. The pretreatment with isooctane improved evidently the lipase synthetic activity, resulting in about 139% in relative synthetic activity and 115% in activity recovery. The morphological changes of mycelia caused by organic solvent pretreatments could influence the exposure of the membrane-bound enzyme from mycelia and the exhibition of the lipase activity. The pretreatment conditions with isooctane and acetone were further investigated, and the optimum effect was obtained by the isooctane pretreatment at 4 degrees C for 1 h, resulting in 156% in relative synthetic activity and 126% in activity recovery. When the pretreated lipases were employed as catalysts for the esterification production of ethyl hexanoate in heptane, higher initial reaction rate and higher final molar conversion were obtained using the lipase pretreated with isooctane, compared with the untreated lyophilized one. This result suggested that the pretreatment of the membrane-bound lipase with isooctane could be an effective method to substitute the lyophilization for preparing biocatalysts used in non-aqueous phase reactions.

  4. Optimization of culture conditions for production of a novel cold-active lipase from Pichia lynferdii NRRL Y-7723.

    Science.gov (United States)

    Park, Sun-Young; Kim, Ji-Yeon; Bae, Jae-Han; Hou, Ching T; Kim, Hak-Ryul

    2013-01-30

    Lipases with abnormal properties such as thermostability, alkalinity, acidity, and cold activity receive industrial attention because of their usability under restricted reaction conditions. Most microbial cold-active lipases originate from psychrotrophic and psychrophilic microorganisms found in Antarctic regions, which has led to difficulties in the practical production of cold-active lipase. Recently, a mesophilic yeast, Pichia lynferdii NRRL Y-7723, was reported to produce a novel cold-active lipase. This study focused on optimization of environmental factors, while giving particular attention to the relationships between given factors and incubation time, to maximize the production of a novel cold-active lipase from P. lynferdii NRRL Y-7723. Maximum lipase production was highly dependent on the incubation time at a given environmental factor. Lipase production varied with incubation time at a given temperature, and 20 °C was selected as the optimum temperature for lipase production. Fructose was selected as the best carbon source, and maximum lipase production was obtained when it was present at 0.7% (w/v). Yeast extract was an efficient organic nitrogen source, with maximum lipase production occurring at 0.9% (w/v). Specifically, at the optimum yeast extract level the lipase production was >10 times higher than the productivity under standard conditions. All natural oils tested showed lipase production, but their maximum productivities varied according to incubation time and oil species.

  5. New Atglistatin closely related analogues: Synthesis and structure-activity relationship towards adipose triglyceride lipase inhibition.

    Science.gov (United States)

    Roy, Pierre-Philippe; D'Souza, Kenneth; Cuperlovic-Culf, Miroslava; Kienesberger, Petra C; Touaibia, Mohamed

    2016-08-01

    Adipose Triglyceride Lipase (ATGL) performs the first and rate-limiting step in lipolysis by hydrolyzing triacylglycerols stored in lipid droplets to diacylglycerols. By mediating lipolysis in adipose and non-adipose tissues, ATGL is a major regulator of overall energy metabolism and plasma lipid levels. Since chronically high levels of plasma lipids are linked to metabolic disorders including insulin resistance and type 2 diabetes, ATGL is an interesting therapeutic target. In the present study, fourteen closely related analogues of Atglistatin (1), a newly discovered ATGL inhibitor, were synthesized, and their ATGL inhibitory activity was evaluated. The effect of these analogues on lipolysis in 3T3-L1 adipocytes clearly shows that inhibition of the enzyme by Atglistatin (1) is due to the presence of the carbamate and N,N-dimethyl moieties on the biaryl central core at meta and para position, respectively. Mono carbamate-substituted analogue C2, in which the carbamate group was in the meta position as in Atglistatin (1), showed slight inhibition. Low dipole moment of Atglistatin (1) compared to the synthesized analogues possibly explains the lower inhibitory activities.

  6. Study on immunocapture-chemiluminescence assay of lipase activity in a biological sample.

    Science.gov (United States)

    Ichibangase, Tomoko; Hamabe, Chie; Ohba, Yoshihito; Kishikawa, Naoya; Nakashima, Kenichiro; Kayamori, Yuzo; Kang, Dongchon; Hamasaki, Naotaka; Kuroda, Naotaka

    2006-01-01

    A new approach for the determination of lipase (triacylglycerol lipase, EC.3.1.1.3) activity in a biological sample was investigated by combining an immunocapture technique with a chemiluminescence (CL) assay method in order to eliminate interference with CL detection. The proposed method consists of an immunocapture step to trap lipase and a subsequent step for CL detection of the activity of the captured lipase. The CL detection is based on the luminol-hydrogen peroxide (H(2)O(2))-horseradish peroxidase (HRP) reaction and utilizes a proenhancer substrate [a lauric acid ester of 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (HDI)] which liberates an active enhancer, HDI, by enzymatic hydrolysis. A polyclonal antibody prepared with porcine pancreas lipase was used for the immunocapture. The proposed immunocapture-CL method effectively eliminated the interference with the CL reaction from biological components and enabled the determination of spiked porcine pancreas lipase activity in serum samples in the range 0.41-1.1 U(HDI) (1 U(HDI) corresponds to the amount which liberates 1 pmol HDI/min at 37 degrees C from the substrate). The method was further applied to the assay of the activity for human pancreas lipase in serum and the results showed good correlation (r = 0.871) with those by the conventional colorimetric method.

  7. A grey mullet enzyme displaying both lipase and phospholipase activities: purification and characterization.

    Science.gov (United States)

    Smichi, Nabil; Gargouri, Youssef; Miled, Nabil; Fendri, Ahmed

    2013-07-01

    A lipase from the golden grey mullet viscera was purified to homogeneity by ammonium sulphate precipitation, gel filtration, anionic and cation exchange chromatographies. The pure enzyme tentatively named grey mullet digestive lipase (GmDL) is a monomer having a molecular mass of about 35 kDa, as determined by SDS-PAGE analysis. No similarity was found between the NH2-terminal amino acid residues of GmDL and those of other known digestive lipases. GmDL is a serine enzyme, like all known lipases from different origins. Interestingly, GmDL has not only lipase activity but also a phospholipase activity which requires the presence of Ca(2+) and bile salts. Specific activities of 64 U/mg, 55 U/mg and 63 U/mg were measured using tributyrin, olive oil emulsion or phosphatidylcholine as substrate, respectively at pH 8 and at 50°C. GmDL is therefore a thermo-active enzyme as compared to other fish lipases studied so far. It is worth to notice that grey mullet lipase was active in the presence of salt concentrations as high as 0.8M.

  8. Effect of temperature on Candida antartica lipase B activity in the kinetic resolution of acebutolol

    Science.gov (United States)

    Rajin, Mariani; Kamaruddin, A. H.

    2016-06-01

    Thermodynamic studies of free Candida antartica lipase B in kinetic resolution of acebutolol have been carried out to characterize the temperature effects towards enzyme stability and activity. A decreased in reaction rate was observed in temperature above 40oC. Thermodynamic studies on lipase deactivation exhibited a first-order kinetic pattern. The activation and deactivation energies were 39.63 kJ/mol and 54.90 kJ/mol, respectively. The enthalpy and entropy of the lipase deactivation were found to be 52.12 kJ/mol and -0.18 kJ/mol, respectively.

  9. Biochemical Properties of a New Cold-Active Mono- and Diacylglycerol Lipase from Marine Member Janibacter sp. Strain HTCC2649

    Directory of Open Access Journals (Sweden)

    Dongjuan Yuan

    2014-06-01

    Full Text Available Mono- and di-acylglycerol lipase has been applied to industrial usage in oil modification for its special substrate selectivity. Until now, the reported mono- and di-acylglycerol lipases from microorganism are limited, and there is no report on the mono- and di-acylglycerol lipase from bacteria. A predicted lipase (named MAJ1 from marine Janibacter sp. strain HTCC2649 was purified and biochemical characterized. MAJ1 was clustered in the family I.7 of esterase/lipase. The optimum activity of the purified MAJ1 occurred at pH 7.0 and 30 °C. The enzyme retained 50% of the optimum activity at 5 °C, indicating that MAJ1 is a cold-active lipase. The enzyme activity was stable in the presence of various metal ions, and inhibited in EDTA. MAJ1 was resistant to detergents. MAJ1 preferentially hydrolyzed mono- and di-acylglycerols, but did not show activity to triacylglycerols of camellia oil substrates. Further, MAJ1 is low homologous to that of the reported fungal diacylglycerol lipases, including Malassezia globosa lipase 1 (SMG1, Penicillium camembertii lipase U-150 (PCL, and Aspergillus oryzae lipase (AOL. Thus, we identified a novel cold-active bacterial lipase with a sn-1/3 preference towards mono- and di-acylglycerides for the first time. Moreover, it has the potential, in oil modification, for special substrate selectivity.

  10. Biochemical properties of a new cold-active mono- and diacylglycerol lipase from marine member Janibacter sp. strain HTCC2649.

    Science.gov (United States)

    Yuan, Dongjuan; Lan, Dongming; Xin, Ruipu; Yang, Bo; Wang, Yonghua

    2014-06-12

    Mono- and di-acylglycerol lipase has been applied to industrial usage in oil modification for its special substrate selectivity. Until now, the reported mono- and di-acylglycerol lipases from microorganism are limited, and there is no report on the mono- and di-acylglycerol lipase from bacteria. A predicted lipase (named MAJ1) from marine Janibacter sp. strain HTCC2649 was purified and biochemical characterized. MAJ1 was clustered in the family I.7 of esterase/lipase. The optimum activity of the purified MAJ1 occurred at pH 7.0 and 30 °C. The enzyme retained 50% of the optimum activity at 5 °C, indicating that MAJ1 is a cold-active lipase. The enzyme activity was stable in the presence of various metal ions, and inhibited in EDTA. MAJ1 was resistant to detergents. MAJ1 preferentially hydrolyzed mono- and di-acylglycerols, but did not show activity to triacylglycerols of camellia oil substrates. Further, MAJ1 is low homologous to that of the reported fungal diacylglycerol lipases, including Malassezia globosa lipase 1 (SMG1), Penicillium camembertii lipase U-150 (PCL), and Aspergillus oryzae lipase (AOL). Thus, we identified a novel cold-active bacterial lipase with a sn-1/3 preference towards mono- and di-acylglycerides for the first time. Moreover, it has the potential, in oil modification, for special substrate selectivity.

  11. Regulation of hepatic lipase activity by sphingomyelin in plasma lipoproteins

    Science.gov (United States)

    Yang, Peng; Subbaiah, Papasani V.

    2015-01-01

    Hepatic lipase (HL) is an important enzyme in the clearance of triacylglycerol (TAG) from the circulation, and has been proposed to have pro-atherogenic as well as anti-atherogenic properties. It hydrolyzes both phospholipids and TAG of lipoproteins, and its activity is negatively correlated with HDL levels. Although it is known that HL acts preferentially on HDL lipids, the basis for this specificity is not known, since it does not require any specific apoprotein for activity. In this study, we tested the hypothesis that sphingomyelin (SM), whose concentration is much higher in VLDL and LDL compared to HDL, is an inhibitor of HL, and that this could explain the lipoprotein specificity of the enzyme. The results presented show that the depletion of SM from normal lipoproteins activated the HL roughly in proportion to their SM content. SM depletion stimulated the hydrolysis of both phosphatidylcholine (PC) and TAG, although the PC hydrolysis was stimulated more. In the native lipoproteins, HL showed specificity for PC species containing polyunsaturated fatty acids at sn-2 position, and produced more unsaturated lyso PC species. The enzyme also showed preferential hydrolysis of certain TAG species over others. SM depletion affected the specificity of the enzyme towards PC and TAG species modestly. These results show that SM is a physiological inhibitor of HL activity in lipoproteins and that the specificity of the enzyme towards HDL is at least partly due to its low SM content. PMID:26193433

  12. Triacylglycerol kinetics in endotoxic rats with suppressed lipoprotein lipase activity

    Energy Technology Data Exchange (ETDEWEB)

    Bagby, G.J.; Corll, C.B.; Martinez, R.R.

    1987-07-01

    Hypertriglyceridemia observed in animals after bacterial endotoxin administration and some forms of sepsis can result from increased hepatic triacylglycerol (TG) output or decreased TG clearance by extrahepatic tissues. To differentiate between these two possibilities, TG and free fatty acid (FFA) kinetics were determined in control and endotoxin-injected rats 18 h after treatment. Plasma TG and FFA kinetics were assessed by a constant intravenous infusion with (9,10-/sup 3/H)palmitate-labeled very low-density lipoprotein and (1-/sup 14/C)palmitate bound to albumin, respectively. In addition, lipoprotein lipase (LPL) activity was determined in heart, skeletal muscle, and adipose tissue as well as in postheparin plasma of functionally hepatectomized, adrenalectomized, and gonadectomized rats. Plasma FFA acid concentrations were slightly increased in endotoxin-treated rats but their turnover did not differ from control. Endotoxin-treated rats had a threefold increase in plasma TG concentrations and decreased heart, skeletal muscle, and post-heparin plasma LPL activity. Plasma TG turnover was decreased, indicating that hypertriglyceridemia was not due to an increased TG output by the liver. Instead, the endotoxin-induced increase in plasma TG concentration was consequence of the 80% reduction in TG metabolic clearance rate. Thus, suppression of LPL activity in endotoxic animals impairs TG clearance resulting in hypertriglyceridemia. Furthermore, endotoxin administration reduced the delivery of TG-FFA to extrahepatic tissues because hepatic synthesis and secretion of TG from plasma FFA was decreased and LPL activity was suppressed.

  13. Gold nanorod in reverse micelles: a fitting fusion to catapult lipase activity.

    Science.gov (United States)

    Maiti, Subhabrata; Ghosh, Moumita; Das, Prasanta Kumar

    2011-09-21

    Lipase solubilized within gold nanorod doped CTAB reverse micelles exhibited remarkable improvement in its activity mainly due to the enhanced interfacial domain of newly developed self-assembled nanocomposites.

  14. [Lipase activity in the calf serum under different types of feeding].

    Science.gov (United States)

    Surynek, J

    1975-05-01

    The development of lipase activity in serum (S-lipase activity) was studied in two groups of the calves of the Bohemian Red-Pied breed in the post-natal period up to the age of nine weeks from birth. From the eighth day of age, the two groups differed from each other in their lactic nutrition. Group A calves were given whole milk (obtained at primary production) and group B calves were fed the Laktosan mixture instead of milk. The different type of nutrition did not influence the character of the development of S-lipase activity with increasing age. A difference was found between the two groups as to the level of the activity of the enzyme under study. In the whole-milk group the average S-lipase activity values were higher than in the group fed Laktosan in a larger part of the test period. Some differences were statistically significant. It is assumed that lipase activity in blood is a reflection of the external secretion of pancreas changing according to the structure of food taken in. The activity of S-lipase was determined by the method according to Cherry and Crandall (Seligson, 1964); the average minimum value was 0.025 +/- 0.0017 u. in group A and 0.017 +/- 0.0081 u. in group B, and the average maximum value was 0.370 +/- 0.100 u. and 0.286 +/- 0.0766 u., respectively.

  15. A novel fluorogenic substrate for the measurement of endothelial lipase activity.

    Science.gov (United States)

    Darrow, Andrew L; Olson, Matthew W; Xin, Hong; Burke, Sharon L; Smith, Charles; Schalk-Hihi, Celine; Williams, Robyn; Bayoumy, Shariff S; Deckman, Ingrid C; Todd, Matthew J; Damiano, Bruce P; Connelly, Margery A

    2011-02-01

    Endothelial lipase (EL) is a phospholipase A1 (PLA1) enzyme that hydrolyzes phospholipids at the sn-1 position to produce lysophospholipids and free fatty acids. Measurement of the PLA1 activity of EL is usually accomplished by the use of substrates that are also hydrolyzed by lipases in other subfamilies such as PLA2 enzymes. In order to distinguish PLA1 activity of EL from PLA2 enzymatic activity in cell-based assays, cell supernatants, and other nonhomogeneous systems, a novel fluorogenic substrate with selectivity toward PLA1 hydrolysis was conceived and characterized. This substrate was preferred by PLA1 enzymes, such as EL and hepatic lipase, and was cleaved with much lower efficiency by lipases that exhibit primarily triglyceride lipase activity, such as LPL or a lipase with PLA2 activity. The phospholipase activity detected by the PLA1 substrate could be inhibited with the small molecule esterase inhibitor ebelactone B. Furthermore, the PLA1 substrate was able to detect EL activity in human umbilical vein endothelial cells in a cell-based assay. This substrate is a useful reagent for identifying modulators of PLA1 enzymes, such as EL, and aiding in characterizing their mechanisms of action.

  16. A plasmonic nanosensor for lipase activity based on enzyme-controlled gold nanoparticles growth in situ

    Science.gov (United States)

    Tang, Yan; Zhang, Wei; Liu, Jia; Zhang, Lei; Huang, Wei; Huo, Fengwei; Tian, Danbi

    2015-03-01

    A plasmonic nanosensor for lipase activity was developed based on one-pot nanoparticle growth. Tween 80 was selected not only as the substrate for lipase recognition but also as the reducing and stabilizing agent for the sensor fabrication. The different molecular groups in Tween 80 could have different roles in the fabrication procedure; the H2O2 produced by the autoxidation of the ethylene oxide subunits in Tween 80 could reduce the AuCl4- ions to Au atoms, meanwhile, the lipase could hydrolyze its carboxyl ester bond, which could, in turn, control the rate of nucleation of the gold nanoparticles (AuNPs) and tailor the localized surface plasmon resonance (LSPR) of the AuNP transducers. The color changes, which depend on the absence or presence of the lipase, could be used to sense the lipase activity. A linear response ranging from 0.025 to 4 mg mL-1 and a detection limit of the lipase as low as 3.47 μg mL-1 were achieved. This strategy circumvents the problems encountered by general enzyme assays that require sophisticated instruments and complicated assembling steps. The methodology can benefit the assays of heterogeneous-catalyzed enzymes.A plasmonic nanosensor for lipase activity was developed based on one-pot nanoparticle growth. Tween 80 was selected not only as the substrate for lipase recognition but also as the reducing and stabilizing agent for the sensor fabrication. The different molecular groups in Tween 80 could have different roles in the fabrication procedure; the H2O2 produced by the autoxidation of the ethylene oxide subunits in Tween 80 could reduce the AuCl4- ions to Au atoms, meanwhile, the lipase could hydrolyze its carboxyl ester bond, which could, in turn, control the rate of nucleation of the gold nanoparticles (AuNPs) and tailor the localized surface plasmon resonance (LSPR) of the AuNP transducers. The color changes, which depend on the absence or presence of the lipase, could be used to sense the lipase activity. A linear response

  17. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle.

    Science.gov (United States)

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel; Brzezinska, Zofia; Klapcinska, Barbara; Galbo, Henrik; Gorski, Jan

    2010-09-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose tissue suggests that testosterone regulates HSL activity. To test whether this is also true in the heart, we measured HSL activity in the left ventricle of sedentary male rats that had been treated with testosterone supplementation or orchidectomy with or without testosterone substitution. Left ventricle HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid levels, caused an inhibitory effect on carbohydrate metabolism in the heart, and elevated left ventricular phosphocreatine and ATP levels as compared to control rats. These data indicate that testosterone is involved in cardiac HSL activity regulation which, in turn, may affect cardiac lipid and carbohydrate metabolism.

  18. Adipose triglyceride lipase regulates eicosanoid production in activated human mast cells.

    Science.gov (United States)

    Dichlberger, Andrea; Schlager, Stefanie; Maaninka, Katariina; Schneider, Wolfgang J; Kovanen, Petri T

    2014-12-01

    Human mast cells (MCs) contain TG-rich cytoplasmic lipid droplets (LDs) with high arachidonic acid (AA) content. Here, we investigated the functional role of adipose TG lipase (ATGL) in TG hydrolysis and the ensuing release of AA as substrate for eicosanoid generation by activated human primary MCs in culture. Silencing of ATGL in MCs by siRNAs induced the accumulation of neutral lipids in LDs. IgE-dependent activation of MCs triggered the secretion of the two major eicosanoids, prostaglandin D2 (PGD2) and leukotriene C4 (LTC4). The immediate release of PGD2 from the activated MCs was solely dependent on cyclooxygenase (COX) 1, while during the delayed phase of lipid mediator production, the inducible COX-2 also contributed to its release. Importantly, when ATGL-silenced MCs were activated, the secretion of both PGD2 and LTC4 was significantly reduced. Interestingly, the inhibitory effect on the release of LTC4 was even more pronounced in ATGL-silenced MCs than in cytosolic phospholipase A2-silenced MCs. These data show that ATGL hydrolyzes AA-containing TGs present in human MC LDs and define ATGL as a novel regulator of the substrate availability of AA for eicosanoid generation upon MC activation.

  19. The surfactant-induced conformational and activity alterations in Rhizopus niveus lipase.

    Science.gov (United States)

    Alam, Parvez; Rabbani, Gulam; Badr, Gamal; Badr, Badr Mohamed; Khan, Rizwan Hasan

    2015-03-01

    In this study, we have reported the effect of nonionic, anionic, cationic, and zwitterionic detergents on the enzymatic activity and structural stability of Rhizopus niveus lipase. Secondary structural changes were monitored by Far-UV CD which shows that surfactant induces helicity in the Rhizopus niveus lipase protein which was maximum in case of CTAB followed by SDS, CHAPS, and Brij-35. Similarly, tertiary structural changes were monitored by tryptophan fluorescence. We also carried out enzyme kinetics assays which showed that activity was enhanced by 1.5- and 1.1-fold in the presence of CHAPS and Brij-35, respectively. Furthermore, there was a decline in activity by 20 and 30 % in case of SDS and CTAB, respectively. These studies may be helpful in understanding detergent-lipase interaction in greater detail as lipases are used in many industrial processes.

  20. Enzymatic activity of a novel halotolerant lipase from Haloarcula hispanica 2TK2

    Directory of Open Access Journals (Sweden)

    Ozgen Melis

    2016-06-01

    Full Text Available A strain of Haloarcula hispanica isolated from Tuzkoy salt mine, Turkey exhibited extracellular lipolytic activity. Important parameters such as carbon sources and salt concentration for lipase production were investigated. Optimal conditions for the enzyme production from Haloarcula hispanica 2TK2 were determined. It was observed that the lipolytic activity of Haloarcula hispanica was stimulated by some of the carbon sources. The high lipase acitivity values were obtained in the presence of 2% (v/v walnut oil (6.16 U/ml, 1% (v/v fish oil (5.07 U/ml, 1% (v/v olive oil (4.52 U/ml and 1% (w/v stearic acid (4.88 U/ml at 4M NaCl concentration. Lipase was partially purified by ammonium sulfate precipitation and ultrafiltration. Optimal temperature and pH values were determined as 45°C and 8.0, respectively. Lipase activity decreased with the increasing salt concentration, but 85% activity of the enzyme was maintained at 5M NaCl concentration. The enzyme preserved 41% of its relative activity at 90°C. The partially purified lipase maintained its activity in the presence of surfactants such as Triton X-100 and SDS. Therefore, the lipase which is an extremozyme may have potential applications especially in detergent industry.

  1. Effects of acute hypoxia on human adipose tissue lipoprotein lipase activity and lipolysis

    OpenAIRE

    Mahat, Bimit; Chassé, Étienne; Mauger, Jean-François; Imbeault, Pascal

    2016-01-01

    Background Adipose tissue regulates postprandial lipid metabolism by storing dietary fat through lipoprotein lipase-mediated hydrolysis of exogenous triglycerides, and by inhibiting delivery of endogenous non-esterified fatty acid to nonadipose tissues. Animal studies show that acute hypoxia, a model of obstructive sleep apnea, reduces adipose tissue lipoprotein lipase activity and increases non-esterified fatty acid release, adversely affecting postprandial lipemia. These observations remain...

  2. Active serine involved in the stabilization of the active site loop in the Humicola lanuginosa lipase

    DEFF Research Database (Denmark)

    Peters, Günther H.j.; Svendsen, A.; Langberg, H.;

    1998-01-01

    reveal that the hinges of the active site lid are more flexible in the wild-type Hll than in S146A. In contrast, larger fluctuations are observed in the middle region of the active site loop in S 146A than in Hll. These findings reveal that the single mutation (S146A) of the active site serine leads......We have investigated the binding properties of and dynamics in Humicola lanuginosa lipase (HII) and the inactive mutant S146A (active Ser146 substituted with Ala) using fluorescence spectroscopy and molecular dynamics simulations, respectively. Hll and S146A show significantly different binding......, whereas only small changes are observed for I-Ill suggesting that the active site Lid in the latter opens more easily and hence more lipase molecules are bound to the liposomes. These observations are in agreement with molecular dynamics simulations and subsequent essential dynamics analyses. The results...

  3. Inhibition of pancreatic lipase and amylase by extracts of different spices and plants.

    Science.gov (United States)

    Sellami, Mohamed; Louati, Hanen; Kamoun, Jannet; Kchaou, Ali; Damak, Mohamed; Gargouri, Youssef

    2017-05-01

    The aim of this study is to search new anti-obesity and anti-diabetic agents from plant and spices crude extracts as alternative to synthetic drugs. The inhibitory effect of 72 extracts was evaluated, in vitro, on lipase and amylase activities. Aqueous extracts of cinnamon and black tea exhibited an appreciable inhibitory effect on pancreatic amylase with IC50 values of 18 and 87 μg, respectively. Aqueous extracts of cinnamon and mint showed strong inhibitory effects against pancreatic lipase with IC50 of 45 and 62 μg, respectively. The presence of bile salts and colipase or an excess of interface failed to restore the lipase activity. Therefore, the inhibition of pancreatic lipase, by extracts of spices and plants, belongs to an irreversible inhibition. Crude extract of cinnamon showed the strongest anti-lipase and anti-amylase activities which offer a prospective therapeutic approach for the management of diabetes and obesity.

  4. Activity and stability of a Rhizomucor miehei lipase in hydrophobic media.

    Science.gov (United States)

    Dellamora-Ortiz, G M; Martins, R C; Rocha, W L; Dias, A P

    1997-08-01

    The effects of detergents and organic solvents on a commercial lipase (Lipozyme) from Rhizomucor miehei were investigated. It was shown that the detergent sodium cholate is possibly an activator of the enzyme, increasing lipase activity 2.5 times (250% of the control) when the enzyme was preincubated with 7 mM cholate. Lipozyme activity was over twice as high (230% of the control) in the presence of 80 mM Tween 80 or 90 mM Tween 20 (polyoxyethylenesorbitan monolaurate), apparently through an additional emulsifying action on the substrate. Preincubation with Tween 80 (polyoxyethylenesorbitan mono-oleate) did not affect enzyme activity. In contrast, lipase activity was completely inhibited in the presence of an 8.9 mM concentration of another non-ionic detergent, Brij 58, whereas with a 16.4 mM concentration of the cationic detergent cetyltrimethylammonium bromide (CTAB), enzyme activity was reduced by 80%. Preincubation of Lipozyme with the same concentrations of Brij 58 [poly(oxyethylene)20 cetyl ether] and CTAB promoted total inactivation of the enzyme. Organic solvents had different effects on lipase activity and stability. Of the tested solvents, hexane was least deleterious to lipase activity and did not alter enzyme stability on preincubation. These results suggest that Lipozyme can be used in esterification reactions with hexane as solvent or in hydrolysis reactions with Tween 20 or Tween 80 as emulsifying agents, after pretreatment with sodium cholate.

  5. MOLECULAR MODELING AND DOCKING STUDIES OF COLD ACTIVE LIPASE FROM Pseudomonas fluorescens

    Directory of Open Access Journals (Sweden)

    G. N. Gupta

    2015-03-01

    Full Text Available Molecular Modeling is essential tool in the drug design process describes the generation, manipulation or representation of 3D structures of the molecules and associated physico-chemical properties while docking predicts the preferred orientation of one molecule to a second when bound to each other to form a stable complex. A cold active lipase producing potential psychrophilic bacteria (GN was isolated and identified by 16S rRNA molecular studies as Pseudomonas vancouverensis. Lipase gene from closely related species P. fluorescens was investigated for their functional role and in silico characterization using molecular modeling and docking studies. A 3D structure of lipase gene was generated with SWISS-MODEL and Discovery Studio 3.0. The stereochemistry of the constructed model of cold active lipase was subjected to energy minimization and the stereo-chemical quality of the predicted structure was assessed. The superimposition of the template (PDBID: 2Z8X with predicted structure showed that weighted root mean square deviation of Cα trace between the template and the final refined model was 0.2 Å with a significant Zscore of 8.2 and sequence identity was 80.5%. Three ligands P-Nitrophenol, Acetate ion and Diethyl phosphonate were taken for docking calculation with generated structure. They were interacting on the functional motifs of predicted model. It has been observed that Leu26, Tyr29, Asn31, Asp33, Pro315 and Thr316 residues were involved in hydrogen bonding interactions with selected ligands. So these interacted residues can be used as prominent active binding sites and which was common to the predicted active site. Based on above investigations it has been found that P. vancouverensis lipase protein can play a similar role in lipid metabolic process and triglyceride lipase functional activity as reported for P. fluorescens lipase protein.

  6. Stimulation of Chromobacterium lipase activity and prevention of its adsorption to palmitoyl cellulose by hydrophobic binding of fatty acids.

    Science.gov (United States)

    Horiuti, Y; Imamura, S

    1978-05-01

    Fatty acids prevented adsorption of purified Chromobacterium lipase [triacylglycerol acylhydrolase, EC 3.1.1.3] onto palmitoyl cellulose (Pal-C) and also increased the activity of the purified lipase. These effects increased with increase in the concentration and chainlength (up to 16 carbon atoms) of the fatty acids, and long-chain unsaturated fatty acids, such as oleic acid, linoleic acid and erucic acid, were most effective. When the lipase was adsorbed (immobilized) on Pal-C, its activity was elevated to 20 times that of the free lipase in detergent-free reaction mixture (olive oil-buffer system). Thus lipase was adsorbed to Pal-C through a hydrophobic site distinct from its catalytic site and the binding of fatty acids to the hydrophobic site seems to result in stimulation of the lipase activity.

  7. Lipase activity and antioxidant capacity in coffee (Coffea arabica L.) seeds during germination.

    Science.gov (United States)

    Patui, Sonia; Clincon, Luisa; Peresson, Carlo; Zancani, Marco; Conte, Lanfranco; Del Terra, Lorenzo; Navarini, Luciano; Vianello, Angelo; Braidot, Enrico

    2014-04-01

    In this paper, lipase activity was characterized in coffee (Coffea arabica L.) seeds to determine its involvement in lipid degradation during germination. The lipase activity, evaluated by a colorimetric method, was already present before imbibition of seeds and was further induced during the germination process. The activity showed a biphasic behaviour, which was similar in seeds either with or without endocarp (parchment), even though the phenomenon showed a delay in the former. The enzymatic activity was inhibited by tetrahydrolipstatin (THL), a selective and irreversible inhibitor of lipases, and by a polyclonal antibody raised against purified alkaline lipase from castor bean. The immunochemical analysis evidenced a protein of ca. 60 kDa, cross-reacting with an anti-lipase antibody, in coffee samples obtained from seeds of both types. Gas chromatographic analyses of free fatty acid (FFA) content confirmed the differences shown in the lipolytic activity of the samples with or without parchment, since FFA levels increased more rapidly in samples without parchment. Finally, the analyses of the antioxidant capacity showed that the presence of parchment was crucial for lowering the oxidation of the lipophylic fraction, being the seeds with parchment less prone to oxidation processes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Lipase immobilization on epoxy-activated poly(vinyl acetate-acrylamide) microspheres.

    Science.gov (United States)

    Zhang, Dong-Hao; Peng, Li-Juan; Wang, Yun; Li, Ya-Qiong

    2015-05-01

    Poly(vinyl acetate-acrylamide) microspheres with an average diameter of 2-4μm were successfully prepared and characterized via SEM and FTIR. Then the microspheres were modified with epoxy groups through reacting with epichlorohydrin and used as carriers to covalently immobilize Candida rugosa lipase. The results revealed that agitation played an important role on epoxy activation and the immobilization ratio increased with the increase of the epoxy density. On the other hand, the specific activity of the immobilized lipase as well as the activity recovery declined gradually with the increase in the immobilization ratio from 72% to 93%, which were attributed to the steric hindrance effects caused by enzyme overloading. When epoxy density was 76μmol/g microsphere, the activity recovery reached the maximum at 47.5%, and the activity of the immobilized lipase was 261.3U/g microsphere. Moreover, the thermal stability of the immobilized lipase was much better than that of the free one, which indicated potential applications of the immobilized lipase.

  9. TLC bioautographic method for detecting lipase inhibitors.

    Science.gov (United States)

    Hassan, Abdel Moniem Sadek

    2012-01-01

    Bioautographic assays using TLC play an important role in the search for active compounds from plants. A TLC bioautographic assay has previously been established for the detection of acetylcholinesterase inhibitors but not for lipases. Development of a TLC bioautographic method for detecting lipase inhibitors in plant extracts. After migration of the plant extracts, the TLC plate was sprayed with α-naphtyl acetate and enzyme solutions before incubation at 37°C for 20 min. Finally, the solution of Fast Blue B salt was sprayed onto the TLC plate giving a purple background colouration. Lipase inhibitors were visualised as white spots on the TLC plates. Orlistat (a known lipase inhibitor) inhibited lipase down to 0.01 µg. Methanolic extracts of Camellia sinensis (L.) kuntz and Rosmarinus officinalis L after migration on TLC gave enzymatic inhibition when applied in amounts of 82 and 56 µg, respectively. On the other hand the methanolic extract of Morus alba leaves did not exhibit any lipase inhibitory activity. The screening test was able to detect lipase inhibition by pure reference substances and by compounds present in complex matrices, such as plant extracts. Copyright © 2011 John Wiley & Sons, Ltd.

  10. A gene encoding a new cold-active lipase from an Antarctic isolate of Penicillium expansum.

    Science.gov (United States)

    Mohammed, Suja; Te'o, Junior; Nevalainen, Helena

    2013-08-01

    Cold-active lipases are of significant interest as biocatalysts in industrial processes. We have identified a lipase that displayed activity towards long carbon-chain-p-nitrophenyl substrates (C12-C18) at 25 °C from the culture supernatant of an Antarctic Penicillium expansum strain assigned P. expansum SM3. Zymography revealed a protein band of around 30 kDa with activity towards olive oil. DNA fragments of a lipase gene designated as lipPE were isolated from the genomic DNA of P. expansum SM3 by genomic walking PCR. Subsequently, the complete genomic lipPE gene was amplified using gene-specific primers designed from the 5'- and 3'-regions. Reverse transcription PCR was used to amplify the lipPE cDNA. The deduced amino acid sequence consisted of 285 residues that included a predicted signal peptide. Three peptides identified by LC/MS/MS analysis of the proteins in the culture supernatant of P. expansum were also present in the deduced amino acid sequence of the lipPE gene suggesting that this gene encoded the lipase identified by initial zymogram activity analysis. Full analysis of the nucleotide and the deduced amino acid sequences indicated that the lipPE gene encodes a novel P. expansum lipase. The lipPE gene was expressed in E. coli for further characterization of the enzyme with a view of assessing its suitability for industrial applications.

  11. Hydrophobic surface modification of chitosan gels by stearyl for improving the activity of immobilized lipase

    Institute of Scientific and Technical Information of China (English)

    Hong Tao Deng; Juan Juan Wang; Miao Ma; Zhong Yang Liu; Fei Zheng

    2009-01-01

    The hydrophobic surface modification of chitosan gels was carded out using the amidating reaction of amido groups on a gel surface with steafic acid activated by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N-hydroxy-succinimide (NHS). Lipases from Candida rugosa were adsorbed on the nascent chitosan gels (CS) and stearyl-modified gels (SCS) with different degrees of amidation. The increased surface hydrophobicity of chitosan gels improved the adsorption capacity and activity of the immobilized lipase. SCS with 31.46% amidation showed the maximum activity retention (83.43%). The experimental results suggest that the moderate surface hydrophilicity/hydropbobicity of chitosan gels is necessary for the improvement of the activity of immobilized lipase.

  12. Anti- and Pro-Lipase Activity of Selected Medicinal, Herbal and Aquatic Plants, and Structure Elucidation of an Anti-Lipase Compound

    Directory of Open Access Journals (Sweden)

    Muhammad Abubakar Ado

    2013-11-01

    Full Text Available Plants that help in slowing down the digestion of triacylglycerols (TAGs in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98 medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents. Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4% exhibited moderate inhibition (41%–80% and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack I.C Nielsen L. (jering, Cynometra cauliflora (nam-nam and Aleurites moluccana (L. Willd (candle nut/buah keras had the highest (100% anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis, activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

  13. Anti- and pro-lipase activity of selected medicinal, herbal and aquatic plants, and structure elucidation of an anti-lipase compound.

    Science.gov (United States)

    Ado, Muhammad Abubakar; Abas, Faridah; Mohammed, Abdulkarim Sabo; Ghazali, Hasanah M

    2013-11-26

    Plants that help in slowing down the digestion of triacylglycerols (TAGs) in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98) medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL) activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents). Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4%) exhibited moderate inhibition (41%-80%) and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack) I.C Nielsen L. (jering), Cynometra cauliflora (nam-nam) and Aleurites moluccana (L.) Willd (candle nut/buah keras) had the highest (100%) anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis), activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

  14. A novel fluorogenic substrate for the measurement of endothelial lipase activity

    OpenAIRE

    2011-01-01

    Endothelial lipase (EL) is a phospholipase A1 (PLA1) enzyme that hydrolyzes phospholipids at the sn-1 position to produce lysophospholipids and free fatty acids. Measurement of the PLA1 activity of EL is usually accomplished by the use of substrates that are also hydrolyzed by lipases in other subfamilies such as PLA2 enzymes. In order to distinguish PLA1 activity of EL from PLA2 enzymatic activity in cell-based assays, cell supernatants, and other nonhomogeneous systems, a novel fluorogenic ...

  15. Lipase immobilized catalytically active membrane for synthesis of lauryl stearate in a pervaporation membrane reactor.

    Science.gov (United States)

    Zhang, Weidong; Qing, Weihua; Ren, Zhongqi; Li, Wei; Chen, Jiangrong

    2014-11-01

    A composite catalytically active membrane immobilized with Candida rugosa lipase has been prepared by immersion phase inversion technique for enzymatic synthesis of lauryl stearate in a pervaporation membrane reactor. SEM images showed that a "sandwich-like" membrane structure with a porous lipase-PVA catalytic layer uniformly coated on a polyvinyl alcohol (PVA)/polyethersulfone (PES) bilayer was obtained. Optimum conditions for lipase immobilization in the catalytic layer were determined. The membrane was proved to exhibit superior thermal stability, pH stability and reusability than free lipase under similar conditions. In the case of pervaporation coupled synthesis of lauryl stearate, benefited from in-situ water removal by the membrane, a conversion enhancement of approximately 40% was achieved in comparison to the equilibrium conversion obtained in batch reactors. In addition to conversion enhancement, it was also found that excess water removal by the catalytically active membrane appears to improve activity of the lipase immobilized. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. A Novel Cold-Active Lipase from Candida albicans: Cloning, Expression and Characterization of the Recombinant Enzyme

    OpenAIRE

    Dong-Ming Lan; Yong-Hua Wang; Bo Yang; Ning Yang; Wen-Kai Wang; Yan-Fei Shen

    2011-01-01

    A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM...

  17. Optimization of esterification activity of lipase from Candida rugosa immobilized using microwave irradiation

    Directory of Open Access Journals (Sweden)

    Mihailović Mladen D.

    2012-01-01

    Full Text Available Lipases are very efficient biocatalysts with wide application in synthesis of important ingredients of food, cosmetics and pharmaceutical products, due to their capacity to catalyze both, ester synthesis and ester hydrolysis. The preparation of stable and active immobilized derivatives of lipases is necessity for their application in industrial enzymatic processes. In this work, the optimization of lipase from C. rugosa immobilization by microwave irradiation was performed, since it was previously reported that immobilization process can be drastically accelerated by means of microwave irradiation, even resulting with slight increase of lipase activity. Eupergit®, commercial support with active epoxy groups, was used as immobilization support. In first stage of our study, the immobilization time and ionic strength of immobilization buffer were optimized. It was found out that the highest immobilized activity can be achieved at high ionic strengths (1 M buffer after 3 min, while further increase of immobilization time led to decrease of lipase activity. Then, the immobilized derivative obtained at optimum conditions was applied in synthesis of amyl isobutyrate in organic solvent. Key reaction factors (temperature, water concentration, immobilized lipase concentration, and substrate molar ratio were optimized using response surface methodology. The substrate conversion higher above 85% was achieved in our study. The statistical analysis revealed that each of analyzed factors had significant effect on yield of ester, with initial enzyme concentration and substrate molar ratio being the most prominent factors. The second-order regression model that describes the effect of all four factors on substrate conversion was established. The optimum values of factors were: temperature 50ºC, initial immobilized enzyme concentration 220 mg ml-1, added water concentration 0.1% (v/v, and molar ratio acid/alcohol 2.5.

  18. Monoamine oxidase inhibitory activities of heterocyclic chalcones.

    Science.gov (United States)

    Minders, Corné; Petzer, Jacobus P; Petzer, Anél; Lourens, Anna C U

    2015-11-15

    Studies have shown that natural and synthetic chalcones (1,3-diphenyl-2-propen-1-ones) possess monoamine oxidase (MAO) inhibition activities. Of particular importance to the present study is a report that a series of furanochalcones acts as MAO-B selective inhibitors. Since the effect of heterocyclic substitution, other than furan (and more recently thiophene, piperidine and quinoline) on the MAO inhibitory properties of the chalcone scaffold remains unexplored, the aim of this study was to synthesise and evaluate further heterocyclic chalcone analogues as inhibitors of the human MAOs. For this purpose, heterocyclic chalcone analogues that incorporate pyrrole, 5-methylthiophene, 5-chlorothiophene and 6-methoxypyridine substitution were examined. Seven of the nine synthesised compounds exhibited IC50 values chalcones are reversible and competitive MAO inhibitors. 4h, however, may exhibit tight-binding to MAO-B, a property linked to its thiophene moiety. We conclude that high potency chalcones such as 4h represent suitable leads for the development of MAO-B inhibitors for the treatment of Parkinson's disease and possibly other neurodegenerative disorders.

  19. Recruitment of activation receptors at inhibitory NK cell immune synapses.

    Directory of Open Access Journals (Sweden)

    Nicolas Schleinitz

    Full Text Available Natural killer (NK cell activation receptors accumulate by an actin-dependent process at cytotoxic immune synapses where they provide synergistic signals that trigger NK cell effector functions. In contrast, NK cell inhibitory receptors, including members of the MHC class I-specific killer cell Ig-like receptor (KIR family, accumulate at inhibitory immune synapses, block actin dynamics, and prevent actin-dependent phosphorylation of activation receptors. Therefore, one would predict inhibition of actin-dependent accumulation of activation receptors when inhibitory receptors are engaged. By confocal imaging of primary human NK cells in contact with target cells expressing physiological ligands of NK cell receptors, we show here that this prediction is incorrect. Target cells included a human cell line and transfected Drosophila insect cells that expressed ligands of NK cell activation receptors in combination with an MHC class I ligand of inhibitory KIR. The two NK cell activation receptors CD2 and 2B4 accumulated and co-localized with KIR at inhibitory immune synapses. In fact, KIR promoted CD2 and 2B4 clustering, as CD2 and 2B4 accumulated more efficiently at inhibitory synapses. In contrast, accumulation of KIR and of activation receptors at inhibitory synapses correlated with reduced density of the integrin LFA-1. These results imply that inhibitory KIR does not prevent CD2 and 2B4 signaling by blocking their accumulation at NK cell immune synapses, but by blocking their ability to signal within inhibitory synapses.

  20. Emulsifying triglycerides with dairy phospholipids instead of soy lecithin modulates gut lipase activity

    DEFF Research Database (Denmark)

    Mathiassen, Jakob Hovalt; Nejrup, Rikke Guldhammer; Frøkiær, Hanne

    2015-01-01

    in particular to limit fatty acid absorption in babies given infant formulas. Since interaction between the lipid droplet and the gastric and duodenal lipases occur through the hydrophobic/hydrophilic interface, the composition of the emulsifier may be crucial for efficient hydrolysis. We therefore determined...... to strategically design the surface layer of lipid droplets in infant formulas to maximize gastric lipase activity, and that this could improve total fatty acid absorption in formula-fed neonates. This is of particular importance in the development of formula aimed at pre-mature babies, but is also highly relevant...... for formulas for term-born infants....

  1. Bacterial lipases for biotechnological applications

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Schneidinger, Bernd; Rosenau, Frank; Werner, Michael; Lang, Dietmar; Dijkstra, Bauke W.; Schimossek, Klaus; Zonta, Albin; Reetz, Manfred T.

    1997-01-01

    Lipase genes originating from the Gram-negative bacteria Serrutiu marcescens and Pseudomonus urruginosa were cloned. S. marcescens lipase was overexpressed in Escherichia coli yielding inclusion bodies which were purified and finally refolded to give enzymatically active lipase. The lipase operon of

  2. Atorvastatin dose-dependently decreases hepatic lipase activity in type 2 diabetes - Effect of sex and the LIPC promoter variant

    NARCIS (Netherlands)

    Berk-Planken, IIL; Hoogerbrugge, N; Stolk, RP; Bootsma, AH; Jansen, H

    2003-01-01

    OBJECTIVE - Hepatic lipase (HL) is involved in the metabolism of several lipoproteins and may contribute to the atherogenic lipid profile in type 2 diabetes. Little is known about the effect of cholesterol synthesis inhibitors on HL activity in relation to sex and the hepatic lipase gene, the LIPC p

  3. Smart conjugated polymer nanocarrier for healthy weight loss by negative feedback regulation of lipase activity

    Science.gov (United States)

    Chen, Yu-Lei; Zhu, Sha; Zhang, Lei; Feng, Pei-Jian; Yao, Xi-Kuang; Qian, Cheng-Gen; Zhang, Can; Jiang, Xi-Qun; Shen, Qun-Dong

    2016-02-01

    Healthy weight loss represents a real challenge when obesity is increasing in prevalence. Herein, we report a conjugated polymer nanocarrier for smart deactivation of lipase and thus balancing calorie intake. After oral administration, the nanocarrier is sensitive to lipase in the digestive tract and releases orlistat, which deactivates the enzyme and inhibits fat digestion. It also creates negative feedback to control the release of itself. The nanocarrier smartly regulates activity of the lipase cyclically varied between high and low levels. In spite of high fat diet intervention, obese mice receiving a single dose of the nanocarrier lose weight over eight days, whereas a control group continues the tendency to gain weight. Daily intragastric administration of the nanocarrier leads to lower weight of livers or fat pads, smaller adipocyte size, and lower total cholesterol level than that of the control group. Near-infrared fluorescence of the nanocarrier reveals its biodistribution.Healthy weight loss represents a real challenge when obesity is increasing in prevalence. Herein, we report a conjugated polymer nanocarrier for smart deactivation of lipase and thus balancing calorie intake. After oral administration, the nanocarrier is sensitive to lipase in the digestive tract and releases orlistat, which deactivates the enzyme and inhibits fat digestion. It also creates negative feedback to control the release of itself. The nanocarrier smartly regulates activity of the lipase cyclically varied between high and low levels. In spite of high fat diet intervention, obese mice receiving a single dose of the nanocarrier lose weight over eight days, whereas a control group continues the tendency to gain weight. Daily intragastric administration of the nanocarrier leads to lower weight of livers or fat pads, smaller adipocyte size, and lower total cholesterol level than that of the control group. Near-infrared fluorescence of the nanocarrier reveals its biodistribution

  4. Identification and Characterization of Lipase Activity and Immunogenicity of LipL from Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Jun Cao

    Full Text Available Lipids and lipid-metabolizing esterases/lipases are highly important for the mycobacterial life cycle and, possibly, for mycobacterial virulence. In this study, we expressed 10 members of the Lip family of Mycobacterium tuberculosis. Among the 10 proteins, LipL displayed a significantly high enzymatic activity for the hydrolysis of long-chain lipids. The optimal temperature for the lipase activity of LipL was demonstrated to be 37°C, and the optimal pH was 8.0. The lipase active center was not the conserved motif G-x-S-x-G, but rather the S-x-x-K and GGG motifs, and the key catalytic amino acid residues were identified as G50, S88, and K91, as demonstrated through site-directed mutagenesis experiments. A three-dimensional modeling structure of LipL was constructed, which showed that the GGG motif was located in the surface of a pocket structure. Furthermore, the subcellular localization of LipL was demonstrated to be on the mycobacterial surface by Western blot analysis. Our results revealed that the LipL protein could induce a strong humoral immune response in humans and activate a CD8+ T cell-mediated response in mice. Overall, our study identified and characterized a novel lipase denoted LipL from M. tuberculosis, and demonstrated that LipL functions as an immunogen that activates both humoral and cell-mediated responses.

  5. Substitution of Val72 residue alters the enantioselectivity and activity of Penicillium expansum lipase.

    Science.gov (United States)

    Tang, Lianghua; Su, Min; Zhu, Ling; Chi, Liying; Zhang, Junling; Zhou, Qiong

    2013-01-01

    Error-prone PCR was used to create more active or enantioselective variants of Penicillium expansum lipase (PEL). A variant with a valine to glycine substitution at residue 72 in the lid structure exhibited higher activity and enantioselectivity than those of wild-type PEL. Site-directed saturation mutagenesis was used to explore the sequence-function relationship and the substitution of Val72 of P. expansum lipase changed both catalytic activity and enantioselectivity greatly. The variant V72A, displayed a highest enantioselectivity enhanced to about twofold for the resolution of (R, S)-naproxen (E value increased from 104 to 200.7 for wild-type PEL and V72A variant, respectively). In comparison to PEL, the variant V72A showed a remarkable increase in specific activity towards p-nitrophenyl palmitate (11- and 4-fold increase at 25 and 35 °C, respectively) whereas it had a decreased thermostability. The results suggest that the enantioselective variant V72A could be used for the production of pharmaceutical drugs such as enantiomerically pure (S)-naproxen and the residue Val 72 of P. expansum lipase plays a significant role in the enantioselectivity and activity of this enantioselective lipase.

  6. A new approach to determine the stereospecificity in lipase catalysed hydrolysis using circular dichroism (CD): lipases produce optically active diglycerides from achiral triglycerides.

    Science.gov (United States)

    Uzawa, H; Nishida, Y; Ohrui, H; Meguro, H

    1990-04-30

    We describe a sensitive CD method for determining the stereospecificity in lipase (E.C.3.1.1.3) catalysed hydrolysis of triacyl glycerols into diacyl glycerols. The diglycerols were converted to chiral tert-butyldimethylsilylated 1,2- or 2,3-di-O-benzoyl-sn-glycerol (5 or 5'), and their CD was measured. This approach showed for the first time that lipases produce optically active diacyl glycerides from achiral tripalmitin and tribenzoyl glyceride with a variable extent of enantioselectivity depending on the acyl groups and the enzymes.

  7. Muscle triacylglycerol and hormone-sensitive lipase activity in untrained and trained human muscles

    DEFF Research Database (Denmark)

    Helge, Jørn Wulff; Biba, Taus O; Galbo, Henrik

    2006-01-01

    During exercise, triacylglycerol (TG) is recruited in skeletal muscles. We hypothesized that both muscle hormone-sensitive lipase (HSL) activity and TG recruitment would be higher in trained than in untrained subjects in response to prolonged exercise. Healthy male subjects (26 +/- 1 years, body ...

  8. Liver and extrahepatic contributions to postheparin serum lipase activity of the rat

    NARCIS (Netherlands)

    H. Jansen (Hans); W.C. Hülsmann (William)

    1974-01-01

    textabstractThe influence of the amount of heparin injected on the contributions of liver and of extrahepatic tissues to the lipase activity of postheparin serum of the rat was studied. It was found that when high doses of heparin (20 I.U./100 g bodyweight) were injected, the liver contributes for 6

  9. Effects of Polyelectrolyte Complex Micelles and Their Components on the Enzymatic Activity of Lipase

    NARCIS (Netherlands)

    Lindhoud, Saskia; Norde, Willem; Stuart, Martien Cohen

    2010-01-01

    The enzymatic activity of Hi-lipase embedded in complexes of poly-2-methylvinylpyridinium-co-poly(ethylene oxide) (P2MVP(41)-PEG(205)) and poly(acrylic acid)(PAA(139)) is studied as a function of the PAA(139) + P2MVP(41) - PEO(205) complex composition. The measurements revealed that there are severa

  10. Effects of Different Dietary Lipid Contents on Growth and Lipase Activity of Eriocheir sinensis Larvae

    Institute of Scientific and Technical Information of China (English)

    ZHENG Debin; PAN Luqing; FANG Bo

    2011-01-01

    The effects of different dietary lipid content on the growth and lipase activity ofEriocheir sinensis larvae were studied in the paper.The results showed that the survival,metamorphic rate and weight gain ofE.sinensis larvae at different stages of growth all varied significantly with lipid content(P<0.05).Further,the survival and metamorphosis rates were the highest during the larval phases Z3 to Z4,and the weight gain was the highest during the larval phases Z5 to M.During the first 20h after metamorphosis of every larval stage,the lipase activity increased over time at Z1,Z2,Z3 and M and declined at Z4 and Z5,and was influenced significantly by lipid content(P<0.05).In addition,lipase activity at each larval stage began to respond to dietary lipid contents 4h after the larvae were fed,and tended to be stable after 12 h.The diets with higher lipase activity and lower lipid content were selected to give the suitable recipe of lipid requirements at each larval stage.It was concluded that the suitable lipid requirements at Z1,Z2,Z3,Z4,Z5 and M were 6%,4%,6%,8%,8% and 10%,respectively.

  11. Effect of Water Clustering on the Activity of Candida antarctica Lipase B in Organic Medium

    DEFF Research Database (Denmark)

    Banik, Sindrila Dutta; Nordblad, Mathias; Woodley, John M.

    2017-01-01

    The effect of initial water activity of MTBE (methyl tert-butyl ether) medium on CALB (Candida antarctica lipase B) catalyzed esterification reaction is investigated using experimental methods and classical molecular dynamics (MD) simulations. The experimental kinetic studies show that the initial...

  12. Liver and extrahepatic contributions to postheparin serum lipase activity of the rat

    NARCIS (Netherlands)

    H. Jansen (Hans); W.C. Hülsmann (William)

    1974-01-01

    textabstractThe influence of the amount of heparin injected on the contributions of liver and of extrahepatic tissues to the lipase activity of postheparin serum of the rat was studied. It was found that when high doses of heparin (20 I.U./100 g bodyweight) were injected, the liver contributes for

  13. Purification and characterization of a new cold active lipase, EnL A ...

    African Journals Online (AJOL)

    SDS PAGE analysis revealed that the protein is monomeric with a MW of ˜54 kDa ... revealed that the temperature optimum was at 30°C and an optimum pH of 5. ... Key words: Cold active lipase, Emericella nidulans, hydrophobic interaction ...

  14. Secretion and apparent activation of human hepatic lipase requires proper oligosaccharide processing in the endoplasmic reticulum

    NARCIS (Netherlands)

    A.J.M. Verhoeven (Adrie); B.P. Neve (Bernadette); H. Jansen (Hans)

    1999-01-01

    textabstractHuman hepatic lipase (HL) is a glycoprotein with four N-linked oligosaccharide side chains. The importance of glycosylation for the secretion of catalytically active HL was studied in HepG2 cells by using inhibitors of intracellular trafficking, N-glycosylat

  15. Effects of lipid-borne compounds on the activity and stability of lipases in micro-aqueous systems for lipase-catalyzed reaction

    DEFF Research Database (Denmark)

    Xu, Xuebing; Høy, Carl-Erik; Adler-Nissen, Jens

    1998-01-01

    In this paper, the effects of lipid-borne compounds such as lipid hydroperoxides, lipid polymers, phospholipids and emulsifiers, chlorophyll and carotenoids, tocopherols, citric acid, partial glycerides and free fatty acids on the activity and stability of lipases are discussed. Generally...

  16. Synthesis of monoacylglycerol containing pinolenic acid via stepwise esterification using a cold active lipase.

    Science.gov (United States)

    Pyo, Young-Gil; Hong, Seung In; Kim, Yangha; Kim, Byung Hee; Kim, In-Hwan

    2012-01-01

    High purity monoacylglycerol (MAG) containing pinolenic acid was synthesized via stepwise esterification of glycerol and fatty acids from pine nut oil using a cold active lipase from Penicillium camembertii as a biocatalyst. Effects of temperature, molar ratio, water content, enzyme loading, and vacuum on the synthesis of MAG by lipase-catalyzed esterification of glycerol and fatty acid from pine nut oil were investigated. Diacylglycerol (DAG) as well as MAG increased significantly when temperature was increased from 20 to 40 °C. At a molar ratio of 1:1, MAG content decreased because of the significant increase in DAG content. Water has a profound influence on both MAG and DAG content through the entire course of reaction. The reaction rate increased significantly as enzyme loading increased up to 600 units. Vacuum was an effective method to reduce DAG content. The optimum temperature, molar ratio, water content, enzyme loading, vacuum, and reaction time were 20 °C, 1:5 (fatty acid to glycerol), 2%, 600 units, 5 torr, and 24 h, respectively. MAG content further increased via lipase-catalyzed second step esterification at subzero temperature. P. camembertii lipase exhibited esterification activity up to -30 °C.

  17. Immobilization of Yarrowia lipolytica lipase Ylip2 for the biocatalytic synthesis of phytosterol ester in a water activity controlled reactor.

    Science.gov (United States)

    Cui, Caixia; Guan, Nan; Xing, Chen; Chen, Biqiang; Tan, Tianwei

    2016-10-01

    In this work, phytosterol ester was synthesized using Yarrowia lipolytica lipase Ylip2 that had been immobilized on inorganic support in a solvent-free system and reacted in a computer-aided water activity controlled bioreactor. The immobilization of Ylip2 on celite led to a remarkable increase in the phytosterol conversion compared to that of free lipase. An investigation of the reaction conditions were oleic acid as the fatty acid variety, 10,000U/g substrate, and a temperature of 50°C for phytosterol ester synthesis. Controlling of the water activity at a set point was accomplished by the introduction of dry air through the reaction medium at a digital feedback controlled flow rate. For the esterification of phytosterol ester, a low (15%) water activity resulted in a considerable improvement in phytosterol conversion (91.1%) as well as a decreased reaction time (78h). Furthermore, Ylip2 lipase immobilized on celite retained 90% esterification activity for the synthesis of phytosterol oleate after reused 8 cycles, while free lipase was only viable for 5 batches with 90% esterification activity remained. Finally, the phytosterol oleate space time yield increased from 1.65g/L/h with free lipase to 2.53g/L/h with immobilized lipase. These results illustrate that the immobilized Yarrowia lipolytica lipase Ylip2 in a water activity controlled reactor has great potential for the application in phytosterol esters synthesis.

  18. Xanthine oxidase inhibitory activity of Hungarian wild-growing mushrooms.

    Science.gov (United States)

    Ványolós, Attila; Orbán-Gyapai, Orsolya; Hohmann, Judit

    2014-08-01

    Mushrooms represent a remarkable and yet largely unexplored source of new, biologically active natural products. In this work, we report on the xanthine oxidase (XO) inhibitory activity of 47 wild-growing mushrooms native to Hungary. Aqueous and organic (n-hexane, chloroform, and 50% methanol) extracts of selected mushrooms from different families were screened for their XO inhibitory activities. Among the 188 extracts investigated, the chloroform and 50% methanol fractions proved to be the most effective. Some species exhibited high inhibitory activity, e.g., Hypholoma fasciculare (IC50  =67.76 ± 11.05 µg/mL), Suillus grevillei (IC50  =13.28 ± 1.58 µg/mL), and Tricholoma populinum (IC50  =85.08 ± 15.02 µg/mL); others demonstrated moderate or weak activity. Additional studies are warranted to characterize the compounds responsible for the XO inhibitory activity of mushroom extracts.

  19. Role of lipase from community-associated methicillin-resistant Staphylococcus aureus strain USA300 in hydrolyzing triglycerides into growth-inhibitory free fatty acids.

    Science.gov (United States)

    Cadieux, Brigitte; Vijayakumaran, Vithooshan; Bernards, Mark A; McGavin, Martin J; Heinrichs, David E

    2014-12-01

    Part of the human host innate immune response involves the secretion of bactericidal lipids on the skin and delivery of triglycerides into abscesses to control invading pathogens. Two Staphylococcus aureus lipases, named SAL1 and SAL2, were identified in the community-associated methicillin-resistant S. aureus strain USA300, which, presumably, are produced and function to degrade triglycerides to release free fatty acids. We show that the SAL2 lipase is one of the most abundant proteins secreted by USA300 and is proteolytically processed from the 72-kDa proSAL2 to the 44-kDa mature SAL2 by the metalloprotease aureolysin. We show that spent culture supernatants had lipase activity on both short- and long-chain fatty acid substrates and that deletion of gehB, encoding SAL2, resulted in the complete loss of these activities. With the use of gas chromatography-mass spectrometry, we show that SAL2 hydrolyzed trilinolein to linoleic acid, a fatty acid with known antistaphylococcal properties. When added to cultures of USA300, trilinolein and, to a lesser extent, triolein inhibited growth in a SAL2-dependent manner. This effect was shown to be due to the enzymatic activity of SAL2 on these triglycerides, since the catalytically inactive SAL2 Ser412Ala mutant was incapable of hydrolyzing the triglycerides or yielding delayed growth in their presence. Overall, these results reveal that SAL2 hydrolyzes triglycerides of both short- and long-chain fatty acids and that the released free fatty acids have the potential to cause significant delays in growth, depending on the chemical nature of the free fatty acid.

  20. Modification of serum, pancreatic, and microbial lipase activities by phorbol diesters.

    Science.gov (United States)

    Zhang, Z C; Cabot, M C

    1987-01-01

    The influence of phorbol diesters on the in vitro hydrolysis of diacylglycerols was examined using enzymes from rat serum, porcine pancreas, and Rhizopus delemar. Two main phenomena were observed: 12-O-tetradecanoylphorbol-13-acetate (TPA), when added to the enzyme assay system, stimulated 2- to 3-fold the hydrolysis of [9,10-3H]dioleoylglycerol by serum lipase. The hydrolysis of dioleoylglycerol by either pancreatic or R. delemar lipase was, on the other hand, inhibited by TPA. A 50% inhibition of the pancreatic and R. delemar enzymes was attained with 10 and 2.0 microM TPA, respectively. The pattern of enzyme stimulation (rat serum), with regard to increasing TPA concentrations, was hyperbolic. Stimulation was not influenced by Triton X-100, but it was highly dependent on the structure of the phorbol ester: TPA greater than phorbol didecanoate greater than tetradecanoylphorbol. Phorbol dibutyrate, phorbol acetate, myristic acid, and mezerein were without influence. Lipase activity was inhibited most strongly by TPA and the nonpromoter 4-O-methyl-TPA; the weaker promoter, phorbol dibutyrate, was relatively inactive. The inhibition of R. delemar lipase by TPA was reversible. Collectively, these data show that phorbol diesters can interact with enzymes other than protein kinase C. It is believed, by virtue of their structural similarity to diacylglycerols, that phorbol diesters may serve directly as intracellular regulators of lipid metabolism. In such a manner phorbol esters could sustain or attenuate the second messenger signal by modifying diacylglycerol metabolism, a manifestation of the pleiotropic action.

  1. Expression of a Deschampsia antarctica Desv. Polypeptide with Lipase Activity in a Pichia pastoris Vector

    Directory of Open Access Journals (Sweden)

    Claudia Rabert

    2014-02-01

    Full Text Available The current study isolated and characterized the Lip3F9 polypeptide sequence of Deschampsia antarctica Desv. (GeneBank Accession Number JX846628, which was found to be comprised of 291 base pairs and was, moreover, expressed in Pichia pastoris X-33 cells. The enzyme was secreted after 24 h of P. pastoris culture incubation and through induction with methanol. The expressed protein showed maximum lipase activity (35 U/L with an optimal temperature of 37 °C. The lipase-expressed enzyme lost 50% of its specific activity at 25 °C, a behavior characteristic of a psychrotolerant enzyme. Recombinant enzyme activity was measured in the presence of ionic and non-ionic detergents, and a decrease in enzyme activity was detected for all concentrations of ionic and non-ionic detergents assessed.

  2. Sulforaphane induced adipolysis via hormone sensitive lipase activation, regulated by AMPK signaling pathway.

    Science.gov (United States)

    Lee, Ju-Hee; Moon, Myung-Hee; Jeong, Jae-Kyo; Park, Yang-Gyu; Lee, You-Jin; Seol, Jae-Won; Park, Sang-Youel

    2012-10-05

    Sulforaphane, an aliphatic isothiocyanate derived from cruciferous vegetables, is known for its antidiabetic properties. The effects of sulforaphane on lipid metabolism in adipocytes are not clearly understood. Here, we investigated whether sulforaphane stimulates lipolysis. Mature adipocytes were incubated with sulforaphane for 24h and analyzed using a lipolysis assay which quantified glycerol released into the medium. We investigated gene expression of hormone-sensitive lipase (HSL), and levels of HSL phosphorylation and AMP-activated protein kinase on sulforaphane-mediated lipolysis in adipocytes. Sulforaphane promoted lipolysis and increased both HSL gene expression and HSL activation. Sulforaphane suppressed AMPK phosphorylation at Thr-172 in a dose-dependent manner, which was associated with a decrease in HSL phosphorylation at Ser-565, enhancing the phosphorylation of HSL Ser-563. Taken together, these results suggest that sulforaphane promotes lipolysis via hormone sensitive lipase activation mediated by decreasing AMPK signal activation in adipocytes. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Effect of salt solutions applied during wheat conditioning on lipase activity and lipid stability of whole wheat flour.

    Science.gov (United States)

    Doblado-Maldonado, Andrés F; Arndt, Elizabeth A; Rose, Devin J

    2013-09-01

    Lipolytic activity in whole wheat flour (WWF) is largely responsible for the loss in baking quality during storage. Metal ions affect the activity of seed lipases; however, no previous studies have applied this information to WWF in a way that reduces lipase activity, is practical for commercial manufacture, and uses common food ingredients. NaCl, KCl, Ca-propionate, or FeNa-ethylenediaminetetraacetic acid (FeNa-EDTA) were applied to hard red winter (HRW) and hard white spring (HWS) wheats during conditioning as aqueous solutions at concentrations that would be acceptable in baked goods. Salts affected lipase activity to different degrees depending on the type of wheat used. Inhibition was greater in HRW compared with HWS WWF, probably due to higher lipase activity in HRW wheat. In HRW WWF, 1% NaCl (flour weight) reduced hydrolytic and oxidative rancidity and resulted in higher loaf volume and lower firmness than untreated WWF after 24 weeks of storage.

  4. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle

    DEFF Research Database (Denmark)

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel

    2010-01-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose...... HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid...

  5. Media formulation using complex organic nutrients for improved activity, productivity, and yield of Candida rugosa lipase and esterase enzymes.

    Science.gov (United States)

    Takac, Serpil; Erdem, Banu

    2009-01-01

    Candida rugosa is an excellent source of multiple lipase and esterase enzymes; therefore, it is of technological importance to formulate the medium that provides high activity for each enzyme. In this work, the cultivation medium comprising complex nutrients that provided the highest activity, productivity, and yield of C. rugosa enzymes individually was formulated. Time courses of the extracellular and intracellular lipase and esterase activities of C. rugosa were represented and the role of protease in the cultivation progress was discussed. Urea, soy-peptone, yeast extract, a mixture of soy-peptone and yeast extract, cheese whey, and wheat mill bran were tested for their lipolytic and esterasic activities. Urea provided considerably higher extracellular lipase activity when compared to other nitrogen sources; however, soy-peptone provided the highest extracellular esterase activity. Hazelnut, olive, sesame, soybean, and flax seed oils affected the enzyme activities to different extents related to their fatty acid compositions. Hazelnut oil and olive oil provided the highest extracellular lipase and esterase activities, respectively, whereas sesame oil produced the highest biomass. High C(18) and C(16) ester contents of vegetable oils promoted high lipase and esterase productions, respectively. A temperature of 30 degrees C yielded the highest extracellular and intracellular lipase and esterase activities; however, 35 degrees C produced the highest biomass.

  6. [Influence of rapeseed oil on lipoprotein lipase activity in pigs (author's transl)].

    Science.gov (United States)

    Simonetti, M S

    1976-01-01

    Toxic activities in various animal species have shown for rapeseed oil. In this paper the influence of this oil on lipoprotein lipase activity of heart, liver and lung of pigs has been examined. The animals were fed with rapeseed oil with 40% erucic acid for 7, 15, 20 and 40 days. The control animals received olive oil. The results have shown a slight increase in the lipoprotein lipase activity in the heart of the pig after 20 days with rapeseed oil. In the liver this increase is particularly large in the pigs having been fed for 15 days both with rapeseed oil and olive oil. No differences were observed in the lung in the test and control animals with the only exception of animals fed for 20 days.

  7. Global optogenetic activation of inhibitory interneurons during epileptiform activity.

    Science.gov (United States)

    Ledri, Marco; Madsen, Marita Grønning; Nikitidou, Litsa; Kirik, Deniz; Kokaia, Merab

    2014-02-26

    Optogenetic techniques provide powerful tools for bidirectional control of neuronal activity and investigating alterations occurring in excitability disorders, such as epilepsy. In particular, the possibility to specifically activate by light-determined interneuron populations expressing channelrhodopsin-2 provides an unprecedented opportunity of exploring their contribution to physiological and pathological network activity. There are several subclasses of interneurons in cortical areas with different functional connectivity to the principal neurons (e.g., targeting their perisomatic or dendritic compartments). Therefore, one could optogenetically activate specific or a mixed population of interneurons and dissect their selective or concerted inhibitory action on principal cells. We chose to explore a conceptually novel strategy involving simultaneous activation of mixed populations of interneurons by optogenetics and study their impact on ongoing epileptiform activity in mouse acute hippocampal slices. Here we demonstrate that such approach results in a brief initial action potential discharge in CA3 pyramidal neurons, followed by prolonged suppression of ongoing epileptiform activity during light exposure. Such sequence of events was caused by massive light-induced release of GABA from ChR2-expressing interneurons. The inhibition of epileptiform activity was less pronounced if only parvalbumin- or somatostatin-expressing interneurons were activated by light. Our data suggest that global optogenetic activation of mixed interneuron populations is a more effective approach for development of novel therapeutic strategies for epilepsy, but the initial action potential generation in principal neurons needs to be taken in consideration.

  8. Probiotic in rennet paste can affect lipase activity of rennet and lipolysis in ovine cheese

    Directory of Open Access Journals (Sweden)

    Marzia Albenzio

    2010-01-01

    Full Text Available Lambs were subjected to three different feeding regimes (mother suckling MS, artificial rearing AR, and artificial rearing with 7log10 cfu/ml Lactobacillus acidophilus supplementation to the milk substitute ARLb and slaughtered at 20d and 40d of age for each feeding treatment. Lambs abomasa were processed to rennet paste and lipases activity was evaluated. Rennet paste was used for Pecorino cheese production. Free fatty acids (FFAs and conjugated linoleic acids (CLAs were detected in cheese at 60d of ripening. Lipase activity was found higher in ARLb than in MS and AR rennet from lambs slaughtered at an older age. A reduction of all FFAs was observed in all cheeses when passing from 20 d to 40d of slaughtering. CLAs were more abundant in ARLb cheeses at both 20 and 40d. Milk substitute with Lb. acidophilus improves enzymatic features of rennet, and health and nutritional characteristics of ovine cheese.

  9. Lipase-mediated lipid removal from propolis extract and its antiradical and antimicrobial activity.

    Science.gov (United States)

    Park, Hyein; Bae, Song Hwan; Park, Yooheon; Choi, Hyeon-Son; Suh, Hyung Joo

    2015-06-01

    Propolis contains many antioxidants such as polyphenols and flavonoids. However, propolis-derived lipid components interrupt an efficient isolation of antioxidants from propolis extract. We examined the effectiveness of various lipase treatments for the removal of lipids from propolis extract and evaluated the biological features of the extract. Lipase OF and Novozyme 435 treatments did not reduce fatty acid level in propolis extract. However, Lipozyme TL IM-treated propolis extract showed a significant decrease in fatty acid level, suggesting the removal of lipids. Lipozyme RM IM also significantly decreased the fatty acid level of the extract, but was accompanied by the reduction of polyphenols and flavonoids, which are antioxidants. In Lipozyme TL IM treatment, an increase in active flavonoids, such as Artepillin C and kaempferide, was observed, with a slight increase of ferric reducing/antioxidant power (FRAP) radical-scavenging activity. In addition, antimicrobial activity towards skin health-related bacteria such as Staphylococcus epidermidis and Propionibacterium acnes was enhanced by Lipozyme TL IM treatment. Lipozyme TL IM treatment effectively removes lipids from propolis extract and enhances antibacterial activity. Therefore, we suggest that Lipozyme TL IM is a useful lipase for lipid removal of propolis extract. © 2014 Society of Chemical Industry.

  10. Expression, purification and characterization of a functional, recombinant, cold-active lipase (LipA) from psychrotrophic Yersinia enterocolitica.

    Science.gov (United States)

    Ji, Xiuling; Li, Shan; Wang, Baoqiang; Zhang, Qi; Lin, Lianbing; Dong, Zhiyang; Wei, Yunlin

    2015-11-01

    A novel cold-active lipase gene encoding 294 amino acid residues was obtained from the Yersinia enterocolitica strain KM1. Sequence alignment and phylogenetic analysis revealed that this novel lipase is a new member of the bacterial lipase family I.1. The lipase shares the conserved GXSXG motif and catalytic triad Ser85-Asp239-His261. The recombinant protein LipA was solubly and heterogeneously expressed in Escherichia coli, purified by Ni-affinity chromatography, and then characterized. LipA was active over a broad range spanning 15-60°C with an optimum activity at 25°C and across a wide pH range from 5.0 to 11.0 with an optimum activity at pH 7.5. The molecular weight was estimated to be 34.2 KDa. The lipase could be activated by Mg(2+) and a low concentration (10%) of ethanol, dimethyl sulfoxide, methanol and acetonitrile, whereas it was strongly inhibited by Zn(2+), Cu(2+) and Mn(2+). This cold-active lipase may be a good candidate for detergents and biocatalysts at low temperature.

  11. Retinal pigment epithelial acid lipase activity and lipoprotein receptors: effects of dietary omega-3 fatty acids.

    OpenAIRE

    2002-01-01

    PURPOSE: To show that fish oil-derived omega-3 polyunsaturated fatty acids, delivered to the retinal pigment epithelium (RPE) by circulating low-density lipoproteins (LDL), enhance already considerable RPE lysosomal acid lipase activity, providing for more efficient hydrolysis of intralysosomal RPE lipids, an effect that may help prevent development of age-related macular degeneration (ARMD). METHODS: Colorimetric biochemical and histochemical techniques were used to demonstrate RPE acid lipa...

  12. Immobilization of lipases on alkyl silane modified magnetic nanoparticles: effect of alkyl chain length on enzyme activity.

    Directory of Open Access Journals (Sweden)

    Jiqian Wang

    Full Text Available BACKGROUND: Biocatalytic processes often require a full recycling of biocatalysts to optimize economic benefits and minimize waste disposal. Immobilization of biocatalysts onto particulate carriers has been widely explored as an option to meet these requirements. However, surface properties often affect the amount of biocatalysts immobilized, their bioactivity and stability, hampering their wide applications. The aim of this work is to explore how immobilization of lipases onto magnetite nanoparticles affects their biocatalytic performance under carefully controlled surface modification. METHODOLOGY/PRINCIPAL FINDINGS: Magnetite nanoparticles, prepared through a co-precipitation method, were coated with alkyl silanes of different alkyl chain lengths to modulate their surface hydrophobicity. Candida rugosa lipase was then directly immobilized onto the modified nanoparticles through hydrophobic interaction. Enzyme activity was assessed by catalytic hydrolysis of p-nitrophenyl acetate. The activity of immobilized lipases was found to increase with increasing chain length of the alkyl silane. Furthermore, the catalytic activities of lipases immobilized on trimethoxyl octadecyl silane (C18 modified Fe(3O(4 were a factor of 2 or more than the values reported from other surface immobilized systems. After 7 recycles, the activities of the lipases immobilized on C18 modified nanoparticles retained 65%, indicating significant enhancement of stability as well through hydrophobic interaction. Lipase immobilized magnetic nanoparticles facilitated easy separation and recycling with high activity retaining. CONCLUSIONS/SIGNIFICANCE: The activity of immobilized lipases increased with increasing alkyl chain length of the alkyl trimethoxy silanes used in the surface modification of magnetite nanoparticles. Lipase stability was also improved through hydrophobic interaction. Alkyl silane modified magnetite nanoparticles are thus highly attractive carriers for

  13. Influence of N- and/or C-terminal regions on activity, expression, characteristics and structure of lipase from Geobacillus sp. 95.

    Science.gov (United States)

    Gudiukaitė, Renata; Gegeckas, Audrius; Kazlauskas, Darius; Citavicius, Donaldas

    2014-01-01

    GD-95 lipase from Geobacillus sp. strain 95 and its modified variants lacking N-terminal signal peptide and/or 10 or 20 C-terminal amino acids were successfully cloned, expressed and purified. To our knowledge, GD-95 lipase precursor (Pre-GD-95) is the first Geobacillus lipase possessing more than 80% lipolytic activity at 5 °C. It has maximum activity at 55 °C and displays a broad pH activity range. GD-95 lipase was shown to hydrolyze p-NP dodecanoate, tricaprylin and canola oil better than other analyzed substrates. Structural and sequence alignments of bacterial lipases and GD-95 lipase revealed that the C-terminus forms an α helix, which is a conserved structure in lipases from Pseudomonas, Clostridium or Staphylococcus bacteria. This work demonstrates that 10 and 20 C-terminal amino acids of GD-95 lipase significantly affect stability and other physicochemical properties of this enzyme, which has never been reported before and can help create lipases with more specific properties for industrial application. GD-95 lipase and its modified variants GD-95-10 can be successfully applied to biofuel production, in leather and pulp industries, for the production of cosmetics or perfumes. These lipases are potential biocatalysts in processes, which require extreme conditions: low or high temperature, strongly acidic or alkaline environment and various organic solvents.

  14. Increasing the activity and enantioselectivity of lipases by sol-gel immobilization: further advancements of practical interest.

    Science.gov (United States)

    Tielmann, Patrick; Kierkels, Hans; Zonta, Albin; Ilie, Adriana; Reetz, Manfred T

    2014-06-21

    The entrapment of lipases in hydrophobic silicate matrices formed by sol-gel mediated hydrolysis of RSi(OCH3)3/Si(OCH3)4 as originally reported in 1996 has been improved over the years by a number of modifications. In the production of second-generation sol-gel lipase immobilizates, a variety of additives during the sol-gel process leads to increased activity and enhanced stereoselectivity in esterifying kinetic resolution. Recent advances in this type of lipase immobilization are reviewed here, in addition to new results regarding the sol-gel entrapment of the lipase from Burkholderia cepacia. It constitutes an excellent heterogeneous biocatalyst in the acylating kinetic resolution of two synthetically and industrially important chiral alcohols, rac-sulcatol and rac-trans-2-methoxycyclohexanol. The observation that the catalyst can be used 10 times in recycling experiments without losing its significant activity or enantioselectivity demonstrates the practical viability of the sol-gel approach.

  15. Inhibition of key enzymes linked to obesity by preparations from Mediterranean dietary plants: effects on α-amylase and pancreatic lipase activities.

    Science.gov (United States)

    2013-12-01

    One of the most important strategy in the treatment of obesity includes the development of nutrient digestion and absorption inhibitors. Inhibition of digestive enzymes is one of the most widely studied mechanisms used to determine the potential efficacy of natural products as hypolipidemic and hypoglycaemic agents. In vitro studies here reported were performed to evaluate the inhibitory activity of five species(as hydroalcoholic extracts) of edible plants from Calabria region (Italy) on amylase and lipase by monitoring the hydrolysis of p-NPC and the hydrolysis of glycoside bonds indigestible carbohydrate foods. The formulation obtained from Clematis vitalba L. exhibited the strongest inhibitory effect on pancreatic lipase (IC50=0.99 mg/ml) and on α-amylase(IC50=31.52 μg/ml). In order to explore metabolome production HPTLC analysis of the extracts was performed, revealing the predominance of (±)-catechin, caffeic acid and chlorogenic acid in C. vital ba formulation at concentration of 23.18±3.14,13.63±0.65 and 18.88±0.76 mg/g, respectively. GC/MS analysis was used to identify fatty acids and terpene composition.

  16. Complement inhibitory and anticoagulant activities of fractionated heparins

    NARCIS (Netherlands)

    Hennink, W.E.; Klerx, J.P.A.M.; Dijk, H. van; Feijen, J.

    1984-01-01

    Almost monodisperse heparin fractions (w/n < 1.1) were obtained by gel filtration of a commercial heparin. These fractions were assayed for anticoagulant activity (thrombin times and APTT), chromogenic anti-factor Xa activity, inhibitory activity for the human classical complement pathway, carboxyl

  17. Liquid crystal based sensors monitoring lipase activity: a new rapid and sensitive method for cytotoxicity assays.

    Science.gov (United States)

    Hussain, Zakir; Zafiu, Christian; Küpcü, Seta; Pivetta, Lucineia; Hollfelder, Nadine; Masutani, Akira; Kilickiran, Pinar; Sinner, Eva-Kathrin

    2014-06-15

    In this work we present liquid crystal (LC) based sensor devices to monitor cell viability. The sensing layer is composed by the LC and a planar monolayer of phospholipids. In the presence of minute traces of phospholipases, which hydrolyze enzymatically phospholipids, the LC-lipid interface is disintegrated. This event causes a change in orientation of the LC, which was followed in a polarized microscope. The lipase activity can be used to measure the cell viability, since members of this enzyme family are released by cells, as they undergo necrosis. The described sensor was used to monitor the presence of the lipases released from three different cell lines, which were either exposed to highly cytotoxic model compounds (sodium azide and paracetamol) or subjected to freeze-thaw cycles to induce cell death by a non-chemical based inducer for apoptosis, such as temperature. Finally, the comparison of lipase activity detected by a state-of-the-art fluorescence assay to the LC based system resulted in the superiority of the LC system concerning incubation time and sensitivity.

  18. Chemiluminescence assay of lipase activity using a synthetic substrate as proenhancer for luminol chemiluminescence reaction.

    Science.gov (United States)

    Ichibangase, Tomoko; Ohba, Yoshihito; Kishikawa, Naoya; Nakashima, Kenichiro; Kuroda, Naotaka

    2004-01-01

    A novel chemiluminescence (CL) assay method for lipase (triacylglycerol lipase, E.C.3.1.1.3) activity was developed by using the lauric acid ester of 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (HDI) as a substrate. The method is based on the enhanced CL reaction of luminol-hydrogen peroxide-horseradish peroxidase (HRP) with HDI that is liberated from the substrate by enzymatic hydrolysis. To simplify the assay procedure, both the hydrolysis of the substrate and the enhanced CL reaction were performed in the same reaction mixture. Lipases from Candida cylindracea and porcine pancreas were successfully determined with the detection limits (blank signal + 3 SD) of 0.05 and 50.0 mU/tube, respectively. The method is simple and rapid, permitting the completion of single assay within 5 min. The reproducibilities obtained with replicate assays were relative standard deviations (RSDs) of 4.7% for within-day and 6.0% for between-day assays.

  19. A Novel Cold-Active Lipase from Candida albicans: Cloning, Expression and Characterization of the Recombinant Enzyme

    Directory of Open Access Journals (Sweden)

    Dong-Ming Lan

    2011-06-01

    Full Text Available A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM, which has double mutations that revert 154 and 293 to serine residues, showed good lipase activity, and was overexpressed and purified by (NH42SO4 precipitation and ion-exchange chromatography. The pure Lip5-DM was stable at low temperatures ranging from 15–35 °C and pH 5–9, with the optimal conditions being 15–25 °C and pH 5–6. The activation energy of recombinant lipase was 8.5 Kcal/mol between 5 and 25 °C, suggesting that Lip5-DM was a cold–active lipase. Its activity was found to increase in the presence of Zn2+, but it was strongly inhibited by Fe2+, Fe3+, Hg2+ and some surfactants. In addition, the Lip5-DM could not tolerate water-miscible organic solvents. Lip5-DM exhibited a preference for the short- and medium-chain length p-nitrophenyl (C4 and C8 acyl group esters rather than the long chain length p-nitrophenyl esters (C12, C16 and C18 acyl group with highest activity observed with the C8 derivatives. The recombinant enzyme displayed activity toward triacylglycerols, such as olive oil and safflower oil.

  20. A novel cold-active lipase from Candida albicans: cloning, expression and characterization of the recombinant enzyme.

    Science.gov (United States)

    Lan, Dong-Ming; Yang, Ning; Wang, Wen-Kai; Shen, Yan-Fei; Yang, Bo; Wang, Yong-Hua

    2011-01-01

    A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86-34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM, which has double mutations that revert 154 and 293 to serine residues, showed good lipase activity, and was overexpressed and purified by (NH(4))(2)SO(4) precipitation and ion-exchange chromatography. The pure Lip5-DM was stable at low temperatures ranging from 15-35 °C and pH 5-9, with the optimal conditions being 15-25 °C and pH 5-6. The activation energy of recombinant lipase was 8.5 Kcal/mol between 5 and 25 °C, suggesting that Lip5-DM was a cold-active lipase. Its activity was found to increase in the presence of Zn(2+), but it was strongly inhibited by Fe(2+), Fe(3+), Hg(2+) and some surfactants. In addition, the Lip5-DM could not tolerate water-miscible organic solvents. Lip5-DM exhibited a preference for the short-and medium-chain length p-nitrophenyl (C4 and C8 acyl group) esters rather than the long chain length p-nitrophenyl esters (C12, C16 and C18 acyl group) with highest activity observed with the C8 derivatives. The recombinant enzyme displayed activity toward triacylglycerols, such as olive oil and safflower oil.

  1. Synthesis of some new 1,2,4-triazole derivatives starting from 3-(4-chlorophenyl)-5-(4-methoxybenzyl)-4H-1,2,4-triazol with anti-lipase and anti-urease activities.

    Science.gov (United States)

    Bekircan, Olcay; Menteşe, Emre; Ulker, Serdar; Kucuk, Cagatay

    2014-06-01

    In the present study, starting compound 4 was prepared by deamination of compound 2 in the presence of hypophosphorous acid and sodium nitrite. Treatment of compound 4 with ethyl bromoacetate produced ethyl[3-(4-chlorophenyl)-5-(4-methoxybenzyl)-4H-1,2,4-triazol-4-yl]acetate (5), which was converted to the hydrazide derivative (6) by treatment with hydrazine hydrate. The reaction of compound 6 with aromatic aldehydes resulted in the formation of arylidene hydrazides (7). Treatment of 6 with CS2 in the presence of potassium hydroxide (KOH), followed by cyclization with hydrazine hydrate, afforded 4-amino-5-{[3-(4-chlorophenyl)-5-(4-methoxybenzyl)-4H-1,2,4-triazol-4-yl]methyl}-2,4-dihydro-3H-1,2,4-triazole-3-thione (9). The condensation of 9 with appropriate aldehydes gave Schiff bases (10), which were converted into Mannich bases (11) in the presence of formaldehyde. All the synthesized compounds were screened for their anti-lipase and anti-urease activities. Compounds 7b, 7d, 11b, 11c, and 11d showed moderate-to-good lipase inhibitory effects compared to orlistat. Compounds 7b and 7d exhibited better anti-lipase activity. Furthermore, among the compounds tested, 11a and 11d were found to show high inhibitory effect against urease with IC50 values of 12.39 ± 0.35 and 16.12 ± 1.06 µg/mL, respectively. Compound 11c showed moderate inhibitory activity. The Mannich base containing compound 11 may be a source of good leads for the synthesis of lipase and urease dual inhibitors.

  2. 4-Phenylcoumarins from Mesua elegans with acetylcholinesterase inhibitory activity.

    Science.gov (United States)

    Awang, Khalijah; Chan, Gomathi; Litaudon, Marc; Ismail, Nor Hadiani; Martin, Marie-Thérèse; Gueritte, Françoise

    2010-11-15

    A significant acetylcholinesterase (AChE) inhibitory activity was observed for the hexane extract from the bark of Mesua elegans (Clusiaceae). Thus, the hexane extract was subjected to chemical investigation, which led to the isolation of nine 4-phenylcoumarins, in which three are new; mesuagenin A (1), mesuagenin C (3), mesuagenin D (4) and one new natural product; mesuagenin B (2). The structures of the isolated compounds were characterized by spectroscopic data interpretation, especially 1D and 2D NMR. Four compounds showed significant AChE inhibitory activity, with mesuagenin B (2) being the most potent (IC(50)=0.7μM). Copyright © 2010. Published by Elsevier Ltd.

  3. Inhibitory effect of burdock leaves on elastase and tyrosinase activity

    Science.gov (United States)

    Horng, Chi-Ting; Wu, Hsing-Chen; Chiang, Ni-Na; Lee, Chiu-Fang; Huang, Yu-Syuan; Wang, Hui-Yun; Yang, Jai-Sing; Chen, Fu-An

    2017-01-01

    Burdock (Arctium lappa L.) leaves generate a considerable amount of waste following burdock root harvest in Taiwan. To increase the use of burdock leaves, the present study investigated the optimal methods for producing burdock leaf extract (BLE) with high antioxidant polyphenolic content, including drying methods and solvent extraction concentration. In addition, the elastase and tyrosinase inhibitory activity of BLE was examined. Burdock leaves were dried by four methods: Shadow drying, oven drying, sun drying and freeze-drying. The extract solution was then subjected to total polyphenol content analysis and the method that produced BLE with the highest amount of total antioxidant components was taken forward for further analysis. The 1,1-diphenyl-2-pycrylhydrazyl scavenging, antielastase and antityrosinase activity of the BLE were measured to enable the evaluation of the antioxidant and skin aging-associated enzyme inhibitory activities of BLE. The results indicated that the total polyphenolic content following extraction with ethanol (EtOH) was highest using the freeze-drying method, followed by the oven drying, shadow drying and sun drying methods. BLE yielded a higher polyphenol content and stronger antioxidant activity as the ratio of the aqueous content of the extraction solvent used increased. BLE possesses marked tyrosinase and elastase inhibitory activities, with its antielastase activity notably stronger compared with its antityrosinase activity. These results indicate that the concentration of the extraction solvent was associated with the antioxidant and skin aging-associated enzyme inhibitory activity of BLE. The reactive oxygen species scavenging theory of skin aging may explain the tyrosinase and elastase inhibitory activity of BLE. In conclusion, the optimal method for obtaining BLE with a high antioxidant polyphenolic content was freeze-drying followed by 30–50% EtOH extraction. In addition, the antielastase and antityrosinase activities of the

  4. Decorrelation of Neural-Network Activity by Inhibitory Feedback

    Science.gov (United States)

    Einevoll, Gaute T.; Diesmann, Markus

    2012-01-01

    Correlations in spike-train ensembles can seriously impair the encoding of information by their spatio-temporal structure. An inevitable source of correlation in finite neural networks is common presynaptic input to pairs of neurons. Recent studies demonstrate that spike correlations in recurrent neural networks are considerably smaller than expected based on the amount of shared presynaptic input. Here, we explain this observation by means of a linear network model and simulations of networks of leaky integrate-and-fire neurons. We show that inhibitory feedback efficiently suppresses pairwise correlations and, hence, population-rate fluctuations, thereby assigning inhibitory neurons the new role of active decorrelation. We quantify this decorrelation by comparing the responses of the intact recurrent network (feedback system) and systems where the statistics of the feedback channel is perturbed (feedforward system). Manipulations of the feedback statistics can lead to a significant increase in the power and coherence of the population response. In particular, neglecting correlations within the ensemble of feedback channels or between the external stimulus and the feedback amplifies population-rate fluctuations by orders of magnitude. The fluctuation suppression in homogeneous inhibitory networks is explained by a negative feedback loop in the one-dimensional dynamics of the compound activity. Similarly, a change of coordinates exposes an effective negative feedback loop in the compound dynamics of stable excitatory-inhibitory networks. The suppression of input correlations in finite networks is explained by the population averaged correlations in the linear network model: In purely inhibitory networks, shared-input correlations are canceled by negative spike-train correlations. In excitatory-inhibitory networks, spike-train correlations are typically positive. Here, the suppression of input correlations is not a result of the mere existence of correlations between

  5. BACE1 and cholinesterase inhibitory activities of Nelumbo nucifera embryos.

    Science.gov (United States)

    Jung, Hyun Ah; Karki, Subash; Kim, Ji Hye; Choi, Jae Sue

    2015-06-01

    The aim of the present study was to evaluate the comparative anti-Alzheimer's disease (AD) activities of different parts of Nelumbo nucifera (leaves, de-embryo seeds, embryos, rhizomes, and stamens) in order to determine the selectivity and efficient use of its individual components. Anti-AD activities of different parts of N. nucifera were evaluated via inhibitory activities on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) along with scavenging activity on peroxynitrite (ONOO(-)). Among the evaluated parts of N. nucifera, the embryo extract exhibited significant inhibitory potential against BACE1 and BChE as well as scavenging activity against ONOO(-). Thus, the embryo extract was selected for detailed investigation on anti-AD activity using BACE1- and ChEs-inhibitory assays. Among the different solvent-soluble fractions, the dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butanol (n-BuOH) fractions showed promising ChEs and BACE1 inhibitory activities. Repeated column chromatography of the CH2Cl2, EtOAc and n-BuOH fractions yielded compounds 1-5, which were neferine (1), liensinine (2), vitexin (3), quercetin 3-O-glucoside (4) and northalifoline (5). Compound 2 exhibited potent inhibitory activities on BACE1, AChE, and BChE with respective IC50 values of 6.37 ± 0.13, 0.34 ± 0.02, and 9.96 ± 0.47 µM. Likewise, compound 1 showed potent inhibitory activities on BACE1, AChE, and BChE with IC50 values of 28.51 ± 4.04, 14.19 ± 1.46, and 37.18 ± 0.59 µM, respectively; the IC50 values of 3 were 19.25 ± 3.03, 16.62 ± 1.43, and 11.53 ± 2.21 µM, respectively. In conclusion, we identified potent ChEs- and BACE1-inhibitory activities of N. nucifera as well as its isolated constituents, which may be further explored to develop therapeutic and preventive agents for AD and oxidative stress related diseases.

  6. A recombinant wheat serpin with inhibitory activity

    DEFF Research Database (Denmark)

    Rasmussen, Søren K; Dahl, Søren Weis; Nørgård, Anette

    1996-01-01

    A full-length clone encoding the wheat (Triticum aestivum L.) serpin WSZ1 was isolated from a cDNA library based on mRNA from immature grain. The 398 amino acid sequence deduced from the cDNA was corroborated by sequencing CNBr peptides of WSZ1 purified from resting grain. WSZ1 belongs...... to the subfamily of protein Z-type serpins and the amino acid sequence is 70%, identical with the barley serpins BSZ4 and BSZx and 27-33% identical with human serpins such as alpha(1)-proteinase inhibitor, antithrombin III, and plasminogen activator inhibitor. The cDNA was subcloned in the pET3d expression vector......, equipped with a histidine affinity tag at the N-terminus and expressed in Escherichia coli BL(21) DE3 pLysS. Recombinant WSZ1 from the soluble fraction was partially purified on Ni-NTA agarose and MonoQ columns and shown to form SDS-stable complexes with sc-chymotrypsin. Southern blots and amino acid...

  7. Expression and chaperone-assisted refolding of a new cold-active lipase from Psychrobacter cryohalolentis K5(T).

    Science.gov (United States)

    Novototskaya-Vlasova, Ksenia; Petrovskaya, Lada; Kryukova, Elena; Rivkina, Elizaveta; Dolgikh, Dmitry; Kirpichnikov, Mikhail

    2013-09-01

    We describe cloning and expression of genes coding for lipase Lip2Pc and lipase-specific foldase LifPc from a psychrotrophic microorganism Psychrobacter cryohalolentis K5(T) isolated from a Siberian cryopeg (the lense of overcooled brine within permafrost). Upon expression in Escherichiacoli Lip2Pc accumulated in inclusion bodies while chaperone was synthesized in a soluble form. An efficient protocol for solubilization and subsequent refolding of the recombinant lipase in the presence of the truncated chaperone was developed. Using this procedure Lip2Pc with specific activity of 6900U/mg was obtained. Contrary to published data on other lipase-chaperone complexes, refolded Lip2Pc was mostly recovered from the complex with chaperone by metal-affinity chromatography. Recombinant Lip2Pc displayed maximum lipolytic activity at 25°C and pH 8.0 with p-nitrophenyl palmitate (C16) as a substrate. Activity assays conducted at different temperatures revealed that the recombinant Lip2Pc is a cold-adapted lipase with ability to utilize substrates with long (C10-C16) hydrocarbon chains in the temperature range from +5 to +65°C. It demonstrated relatively high stability at temperatures above 60°C and in the presence of various metal ions or organic solvents (ethanol, methanol, etc.). Non-ionic detergents, such as Triton X-100 and Tween 20 decreased Lip2Pc activity and SDS completely inhibited it.

  8. Combination of site-directed mutagenesis and yeast surface display enhances Rhizomucor miehei lipase esterification activity in organic solvent.

    Science.gov (United States)

    Han, Shuang-yan; Zhang, Jun-hui; Han, Zhen-lin; Zheng, Sui-ping; Lin, Ying

    2011-12-01

    To increase the activity of Rhizomucor miehei lipase (RML) in organic solvent, multiple sequence alignments and rational site-directed mutagenesis were used to create RML variants. The obtained proteins were surface-displayed on Pichia pastoris by fusion to Flo1p as an anchor protein. The synthetic activity of four variants showed from 1.1- to 5-fold the activity of native lipase in an esterification reaction in heptane with alcohol and caproic acid as substrates. The increase in esterification activity may be attributed to the four mutations changing the flexibility of RML or facilitating the reaction. In conclusion, this method demonstrated that multiple sequence alignments and rational site-directed mutagenesis combined with yeast display technology is a faster and more effective means of obtaining high-efficiency esterification lipase variants compared with previous similar methods.

  9. Human adipose triglyceride lipase (PNPLA2) is not regulated by obesity and exhibits low in vitro triglyceride hydrolase activity.

    Science.gov (United States)

    Mairal, A; Langin, D; Arner, P; Hoffstedt, J

    2006-07-01

    The recent identification of murine adipose triglyceride lipase (ATGL, now known as patatin-like phospholipase domain containing 2 [PNPLA2]), gene product of Pnpla2, has questioned the unique role of hormone sensitive lipase (HSL, now known as LIPE), gene product of Lipe, in fat cell lipolysis. Here, we investigated human ATGL and HSL adipose tissue gene expression and in vitro lipase activity. Levels of mRNA in adipose tissue from healthy obese and non-obese subjects were measured and lipase activity and adipocyte lipolytic capacity determined. HSL and ATGL cDNAs were transfected into Cos-7 cells and the relative tri- and diglyceride hydrolase activities were measured. Obesity was associated with a decreased subcutaneous and increased omental adipose tissue level of HSL mRNA. Subcutaneous HSL mRNA content was normalised upon weight reduction. In contrast, ATGL mRNA levels were unaffected by obesity and weight reduction. A high adipose tissue lipase activity was associated with increased maximal lipolysis and increased HSL, but not with ATGL mRNA levels. The in vitro triglyceride hydrolase activity of HSL was markedly higher than that of ATGL and contrary to HSL, ATGL was devoid of diglyceride hydrolase activity. The use of a selective HSL-inhibitor resulted in complete inhibition of HSL-mediated tri- and diglyceride hydrolase activity. The pH profile of human white adipose tissue triolein hydrolase activity was identical to that of HSL but differed from the ATGL profile. HSL, but not ATGL gene expression shows a regulation according to obesity status and is associated with increased adipose tissue lipase activity. Moreover, HSL has a higher capacity than ATGL to hydrolyse triglycerides in vitro.

  10. MICROWAVE ACTIVATION OF IMMOBILIZED LIPASE FOR TRANSESTERIFICATION OF VEGETABLE OILS

    Directory of Open Access Journals (Sweden)

    Monna Lisa B. Queiroz

    2015-03-01

    Full Text Available This work investigated the effect of microwave irradiation (MW on the ethanolysis rate of soybean and sunflower oils catalyzed by supported Novozyme 435 (Candida antarctica. The effects of tert-butanol, water addition and oil:ethanol molar ratio on transesterification were evaluated under conventional heating (CH, and under optimum reaction conditions (with no added water in the system, 10% tert-butanol and 3:1 ethanol-to-oil molar ratio. The reactions were monitored up to 24 h to determine the conditions of initial reaction velocity. The investigated variables under MW (50 W were: reaction time (5.0-180 min and mode of reactor operation (fixed power, dynamic and cycles in the absence and presence of tert-butanol (10% (w/w. The measured response was the reaction conversion in ethyl esters, which was linked to the enzyme catalytic activity. The results indicated that the use of microwave improved the activity at fixed power mode. A positive effect of the association of tert-butanol and MW irradiation on the catalytic activity was observed. The reaction rate improved in the order of approximately 1.5 fold compared to that under CH with soybean oil. Using soybean oil, the enzymatic transesterification under MW for conversion to FAEE (fatty acid ethyl esters reached >99% in 3h, while with the use of CH the conversions were about 57% under similar conditions.

  11. Glycolipid Biosurfactants Activate, Dimerize, and Stabilize Thermomyces lanuginosus Lipase in a pH-Dependent Fashion.

    Science.gov (United States)

    Madsen, Jens Kvist; Kaspersen, Jørn Døvling; Andersen, Camilla Bertel; Nedergaard Pedersen, Jannik; Andersen, Kell Kleiner; Pedersen, Jan Skov; Otzen, Daniel E

    2017-08-15

    We present a study of the interactions between the lipase from Thermomyces lanuginosus (TlL) and the two microbially produced biosurfactants (BSs), rhamnolipid (RL) and sophorolipid (SL). Both RL and SL are glycolipids; however, RL is anionic, while SL is a mixture of anionic and non-ionic species. We investigate the interactions of RL and SL with TlL at pH 6 and 8 and observe different effects at the two pH values. At pH 8, neither RL nor SL had any major effect on TlL stability or activity. At pH 6, in contrast, both surfactants increase TlL's thermal stability and fluorescence and activity measurements indicate interfacial activation of TlL, resulting in 3- and 6-fold improved activity in SL and RL, respectively. Nevertheless, isothermal titration calorimetry reveals binding of only a few BS molecules per lipase. Size-exclusion chromatography and small-angle X-ray scattering suggest formation of TlL dimers with binding of small amounts of either RL or SL at the dimeric interface, forming an elongated complex. We conclude that RL and SL are compatible with TlL and constitute promising green alternatives to traditional surfactants.

  12. Proteinuria and lipoprotein lipase activity in Miniature Schnauzer dogs with and without hypertriglyceridemia.

    Science.gov (United States)

    Furrow, E; Jaeger, J Q; Parker, V J; Hinchcliff, K W; Johnson, S E; Murdoch, S J; de Boer, I H; Sherding, R G; Brunzell, J D

    2016-06-01

    Spontaneous hyperlipidemia in rats causes glomerular disease. Idiopathic hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, but its relationship with proteinuria is unknown. Decreased activity of major lipid metabolism enzymes, lipoprotein lipase (LPL) and hepatic lipase (HL), may play a role in the cyclic relationship between hyperlipidemia and proteinuria. These enzymes have also not been previously investigated in Miniature Schnauzers. The aims of this study were to determine the relationship between HTG and proteinuria in Miniature Schnauzers and to measure LPL and HL activities in a subset of dogs. Fifty-seven Miniature Schnauzers were recruited (34 with and 23 without HTG). Fasting serum triglyceride concentrations and urine protein-to-creatinine ratios (UPC) were measured in all dogs, and LPL and HL activities were determined in 17 dogs (8 with and 9 without HTG). There was a strong positive correlation between triglyceride concentration and UPC (r = 0.77-0.83, P Proteinuria (UPC ≥ 0.5) was present in 60% of dogs with HTG and absent from all dogs without HTG (P Proteinuria occurs with HTG in Miniature Schnauzers and could be due to lipid-induced glomerular injury. Reduced LPL activity may contribute to the severity of HTG, but further assay validation is required. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Uml2 is a novel CalB-type lipase of Ustilago maydis with phospholipase A activity.

    Science.gov (United States)

    Buerth, Christoph; Kovacic, Filip; Stock, Janpeter; Terfrüchte, Marius; Wilhelm, Susanne; Jaeger, Karl-Erich; Feldbrügge, Michael; Schipper, Kerstin; Ernst, Joachim F; Tielker, Denis

    2014-06-01

    CalB of Pseudozyma aphidis (formerly named Candida antarctica) is one of the most widely applied enzymes in industrial biocatalysis. Here, we describe a protein with 66 % sequence identity to CalB, designated Ustilago maydis lipase 2 (Uml2), which was identified as the product of gene um01422 of the corn smut fungus U. maydis. Sequence analysis of Uml2 revealed the presence of a typical lipase catalytic triad, Ser-His-Asp with Ser125 located in a Thr-Xaa-Ser-Xaa-Gly pentapeptide. Deletion of the uml2 gene in U. maydis diminished the ability of cells to hydrolyse fatty acids from tributyrin or Tween 20/80 substrates, thus demonstrating that Uml2 functions as a lipase that may contribute to nutrition of this fungal pathogen. Uml2 was heterologously produced in Pichia pastoris and recombinant N-glycosylated Uml2 protein was purified from the culture medium. Purified Uml2 released short- and long-chain fatty acids from p-nitrophenyl esters and Tween 20/80 substrates. Furthermore, phosphatidylcholine substrates containing long-chain saturated or unsaturated fatty acids were effectively hydrolysed. Both esterase and phospholipase A activity of Uml2 depended on the Ser125 catalytic residue. These results indicate that Uml2, in contrast to CalB, exhibits not only esterase and lipase activity but also phospholipase A activity. Thus, by genome mining, we identified a novel CalB-like lipase with different substrate specificities.

  14. Synthesis, topoisomerase I inhibitory and cytotoxic activities of chromone derivatives.

    Science.gov (United States)

    Maicheen, Chirattikan; Jittikoon, Jiraphun; Vajragupta, Opa; Ungwitayatorn, Jiraporn

    2013-05-01

    A series of chromone derivatives were designed as potential topoisomerase I (Top I) inhibitors based on the docking simulation study. Sixteen synthesized compounds were evaluated for Top I inhibitory activity and some compounds were further tested for in vitro cytotoxic activity. The most potent inhibitor, chromone 11b showed greater inhibitory activity (IC50 = 1.46 μM) than the known Top I inhibitors, i.e., camptothecin, fisetin and morin, but inactive against breast cancer cell (MCF-7), oral cavity cancer cell (KB) and small cell lung cancer (NCI-H187). Chromone 11c, another potent inhibitor (IC50 = 6.16 μM), exhibited cytotoxic activity against KB (IC50 = 73.32 μM) and NCI-H187 (IC50 = 36.79 μM).

  15. Serum lipase activity and concentration during intravenous infusions of GLP-1 and PYY3-36 and after ad libitum meal ingestion in overweight men

    DEFF Research Database (Denmark)

    Schmidt, Julie Berg; Sjödin, Anders Mikael; Stevner, Lene Susanne;

    2016-01-01

    To examine the effect on serum lipase activity and protein concentration of intravenous infusions of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY3-36) and of an ad libitum meal in healthy overweight men. Twenty-five healthy, male subjects participated in this randomized, double...... the infusion and after intake of an ad libitum meal for measurement of serum lipase. Serum lipase levels measured by enzyme-linked immunosorbent assay (ELISA) following mono-infusions of GLP-1 and PYY3-36 were comparable to serum lipase levels following placebo (P = 0.054 and P = 0.873, respectively...

  16. Study of nickel and chrome influnce on lipid content and lipase activity in the germinating maize grains

    Directory of Open Access Journals (Sweden)

    I. O. Filonik

    2009-07-01

    Full Text Available The influence of heavy metals – nickel and chromium – on the indices of lipid metabolism in seeds of the maize hybrid Blith 160 MV at the germination was studied. The reduction of the total lipid content and phospholipids, but increase of lipases activity, sterols and free fatty acids in the germinating grains under the toxicant action were revealed. Changes in the lipids content and lipases activity in the germinating maize seeds may be used as markers of the heavy metals influence on plants.

  17. Pancreatic lipase activity in overnight effluent predicts high transport status in peritoneal dialysis patients.

    Science.gov (United States)

    Idei, Mayumi; Tabe, Yoko; Hamada, Chieko; Miyake, Kazunori; Takemura, Hiroyuki; Io, Hiroaki; Wakita, Mitsuru; Horii, Takashi; Tomino, Yasuhiko; Ohsaka, Akimichi; Miida, Takashi

    2016-11-01

    Long-term peritoneal dialysis (PD) causes peritoneal morphological and functional changes, resulting in high transport status featuring increased peritoneal permeability. High transport status is diagnosed by peritoneal equilibration test (PET), a reliable but time-consuming method. We identifed a reliable biomarker in peritoneal effluent to predict high transport status in PD patients. We collected peritoneal effluent and serum from 33 PD patients and measured common laboratory test parameters. High transport status was determined by PET if the dialysate/plasma ratio of creatinine at 4h dwell (D/P Cr 4h) was ≥0.81. There were significant correlations between D/P Cr 4h and some laboratory parameters in overnight effluent (pancreatic lipase activity, r=0.65, povernight effluent was identified as an independent predictor of high transport status even after adjusting for age, PD duration, and glomerular filtration rate [OR=1.43 (95% CI: 1.11-1.83), p=0.005]. The pancreatic lipase activity in overnight effluent is an independent predictor of high transport status in PD patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Protease and lipase activities of fungal and bacterial strains derived from an artisanal raw ewe's milk cheese

    NARCIS (Netherlands)

    Ozturkoglu Budak, Sebnem; Wiebenga, Ad; Bron, Peter A; de Vries, Ronald P

    2016-01-01

    We previously identified the microbiota present during cheese ripening and observed high protease and lipase activity in Divle Cave cheese. To determine the contribution of individual isolates to enzyme activities, we investigated a range of species representing this microbiota for their proteolytic

  19. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle

    DEFF Research Database (Denmark)

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel

    2010-01-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose...... tissue suggests that testosterone regulates HSL activity. To test whether this is also true in the heart, we measured HSL activity in the left ventricle of sedentary male rats that had been treated with testosterone supplementation or orchidectomy with or without testosterone substitution. Left ventricle...... HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid...

  20. Expression of human hormone-sensitive lipase in white adipose tissue of transgenic mice increases lipase activity but does not enhance in vitro lipolysis.

    Science.gov (United States)

    Lucas, Stéphanie; Tavernier, Geneviève; Tiraby, Claire; Mairal, Aline; Langin, Dominique

    2003-01-01

    Hormone-sensitive lipase (HSL) catalyzes the hydrolysis of acylglycerols and cholesteryl esters (CEs). The enzyme is highly expressed in adipose tissues (ATs), where it is thought to play an important role in fat mobilization. The purpose of the present work was to study the effect of a physiological increase of HSL expression in vivo. Transgenic mice were produced with a 21 kb human genomic fragment encompassing the exons encoding the adipocyte form of HSL. hHSL mRNA was expressed at 3-fold higher levels than murine HSL mRNA in white adipocytes. Transgene expression was also observed in brown adipose tissue (BAT) and skeletal muscle. The human protein was detected in ATs of transgenic (Tg) mice. The hydrolytic activities against triacylglycerol (TG), diacylglycerol (DG) analog, and CE were increased in transgenic mouse AT. However, cAMP-inducible adipocyte lipolysis was lower in transgenic animals. In the B6CBA genetic background, transgenic mice up to 14 weeks of age showed lower body weight and fat mass. The phenotype was not observed in older animals and in mice fed a high-fat diet (HFD). In the OF1 genetic background, there was no difference in fat mass of mice fed ad libitum. However, transgenic mice became leaner than their wild-type (WT) littermates after a 4 day calorie restriction. The data show that overexpression of HSL, despite increased lipase activity, does not lead to enhanced lipolysis.

  1. Urease inhibitory activities of beta-boswellic acid derivatives

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    Reza Hajiaghaee

    2013-01-01

    Full Text Available Background and the purpose of the study: Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative.Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-beta-boswellic acid; 2, 3-O-acetyl-11-hydroxy-beta-boswellic acid; 3. 3-O- acetyl-11-keto-beta-boswellic acid and 4, 11-keto-beta-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme.Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 +/- 0.03 muM, compared with thiourea as a standard inhibitor (IC50 = 21.1 +/- 0.3 muM.Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage.

  2. Urease inhibitory activities of β-boswellic acid derivatives

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    Amanlou Massoud

    2013-01-01

    Full Text Available Abstract Background and the purpose of the study Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative. Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-β-boswellic acid; 2, 3-O-acetyl-11-hydroxy-β-boswellic acid; 3. 3-O- acetyl-11-keto-β-boswellic acid and 4, 11-keto-β-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme. Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 ± 0.03 μM, compared with thiourea as a standard inhibitor (IC50 = 21.1 ± 0.3 μM. Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage.

  3. Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.

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    Paula Monteiro Souza

    Full Text Available The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05 tyrosinase inhibitory activity exhibiting the IC₅₀ value of 11.88 µg/mL, compared to kojic acid (IC₅₀ value of 13.14 µg/mL. Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC₅₀ value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations.

  4. Prediction of PKCθ Inhibitory Activity Using the Random Forest Algorithm

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    Shuwei Zhang

    2010-09-01

    Full Text Available This work is devoted to the prediction of a series of 208 structurally diverse PKCθ inhibitors using the Random Forest (RF based on the Mold2 molecular descriptors. The RF model was established and identified as a robust predictor of the experimental pIC50 values, producing good external R2pred of 0.72, a standard error of prediction (SEP of 0.45, for an external prediction set of 51 inhibitors which were not used in the development of QSAR models. By using the RF built-in measure of the relative importance of the descriptors, an important predictor—the number of group donor atoms for H-bonds (with N and O―has been identified to play a crucial role in PKCθ inhibitory activity. We hope that the developed RF model will be helpful in the screening and prediction of novel unknown PKCθ inhibitory activity.

  5. Tyrosinase inhibitory components from Aloe vera and their antiviral activity.

    Science.gov (United States)

    Kim, Jang Hoon; Yoon, Ju-Yeon; Yang, Seo Young; Choi, Seung-Kook; Kwon, Sun Jung; Cho, In Sook; Jeong, Min Hee; Ho Kim, Young; Choi, Gug Seoun

    2017-12-01

    A new compound, 9-dihydroxyl-2'-O-(Z)-cinnamoyl-7-methoxy-aloesin (1), and eight known compounds (2-9) were isolated from Aloe vera. Their structures were elucidated using 1D/2D nuclear magnetic resonance and mass spectra. Compound 9 exhibited reversible competitive inhibitory activity against the enzyme tyrosinase, with an IC50 value of 9.8 ± 0.9 µM. A molecular simulation revealed that compound 9 interacts via hydrogen bonding with residues His244, Thr261, and Val283 of tyrosinase. Additionally, compounds 3 and 7 were shown by half-leaf assays to exhibit inhibitory activity towards Pepper mild mottle virus.

  6. Fatty acid-releasing activities in Sinorhizobium meliloti include unusual diacylglycerol lipase.

    Science.gov (United States)

    Sahonero-Canavesi, Diana X; Sohlenkamp, Christian; Sandoval-Calderón, Mario; Lamsa, Anne; Pogliano, Kit; López-Lara, Isabel M; Geiger, Otto

    2015-09-01

    Phospholipids are well known for their membrane-forming properties and thereby delimit any cell from the exterior world. In addition, membrane phospholipids can act as precursors for signals and other biomolecules during their turnover. Little is known about phospholipid signalling, turnover and remodelling in bacteria. Recently, we showed that a FadD-deficient mutant of Sinorhizobium meliloti, unable to convert free fatty acids to their coenzyme A derivatives, accumulates free fatty acids during the stationary phase of growth. Enzymatic activities responsible for the generation of these free fatty acids were unknown in rhizobia. Searching the genome of S. meliloti, we identified a potential lysophospholipase (SMc04041) and two predicted patatin-like phospholipases A (SMc00930, SMc01003). Although SMc00930 as well as SMc01003 contribute to the release of free fatty acids in S. meliloti, neither one can use phospholipids as substrates. Here we show that SMc01003 converts diacylglycerol to monoacylglycerol and a fatty acid, and that monoacylglycerol can be further degraded by SMc01003 to another fatty acid and glycerol. A SMc01003-deficient mutant of S. meliloti transiently accumulates diacylglycerol, suggesting that SMc01003 also acts as diacylglycerol lipase (DglA) in its native background. Expression of the DglA lipase in Escherichia coli causes lysis of cells in stationary phase of growth.

  7. Death and rebirth of neural activity in sparse inhibitory networks

    OpenAIRE

    Angulo-Garcia, David; Luccioli, Stefano; Olmi, Simona; Torcini, Alessandro

    2016-01-01

    In this paper, we clarify the mechanisms underlying a general phenomenon present in pulse-coupled heterogeneous inhibitory networks: inhibition can induce not only suppression of the neural activity, as expected, but it can also promote neural reactivation. In particular, for globally coupled systems, the number of firing neurons monotonically reduces upon increasing the strength of inhibition (neurons' death). However, the random pruning of the connections is able to reverse the action of in...

  8. Urease inhibitory activities of beta-boswellic acid derivatives

    OpenAIRE

    Reza Hajiaghaee; Behnam Yousefi; Zinat Bahrampour Omrany; Farzaneh Nabati; Sahand Golestanian; Roya Bazl; Sanaz Golbabaei; "Shamsali Rezazadeh; Massoud Amanlou

    2013-01-01

    Background and the purpose of the study: Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative.Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-beta-boswellic acid; 2, 3-O-acetyl-11-hydrox...

  9. Urease inhibitory activities of β-boswellic acid derivatives

    OpenAIRE

    Amanlou Massoud; Rezazadeh Shamsali; Hajiaghaee Reza; Nabati Farzaneh; Yousefi Behnam; Omrany Zinat Bahrampour; Golestanian Sahand; Bazl Roya; Golbabaei Sanaz

    2013-01-01

    Abstract Background and the purpose of the study Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative. Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-β-boswellic acid; 2, 3-O-acetyl-11-...

  10. Nanoclays for Lipase Immobilization: Biocatalyst Characterization and Activity in Polyester Synthesis

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    Hale Öztürk

    2016-12-01

    Full Text Available The immobilization of Candida antarctica lipase B (CALB was performed by physical adsorption on both neat and organo-modified forms of sepiolite and montmorillonite. The influence of different parameters, e.g., solvent, enzyme loading, cross-linking, and type of clay support, on immobilization efficiency and catalyst hydrolytic activity has been investigated. The highest hydrolytic activities were obtained for CALB immobilized on organo-modified clay minerals, highlighting the beneficial effect of organo-modification. The esterification activity of these CALB/organoclay catalysts was also tested in the ring-opening polymerization of ε-caprolactone. The polymerization kinetics observed for clay-immobilized catalysts confirmed that CALB adsorbed on organo-modified montmorillonite (CALB/MMTMOD was the highest-performing catalytic system.

  11. Monitoring Lipase/Esterase Activity by Stopped Flow in a Sequential Injection Analysis System Using p-Nitrophenyl Butyrate

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    Jorge Pliego

    2015-01-01

    Full Text Available Lipases and esterases are biocatalysts used at the laboratory and industrial level. To obtain the maximum yield in a bioprocess, it is important to measure key variables, such as enzymatic activity. The conventional method for monitoring hydrolytic activity is to take out a sample from the bioreactor to be analyzed off-line at the laboratory. The disadvantage of this approach is the long time required to recover the information from the process, hindering the possibility to develop control systems. New strategies to monitor lipase/esterase activity are necessary. In this context and in the first approach, we proposed a lab-made sequential injection analysis system to analyze off-line samples from shake flasks. Lipase/esterase activity was determined using p-nitrophenyl butyrate as the substrate. The sequential injection analysis allowed us to measure the hydrolytic activity from a sample without dilution in a linear range from 0.05–1.60 U/mL, with the capability to reach sample dilutions up to 1000 times, a sampling frequency of five samples/h, with a kinetic reaction of 5 min and a relative standard deviation of 8.75%. The results are promising to monitor lipase/esterase activity in real time, in which optimization and control strategies can be designed.

  12. A new TLC bioautographic assay for qualitative and quantitative estimation of lipase inhibitors.

    Science.gov (United States)

    Tang, Jihe; Zhou, Jinge; Tang, Qingjiu; Wu, Tao; Cheng, Zhihong

    2016-01-01

    Lipase inhibitory assays based on TLC bioautography have made recent progress; however, an assay with greater substrate specificity and quantitative capabilities would advance the efficacy of this particular bioassay. To address these limitations, a new TLC bioautographic assay for detecting lipase inhibitors was developed and validated in this study. The new TLC bioautographic assay was based on reaction of lipase with β-naphthyl myristate and the subsequent formation of the purple dye between β-naphthol and Fast Blue B salt (FBB). The relative lipase inhibitory capacity (RLIC) was determined by a TLC densitometry with fluorescence detection, expressed as orlistat equivalents in millimoles on a per sample weight basis. Six pure compounds and three natural extracts were evaluated for their potential lipase inhibitory activities by this TLC bioautographic assay. The β-naphthyl myristate as the substrate improved the detection sensitivity and specificity significantly. The limit of detection (LOD) of this assay was 0.01 ng for orlistat, the current treatment for obesity. This assay has acceptable accuracy (92.07-105.39%), intra-day and inter-day precisions [relative standard deviation (RSD), 2.64-4.40%], as well as intra-plate and inter-plate precisions (RSD, 1.8-4.9%). The developed method is rapid, simple, stable, and specific for screening and estimation of the potential lipase inhibitors. Copyright © 2015 John Wiley & Sons, Ltd.

  13. Enhanced activity of Rhizomucor miehei lipase by deglycosylation of its propeptide in Pichia pastoris.

    Science.gov (United States)

    Liu, Yue; Xie, Wenping; Yu, Hongwei

    2014-02-01

    Many studies have demonstrated that the properties of enzymes expressed in eukaryotes can be affected by the position and extent of glycosylation on enzyme. In this study, two potential glycosylation sites (the 8th and the 58th asparagine) were identified and the effect of propeptide glycosylation on Rhizomucor miehei lipase (RML) expressed in Pichia pastoris was investigated. To better understand the effect of glycosylation on the activity of RML, three mutants (M1, generated by N8A; M2, generated by N58A; and M3, generated by N8A and N58A) were designed to generate deglycosylated enzymes. The results showed that deglycosylated RML exhibited a twofold higher activity compared to the wild type. However, it was also found that glycosylation on the propeptide was important for the removal of the propeptide by Kex2 protease and secretion of the enzyme. Thus, our study provided a further understanding into the role of glycosylation on enzyme function.

  14. Histamine release inhibitory activity of Piper nigrum leaf.

    Science.gov (United States)

    Hirata, Noriko; Naruto, Shunsuke; Inaba, Kazunori; Itoh, Kimihisa; Tokunaga, Masashi; Iinuma, Munekazu; Matsuda, Hideaki

    2008-10-01

    Oral administration of a methanolic extract of Piper nigrum leaf (PN-ext, 50, 200 and 500 mg/kg) showed a potent dose-dependent inhibition of dinitrofluorobenzene (DNFB)-induced cutaneous reaction at 1 h [immediate phase response (IPR)] after and 24 h [late phase response (LPR)] after DNFB challenge in mice which were passively sensitized with anti-dinitrophenyl (DNP) IgE antibody. Ear swelling inhibitory effect of PN-ext (50, 200 and 500 mg/kg, per os (p.o.)) on very late phase response (vLPR) in the model mice was significant but weaker than that on IPR. Oral administration of PN-ext (50, 200 and 500 mg/kg for 7 d) inhibited picryl chloride (PC)-induced ear swelling in PC sensitized mice. PN-ext exhibited in vitro inhibitory effect on compound 48/80-induced histamine release from rat peritoneal mast cells. Two lignans of PN-ext, (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2), were identified as major active principles having histamine release inhibitory activity.

  15. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase

    NARCIS (Netherlands)

    Schweiger, M.; Paar, M.; Eder, C.; Brandis, J.; Moser, E.; Gorkiewisz, G.; Grond, S.; Radner, F.P.W.; Cerk, I.; Cornaciu, I.; Oberer, M.; Kersten, A.H.; Zechner, R.; Zimmermann, M.B.; Lass, A.

    2012-01-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL)5, which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1 sw

  16. Effects of Fish Oil Diet and Age on the Fatty Acid Composition and the Endogenous Lipase Activity in Mouse Brain.

    Science.gov (United States)

    Suzuki, H; Jin, Z; Wada, O

    2000-01-01

    The influences of a fish oil diet and aging on the fatty acid composition in mouse brain, and the release of polyunsaturated fatty acids from brain membranes by endogenous lipase were studied. The changes in brain fatty acid composition with aging were determined in 5-weeks, 5-months and 19-months old mice fed on a commercial chow. Mice of different ages were also fed a fish oil or lard diet for 30 days, and the influence of the diets on brain fatty acid composition and endogenous lipase activity was analyzed. In aged mice fed on a commercial chow brain arachidonic acid and docosahexaenoic acid (%) decreased significantly, whereas blood arachidonic acid (%) increased and docosahexaenoic acid (%) did not change. The percentages of brain docosahexaenoic acid were significantly higher but those of arachidonic acid were lower in the fish oil diet group than in the lard diet group. However, there were no significant differences in the endogenous lipase activity between the different age or dietary groups. The release of arachidonic acid showed a tendency to decrease and docosahexaenoic acid to increase in mice fed on the fish oil diet. These results suggest that dietary lipids affect the percentages of arachidonic and docosahexaenoic acids which are released by the endogenous lipase in brain although the decreases in brain polyunsaturated fatty acid content with aging are not due to the enzyme activation, and dietary lipids do not influence the enzyme activity.

  17. Extracellular cold active lipase from the psychrotrophic Halomonas sp. BRI 8 isolated from the Antarctic sea water

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    Vipra Vijay Jadhav

    2013-12-01

    Full Text Available An extracellular cold active lipase-producing psychrotrophic bacterium (BRI 8 was isolated from the Antarctic sea water sample. The 16s rRNA sequence study revealed that the isolate belongs to the genus Halomonas (929 bp. The present paper reports optimization of fermentation conditions for production of lipase (EC 3.1.1.3 from Halomonas sp. BRI 8. Highest lipase production was observed in the medium containing olive oil and peptone. The optimum pH and temperature for enzyme catalysis were 7.0 and 10°C respectively. The enzyme was relatively more stable in acidic pH range and retained 50% activity when incubated at 30°C for 1 h. The enzyme was stable in various organic solvents and showed more than 100% activity in presence of isoamyl alcohol. Significant enzyme activity was also observed in the presence of metal ions and detergents. The molecular mass of partially purified lipase was found to be around 66 kD.

  18. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase

    NARCIS (Netherlands)

    Schweiger, M.; Paar, M.; Eder, C.; Brandis, J.; Moser, E.; Gorkiewisz, G.; Grond, S.; Radner, F.P.W.; Cerk, I.; Cornaciu, I.; Oberer, M.; Kersten, A.H.; Zechner, R.; Zimmermann, M.B.; Lass, A.

    2012-01-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL)5, which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1 sw

  19. Atorvastatin dose-dependently decreases hepatic lipase activity in type 2 diabetes: effect of sex and the LIPC promoter variant

    NARCIS (Netherlands)

    I.I.L. Berk-Planken (Ingrid); N. Hoogerbrugge (Nicoline); R.P. Stolk (Ronald); A.H. Bootsma (Aart); H. Jansen (Hans)

    2003-01-01

    textabstractOBJECTIVE: Hepatic lipase (HL) is involved in the metabolism of several lipoproteins and may contribute to the atherogenic lipid profile in type 2 diabetes. Little is known about the effect of cholesterol synthesis inhibitors on HL activity in relation to sex and the he

  20. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase

    NARCIS (Netherlands)

    Schweiger, M.; Paar, M.; Eder, C.; Brandis, J.; Moser, E.; Gorkiewisz, G.; Grond, S.; Radner, F.P.W.; Cerk, I.; Cornaciu, I.; Oberer, M.; Kersten, A.H.; Zechner, R.; Zimmermann, M.B.; Lass, A.

    2012-01-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL)5, which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1

  1. Antibacterial and biofilm inhibitory activities of bacteria associated with polychaetes

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    Chellamnadar Vaikundavasagom Sunjaiy Shankar

    2015-06-01

    Full Text Available Objective: To study the antibacterial and antibiofilm activities expressed by epibiotic bacteria associated with the polychaetes Platynereis dumerilii and Syllis sp. Methods: A total of 32 cultivable bacterial strains were isolated from the two polychaete species. The crude extracts were tested for antibacterial activity and biofilm inhibitory activity against pathogenic and biofilm-forming bacterial strains. Extracts of the strains which showed strong activity were analyzed by thin-layer chromatography (TLC and the bacterial strains were identified based on 16S rRNA gene sequencing. Results: Extracts of 13 bacterial strains showed inhibitory activity against pathogenic and biofilm-forming bacteria. The crude extracts also affected the synthesis of extracellular polymeric substances and cell surface hydrophobicity of the Alteromonas sp. isolated from marine biofilm. The adhesion of Alteromonas sp. on glass surface showed significant variation between surface-associated bacterial crude extract treatment and control groups. Among the 13 bacteria, two strains PA8 and PA19 were further analyzed for bioactive fractions. Thinlayer chromatography indicated the presence of a single active fraction in the crude extract of both the bacterial strains. The epibiotic bacterial strains P8 and P19 were identified as Exiguobacterium sp. and Actinobacterium sp. respectively based on 16S rRNA gene sequencing. Conclusions: The present study indicates that bacteria associated with marine invertebrates inhabiting the coastal waters could be used as a potential source for the isolation of bioactive metabolites.

  2. Antibacterial and bioiflm inhibitory activities of bacteria associated with polychaetes

    Institute of Scientific and Technical Information of China (English)

    Sathianeson Satheesh; Nadarajan Viju

    2015-01-01

    Objective:To study the antibacterial and antibiofilm activities expressed by epibiotic bacteria associated with the polychaetes Platynereis dumerilii and Syllis sp. Methods:A total of 32 cultivable bacterial strains were isolated from the two polychaete species. The crude extracts were tested for antibacterial activity and biofilm inhibitory activity against pathogenic and biofilm-forming bacterial strains. Extracts of the strains which showed strong activity were analyzed by thin-layer chromatography (TLC) and the bacterial strains were identified based on 16S rRNA gene sequencing. Results:Extracts of 13 bacterial strains showed inhibitory activity against pathogenic and biofilm-forming bacteria. The crude extracts also affected the synthesis of extracellular polymeric substances and cell surface hydrophobicity of the Alteromonas sp. isolated from marine biofilm. The adhesion of Alteromonas sp. on glass surface showed significant variation between surface-associated bacterial crude extract treatment and control groups. Among the 13 bacteria, two strains PA8 and PA19 were further analyzed for bioactive fractions. Thin-layer chromatography indicated the presence of a single active fraction in the crude extract of both the bacterial strains. The epibiotic bacterial strains P8 and P19 were identified as Exiguobacterium sp. and Actinobacterium sp. respectively based on 16S rRNA gene sequencing. Conclusions:The present study indicates that bacteria associated with marine invertebrates inhabiting the coastal waters could be used as a potential source for the isolation of bioactive metabolites.

  3. Oleate lipase activity in Gardnerella vaginalis and reconsideration of existing biotype schemes

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    Moncla Bernard J

    2009-04-01

    Full Text Available Abstract Background Gardnerella vaginalis is a facultative gram positive organism that requires subculture every 1–2 days to maintain viability. It has been linked with bacterial vaginosis (BV, a syndrome that has been associated with increased risk for preterm delivery, pelvic inflammatory disease and HIV acquisition. About 10% of the G. vaginalis isolates have been reported to produce sialidase, but there have not been any studies relating sialidase production and biotype. Sialidase activity is dramatically increased in the vaginal fluid of women with BV and bacterial sialidases have been shown to increase the infectivity of HIV in vitro. There are 8 different biotypes of G. vaginalis. Biotypes 1–4 produce lipase and were reported to be associated with BV and the association of these biotypes with BV is under dispute. Other studies have demonstrated that G. vaginalis biotype 1 can stimulate HIV-1 production. Because of the discrepancies in the literature we compared the methods used to biotype G. vaginalis and investigated the relationship of biotype and sialidase production. Results A new medium for maintenance of Gardnerella vaginalis which allows survival for longer than one week is described. Some isolates only grew well under anaerobic conditions. Sialidase producing isolates were observed in 5 of the 6 biotypes tested. Using 4-methylumbelliferyl-oleate to determine lipase activity, instead of egg yolk agar, resulted in erroneous biotypes and does not provide reliable results. Conclusion Previous studies associating G. vaginalis biotype with bacterial vaginosis were methodologically flawed, suggesting there is not an association of G. vaginalis biotypes and bacterial vaginosis. Sialidase activity was observed in 5 of the 8 biotypes.

  4. Lipase Induction in Mucor hiemalis.

    Science.gov (United States)

    Akhtar, M W; Mirza, A Q; Chughtai, M I

    1980-08-01

    The influence on lipase induction in Mucor hiemalis of different types of triglycerides containing mainly oleic acid (olive oil), erucic acid (mustard oil), or saturated fatty acids of 8 to 16 carbons (coconut oil) was studied. The fungus was grown in shake flasks in a fermentation medium containing peptone, minerals, and glucose or one of the oils as the carbon source. Maximum lipase was produced when the initial pH of the fermentation medium was kept at 4.0. Addition of Ca to the medium did not increase lipase production. The optimum pH for activity of both the mycelial and extracellular lipases was found to be 7.0. The fungus produced a significant amount of lipase in the presence of glucose, but the lipase activity increased markedly when olive oil was added to the medium at the beginning of the fermentation. Addition of olive oil at a later stage did not induce as much enzyme. Studies with washed mycelia showed that a greater amount of lipase was released when olive oil was present than when glucose was present. Among the various types of triglycerides used as the carbon source, olive oil was found to be most effective in inducing the lipase. Olive oil and mustard oil fatty acids inhibited the lipase more than those of coconut oil. The lipase induced by a particular type of triglyceride did not seem to be specific for the same triglyceride, nor was it inhibited specifically by it. Irrespective of the triglyceride used in the fermentation medium, the lipase produced was most active against coconut oil triglyceride, and this specificity, as shown by lipase activities in an n-heptane system, was not found to be due to a better emulsification of this oil. The lipase of M. hiemalis can be considered to be both constitutive and inducible.

  5. Enhancement of activity and selectivity of Candida rugosa lipase and Candida antarctica lipase A by bioimprinting and/or immobilization for application in the selective ethanolysis of fish oil.

    Science.gov (United States)

    Kahveci, Derya; Xu, Xuebing

    2011-10-01

    Candida rugosa lipase (CRL) and Candida antarctica lipase A (CALA) with improved activity and selectivity were prepared for use in organic solvent media. CRL bioimprinted with fatty acids exhibited eightfold enhanced transesterification activity in hexane. Combination of bioimprinting and coating with lecithin or with immobilization did not improve the activity further. CALA was immobilized with and without bioimprinting, none of which improved the activity. All modified lipases were tested for selective ethanolysis of fish oil to concentrate omega-3 polyunsaturated fatty acids (PUFA). None of the preparations, except the immobilized ones catalysed ethanolysis. Immobilized CRL-catalyzed ethanolysis giving 27% (v/v) ethyl esters (EE) in 48 h, of which 43 mol% was oleic acid but no PUFA was detected in the EE fraction. Fatty acid selectivity of CALA was significantly improved by immobilization combined with bioimprinting, resulting in 5.5-fold lower omega-3 PUFA in EE.

  6. Effect of oral mesoglycan on plasma lipoprotein concentration and on lipoprotein lipase activity in primary hyperlipoproteinemia.

    Science.gov (United States)

    Postiglione, A; De Simone, B; Rubba, P; Lamenza, F; Montefusco, S; Mastranzo, P

    1984-01-01

    Mesoglycan extracted from calf aorta was orally administered (96 mg/day) to 15 patients with primary hyperlipoproteinemia: 4 type IIA, 4 type IIB, 6 type IV and one type V. In the seven hypertriglyceridemic patients the drug after two months of treatment reduced total and VLDL-triglyceride from 701 mg/dl to 423 mg/dl (p less than 0.025) and from 562 mg/dl to 377 mg/dl (p less than 0.025) respectively and increased lipoprotein lipase activity from 19.7 mumol/l/min to 27.8 mumol/l/min (p less than 0.05). No change was observed in the group with type IIA-IIB hyperlipoproteinemia.

  7. Xanthine oxidase inhibitory activity of extracts prepared from Polygonaceae species.

    Science.gov (United States)

    Orbán-Gyapai, Orsolya; Lajter, Ildikó; Hohmann, Judit; Jakab, Gusztáv; Vasas, Andrea

    2015-03-01

    The xanthine oxidase (XO) inhibitory activity of aqueous and organic extracts of 27 selected species belonging in five genera (Fallopia, Oxyria, Persicaria, Polygonum and Rumex) of the family Polygonaceae occurring in the Carpathian Basin were tested in vitro. From different plant parts (aerial parts, leaves, flowers, fruits and roots), a total of 196 extracts were prepared by subsequent extraction with methanol and hot H2O and solvent-solvent partition of the MeOH extract yielding n-hexane, chloroform and 50% MeOH subextracts. It was found that the chloroform subextracts and/or the remaining 50% MeOH extracts of Fallopia species (F. bohemica, F. japonica and F. sachalinensis), Rumex species (R. acetosa, R. acetosella, R. alpinus, R. conglomeratus, R. crispus, R. hydrolapathus, R. pulcher, R. stenophyllus, R. thyrsiflorus, R. obtusifolius subsp. subalpinus, R. patientia) and Polygonum bistorta, Polygonum hydropiper, Polygonum lapathifolium and Polygonum viviparum demonstrated the highest XO inhibitory activity (>85% inhibition) at 400 µg/mL. The IC50 values of the active extracts were also determined. On the basis of the results, these plants, and especially P. hydropiper and R. acetosella, are considered worthy of activity-guided phytochemical investigations. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Effect of Water Clustering on the Activity of Candida antarctica Lipase B in Organic Medium

    Directory of Open Access Journals (Sweden)

    Sindrila Dutta Banik

    2017-07-01

    Full Text Available The effect of initial water activity of MTBE (methyl tert-butyl ether medium on CALB (Candida antarctica lipase B catalyzed esterification reaction is investigated using experimental methods and classical molecular dynamics (MD simulations. The experimental kinetic studies show that the initial reaction rate of CALB-catalyzed esterification reaction between butyric acid and ethanol decreases with increasing initial water activity of the medium. The highest rate of esterification is observed at the lowest water activity studied. MD simulations were performed to gain a molecular insight on the effect of initial water activity on the rate of CALB-catalyzed reaction. Our results show that hydration has an insignificant effect on the structure and flexibility of CALB. Rather, it appears that water molecules bind to certain regions (“hot spots” on the CALB surface and form clusters. The size of the water clusters at these hot spot regions gradually increase and expand with increasing water activity. Consequently, the surface area of CALB covered by the water molecules also increases. Specifically, our results indicate that a particular water cluster located close to the active site partially cover the binding pocket of substrate at high water activity. As a consequence, the effective concentration of substrate at the catalytic site decreases. Therefore, the reaction rate slows down with increasing water activity, which correlates well with the observed decrease in the experimentally determined initial reaction rate.

  9. Enzymatic activity of lipase in post-metamorphic phase bullfrogs Atividade enzimática da lipase em rã-touro na fase pós-metamórfica

    Directory of Open Access Journals (Sweden)

    Luís Gustavo Tavares Braga

    2006-10-01

    Full Text Available The knowledge of the digestive system of bullfrogs is an important step for the determination of their nutritional requirements throughout growth phases. With the objective of evaluating the enzymatic activity of lipase in the intestinal content of bullfrogs (Rana catesbeiana Shaw, 1802, 100 animals with median weight of 3.6 g were distributed in stalls under controlled temperature and photoperiod. The frogs, selected at the post-metamorphic phase, received commercial extruded diet ad libitum throughout the 87-day experiment. The collections of the intestinal content were performed by the desensitization of the frogs in ice and water at 0ºC and subsequent isolation of the small intestine. Determination of lipase activity was performed with a commercial enzymatic kit (Lipase-Bioclin, MG, Brazil, first measured in samples taken at day three (3.46 UI. During the initial phase the bullfrog possesses low lipase hydrolysis capacity was found, having a specific activity of 217 UI mg-1. In the subsequent period both lipase activity and specific lipase activity continuously increased. Lipase activity as a function of bullfrog weight fell after day twenty and reached 0.33 UI g-1, for frogs of medium weight (179 g. Feed for bullfrogs at the post-metamorphic phase weighing more than 10 g can have larger amounts of ingredients containg lipids, due to the increased digestive capacity of these frogs.O conhecimento do sistema digestório da rã-touro é um passo importante para a determinação de sua exigência nutricional nas diferentes fases de crescimento. Com o objetivo de avaliar a atividade enzimática da lipase no conteúdo intestinal da rã-touro (Rana catesbeiana Shaw, 1802, 100 animais com peso médio de 3,6 g foram distribuídos em baias-teste com temperatura e fotoperíodo controlados. As rãs, selecionadas na fase pos-metamórfica receberam ração extruzada comercial ad libitum. Durante 87 dias de experimento, 29 coletas (87 rãs foram feitas em

  10. The G-250A polymorphism in the hepatic lipase gene promoter is associated with changes in hepatic lipase activity and LDL cholesterol: The KANWU Study

    DEFF Research Database (Denmark)

    Lindi, Virpi; Schwab, Ursula; Louheranta, Anne;

    2007-01-01

    BACKGROUND AND AIMS: Hepatic lipase (HL) catalyzes the hydrolysis of triglycerides and phospholipids from lipoproteins, and promotes the hepatic uptake of lipoproteins. A common G-250A polymorphism in the promoter of the hepatic lipase gene (LIPC) has been described. The aim was to study...

  11. Activation of Hepatic Lipase Expression by Oleic Acid: Possible Involvement of USF1

    Directory of Open Access Journals (Sweden)

    Adrie J. M. Verhoeven

    2009-10-01

    Full Text Available Polyunsaturated fatty acids affect gene expression mainly through peroxisome proliferator-activated receptors (PPARs and sterol regulatory element binding proteins (SREBPs, but how monounsaturated fatty acids affect gene expression is poorly understood. In HepG2 cells, oleate supplementation has been shown to increase secretion of hepatic lipase (HL. We hypothesized that oleate affects HL gene expression at the transcriptional level. To test this, we studied the effect of oleate on HL promoter activity using HepG2 cells and the proximal HL promoter region (700 bp. Oleate increased HL expression and promoter activity 1.3–2.1 fold and reduced SREBP activity by 50%. Downregulation of SREBP activity by incubation with cholesterol+25-hydroxycholesterol had no effect on HL promoter activity. Overexpression of SREBP2, but not SREBP1, reduced HL promoter activity, which was effected mainly through the USF1 binding site at -307/-312. Oleate increased the nuclear abundance of USF1 protein 2.7 ± 0.6 fold, while USF1 levels were reduced by SREBP2 overexpression. We conclude that oleate increases HL gene expression via USF1. USF1 may be an additional fatty acid sensor in liver cells.

  12. Contractions activate hormone-sensitive lipase in rat muscle by protein kinase C and mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Donsmark, Morten; Langfort, Jozef; Holm, Cecilia

    2003-01-01

    Intramuscular triacylglycerol is an important energy store and is also related to insulin resistance. The mobilization of fatty acids from this pool is probably regulated by hormone-sensitive lipase (HSL), which has recently been shown to exist in muscle and to be activated by both adrenaline...... and contractions. Adrenaline acts via cAMP-dependent protein kinase (PKA). The signalling mediating the effect of contractions is unknown and was explored in this study. Incubated soleus muscles from 70 g male rats were electrically stimulated to perform repeated tetanic contractions for 5 min. The contraction...... of the inhibitors reduced adrenaline-induced HSL activation in soleus muscle. Both phorbol-12-myristate-13-acetate (PMA), which activates PKC and, in turn, ERK, and caffeine, which increases intracellular Ca2+ without eliciting contraction, increased HSL activity. Activated ERK increased HSL activity in supernatant...

  13. [Alpha-glucosidase inhibitory activity of Aeschynanthus maculatus].

    Science.gov (United States)

    Tian, Pu-yu; Kang, Wen-yi

    2012-10-01

    To study the inhibitory activity of Aeschynanthus maculatus on alpha-glucosidase. The inhibilitory model of in vitro alpha-glucosidase was established. Active extracts of A. maculatus were isolated and identified bymultiple chromatographic methods, and their molecular structures were identifiied by spectral techniques. Seven coumpounts were isolated from A. maculatus and isolated as lupeol(1), stigmasterol(2), ursolic acid(3), stigmast-5,22(E)-diene-3beta-ol(4), beta-daucosterol(5), 3-hydroxy-12-taraxasten-28-oic-acid(6) and oleanic acid(7). Compounds 1 (IC50 25.41 mg x L(-1)),3(IC0 4.42 mg L(-1)),4(IC50 11.50 mg x L(-1)),6(IC50 14.17 mg x L(-1)) and 7(IC50 2.88 mg x L(-1)) had higher inhibitory activities than that of acarbose (IC50 1103.01 mg x L(-1)) as the positive control drug. Compound 1-7 were isolated from this plant for the first time. Compound 6 was isolated from Gesneriaceae family for the first time. Compound 7 was isolated from Aeschynanthus genus for the first time.

  14. Immobilized MAS1 lipase showed high esterification activity in the production of triacylglycerols with n-3 polyunsaturated fatty acids.

    Science.gov (United States)

    Wang, Xiumei; Li, Daoming; Qu, Man; Durrani, Rabia; Yang, Bo; Wang, Yonghua

    2017-02-01

    Immobilization of lipase MAS1 from marine Streptomyces sp. strain W007 and its application in catalyzing esterification of n-3 polyunsaturated fatty acids (PUFA) with glycerol were investigated. The resin XAD1180 was selected as a suitable support for the immobilization of lipase MAS1, and its absorption ability was 75mg/g (lipase/resin ratio) with initial buffer pH value of 8.0. The thermal stability of immobilized MAS1 was improved significantly compared with that of the free lipase. Immobilized MAS1 had no regiospecificity in the hydrolysis of triolein. The highest esterification degree (99.31%) and TAG content (92.26%) by immobilized MAS1-catalyzed esterification were achieved under the optimized conditions, which were significantly better than those (82.16% and 47.26%, respectively) by Novozym 435. More than 92% n-3 PUFA was incorporated into TAG that had similar fatty acids composition to the substrate (n-3 PUFA). The immobilized MAS1 exhibited 50% of its initial activity after being used for five cycles.

  15. Biodiesel production with immobilized lipase: A review.

    Science.gov (United States)

    Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

    2010-01-01

    Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored.

  16. Covalent binding of hyper-activated Rhizomucor miehei lipase (RML) on hetero-functionalized siliceous supports.

    Science.gov (United States)

    Garmroodi, Maryam; Mohammadi, Mehdi; Ramazani, Ali; Ashjari, Maryam; Mohammadi, Javad; Sabour, Behrouz; Yousefi, Maryam

    2016-05-01

    Physical adsorption onto hydrophobic supports has proven to be an effective way to improve the activity of lipases. Covalent binding, on the other hand, enhances the active lifetime of the immobilized biocatalysts. To combine the benefits of adsorption and covalent binding, immobilization of RML on new hetero-functional supports are reported. For this, chemical modification of silica and silica mesoporous nanoparticles was performed by the simultaneous use of two coupling linkers; Octyltriethoxysilane (OTES) for hydrophobic interaction and glycidoxypropyltrimethoxylsilane (GPTMS) for covalent linkage of RML. Altering the GPTMS/OTES ratio makes possible to have different amount of octyl and epoxy groups on the supports. The results showed that immobilization of RML on octyl-functionalized supports produces specific activity almost 1.5-2 folds greater than the specific activity of the free enzyme. The observed hyper-activation decreased with increasing epoxy groups on the supports confirming the enhancement of covalent nature of the attachment. Leaching experiment was also confirmed positive effect of the presence of epoxy groups on the supports. Regarding the specific activity of the immobilized preparations and desorption percentages of RML from each support, the most suitable carrier obtains from the functionalization of the supports in presence of GPTMS and OTES in the ratio of 1:1.

  17. Molecular dynamics method on thermostability of cold active Lipase 5%基于分子动力学的脂肪酶 Lipase 5的热稳定性研究

    Institute of Scientific and Technical Information of China (English)

    吕建平; 魏冬青; 王永华; 徐沁

    2016-01-01

    天然的低温脂肪酶往往结构热稳定性比较差,制约了其长时间有效地发挥催化作用及保存。该研究以来源于白色念珠菌( Candida albicans )的低温脂肪酶Lipase 5为对象,运用相关分子动力学方法进行研究,提出了提高其热稳定性的理论策略。首先运用同源建模方法构建目标蛋白的三维结构模型;然后通过18 ns分子动力学模拟,锚定目标蛋白不稳定区域中柔性氨基酸(甘氨酸)的位置,并将这些柔性氨基酸位点突变为刚性氨基酸(脯氨酸);最后利用分子动力学模拟来验证这些突变对蛋白质热稳定性的影响。结果发现,将Lipase 5三维结构中的第279位甘氨酸突变为脯氨酸后,使得蛋白质热稳定性增强。这为类似低温脂肪酶的热稳定性改造的实验设计提供了理论支持。%The thermostability of naturally cold -adapted lipases is often relatively poor , limiting their long cata-lytic effect and long-term preservation.In the current study , one cold-adapted lipase Lipase 5 from Candida albicans was investigated by means of molecular dynamics method in order to improve its thermal stability.First the three-dimensional model of Lipase 5 was constructed by homology modeling.Then 18 ns molecular dynam-ics simulations were utilized to find the unstable region in Lipase 5 out of the protein active center with high con-formational fluctuations , and one possible mutant site 279-Gly was detected.It is finally proved that mutation of flexible 279-Gly to rigid Proline endows Lipase 5 enhances thermostability.Our studies may provide theoretical direction and support to design experiments of reforming thermal stability of cold active lipases.

  18. Xanthine oxidase inhibitory activity of compounds from Chythrantus claneianus

    Directory of Open Access Journals (Sweden)

    Anar Sahib Gojayev

    2013-03-01

    Full Text Available Phytochemical investigation of the stem bark and the trunk of Chythrantus claneianus led to the isolation of six known compounds named β-sitosterol (1, umbelliferone (2, scopoletin (3, benjaminamide (4, β-sitosterol-3-O-β-D-glucopyranoside (5 and Panconoside B (6. All these compounds were isolated for the first time from this plant species. The chemical structures of isolates were elucidated on the basis of 1 and 2 D-NMR spectra and other spectroscopic techniques including UV–vis, FT-IR, HR-ESIMS and HR-FABMS. The isolates were tested in vitro for their inhibitory properties towards xanthine oxidase enzyme. Compounds 2, 3 and 6 showed weak inhibi-tory activities on the enzyme with IC50 values ranging from 307 µM for com-pound 6 to 475 µM for compound 3, while the extract and compounds 1, 4 and 5 showed extremely weak activities with inhibition percentage less than 50%.

  19. Origin of aromatase inhibitory activity via proteochemometric modeling.

    Science.gov (United States)

    Simeon, Saw; Spjuth, Ola; Lapins, Maris; Nabu, Sunanta; Anuwongcharoen, Nuttapat; Prachayasittikul, Virapong; Wikberg, Jarl E S; Nantasenamat, Chanin

    2016-01-01

    Aromatase, the rate-limiting enzyme that catalyzes the conversion of androgen to estrogen, plays an essential role in the development of estrogen-dependent breast cancer. Side effects due to aromatase inhibitors (AIs) necessitate the pursuit of novel inhibitor candidates with high selectivity, lower toxicity and increased potency. Designing a novel therapeutic agent against aromatase could be achieved computationally by means of ligand-based and structure-based methods. For over a decade, we have utilized both approaches to design potential AIs for which quantitative structure-activity relationships and molecular docking were used to explore inhibitory mechanisms of AIs towards aromatase. However, such approaches do not consider the effects that aromatase variants have on different AIs. In this study, proteochemometrics modeling was applied to analyze the interaction space between AIs and aromatase variants as a function of their substructural and amino acid features. Good predictive performance was achieved, as rigorously verified by 10-fold cross-validation, external validation, leave-one-compound-out cross-validation, leave-one-protein-out cross-validation and Y-scrambling tests. The investigations presented herein provide important insights into the mechanisms of aromatase inhibitory activity that could aid in the design of novel potent AIs as breast cancer therapeutic agents.

  20. Inhibitory activity of xanthine oxidase by fractions Crateva adansonii

    Institute of Scientific and Technical Information of China (English)

    Abdullahi A; Kolo MZ; Hamzah RU; Jigam AA; Yahya A; Kabiru AY; Muhammad H; Sakpe S; Adefolalu FS; Isah MC

    2012-01-01

    Objective: To study the inhibitory effect of various extracts from Crateva adansonii (C. adansonii) used traditionally against several inflammatory diseases such as rheumatism, arthritis, and gout, was investigated on purified bovine milk xanthine oxidase (XO) activity. Methods:Xanthine oxidase inhibitory activity was assayed spectrophotometrically and the degree of enzyme inhibition was determined by measuring the increase in absorbance at 295 nm associated with uric acid formation. Enzyme kinetics was carried out using Lineweaver-Burk plots using xanthine as the substrate. Results: Among the fractions tested, the chloroform fraction exhibited highest potency (IC50 20.2±1.6 μg/mL) followed by the petroleum ether (IC50 30.1±2.2 μg/mL), ethyl acetate (IC50 43.9±1.4 μg/mL) and residual (IC50 98.0±3.3 μg/mL) fractions. The IC50 value of allopurinol used, as the standard was 5.7±0.3 μg/mL. Conclusions: Enzyme inhibition mechanism indicated that the mode of inhibition was of a mixed type. Our findings suggest that the therapeutic use of these plants may be due to the observed Xanthine oxidase inhibition, thereby supporting their use in traditional folk medicine against inflammatory-related diseases, in particular, gout.

  1. Low Serum Lysosomal Acid Lipase Activity Correlates with Advanced Liver Disease

    Directory of Open Access Journals (Sweden)

    Eyal Shteyer

    2016-02-01

    Full Text Available Fatty liver has become the most common liver disorder and is recognized as a major health burden in the Western world. The causes for disease progression are not fully elucidated but lysosomal impairment is suggested. Here we evaluate a possible role for lysosomal acid lipase (LAL activity in liver disease. To study LAL levels in patients with microvesicular, idiopathic cirrhosis and nonalcoholic fatty liver disease (NAFLD. Medical records of patients with microvesicular steatosis, cryptogenic cirrhosis and NAFLD, diagnosed on the basis of liver biopsies, were included in the study. Measured serum LAL activity was correlated to clinical, laboratory, imaging and pathological data. No patient exhibited LAL activity compatible with genetic LAL deficiency. However, serum LAL activity inversely predicted liver disease severity. A LAL level of 0.5 was the most sensitive for detecting both histologic and noninvasive markers for disease severity, including lower white blood cell count and calcium, and elevated γ-glutamyltransferase, creatinine, glucose, glycated hemoglobin, uric acid and coagulation function. Serum LAL activity <0.5 indicates severe liver injury in patients with fatty liver and cirrhosis. Further studies should define the direct role of LAL in liver disease severity and consider the possibility of replacement therapy.

  2. Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification.

    Science.gov (United States)

    Silva, Jane E S; Jesus, Paulo C

    2003-06-01

    In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa) were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25 C in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester.

  3. Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jane E.S.; Jesus, Paulo C. [Universidade Regional de Blumenau, SC (Brazil). Dept. de Quimica]. E-mail: pcj@furb.rct-sc.br

    2003-06-01

    In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa) were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25 deg C in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester. (author)

  4. Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

    Directory of Open Access Journals (Sweden)

    Silva Jane E. S.

    2003-01-01

    Full Text Available In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25ºC in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester.

  5. Plant lipases: partial purification of Carica papaya lipase.

    Science.gov (United States)

    Rivera, Ivanna; Mateos-Díaz, Juan Carlos; Sandoval, Georgina

    2012-01-01

    Lipases from plants have very interesting features for application in different fields. This chapter provides an overview on some of the most important aspects of plant lipases, such as sources, applications, physiological functions, and specificities. Lipases from laticifers and particularly Carica papaya lipase (CPL) have emerged as a versatile autoimmobilized biocatalyst. However, to get a better understanding of CPL biocatalytic properties, the isolation and purification of individual C. papaya lipolytic enzymes become necessary. In this chapter, a practical protocol for partial purification of the latex-associated lipolytic activity from C. papaya is given.

  6. Aspects of the regulation of liver lipase

    NARCIS (Netherlands)

    G.C. Schoonderwoerd (Kees)

    1986-01-01

    textabstractIt is evident that factors that influence the activity of liver lipase could be important because of the role of liver lipase in HDL-cholesterol metabolism. At the start of this study not much was known about the regulation of liver lipase. The activity had been found to be decreased aft

  7. Cross-linked enzyme aggregates (CLEAs) of Pencilluim notatum lipase enzyme with improved activity, stability and reusability characteristics.

    Science.gov (United States)

    Rehman, Saima; Bhatti, Haq Nawaz; Bilal, Muhammad; Asgher, Muhammad

    2016-10-01

    Cross-linked enzyme aggregates (CLEAs) are considered as an effective tool for the immobilization of enzyme. In this study, Pencillium notatum lipase (PNL) was immobilized as carrier free cross-linked enzyme aggregates using glutaraldehyde (GLA) and Ethylene glycol-bis [succinic acid N-hydroxysuccinimide] (EG-NHS) as cross-linking agents. The optimal conditions for the synthesis of an efficient lipase CLEAs such as precipitant type, the nature and amount of cross-linking reagent, and cross-linking time were optimized. The recovered activities of CLEAs were considerably dependent on the concentration of GLA; however, the activity recovery was not severely affected by EG-NHS as a mild cross-linker. The EG-NHS aggregates displayed superior hydrolytic (52.08±2.52%) and esterification (64.42%) activities as compared to GLA aggregates which showed 23.8±1.86 and 34.54% of hydrolytic and esterification activity, respectively. Morphological analysis by fluorescence and scanning electron microscope revealed that EG-NHS aggregates were smaller in size with larger surface area compared to GLA aggregates. The pH optima of both types of CLEAs were displaced to slightly alkaline region and higher temperature as compared to native enzyme. Highest enzyme activity of CLEAs was achieved at the pH of 9.0 and 42°C temperature. Moreover, a significant improvement in the thermal resistance was also recorded after immobilization. After ten reusability cycles in aqueous medium, GLA and EG-NHS cross-linked lipase CLEAs preserved 63.62% and 70.9% of their original activities, respectively. The results suggest that this novel CLEA-lipase is potentially usable in many industrial applications.

  8. Lipase and invertase activities in midgut and salivary glands of Chilo suppressalis (Walker (Lepidoptera, Pyralidae, rice striped stem borer

    Directory of Open Access Journals (Sweden)

    A Zibaee

    2008-11-01

    Full Text Available The rice striped stem borer, Chilo supprressalis, was introduced to Iran in 1973 where it is now widely distributed and causes severe damages. Lipases, which catalyses the hydrolysis of fatty acid ester bonds, are widely distributed among animals, plants and microorganisms. Invertases (β-fructofuranosidase are glycosidehydrolases that catalyze the cleavage of sucrose (β-D-glucopyranosyl-S-D-fructofuranoside into the monosaccharides glucose and fructose. Laboratory-reared 4th instar larvae were randomly selected, their midgut and salivary glands were removed by dissection under a light microscope and lipase and invertase activities were assayed. The activity of lipase/invertase in the midgut and salivary gland were 0.49/0.27 and 0.35/0.23 μmol/min/mg protein, respectively. The optimum pH and temperature for both the two enzymes were determined to be 10-11 and 37-40 °C, which is consistent with pH and temperature values already observed in Lepidoptera. The enzyme activity was reduced by addition of NaCl, KCl, MgCl2, SDS, urea and plant extracts from Artemisia annua, but not by CaCl2 which enhanced enzyme activity. Pest control with usage of resistant varieties of plants is one of the most important practices that are dependant on inhibitors already present in nature. Hence, characterization of insect digestive enzymes, especially examination of inhibition effects on enzyme activity, could be useful in developing new strategies for pest control.

  9. Purification and characterization of a new cold active lipase, EnL A ...

    African Journals Online (AJOL)

    SONU

    2015-06-03

    Jun 3, 2015 ... carried out with the lipase production medium optimized using. Response ... isopropanol, diethyl ether, DMSO, butanol and acetone at a concentration of 10 ... and grease content using partition gravimetric method (Kirschman.

  10. Construction of the yeast whole-cell Rhizopus oryzae lipase biocatalyst with high activity

    Institute of Scientific and Technical Information of China (English)

    Mei-ling CHEN; Qin GUO; Rui-zhi WANG; Juan XU; Chen-wei ZHOU; Hui RUAN; Guo-qing HE

    2011-01-01

    Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed.Compared with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate.To our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction.Consequently,the yeast whole-cell ROL biocatalyst was constructed with high activity.The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 ℃.Furthermore,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.

  11. Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

    OpenAIRE

    Silva Jane E. S.; Jesus Paulo C.

    2003-01-01

    In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa) were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25ºC in hexane as solvent. The best results were obtained with Mucor jav...

  12. Native New Zealand plants with inhibitory activity towards Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Swift Simon

    2010-06-01

    Full Text Available Abstract Background Plants have long been investigated as a source of antibiotics and other bioactives for the treatment of human disease. New Zealand contains a diverse and unique flora, however, few of its endemic plants have been used to treat tuberculosis. One plant, Laurelia novae-zelandiae, was reportedly used by indigenous Maori for the treatment of tubercular lesions. Methods Laurelia novae-zelandiae and 44 other native plants were tested for direct anti-bacterial activity. Plants were extracted with different solvents and extracts screened for inhibition of the surrogate species, Mycobacterium smegmatis. Active plant samples were then tested for bacteriostatic activity towards M. tuberculosis and other clinically-important species. Results Extracts of six native plants were active against M. smegmatis. Many of these were also inhibitory towards M. tuberculosis including Laurelia novae-zelandiae (Pukatea. M. excelsa (Pohutukawa was the only plant extract tested that was active against Staphylococcus aureus. Conclusions Our data provide support for the traditional use of Pukatea in treating tuberculosis. In addition, our analyses indicate that other native plant species possess antibiotic activity.

  13. AKTIVITAS HIDROLISIS ENZIM LIPASE DARI KENTOS KELAPA TERHADAP MINYAK KELAPA Hidrolysis Activity of Lipase Enzyme from Coconut Houstorium for Coconut Oil

    Directory of Open Access Journals (Sweden)

    Mohammad Su’i

    2012-05-01

    Full Text Available This research was aimed to study hydrolysis conditions of houstorium lipases enzyme using coconut oil as substrate. Hydrolysis conditions studied were substrate (coconut oil concentration, enzyme substrate ratio, duration of hydro- lysis and effect of stirring to hydrolysis. The results show  that lipase of coconut houstorium may be optimally used at a coconut oil concentration of 10 %, enzyme to substrate ratio of 3 : 10 (v/v and hydrolysis for 60 minutes with stirring. ABSTRAK Penelitian ini mempelajari kondisi hidrolisis minyak kelapa yang optimum menggunakan enzim lipase dari kentos kelapa. Kondisi hidrolisis yang dipelajari meliputi konsentrasi substrat optium, perbandingan enzim : substrat dan lama hidrolisis yang optimum serta pengaruh pengadukan selama hidrolisis. Hasil penelitian menunjukkan bahwa, hidrolisis minyak kelapa menggunakan enzim lipase kentos kelapa menghasilkan asam lemak bebas paling banyak pada kon- sentrasi substrat (minyak kelapa 10 %, perbandingan enzim : substrat yaitu 3 : 10 (v/v, lama hidroloisa 60 menit dan dilakukan pengadukan selama hidrolisis.

  14. Comparative analyses of lipoprotein lipase, hepatic lipase, and endothelial lipase, and their binding properties with known inhibitors.

    Directory of Open Access Journals (Sweden)

    Ziyun Wang

    Full Text Available The triglyceride lipase gene subfamily plays a central role in lipid and lipoprotein metabolism. There are three members of this subfamily: lipoprotein lipase, hepatic lipase, and endothelial lipase. Although these lipases are implicated in the pathophysiology of hyperlipidemia and atherosclerosis, their structures have not been fully solved. In the current study, we established homology models of these three lipases, and carried out analysis of their activity sites. In addition, we investigated the kinetic characteristics for the catalytic residues using a molecular dynamics simulation strategy. To elucidate the molecular interactions and determine potential key residues involved in the binding to lipase inhibitors, we analyzed the binding pockets and binding poses of known inhibitors of the three lipases. We identified the spatial consensus catalytic triad "Ser-Asp-His", a characteristic motif in all three lipases. Furthermore, we found that the spatial characteristics of the binding pockets of the lipase molecules play a key role in ligand recognition, binding poses, and affinities. To the best of our knowledge, this is the first report that systematically builds homology models of all the triglyceride lipase gene subfamily members. Our data provide novel insights into the molecular structures of lipases and their structure-function relationship, and thus provides groundwork for functional probe design towards lipase-based therapeutic inhibitors for the treatment of hyperlipidemia and atherosclerosis.

  15. Altering the interfacial activation mechanism of a lipase by solid-phase selective chemical modification.

    Science.gov (United States)

    López-Gallego, Fernando; Abian, Olga; Guisán, Jose Manuel

    2012-09-04

    This study presents a combined protein immobilization, directed mutagenesis, and site-selective chemical modification approach, which was used to create a hyperactivated semisynthetic variant of BTL2. Various alkane chains were tethered at three different positions in order to mimic the lipase interfacial activation exogenously triggered by detergents. Optimum results were obtained when a dodecane chain was introduced at position 320 by solid-phase site-selective chemical modification. The resulting semisynthetic variant showed a 2.5-fold higher activity than the wild-type nonmodified variant in aqueous conditions. Remarkably, this is the maximum hyperactivation ever observed for BTL2 in the presence of detergents such as Triton X-100. We present evidence to suggest that the endogenous dodecane chain hyperactivates the enzyme in a similar fashion as an exogenous detergent molecule. In this way, we also observe a faster irreversible enzyme inhibition and an altered detergent sensitivity profile promoted by the site-selective chemical modification. These findings are also supported by fluorescence studies, which reveal that the structural conformation changes of the semisynthetic variant are different to those of the wild type, an effect that is more pronounced in the presence of detergent. Finally, the optimal immobilized semisynthetic variant was successfully applied to the selective synthesis of oxiran-2-yl butyrate. Significantly, this biocatalyst is 12-fold more efficient than the immobilized wild-type enzyme, producing the S-enantiomer with higher enantiospecificity (ee = 92%).

  16. Activation and inhibition of Candida rugosa and Bacillus-related lipases by saturated fatty acids, evaluated by a new colorimetric microassay.

    Science.gov (United States)

    Ruiz, Cristian; Falcocchio, Serena; Xoxi, Entela; Pastor, F I Javier; Diaz, Pilar; Saso, Luciano

    2004-06-11

    Research on lipase inhibitors could help in the therapy of diseases caused by lipase-producing microorganisms and in the design of novel lipase substrate specificities for biotechnology. Here we report a fast and sensitive colorimetric microassay that is low-cost and suitable for high-throughput experiments for the evaluation of lipase activity and inhibition. Comparison of Candida rugosa activity and inhibition with previous HPLC results validated the method, and revealed the importance of the reaction mixture composition. The assay was used to evaluate the effect of saturated fatty acids on Bacillus-related lipases. Cell-bound esterases were strongly inhibited by fatty acids, suggesting a negative feedback regulation by product, and a role of these enzymes in cell membrane turnover. Bacillus subtilis LipA was moderately activated by low concentrations of fatty acids and was inhibited at greater concentrations. LipB-like esterases were highly activated by myristic and lauric acids and were only slightly inhibited by high capric acid concentrations. Such an activation, reported here for the first time in bacterial lipases, seems to be part of a regulatory system evolved to ensure a high use of carbon sources, and could be related to the successful adaptation of Bacillus strains to nutrient-rich environments with strong microbial competition.

  17. Gastric Lipase Secretion in Children with Gastritis

    OpenAIRE

    Krystyna Sztefko; Krzysztof Fyderek; Andrzej Zając; Andrzej Wędrychowicz; Iwona Rogatko; Tomasik, Przemyslaw J

    2013-01-01

    Gastric lipase is one of the prepancreatic lipases found in some mammalian species and in humans. Our knowledge of the hormonal regulation of gastric lipase secretion in children and adolescents is still very limited. The aim of this study was to compare the activity of human gastric lipase (HGL) in gastric juice in healthy adolescents and in patients with gastritis. The adolescents were allocated to three groups: the first including patients with Helicobacter pylori gastritis (HPG; n = 10), ...

  18. A Sensitive Microplate Assay for Lipase Activity Measurement Using Olive Oil Emulsion Substrate: Modification of the Copper Soap Colorimetric Method.

    Science.gov (United States)

    Mustafa, Ahmad; Karmali, Amin; Abdelmoez, Wael

    2016-01-01

    The present work involves a sensitive high-throughput microtiter plate based colorimetric assay for estimating lipase activity using cupric acetate pyridine reagent (CAPR). In the first approach, three factors two levels factorial design methodology was used to evaluate the interactive effect of different parameters on the sensitivity of the assay method. The optimization study revealed that the optimum CAPR concentration was 7.5% w/v, the optimum solvent was heptane and the optimum CAPR pH was 6. In the second approach, the optimized colorimetric microplate assay was used to measure lipase activity based on enzymatic hydrolysis of olive oil emulsion substrate at 37°C and 150 rpm. The emulsion substrates were formulated by using olive oil, triton X-100 (10% v/v in pH 8) and sodium phosphate buffer of pH 8 in ratio of 1:1:1 in the case of Candida sp. lipase. While in the case of immobilized lipozyme RMIM, The emulsion substrates were formulated by using olive oil, triton X-100 (1% v/v in pH 8) and sodium phosphate buffer of pH 8 in ratio of 2:1:1. Absorbance was measured at 655 nm. The stability of this assay (in terms of colored heptane phase absorbance readings) retained more than 92.5% after 24 h at 4°C compared to the absorbance readings measured at zero time. In comparison with other lipase assay methods, beside the developed sensitivity, the reproducibility and the lower limit of detection (LOD) of the proposed method, it permits analyzing of 96 samples at one time in a 96-well microplate. Furthermore, it consumes small quantities of chemicals and unit operations.

  19. Inhibitory effects of ionic liquids on the lactic dehydrogenase activity.

    Science.gov (United States)

    Dong, Xing; Fan, Yunchang; Zhang, Heng; Zhong, Yingying; Yang, Yang; Miao, Juan; Hua, Shaofeng

    2016-05-01

    Ionic liquids (ILs) were widely used in scientific and industrial application and have been reported to possess potential toxicity to the environment and human health. The effects of six typical N-methylimidazolium-based ILs ([Cnmim]X, n=4, 6, 8; X=Br(-), Cl(-), BF4(-), CF3SO3(-)) on the lactic dehydrogenase (LDH) activity and the molecular interaction mechanism of ILs and the LDH were investigated with the aid of spectroscopic techniques. Experimental results showed that the LDH activity was inhibited in the presence of ILs. For the ILs with the same anion but different cations, their inhibitory ability on the LDH activity increased with increasing the alkyl chain length on the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of LDH with the addition of ILs. Both positive ΔH and ΔS suggested that hydrophobicity was the major driven force in the interaction process as expected.

  20. Lipase catalyzed esterification of glycidol in nonaqueous solvents: solvent effects on enzymatic activity.

    Science.gov (United States)

    Martins, J F; de Sampaio, T C; de Carvalho, I B; Barreiros, S

    1994-06-05

    We studied the effect of organic solvents on the kinetics of porcine pancreatic lipase (pp) for the resolution of racemic glycidol through esterification with butyric acid. We quantified ppl hydration by measuring water sorption isotherms for the enzyme in the solvents/mixtures tested. The determination of initial rates as a function of enzyme hydration revealed that the enzyme exhibits maximum apparent activity in the solvents/mixtures at the same water content (9% to 11% w/w) within the associated experimental error. The maximum initial rates are different in all the media and correlate well with the logarithm of the molar solubility of water in the media, higher initial rates being observed in the solvents/mixtures with lower water solubilities. The data for the mixtures indicate that ppl apparent activity responds to bulk property of the solvent. Measurements of enzyme particle sizes in five of the solvents, as function of enzyme hydration, revealed that mean particle sizes increased with enzyme hydration in all the solvents, differences between solvents being more pronounced at enzyme hydration levels close to 10%. At this hydration level, solvents having a higher water content lead to lower reaction rates; these are the solvents where the mean enzyme particle sizes are greater. Calculation of the observable modulus indicates there are no internal diffusion limitations. The observed correlation between changes in initial rates and changes in external surface area of the enzyme particles suggests that interfacial activation of ppl is only effective at the external surface of the particles. Data obtained for the mixtures indicate that ppl enantioselectivity depends on specific solvent-enzyme interactions. We make reference to ppl hydration and activity in supercritical carbon dioxide.

  1. Enhanced activity of Rhizomucor miehei lipase by directed evolution with simultaneous evolution of the propeptide.

    Science.gov (United States)

    Wang, Jue; Wang, Dan; Wang, Bo; Mei, Zhuo-Hang; Liu, Ji; Yu, Hong-Wei

    2012-10-01

    Propeptides are short sequences that facilitate the folding of their associated proteins. The present study found that the propeptide of Rhizomucor miehei lipase (RML) was not proteolytically removed in Escherichia coli. Moreover, RML was not expressed if the propeptide was removed artificially during the cloning process in E. coli. This behavior in E. coli permitted the application of directed evolution to full-length RML, which included both propeptide and catalytic domain, to explore the role played by the propeptide in governing enzyme activity. The catalytic rate constant, k (cat), of the most active mutant RML protein (Q5) was increased from 10.63 ± 0.80 to 71.44 ± 3.20 min(-1) after four rounds of screening. Sequence analysis of the mutant displayed three mutations in the propeptide (L57V, S65A, and V67A) and two mutations in the functional region (I111T and S168P). This result showed that improved activity was obtained with essential involvement by mutations in the propeptide, meaning that the majority of mutants with enhanced activity had simultaneous mutations in propeptide and catalytic domains. This observation leads to the hypothesis that directed evolution has simultaneous and synergistic effects on both functional and propeptide domains that arise from the role played by the propeptide in the folding and maturation of the enzyme. We suggest that directed evolution of full-length proteins including their propeptides is a strategy with general validity for extending the range of conformations available to proteins, leading to the enhancement of the catalytic rates of the enzymes.

  2. Role of the NC-loop in catalytic activity and stability in lipase from Fervidobacterium changbaicum.

    Directory of Open Access Journals (Sweden)

    Binchun Li

    Full Text Available Flexible NC-loops between the catalytic domain and the cap domain of the α/β hydrolase fold enzymes show remarkable diversity in length, sequence, and configuration. Recent investigations have suggested that the NC-loop might be involved in catalysis and substrate recognition in many enzymes from the α/β hydrolase fold superfamily. To foster a deep understanding of its role in catalysis, stability, and divergent evolution, we here systemically investigated the function of the NC-loop (residues 131-151 in a lipase (FClip1 from thermophilic bacterium Fervidobacterium changbaicum by loop deletion, alanine-scanning mutagenesis and site-directed mutagenesis. We found that the upper part of the NC-loop (residues 131-138 was of great importance to enzyme catalysis. Single substitutions in this region could fine-tune the activity of FClip1 as much as 41-fold, and any deletions from this region rendered the enzyme completely inactive. The lower part of the NC-loop (residues 139-151 was capable of enduring extensive deletions without loss of activity. The shortened mutants in this region were found to show both improved activity and increased stability simultaneously. We therefore speculated that the NC-loop, especially the lower part, would be a perfect target for enzyme engineering to optimize the enzymatic properties, and might present a hot zone for the divergent evolution of α/β hydrolases. Our findings may provide an opportunity for better understanding of the mechanism of divergent evolution in the α/β hydrolase fold superfamily, and may also guide the design of novel biocatalysts for industrial applications.

  3. Lipase-catalyzed biodiesel production from waste activated bleaching earth as raw material in a pilot plant.

    Science.gov (United States)

    Park, Enoch Y; Sato, Masayasu; Kojima, Seiji

    2008-05-01

    The production of fatty acid methyl esters (FAMEs) from waste activated bleaching earth (ABE) discarded by the crude oil refining industry using lipase from Candida cylindracea was investigated in a 50-L pilot plant. Diesel oil or kerosene was used as an organic solvent for the transesterification of triglycerides embedded in the waste ABE. When 1% (w/w) lipase was added to waste ABE, the FAME content reached 97% (w/w) after reaction for 12 h at 25 degrees C with an agitation rate of 30 rpm. The FAME production rate was strongly dependent upon the amount of enzyme added. Mixtures of FAME and diesel oil at ratios of 45:55 (BDF-45) and 35:65 (BDF-35) were assessed and compared with the European specifications for biodiesel as automotive diesel fuel, as defined by pr EN 14214. The biodiesel quality of BDF-45 met the EN 14214 standard. BDF-45 was used as generator fuel, and the exhaust emissions were compared with those of diesel oil. The CO and SO2 contents were reduced, but nitrogen oxide emission increased by 10%. This is the first report of a pilot plant study of lipase-catalyzed FAME production using waste ABE as a raw material. This result demonstrates a promising reutilization method for the production of FAME from industrial waste resources containing vegetable oils for use as a biodiesel fuel.

  4. Effects of long-term ethanol consumption on jejunal lipase and disaccharidase activities in male and female rats

    Institute of Scientific and Technical Information of China (English)

    Chi-Chang Huang; Jiun-Rong Chen; Chieh-Chung Liu; Kung-Tung Chen; Ming-Jer Shieh; Suh-Ching Yang

    2005-01-01

    AIM: To study the effect of long-term ethanol consumption on jejunal lipase and disaccharidase (sucrase, maltase,and lactase) activities in rats and its gender difference. METHODS: Age-matched male and female Wistar rats were fed control or ethanol-containing liquid diets for 12 wk following the Lieber-DeCarli model. According to both theplasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, 40 rats were divided into four groups as follows: male control group (MC), male ethanol group (ME), female control group (FC), and female ethanol group (FE).RESULTS: After ethanol feeding for 12 wk, the results revealed that plasma AST and ALT activities of group MEwere significantly increased by 58% and 92%, respectively,than those of group MC (P<0.05). Similarly, plasma AST and ALT activities of group FE were also significantly increased by 61% and 188%, respectively, than those of group FC (P<0.05). Fat accumulation was observed in both ethanol treated groups, while fatty changes were more severe in group FE than those in group ME. The induction of hepatic microsomal cytochrome P450 2E1 (CYP2E1) was obviously seen in group ME and group FE, but was not detected in group MC and group FC. Jejunal lipase activity of group ME was significantly increased by 1.25-fold than that of group MC (P<0.05). In contrast to, sucrase, maltase, and lactase activities of group ME were significantly decreased by 63%, 62% and 67%, respectively, than those of group MC (P<0.05). Similarly, activities of these three enzymes of group FE were also significantly decreased by 43%, 46% and 52%, respectively, than those of group FC (P<0.05).There were no significant epithelial changes of the duodenal mucosa in any group.CONCLUSION: Long-term ethanol consumption significantly can increase jejunal lipase and decrease jejunal disaccharidase activities in both male and female rats.

  5. Synthesis of mangiferin derivates and study their potent PTP1B inhibitory activity

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Protein tyrosine phosphatase 1B (PTP1B) has received considerable attention from the drug industry as a potential treatment fordiabetes mellitus. Mangiferin has been reported to possess significant antidiabetic activity. Based on the previous study, eight new mangiferin derivates were synthesized and evaluated for their PTP1B inhibitory activity. Some of them displayed good inhibitory activity on PTP1B.

  6. α-Glucosidase inhibitory activity of selected Malaysian plants

    Directory of Open Access Journals (Sweden)

    Dzatil Awanis Mohd Bukhari

    2017-01-01

    Full Text Available Diabetes is a common metabolic disease indicated by unusually high plasma glucose level that can lead to major complications such as diabetic neuropathy, retinopathy, and cardiovascular diseases. One of the effective therapeutic managements of the disease is to reduce postprandial hyperglycemia through inhibition of α-glucosidase, a carbohydrate-hydrolyzing enzyme to retard overall glucose absorption. In recent years, a plenty of research works have been conducted looking for novel and effective α-glucosidase inhibitors (AGIs from natural sources as alternatives for the synthetic AGI due to their unpleasant side effects. Plants and herbs are rich with secondary metabolites that have massive pharmaceutical potential. Besides, studies showed that phytochemicals such as flavonoids, alkaloids, terpenoids, anthocyanins, glycosides, and phenolic compounds possess significant inhibitory activity against α-glucosidase enzyme. Malaysia is a tropical country that is rich with medicinal herbs. In this review, we focus on eight Malaysian plants with the potential as AGI to develop a potential functional food or lead compounds against diabetes.

  7. Engineering a lipase B from Candida antactica with efficient perhydrolysis performance by eliminating its hydrolase activity

    Science.gov (United States)

    Wang, Xu-Ping; Zhou, Peng-Fei; Li, Zhi-Gang; Yang, Bo; Hollmann, Frank; Wang, Yong-Hua

    2017-01-01

    A Ser105Ala mutant of the lipase B from Candida antarctica enables ‘perhydrolase-only’ reactions. At the example of the chemoenzymatic Baeyer-Villiger oxidation of cyclohexanone, we demonstrate that with this mutant selective oxidation can be achieved in deep eutectic solvent while essentially eliminating the undesired hydrolysis reaction of the product. PMID:28317884

  8. Highly Selective, Reversible Inhibitor Identified by Comparative Chemoproteomics Modulates Diacylglycerol Lipase Activity in Neurons

    NARCIS (Netherlands)

    M.P. Baggelaar; P.J.P. Chameau; V. Kantae; J. Hummel; K.L. Hsu; F. Janssen; T. van der Wel; M. Soethoudt; H. Deng; H. den Dulk; M. Allarà; B.I. Florea; V. Di Marzo; W.J. Wadman; C.G. Kruse; H.S. Overkleeft; T. Hankemeier; T.R. Werkman; B.F. Cravatt; M. van der Stelt

    2015-01-01

    Diacylglycerol lipase (DAGL)-alpha and -beta are enzymes responsible for the biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG). Selective and reversible inhibitors are required to study the function of DAGLs in neuronal cells in an acute and temporal fashion, but they are currently l

  9. Characterization of a cold-active lipase from Psychrobacter cryohalolentis K5(T) and its deletion mutants.

    Science.gov (United States)

    Novototskaya-Vlasova, K A; Petrovskaya, L E; Rivkina, E M; Dolgikh, D A; Kirpichnikov, M P

    2013-04-01

    A gene coding for cold-active lipase from the psychrotrophic Gram-negative bacterium Psychrobacter cryohalolentis K5(T) isolated from a Siberian cryopeg has been cloned and expressed in Escherichia coli. The recombinant protein Lip1Pc with a 6× histidine tag at its C-terminus was purified by nickel affinity chromatography. With p-nitrophenyl dodecanoate (C12) as a substrate, the purified recombinant protein displayed maximum lipolytic activity at 25°C and pH 8.0. Increasing the temperature above 40°C and addition of various metal ions and organic solvents inhibited the enzymatic activity of Lip1Pc. Most nonionic detergents, such as Triton X-100 and Tween 20, slightly increased the lipase activity, while SDS completely inhibited it. To investigate the functional significance of the Lip1Pc N-terminal domain, we constructed five deletion mutants of this protein. The ND1 and ND2 mutants displayed specific activity reduced by 30-35%, while other truncated proteins were completely inactive. Both mutants demonstrated increased activity towards p-nitrophenyl decanoate (C10) and impaired utilization of C16 substrate. Although optimum reaction temperature of ND2 lowered to 20°C, it displayed enhanced stability by 44% after incubation at 40°C. The results prove that the N-terminal domain of Lip1Pc has a fundamental impact on the activity and stability of the protein.

  10. Inhibitory Activities of Zygophyllum album: A Natural Weight-Lowering Plant on Key Enzymes in High-Fat Diet-Fed Rats

    Directory of Open Access Journals (Sweden)

    Kais Mnafgui

    2012-01-01

    Full Text Available Obesity is a serious health problem that increased risk for many complications, including diabetes and cardiovascular disease. The results showed EZA, which found rich in flavonoids and phenolic compounds, exhibited an inhibitory activity on pancreatic lipase in vitro with IC50 of 91.07 μg/mL. In vivo administration of this extract to HFD-rats lowered body weight and serum leptin level; and inhibited lipase activity of obese rats by 37% leading to notable decrease of T-Ch, TGs and LDL-c levels accompanied with an increase in HDL-c concentration in serum and liver of EZA treated HFD-rats. Moreover, the findings revealed that EZA helped to protect liver tissue from the appearance of fatty cysts. Interestingly, supplementation of EZA modulated key enzyme related to hypertension such as ACE by 36% in serum of HFD animals and improve some of serum electrolytes such as Na+, K+, Cl−, Ca2+ and Mg2+. Moreover, EZA significantly protected the liver-kidney function by reverted back near to normal the values of the liver-kidney dysfunction indices AST&ALT, ALP, CPK and GGT activities, decreased T-Bili, creat, urea and uric acid rates. In conclusion, these results showed a strong antihypelipidemic effect of EZA which can delay the occurrence of dislipidemia and hypertension.

  11. Inhibitory Activities of Zygophyllum album: A Natural Weight-Lowering Plant on Key Enzymes in High-Fat Diet-Fed Rats

    Science.gov (United States)

    Mnafgui, Kais; Hamden, Khaled; Ben Salah, Hichem; Kchaou, Mouna; Nasri, Mbarek; Slama, Sadok; Derbali, Fatma; Allouche, Noureddine; Elfeki, Abdelfattah

    2012-01-01

    Obesity is a serious health problem that increased risk for many complications, including diabetes and cardiovascular disease. The results showed EZA, which found rich in flavonoids and phenolic compounds, exhibited an inhibitory activity on pancreatic lipase in vitro with IC50 of 91.07 μg/mL. In vivo administration of this extract to HFD-rats lowered body weight and serum leptin level; and inhibited lipase activity of obese rats by 37% leading to notable decrease of T-Ch, TGs and LDL-c levels accompanied with an increase in HDL-c concentration in serum and liver of EZA treated HFD-rats. Moreover, the findings revealed that EZA helped to protect liver tissue from the appearance of fatty cysts. Interestingly, supplementation of EZA modulated key enzyme related to hypertension such as ACE by 36% in serum of HFD animals and improve some of serum electrolytes such as Na+, K+, Cl−, Ca2+ and Mg2+. Moreover, EZA significantly protected the liver-kidney function by reverted back near to normal the values of the liver-kidney dysfunction indices AST&ALT, ALP, CPK and GGT activities, decreased T-Bili, creat, urea and uric acid rates. In conclusion, these results showed a strong antihypelipidemic effect of EZA which can delay the occurrence of dislipidemia and hypertension. PMID:23258993

  12. A thiol-activated lipase from Trichosporon asahii MSR 54: detergent compatibility and presoak formulation for oil removal from soiled cloth at ambient temperature.

    Science.gov (United States)

    Kumar, S Suresh; Kumar, Lalit; Sahai, Vikram; Gupta, Rani

    2009-03-01

    An alkaline lipase from Trichosporon asahii MSR 54 was used to develop presoak formulation for removing oil stains at ambient temperature. The lipase was produced in a reactor followed by concentration by ultrafiltration and then it was dried with starch. The biochemical characteristics of enzyme showed that it was an alkaline lipase having pH activity in the range of pH 8.0-10.0 and temperature in the range of 25-50 degrees C. The present lipase was active >80% at 25 degrees C. The lipase was cystein activated with fourfold enhancement in presence of 5 mM cystein and likewise the activity was also stimulated in presence of papain hydrolysate which served as source of cystein. The presoak formulation consisted of two components A and B, component A was enzyme additive and B was a mixture of carbonate/bicarbonate source of alkali and papain hydrolysate as source of cystein. The results indicated that the presoaking in enzyme formulation followed by detergent washing was a better strategy for stain removal than direct washing with detergent in presence of lipase. Further, it was observed that 0.25% presoak component B in presence of 100 U enzyme component A (0.1 g) was the best formulation in removing maximum stain from mustard oil/triolein soiled clothes as indicated by increase in reflectance which was found equal to that of control cloth. The lipase action in presoaked formulation was clearly indicated by quantitated fatty acid release and also the TLC results of wash water, where oil hydrolytic products were visible only in presence of enzyme in the treatment. The wash performance carried at 25 degrees C indicated that washing at 25 degrees C was at par with that at 40 degrees C as indicated by similar reflectance of the washed cloth piece though qualitative fatty acid release was higher at 40 degrees C.

  13. A practical synthesis of sarpogrelate hydrochloride and in vitro platelet aggregation inhibitory activities of its analogues

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A convenient approach for the preparation of sarpogrelate hydrochloride was developed.Two series of sarpogrelate hydrochloride analogues were designed and synthesized in order to improve their platelet aggregation inhibitory activities, biological tests suggested that these compounds have platelet aggregation inhibitory activities to some extent.

  14. Hydrolysis of guinea pig nascent very low density lipoproteins catalyzed by lipoprotein lipase: activation by hjman apolipoprotein C-II.

    Science.gov (United States)

    Fitzharris, T J; Quinn, D M; Goh, E H; Johnson, J D; Kashyap, M L; Srivastava, L S; Jackson, R L; Harmony, J A

    1981-08-01

    Very low density lipoproteins isolated from guinea pig liver perfusate (VLDLp) lack the equivalent of human apolipoprotein C-II (apoC-II), the activator of lipoprotein lipase (LpL). These lipoproteins are therefore ideal substrates with which to investigate the mechanism by which apoC-II activates the enzyme. VLDLp binds apoC-II, and apoC-II associated with VLDLp markedly increases the rate of lipoprotein lipase-catalyzed hydrolysis of VLDLp-triglycerides. The activator potency of apoC-II is independent of the method of enrichment of VLDLp with apoC-II: delipidated human apoC-II and apoC-II transferred from human high density lipoproteins activate lipoprotein lipase to equal extents. ApoC-II causes pH-dependent changes in both apparent Km and VmaX of LpL-catalyzed hydrolysis of VLDLp-triglycerides. At pH l7.4--7.5, the major effects of apoC-II is to decrease the apparent Km by 3.3--4.0 fold. The apparent Vmax is increased 1.3-fold. At pH 6.5 and 8.5, the decrease of apparent Km is less marked, 1.6-fold and 1.4-fold, respectively. At pH 6.5, apoC-II increases the apparent Vmax ty 1.3-fold, while at pH 8.5 the primary effect of apoC-II is a 1.6-fold increase of apparent Vmax. Based on a simple kinetic model, the data suggest that apoC-II favors direct interaction between enzyme and triglyceride within the lipoprotein particle, as well as subsequent catalytic turnover.

  15. Zinc deficiency and the activities of lipoprotein lipase in plasma and tissues of rats force-fed diets with coconut oil or fish oil.

    Science.gov (United States)

    Kettler, S I; Eder, K; Kettler, A; Kirchgessner, M

    2000-03-01

    The present study was performed to investigate the effect of zinc deficiency on the activities of lipoprotein lipase in postheparin serum and tissues of rats fed diets containing either coconut oil or fish oil as dietary fat, using a bifactorial experimental design. To ensure an adequate food intake, all the rats were force-fed by gastric tube. Experimental diets contained either 0.8 mg zinc/kg (zinc-deficient diets) or 40 mg zinc/kg (zinc-adequate diets). The effects of zinc deficiency on the activities of lipoprotein lipase in postheparin serum and postprandial triglyceride concentrations and distribution of apolipoproteins in serum lipoproteins depended on the type of dietary fat. Zinc-deficient rats fed the coconut oil diet exhibited a reduced activity of lipoprotein lipase in postheparin serum and adipose tissue, markedly increased concentrations of triglycerides in serum, and a markedly reduced content of apolipoprotein C in triglyceride-rich lipoproteins and high density lipoproteins compared with zinc-adequate rats fed coconut oil. By contrast, zinc-deficient rats fed the fish oil diet did not exhibit reduced activities of lipoprotein lipase in postheparin serum and adipose tissue and increased concentrations of serum lipids compared with zinc-adequate rats fed the fish oil diet. This study suggests that a reduced activity of lipoprotein lipase might contribute to increased postprandial concentrations of serum triglycerides observed in zinc-deficient animals. However, it also demonstrates that the effects of zinc deficiency on lipoprotein metabolism are influenced by dietary fatty acids.

  16. Microwave-assisted synthesis and tyrosinase inhibitory activity of chalcone derivatives.

    Science.gov (United States)

    Liu, Jinbing; Chen, Changhong; Wu, Fengyan; Zhao, Liangzhong

    2013-07-01

    A series of chalcones and their derivatives were synthesized, and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that some of the synthesized compounds exhibited significant inhibitory activity, and four compounds exhibited more potent tyrosinase inhibitory activity than the reference standard inhibitor kojic acid (5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one). Specifically, 1-(-1-(4-methoxyphen- yl)-3-phenylallylidene)thiosemicarbazide (18) exhibited the most potent tyrosinase inhibitory activity with IC₅₀ value of 0.274 μM. The inhibition mechanism analysis of 1-(-1-(2,4-dihydroxyphenyl)-3-phenylallylidene) thiosemicarbazide (16) and 1-(-1-(4-methoxyphenyl)-3-phenylallylidene) thiosemicarbazide (18) demonstrated that the inhibitory effects of the two compounds on the tyrosinase were irreversible. Preliminary structure activity relationships' analysis suggested that further development of such compounds might be of interest.

  17. Study of Molecular Conformation and Activity-Related Properties of Lipase Immobilized onto Core-Shell Structured Polyacrylic Acid-Coated Magnetic Silica Nanocomposite Particles.

    Science.gov (United States)

    Esmaeilnejad-Ahranjani, Parvaneh; Kazemeini, Mohammad; Singh, Gurvinder; Arpanaei, Ayyoob

    2016-04-01

    A facile approach for the preparation of core-shell structured poly(acrylic acid) (PAA)-coated Fe3O4 cluster@SiO2 nanocomposite particles as the support materials for the lipase immobilization is reported. Low- or high-molecular-weight (1800 and 100,000, respectively) PAA molecules were covalently attached onto the surface of amine-functionalized magnetic silica nanoacomposite particles. The successful preparation of particles were verified by scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential measurement, and Fourier-transform infrared (FTIR) techniques. Once lipase is covalently immobilized onto the particles with an average diameter of 210 ± 50 nm, resulting from high binding sites concentrations on the low- and high-molecular-weight PAA-coated particles, high lipase immobilization efficiencies (86.2% and 89.9%, respectively), and loading capacities (786 and 816 mg g(-1), respectively) are obtained. Results from circular dichroism (CD) analysis and catalytic activity tests reveal an increase in the β-sheet content of lipase molecules upon immobilization, along with an enhancement in their activities and stabilities. The lipases immobilized onto the low- and high-molecular-weight PAA-coated particles show maximum activities at 55 and 50 °C, respectively, which are ∼28% and ∼15% higher than that of the free lipase at its own optimum temperature (40 °C), respectively. The immobilized lipases exhibit excellent performance at broader temperature and pH ranges and high thermal and storage stabilities, as well as superior reusability. These prepared magnetic nanocomposite particles can be offered as suitable support materials for efficient immobilization of enzymes and improvement of the immobilized enzymes properties.

  18. Hormone-sensitive lipase, the rate-limiting enzyme in triglyceride hydrolysis, is expressed and active in beta-cells.

    Science.gov (United States)

    Mulder, H; Holst, L S; Svensson, H; Degerman, E; Sundler, F; Ahrén, B; Rorsman, P; Holm, C

    1999-01-01

    Triglycerides in the beta-cell may be important for stimulus-secretion coupling, through provision of a lipid-derived signal, and for pathogenetic events in NIDDM, where lipids may adversely affect beta-cell function. In adipose tissues, hormone-sensitive lipase (HSL) is rate-limiting in triglyceride hydrolysis. Here, we investigated whether this enzyme is also expressed and active in beta-cells. Northern blot analysis and reverse transcription-polymerase chain reaction demonstrated that HSL is expressed in rat islets and in the clonal beta-cell lines INS-1, RINm5F, and HIT-T15. Western blot analysis identified HSL in mouse and rat islets and the clonal beta-cells. In mouse and rat, immunocytochemistry showed a predominant occurrence of HSL in beta-cells, with a presumed cytoplasmic localization. Lipase activity in homogenates of the rodent islets and clonal beta-cells constituted 2.1 +/- 0.6% of that in adipocytes; this activity was immunoinhibited by use of antibodies to HSL. The established HSL expression and activity in beta-cells offer a mechanism whereby lipids are mobilized from intracellular stores. Because HSL in adipocytes is activated by cAMP-dependent protein kinase (PKA), PKA-regulated triglyceride hydrolysis in beta-cells may participate in the regulation of insulin secretion, possibly by providing a lipid-derived signal, e.g., long-chain acyl-CoA and diacylglycerol.

  19. Lipoprotein particle distribution and skeletal muscle lipoprotein lipase activity after acute exercise

    Directory of Open Access Journals (Sweden)

    Harrison Michael

    2012-07-01

    Full Text Available Abstract Background Many of the metabolic effects of exercise are due to the most recent exercise session. With recent advances in nuclear magnetic resonance spectroscopy (NMRS, it is possible to gain insight about which lipoprotein particles are responsible for mediating exercise effects. Methods Using a randomized cross-over design, very low density lipoprotein (VLDL responses were evaluated in eight men on the morning after i an inactive control trial (CON, ii exercising vigorously on the prior evening for 100 min followed by fasting overnight to maintain an energy and carbohydrate deficit (EX-DEF, and iii after the same exercise session followed by carbohydrate intake to restore muscle glycogen and carbohydrate balance (EX-BAL. Results The intermediate, low and high density lipoprotein particle concentrations did not differ between trials. Fasting triglyceride (TG determined biochemically, and mean VLDL size were lower in EX-DEF but not in EX-BAL compared to CON, primarily due to a reduction in VLDL-TG in the 70–120 nm (large particle range. In contrast, VLDL-TG was lower in both EX-DEF and EX-BAL compared to CON in the 43–55 nm (medium particle range. VLDL-TG in smaller particles (29–43 nm was unaffected by exercise. Because the majority of VLDL particles were in this smallest size range and resistant to change, total VLDL particle concentration was not different between any of these conditions. Skeletal muscle lipoprotein lipase (LPL activity was also not different across these 3 trials. However, in CON only, the inter-individual differences in LPL activity were inversely correlated with fasting TG, VLDL-TG, total, large and small VLDL particle concentration and VLDL size, indicating a regulatory role for LPL in the non-exercised state. Conclusions These findings reveal a high level of differential regulation between different sized triglyceride-rich lipoproteins following exercise and feeding, in the absence of changes in

  20. Lipoprotein particle distribution and skeletal muscle lipoprotein lipase activity after acute exercise

    LENUS (Irish Health Repository)

    Harrison, Michael

    2012-06-06

    AbstractBackgroundMany of the metabolic effects of exercise are due to the most recent exercise session. With recent advances in nuclear magnetic resonance spectroscopy (NMRS), it is possible to gain insight about which lipoprotein particles are responsible for mediating exercise effects.MethodsUsing a randomized cross-over design, very low density lipoprotein (VLDL) responses were evaluated in eight men on the morning after i) an inactive control trial (CON), ii) exercising vigorously on the prior evening for 100 min followed by fasting overnight to maintain an energy and carbohydrate deficit (EX-DEF), and iii) after the same exercise session followed by carbohydrate intake to restore muscle glycogen and carbohydrate balance (EX-BAL).ResultsThe intermediate, low and high density lipoprotein particle concentrations did not differ between trials. Fasting triglyceride (TG) determined biochemically, and mean VLDL size were lower in EX-DEF but not in EX-BAL compared to CON, primarily due to a reduction in VLDL-TG in the 70–120 nm (large) particle range. In contrast, VLDL-TG was lower in both EX-DEF and EX-BAL compared to CON in the 43–55 nm (medium) particle range. VLDL-TG in smaller particles (29–43 nm) was unaffected by exercise. Because the majority of VLDL particles were in this smallest size range and resistant to change, total VLDL particle concentration was not different between any of these conditions. Skeletal muscle lipoprotein lipase (LPL) activity was also not different across these 3 trials. However, in CON only, the inter-individual differences in LPL activity were inversely correlated with fasting TG, VLDL-TG, total, large and small VLDL particle concentration and VLDL size, indicating a regulatory role for LPL in the non-exercised state.ConclusionsThese findings reveal a high level of differential regulation between different sized triglyceride-rich lipoproteins following exercise and feeding, in the absence of changes in LPL activity.

  1. Antioxidant Activity and α-Glucosidase Inhibitory Activities of the Polycondensate of Catechin with Glyoxylic Acid.

    Directory of Open Access Journals (Sweden)

    Sheng Geng

    Full Text Available In order to investigate polymeric flavonoids, the polycondensate of catechin with glyoxylic acid (PCG was prepared and its chemically antioxidant, cellular antioxidant (CAA and α-glucosidase inhibitory activities were evaluated. The DPPH and ABTS radical scavenging activities and antiproliferative effect of PCG were lower than those of catechin, while PCG had higher CAA activity than catechin. In addition, PCG had very high α-glucosidase inhibitory activities (IC50 value, 2.59 μg/mL in comparison to catechin (IC50 value, 239.27 μg/mL. Inhibition kinetics suggested that both PCG and catechin demonstrated a mixture of noncompetitive and anticompetitive inhibition. The enhanced CAA and α-glucosidase inhibitor activities of PCG could be due to catechin polymerization enhancing the binding capacity to the cellular membrane and enzymes.

  2. Lipase Test

    Science.gov (United States)

    ... with pancreatic duct obstruction, pancreatic cancer , and other pancreatic diseases as well as with gallbladder inflammation or kidney ... damage to the lipase-producing cells in the pancreas. This can occur in chronic diseases that affect the pancreas such as cystic fibrosis . ^ ...

  3. Covalent immobilization of porcine pancreatic lipase on carboxyl-activated magnetic nanoparticles: Characterization and application for enzymatic inhibition assays

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yuan-Ting [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Ren, Xiao-Yun [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Liu, Yi-Ming [Department of Chemistry and Biochemistry, Jackson State University, 1400 Lynch St., Jackson, MS 39217 (United States); Wei, Ying [Changzhi Medical College, Changzhi 046000 (China); Qing, Lin-Sen [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China); Liao, Xun, E-mail: liaoxun@cib.ac.cn [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 (China)

    2014-05-01

    Using carboxyl functionalized silica-coated magnetic nanoparticles (MNPs) as carrier, a novel immobilized porcine pancreatic lipase (PPL) was prepared through the 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) coupling reaction. Transmission electron microscopic images showed that the synthesized nanoparticles (Fe{sub 3}O{sub 4}–SiO{sub 2}) possessed three dimensional core–shell structures with an average diameter of ∼ 20 nm. The effective enzyme immobilization onto the nanocomposite was confirmed by atomic force microscopic (AFM) analysis. Results from Fourier-transform infrared spectroscopy (FT-IR), Bradford protein assay, and thermo-gravimetric analysis (TGA) indicated that PPL was covalently attached to the surface of magnetic nanoparticles with a PPL immobilization yield of 50 mg enzyme/g MNPs. Vibrating sample magnetometer (VSM) analysis revealed that the MNPs-PPL nanocomposite had a high saturation magnetization of 42.25 emu·g{sup −1}. The properties of the immobilized PPL were investigated in comparison with the free enzyme counterpart. Enzymatic activity, reusability, thermo-stability, and storage stability of the immobilized PPL were found significantly superior to those of the free one. The K{sub m} and the V{sub max} values (0.02 mM, 6.40 U·mg{sup −1} enzyme) indicated the enhanced activity of the immobilized PPL compared to those of the free enzyme (0.29 mM, 3.16 U·mg{sup −1} enzyme). Furthermore, at an elevated temperature of 70 °C, immobilized PPL retained 60% of its initial activity. The PPL-MNPs nanocomposite was applied in the enzyme inhibition assays using orlistat, and two natural products isolated from oolong tea (i.e., EGCG and EGC) as the test compounds. - Highlights: • Porcine pancreatic lipase was firstly covalently immobilized onto carboxylated MNPs. • Immobilized porcine pancreatic lipase (PPL) was characterized by various techniques. • MNPs-PPL showed higher activity

  4. Optimization of biomass production of a mutant of Yarrowia lipolytica with an increased lipase activity using raw glycerol

    Directory of Open Access Journals (Sweden)

    Miguel A Galvagno

    2011-09-01

    Full Text Available The yeast Yarrowia lipolytica accumulates oils and is able to produce extracellular lipases when growing in different carbon sources including glycerol, the principal by-product of the biodiesel industry. In this study, biomass production of a novel mutant strain of Y. lipolytica was statistically optimized by Response Surface Methodology in media containing biodiesel-derived glycerol as main carbon source. This strain exhibited distinctive morphological and fatty acid profile characteristics, and showed an increased extracellular lipase activity. An organic source of nitrogen and the addition of 1.0 g/l olive oil were necessary for significant lipase production. Plackett-Burman and Central Composite Statistical Designs were employed for screening and optimization of fermentation in shaken flasks cultures, and the maximum values obtained were 16.1 g/l for biomass and 12.2 Units/ml for lipase, respectively. Optimized batch bioprocess was thereafter scaled in aerated bioreactors and the values reached for lipase specific activity after 95 % of the glycerol had been consumed, were three-fold higher than those obtained in shaken flasks cultures. A sustainable bioprocess to obtain biomass and extracellular lipase activity was attained by maximizing the use of the by-products of biodiesel industry.Optimización de la producción de biomasa usando glicerol crudo, de una cepa mutante de Yarrowia lipolytica con actividad incrementada de lipasa. La levadura Yarrowia lipolytica acumula aceites y produce una lipasa extracelular al crecer en diferentes fuentes de carbono, entre ellas el glicerol, principal subproducto de la creciente industria del biodiésel. En el presente trabajo, se optimizó mediante la metodología de superficies de respuesta la producción de biomasa de una nueva cepa mutante de Y. lipolytica, empleando medios con glicerol derivado de la industria del biodiésel como principal fuente de carbono. Esta cepa presentó caracter

  5. Convergence of inhibitory neural inputs regulate motor activity in the murine and monkey stomach.

    Science.gov (United States)

    Shaylor, Lara A; Hwang, Sung Jin; Sanders, Kenton M; Ward, Sean M

    2016-11-01

    Inhibitory motor neurons regulate several gastric motility patterns including receptive relaxation, gastric peristaltic motor patterns, and pyloric sphincter opening. Nitric oxide (NO) and purines have been identified as likely candidates that mediate inhibitory neural responses. However, the contribution from each neurotransmitter has received little attention in the distal stomach. The aims of this study were to identify the roles played by NO and purines in inhibitory motor responses in the antrums of mice and monkeys. By using wild-type mice and mutants with genetically deleted neural nitric oxide synthase (Nos1(-/-)) and P2Y1 receptors (P2ry1(-/-)) we examined the roles of NO and purines in postjunctional inhibitory responses in the distal stomach and compared these responses to those in primate stomach. Activation of inhibitory motor nerves using electrical field stimulation (EFS) produced frequency-dependent inhibitory junction potentials (IJPs) that produced muscle relaxations in both species. Stimulation of inhibitory nerves during slow waves terminated pacemaker events and associated contractions. In Nos1(-/-) mice IJPs and relaxations persisted whereas in P2ry1(-/-) mice IJPs were absent but relaxations persisted. In the gastric antrum of the non-human primate model Macaca fascicularis, similar NO and purine neural components contributed to inhibition of gastric motor activity. These data support a role of convergent inhibitory neural responses in the regulation of gastric motor activity across diverse species.

  6. Interactions of dietary fat intake and the hepatic kipase -480C-->T polymorphism in determining hepatic lipase activity: the Hoorn Study

    NARCIS (Netherlands)

    Bos, Griët; Dekker, J.M.; Feskens, E.J.M.; Ocke, M.C.; Nijpels, Giel

    2005-01-01

    Background: Gene-nutrient interactions affecting hepatic lipase (HL) activity may contribute to the interindividual variability of the cardiovascular disease risk associated with dietary fat intake. Objective: We determined the associations of dietary fat intake with postheparin HL activity and the

  7. Cloning and characterization of newly isolated lipase from Enterobacter sp. Bn12.

    Science.gov (United States)

    Farrokh, Parisa; Yakhchali, Bagher; Karkhane, Ali Asghar

    2014-01-01

    A mesophilic Enterobacter sp. Bn12 producing an alkaline thermostable lipase was isolated from soil in Tehran, Iran. The lipase gene (ELBn12) was identified from a genomic library. Sequence analysis of the DNA fragment revealed an open reading frame of 879 bp encoding a lipase with a molecular mass of 31.3 kDa. The deduced amino acid sequence showed 96% identity with a lipase of Enterobacter sp. Ag1 and the identity of their DNA sequences was 88.9%. ELBn12 belongs to the lipase subfamily I.1 and its catalytic triad consists of Ser82, Asp237 and His259. The lipase was expressed in Escherichia coli (BL21) pLysS and partially purified by anion exchange chromatography. The maximum activity of ELBn12 was obtained at temperature of 60 °C and pH 8.0 towards tricaprylin (C8) and its specific activity was around 2900 U/mg. ELBn12 was stable within a broad pH range from 6.0 to 11.0. The enzyme showed high stability in both polar and nonpolar organic solvents at 50% (v/v). The lipase activity was enhanced in the presence of 10 mM of Ca(2+), Mg(2+) and K(+), while heavy metals (Fe(3+) and Zn(2+)) had strong inhibitory effect. ELBn12 showed high activity in the presence of 1% (w/v) nonionic surfactants, however ionic surfactants inhibited the lipolytic activity. ELBn12 characteristics show that it has a potential to be used in various industrial processes.

  8. Testosterone 5alpha-reductase inhibitory active constituents of Piper nigrum leaf.

    Science.gov (United States)

    Hirata, Noriko; Tokunaga, Masashi; Naruto, Shunsuke; Iinuma, Munekazu; Matsuda, Hideaki

    2007-12-01

    Previously we reported that Piper nigrum leaf extract showed a potent stimulation effect on melanogenesis and that (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2) were isolated as active constituents. As a part of our continuous studies on Piper species for the development of cosmetic hair-care agents, testosterone 5alpha-reductase inhibitory activity of aqueous ethanolic extracts obtained from several different parts of six Piper species, namely Piper nigrum, P. methysticum, P. betle, P. kadsura, P. longum, and P. cubeba, were examined. Among them, the extracts of P. nigrum leaf, P. nigrum fruit and P. cubeba fruit showed potent inhibitory activity. Activity-guided fractionation of P. nigrum leaf extract led to the isolation of 1 and 2. Fruits of P. cubeba contain 1 as a major lignan, thus inhibitory activity of the fruit may be attributable to 1. As a result of further assay on other known constituents of the cited Piper species, it was found that piperine, a major alkaloid amide of P. nigrum fruit, showed potent inhibitory activity, thus a part of the inhibitory activity of P. nigrum fruit may depend on piperine. The 5alpha-reductase inhibitory activities of 1 and piperine were found for the first time. In addition, the P. nigrum leaf extract showed in vivo anti-androgenic activity using the hair regrowth assay in testosterone sensitive male C57Black/6CrSlc strain mice.

  9. Lipase Improvement: Goals and strategies

    OpenAIRE

    Bassegoda, Arnau; Cesarini, Silvia; Diaz, Pilar

    2012-01-01

    Lipases have received great attention as industrial biocatalysts in areas like oils and fats processing, detergents, baking, cheese making, surface cleaning, or fine chemistry . They can catalyse reactions of insoluble substrates at the lipid-water interface, preserving their catalytic activity in organic solvents. This makes of lipases powerful tools for catalysing not only hydrolysis, but also various reverse reactions such as esterification, transesterification, aminolysis, or thiotransest...

  10. Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

    Directory of Open Access Journals (Sweden)

    García-Arias Carlota

    2009-06-01

    Full Text Available Abstract Background Severe hypertriglyceridaemia due to chylomicronemia may trigger an acute pancreatitis. However, the basic underlying mechanism is usually not well understood. We decided to analyze some proteins involved in the catabolism of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia. Methods Twenty-four survivors of acute hypertriglyceridaemic pancreatitis (cases and 31 patients with severe hypertriglyceridaemia (controls were included. Clinical and anthropometrical data, chylomicronaemia, lipoprotein profile, postheparin lipoprotein lipase mass and activity, hepatic lipase activity, apolipoprotein C II and CIII mass, apo E and A5 polymorphisms were assessed. Results Only five cases were found to have LPL mass and activity deficiency, all of them thin and having the first episode in childhood. No cases had apolipoprotein CII deficiency. No significant differences were found between the non-deficient LPL cases and the controls in terms of obesity, diabetes, alcohol consumption, drug therapy, gender distribution, evidence of fasting chylomicronaemia, lipid levels, LPL activity and mass, hepatic lipase activity, CII and CIII mass or apo E polymorphisms. However, the SNP S19W of apo A5 tended to be more prevalent in cases than controls (40% vs. 23%, NS. Conclusion Primary defects in LPL and C-II are rare in survivors of acute hypertriglyceridaemic pancreatitis; lipase activity measurements should be restricted to those having their first episode during chilhood.

  11. Polysaccharide with antioxidant, α-amylase inhibitory and ACE inhibitory activities from Momordica charantia.

    Science.gov (United States)

    Tan, Hwee-Feng; Gan, Chee-Yuen

    2016-04-01

    Functional polysaccharide was isolated from Momordica charantia, with a yield of 36% (w/w). M. charantia bioactive polysaccharide (MCBP) was an acidic and branched heteropolysaccharide with a molecular weight of 92 kDa. Fourier transform infrared spectroscopic analysis indicated that MCBP was a pectin-like polysaccharide with an esterification degree of 53% and it contains numerous monosaccharides, predominantly glucose, galactose, and galaturonic acid. The results also showed that MCBP exhibited free radical scavenging activity (31.9%), ferric reducing antioxidant power (0.95 mM), α-amylase inhibition (89.1%), and angiotensin-converting enzyme inhibition (94.1%). In the terms of functionality, MCBP showed a lower water-holding capacity but higher in oil-holding capacity, emulsifying activity and foaming capacity compared to citrus pectin. Scanning electron microscopy images demonstrated that MCBP formed gels with a porous structure, and flow analysis showed that the gel solution exhibited pseudoplastic shear-thinning behavior. These findings indicated that MCBP is a promising functional macromolecular carbohydrate for the food and nutraceutical industries. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Preparation of Layered Double Hydroxide-Immobilized Lipase for High Yield and Optically Active (-)-Menthyl butyrate

    Institute of Scientific and Technical Information of China (English)

    Siti; Salhah; Othman; Mahiran; Basri; Mohd.Zobir; Hussein; Mohd; Basyaruddin; Abdul; Rahman; Raja; Noor; Zaliha; Raja; Abdul; Rahman; Abu; Bakar; Salleh; Salina; Mat; Radzi; Azwani; Sofia; Ahmad; Khiar

    2007-01-01

    1 Results Layered Double Hydroxide (LDH) finds extensive usage in the areas of pharmaceutical sciences and catalysis. In this study, a member of the LDH family, Mg/Al-hydrotalcite (HT), or the so-called anionic clay, was prepared at ratio 4 (HT) by co-precipitating through continuous agitation. X-ray diffraction pattern and thermogravimetric analysis of the material indicated that a pure HT had been successfully synthesized. This matrix was then used as support in the immobilization of lipase from Cand...

  13. Correlations between the lipophilicity and the inhibitory activity of different substituted benzimidazoles

    Directory of Open Access Journals (Sweden)

    DIJANA J. BARNA

    2009-09-01

    Full Text Available 2-Amino and 2-methylbenzimidazole derivatives were tested in vitro for their inhibitory activity against the bacteria Bacillus cereus. The minimum inhibitory concentration (MIC was determined for all compounds. The lipophilicity descriptors were calculated by using CS Chem-Office Software, version 7.0. The stepwise regression method was used to derive the most significant model as a calibration model for predicting the antibacterial activity of this class of compounds. A complete regression analysis resorting to linear and quadratic relationships was made. Theoretical models were validated by leaving one out (LOO technique, as well as by the calculation of statistical parameters for the established models. The best QSAR model for the prediction of an inhibitory activity of the investigated series of benzimidazoles was developed. A high agreement between the experimental and predicted inhibitory values was obtained. The results indicated that the antibacterial activity could be modeled using the lipophilicity descriptor.

  14. Elucidation of a key position for acyltransfer activity in Candida parapsilosis lipase/acyltransferase (CpLIP2) and in Pseudozyma antarctica lipase A (CAL-A) by rational design.

    Science.gov (United States)

    Jan, Anne-Hélène; Subileau, Maeva; Deyrieux, Charlotte; Perrier, Véronique; Dubreucq, Éric

    2016-02-01

    Performing transesterifications in aqueous media is becoming a priority challenge in lipid biotechnology in order to develop more eco-friendly and efficient biocatalytic processes in systems containing both polar and apolar substrates. In this context, our group has explored for several years the high potential of the lipase/acyltransferase CpLIP2 from Candida parapsilosis and of several of its homologs, that catalyze efficiently acyltransfer reactions in lipid/water media with high water activity (aw>0.9). The discovery of a new member of this group, CduLAc from Candida dubliniensis, with a higher acyltransferase activity than CpLIP2, has provided a new insight on structure-function relationships in this group. Indeed, the comparison of sequences and 3D models, especially of CpLIP2 and CduLAc, with those of the phylogenetically related lipase A from Pseudozyma antarctica (CAL-A), allowed elucidating a key structural determinant of the acyltransferase activity: serine S369 in CpLIP2 and its equivalents E370 in CAL-A and A366 in CduLAc. Mutants obtained by rational design at this key position showed significant changes in acyltransfer activity. Whereas mutation S369E resulted in an increase in the hydrolytic activity of CpLIP2, S369A increased alcoholysis. More strikingly, the single E370A mutation in CAL-A drastically increased the acyltransferase activity of this enzyme, giving it the character of a lipase/acyltransferase. Indeed, this single mutation lowered the methanol concentration for which the initial rates of alcoholysis and hydrolysis are equal from 2M in CAL-A down to 0.3M in its mutant, while the exceptional stability of the parental enzyme toward alcohol and temperature was conserved.

  15. Lipase-catalysed ester synthesis in solvent-free oil system: is it esterification or transesterification?

    Science.gov (United States)

    Sun, Jingcan; Yu, Bin; Curran, Philip; Liu, Shao-Quan

    2013-12-01

    Ester synthesis was carried out in a solvent-free system of lipase, coconut oil and ethanol or fusel alcohols to ascertain the reaction mechanism. During ester formation, octanoic and decanoic acids increased initially and then decreased gradually, indicating that ester production was a two-step reaction consisting of hydrolysis and esterification, rather than alcoholysis. With ethanol as the alcohol substrate, added butyric acid inhibited ester synthesis. However, when fusel alcohols were used as the alcohol substrate, no significant inhibitory effect by butyric acid was observed. Added octanoic acid did not show any adverse effect on the synthesis of corresponding esters. The results suggest that polarity of the reactants determines lipase activity. This study provides the first evidence on the mechanism of immobilised lipase-catalysed ester synthesis in a solvent-free system involving both hydrolysis and esterification.

  16. Synthesis and VEGF inhibitory activity of 16,17-pyrazo-annulated steroids

    Institute of Scientific and Technical Information of China (English)

    Hong Shan Liu; Hu Ling Zheng; Mei Ge; Peng Xia; Ying Chen

    2011-01-01

    Eight 16,17-pyrazo-annulated steroidal derivatives were synthesized and evaluated in vitro vascular endothelial growth factor (VEGF) inhibitory activity with 2-methoxyestradiol (2-ME) as the reference compound. Most of the compounds showed potent VEGF inhibitory activity with EC50 values of micromolar or submicromolar range. Among them, the compounds 3 and 8 exhibited similar EC50 values and obviously better TI values compared with 2-ME.

  17. Relative effectiveness of pretreatments on performance of Rhizomucor miehei lipase in nonpolar reaction media.

    Science.gov (United States)

    Garcia, Rafael A; Riley, Mark R

    2005-02-01

    Enzymes can be used in nonpolar reaction media to modify water-insoluble substrates. A variety of pretreatments, applied to the enzyme prior to introduction to the nonpolar media, can improve enzyme activity. However, the various pretreatments have not been studied using directly comparable conditions, nor have they been applied simultaneously to test for interactive effects. This work evaluates pretreatment of lipase with various classes of additives. The pretreated lipase is used to catalyze esterification between citronellol and acetic acid in a medium of n-hexane. The effectiveness of a particular pretreatment is presented in terms of relative performance (RP), which is equal to the number of times faster the pretreated lipase catalyzes the reaction relative to untreated lipase. The individual and interactive effects of the pretreatment factors were studied and compared. Buffer salts had a much stronger performance-enhancing effect than nonbuffer salts; pretreatment with 90% (w/w) sodium phosphate yielded lipase with an RP of approx 64. A strong interaction was found between the treatments with sodium phosphate and pH adjustment. These treatments may mitigate the inhibitory effect of acetic acid. Activating effects of phase interfaces and active-site protectants are shown to be complementary to other treatments, demonstrating that they likely act by distinct mechanisms.

  18. Remodeling and Tenacity of Inhibitory Synapses: Relationships with Network Activity and Neighboring Excitatory Synapses.

    Science.gov (United States)

    Rubinski, Anna; Ziv, Noam E

    2015-11-01

    Glutamatergic synapse size remodeling is governed not only by specific activity forms but also by apparently stochastic processes with well-defined statistics. These spontaneous remodeling processes can give rise to skewed and stable synaptic size distributions, underlie scaling of these distributions and drive changes in glutamatergic synapse size "configurations". Where inhibitory synapses are concerned, however, little is known on spontaneous remodeling dynamics, their statistics, their activity dependence or their long-term consequences. Here we followed individual inhibitory synapses for days, and analyzed their size remodeling dynamics within the statistical framework previously developed for glutamatergic synapses. Similar to glutamatergic synapses, size distributions of inhibitory synapses were skewed and stable; at the same time, however, sizes of individual synapses changed considerably, leading to gradual changes in synaptic size configurations. The suppression of network activity only transiently affected spontaneous remodeling dynamics, did not affect synaptic size configuration change rates and was not followed by the scaling of inhibitory synapse size distributions. Comparisons with glutamatergic synapses within the same dendrites revealed a degree of coupling between nearby inhibitory and excitatory synapse remodeling, but also revealed that inhibitory synapse size configurations changed at considerably slower rates than those of their glutamatergic neighbors. These findings point to quantitative differences in spontaneous remodeling dynamics of inhibitory and excitatory synapses but also reveal deep qualitative similarities in the processes that control their sizes and govern their remodeling dynamics.

  19. Interaction between the triglyceride lipase ATGL and the arf1 activator GBF1

    KAUST Repository

    Ellong, Emy Njoh

    2011-07-18

    The Arf1 exchange factor GBF1 (Golgi Brefeldin A resistance factor 1) and its effector COPI are required for delivery of ATGL (adipose triglyceride lipase) to lipid droplets (LDs). Using yeast two hybrid, co-immunoprecipitation in mammalian cells and direct protein binding approaches, we report here that GBF1 and ATGL interact directly and in cells, through multiple contact sites on each protein. The C-terminal region of ATGL interacts with N-terminal domains of GBF1, including the catalytic Sec7 domain, but not with full-length GBF1 or its entire N-terminus. The N-terminal lipase domain of ATGL (called the patatin domain) interacts with two C-terminal domains of GBF1, HDS (Homology downstream of Sec7) 1 and HDS2. These two domains of GBF1 localize to lipid droplets when expressed alone in cells, but not to the Golgi, unlike the full-length GBF1 protein, which localizes to both. We suggest that interaction of GBF1 with ATGL may be involved in the membrane trafficking pathway mediated by GBF1, Arf1 and COPI that contributes to the localization of ATGL to lipid droplets.

  20. New eutectic ionic liquids for lipase activation and enzymatic preparation of biodiesel.

    Science.gov (United States)

    Zhao, Hua; Baker, Gary A; Holmes, Shaletha

    2011-03-21

    The enzymatic preparation of biodiesel has been hampered by the lack of suitable solvents with desirable properties such as high lipase compatibility, low cost, low viscosity, high biodegradability, and ease of product separation. Recent interest in using ionic liquids (ILs) as advanced reaction media has led to fast reaction rates and high yields in the enzymatic synthesis of biodiesel. However, conventional (i.e., cation-anion paired) ILs based on imidazolium and other quaternary ammonium salts remain too expensive for wide application at industrial scales. In this study, we report on newly-synthesized eutectic ILs derived from choline acetate or choline chloride coupled with biocompatible hydrogen-bond donors, such as glycerol. These eutectic solvents have favorable properties including low viscosity, high biodegradability, and excellent compatibility with Novozym(®) 435, a commercial immobilized Candida antarctica lipase B. Furthermore, in a model biodiesel synthesis system, we demonstrate high reaction rates for the enzymatic transesterification of Miglyol(®) oil 812 with methanol, catalyzed by Novozym(®) 435 in choline acetate/glycerol (1:1.5 molar ratio). The high conversion (97%) of the triglyceride obtained within 3 h, under optimal conditions, suggests that these novel eutectic solvents warrant further exploration as potential media in the enzymatic production of biodiesel.

  1. Interaction between the triglyceride lipase ATGL and the Arf1 activator GBF1.

    Directory of Open Access Journals (Sweden)

    Emy Njoh Ellong

    Full Text Available The Arf1 exchange factor GBF1 (Golgi Brefeldin A resistance factor 1 and its effector COPI are required for delivery of ATGL (adipose triglyceride lipase to lipid droplets (LDs. Using yeast two hybrid, co-immunoprecipitation in mammalian cells and direct protein binding approaches, we report here that GBF1 and ATGL interact directly and in cells, through multiple contact sites on each protein. The C-terminal region of ATGL interacts with N-terminal domains of GBF1, including the catalytic Sec7 domain, but not with full-length GBF1 or its entire N-terminus. The N-terminal lipase domain of ATGL (called the patatin domain interacts with two C-terminal domains of GBF1, HDS (Homology downstream of Sec7 1 and HDS2. These two domains of GBF1 localize to lipid droplets when expressed alone in cells, but not to the Golgi, unlike the full-length GBF1 protein, which localizes to both. We suggest that interaction of GBF1 with ATGL may be involved in the membrane trafficking pathway mediated by GBF1, Arf1 and COPI that contributes to the localization of ATGL to lipid droplets.

  2. Lipase-catalyzed production of biodiesel fuel from vegetable oils contained in waste activated bleaching earth

    Energy Technology Data Exchange (ETDEWEB)

    Pizarro, Ana V. Lara; Park, Enoch Y. [Shizuoka Univ., Dept. of Applied Biological Chemistry, Shizuoka (Japan)

    2003-02-28

    Waste bleaching earths from crude vegetable oil refining process contain approximately 40% of its weight as oil. Low valued oils are potential substrates for biodiesel fuel production. Vegetable oils from waste bleaching earth samples were organic-solvent extracted and identified as soybean, palm and rapeseed oil. Methanolysis was efficiently catalyzed by Rhizopus oryzae lipase in the presence of high water content, and by a single addition of methanol. R. oryzae lipase was not inactivated by methanol in concentrations lower than 4 milli-equivalents and 75% water content. Optimum conditions for methanolysis of extracted oils were 75% water content (by weight of substrate), an oil/methanol molar ratio of I:4, and 67 IU/g of substrate with agitation at 175 rpm for 96 h at 35 deg C. The highest conversion yield reached 55% (w/w) with palm oil after 96 h of reaction. Adverse viscosity conditions might have influenced methanolysis of extracted soybean and rapeseed oil in spite of high water or methanol concentrations. (Author)

  3. Design of a sialylglycopolymer with a chitosan backbone having efficient inhibitory activity against influenza virus infection.

    Science.gov (United States)

    Umemura, Myco; Itoh, Masae; Makimura, Yutaka; Yamazaki, Kohji; Umekawa, Midori; Masui, Ayano; Matahira, Yoshiharu; Shibata, Mari; Ashida, Hisashi; Yamamoto, Kenji

    2008-08-14

    We verified here the inhibitory activity of a sialylglycopolymer prepared from natural products, chitosan and hen egg yolk, against influenza virus infection and estimated the requirements of the molecule for efficient inhibition. The inhibitory activity clearly depended on two factors, the length (the degree of polymerization: DP) of the chitosan backbone and the amount (the degree of substitution: DS) of conjugated sialyloligosaccharide side chain. The inhibitory efficiency increased in accordance with the DP value, with the highest inhibitory activity obtained when the DP was 1430. The inhibition of virus infection reached more than 90% as the DS value increased up to 15.6% when the neighboring sialyloligosaccharide side chains came as close as 4 nm, which was nearly the distance between two receptor-binding pockets in a hemagglutinin trimer. These results demonstrate that the sialylglycopolymer could be an excellent candidate of the safe and efficient anti-influenza drug.

  4. Acetylcholinesterase-inhibitory activities of the extracts from sponges collected in mauritius waters.

    Science.gov (United States)

    Beedessee, Girish; Ramanjooloo, Avin; Surnam-Boodhun, Rashmee; van Soest, Rob W M; Marie, Daniel E P

    2013-03-01

    Patients diagnosed with Alzheimer's disease (AD) show a characteristic neurochemical deficit of acetylcholine, especially in the basal forebrains. The use of acetylcholinesterase (AChE) inhibitors to retard the hydrolysis of acetylcholine has been suggested as a promising strategy for AD treatment. In this study, we evaluated the acetylcholinesterase inhibitory (AChEI) activities of 134 extracts obtained from 45 species of marine sponges. Thin-layer chromatography (TLC) and microplate assays reveal potent acetylcholinsterase inhibitory activities of two AcOEt extracts from the sponges Pericharax heteroraphis and Amphimedon navalis PULITZER-FINALI. We further investigated the inhibitory kinetics of the extracts and found them to display mixed competitive/noncompetitive inhibition and associated their inhibitory activity partly to terpenoids. Acetylcholinesterase inhibitors from marine organisms have been rarely studied, and this study demonstrated the potential of marine sponges as a source of pharmaceutical leads against neurodegenerative diseases.

  5. Ser649 and Ser650 are the major determinants of protein kinase A-mediated activation of human hormone-sensitive lipase against lipid substrates

    DEFF Research Database (Denmark)

    Krintel, Christian; Osmark, Peter; Larsen, Martin Rask;

    2008-01-01

    Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from stored triacylglycerols. Its activity is regulated by reversible protein phosphorylation. In rat HSL Ser563, Ser659 and Ser660 have been shown to be phosphorylated by protein kinase A (PKA) in vitro as well...

  6. A Correlation between the Activity of Candida antarctica Lipase B and Differences in Binding Free Energies of Organic Solvent and Substrate

    DEFF Research Database (Denmark)

    Banik, Sindrila Dutta; Nordblad, Mathias; Woodley, John

    2016-01-01

    the effect of organic solvent molecules on enzyme structure and the enzymatic reaction on a molecular level. To gain such insight, we combined experimental kinetics studies with full atomic molecular dynamics simulations and found a correlation between the activity of Candida antarctica lipase B (CALB) [for...

  7. Differences in the intramolecular structure of structured oils do not affect pancreatic lipase activity in vitro or the absorption by rats of (n-3) fatty acids.

    Science.gov (United States)

    Porsgaard, Trine; Xu, Xuebing; Göttsche, Jesper; Mu, Huiling

    2005-07-01

    The fatty acid composition and intramolecular structure of dietary triacylglycerols (TAGs) influence their absorption. We compared the in vitro pancreatic lipase activity and the lymphatic transport in rats of fish oil and 2 enzymatically interesterified oils containing 10:0 and (n-3) PUFAs of marine origin to investigate whether the positional distribution of fatty acids influenced the overall bioavailability of (n-3) PUFAs in the body. The structured oils had the (n-3) PUFA either mainly at the sn-1,3 position (LML, M = medium-chain fatty acid, L = long-chain fatty acid) or mainly at the sn-2 position (MLM). Oils were administered to lymph-cannulated rats and lymph was collected for 24 h. The fatty acid composition as well as the lipid class distribution of lymph samples was determined. In vitro pancreatic lipase activity was greater when fish oil was the substrate than when the structured oils were the substrates (P fish oil compared with the 2 structured oils (P lipase activity did not differ. This indicates that the absorption rate is highly influenced by the lipase activity, which in turn is affected by the fatty acid composition and intramolecular structure. The lipid class distribution in lymph collected from the 3 groups of rats did not differ. In conclusion, the intramolecular structure did not affect the overall absorption of (n-3) PUFAs.

  8. Lipoprotein lipase and hepatic triglyceride lipase reduce the infectivity of hepatitis C virus (HCV) through their catalytic activities on HCV-associated lipoproteins.

    Science.gov (United States)

    Shimizu, Yuko; Hishiki, Takayuki; Sugiyama, Kazuo; Ogawa, Kazuya; Funami, Kenji; Kato, Atsushi; Ohsaki, Yuki; Fujimoto, Toyoshi; Takaku, Hiroshi; Shimotohno, Kunitada

    2010-11-10

    The effect of lipolysis by lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) on hepatitis C virus (HCV) infection was evaluated. First, medium from HuH7.5 cells bearing HCV genome replication was treated with LPL. LPL treatment led to reduced HCV infectivity, shifted HCV to higher densities, and lowered the amount of apolipoprotein E-associated HCV. The effect of endogenous HTGL secreted from HuH7.5 on HCV infectivity was next examined. Neutralization of HTGL by an anti-HTGL antibody resulted in suppression of LPL-induced reduction in infectivity of HCV-bearing medium, while knockdown of HTGL by siRNA led to increased HCV infectivity irrespective of LPL. HCV in medium from HTGL knockdown cells was found in fractions with a lower density. These results indicate that changes in the nature of HCV-associated lipoproteins by LPL and/or HTGL affect HCV infectivity, suggesting that association of HCV with specific lipoproteins is important for HCV infectivity. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Comparative studies of canine colipase and lipases from bovine, porcine, canine, human and rat pancreases.

    Science.gov (United States)

    Lee, P C

    1978-01-01

    1. Colipase was purified from canine pancreatic juice and found to have certain specificity in its reaction with various pancreatic lipases. 2. This colipase will stimulate the lipolytic activities of lipases isolated from canine, bovine and porcine pancreas but not lipases from a fungus, or from human and rat pancreases. 3. Characterization of these lipases showed (a) the molecular dimension of rat lipase is very different from the other lipases; (b) the pIs of canine, porcine and bovine lipases are almost identical but different from the pIs of rat, human and Candida (a fungus) lipases; and (c) the antiserum prepared against canine lipase will also react with lipases from human, hog and cow pancreases but not with rat and Candida lipases. 4. These physical differences can explain partly the difference in reaction between the various lipases and the canine colipase.

  10. Analytical importance of determination of lipase activity for the express analysis of contamination by heavy metals of sunflower seeds

    Directory of Open Access Journals (Sweden)

    Y. A. Dyachenko

    2016-01-01

    Full Text Available During the last decades becoming more sharply there is a problem of chemical and environmental monitoring and industrial inspection the content of toxic elements in food raw materials and foodstuff. At the same time there is a need to develop rapid methods, informative, integral, reflecting not only the safety but also the ecological purity of food raw materials. The method of determination of content of toxic elements on activity of its own lipase of in situ (AОL-method in seeds of oil-bearing crops, on the example of sunflower is offered. The system of mathematical assessment of analytical criteria of laboratory test used in clinical laboratory diagnostics was for this purpose adapted. Sunflower seeds in which established the maintenance of toxiferous elements served as an object of a research: Cd, Pb, As, Hg, by atomic absorption method on the KVANT-Z.ETA device. Further tests divided on clear, including high-quality and pollution-free, and polluted - naturally containing toxiferous elements and which are artificially contaminated. Definition of activity of a lipase of seeds was carried out by the standard titrimetric method. Decrease of the activity of enzyme was connected with the maintenance of toxiferous elements. Proceeding from the received results counted an analytical significance (sensitivity, specificity, and predictive value of descriptiveness the positive and negative results of determination of level of maintenance of toxiferous elements in sunflower seeds by the AОL-method. The set values of analytical specificity of a method and predictive value of a positive take at the level of 77.3% and 71.4% respectively, do not allow to use the offered method for the quantitative analysis, however, analytical sensitivity at the level of 86.2% and the predictive value of the negative result at the level of 89.5%, allow to recommend the AOL-method for screening programs of chemical environmental monitoring and technological monitoring of a

  11. Enhancement of lipase activity in non-aqueous media upon immobilization on multi-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Gupta Munishwar N

    2007-11-01

    Full Text Available Abstract Background Immobilization of biologically active proteins on nanosized surfaces is a key process in bionanofabrication. Carbon nanotubes with their high surface areas, as well as useful electronic, thermal and mechanical properties, constitute important building blocks in the fabrication of novel functional materials. Results Lipases from Candida rugosa (CRL were found to be adsorbed on the multiwalled carbon nanotubes with very high retention of their biological activity (97%. The immobilized biocatalyst showed 2.2- and 14-fold increases in the initial rates of transesterification activity in nearly anhydrous hexane and water immiscible ionic liquid [Bmim] [PF6] respectively, as compared to the lyophilized powdered enzyme. It is presumed that the interaction with the hydrophobic surface of the nanotubes resulted in conformational changes leading to the 'open lid' structure of CRL. The immobilized enzyme was found to give 64% conversion over 24 h (as opposed to 14% with free enzyme in the formation of butylbutyrate in nearly anhydrous hexane. Similarly, with ionic liquid [Bmim] [PF6], the immobilized enzyme allowed 71% conversion as compared to 16% with the free enzyme. The immobilized lipase also showed high enantioselectivity as determined by kinetic resolution of (± 1-phenylethanol in [Bmim] [PF6]. While free CRL gave only 5% conversion after 36 h, the immobilized enzyme resulted in 37% conversion with > 99% enantiomeric excess. TEM studies on the immobilized biocatalyst showed that the enzyme is attached to the multiwalled nanotubes. Conclusion Successful immobilization of enzymes on nanosized carriers could pave the way for reduced reactor volumes required for biotransformations, as well as having a use in the construction of miniaturized biosensensor devices.

  12. Determinação das propriedades catalíticas em meio aquoso e orgânico da lipase de Candida rugosa imobilizada em celulignina quimicamente modificada por carbonildiimidazol Assessment of catalytic properties in aqueous and organic media of lipase from Candida rugosa immobilized on wood cellulignin activated with carbonyldiimidazole

    Directory of Open Access Journals (Sweden)

    Fabrício M. Gomes

    2006-07-01

    Full Text Available Microbial lipase from Candida rugosa was immobilized by covalent binding on wood cellulignin (Eucaliptus grandis chemically modified with carbonyldiimidazole. The immobilized system was fully evaluated in aqueous (olive oil hydrolysis and organic (ester synthesis media. A comparative study between free and immobilized lipase was carried out in terms of pH, temperature and thermal stability. A higher pH value (8.0 was found optimal for the immobilized lipase. The optimal reaction temperature shifted from 37 °C for the free lipase to 45 °C for the immobilized lipase. The pattern of heat stability indicated that the immobilization process tends to stabilize the enzyme. Kinetics tests at 37 °C following the hydrolysis of olive oil obeyed the Michaelis-Menten rate equation. Values for Km = 924.9 mM and Vmax = 198.3 U/mg were lower than for free lipase, suggesting that the affinity towards the substrate changed and the activity of the immobilized lipase decreased during the course of immobilization. The immobilized derivative was also tested in the ester synthesis from several alcohols and carboxylic acids.

  13. Structure and Function of Lipase

    DEFF Research Database (Denmark)

    Skjold-Jørgensen, Jakob

    Lipases are triacylglycerol hydrolases (EC 3.1.1.3) which are able to act on water-insoluble esters, butdisplay very low activity towards water-soluble, monomeric substrates. This is ascribed to theircharacteristic activation mechanism occurring at the boundary between water and lipid, i.e. the w......Lipases are triacylglycerol hydrolases (EC 3.1.1.3) which are able to act on water-insoluble esters, butdisplay very low activity towards water-soluble, monomeric substrates. This is ascribed to theircharacteristic activation mechanism occurring at the boundary between water and lipid, i.......e. the waterlipidinterface. For Thermomyces lanuginosus lipase (TlL) and related lipases, activation of the enzymeinvolves a rearrangement of a structural domain, called the “lid”, which covers the active site inhomogenous aqueous solution. At the water-lipid interface, the lid is displaced from the active site andmoves...... towards an open conformation enabling the substrate to gain access, thus initiating catalysis.Lipases have been studied for decades and their functional features have drawn much attention withinindustrial applications since their first discovery. However, given that their molecular action takes placeat...

  14. Synaptic basis for intense thalamocortical activation of feedforward inhibitory cells in neocortex.

    Science.gov (United States)

    Cruikshank, Scott J; Lewis, Timothy J; Connors, Barry W

    2007-04-01

    The thalamus provides fundamental input to the neocortex. This input activates inhibitory interneurons more strongly than excitatory neurons, triggering powerful feedforward inhibition. We studied the mechanisms of this selective neuronal activation using a mouse somatosensory thalamocortical preparation. Notably, the greater responsiveness of inhibitory interneurons was not caused by their distinctive intrinsic properties but was instead produced by synaptic mechanisms. Axons from the thalamus made stronger and more frequent excitatory connections onto inhibitory interneurons than onto excitatory cells. Furthermore, circuit dynamics allowed feedforward inhibition to suppress responses in excitatory cells more effectively than in interneurons. Thalamocortical excitatory currents rose quickly in interneurons, allowing them to fire action potentials before significant feedforward inhibition emerged. In contrast, thalamocortical excitatory currents rose slowly in excitatory cells, overlapping with feedforward inhibitory currents that suppress action potentials. These results demonstrate the importance of selective synaptic targeting and precise timing in the initial stages of neocortical processing.

  15. Synthesis and acetylcholinesterase inhibitory activity of polyhydroxylated sulfated steroids: structure/activity studies.

    Science.gov (United States)

    Richmond, Victoria; Murray, Ana P; Maier, Marta S

    2013-11-01

    Disulfated and trisulfated steroids have been synthesized from cholesterol and their acetylcholinesterase inhibitory activity has been evaluated. In our studies we have found that the activity was not only dependent on the location of the sulfate groups but on their configurations. 2β,3α,6α-trihydroxy-5α-cholestan-6-one trisulfate (18) was the most active steroid with an IC50 value of 15.48 μM comparable to that of 2β,3α-dihydroxy-5α-cholestan-6-one disulfate (1). Both compounds were found to be less active than the reference compound eserine. The butyrylcholinesterase activity of 1 and 18 was one magnitude lower than that against acetylcholinesterase revealing a selective inhibitor profile.

  16. ANTICARIES AND α-AMYLASE INHIBITORY ACTIVITY OF JASMINUM ARBORESCENS ROXB. (OLEACEAE LEAVES EXTRACT

    Directory of Open Access Journals (Sweden)

    Bhagath K

    2013-12-01

    Full Text Available The aim of the present study was to determine anti caries and α-amylase inhibitory activity of leaf extract of Jasminum arborescens Roxb. (Oleaceae. Anti caries activity was determined by Agar well diffusion assay against seven clinical isolates of Streptococcus mutans (Sm-01 to Sm-07 recovered from dental caries subjects. Enzyme inhibitory activity was tested against α-amylase by spectrophometric method using starch as substrate. The extract exhibited dose dependent inhibition against cariogenic isolates. Among seven isolates, isolate Sm-04 and Sm-06 were inhibited to higher and least extent respectively. The extract was found to cause inhibition of α-amylase activity in a dose dependent manner and its IC50 value was found to be 17.45 mg/ml. The inhibitory activity could be attributed to the presence of secondary metabolites. The plant may be a potential source for development of agents which are active against dental caries pathogens and for diabetes mellitus.

  17. [Lipases in catalytic reactions of organic chemistry].

    Science.gov (United States)

    Bezborodov, A M; Zagustina, N A

    2014-01-01

    Aspects of enzymatic catalysis in lipase-catalyzed reactions of organic synthesis are discussed in the review. The data on modern methods of protein engineering and enzyme modification allowing a broader range of used substrates are briefly summarized. The application of lipase in the preparation of pharmaceuticals and agrochemicals containing no inactive enantiomers and in the synthesis of secondary alcohol enantiomers and optically active amides is demonstrated. The subject of lipase involvement in the C-C bond formation in the Michael reaction is discussed. Data on the enzymatic synthesis of construction materials--polyesters, siloxanes, etc.--are presented. Examples demonstrating the application of lipase enzymatic catalysis in industry are given.

  18. Inhibitory activity of isoniazid and ethionamide against Cryptococcus biofilms.

    Science.gov (United States)

    Cordeiro, Rossana de Aguiar; Serpa, Rosana; Marques, Francisca Jakelyne de Farias; de Melo, Charlline Vládia Silva; Evangelista, Antonio José de Jesus; Mota, Valquíria Ferreira; Brilhante, Raimunda Sâmia Nogueira; Bandeira, Tereza de Jesus Pinheiro Gomes; Rocha, Marcos Fábio Gadelha; Sidrim, José Júlio Costa

    2015-11-01

    In recent years, the search for drugs to treat systemic and opportunistic mycoses has attracted great interest from the scientific community. This study evaluated the in vitro inhibitory effect of the antituberculosis drugs isoniazid and ethionamide alone and combined with itraconazole and fluconazole against biofilms of Cryptococcus neoformans and Cryptococcus gattii. Antimicrobials were tested at defined concentrations after susceptibility assays with Cryptococcus planktonic cells. In addition, we investigated the synergistic interaction of antituberculosis drugs and azole derivatives against Cryptococcus planktonic cells, as well as the influence of isoniazid and ethionamide on ergosterol content and cell membrane permeability. Isoniazid and ethionamide inhibited both biofilm formation and viability of mature biofilms. Combinations formed by antituberculosis drugs and azoles proved synergic against both planktonic and sessile cells, showing an ability to reduce Cryptococcus biofilms by approximately 50%. Furthermore, isoniazid and ethionamide reduced the content of ergosterol in Cryptococcus spp. planktonic cells and destabilized or permeabilized the fungal cell membrane, leading to leakage of macromolecules. Owing to the paucity of drugs able to inhibit Cryptococcus biofilms, we believe that the results presented here might be of interest in the designing of new antifungal compounds.

  19. Biocatalytic methanolysis activities of cross-linked protein-coated microcrystalline lipase toward esterification/transesterification of relevant palm products.

    Science.gov (United States)

    Raita, Marisa; Laosiripojana, Navadol; Champreda, Verawat

    2015-03-01

    Biocatalysis by immobilized lipase is an efficient alternative process for conversion of crude vegetable oil with high free fatty acid content to biodiesel, which is the limit of the conventional alkaline-catalyzed reaction. In this study, influences of solid-state organic and inorganic buffer core matrices with different pKa on catalytic performance of cross-linked protein coated microcrystalline biocatalysts prepared from Thermomyces lanuginosus lipase (CL-PCMC-LIP) toward esterification of palmitic acid (PA), transesterification of refined palm oil (RPO), and co-ester/transesterification of crude palm oil (CPO) to fatty acid methyl ester (FAME) was studied. Glycine, CAPSO (3-(cyclohexylamino)-2-hydroxy-1-propanesulfonic acid), and TAPS ([(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)amino]-1-propanesulfonic acid) were shown to be potent core matrices for these reactions. The optimal reaction contained 4:1 [methanol]/[fatty acid] molar equivalence ratio with 20% (w/w) CL-PCMC-LIP on glycine in the presence of tert-butanol as a co-solvent. Deactivation effect of glycerol on the biocatalyst reactive surface was shown by FTIR, which could be alleviated by increasing co-solvent content. The maximal FAME yields from PA, RPO, and CPO reached 97.6, 94.9, and 95.5%, respectively on a molar basis under the optimum conditions after incubation at 50°C for 6h. The biocatalyst retained >80% activity after recycling in five consecutive batches. The work demonstrates the potential of CL-PCMC-LIP on one-step conversion of inexpensive crude fatty acid-rich feedstock to biodiesel. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Inhibitory activity of Bifidobacterium adolescent combined with cisplatin on melanoma in mice and its mechanism

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The aim of this study is to explore inhibitory activity of Bifidobacterium adolescent combined with cisplatin on the growth of melanoma(B16)in mice and the underlying mechanism.C57 mice were inoculated with B16 cancer cells to construct mouse model of melanoma and treated with bifidobacterium adolescent combined with cisplatin.Ratios of inhibitory activity on the growth of melanoma(B 16)were calculated.Pathology changes of the tumor were observed by HE staining.B 16 cell cycles were examined on a flow cytometer.Lymphocyte proliferation was measured with MTT assay and the T-cell subset was measured by double marked fluorescence.When bifidobacterium of 1010 cfu/L was injected,the ratio of inhibitory activity on the growth of melanoma(B16)reached 54%,which was similar to that of cisplatin group.The ratio of inhibitory activity reached 74.45% when the mice were treated by bifidobacterium combined with cisplatin,HE staining shows that bifidobacterium inhibited B16 cell proliferation and enhanced the cisplati(n)s killing activity on B16 cells.The results of flow cytometry demonstrated that B16 cell proliferation was arrested at G1 stage after treatment with bifidobacterium.The B16 cell proliferation was arrested at S stage after treatment with cisplatin.The CD4+ percentage increased and the difference was significant compared with the normal group after treatment with bifidobacterium,indicating that T-cell immune activity was enhanced.Treatment with bifidobacterium combined with cisplatin can enhance the inhibitory activity on the growth of melanoma(B16)of cisplatin.The mechanism of the inhibitory activity on B 16 cell proliferation is correlated with the enhanced immune activity in mice.

  1. Discrimination and Nitric Oxide Inhibitory Activity Correlation of Ajwa Dates from Different Grades and Origin.

    Science.gov (United States)

    Abdul-Hamid, Nur Ashikin; Mediani, Ahmed; Maulidiani, M; Abas, Faridah; Ismail, Intan Safinar; Shaari, Khozirah; Lajis, Nordin H

    2016-10-28

    This study was aimed at examining the variations in the metabolite constituents of the different Ajwa grades and farm origins. It is also targeted at establishing the correlations between the metabolite contents and the grades and further to the nitric oxide (NO) inhibitory activity. Identification of the metabolites was generated using ¹H-NMR spectroscopy metabolomics analyses utilizing multivariate methods. The NO inhibitory activity was determined using a Griess assay. Multivariate data analysis, for both supervised and unsupervised approaches, showed clusters among different grades of Ajwa dates obtained from different farms. The compounds that contribute towards the observed separation between Ajwa samples were suggested to be phenolic compounds, ascorbic acid and phenylalanine. Ajwa dates were shown to have different metabolite compositions and exhibited a wide range of NO inhibitory activity. It is also revealed that Ajwa Grade 1 from the al-Aliah farm exhibited more than 90% NO inhibitory activity compared to the other grades and origins. Phenolic compounds were among the compounds that played a role towards the greater capacity of NO inhibitory activity shown by Ajwa Grade 1 from the al-Aliah farm.

  2. Improved activity of lipase immobilized in microemulsion-based organogels for (R, S-ketoprofen ester resolution: Long-term stability and reusability

    Directory of Open Access Journals (Sweden)

    Wei-Wei Zhang

    2015-09-01

    Full Text Available Microemulsion-based organogels (MBGs were effectively employed for the immobilization of four commonly used lipases. During the asymmetric hydrolysis of ketoprofen vinyl ester at 30 °C for 24 h, lipase from Rhizomucor miehei and Mucor javanicus immobilized in microemulsion-based organogels (RML MBGs and MJL MBGs maintained good enantioselectivities (eep were 86.2% and 99.2%, respectively, and their activities increased 12.8-fold and 7.8-fold, respectively, compared with their free forms. They gave higher yields compared with other lipase MBGs and exhibited better enantioselectivity than commercial immobilized lipases. Immobilization considerably increased the tolerance to organic solvents and high temperature. Both MJL MBGs and RML MBGs showed excellent reusability during 30 cycles of repeated 24 h reactions at 30 °C (over 40 days. The system maintained yields of greater than 50%, while the ees values of RML MBGs and MJL MBGs remained nearly constant at 95% and 88%, respectively.

  3. Inhibitory activities of microalgal extracts against Epstein-Barr Virus (EBV antigen expression in lymphoblastoid cells

    Directory of Open Access Journals (Sweden)

    Koh Yih Yih

    2014-01-01

    Full Text Available The inhibitory activities of microalgal extracts against the expression of three EBV antigens, latent membrane protein (LMP1, Epstein-Barr nuclear antigen (EBNA1 and Z Epstein-Barr reactivation activator (ZEBRA were assessed by immunocytochemistry. The observation that the methanol extracts and their fractions from Ankistrodesmus convolutus, Synechococcus elongatus and Spirulina platensis exhibited inhibitory activity against EBV proteins in three Burkitt’s lymphoma cell lines at concentrations as low as 20 μg/ml suggests that microalgae could be a potential source of antiviral compounds against EBV.

  4. Inhibitory Activity of (+-Usnic Acid against Non-Small Cell Lung Cancer Cell Motility.

    Directory of Open Access Journals (Sweden)

    Yi Yang

    Full Text Available Lichens are symbiotic organisms that produce various unique chemicals that can be used for pharmaceutical purposes. With the aim of screening new anti-cancer agents that inhibit cancer cell motility, we tested the inhibitory activity of seven lichen species collected from the Romanian Carpathian Mountains against migration and invasion of human lung cancer cells and further investigated the molecular mechanisms underlying their anti-metastatic activity. Among them, Alectoria samentosa, Flavocetraria nivalis, Alectoria ochroleuca, and Usnea florida showed significant inhibitory activity against motility of human lung cancer cells. HPLC results showed that usnic acid is the main compound in these lichens, and (+-usnic acid showed similar inhibitory activity that crude extract have. Mechanistically, β-catenin-mediated TOPFLASH activity and KITENIN-mediated AP-1 activity were decreased by (+-usnic acid treatment in a dose-dependent manner. The quantitative real-time PCR data showed that (+-usnic acid decreased the mRNA level of CD44, Cyclin D1 and c-myc, which are the downstream target genes of both β-catenin/LEF and c-jun/AP-1. Also, Rac1 and RhoA activities were decreased by treatment with (+-usnic acid. Interestingly, higher inhibitory activity for cell invasion was observed when cells were treated with (+-usnic acid and cetuximab. These results implied that (+-usnic acid might have potential activity in inhibition of cancer cell metastasis, and (+-usnic acid could be used for anti-cancer therapy with a distinct mechanisms of action.

  5. Understanding the molecular mechanism for the differential inhibitory activities of compounds against MTH1

    Science.gov (United States)

    Wang, Mian; Zhou, Shuilian; Chen, Qing; Wang, Lisheng; Liang, Zhiqun; Wang, Jianyi

    2017-01-01

    MTH1 can hydrolyze oxidized nucleotides and is required for cancer survival. The IC50 values were 0.8 nM for TH287 with a methyl substitution, 5.0 nM for TH588 with a cyclopropyl substitution, and 2.1 μM for TH650 with an oxetanyl substitution. Thus, it is very significant to understand inhibitory mechanisms of these structurally similar compounds against MTH1 and influences of the substituent on the bioactivities. Our MD researches indicate that TH287 maintains significant hydrogen bonds with Asn33 and Asp119, stabilizes the binding site, and induces MTH1 adopt a closed motion, leading to a high inhibitory activity. When bound with TH588, the binding site can be partially stabilized and take a semi-closed state, which is because the cyclopropyl group in TH588 has larger steric hindrance than a methyl group in TH287. So TH588 has a slightly reduced inhibitory activity compared to TH287. TH650 induces greater conformation fluctuations than TH588 and the binding site adopts an opening state, which is caused by the large bulk of oxetanyl group and the interference of solvent on the oxetanyl substituent, leading to the lowest inhibitory activity. Thus, the inhibitory activity follows a TH287 > TH588 > TH650 trend, which well matches with the experimental finding.

  6. Effect of Jatropha curcas Peptide Fractions on the Angiotensin I-Converting Enzyme Inhibitory Activity

    Directory of Open Access Journals (Sweden)

    Maira R. Segura-Campos

    2013-01-01

    Full Text Available Hypertension is one of the most common worldwide diseases in humans. Angiotensin I-converting enzyme (ACE plays an important role in regulating blood pressure and hypertension. An evaluation was done on the effect of Alcalase hydrolysis of defatted Jatropha curcas kernel meal on ACE inhibitory activity in the resulting hydrolysate and its purified fractions. Alcalase exhibited broad specificity and produced a protein hydrolysate with a 21.35% degree of hydrolysis and 34.87% ACE inhibition. Ultrafiltration of the hydrolysate produced peptide fractions with increased biological activity (24.46–61.41%. Hydrophobic residues contributed substantially to the peptides’ inhibitory potency. The 5–10 and <1 kDa fractions were selected for further fractionation by gel filtration chromatography. ACE inhibitory activity (% ranged from 22.66 to 45.96% with the 5–10 kDa ultrafiltered fraction and from 36.91 to 55.83% with the <1 kDa ultrafiltered fraction. The highest ACE inhibitory activity was observed in F2 ( μg/mL from the 5–10 kDa fraction and F1 ( μg/mL from the <1 kDa fraction. ACE inhibitory fractions from Jatropha kernel have potential applications in alternative hypertension therapies, adding a new application for the Jatropha plant protein fraction and improving the financial viability and sustainability of a Jatropha-based biodiesel industry.

  7. Xanthine oxidase inhibitory activities and crystal structures of methoxyflavones from Kaempferia parviflora rhizome.

    Science.gov (United States)

    Nakao, Kikuyo; Murata, Kazuya; Deguchi, Takahiro; Itoh, Kimihisa; Fujita, Takanori; Higashino, Masayuki; Yoshioka, Yuri; Matsumura, Shin-Ichi; Tanaka, Rika; Shinada, Tetsuro; Ohfune, Yasufumi; Matsuda, Hideaki

    2011-01-01

    Kaempferia parviflora (KP), a Zingiberaceae plant, is used as a folk medicine in Thailand for the treatment of various symptoms, including general pains, colic gastrointestinal disorders, and male impotence. In this study, the inhibitory activities of KP against xanthine oxidase (XOD) were investigated. The extract of KP rhizomes showed more potent inhibitory activity (38% at 500 µg/ml) than those of the other Zingiberaceae plants tested. Ten methoxyflavones were isolated from the KP extract as the major chemical components and their chemical structures were elucidated by X-ray crystallography. The structurally confirmed methoxyflavones were subjected to the XOD inhibitory test. Among them, 3,5,7,4',5'-pentamethoxyflavone and 3',4',5,7-tetramethoxyflavone showed inhibitory activities (IC(50) of 0.9 and >4 mM, respectively) and their modes of inhibition are clarified as competitive/non-competitive mixed type. To the best of our knowledge, this is the first report to present the inhibitory activities of KP, 3,5,7,4',5'-pentamethoxyflavone and 3',4',5,7-tetramethoxyflavone against XOD.

  8. The inhibitory effect of Curcuma longa extract on telomerase activity ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-08

    Feb 8, 2010 ... telomerase activity in A549 lung cancer cell line. Pourhassan ..... in human leukemia cell HL-60 is associated with inhibition of telomerase activity. Mol. ... metastatic non-small-cell lung cancer: a global view. BMC Proc. 2(2): p.

  9. G0/G1 switch gene-2 regulates human adipocyte lipolysis by affecting activity and localization of adipose triglyceride lipase.

    Science.gov (United States)

    Schweiger, Martina; Paar, Margret; Eder, Christina; Brandis, Janina; Moser, Elena; Gorkiewicz, Gregor; Grond, Susanne; Radner, Franz P W; Cerk, Ines; Cornaciu, Irina; Oberer, Monika; Kersten, Sander; Zechner, Rudolf; Zimmermann, Robert; Lass, Achim

    2012-11-01

    The hydrolysis of triglycerides in adipocytes, termed lipolysis, provides free fatty acids as energy fuel. Murine lipolysis largely depends on the activity of adipose triglyceride lipase (ATGL), which is regulated by two proteins annotated as comparative gene identification-58 (CGI-58) and G0/G1 switch gene-2 (G0S2). CGI-58 activates and G0S2 inhibits ATGL activity. In contrast to mice, the functional role of G0S2 in human adipocyte lipolysis is poorly characterized. Here we show that overexpression or silencing of G0S2 in human SGBS adipocytes decreases and increases lipolysis, respectively. Human G0S2 is upregulated during adipocyte differentiation and inhibits ATGL activity in a dose-dependent manner. Interestingly, C-terminally truncated ATGL mutants, which fail to localize to lipid droplets, translocate to the lipid droplet upon coexpression with G0S2, suggesting that G0S2 anchors ATGL to lipid droplets independent of ATGL's C-terminal lipid binding domain. Taken together, our results indicate that G0S2 also regulates human lipolysis by affecting enzyme activity and intracellular localization of ATGL. Increased lipolysis is known to contribute to the pathogenesis of insulin resistance, and G0S2 expression has been shown to be reduced in poorly controlled type 2 diabetic patients. Our data indicate that downregulation of G0S2 in adipose tissue could represent one of the underlying causes leading to increased lipolysis in the insulin-resistant state.

  10. Quality control evaluation and acetylcholinesterase inhibitory activity of Galanthus woronowii Losinsk

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    Ahmet Emir

    2011-05-01

    Full Text Available Aerial and underground parts ofGalanthus woronowiiLosinsk., a wild growingspecies in north-eastern Anatolia, were collected during flowering period. Quality controland acetylcholinesterase inhibitory activity determinations were carried out on Bulbus andHerba Galanthi prepared from plants collected from two different localities. In the context ofquality control studies, contents of humidity, total ash, sulphated ash, acid-insoluble ash and total alkaloids of the drug specimens were determined and found to range between8.463-9.343 %, 6.950-14.947 %, 9.743-17.930 %, 1.102-3.565 % and 0.247-0.499 %, respectively. Additionally, acetylcholinesterase inhibitory activity of the alkaloidal extracts prepared fromthe drug specimens were determined by using Thin Layer Chromatography (TLC combined with a bioautographic assay based onin vitro Ellman method. All of the alkaloidal extractsdisplayed acetylcholinesterase inhibitory activity

  11. Nutritional Composition, α-Glucosidase Inhibitory and Antioxidant Activities of Ophiopogon japonicus Tubers

    Directory of Open Access Journals (Sweden)

    Yancui Wang

    2015-01-01

    Full Text Available Ophiopogon japonicus tubers have been widely used as food and traditional Chinese medicine in China. However, their nutritional composition has not been fully reported yet. This study aimed to analyze the nutritional composition of O. japonicus tubers. The α-glucosidase inhibitory and antioxidant activities of the extracts obtained from O. japonicus tubers were also evaluated by in vitro assays. The results indicated that O. japonicus tubers are rich in carbohydrates, proteins, minerals, and amino acids. Among four extracts, the n-butanol fraction (nBF and chloroform/methanol extract (CME of O. japonicus tubers had high amounts of total phenolic and flavonoid contents and exhibited good α-glucosidase inhibitory and antioxidant activities. The α-glucosidase inhibition of nBF was higher than acarbose. Overall, O. japonicus tubers are full of nutritional compounds and have good α-glucosidase inhibitory and antioxidant activities.

  12. Alpha-Glucosidase Inhibitory and Antioxidant Activity of Solvent ...

    African Journals Online (AJOL)

    Methods: Extracts were prepared using hexane, chloroform, ethyl acetate, acetone (AE), methanol, ... screening has revealed moderate antiglucosidase and antioxidant activities in the ... glucosidase inhibitor in vivo and in vitro has been.

  13. Ring-Closing and Cross-Metathesis with Artificial Metalloenzymes Created by Covalent Active Site-Directed Hybridization of a Lipase.

    Science.gov (United States)

    Basauri-Molina, Manuel; Verhoeven, Dide G A; van Schaik, Arnoldus J; Kleijn, Henk; Klein Gebbink, Robertus J M

    2015-10-26

    A series of Grubbs-type catalysts that contain lipase-inhibiting phosphoester functionalities have been synthesized and reacted with the lipase cutinase, which leads to artificial metalloenzymes for olefin metathesis. The resulting hybrids comprise the organometallic fragment that is covalently bound to the active amino acid residue of the enzyme host in an orthogonal orientation. Differences in reactivity as well as accessibility of the active site by the functionalized inhibitor became evident through variation of the anchoring motif and substituents on the N-heterocyclic carbene ligand. Such observations led to the design of a hybrid that is active in the ring-closing metathesis and the cross-metathesis of N,N-diallyl-p-toluenesulfonamide and allylbenzene, respectively, the latter being the first example of its kind in the field of artificial metalloenzymes.

  14. Inhibitory effects of cefotaxime on the activity of mushroom tyrosinase.

    Science.gov (United States)

    Hu, Yong-Hua; Zhuang, Jiang-Xing; Yu, Feng; Cui, Yi; Yu, Wen-Wen; Yan, Chong-Ling; Chen, Qing-Xi

    2016-04-01

    Tyrosinase (EC 1.14.18.1) catalyzes both the hydroxylation of tyrosine into o-diphenols and the oxidation of o-diphenols into o-quinones that form brown or black pigments. In the present paper, cefotaxime, a cephalosporin antibacterial drug, was tested as an inhibitor of tyrosinase. The results show that cefotaxime inhibits both the monophenolase and diphenolase activities of tyrosinase. For the monophenolase activity, cefotaxime increased the lag time and decreased the steady-state activity with an IC50 of 3.2 mM. For the diphenolase activity, the inhibition by cefotaxime is reversible and mix-I type with an IC50 of 0.14 mM. The inhibition constants (K(I) and K(IS)) were determined to be 0.14 and 0.36 mM, respectively. The molecular mechanism of inhibition of tyrosinase by cefotaxime was determined by fluorescence quenching and molecular docking. The results demonstrated that cefotaxime was a static quencher of tyrosinase and that cefotaxime could dock favorably in the active site of tyrosinase. This research may offer a lead for designing and synthesizing novel and effective tyrosinase inhibitors in the future.

  15. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production

    Directory of Open Access Journals (Sweden)

    Tomohiro Furukawa

    2016-06-01

    Full Text Available Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control.

  16. Costus afer Possesses Carbohydrate Hydrolyzing Enzymes Inhibitory Activity and Antioxidant Capacity In Vitro

    Directory of Open Access Journals (Sweden)

    Armelle D. Tchamgoue

    2015-01-01

    Full Text Available Diabetes mellitus is a metabolic disorder of glucose metabolism which correlates with postprandial hyperglycemia and oxidative stress. Control of blood glucose level is imperative in the management of diabetes. The present study tested the hypothesis that Costus afer, an antihyperglycemic medicinal plant, possesses inhibitory activity against carbohydrate hydrolyzing enzymes. Hexane, ethyl acetate, methanol, and water extracts were prepared from the leaf, stem, and rhizome of C. afer and subjected to phytochemical screening, assayed for α-amylase and α-glucosidase inhibitory activities and antioxidant capacity (determined by total phenolic and total flavonoids contents, ferric reducing antioxidant power (FRAP, and DPPH radical scavenging activity. All extracts inhibited α-amylase and α-glucosidase activities. Ethyl acetate rhizome and methanol leaf extracts exhibited the best inhibitory activity against α-amylase and α-glucosidase (IC50: 0.10 and 5.99 mg/mL, respectively. Kinetic analysis revealed two modes of enzyme inhibition (competitive and mixed. All extracts showed antioxidant capacity, with hexane extracts exhibiting the best activity. DPPH assay revealed that methanol leaf, rhizome, and ethyl acetate stem extracts (IC50 < 5 mg/mL were the best antioxidants. The presence of bioactive compounds such as flavonoids, alkaloids, phenols, and tannins may account for the antioxidant capacity and carbohydrate hydrolyzing enzyme inhibitory activity of C. afer.

  17. Screening for acetylcholinesterase inhibitory activity in cyanobacteria of the genus Nostoc.

    Science.gov (United States)

    Zelík, Petr; Lukesová, Alena; Voloshko, Ludmila N; Stys, Dalibor; Kopecký, Jirí

    2009-04-01

    Fifty-four cyanobacterial strains of the genus Nostoc from different habitats were screened for acetylcholinesterase inhibitory activity. Water-methanolic extracts from freeze-dried biomasses were tested for inhibitory activity using Ellman's spectrophotometric method. Acetylcholinesterase inhibitory activity higher than 90% was found in the crude extracts of Nostoc sp. str. Lukesova 27/97 and Nostoc ellipsosporum Rabenh. str. Lukesova 51/91. Extracts from Nostoc ellipsosporum str. Lukesova 52/91 and Nostoc linckia f. muscorum (Ag.) Elenk. str. Gromov, 1988, CALU-980 inhibited AChE activity by 84.9% and 65.3% respectively. Moderate AChE inhibitory activity (29.1-37.5%) was found in extracts of Nostoc linckia Roth. str. Gromov, 1962/10, CALU-129, Nostoc muscorum Ag. str. Lukesova 127/97, Nostoc sp. str. Lhotsky, CALU-327 and Nostoc sp. str. Gromov, CALU-998. Extracts from another seven strains showed weak anti-AChE activities. The active component responsible for acetylcholinesterase inhibition was identified in a crude extract of Nostoc sp. str. Lukesova 27/97 using HPLC and found to occur in one single peak.

  18. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production

    Science.gov (United States)

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-01-01

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control. PMID:27338472

  19. Costus afer Possesses Carbohydrate Hydrolyzing Enzymes Inhibitory Activity and Antioxidant Capacity In Vitro

    Science.gov (United States)

    Tchamgoue, Armelle D.; Tchokouaha, Lauve R. Y.; Tarkang, Protus A.; Kuiate, Jules-Roger; Agbor, Gabriel A.

    2015-01-01

    Diabetes mellitus is a metabolic disorder of glucose metabolism which correlates with postprandial hyperglycemia and oxidative stress. Control of blood glucose level is imperative in the management of diabetes. The present study tested the hypothesis that Costus afer, an antihyperglycemic medicinal plant, possesses inhibitory activity against carbohydrate hydrolyzing enzymes. Hexane, ethyl acetate, methanol, and water extracts were prepared from the leaf, stem, and rhizome of C. afer and subjected to phytochemical screening, assayed for α-amylase and α-glucosidase inhibitory activities and antioxidant capacity (determined by total phenolic and total flavonoids contents, ferric reducing antioxidant power (FRAP), and DPPH radical scavenging activity). All extracts inhibited α-amylase and α-glucosidase activities. Ethyl acetate rhizome and methanol leaf extracts exhibited the best inhibitory activity against α-amylase and α-glucosidase (IC50: 0.10 and 5.99 mg/mL), respectively. Kinetic analysis revealed two modes of enzyme inhibition (competitive and mixed). All extracts showed antioxidant capacity, with hexane extracts exhibiting the best activity. DPPH assay revealed that methanol leaf, rhizome, and ethyl acetate stem extracts (IC50 < 5 mg/mL) were the best antioxidants. The presence of bioactive compounds such as flavonoids, alkaloids, phenols, and tannins may account for the antioxidant capacity and carbohydrate hydrolyzing enzyme inhibitory activity of C. afer. PMID:26246844

  20. Cylindrocyclophanes with Proteasome Inhibitory Activity from the Cyanobacterium Nostoc sp

    Science.gov (United States)

    Chlipala, George E.; Sturdy, Megan; Krunic, Aleksej; Lantvit, Daniel D.; Shen, Qi; Porter, Kyle; Swanson, Steven M.; Orjala, Jimmy

    2010-01-01

    Material collected from a parkway in the city of Chicago afforded the isolation of a Nostoc species (UIC 10022A). The extract of this strain displayed significant inhibition of the 20S proteasome as well as antiproliferative activity against HT29, MCF7, NCI-H460, and SF268 cancer cell lines. A standardized dereplication protocol allowed for the rapid identification of three known (11-13) and nine new (1-9) chlorinated cylindrocyclophanes from less than 100 mg of organic extract. Scale-up isolation of 1-9 and 11-13 from a larger extract was guided by LC-UV-MS data. In addition, KBr enrichment of the culture media afforded the isolation of a brominated cylindrocyclophane (10). Biological evaluation of 1-5, 9, and 10-13 revealed a large range of activity against the 20S proteasome and allowed the determination of preliminary structure-activity relationships (SAR) of the cylindrocyclophane pharmacophore. PMID:20825206

  1. GC-MS investigation and acetylcholinesterase inhibitory activity of Galanthus rizehensis.

    Science.gov (United States)

    Sarikaya, Buket Bozkurt; Somer, Nehir Unver; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Berkov, Strahil

    2013-01-01

    GC-MS (gas chromatography-mass spectrometry) analyses of alkaloids in the aerial parts and bulbs of Galanthus rizehensis Stern (Amaryllidaceae), collected during two different vegetation periods, was performed. Twenty three alkaloids were identified in four different alkaloid extracts. Acetylcholinesterase (AChE) inhibitory activities of the alkaloid extracts were tested. Both the highest alkaloid diversity and the most potent inhibitory activity (IC50 12.94 microg/ml) were obtained in extracts from the bulbs of G. rizehensis collected during the fruiting period.

  2. Inhibitory activity of postbiotic produced by strains of Lactobacillus plantarum using reconstituted media supplemented with inulin

    OpenAIRE

    Kareem, Karwan Yassen; Hooi Ling, Foo; Teck Chwen, Loh; May Foong, Ooi; Anjas Asmara, Samsudin

    2014-01-01

    Background The present study aimed to determine the inhibitory activity of postbiotic produced by L. plantarum using reconstituted media supplemented with different levels of inulin and to select the best combination based on the modified inhibitory activity (MAU/mL) against pathogens. Methods Postbiotics were produced by 6 strains of L. plantarum (RG11, RG14, RI11, UL4, TL1 and RS5) using reconstituted media supplemented with different levels of Inulin (0, 0.2, 0.4, 0.6, 0.8, and 1.0) yieldi...

  3. Phytochemical Analysis of Agrimonia pilosa Ledeb, Its Antioxidant Activity and Aldose Reductase Inhibitory Potential

    Science.gov (United States)

    Kim, Set Byeol; Hwang, Seung Hwan; Suh, Hong-Won; Lim, Soon Sung

    2017-01-01

    The aim of this study was to determine aldose reductase (AR) inhibitory activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of compounds from Agrimonia pilosa Ledeb (AP). We isolated agrimoniin (AM), four flavonoid glucosides and two flavonoid glucuronides from the n-butanol fraction of AP 50% methanol extract. In addition to isolated compounds, the AR-inhibitory activity and the DPPH free radical scavenging activity of catechin, 5-flavonoids, and 4-flavonoid glucosides (known components of AP) against rat lens AR (RLAR) and DPPH assay were measured. AM showed IC50 values of 1.6 and 13.0 μM against RLAR and DPPH scavenging activity, respectively. Additionally, AM, luteolin-7-O-glucuronide (LGN), quercitrin (QU), luteolin (LT) and afzelin (AZ) showed high inhibitory activity against AR and were first observed to decrease sorbitol accumulation in the rat lens under high-sorbitol conditions ex vivo with inhibitory values of 47.6%, 91.8%, 76.9%, 91.8% and 93.2%, respectively. Inhibition of recombinant human AR by AM, LGN and AZ exhibited a noncompetitive inhibition pattern. Based on our results, AP and its constituents may play partial roles in RLAR and oxidative radical inhibition. Our results suggest that AM, LGN, QU, LT and AZ may potentially be used as natural drugs for treating diabetic complications. PMID:28208627

  4. Design and Synthesis of Norendoxifen Analogues with Dual Aromatase Inhibitory and Estrogen Receptor Modulatory Activities

    Science.gov (United States)

    Lv, Wei; Liu, Jinzhong; Skaar, Todd C.; Flockhart, David A.; Cushman, Mark

    2015-01-01

    Both selective estrogen receptor modulators and aromatase inhibitors are widely used for the treatment of breast cancer. Compounds with both aromatase inhibitory and estrogen receptor modulatory activities could have special advantages for treatment of breast cancer. Our previous efforts led to the discovery of norendoxifen as the first compound with dual aromatase inhibitory and estrogen receptor binding activities. To optimize its efficacy and aromatase selectivity versus other cytochrome P450 enzymes, a series of structurally related norendoxifen analogues were designed and synthesized. The most potent compound, 4'-hydroxynorendoxifen (10), displayed elevated inhibitory potency against aromatase and enhanced affinity for estrogen receptors when compared to norendoxifen. The selectivity of 10 for aromatase versus other cytochrome P450 enzymes was also superior to norendoxifen. 4'-Hydroxynorendoxifen is therefore an interesting lead for further development to obtain new anticancer agents of potential value for the treatment of breast cancer. PMID:25751283

  5. Ultrasonic extraction of polysaccharides from Laminaria japonica and their antioxidative and glycosidase inhibitory activities

    Science.gov (United States)

    Wan, Peng; Yang, Xiaoman; Cai, Bingna; Chen, Hua; Sun, Huili; Chen, Deke; Pan, Jianyu

    2015-08-01

    In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Laminaria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80°C and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% ± 0.3%) is close to the predicted result (5.67%) with no significant difference ( P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ± 2.19%, 3.0 mg mL-1). Also, the inhibitory activity against α-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-1). LJP1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80% ± 0.00%, 3.0 mg mL-1) and moderate α-glucosidase inhibitory activity (47.76% ± 1.92%, 5.0 mg mL-1). LJP shows the most remarkable DPPH scavenging activity (66.20% ± 0.11%, 5.0 mg mL-1) but weakest α-glucosidase inhibitory activity (37.77% ± 1.30%, 5.0 mg mL-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of

  6. Acetylcholinesterase inhibitory activity of pyrrolizidine alkaloids from Echium confusum Coincy.

    Science.gov (United States)

    Benamar, Houari; Tomassini, Lamberto; Venditti, Alessandro; Marouf, Abderrazak; Bennaceur, Malika; Serafini, Mauro; Nicoletti, Marcello

    2017-06-01

    Four pyrrolizidine alkaloids, namely 7-O-angeloyllycopsamine N-oxide 1, echimidine N-oxide 2, echimidine 3 and 7-O-angeloylretronecine 4, were isolated for the first time from the whole plant ethanolic extract of Echium confusum Coincy, through bioassay-guided approach. Their structures were determined by spectroscopic means. All the isolates compounds showed moderate activities in inhibiting AChE, with IC50 0.276-0.769.

  7. Effects of essential oils from herbal plants and citrus fruits on DNA polymerase inhibitory, cancer cell growth inhibitory, antiallergic, and antioxidant activities.

    Science.gov (United States)

    Mitoshi, Mai; Kuriyama, Isoko; Nakayama, Hiroto; Miyazato, Hironari; Sugimoto, Keiichiro; Kobayashi, Yuko; Jippo, Tomoko; Kanazawa, Kazuki; Yoshida, Hiromi; Mizushina, Yoshiyuki

    2012-11-14

    In this study, the biological activity of 20 essential oils (EOs) from herbal plants and citrus fruits were investigated in terms of mammalian DNA polymerase (pol) inhibitory activity, cancer cell (human colon carcinoma, HCT116) growth inhibitory activity, antiallergic activity, as anti-β-hexosaminidase release activity in rat basophilic leukemia RBL-2H3 cells treated with calcium ionophore A23187, and antioxidant activity by a lipophilic-oxygen radical absorbance capacity method. These EOs showed patterns of inhibition of pol α, a DNA replicative pol, similar to their cancer cell growth inhibitory activity, and their inhibitory activity on pol λ, a DNA repair/recombination pol, by the EOs showed correlation with anti-β-hexosaminidase release activity. Among these EOs, chamomile (Matricaria chamomilla L.) was the strongest inhibitor of pols α and λ and showed significant effects on both cancer cell growth and mast cell degranulation. On the basis of these results, chamomile EO can be recommended as a potentially useful, bioactive candidate for therapeutic applications.

  8. Familial lipoprotein lipase deficiency

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000408.htm Familial lipoprotein lipase deficiency To use the sharing features on this page, please enable JavaScript. Familial lipoprotein lipase deficiency is a group of rare genetic ...

  9. Cardiac lipoprotein lipase activity in the hypertrophied heart may be regulated by fatty acid flux.

    Science.gov (United States)

    Hauton, David; Caldwell, Germaine M

    2012-04-01

    Cardiac hypertrophy is characterised by an imbalance between lipid uptake and fatty acid β-oxidation leading to an accumulation of lipids, particularly triacylglycerol (TAG). It is unclear whether uptake mechanisms such as lipoprotein lipase (LPL) can be attenuated to diminish this uptake. Rats were cold acclimated to induce cardiac hypertrophy and increase cardiac LPL. Lipid uptake and metabolism were altered by feeding a 'Western-style' high fat diet (WSD) or feeding oxfenicine (2g/L) in the drinking water. Diastolic stiffness (increased volume change/unit pressure change) was induced in hypertrophied hearts for rats fed WSD (Pmuscle, estimated from stress-strain calculations was unchanged. Cold acclimation increased cardiac endothelial LPL (P<0.05) but this was diminished following oxfenicine. Following WSD LPL was further decreased below WSD-fed control hearts (P<0.05) with no further decrease by oxfenicine supplementation. A negative correlation was noted between plasma TAG and endothelial LPL (correlation coefficient=-0.654; P<0.001) but not cardiac TAG concentration. Transcript levels of angiopoietin-like protein-4 (ANGPTL4) were increased 6-fold by WSD (P<0.05) and increased 15-fold following WSD+oxfenicine (P<0.001). For CA-hearts fed WSD or WSD+oxfenicine ANGPTL4 mRNA levels were preserved at chow-fed levels. VLDLR protein levels were increased 10-fold (P<0.01) by CA. ANGPTL4 protein levels were increased 2-fold (P<0.05) by WSD, but restored following oxfenicine. For CA-hearts WSD increased ANGPTL4 protein levels 3-fold (P<0.01) with WSD+oxfenicine increasing ANGPTL4 protein 4-fold (P<0.01). These data suggest that endothelial LPL levels in the heart are altered to maintain FA flux and may exploit ANGPTL4. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Specificity of, and influence of hemolysis, lipemia, and icterus on serum lipase activity as measured by the v-LIP-P slide.

    Science.gov (United States)

    Steiner, Joerg M; Gomez, Robynne; Suchodolski, Jan S; Lidbury, Jonathan A

    2017-06-21

    Measurement of pancreatic lipase in serum is being used for the diagnosis of pancreatitis. The aims of this study were to measure serum lipase activity by the v-LIP-P slide and serum canine pancreatic lipase immunoreactivity (cPLI) concentration by Spec cPL in dogs with exocrine pancreatic insufficiency (EPI) and in serum samples that were hemolyzed, lipemic, or icteric. Serum samples from 50 dogs with EPI, 8 samples spiked with canine hemoglobin, Intralipid, or ditaurobilirubin, and 8 samples from dogs with severe hypertriglyceridemia were evaluated using v-LIP-P and Spec cPL assays. Serum lipase activity (v-LIP-P) was in the lower 20% of the RI in 58% of EPI dogs, while serum cPLI (as measured by Spec cPL) was in the lower 20% of the RI in 98% of EPI dogs. The mean (±SD) observed-to-expected ratios for serum samples spiked with canine hemoglobin, Intralipid, or ditaurobilirubin were 63.0 ± 25.1%, 489.2 ± 469.7%, and 80.2 ± 11.6% for the v-LIP-P slide, respectively, and 99.3 ± 6.8%, 96.9 ± 9.4%, and 98.7 ± 11.0% for Spec cPL, respectively. However, naturally occurring hypertriglyceridemia did not appear to have a significant effect on serum lipase activity as measured by the v-LIP-P slide. These results show that Spec cPL is specific for pancreatic lipase, while the v-LIP-P slide is not. In addition, hemolysis and lipemia had no effect on Spec cPL, while severe icterus resulted in a slight decrease in Spec cPL. Hemolysis and icterus had a significant effect on the v-LIP-P slide. The effect of lipemia on the v-LIP-P slide cannot be conclusively established based on this study. © 2017 American Society for Veterinary Clinical Pathology.

  11. Nitrogen dioxide induced changes in level of free fatty acids, triglyceride, esterified fatty acid, ganglioside and lipase activity in the guinea pig brain

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, H.; Hasan, M. (Interdisciplinary Brain Research Centre, Jawaharlal Nehru Medical College, Aligarh Muslim University, (India))

    1992-02-01

    The biochemical response to controlled inhalation of nitrogen dioxide (NO2) was studied in 18 male guinea pigs. Animals were exposed to 2.5, 5.0, and 10 ppm NO2 for 2h daily for 35 consecutive days, and the results compared with six control animals exposed to filtered air for 2h daily for same period. Five biochemical parameters, including triglyceride, free fatty acids, esterified fatty acid, ganglioside and lipase activity were measured immediately after the last day of exposure. At 2.5 ppm NO2 inhalation no significant changes occurred in any region of the central nervous system (CNS). While as the dose concentration was increased to 5 and 10 ppm nitrogen dioxide, significant dose-related alteration were observed in the levels of triglyceride, free fatty acid, esterified fatty acid, ganglioside and lipase activity in the different regions of the guinea pig CNS.

  12. Culture Conditions of Psychrotrophic Fungus, Penicillium chrysogenum and Its Lipase Characteristics

    OpenAIRE

    Bsncerz, Renata; Ginalska, Grazyna; Leonowicz, Andrzej; Oga, Shoji

    2007-01-01

    Among 97 fungal strains from the soil collected from the high mountain areas in the Jeju Island, Korea, Penicillium chrysogenum 9 was found to be the best lipase producer. Its lipase productivity reached 42 U/ml in the culture medium. Factors affecting lipase production by Penicillium chrysogenum 9 were studied using fermentation media of different chemical compositions. Under optimal conditions we noted a 1.6-fold increase of lipase activity. The maximum lipase activity was 68 U/ml of cultur...

  13. An Update on Natural Products with Carbonic Anhydrase Inhibitory Activity.

    Science.gov (United States)

    Karioti, Anastasia; Carta, Fabrizio; Supuran, Claudiu T

    2016-01-01

    Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the fundamental reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological processes. They represent a typical example of enzyme convergent evolution, as six genetically unrelated families of such enzymes were described so far. It is more than 70 years that synthetic compounds, mainly sulfonamides, have been used in clinical practice as diuretics and systemic acting antiglaucoma drugs. Recent studies using natural product libraries and isolated constituents from natural sources (such as fungi and plants) have disclosed novel chemotypes possessing carbonic anhydrase inhibition activities. These natural sources offer new opportunities in the search for new and more effective carbonic anhydrase inhibitors, and may serve as new leads for the design and development of future drugs. This review will discuss the most recent advances in the search of naturally occurring products and their synthetic derivatives that inhibit the CAs and their mechanisms of action at molecular level. Plant extracts are not considered in the present review.

  14. Crystal structure of Proteus mirabilis lipase, a novel lipase from the Proteus/psychrophilic subfamily of lipase family I.1.

    Directory of Open Access Journals (Sweden)

    Tyler P Korman

    Full Text Available Bacterial lipases from family I.1 and I.2 catalyze the hydrolysis of triacylglycerol between 25-45°C and are used extensively as biocatalysts. The lipase from Proteus mirabilis belongs to the Proteus/psychrophilic subfamily of lipase family I.1 and is a promising catalyst for biodiesel production because it can tolerate high amounts of water in the reaction. Here we present the crystal structure of the Proteus mirabilis lipase, a member of the Proteus/psychrophilic subfamily of I.1lipases. The structure of the Proteus mirabilis lipase was solved in the absence and presence of a bound phosphonate inhibitor. Unexpectedly, both the apo and inhibitor bound forms of P. mirabilis lipase were found to be in a closed conformation. The structure reveals a unique oxyanion hole and a wide active site that is solvent accessible even in the closed conformation. A distinct mechanism for Ca²⁺ coordination may explain how these lipases can fold without specific chaperones.

  15. Urease Inhibitory Activities of some Commonly Consumed Herbal Medicines.

    Science.gov (United States)

    Mahernia, Shabnam; Bagherzadeh, Kowsar; Mojab, Faraz; Amanlou, Massoud

    2015-01-01

    Urease enzyme has a crucial role in the persistent habitation of Helicobacter pylori (H. pylori) that induces gastrointestinal diseases, in particular gastritis, duodenal, peptic ulcer, and gastric cancer. Plants have long been utilized as the biggest source of substances with medicinal properties from natural origin and therefore result in less toxicity and adverse side effects upon usage. 15 medicinal plant extracts were examined against Jack bean urease activity by Berthelot reaction. Each herb was extracted using 80% aqueous methanol. The more effective extracts were further tested and their IC50 values were determined. Three plant extracts including Ginkgo biloba, Rhus coriaria, and Matricaria inodora were found to be the most effective ones with IC50 values of 36.17, 80.29, and 100.6 μg/mL, respectively.

  16. Extracellular lipase of Pseudomonas aeruginosa: biochemical characterization and effect on human neutrophil and monocyte function in vitro

    DEFF Research Database (Denmark)

    Jaeger, K E; Kharazmi, A; Høiby, N

    1991-01-01

    on neutrophils. The inhibitory effect was concentration dependent and was abolished by heat treatment of the enzyme at 100 degrees C. Since monocytes are one of the important cells of the host defence system the inhibition of the function of these cells may contribute to the pathogenesis of infections caused...... concentrations of this lipase preparation were preincubated with human peripheral blood neutrophils and monocytes. The chemotaxis and chemiluminescence of these cells were then determined. It was shown that lipase inhibited the monocyte chemotaxis and chemiluminescence, whereas it had no or very little effect...... chromatography revealed spherical particles with diameters ranging from 5 to 20 nm. Biochemical characterization and SDS polyacrylamide gel electrophoresis suggested that these particles consisted of protein and carbohydrate including lipopolysaccharide with the major enzyme activity being lipase. Various...

  17. MICROBIAL LIPASES: PRODUCTION OF EXTRACELLULAR LIPASE ENZYME BY ALCALIGENES VISCOSUS (DOGE-1 STRAIN

    Directory of Open Access Journals (Sweden)

    P.Sekhar

    2012-05-01

    Full Text Available Industrially important extracellular lipase enzyme production was explored by utilizingmicrobial strain isolated from dairy effluents. Alcaligenes viscosus DOGE-1 strain isolated from dairywaste waters proved to produce extracellular lipase. Various growth factors were attempted to maximizethe lipase production by this strain. Growth factors like NH4PO4, Peptone, Urea coupled with peptone,KH2PO4, Olive oil and pH were found to be favored the maximum lipase production. This microbialstrain was found to have a high lipolytic activity.

  18. trans-10, cis-12 Conjugated linoleic acid inhibits lipoprotein lipase but increases the activity of lipogenic enzymes in adipose tissue from hamsters fed an atherogenic diet

    OpenAIRE

    Zabala, Amaia; Churruca Ortega, Itziar; Fernández Quintela, Alfredo; Rodríguez Rivera, Víctor Manuel; Macarulla Arenaza, María Teresa; Martínez, J Alfredo; Portillo Baquedano, María Puy

    2006-01-01

    The aim of the present work was to investigate the effects of trans-10,cis-12conjugated linoleic acid (CLA) on the activity and expression of lipogenic enzymes and lipoprotein lipase (LPL), as well as on the expression of transcriptional factors controlling these enzymes, in adipose tissue from hamsters, and to evaluate the involvement of these changes in the body fat-reducing effect of this CLA isomer. Thirty male hamsters were divided into three groups and fed atherogenic diets supplemented...

  19. Nanonets Derived from Turnip Mosaic Virus as Scaffolds for Increased Enzymatic Activity of Immobilized Candida antarctica Lipase B.

    Science.gov (United States)

    Cuenca, Sol; Mansilla, Carmen; Aguado, Marta; Yuste-Calvo, Carmen; Sánchez, Flora; Sánchez-Montero, Jose M; Ponz, Fernando

    2016-01-01

    Elongated flexuous plant viral nanoparticles (VNPs) represent an interesting platform for developing different applications in nanobiotechnology. In the case of potyviruses, the virion external surface is made up of helically arrayed domains of the viral structural coat protein (CP), repeated over 2000 times, in which the N- and C-terminal domains of each CP are projected toward the exterior of the external virion surface. These characteristics provide a chemical environment rich in functional groups susceptible to chemical conjugations. We have conjugated Candida antarctica lipase B (CALB) onto amino groups of the external surface of the potyvirus turnip mosaic virus (TuMV) using glutaraldehyde as a conjugating agent. Using this approach, TuMV virions were transformed into scaffolds for CALB nanoimmobilization. Analysis of the resulting structures revealed the formation of TuMV nanonets onto which large CALB aggregates were deposited. The functional enzymatic characterization of the CALB-bearing TuMV nanonets showed that CALB continued to be active in the nanoimmobilized form, even gaining an increased relative specific activity, as compared to the non-immobilized form. These novel virus-based nanostructures may provide a useful new approach to enzyme nanoimmobilization susceptible to be industrially exploited.

  20. Enhancement of Lipase Enzyme Activity in Non-Aqueous Media through a Rapid Three Phase Partitioning and Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    N. Saifuddin

    2008-01-01

    Full Text Available Three phase partitioning is fast developing as a novel bio-separation strategy with a wide range of applications including enzyme stability and enhancement of its catalytic activity. pH tuning of enzyme is now well known for use in non-aqueous systems. Tuned enzyme was prepared using a rapid drying technique of microwave dehydration (time required around 15 minutes. Further enhancement was achieved by three phase partitioning (TPP method. With optimal condition of ammonium sulphate and t-butanol, the protein appeared as an interfacial precipitate between upper t-butanol and lower aqueous phases. In this study we report the results on the lipase which has been subjected to pH tuning and TPP, which clearly indicate the remarkable increase in the initial rate of transesterification by 3.8 times. Microwave irradiation was found to increase the initial reaction rates by further 1.6 times, hence giving a combined increase in activity of about 5.4 times. Hence it is shown that microwave irradiation can be used in conjunction with other strategies (like pH tuning and TPP for enhancing initial reaction rates.

  1. Nanonets derived from turnip mosaic virus as scaffolds for increased enzymatic activity of immobilized Candida antarctica lipase B

    Directory of Open Access Journals (Sweden)

    Sol eCuenca

    2016-04-01

    Full Text Available Elongated flexuous plant viral nanoparticles (VNPs represent an interesting platform for developing different applications in nanobiotechnology. In the case of potyviruses, the virion external surface is made up of helically-arrayed domains of the viral structural coat protein (CP, repeated over 2000 times, in which the N- and C-terminal domains of each CP are projected towards the exterior of the external virion surface. These characteristics provide a chemical environment rich in functional groups susceptible to chemical conjugations. We have conjugated Candida antarctica lipase B (CALB onto amino groups of the external surface of the potyvirus turnip mosaic virus (TuMV using glutaraldehyde as a conjugating agent. Using this approach, TuMV virions were transformed into scaffolds for CALB nanoimmobilization. Analysis of the resulting structures revealed the formation of TuMV nanonets onto which large CALB aggregates were deposited. The functional enzymatic characterization of the CALB-bearing TuMV nanonets showed that CALB continued to be active in the nanoimmobilized form, even gaining an increased relative specific activity, as compared to the non-immobilized form. These novel virus-based nanostructures may provide a useful new approach to enzyme nanoimmobilization susceptible to be industrially exploited.

  2. Acid Lipase Disease

    Science.gov (United States)

    ... Page You are here Home » Disorders » All Disorders Acid Lipase Disease Information Page Acid Lipase Disease Information Page What research is being ... research to understand lipid storage diseases such as acid lipase deficiency. Additional research studies hope to identify ...

  3. Xanthine Oxidase Inhibitory Activity of a Plectranthus saccatus aqueous extract

    Directory of Open Access Journals (Sweden)

    Caldeira F

    2016-12-01

    Full Text Available Gout is a disease with high prevalence in developed countries, resulting from the deposition of uric acid crystals in various locations, particularly at the joints. The pharmacotherapeutic approach to chronic gout essentially consists of administration of uric acid-lowering agents. The main mechanism of action of these agents is the inhibition of xanthine oxidase (XO, the enzyme responsible for the formation of uric acid. The therapeutic alternatives available for this purpose are limited, thus justifying the interest of the discovery of potential new uric acidlowering drugs. In this regard, an aqueous extract of the plant Plectranthus saccatus has been studied for its ability to inhibit XO. The composition of the extract was determined by HPLC and rosmarinic acid was identified as the major constituent. Both the extract and rosmarinic acid have demonstrated the ability to inhibit the production of uric acid by interfering with XO activity. The results obtained herein support the continuation of the study of their uric acid-lowering properties in cell-based and in vivo models to further explore their potential in gout therapy.

  4. A Bisindole Alkaloid with Hedgehog Signal Inhibitory Activity from the Myxomycete Perichaena chrysosperma.

    Science.gov (United States)

    Shintani, Akinori; Toume, Kazufumi; Rifai, Yusnita; Arai, Midori A; Ishibashi, Masami

    2010-10-22

    6-Hydroxy-9'-methoxystaurosporinone (1), a new bisindole alkaloid, was isolated from field-collected fruiting bodies of the myxomycete Perichaena chrysosperma, together with two known compounds. The structure of the new alkaloid was elucidated from spectral data, and compound 1 was shown to have hedgehog signal inhibitory activity. A related new alkaloid, 6,9'-dihydroxystaurosporinone (4), was also isolated from Arcyria cinerea.

  5. Chrotacumines G-J, chromone alkaloids from Dysoxylum acutangulum with osteoclast differentiation inhibitory activity.

    Science.gov (United States)

    Morita, Hiroshi; Nugroho, Alfarius Eko; Nagakura, Yuta; Hirasawa, Yusuke; Yoshida, Haruka; Kaneda, Toshio; Shirota, Osamu; Ismail, Intan Safinar

    2014-06-01

    Four new chromone alkaloids, chrotacumines G-J (1-4), have been isolated from the barks of Dysoxylum acutangulum. Their structures and absolute configurations were elucidated on the basis of NMR and CD data. Chrotacumines G and J (1 and 4) showed osteoclast differentiation inhibitory activity in a dose dependent manner. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Xanthine oxidase inhibitory activity of some leafy vegetables collected from Palakkad regions of Kerala

    Directory of Open Access Journals (Sweden)

    L. SUTHARSON

    2016-01-01

    Full Text Available Sauropus androgynus, Aerva lanata & Benincasa hispida have been using as leafy vegetable in kerala. The investigation undertaken was aimed to study xanthine oxidase (XO inhibitory activity of these three plants and it was demonstrated the usefulness and beneficial effects in the treatment of Gout. Inhibition of XO is an effective therapeutic approach for treating hyperuricemia that causes gout. Allopurinol, a known inhibitor of XO, was used to validate the method and was adopted as positive control in the studies. The degree of inhibition was determined by measuring the increase in absorbance at 295 nm associated with uric acid formation. Aerva lanata showed a significant XO inhibitory activity with an IC50 value of 62.53μg/ml. Benincasa hispida and Sauropus androgynus showed a moderate significant XO inhibitory activity with an IC50 value of 67.97μg/ml,80.12 μg/ml respectively. The study recommended that leaves possess XO inhibitory activity that might be useful in preventing or slow down the progress of gout.

  7. Bistability Analysis of Excitatory-Inhibitory Neural Networks in Limited-Sustained-Activity Regime

    Institute of Scientific and Technical Information of China (English)

    倪赟; 吴亮; 吴丹; 朱士群

    2011-01-01

    Bistable behavior of neuronal complex networks is investigated in the limited-sustained-activity regime when the network is composed of excitatory and inhibitory neurons. The standard stability analysis is performed on the two metastable states separately. Both theoretical analysis and numerical simulations show consistently that the difference between time scales of excitatory and inhibitory populations can influence the dynamical behaviors of the neuronal networks dramatically, leading to the transition from bistable behaviors with memory effects to the collapse of bistable behaviors. These results may suggest one possible neuronal information processing by only tuning time scales.

  8. Changes of Intramuscular Fat Composition, Lipid Oxidation and Lipase Activity in Biceps femoris and Semimembranosus of Xuanwei Ham During Controlled Salting Stages

    Institute of Scientific and Technical Information of China (English)

    WANG Zhen-yu; GAO Xiao-guang; ZHANG Ji-hong; ZHANG De-quan; MA Chang-wei

    2013-01-01

    Fatty acid composition of neutral lipids (NLs), phospholipids (PLs) and free fatty acids (FFAs) from intramuscular fat (IMF), lipid oxidation and lipase activity in muscle Semimembranosus (SM) and msucle Biceps femoris (BF) of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%(P<0.001) and 34.64%(P<0.05), furthermore, the saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM (from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids). The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances (TBARS) was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits.

  9. Organic Solvent Tolerant Lipases and Applications

    Directory of Open Access Journals (Sweden)

    Shivika Sharma

    2014-01-01

    Full Text Available Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s could be performed in water-restricted organic media as organic solvent(s not only improve(s the solubility of substrate and reactant in reaction mixture but also permit(s the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

  10. Acetylcholinesterase Inhibitory Activities of Flavonoids from the Leaves of Ginkgo biloba against Brown Planthopper

    Directory of Open Access Journals (Sweden)

    Xiao Ding

    2013-01-01

    Full Text Available Ginkgo biloba is a traditional Chinese medicinal plant which has potent insecticidal activity against brown planthopper. The MeOH extract was tested in the acetylcholinesterase (AChE inhibitory assay with IC50 values of 252.1 μg/mL. Two ginkgolides and thirteen flavonoids were isolated from the leaves of Ginkgo biloba. Their structures were established on the basis of spectroscopic data interpretation. It revealed that the 13 isolated flavonoids were found to inhibit AChE with IC50 values ranging from 57.8 to 133.1 μg/mL in the inhibitory assay. AChE was inhibited dose dependently by all tested flavonoids, and compound 6 displayed the highest inhibitory effect against AChE with IC50 values of 57.8 μg/mL.

  11. Synthesis and topoisomerase II inhibitory and cytotoxic activity of oxiranylmethoxy- and thiiranylmethoxy-chalcone derivatives.

    Science.gov (United States)

    Na, Younghwa; Nam, Jung-Min

    2011-01-01

    In order to find potential anticancer drug candidate targeting topoisomerases enzyme, we have designed and synthesized oxiranylmethoxy- and thiiranylmethoxy-retrochalcone derivatives and evaluated their pharmacological activity including topoisomerases inhibitory and cytotoxic activity. Of the compounds prepared compound 25 showed comparable or better cytotoxic activity against cancer cell lines tested. Compound 25 inhibited MCF7 (IC(50): 0.49 ± 0.21 μM) and HCT15 (IC(50): 0.23 ± 0.02 μM) carcinoma cell growth more efficiently than references. In the topoisomerases inhibition test, all the compounds were inactive to topoisomerase I but moderate inhibitors to topoisomerase II enzyme. Especially, compound 25 inhibited topoisomerase II activity with comparable extent to etoposide at 100 μM concentrations. Correlation between cytotoxicity and topoisomerase II inhibitory activity implies that compound 25 can be a possible lead compound for anticancer drug impeding the topoisomerase II function.

  12. Angiotensin I-Converting Enzyme (ACE Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    Directory of Open Access Journals (Sweden)

    Małgorzata Darewicz

    2014-08-01

    Full Text Available The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes and ex vivo digestion (with human gastrointestinal enzymes. Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50% of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  13. Crude Aloe vera Gel Shows Antioxidant Propensities and Inhibits Pancreatic Lipase and Glucose Movement In Vitro

    Directory of Open Access Journals (Sweden)

    Urmeela Taukoorah

    2016-01-01

    Full Text Available Aloe vera gel (AVG is traditionally used in the management of diabetes, obesity, and infectious diseases. The present study aimed to investigate the inhibitory potential of AVG against α-amylase, α-glucosidase, and pancreatic lipase activity in vitro. Enzyme kinetic studies using Michaelis-Menten (Km and Lineweaver-Burk equations were used to establish the type of inhibition. The antioxidant capacity of AVG was evaluated for its ferric reducing power, 2-diphenyl-2-picrylhydrazyl hydrate scavenging ability, nitric oxide scavenging power, and xanthine oxidase inhibitory activity. The glucose entrapment ability, antimicrobial activity, and total phenolic, flavonoid, tannin, and anthocyanin content were also determined. AVG showed a significantly higher percentage inhibition (85.56±0.91 of pancreatic lipase compared to Orlistat. AVG was found to increase the Michaelis-Menten constant and decreased the maximal velocity (Vmax of lipase, indicating mixed inhibition. AVG considerably inhibits glucose movement across dialysis tubes and was comparable to Arabic gum. AVG was ineffective against the tested microorganisms. Total phenolic and flavonoid contents were 66.06±1.14 (GAE/mg and 60.95±0.97 (RE/mg, respectively. AVG also showed interesting antioxidant properties. The biological activity observed in this study tends to validate some of the traditional claims of AVG as a functional food.

  14. Crude Aloe vera Gel Shows Antioxidant Propensities and Inhibits Pancreatic Lipase and Glucose Movement In Vitro

    Science.gov (United States)

    Taukoorah, Urmeela; Mahomoodally, M. Fawzi

    2016-01-01

    Aloe vera gel (AVG) is traditionally used in the management of diabetes, obesity, and infectious diseases. The present study aimed to investigate the inhibitory potential of AVG against α-amylase, α-glucosidase, and pancreatic lipase activity in vitro. Enzyme kinetic studies using Michaelis-Menten (K m) and Lineweaver-Burk equations were used to establish the type of inhibition. The antioxidant capacity of AVG was evaluated for its ferric reducing power, 2-diphenyl-2-picrylhydrazyl hydrate scavenging ability, nitric oxide scavenging power, and xanthine oxidase inhibitory activity. The glucose entrapment ability, antimicrobial activity, and total phenolic, flavonoid, tannin, and anthocyanin content were also determined. AVG showed a significantly higher percentage inhibition (85.56 ± 0.91) of pancreatic lipase compared to Orlistat. AVG was found to increase the Michaelis-Menten constant and decreased the maximal velocity (V max) of lipase, indicating mixed inhibition. AVG considerably inhibits glucose movement across dialysis tubes and was comparable to Arabic gum. AVG was ineffective against the tested microorganisms. Total phenolic and flavonoid contents were 66.06 ± 1.14 (GAE)/mg and 60.95 ± 0.97 (RE)/mg, respectively. AVG also showed interesting antioxidant properties. The biological activity observed in this study tends to validate some of the traditional claims of AVG as a functional food. PMID:26880905

  15. The Lid and Interfacial Activity of Lipases%脂肪酶活性部位上的盖与界面活性

    Institute of Scientific and Technical Information of China (English)

    解金兰; 丛方地

    2011-01-01

    Lipases are a kind of significant hydrolytic enzymes, which have significant application in some areas such as industrial production, medicine and scientific research. Most of lipases have a section of α-helix commonly named 'lid' over their active sites, which endow them with the special catalytic activity, interfacial activity, on the water/oil interface, but with low activity or without activity in pure water or oil. Because the interfacial activity is closely related to the lid composition, size, conformation and environment, it is very critical to make out the connection between lid and interfacial activity for development and utilization of lipases, and then the science problem on the role of lid playing in enzymatic catalysis has been unweariedly explored by biochemists for a long time. In this paper, we review the literatures on diverse lipase catalysis induced by lid conformational change, positional motion,compositional difference and artificial deletion, and expect that the review would help to understand the relation between the lid and the catalysis of lipases.%脂肪酶是一种非常重要的水解酶,在工业催化、医药和科学研究等领域中有广泛应用.大部分脂肪酶的活性部位上方有一段被称为"盖"的α-螺旋,这种盖赋予脂肪酶在水/油界面上有特殊的催化活性,界面活性.而在单一水相或油相中却表现出低活性或无活性.界面活性与盖的组成、大小、构象及其存在环境等密切相关,探明盖与脂肪酶界面活性的关系对于脂肪酶的开发和利用是非常关键的.因此,长期以来人们对盖在脂肪酶催化作用中所扮演的角色进行了孜孜不倦的探索.本文从盖的构象、移动、组成和删除等方面综述了其对脂肪酶催化作用的影响,期望对人们认识脂肪酶盖与其催化作用之间的关系有一定的帮助.

  16. Parvalbumin-Positive Inhibitory Interneurons Oppose Propagation But Favor Generation of Focal Epileptiform Activity.

    Science.gov (United States)

    Sessolo, Michele; Marcon, Iacopo; Bovetti, Serena; Losi, Gabriele; Cammarota, Mario; Ratto, Gian Michele; Fellin, Tommaso; Carmignoto, Giorgio

    2015-07-01

    Parvalbumin (Pv)-positive inhibitory interneurons effectively control network excitability, and their optogenetic activation has been reported to block epileptic seizures. An intense activity in GABAergic interneurons, including Pv interneurons, before seizures has been described in different experimental models of epilepsy, raising the hypothesis that an increased GABAergic inhibitory signal may, under certain conditions, initiate seizures. It is therefore unclear whether the activity of Pv interneurons enhances or opposes epileptiform activities. Here we use a mouse cortical slice model of focal epilepsy in which the epileptogenic focus can be identified and the role of Pv interneurons in the generation and propagation of seizure-like ictal events is accurately analyzed by a combination of optogenetic, electrophysiological, and imaging techniques. We found that a selective activation of Pv interneurons at the focus failed to block ictal generation and induced postinhibitory rebound spiking in pyramidal neurons, enhancing neuronal synchrony and promoting ictal generation. In contrast, a selective activation of Pv interneurons distant from the focus blocked ictal propagation and shortened ictal duration at the focus. We revealed that the reduced ictal duration was a direct consequence of the ictal propagation block, probably by preventing newly generated afterdischarges to travel backwards to the original focus of ictal initiation. Similar results were obtained upon individual Pv interneuron activation by intracellular depolarizing current pulses. The functional dichotomy of Pv interneurons here described opens new perspectives to our understanding of how local inhibitory circuits govern generation and spread of focal epileptiform activities.

  17. Lipases as Tools in the Synthesis of Prodrugs from Racemic 9-(2,3-Dihydroxypropyladenine

    Directory of Open Access Journals (Sweden)

    Marcela Krečmerová

    2012-11-01

    Full Text Available Lipases from Geotrichum candidum 4013 (extracellular lipase and cell-bound lipase were immobilized by adsorption on chitosan beads. The enzyme preparations were tested in the synthesis of ester prodrugs from racemic 9-(2,3-dihydroxypropyladenine in dimethylformamide with different vinyl esters (acetate, butyrate, decanoate, laurate, palmitate. The transesterification activities of these immobilized enzymes were compared with commercially available lipases (lipase from hog pancreas, Aspergillus niger, Candida antarctica, Pseudomonas fluorescens. Lipase from Candida antarctica was found to be the most efficient enzyme regarding chemical yield of the desired products, while transesterification by lipase from Aspergillus niger resulted in lower yields.

  18. Effects of insulin and exercise on muscle lipoprotein lipase activity in man and its relation to insulin action

    DEFF Research Database (Denmark)

    Kiens, Bente; Lithell, H; Mikines, K J;

    1989-01-01

    -induced increase in leg glucose uptake (r = 0.93, P less than 0.05). In the control group (n = 6) in which saline was infused in place of insulin and glucose, m-LPLA in nonexercised muscle did not change with time. No change in m-LPLA was observed immediately after one-legged knee extension exercise, but 4 h after......The effects of exercise and a physiological increase in plasma insulin concentration on muscle lipoprotein lipase activity (mLPLA), leg exchange of glucose, and serum lipoprotein levels were investigated in healthy young men. During euglycemic hyperinsulinemia (n = 7) at 44 mU.liter-1, m......-LPLA in non-exercised muscle decreased from 30 +/- 7.4 mU.g-1 wet weight (w.w.) (mean +/- SE) to 19 +/- 3.3 (P less than 0.05). Furthermore, the decrease in m-LPLA correlated closely (r = 0.97, P less than 0.05) with the increase in leg glucose uptake. Moreover, basal m-LPLA correlated with the insulin...

  19. X-ray structure of Candida antarctica lipase A shows a novel lid structure and a likely mode of interfacial activation.

    Science.gov (United States)

    Ericsson, Daniel J; Kasrayan, Alex; Johansson, Patrik; Bergfors, Terese; Sandström, Anders G; Bäckvall, Jan-E; Mowbray, Sherry L

    2008-02-08

    In nature, lipases (EC 3.1.1.3) catalyze the hydrolysis of triglycerides to form glycerol and fatty acids. Under the appropriate conditions, the reaction is reversible, and so biotechnological applications commonly make use of their capacity for esterification as well as for hydrolysis of a wide variety of compounds. In the present paper, we report the X-ray structure of lipase A from Candida antarctica, solved by single isomorphous replacement with anomalous scattering, and refined to 2.2-A resolution. The structure is the first from a novel family of lipases. Contrary to previous predictions, the fold includes a well-defined lid as well as a classic alpha/beta hydrolase domain. The catalytic triad is identified as Ser184, Asp334 and His366, which follow the sequential order considered to be characteristic of lipases; the serine lies within a typical nucleophilic elbow. Computer docking studies, as well as comparisons to related structures, place the carboxylate group of a fatty acid product near the serine nucleophile, with the long lipid tail closely following the path through the lid that is marked by a fortuitously bound molecule of polyethylene glycol. For an ester substrate to bind in an equivalent fashion, loop movements near Phe431 will be required, suggesting the primary focus of the conformational changes required for interfacial activation. Such movements will provide virtually unlimited access to solvent for the alcohol moiety of an ester substrate. The structure thus provides a basis for understanding the enzyme's preference for acyl moieties with long, straight tails, and for its highly promiscuous acceptance of widely different alcohol and amine moieties. An unconventional oxyanion hole is observed in the present structure, although the situation may change during interfacial activation.

  20. Inhibitory Effects of seco-Triterpenoids from Acanthopanax sessiliflorus Fruits on HUVEC Invasion and ACE Activity.

    Science.gov (United States)

    Lee, Jin-Won; Baek, Nam-In; Lee, Dae-Young

    2015-09-01

    This study was conducted to investigate the effects of the crude extract from Acanthopanax sessiliflorus fruits and the isolated seco-triterpenoids from the crude extract on blood flow in human umbilical vein endothelial cell (HUVEC) invasion assay and angiotensin converting enzyme (ACE) inhibitory activity assay. On the basis of DMSO, the extent of HUVECs' invasion was remarkably decreased with crude extract concentrations of 400 and 1000 pg/mL. Additionally, the extent of the HUVEC invasion inhibitory effect in 400 and 1000 µg/mL of acanthosessilioside F were 55.8% and 72.4%, respectively. In addition, the maximum extent of the HUVEC invasion inhibitory effect of 22-α-hydroxychiisanoside was 88.9%. The IC50 value of the inhibitory effect on ACE activity in the crude extract was 4 µg/mL. The isolated seco-triterpenoids, 22α-hydroxychiisanogenin, 3,4-seco-lupan-20(30)-en-3,28-dioic acid, (lR)-1,4-epoxy-11α,22α-hydroxy-3,4-seco-lupan-20(30)-en-3,28-dioicacid, (+)-divaroside, and chiisanosidehad showed very high inhibitory effects on ACE activity, ranging from 1.8 to 2.9 µg/mL, which is much higher than the 150.0 µg/mL effect of aspirin. These results suggest that the crude extract from Acanthopanax sessiliflorus fruits and the isolated seco-triterpenoids from the crude extract enhance the blood flow effect by decreasing ACE activity.

  1. In vivo hypotensive effect and in vitro inhibitory activity of some Cyperaceae species

    Directory of Open Access Journals (Sweden)

    Monica Lacerda Lopes Martins

    2013-12-01

    Full Text Available In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES, a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg, with acetylcholine (ACh as positive control (5 µg/kg, i.v.. The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.. Captopril (30 mg/kg was used as positive control. Bulbostylis capillaris (86.89 ± 15.20% and ERE (74.89 ± 11.95%, ERE were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%. ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.

  2. Hyaluronidase and collagenase inhibitory activities of the herbal formulation Triphala guggulu

    Indian Academy of Sciences (India)

    Venil N Sumantran; Asavari A Kulkarni; Abhay Harsulkar; Asmita Wele; Soumya J Koppikar; Rucha Chandwaskar; Vishakha Gaire; Madhuri Dalvi; Ulhas V Wagh

    2007-06-01

    Myrrh (guggulu) oleoresin from the Commiphora mukul tree is an important component of antiarthritic drugs in Ayurvedic medicine. Clinical data suggest that elevated levels of hyaluronidase and collagenase type 2 enzymes contribute significantly to cartilage degradation. Triphala guggulu (TG) is a guggulu-based formulation used for the treatment of arthritis. We assessed the chondroprotective potential of TG by examining its effects on the activities of pure hyaluronidase and collagenase type 2 enzymes. Triphala shodith guggulu (TSG), an intermediate in the production of TG, was also examined. A spectrophotometric method was used to assay Hyaluronidase activity, and to detect potential Hyaluronidase inhibitors. Aqueous and hydro-alcoholic extracts of TSG showed weak but dose-dependent inhibition of hyaluronidase activity. In contrast, the TG formulation was 50 times more potent than the TSG extract with respect to hyaluronidase inhibitory activity. A validated X-ray film-based assay was used to measure the gelatinase activity of pure collagenase type 2. Hydro-alcoholic extracts of the TG formulation were 4 times more potent than TSG with respect to collagenase inhibitory activity. Components of Triphala were also evaluated for their inhibitory activities on hyaluronidase and collagenase. This is the first report to show that the T2 component of Triphala (T. chebula) is a highly potent hyaluronidase and collagenase inhibitor. Thus, the TG formulation inhibits two major enzymes that can degrade cartilage matrix. Our study provides the first in vitro preclinical evidence of the chondroprotective properties of TG.

  3. In vitro anti-inflammatory and xanthine oxidase inhibitory activity of Tephrosia purpurea shoot extract.

    Science.gov (United States)

    Nile, Shivraj H; Khobragade, Chandrahasy N

    2011-10-01

    The methanolic extract of Tephrosia purpurea (Leguminosae) shoots was evaluated in-vitro for its anti-inflammatory and xanthine oxidase inhibitory activity. Anti-inflammatory activity was measured by the Diene-conjugate, HET-CAM and beta-glucuronidase methods. The enzyme inhibitory activity was tested against isolated cow milk xanthine oxidase. The average anti-inflammatory activity of T. purpurea shoot extract in the concentration range of 1-2 microg/mL in the reacting system revealed significant anti-inflammatory activities, which, as recorded by the Diene-conjugate, HET-CAM and beta-glucuronidase assay methods, were 45.4, 10.5, and 70.5%, respectively. Screening of the xanthine oxidase inhibitory activity of the extract in terms of kinetic parameters revealed a mixed type of inhibition, wherein the Km and Vmax values in the presence of 25 to 100 microg/mL shoot extract was 0.20 mM/mL and 0.035, 0.026, 0.023 and 0.020 microg/min, while, for the positive control, the Km and Vmax values were 0.21 mM/mL and 0.043 microg/min, respectively. These findings suggest that T. purpurea shoot extract may possess constituents with good medicinal properties that could be exploited to treat the diseases associated with oxidative stress, xanthine oxidase enzyme activity and inflammation.

  4. Pacemaker activity and inhibitory neurotransmission in the colon of Ws/Ws mutant rats

    DEFF Research Database (Denmark)

    Albertí, Elena; Mikkelsen, Hanne Birte; Wang, Xuanyu

    2007-01-01

    The aim of this study was to characterize the pacemaker activity and inhibitory neurotransmission in the colon of Ws/Ws mutant rats, which harbor a mutation in the c-kit gene that affects development of interstitial cells of Cajal (ICC). In Ws/Ws rats, the density of KIT-positive cells was marked...... as indirect innervation via ICC. In summary, loss of ICC markedly affects pacemaker and motor activities of the rat colon. Inhibitory innervation is largely maintained but nitrergic innervation is reduced possibly related to the loss of ICC-mediated relaxation.......The aim of this study was to characterize the pacemaker activity and inhibitory neurotransmission in the colon of Ws/Ws mutant rats, which harbor a mutation in the c-kit gene that affects development of interstitial cells of Cajal (ICC). In Ws/Ws rats, the density of KIT-positive cells was markedly...... of 10-20 cycles/min. Spontaneous activity of nitrergic nerves caused sustained inhibition of muscle activity in both wild-type (+/+) and Ws/Ws rats. Electrical field stimulation of enteric nerves, after blockade of cholinergic and adrenergic activity, elicited inhibition of mechanical activity...

  5. IMMOBILIZATION OF LIPASE FROM PORCINE PANCREAS ON POLY (METHYL ACRYLATE)COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    XuHuixian; LiMinqin; 等

    1994-01-01

    A series of poly(methyl acrylate) copolymers of different pore structures were synthesized and functionalized by polyethylene polyamine.The lipase from porcine pancreas was adsorbed on these polymer carriers. It was found that the proe structure and functional group were basic factors which affected the activity of immobilized lipase,The optimal conditions for adsorbing lipase were studied and the effects of pH,ionic strength and temperature on the immobilized lipase were compared with those on the dissolved lipase.

  6. Candida antarctica lipase B chemically immobilized on epoxy-activated micro- and nanobeads: catalysts for polyester synthesis.

    Science.gov (United States)

    Chen, Bo; Hu, Jun; Miller, Elizabeth M; Xie, Wenchun; Cai, Minmin; Gross, Richard A

    2008-02-01

    Candida antarctica Lipase B (CALB) was covalently immobilized onto epoxy-activated macroporous poly(methyl methacrylate) Amberzyme beads (235 microm particle size, 220 A pore size) and nanoparticles (nanoPSG, diameter 68 nm) with a poly(glycidyl methacrylate) outer region. Amberzyme beads allowed CALB loading up to 0.16 g of enzyme per gram of support. IR microspectroscopy generated images of Amberzyme-CALB beads showed CALB is localized within a 50 microm thick loading front. IR microspectroscopy images, recorded prior to and after treatment of Amberzyme-CALB with DMSO/aqueous Triton X-100, are similar, confirming that CALB is largely chemically linked to Amberzyme. The activity of CALB immobilized on Amberzyme, Lewatit (i.e., Novozym 435 catalyst), and nanoPSG was assessed for lactone ring-opening and step-condensation polymerizations. For example, the percent conversion of -caprolactone using the same amount of enzyme catalyzed by Amberzym-CALB, Novozym 435, and nanoPSG-CALB for 20 min was 7.0, 16, and 65%, respectively. Differences in CALB reactivity were discussed based on resin physical parameters and availability of active sites determined by active site titrations. Regardless of the matrix used and chemical versus physical immobilization, -CL ring-opening polymerizations occur by a chain growth mechanism without chain termination. To test Amberzyme-CALB stability, the catalyst was reused over three reaction cycles for -CL ring-opening polymerization (70 degrees C, 70 min reactions) and glycerol/1,8-octanediol/adipic acid polycondensation reactions (90 degrees C, 64 h). Amberzyme-CALB was found to have far better stability for reuse relative to Novozym 435 for the polycondensation reaction.

  7. G0/G1 Switch Gene 2 controls adipose triglyceride lipase activity and lipid metabolism in skeletal muscle.

    Science.gov (United States)

    Laurens, Claire; Badin, Pierre-Marie; Louche, Katie; Mairal, Aline; Tavernier, Geneviève; Marette, André; Tremblay, Angelo; Weisnagel, S John; Joanisse, Denis R; Langin, Dominique; Bourlier, Virginie; Moro, Cedric

    2016-07-01

    Recent data suggest that adipose triglyceride lipase (ATGL) plays a key role in providing energy substrate from triglyceride pools and that alterations of its expression/activity relate to metabolic disturbances in skeletal muscle. Yet little is known about its regulation. We here investigated the role of the protein G0/G1 Switch Gene 2 (G0S2), recently described as an inhibitor of ATGL in white adipose tissue, in the regulation of lipolysis and oxidative metabolism in skeletal muscle. We first examined G0S2 protein expression in relation to metabolic status and muscle characteristics in humans. We next overexpressed and knocked down G0S2 in human primary myotubes to assess its impact on ATGL activity, lipid turnover and oxidative metabolism, and further knocked down G0S2 in vivo in mouse skeletal muscle. G0S2 protein is increased in skeletal muscle of endurance-trained individuals and correlates with markers of oxidative capacity and lipid content. Recombinant G0S2 protein inhibits ATGL activity by about 40% in lysates of mouse and human skeletal muscle. G0S2 overexpression augments (+49%, p lipolysis and fatty acid oxidation in a strictly ATGL-dependent manner. These metabolic adaptations mediated by G0S2 are paralleled by concomitant changes in glucose metabolism through the modulation of Pyruvate Dehydrogenase Kinase 4 (PDK4) expression (5.4 fold, p < 0.001). Importantly, downregulation of G0S2 in vivo in mouse skeletal muscle recapitulates changes in lipid metabolism observed in vitro. Collectively, these data indicate that G0S2 plays a key role in the regulation of skeletal muscle ATGL activity, lipid content and oxidative metabolism.

  8. Effects of Porous Polystyrene Resin Parameters on Candida antarctica Lipase B Adsorption, Distribution, and Polyester Synthesis Activity

    Energy Technology Data Exchange (ETDEWEB)

    Chen,B.; Miller, M.; Gross, R.

    2007-01-01

    Polystyrene resins with varied particle sizes (35 to 350-600 {mu}m) and pore diameters (300-1000 {angstrom}) were employed to study the effects of immobilization resin particle size and pore diameter on Candida antarctica Lipase B (CALB) loading, distribution within resins, fraction of active sites, and catalytic properties for polyester synthesis. CALB adsorbed rapidly (saturation time {<=}4 min) for particle sizes 120 {mu}m (pore size = 300 {angstrom}). Infrared microspectroscopy showed that CALB forms protein loading fronts regardless of resin particle size at similar enzyme loadings ({approx}8%). From the IR images, the fractions of total surface area available to the enzyme are 21, 33, 35, 37, and 88% for particle sizes 350-600, 120, 75, 35 {mu}m (pore size 300 {angstrom}), and 35 {mu}m (pore size 1000 {angstrom}), respectively. Titration with methyl p-nitrophenyl n-hexylphosphate (MNPHP) showed that the fraction of active CALB molecules adsorbed onto resins was {approx}60%. The fraction of active CALB molecules was invariable as a function of resin particle and pore size. At {approx}8% (w/w) CALB loading, by increasing the immobilization support pore diameter from 300 to 1000 {angstrom}, the turnover frequency (TOF) of {var_epsilon}-caprolactone ({var_epsilon}-CL) to polyester increased from 12.4 to 28.2 s{sup -1}. However, the {var_epsilon}-CL conversion rate was not influenced by changes in resin particle size. Similar trends were observed for condensation polymerizations between 1,8-octanediol and adipic acid. The results herein are compared to those obtained with a similar series of methyl methacrylate resins, where variations in particle size largely affected CALB distribution within resins and catalyst activity for polyester synthesis.

  9. Candida antarctica Lipase B Chemically Immobilized on Epoxy-Activate Micro- and Nanobeads: Catalysts for Polyester Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Chen,B.; Hu, J.; Miller, E.; Xie, W.; Cai, M.; Gross, R.

    2008-01-01

    Candida antarctica Lipase B (CALB) was covalently immobilized onto epoxy-activated macroporous poly(methyl methacrylate) Amberzyme beads (235 {mu}m particle size, 220 Angstroms pore size) and nanoparticles (nanoPSG, diameter 68 nm) with a poly(glycidyl methacrylate) outer region. Amberzyme beads allowed CALB loading up to 0.16 g of enzyme per gram of support. IR microspectroscopy generated images of Amberzyme-CALB beads showed CALB is localized within a 50 {mu}m thick loading front. IR microspectroscopy images, recorded prior to and after treatment of Amberzyme-CALB with DMSO/aqueous Triton X-100, are similar, confirming that CALB is largely chemically linked to Amberzyme. The activity of CALB immobilized on Amberzyme, Lewatit (i.e., Novozym 435 catalyst), and nanoPSG was assessed for lactone ring-opening and step-condensation polymerizations. For example, the percent conversion of -caprolactone using the same amount of enzyme catalyzed by Amberzym-CALB, Novozym 435, and nanoPSG-CALB for 20 min was 7.0, 16, and 65%, respectively. Differences in CALB reactivity were discussed based on resin physical parameters and availability of active sites determined by active site titrations. Regardless of the matrix used and chemical versus physical immobilization, -CL ring-opening polymerizations occur by a chain growth mechanism without chain termination. To test Amberzyme-CALB stability, the catalyst was reused over three reaction cycles for -CL ring-opening polymerization (70 C, 70 min reactions) and glycerol/1, 8-octanediol/adipic acid polycondensation reactions (90 C, 64 h). Amberzyme-CALB was found to have far better stability for reuse relative to Novozym 435 for the polycondensation reaction.

  10. Extracts of Edible Plants Inhibit Pancreatic Lipase, Cholesterol Esterase and Cholesterol Micellization, and Bind Bile Acids

    Directory of Open Access Journals (Sweden)

    Julnaryn Intrawangso

    2012-01-01

    Full Text Available The application of edible plants with more effective ability to inhibit fat digestion and absorption has recently been explored for possible treatment of hyperlipidaemia. The aim of the present study is to investigate the effect of nine edible plants on the inhibition of pancreatic lipase and pancreatic cholesterol esterase activities, as well as the inhibition of cholesterol micelle formation, and bile acid binding. Our findings have shown strong pancreatic lipase inhibitory activity and the inhibition of cholesterol micellization by mulberry leaf extract. Safflower extract was the most potent inhibitor of pancreatic cholesterol esterase. In addition, cat’s whiskers and safflower extracts had a potent bile acid binding activity. It is suggested that a daily intake of these edible plants may delay postprandial hypertriacylglycerolaemia and hypercholesterolaemia, and therefore may be applied for the prevention and treatment of hyperlipidaemia.

  11. Telomerase inhibitory effects of medicinal mushrooms and lichens, and their anticancer activity.

    Science.gov (United States)

    Xu, Baojun; Li, Chantian; Sung, Changkeun

    2014-01-01

    Telomerase has been widely accepted as a cancer marker and a promising therapeutic target for novel anticancer drugs. The aim of this study was to investigate the in vitro telomerase inhibitory effects of mushrooms and their anticancer properties. The inhibitory effects of mushrooms and lichens against telomerase activity of HL-60 cells were systematically assessed using polymerase chain reaction based on assay of telomeric repeat amplification protocol. Telomerase inhibitory samples were further tested for antiproliferation effects against the gastric cell line SNU-1 using the MTT method. Ethyl acetate extract of Pleurotus ostreatus, ethyl acetate and water extracts of Lasiosphaera fenzlii, hexane extract of Strobilomyces floccopus, water extract of Sarcodon aspratus, and hexane, ethyl acetate, and water extracts from Umbilicaria esculenta showed strong positive telomerase inhibitory activity. Hexane extract of S. floccopus and water extracts from the edible lichen U. esculenta exhibited strong anticancer effects against SNU-1 cells through antiproliferation assay. The water extract of U. esculenta has a great potential to be developed into an anticancer agent that targets telomerase.

  12. Benzophenones from Mango Leaves Exhibit α-Glucosidase and NO Inhibitory Activities.

    Science.gov (United States)

    Pan, Jing; Yi, Xiaomin; Wang, Yihai; Chen, Guisi; He, Xiangjiu

    2016-10-12

    Mango (Mangifera indica L.) is a succulent tropical fruit. Bioactive phytochemical investigation has been carried out to the leaves of mango. Three new benzophenone glycosides, along with 14 known compounds, were purified and identified. The novel benzophenones were elucidated to be 2,4,4',6-tetrahydroxy-3'-methoxybenzophenone-3-C-β-d-glucopyranoside (1), 4,4',6-trihydroxybenzophenone-2-O-α-l-arabinofuranoside (7), and 4',6-dihydroxy-4-methoxybenzophenone-2-O-(2″),3-C-(1″)-1″-desoxy-α-l-fructofuranoside (11). The α-glucosidase inhibitory, NO production inhibitory, and antioxidant activities were assessed for the purified benzophenones and triterpenoids. Some benzophenones showed moderate α-glucosidase and NO inhibitory activities. The IC50 value of the α-glucosidase inhibitory of isolated compounds 1, 13, and 14 were 284.93 ± 20.29, 239.60 ± 25.00, and 297.37 ± 8.12 μM, respectively. Most compounds showed moderate effects to reduce the NO content in 50 and 100 μM. The above results of bioactivity powerfully demonstrated the phytochemicals from mango, especially benzophenones, probably partially rational for its antidiabetes and anti-inflammatory.

  13. Inhibitory activity of phosphates on molds isolated from foods and food processing plants.

    Science.gov (United States)

    Suárez, V B; Frisón, L; de Basílico, M Z; Rivera, M; Reinheimer, J A

    2005-11-01

    Six commercial phosphates were evaluated for inhibition of the growth of 17 molds isolated from food sources. The assays were performed at neutral and natural (without pH adjustment) pH values, and the molds were streaked on plate count agar with added phosphates. Phosphate concentrations of 0.1, 0.3, 0.5, 1.0, and 1.5% (wt/vol) were used, and the MIC was determined. The resistance of molds to phosphates depended on the species. At a neutral pH, Aspergillus ochraceus and Fusarium proliferatum were resistant to all phosphates at all concentrations assayed, and Byssochlamys nivea, Aureobasidium pullulans, and Penicillium glabrum were most sensitive. The most inhibitory phosphates were those with chain lengths greater than 15 phosphate units and the highest sequestering power. At natural pH values (resulting from dissolving the phosphate in the medium), inhibitory activity changed dramatically for phosphates that produced alkaline or acidic pH in the medium. Phosphates with alkaline pH values (sodium tripolyphosphate of high solubility, sodium tripolyphosphate, and sodium neutral pyrophosphate) were much more inhibitory than phosphates at a neutral pH, but sodium acid pyrophosphate (acidic pH) had decreased inhibitory activity. The results indicate that some phosphates could be used in the food industry to inhibit molds linked to food spoilage.

  14. Phenol content, antioxidant and tyrosinase inhibitory activity of mangrove plants in Micronesia

    Institute of Scientific and Technical Information of China (English)

    Sung-Suk Suh; Jinik Hwang; Mirye Park; Heung-Sik Park; Taek-Kyun Lee

    2014-01-01

    Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island ofWeno,ChuukState inMicronesia.The phenol content, antioxidant activity(based onDPPH-free radical scavenging) and tyrosinase inhibitory activity in different tissues(leaves, barks and roots) ofRhizophora stylosa (R. stylosa) andSonneratia alba (S. alba), collected from the island ofWeno.Results:Total phenol content ranged from4.87 to11.96 mg per g of freeze dried samples.The highest antioxidant activity was observed inR. stylosa bark(85.5%).The highest tyrosinase inhibitory activity was found inS. alba bark.Also, total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts.Conclusions:Taken together, the results of this study proved that mangroves can be excellent sources of antioxidant compounds.

  15. Cytochrome P450-inhibitory activity of parabens and phthalates used in consumer products.

    Science.gov (United States)

    Ozaki, Hitomi; Sugihara, Kazumi; Watanabe, Yoko; Ohta, Shigeru; Kitamura, Shigeyuki

    2016-01-01

    The in vitro cytochrome P450 (CYP)-inhibitory effects of 11 parabens and 7 phthalates used in consumer products, as well as their hydrolytic metabolites, were investigated, using rat liver microsomes as an enzyme source. The effects on individual CYP isozymes were evaluated by assaying inhibition of activities towards specific substrates, i.e., ethoxyresorufin O-dealkylase (EROD), methoxyresorufin O-dealkylase (MROD), pentoxyresorufin O-dealkylase (PROD), 7-benzyloxy-4-trifluoromethylcoumarin dealkylase (BFCD), 7-methoxy-4-trifluoromethylcoumarin dealkylase (MFCD) and 7-ethoxy-4-trifluoromethylcoumarin dealkylase (EFCD) activities. These activities were dose-dependently inhibited, most potently by medium-side-chain parabens (C6-9) and phthalates (C4-6), and less potently by shorter- and longer-side-chain esters. The hydrolytic product of parabens, 4-hydroxybenzoic acid, was not inhibitory, while those of phthalates, phthalic acid monoesters, showed lower inhibitory activity than the parent phthalates. Parabens showed relatively potent inhibition of MFCD activity, considered to be mainly due to CYP2C, and phthalates showed relatively potent inhibition of PROD activity, considered to be mainly due to CYP2B.

  16. Chemical Composition and Enzymes Inhibitory, Brine Shrimp Larvae Toxicity, Antimicrobial and Antioxidant Activities of Caloplaca biatorina

    Directory of Open Access Journals (Sweden)

    Tahereh Valadbeigi

    2016-10-01

    Full Text Available Background This study evaluated the brine shrimp larvae toxicity and enzymes inhibitory especially anti-diabetic potential of Caloplaca biatorina via in vitro inhibition of α-amylase and α-glucosidase using the methanol extracts. Also aldehyde oxidase and xanthine oxidase enzymes inhibitory, cytotoxicity, and antioxidant activities of the species were determined. Methods In this experimental study, different concentrations of the extracts (0.2, 5.0, 1 and 1.5 mg/mL were incubated with enzyme substrate solution and the percentage of enzyme inhibitory activity and IC50 was calculated. Folin- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of extracts. The toxicity of the extract was assessed using the brine shrimp lethality bioassay. The minimal inhibitory concentration (MIC and minimum bactericidal concentration (MBC were determined. High-performance liquid chromatography and Thin-layer chromatography analysis were evaluated. The data were analyzed by SPSS V.21 software. Results Parietin, Emodin, 1,8-Dihydroxy-3-(hydroxymethyl-6- methoxy-9.10-anthracenedione and Rhein were identified. The extract showed strong α-glucosidase, aldehyde oxidase and xanthine oxidase inhibitory activities with IC50 value of 17.12, 40.09 and 11.02 µg/mL respectively. Also methanol extract displayed the strongest DPPH radical scavenging and brine shrimp toxicity (IC50 = 91.11 properties. Conclusions The result obtained suggests that the C. biatorina extract can be classified as non-toxic. Also, it revealed the antioxidant and antidiabetic potential of the lichen.

  17. Effect of sugar positions in ginsenosides and their inhibitory potency on Na+/K+-ATPase activity

    Institute of Scientific and Technical Information of China (English)

    Ronald JY CHEN; Tse-yu CHUNG; Feng-yin LI; Nan-hei LIN; Jason TC TZEN

    2009-01-01

    Aim: To determine whether ginsenosides with various sugar attachments may act as active components responsible for the cardiac therapeutic effects of ginseng and sanqi (the roots of Panax ginseng and Panax notoginseng) via the same molecular mechanism triggered by cardiac glycosides, such as ouabain and digoxin. Methods: The structural similarity between ginsenosides and ouabain was analyzed. The inhibitory potency of ginseno-sides and ouabain on Na+/K+-ATPase activity was examined and compared. Molecular modeling was exhibited for the docking of ginsenosides to Na+/K+-ATPase. Results: Ginsenosides with sugar moieties attached only to the C-3 position of the steroid-like structure, equivalent to the sugar position in cardiac glycosides, and possessed inhibitory potency on Na+/K+-ATPase activity. However, their inhibi-tory potency was significantly reduced or completely abolished when a monosaccharide was linked to the C-6 or C-20 posi-tion of the steroid-like structure; replacement of the monosaccharide with a disaccharide molecule at either of these posi-tions caused the disappearance of the inhibitory potency. Molecular modeling and docking confirmed that the difference in Na+/K+-ATPase inhibitory potency among ginsenosides was due to the steric hindrance of sugar attachment at the C-6 and C-20 positions of the steroid-like structure. Conclusion: The cardiac therapeutic effects of ginseng and sanqi should be at least partly attributed to the effective inhi-bition of Na+/K+-ATPase by their metabolized ginsenosides with sugar moieties attached only to the C-3 position of the steroid-like structure.

  18. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents

    DEFF Research Database (Denmark)

    Domazet, Sidsel L; Tarp, Jakob; Huang, Tao

    2016-01-01

    OBJECTIVES: To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. METHODS: The design was cross-sectional. A convenient sample of 869 sixth and seventh grade...... students (12-14 years) was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical...

  19. α-GLUCOSIDASE AND α -AMYLASE INHIBITORY ACTIVITIES OF RAPHANUS SATIVUS LINN.

    Directory of Open Access Journals (Sweden)

    R. Vadivelan et al

    2012-09-01

    Full Text Available Herbal medicine has been used for many years by different cultures around the world for the treatment of diabetes. There has been an enormous interest in the development of alternative medicines for type 2 diabetes, specifically screening for phytochemicals with the ability to delay or prevent glucose absorption. The goal of the present study is to evaluate the invitro antidiabetic activity of Raphanus sativus ethanolic extract and fractions by α-glucosidase and α -amylase inhibitory activity. Raphanus sativus ethanolic extract and fractions showed dose dependent inhibition of α-glucosidase and α -amylase enzyme and exhibited lower inhibitory activity than acarbose. The study revealed the antidiabetic potential and could be helpful to develop medicinal preparations and nutraceuticals and function foods for diabetes.

  20. Inhibitory effect of vanillin on cellulase activity in hydrolysis of cellulosic biomass.

    Science.gov (United States)

    Li, Yun; Qi, Benkun; Wan, Yinhua

    2014-09-01

    Pretreatment of lignocellulosic material produces a wide variety of inhibitory compounds, which strongly inhibit the following enzymatic hydrolysis of cellulosic biomass. Vanillin is a kind of phenolics derived from degradation of lignin. The effect of vanillin on cellulase activity for the hydrolysis of cellulose was investigated in detail. The results clearly showed that vanillin can reversibly and non-competitively inhibit the cellulase activity at appropriate concentrations and the value of IC50 was estimated to be 30 g/L. The inhibition kinetics of cellulase by vanillin was studied using HCH-1 model and inhibition constants were determined. Moreover, investigation of three compounds with similar structure of vanillin on cellulase activity demonstrated that aldehyde group and phenolic hydroxyl groups of vanillin had inhibitory effect on cellulase. These results provide valuable and detailed information for understanding the inhibition of lignin derived phenolics on cellulase.

  1. A competitive inhibitory circuit for selection of active and passive fear responses.

    Science.gov (United States)

    Fadok, Jonathan P; Krabbe, Sabine; Markovic, Milica; Courtin, Julien; Xu, Chun; Massi, Lema; Botta, Paolo; Bylund, Kristine; Müller, Christian; Kovacevic, Aleksandar; Tovote, Philip; Lüthi, Andreas

    2017-02-02

    When faced with threat, the survival of an organism is contingent upon the selection of appropriate active or passive behavioural responses. Freezing is an evolutionarily conserved passive fear response that has been used extensively to study the neuronal mechanisms of fear and fear conditioning in rodents. However, rodents also exhibit active responses such as flight under natural conditions. The central amygdala (CEA) is a forebrain structure vital for the acquisition and expression of conditioned fear responses, and the role of specific neuronal sub-populations of the CEA in freezing behaviour is well-established. Whether the CEA is also involved in flight behaviour, and how neuronal circuits for active and passive fear behaviour interact within the CEA, are not yet understood. Here, using in vivo optogenetics and extracellular recordings of identified cell types in a behavioural model in which mice switch between conditioned freezing and flight, we show that active and passive fear responses are mediated by distinct and mutually inhibitory CEA neurons. Cells expressing corticotropin-releasing factor (CRF(+)) mediate conditioned flight, and activation of somatostatin-positive (SOM(+)) neurons initiates passive freezing behaviour. Moreover, we find that the balance between conditioned flight and freezing behaviour is regulated by means of local inhibitory connections between CRF(+) and SOM(+) neurons, indicating that the selection of appropriate behavioural responses to threat is based on competitive interactions between two defined populations of inhibitory neurons, a circuit motif allowing for rapid and flexible action selection.

  2. Metabolism and growth inhibitory activity of cranberry derived flavonoids in bladder cancer cells.

    Science.gov (United States)

    Prasain, Jeevan K; Rajbhandari, Rajani; Keeton, Adam B; Piazza, Gary A; Barnes, Stephen

    2016-09-14

    In the present study, anti-proliferative activities of cranberry derived flavonoids and some of their in vivo metabolites were evaluated using a panel of human bladder tumor cell lines (RT4, SCABER, and SW-780) and non-tumorigenic immortalized human uroepithelial cells (SV-HUC). Among the compounds tested, quercetin 3-O-glucoside, isorhamnetin (3'-O-methylquercetin), myricetin and quercetin showed strong concentration-dependent cell growth inhibitory activities in bladder cancer cells with IC50 values in a range of 8-92 μM. Furthermore, isorhamnetin and myricetin had very low inhibitory activity against SV-HUC even at very high concentrations (>200 μM) compared to bladder cancer cells, indicating that their cytotoxicity is selective for cancer cells. To determine whether the differential cell growth inhibitory effects of isomeric flavonoids quercetin 3-O-glucoside (active) and hyperoside (quercetin 3-O-galactoside) (inactive) are related to their metabolism by the cancer cells, SW-780 cells were incubated with these compounds and their metabolism was examined by LC-MS/MS. Compared to quercetin 3-O-glucoside, hyperoside undergoes relatively less metabolic biotransformation (methylation, glucuronidation and quinone formation). These data suggest that isorhamnetin and quercetin 3-O-glucoside may be the active forms of quercetin in prevention of bladder cancer in vivo and emphasize the importance of metabolism for the prevention of bladder cancer by diets rich in cranberries.

  3. Inhibitory effects of active fraction and its main components of Shaofu Zhuyu decoction on uterus contraction.

    Science.gov (United States)

    Su, Shulan; Hua, Yongqing; Duan, Jin-Ao; Zhou, Wei; Shang, Erxin; Tang, Yuping

    2010-01-01

    Shaofu Zhuyu decoction is a famous formula for treating primary dysmenorrhea in China since the Qing dynasty. In this paper, the inhibitory effects of active-guided fraction and its main bioactive components of Shaofu Zhuyu decoction on a model of non-pregnant mice uterine contraction induced by oxytocin in vitro were investigated. Qualitative and quantitative chemical analyses were used to correlate the chemical composition of active fraction with the spasmolytic effects. Seven ingredients in the active fraction were identified and quantified by HPLC-DAD. Three ingredients, ferulic acid, vanillic acid, and typhaneoside, were evaluated for their effects on mice isolated uterine contraction induced by oxytocin in vitro. The ED(50) of them were 63.0 microg/ml, 57.6 microg/ml, 109.7 microg/ml, respectively. Furthermore, the inhibitory activity of the combination of these three compounds was prior to the fraction and seven compounds group. The ED(50) was 65.5 microg/ml. The data stated that ferulic acid, vanillic acid, and typhaneoside were possibly the main active components in the bioactive fraction of Shaofu Zhuyu decoction. The study also implied that Shaofu Zhuyu decoction may have direct inhibitory effects on the contractility of the mice uterus and justified the traditional use of the prescription for treating the uterine cramping associated dysmenorrhea.

  4. Developmental changes in adipose and muscle lipoprotein lipase activity in the atherosclerosis-prone JCR:LA-corpulent rat.

    Science.gov (United States)

    Mantha, L; Russell, J C; Brindley, D N; Deshaies, Y

    2002-03-01

    To characterize the developmental changes in adipose and muscle lipoprotein lipase (LPL) activity in the atherosclerosis-prone JCR:LA-corpulent rat, and to test the hypothesis that tissue-specific abnormalities in LPL activity precede the establishment of obesity. Lean (+/?) and obese cp/cp male JCR:LA rats were studied at 4, 5 and 8 weeks of age, that is at the onset of obesity, and at a time when obesity is well established. Assessment was made of plasma variables related to glucose and lipid metabolism and of LPL activity in several adipose depots, skeletal muscles and the heart. At week 4, body weights were identical in both genotypes and began to diverge at week 5. Eight-week-old cp/cp rats weighed 35% more than their lean counterparts. Perirenal and epididymal adipose depot weights were also identical in both genotypes at week 4 and began to increase in cp/cp rats at week 5, whereas the subcutaneous depot of 4-week-old cp/cp rats was slightly enlarged. At week 4, the cp/cp rats were hyperinsulinemic (5-fold), hyperleptinemic (30-fold) and hypertriglyceridemic (3-fold) compared to their lean counterparts, and their liver contained twice as much triglyceride. The 4-week-old cp/cp rats displayed 2-7-fold higher LPL specific activity in the various adipose depots compared to lean rats, and enzyme activity remained higher in obese than in lean rats at all subsequent ages. In contrast, LPL activity in the vastus lateralis, gastrocnemius and heart muscles of 4-week-old obese rats was approximately half that observed in lean animals. Profound, persistent alterations in the tissue-specific modulation of LPL activity are established in the JCR:LA cp/cp rat prior to the development of frank obesity. The increase in adipose tissue LPL activity and its decrease in muscle tissues are likely to be related to the concomitant alterations in insulinemia and triglyceridemia, respectively. The pre-obesity, tissue-specific alterations in LPL activity may be considered as an

  5. Inhibitory activity in vitro of probiotic lactobacilli against oral Candida under different fermentation conditions.

    Science.gov (United States)

    Jiang, Q; Stamatova, I; Kari, K; Meurman, J H

    2015-01-01

    Clinical studies have shown that probiotics positively affect oral health by decreasing gum bleeding and/or reducing salivary counts of certain oral pathogens. Our aim was to investigate the inhibitory effect of six probiotic lactobacilli against opportunistic oral Candida species. Sugar utilisation by both lactobacilli and Candida was also assessed. Agar overlay assay was utilised to study growth inhibition of Candida albicans, Candida glabrata and Candida krusei by Lactobacillus rhamnosus GG, Lactobacillus casei Shirota, Lactobacillus reuteri SD2112, Lactobacillus brevis CD2, Lactobacillus bulgaricus LB86 and L. bulgaricus LB Lact. The inhibitory effect was measured at pH 5.5, 6.4, and 7.2, respectively, and in the presence of five different carbohydrates in growth medium (glucose, fructose, lactose, sucrose, and sorbitol). Growth and final pH values were measured at two-hour time points to 24 h. L. rhamnosus GG showed the strongest inhibitory activity in fructose and glucose medium against C. albicans, followed by L. casei Shirota, L. reuteri SD2112 and L. brevis CD2. None of the lactobacilli tested affected the growth of C. krusei. Only L. rhamnosus GG produced slight inhibitory effect on C. glabrata. The lower pH values led to larger inhibition zones. Sugar fermentation profiles varied between the strains. L. casei Shirota grew in the presence of all sugars tested, whereas L. brevis CD2 could utilise only glucose and fructose. All Candida species metabolised the available sugars but the most rapid growth was observed with C. glabrata. The results suggest that commercially available probiotics differ in their inhibitory activity and carbohydrate utilisation; the above properties are modified by different pH values and sugars with more pronounced inhibition at lower pH.

  6. Improvement of the activation of lipase from Candida rugosa following physical and chemical immobilization on modified mesoporous silica.

    Science.gov (United States)

    Wang, Chunfeng; Li, Yanjing; Zhou, Guowei; Jiang, Xiaojie; Xu, Yunqiang; Bu, Zhaosheng

    2014-12-01

    Lipase from Candida rugosa (CRL) was chemically and physically immobilized onto four types of rod-shaped mesoporous silica (RSMS). RSMS prepared using surfactant P123 and poly(ethylene glycol) as co-templates was functionalized with (3-aminopropyl)triethoxysilane (APTES) to obtain P-RSMS by post-synthesis grafting. Tetraethoxysilane was hydrothermally co-condensed with APTES to obtain C-RSMS. A two-step process using APTES and glutaraldehyde was also performed to obtain G-RSMS. The effects of modification methods (including post-synthesis grafting and co-condensation) and glutaraldehyde on the mesoscopic order, interplanar spacing d100, cell parameter a0, mesoporous structure, and wall thickness of RSMS were studied in detail. Results showed that all samples were mesoporous materials with 2D mesostructures (p6mm). Pore size and d100 decreased, whereas the wall thickness increased after different modifications. CRL was used as a model enzyme to determine the effect of physical and chemical adsorption on loading amount and enzymatic activity. The possible mechanism of CRL immobilization on G-RSMS by chemical adsorption was systematically investigated. The chemical immobilization of CRL on G-RSMS increased the loading amount, hydrolytic activity, thermal stability, and reusability. Moreover, immobilized CRL was employed to catalyze the resolution of 2-octanol by esterification with caprylic acid. The enantiomeric excess of 2-octanol was 45.8% when the reaction was catalyzed by G-RSMS-CRL and decreased to about 38%-39% using the physically immobilized CRL, after 48 h of reaction in hexane. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Fasting-induced increases in aquaporin 7 and adipose triglyceride lipase mRNA expression in adipose tissue are attenuated by peroxisome proliferator-activated receptor alpha deficiency.

    Science.gov (United States)

    Walker, C G; Holness, M J; Gibbons, G F; Sugden, M C

    2007-07-01

    To investigate the impact of peroxisome proliferator-activated receptor alpha deficiency on gene expression of adipose triglyceride lipase and the glycerol transporter aquaglyceroporin 7 in white adipose tissue in the fed and fasted states in relation to glycerol release by isolated adipocytes. Studies using wild-type and peroxisome proliferator-activated receptor alpha null mice. Hormone and metabolite concentrations, real-time polymerase chain reaction (PCR), basal and stimulated adipocyte lipolysis, estimated by glycerol release. Peroxisome proliferator-activated receptor alpha deficiency blocked the increase in aquaglyceroporin 7 transcript level and attenuated the increase in adipose triglyceride lipase transcript level in white adipose tissue elicited by fasting. Fasting glycerol levels were lower in peroxisome proliferator-activated receptor alpha null than wild-type mice, despite increased mobilization of adipocyte fat reserves in vivo as indicated by reduced adipose tissue masses (three distinct depots) and a significantly lower epididymal adipocyte diameter. Basal net glycerol release was unchanged but beta-adrenergic-stimulated net glycerol release was higher with isolated adipocytes from fasted peroxisome proliferator-activated receptor alpha null mice compared with those of fasted wild-type mice. Peroxisome proliferator-activated receptor alpha deficiency prevents effects of fasting to increase adipocyte aquaglyceroporin 7 gene expression, and influences the regulation of inter-tissue glycerol flux after fasting via lowered adipocyte aquaglyceroporin 7 expression. Lowered gene expression of adipose triglyceride lipase and aquaglyceroporin 7 in peroxisome proliferator-activated receptor alpha null mice is not limiting for adipose triglyceride breakdown in vivo during fasting.

  8. In Vitro Antioxidant and Enzymes Inhibitory activity of Chloroform Fraction of Hydroalcoholic extract obtained from Argemone mexicana

    Directory of Open Access Journals (Sweden)

    Nayak P

    2013-03-01

    Full Text Available In the present investigation antioxidant and alphaamylase inhibitory activity of chloroform fraction of Argemone mexicana were evaluated. The antioxidant activity of chloroform fraction of A. mexicana was evaluated by DPPH, Super oxide radical Scavenging activity, ABTS radical cation scavenging activity and Nitric oxide radical scavenging activity. Alpha-amylase inhibitory activity of chloroform fraction was evaluated by DNS method respectively. The observed resultant antioxidant activity of chloroform fraction in all studied models was moderate as compared with reference standard Ascorbic acid. The chloroform fraction exhibited appreciable α-amylase inhibitory activity with an IC50 value 48.92μg/ml respectively, when compared with acarbose (IC50 value 83.33μg/ml.In conclusion, from the results of present study it is confirmed that antioxidant and alpha-amylase inhibitory activity of chloroform fraction of A. mexicana may contribute in its earlier observed antidiabetic potential.

  9. Patterns of brain activation in foster children and nonmaltreated children during an inhibitory control task.

    Science.gov (United States)

    Bruce, Jacqueline; Fisher, Philip A; Graham, Alice M; Moore, William E; Peake, Shannon J; Mannering, Anne M

    2013-11-01

    Children in foster care have often encountered a range of adverse experiences, including neglectful and/or abusive care and multiple caregiver transitions. Prior research findings suggest that such experiences negatively affect inhibitory control and the underlying neural circuitry. In the current study, event-related functional magnetic resonance imaging was employed during a go/no go task that assesses inhibitory control to compare the behavioral performance and brain activation of foster children and nonmaltreated children. The sample included two groups of 9- to 12-year-old children: 11 maltreated foster children and 11 nonmaltreated children living with their biological parents. There were no significant group differences on behavioral performance on the task. In contrast, patterns of brain activation differed by group. The nonmaltreated children demonstrated stronger activation than did the foster children across several regions, including the right anterior cingulate cortex, the middle frontal gyrus, and the right lingual gyrus, during correct no go trials, whereas the foster children displayed stronger activation than the nonmaltreated children in the left inferior parietal lobule and the right superior occipital cortex, including the lingual gyrus and cuneus, during incorrect no go trials. These results provide preliminary evidence that the early adversity experienced by foster children impacts the neural substrates of inhibitory control.

  10. Evaluating the antioxidant and acetylcholinesterase inhibitory activity of three Centaurea species

    Directory of Open Access Journals (Sweden)

    H. Hajimehdipoor

    2014-01-01

    Full Text Available Factors such as oxidative stress and reduced acetylcholine level have been implicated in Alzheimer’s disease (AD pathology and recently there has been a trend towards natural product research to find potential sources of antioxidants and acetylcholinesterase inhibitors in the plants kingdom. Centaurea is a genus with about 500 species world wild, many of them have shown to possess biologic activity; Centaurea albonites, C. aucheri and C. pseudoscabiosa are three species which little investigation has been carried out about their biological properties. In the present study, the antioxidant and acetylcholinesterase inhibitory activity of the above mentioned species have been evaluated. The ability of the total extract and methanol fraction of the plants to scavenge free radicals has been assessed through DPPH radical scavenging assay, and the acetylcholinesterase inhibitory property has been evaluated by Ellman method. The total extract of all species exhibited moderate antioxidant activity whereas the extracts of C. pseudoscabiosa showed the strongest antioxidant property; its total extract also demonstrated the highest acetylcholinesterase inhibitory activity among the evaluated samples (19.2% inhibition. The results suggest the species as potential sources of natural antioxidants which could be focused in future studies of Alzheimer’s disease.

  11. Antioxidant, Iron Chelating and Tyrosinase Inhibitory Activities of Extracts from Talinum triangulare Leach Stem

    Directory of Open Access Journals (Sweden)

    Ana Paula Oliveira Amorim

    2013-07-01

    Full Text Available The aim of this work is to evaluate the antioxidant activity against the radical species DPPH, the reducing capacity against Fe II ions, and the inhibitory activity on the tyrosinase enzyme of the T. triangulare. Hydromethanolic crude extract provided two fractions after the liquid/liquid partition with chloroform. The Folin-Ciocalteu method determined the total phenolic content of the crude extract (CE and the hydromethanolic fraction (Fraction 1, resulting in a concentration of 0.5853 g/100 g for Fraction 1, and 0.1400 g/100 g for the CE. Taking into account the results of the DPPH, the free radical scavenging capacity was confirmed. The formation of complexes with Fe II ions was evaluated by UV/visible spectrometry; results showed that CE has complexing power similar to the positive control (Gingko biloba extract.The inhibitory capacity of samples against the tyrosinase enzyme was determined by the oxidation of L-DOPA, providing IC50 values of 13.3 μg·mL−1 (CE and 6.6 μg·mL−1 (Fraction 1. The values indicate that Fraction 1 was more active and showed a higher inhibitory power on the tyrosinase enzyme than the ascorbic acid, used as positive control. The hydromethanolic extract of T. triangulare proved to have powerful antioxidant activity and to inhibit the tyrosinase enzyme; its potential is increased after the partition with chloroform.

  12. Linking trait-based phenotypes to prefrontal cortex activation during inhibitory control.

    Science.gov (United States)

    Rodrigo, Achala H; Di Domenico, Stefano I; Graves, Bryanna; Lam, Jaeger; Ayaz, Hasan; Bagby, R Michael; Ruocco, Anthony C

    2016-01-01

    Inhibitory control is subserved in part by discrete regions of the prefrontal cortex whose functionality may be altered according to specific trait-based phenotypes. Using a unified model of normal range personality traits, we examined activation within lateral and medial aspects of the prefrontal cortex during a manual go/no-go task. Evoked hemodynamic oxygenation within the prefrontal cortex was measured in 106 adults using a 16-channel continuous-wave functional near-infrared spectroscopy system. Within lateral regions of the prefrontal cortex, greater activation was associated with higher trait levels of extraversion, agreeableness and conscientiousness, and lower neuroticism. Higher agreeableness was also related to more activation in the medial prefrontal cortex during inhibitory control. These results suggest that personality traits reflecting greater emotional stability, extraversion, agreeableness and conscientiousness may be associated with more efficient recruitment of control processes subserved by lateral regions of the prefrontal cortex. These findings highlight key links between trait-based phenotypes and neural activation patterns in the prefrontal cortex underlying inhibitory control.

  13. Antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) under different cultivation conditions.

    Science.gov (United States)

    Chen, Lei; Kang, Young-Hwa

    2014-03-12

    An adaptation of cultural management to the specific cultural system, as well as crop demand, can further result in the improvement of the quality of horticultural products. Therefore, this study focused on the antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) grown in hydroponics in comparison with those of the plant grown in soil. The antioxidant activities of Plebeian herba extract were measured as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities as well as the reducing power by decreasing nitric oxide (NO) and superoxide dismutase activity (SOD) in vitro. Interestingly, by comparison with hydroponics and traditional cultivation, Plebeian herba cultivated in nutrition-based soil improved inhibitory effect on free radicals of DPPH, ABTS, and NO and increased the contents of phenolics such as caffeic acid (1), luteolin-7-glucoside (2), homoplantaginin (3), hispidulin (4), and eupatorin. Free radical scavenging and SOD activity, as well as α-glucosidase inhibitory effect, were higher in Plebeian herba grown in nutrition-based soil than in plants grown in hydroponics and traditional condition.

  14. Effect of phlorotannins isolated from Ecklonia cava on angiotensin I-converting enzyme (ACE) inhibitory activity.

    Science.gov (United States)

    Wijesinghe, W A J P; Ko, Seok-Chun; Jeon, You-Jin

    2011-04-01

    Inhibition of angiotensin I-converting enzyme (ACE) activity is the most common mechanism underlying the lowering of blood pressure. In the present study, five organic extracts of a marine brown seaweed Ecklonia cava were prepared by using ethanol, ethyl acetate, chloroform, hexane, and diethyl ether as solvents, which were then tested for their potential ACE inhibitory activities. Ethanol extract showed the strongest ACE inhibitory activity with an IC(50) value of 0.96 mg/ml. Five kinds of phlorotannins, phloroglucinol, triphlorethol-A, eckol, dieckol, and eckstolonol, were isolated from ethanol extract of E. cava, which exhibited potential ACE inhibition. Dieckol was the most potent ACE inhibitor and was found to be a non-competitive inhibitor against ACE according to Lineweaver-Burk plots. Dieckol had an inducible effect on the production of NO in EAhy926 cells without having cytotoxic effect. The results of this study indicate that E. cava could be a potential source of phlorotannins with ACE inhibitory activity for utilization in production of functional foods.

  15. Effects of incentives, age, and behavior on brain activation during inhibitory control: A longitudinal fMRI study

    Directory of Open Access Journals (Sweden)

    David J. Paulsen

    2015-02-01

    Full Text Available We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.

  16. Effects of incentives, age, and behavior on brain activation during inhibitory control: a longitudinal fMRI study.

    Science.gov (United States)

    Paulsen, David J; Hallquist, Michael N; Geier, Charles F; Luna, Beatriz

    2015-02-01

    We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.

  17. Phaeophytins from Thyrsacanthus ramosissimus Moric. with inhibitory activity on human DNA topoisomerase II-{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Cabral, Analucia Guedes Silveira; Tenorio-Souza, Fabio Henrique; Moura, Marcelo Dantas; Mota, Sabrina Gondim Ribeiro; Silva Lins, Antonio Claudio da; Dias, Celidarque da Silva; Barbosa-Filho, Jose Maria [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Dept. de Ciencias Frmaceuticas; Giulietti, Ana Maria [Universidade Estadual de Feira de Santana, Feira de Santana, BA (Brazil). Dept. de Ciencias Biologicas; Silva, Tania Maria Sarmento da [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Dept. de Ciencias Moleculares; Santos, Creusioni Figueredo dos, E-mail: jbarbosa@ltf.ufpb.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Dept. de Biologia Molecular

    2012-07-01

    Our study reports the extraction and isolation of a new phaeophytin derivative 15{sup 1}-hydroxy-(15{sup 1}-S)-porphyrinolactone, designated anamariaine (1) herein, isolated from the chloroform fraction of aerial parts of Thyrsacanthus ramosissimus Moric. along with the known 15{sup 1}-ethoxy-(15{sup 1}-S)-porphyrinolactone (2). These compounds were identified by usual spectroscopic methods. Both compounds were subjected to in vitro (inhibitory activity) tests by means of supercoiled DNA relaxation techniques and were shown to display inhibitory activity against human DNA topoisomerase II-{alpha} at 50 {mu}M. Interconversion of these two pigments under the mild conditions of the isolation techniques should be highly unlikely but cannot be entirely ruled out. (author)

  18. Screening of Korean Medicinal Plant Extracts for α-Glucosidase Inhibitory Activities.

    Science.gov (United States)

    Sancheti, Shruti; Sancheti, Sandesh; Lee, Seung-Hun; Lee, Jae-Eun; Seo, Sung-Yum

    2011-01-01

    Glycosidases are the enzymes involved in various biochemical processes related to metabolic disorders and diseases. Therefore, much effort has been focused on searching novel pharmacotherapy for the treatment of these ailments from medicinal plants due to higher safety margins. To pursue these efforts, the present study was performed to evaluate the α-glucosidase inhibitory activities of thirty Korean medicinal plant extracts. Among the plants studied, Euonymus sachalinensis, Rhododendron schlippenbachii, Astilbe chinensis and Juglans regia showed the strongest α-glucosidase inhibitory activity with IC50 values of 10, 20, 30 and 80 µg/mL, respectively. In addition, Meliosma oldhamii and Symplocos chinensis showed moderate α-glucosidase inhibition with IC50 values of 150 and 220 µg/mL, respectively. Therefore, they might prove to be a potential natural source for the treatment of metabolic ailments such as, diabetes, and need further investigations.

  19. Jojoba seed meal proteins associated with proteolytic and protease inhibitory activities.

    Science.gov (United States)

    Shrestha, Madan K; Peri, Irena; Smirnoff, Patricia; Birk, Yehudith; Golan-Goldhirsh, Avi

    2002-09-25

    The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins.

  20. New Phragmalin-Type Limonoids from Chukrasia tabularis and Their α-Glucosidase Inhibitory Activity

    Directory of Open Access Journals (Sweden)

    Jun-Lin Peng

    2016-01-01

    Full Text Available Phytochemical investigation on the stems of C. tabularis led to the isolation of five new phragmalin-type limonoids and six known ones. The structures of the new compounds 1–5, named chukbularisins A–E, were elucidated by spectroscopic techniques (IR, HRESIMS, 1D and 2D NMR and comparisons with published data. All the compounds were evaluated for in vitro α-glucosidase inhibitory activity. Compounds 2, 3, 4, 5, and 8 exhibited inhibitory activity against α-glucosidase with IC50 values of 0.06 ± 0.008, 0.04 ± 0.002, 0.52 ± 0.039, 1.09 ± 0.040, and 0.20 ± 0.057 mM, respectively (using acarbose as positive control, IC50 0.95 ± 0.092 mM.

  1. Extraction optimization of polyphenols, antioxidant and xanthine oxidase inhibitory activities from Prunus salicina Lindl.

    Directory of Open Access Journals (Sweden)

    Yibin LI

    2016-01-01

    Full Text Available Abstract Optimization of polyphenols extraction from plum (Prunus salicina Lindl. was evaluated using response surface methodology. The Box-Behnken experimental results showed the optimal conditions involved an extraction temperature of 59 °C, a sonication time of 47 min, and an ethanol concentration of 61% respectively. The maximum extraction yield of total polyphenols was 44.74 mg gallic acid equivalents per gram of dried plum at optimal conditions. Polyphenol extracts exhibited stronger antioxidant activities than Vc by evaluating of 1,1-diphenyl-2-picrylhydrazyl (DPPH and hydroxyl radical scavenging activity. Furthermore, polyphenol extracts (IC50 = 179 g/mL showed obvious inhibitory effects on xanthine oxidase. These findings suggest that polyphenol extracts from P. salicina can be potentially used as natural antioxidant and xanthine oxidase inhibitory agents.

  2. Synthesis, characterization and carbonic anhydrase inhibitory activity of novel benzothiazole derivatives.

    Science.gov (United States)

    Küçükbay, F Zehra; Buğday, Nesrin; Küçükbay, Hasan; Tanc, Muhammet; Supuran, Claudiu T

    2016-12-01

    N-protected amino acids were reacted with substituted benzothiazoles to give the corresponding N-protected amino acid-benzothiazole conjugates (60-89%). Their structures were confirmed by proton nuclear magnetic resonance ((1)H NMR), carbon-13 nuclear magnetic resonance ((13)C NMR), IR and elemental analysis. Their carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activities were determined against two cytosolic human isoforms (hCA I and hCA II), one membrane-associated (hCA IV) and one transmembrane (hCA XII) enzyme by a stopped-flow CO2 hydrase assay method. The new compounds showed rather weak, micromolar inhibitory activity against most of these enzymes.

  3. Cholinesterase inhibitory activity and chemical constituents of Stenochlaena palustris fronds at two different stages of maturity

    Directory of Open Access Journals (Sweden)

    Nelson Jeng-Yeou Chear

    2016-04-01

    Full Text Available Stenochlaena palustris fronds are popular as a vegetable in Southeast Asia. The objectives of this study were to evaluate the anticholinesterase properties and phytochemical profiles of the young and mature fronds of this plant. Both types of fronds were found to have selective inhibitory effect against butyrylcholinesterase compared with acetylcholinesterase. However, different sets of compounds were responsible for their activity. In young fronds, an antibutyrylcholinesterase effect was observed in the hexane extract, which was comprised of a variety of aliphatic hydrocarbons, fatty acids, and phytosterols. In the mature fronds, inhibitory activity was observed in the methanol extract, which contained a series of kaempferol glycosides. Our results provided novel information concerning the ability of S. palustris to inhibit cholinesterase and its phytochemical profile. Further research to investigate the potential use of this plant against Alzheimer's disease is warranted, however, young and mature fronds should be distinguished due to their phytochemical differences.

  4. Chemical Constituents of Jacaranda oxyphylla and their Acetylcholinesterase Inhibitory and Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Vinicius Viana Pereira

    2016-05-01

    Full Text Available This study evaluated chemical composition of Jacaranda oxyphylla, acetylcholinesterase inhibitory and antimicrobial activities of the isolated compounds. Phytochemical investigation of leaves extract yielded three classes of substances: fatty compounds, sterols and triterpenes. Butyl hexadecanoate (1, fatty alcohol (2, 2-(4-hydroxyphenylethyl triacontanoate (3, β -sitosterol (4, sitosterol-3-O- β- D -glucoside (5, 6'-palmitoyl-sitosterol-3-O- β- D -glucoside (6, oleanolic acid (7, ursolic acid (8 and corosolic acid (9 were obtained from n-hexane, CHCl 3 and EtOH extracts of J. oxyphylla. It was found a pronounced acetylcholinesterase inhibitory activity for the fatty compounds 1-3 and sterols 5 and 6, with values between 60 to 77%. Substances 7-9 presented a high antibacterial action against Bacillus cereus and Salmonella typhimurium, with values of growth inhibition in the range of 84 to 90%.

  5. Bergamotane Sesquiterpenes with Alpha-Glucosidase Inhibitory Activity from the Plant Pathogenic Fungus Penicillium expansum.

    Science.gov (United States)

    Ying, You-Min; Fang, Cheng-An; Yao, Feng-Qi; Yu, Yuan; Shen, Ying; Hou, Zhuo-Ni; Wang, Zhen; Zhang, Wei; Shan, Wei-Guang; Zhan, Zha-Jun

    2017-01-01

    Two new bergamotane sesquiterpene lactones, named expansolides C and D (1 and 2), together with two known compounds expansolides A and B (3 and 4), were isolated from the plant pathogenic fungus Penicillium expansum ACCC37275. The structures of the new compounds were established by detailed analyses of the spectroscopic data, especially 1D-, 2D-NMR, and HR-ESI-MS. In an in vitro bioassay, the epimeric mixture of expansolides C and D (1 and 2) (in a ratio of 2:1 at the temprature of the bioassay) exhibited more potent α-glucosidase inhibitory activity (IC50 =0.50 ± 0.02 mm) as compared with the positive control acarbose (IC50 = 1.90 ± 0.05 mm). To the best of our knowledge, it was the first report on the α-glucosidase inhibitory activity of bergamotane sesquiterpenes.

  6. Predicting the DPP-IV inhibitory activity pIC₅₀ based on their physicochemical properties.

    Science.gov (United States)

    Gu, Tianhong; Yang, Xiaoyan; Li, Minjie; Wu, Milin; Su, Qiang; Lu, Wencong; Zhang, Yuhui

    2013-01-01

    The second development program developed in this work was introduced to obtain physicochemical properties of DPP-IV inhibitors. Based on the computation of molecular descriptors, a two-stage feature selection method called mRMR-BFS (minimum redundancy maximum relevance-backward feature selection) was adopted. Then, the support vector regression (SVR) was used in the establishment of the model to map DPP-IV inhibitors to their corresponding inhibitory activity possible. The squared correlation coefficient for the training set of LOOCV and the test set are 0.815 and 0.884, respectively. An online server for predicting inhibitory activity pIC50 of the DPP-IV inhibitors as described in this paper has been given in the introduction.

  7. ACE-I Inhibitory Activity from Phaseolus lunatus and Phaseolus vulgaris Peptide Fractions Obtained by Ultrafiltration.

    Science.gov (United States)

    Betancur-Ancona, David; Dávila-Ortiz, Gloria; Chel-Guerrero, Luis Antonio; Torruco-Uco, Juan Gabriel

    2015-11-01

    The involvement of angiotensin-I-converting enzyme (ACE-I) as one of the mechanisms controlling blood pressure is being studied to find alternative means of control of hypertension on human beings. On the market there are synthetic drugs that can control it, but these can cause undesirable health side effects. In this work was assessed the fractionation by ultrafiltration of the Lima bean (Phaseolus lunatus) and Jamapa bean (Phaseolus vulgaris), protein hydrolysates obtained with Alcalase(®) and Flavourzyme(®) on ACE-I inhibitory activity. Four membranes of different molecular cutoffs (10, 5, 3, and 1 kDa) were used. Fractions that had a higher inhibitory activity in both legumes were denominated as E (obtaining and utilizing these peptide fractions in the development and innovation of a functional product that helps with treatment and/or prevention of hypertension.

  8. Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity.

    Science.gov (United States)

    Nongonierma, Alice B; FitzGerald, Richard J

    2016-05-01

    Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2-5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p<0.05, R(2) of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N2 position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC50) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC50=43.8±8.8μM) and IPM (IC50=69.5±8.7μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose.

  9. A lipase with broad temperature range from an alkaliphilic gamma-proteobacterium isolated in Greenland

    DEFF Research Database (Denmark)

    Schmidt, Mariane; Larsen, Dorte Møller; Stougaard, Peter

    2010-01-01

    A gamma-proteobacterium related to the genera Alteromonadales and Pseudomonadales , isolated from a cold and alkaline environment in Greenland, has been shown to produce a lipase active between 5 ° C and 80 ° C, with optimal activity at 55 ° C and pH 8. PCR-based screening of genomic DNA from...... the isolated bacterium, followed by genome walking, resulted in two complete open reading frames, which were predicted to encode a lipase and its helper protein, a lipase foldase. The amino acid sequence derived for the lipase showed resemblance to lipases from Pseudomonas , Rhodoferax, Aeromonas and Vibrio...... . The two genes were cloned into different expression systems in E. coli with or without a putative secretion sequence, but despite the fact that both recombinant lipase and lipase foldase were observed on SDS–PAGE, no recombinant lipase activity was detected. Attempts to refold the recombinant lipase...

  10. Inhibitory activity against urease of quercetin glycosides isolated from Allium cepa and Psidium guajava.

    Science.gov (United States)

    Shabana, Samah; Kawai, Azusa; Kai, Kenji; Akiyama, Kohki; Hayashi, Hideo

    2010-01-01

    Methanolic extracts of edible plants and seaweeds were tested for their inhibitory activity against Jack bean urease. Quercetin-4'-O-beta-D-glucopyranoside was isolated from Allium cepa as a urease inhibitor with an IC(50) value of 190 microM-. Quercetin and two quercetin glycosides, avicularin and guaijaverin, were isolated from Psidium guajava as urease inhibitors with respective IC(50) values of 80 microM-, 140 microM-, and 120 microM-.

  11. Screening of Korean Medicinal Plant Extracts for α-Glucosidase Inhibitory Activities

    OpenAIRE

    Sancheti,Shruti; Sancheti,Sandesh; LEE, Seung-Hun; Lee, Jae-Eun; Seo, Sung-Yum

    2011-01-01

    Glycosidases are the enzymes involved in various biochemical processes related to metabolic disorders and diseases. Therefore, much effort has been focused on searching novel pharmacotherapy for the treatment of these ailments from medicinal plants due to higher safety margins. To pursue these efforts, the present study was performed to evaluate the α-glucosidase inhibitory activities of thirty Korean medicinal plant extracts. Among the plants studied, Euonymus sachalinensis, Rhododendron sch...

  12. Effects of nanosuspension and inclusion complex techniques on the in vitro protease inhibitory activity of naproxen

    OpenAIRE

    Dharmalingam, Senthil Rajan; Chidambaram, Kumarappan; Ramamurthy, Srinivasan; Nadaraju,Shamala

    2014-01-01

    This study investigated the effects of nanosuspension and inclusion complex techniques on in vitro trypsin inhibitory activity of naproxen—a member of the propionic acid derivatives, which are a group of antipyretic, analgesic, and non-steroidal anti-inflammatory drugs. Nanosuspension and inclusion complex techniques were used to increase the solubility and anti-inflammatory efficacy of naproxen. The evaporative precipitation into aqueous solution (EPAS) technique and the kneading metho...

  13. Bioactive Compounds, Antioxidant, Xanthine Oxidase Inhibitory, Tyrosinase Inhibitory and Anti-Inflammatory Activities of Selected Agro-Industrial By-products

    Directory of Open Access Journals (Sweden)

    Ehsan Karimi

    2011-11-01

    Full Text Available Evaluation of abundantly available agro-industrial by-products for their bioactive compounds and biological activities is beneficial in particular for the food and pharmaceutical industries. In this study, rapeseed meal, cottonseed meal and soybean meal were investigated for the presence of bioactive compounds and antioxidant, anti-inflammatory, xanthine oxidase and tyrosinase inhibitory activities. Methanolic extracts of rapeseed meal showed significantly (P < 0.01 higher phenolics and flavonoids contents; and significantly (P < 0.01 higher DPPH and nitric oxide free radical scavenging activities when compared to that of cottonseed meal and soybean meal extracts. Ferric thiocyanate and thiobarbituric acid tests results showed rapeseed meal with the highest antioxidant activity (P < 0.01 followed by BHT, cotton seed meal and soybean meal. Rapeseed meal extract in xanthine oxidase and tyrosinase inhibitory assays showed the lowest  IC50 values  followed by cottonseed and soybean meals. Anti-inflammatory assay using IFN-γ/LPS stimulated RAW 264.7 cells indicated rapeseed meal is a potent source of anti-inflammatory agent. Correlation analysis showed that phenolics and flavonoids were highly correlated to both antioxidant and anti-inflammatory activities. Rapeseed meal was found to be promising as a natural source of bioactive compounds with high antioxidant, anti-inflammatory, xanthine oxidase and tyrosinase inhibitory activities in contrast to cotton and soybean meals.

  14. Sex differences in hormone-sensitive lipase expression, activity, and phosphorylation in skeletal muscle at rest and during exercise

    DEFF Research Database (Denmark)

    Roepstorff, Carsten; Donsmark, Morten; Thiele, Maja

    2006-01-01

    Women have been shown to use more intramuscular triacylglycerol (IMTG) during exercise than men. To investigate whether this could be due to sex-specific regulation of hormone-sensitive lipase (HSL) and to use sex comparison as a model to gain further insight into HSL regulation, nine women and e...

  15. Altering the activation mechanism in Thermomyces lanuginosus lipase

    DEFF Research Database (Denmark)

    Skjold-Jørgensen, Jakob; Vind, Jesper; Svendsen, Allan

    2014-01-01

    activation at the lipid interface. Relative to their activity toward pNP-ester substrates in calcium-rich buffer, all lid variants retained between 15 and 100% activity in buffer containing 5 mM EDTA whereas TlL activity was reduced to less than 2%, demonstrating the lid's central role in governing calcium...... dependency. For FAEA-like lid variants, accessible hydrophobic surface area measurements showed an approximate 10-fold increase in the level of binding of extrinsic fluorophores to the protein surface relative to that of TlL accompanied by a blue shift in emission indicative of an open lid in aqueous...

  16. Inhibitory Effects of Garcinia cambogia Extract on CYP2B6 Enzyme Activity.

    Science.gov (United States)

    Yu, Jun Sang; Choi, Min Sun; Park, Jong Suk; Rehman, Shaheed Ur; Nakamura, Katsunori; Yoo, Hye Hyun

    2017-03-13

    This study assessed the inhibitory effects of Garcinia cambogia extract on the cytochrome P450 enzymes in vitro. G. cambogia extract was incubated with cytochrome P450 isozyme-specific substrates in human liver microsomes and recombinant CYP2B6 isozyme, and the formation of the marker metabolites was measured to investigate the inhibitory potential on cytochrome P450 enzyme activities. The results showed that G. cambogia extract has significant inhibitory effects on CYP2B6 activity in a concentration-dependent manner. Furthermore, the inhibition was potentiated following preincubation with NADPH, indicating that G. cambogia extract is a time-dependent inhibitor of CYP2B6. Meanwhile, hydroxycitric acid, the major bioactive ingredient of G. cambogia extract, did not exhibit significant inhibition effects on cytochrome P450 enzyme activities. G. cambogia extract could modulate the pharmacokinetics of CYP2B6 substrate drugs and lead to interactions with those drugs. Therefore, caution may be required with respect to concomitant intake of dietary supplements containing G. cambogia extract with CYP2B6 substrates.

  17. Molecular Descriptors Family on Vertex Cutting: Relationships between Acelazolamide Structures and their Inhibitory Activity

    Directory of Open Access Journals (Sweden)

    Sorana D. BOLBOACĂ

    2009-12-01

    Full Text Available Aim: To investigate the relationship between the structural information of acetazolamides and their inhibitory activity on carbonic anhydrase II. Material and Method: A sample of previously reported acetazolamides was studied. A pool of descriptors was calculated based on matrix representation and vertex cut in order to be included in the multiple linear regression analysis. The best performing model in terms of goodness-of-fit was analysed in order to assess its validity and reliability. The model was compared with previously reported models using a series of information and prediction criteria besides the Steiger’s Z test. Results: A model with a 99.77% determination coefficient proved to be the best performing model. The obtained model proved to have a less than 5% average of the absolute difference between the observed and the estimated inhibitory activity. The information and prediction criteria showed that the obtained model was better than the previously reported models. This conclusion is also sustained by the results of Steiger’s Z test (7.78; p = 3.66·10-15. Conclusion: The inhibitory activity on carbonic anhydrase II of acetazolamides proved to be of geometric and topologic nature and depended on the compounds’ melting point, relative atomic mass and atomic electronegativity.

  18. Hypotensive and Angiotensin-Converting Enzyme Inhibitory Activities of Eisenia fetida Extract in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Shumei Mao

    2015-01-01

    Full Text Available Objectives. This study aimed to investigate the antihypertensive effects of an Eisenia fetida extract (EFE and its possible mechanisms in spontaneously hypertensive rats (SHR rats. Methods. Sixteen-week-old SHR rats and Wistar-Kyoto rats (WKY rats were used in this study. Rats were, respectively, given EFE (EFE group, captopril (captopril group, or phosphate-buffered saline (PBS (normal control group and SHR group for 4 weeks. ACE inhibitory activity of EFE in vitro was determined. The systolic blood pressure (SBP and diastolic blood pressure (DBP were measured using a Rat Tail-Cuff Blood Pressure System. Levels of angiotensin II (Ang II, aldosterone (Ald, and 6-keto-prostaglandin F1 alpha (6-keto-PGF1α in plasma were determined by radioimmunoassay, and serum nitric oxide (NO concentration was measured by Griess reagent systems. Results. EFE had marked ACE inhibitory activity in vitro (IC50 = 2.5 mg/mL. After the 4-week drug management, SHR rats in EFE group and in captopril group had lower SBP and DBP, lower levels of Ang II and Ald, and higher levels of 6-keto-PGF1α and NO than the SHR rats in SHR group. Conclusion. These results indicate that EFE has hypotensive effects in SHR rats and its effects might be associated with its ACE inhibitory activity.

  19. Efficient production of active recombinant Candida rugosa LIP3 lipase in Pichia pastoris and biochemical characterization of the purified enzyme.

    Science.gov (United States)

    Chang, Shu-Wei; Lee, Guan-Chiun; Shaw, Jei-Fu

    2006-08-09

    Candida rugosa lipase (CRL), an important industrial enzyme, possesses several different isoforms encoded by the high-identity lip gene family (lip1 to lip7). In this study, an additional N-terminal peptide in front of the lip3 gene was removed by PCR, and the 18 nonuniversal serine codons (CTG) of the lip3 gene were converted into universal serine codons (TCT) by means of an overlap extension PCR-based multiple-site-directed mutagenesis to express an active recombinant LIP3 in the yeast Pichia pastoris. The regional synthetic DNA fragment (339 bp) is first recombined by primer assembly with 20 overlapping nucleotides, followed by specific overlap extension PCR with outside primers containing restriction enzyme sites for directional cloning into the pGAPZalphaC vector. The results show that the production yield (0.687 unit/mL) of N-fused lip3 (nflip3) has an overall improvement of 69-fold relative to that (0.01 unit/mL) of lip3 and of 52-fold (0.47 unit/mL) of codon-optimized lip3 (colip3) relative to that (0.01 unit/mL) of non-codon-optimized lip3 (lip3), with the cultivation time set at 5 days. This finding demonstrates that the reservation of the N terminus and the regional codon optimization of the lip3 gene fragment at the 5' end can greatly increase the expression level of recombinant LIP3 in the P. pastoris system. The purified recombinant LIP3 shows distinct biochemical properties compared with other isoforms.

  20. Advances in lipase-catalyzed esterification reactions.

    Science.gov (United States)

    Stergiou, Panagiota-Yiolanda; Foukis, Athanasios; Filippou, Michalis; Koukouritaki, Maria; Parapouli, Maria; Theodorou, Leonidas G; Hatziloukas, Efstathios; Afendra, Amalia; Pandey, Ashok; Papamichael, Emmanuel M

    2013-12-01

    Lipase-catalyzed esterification reactions are among the most significant chemical and biochemical processes of industrial relevance. Lipases catalyze hydrolysis as well as esterification reactions. Enzyme-catalyzed esterification has acquired increasing attention in many applications, due to the significance of the derived products. More specifically, the lipase-catalyzed esterification reactions attracted research interest during the past decade, due to an increased use of organic esters in biotechnology and the chemical industry. Lipases, as hydrolyzing agents are active in environments, which contain a minimum of two distinct phases, where all reactants are partitioned between these phases, although their distribution is not fixed and changes as the reaction proceeds. The kinetics of the lipase-catalyzed reactions is governed by a number of factors. This article presents a thorough and descriptive evaluation of the applied trends and perspectives concerning the enzymatic esterification, mainly for biofuel production; an emphasis is given on essential factors, which affect the lipase-catalyzed esterification reaction. Moreover, the art of using bacterial and/or fungal strains for whole cell biocatalysis purposes, as well as carrying out catalysis by various forms of purified lipases from bacterial and fungal sources is also reviewed.

  1. FRAKSINASI ENZIM LIPASE DARI ENDOSPERM KELAPA DENGAN METODE SALTING OUT (Lipase fractionation of Coconut Endosperm by Salting out Method

    Directory of Open Access Journals (Sweden)

    Moh. Su'i

    2014-02-01

    Full Text Available This research learns about fractionation of lipases activity from coconut endosperm by using ammonium sulphate of 0–15%; 15-30 %, 30–45 %, 45–60 %, 60–75 % and 75–90 %. The results showed that the fractions of 0–15% ; 30–45 %, 45–60 % and 60–75 % have lipase activity. Meanwhile, the highest activity was fractions of 60-75%. fractions of 15-30% and 75-90%  have no lipase enzym activity. Molecule weigh of lipase enzyme was 72 kDa. Keywords: Lipases, endosperm, coconut, fractionation, ammonium sulphate   ABSTRAK Penelitian ini mempelajari fraksinasi enzim lipase dari endosperm kelapa menggunakan ammonium sulfat. fraksinasi dilakukan dengan variasi konsentrasi ammonium sulfat 0–15% ; 15-30%; 30–45 %, 45–60 %, 60–75 % dan 75–90 %. Hasil penelitian menunjukkan bahwa enzim lipase terdapat pada fraksi 0–15% ; 30–45 %, 45–60 % dan fraksi 60–75 % dengan aktivitas enzim tertinggi pada fraksi 60-75%. Sedangkan fraksi 15-30% dan 75-90% tidak ada enzim lipase. Berat molekul enzim lipase pada semua fraksi 72 kDa. Kata kunci: Lipase, endosperm, fraksinasi, ammonium sulfat

  2. 8-hydroxydihydrochelerythrine and 8-hydroxydihydrosanguinarine with a potent acetylcholinesterase inhibitory activity from Chelidonium majus L.

    Science.gov (United States)

    Cho, Kyung-Mi; Yoo, Ick-Dong; Kim, Won-Gon

    2006-11-01

    Ethanol extract of the aerial portion of Chelidonium majus L. inhibited acetylcholinesterase (AChE) activity without a significant inhibition of butyrylcholinesterase (BuChE). Using mass spectrometry and NMR studies, three active constituents were isolated and identified: 8-hydroxydihydrochelerythrine (1), 8-hydroxydihydrosanguinarine (2), and berberine (3). Compounds 1-3 showed potent inhibitory activity against AChE, with IC50 (microM) values of 0.61-1.85. Compound 1 exhibited competitive and selective inhibition for AChE.

  3. Synthesis of rotenoid derivatives with cytotoxic and topoisomerase II inhibitory activities.

    Science.gov (United States)

    Sangthong, Supranee; Krusong, Kuakarun; Ngamrojanavanich, Nattaya; Vilaivan, Tirayut; Puthong, Songchan; Chandchawan, Supajittra; Muangsin, Nongnuj

    2011-08-15

    6-Deoxyclitoriacetal (1) and a series of 11 further derivatives of it (2-12) were synthesized and evaluated for their cytotoxic and topoisomerase IIα inhibitory activities. Compounds bearing epoxide (2), morpholine (6) and benzylamine (10) moieties showed promising in vitro cytotoxic activities against four cancer cell lines, with IC(50) values ranging from 0.38 to 0.73 μM. These three compounds also strongly inhibited topoisomerase II activity at 68.3-93.5% and showed a moderately high DNA intercalating property.

  4. Characterization of fasted human gastric fluid for relevant rheological parameters and gastric lipase activities

    DEFF Research Database (Denmark)

    Pedersen, Pernille Barbre; Vilmann, Peter; Bar-Shalom, Daniel

    2013-01-01

    be considered important during development of gastric simulated media. Further, the activity of the HGL is active even under fasted gastric conditions and might contribute to the digestion and emulsification of lipid-based drug delivery systems in the entire gastrointestinal tract. HGL should therefore...... be considered in gastric evaluation of lipid-based drug delivery systems....

  5. Lysosomal Acid Lipase Activity Is Reduced Both in Cryptogenic Cirrhosis and in Cirrhosis of Known Etiology.

    Directory of Open Access Journals (Sweden)

    Umberto Vespasiani-Gentilucci

    Full Text Available Liver cirrhosis is characterized by a severe acquired reduction of LAL-activity, the precise causes and consequences of which need to be further addressed. DBS-determined lysosomal enzyme activities seem to be affected by white blood cell and platelet counts, and the specificity of these tests can be reduced when applied to determined populations, such as cirrhotics.

  6. Inhibitory activity of garlic (Allium sativum extract on multidrug-resistant Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Fani M

    2007-01-01

    Full Text Available Garlic ( Allium sativum extract has been known to have inhibitory activity on various pathogenic bacteria, viruses and fungi. The objective of present investigation was to study in vitro inhibitory activity of garlic extract on multidrug-resistant (MDR strains of Streptococcus mutans isolated from human carious teeth. Filter sterilized aqueous extract of garlic was prepared and used in the present study. For isolation of S. mutans , extracted human carious teeth were cultured in Todd-Hewit broth and Mitis-Salivarius-Bacitracin agar. S. mutans was characterized by colony morphology, biochemical tests and other conventional bacteriological procedures. Disk sensitivity tests and broth dilution methods were used to determine antibiotic sensitivity profile and inhibitory activity of garlic extract on S. mutans isolated from carious teeth. Of 105 carious teeth tested, 92 (87.6% isolates of S. mutans were recovered, among which 28 (30.4% were MDR since they were resistant to four or more antibiotics. The highest rate of resistance was observed for tetracycline (30.4% and least resistance (0% to teichoplanin and vancomycin while 22.8% and 23.9% of the isolates were resistant to penicillin and amoxicillin, respectively. Chlorhexidine minimum inhibitory concentration (MIC for MDR and non-MDR S. mutans varied from 2 to 16 µg ml−1 and from 0.25 to 1 µg ml−1 , respectively ( P < 0.05. All isolates, MDR and non-MDR of S. mutans were sensitive to garlic extract with the MIC ranging from 4 to 32 mg ml−1 . Considering in vitro data obtained in the present study, mouthwashes or toothpaste containing optimum concentration of garlic extract could be used for prevention of dental caries.

  7. Growth inhibitory activity of extracts and compounds from Cimicifuga species on human breast cancer cells.

    Science.gov (United States)

    Einbond, Linda Saxe; Wen-Cai, Ye; He, Kan; Wu, Hsan-au; Cruz, Erica; Roller, Marc; Kronenberg, Fredi

    2008-06-01

    The purpose of this report is to explore the growth inhibitory effect of extracts and compounds from black cohosh and related Cimicifuga species on human breast cancer cells and to determine the nature of the active components. Black cohosh fractions enriched for triterpene glycosides and purified components from black cohosh and related Asian species were tested for growth inhibition of the ER(-) Her2 overexpressing human breast cancer cell line MDA-MB-453. Growth inhibitory activity was assayed using the Coulter Counter, MTT and colony formation assays. Results suggested that the growth inhibitory activity of black cohosh extracts appears to be related to their triterpene glycoside composition. The most potent Cimicifuga component tested was 25-acetyl-7,8-didehydrocimigenol 3-O-beta-d-xylopyranoside, which has an acetyl group at position C-25. It had an IC(50) of 3.2microg/ml (5microM) compared to 7.2microg/ml (12.1microM) for the parent compound 7,8-didehydrocimigenol 3-O-beta-d-xylopyranoside. Thus, the acetyl group at position C-25 enhances growth inhibitory activity. The purified triterpene glycoside actein (beta-d-xylopyranoside), with an IC(50) equal to 5.7microg/ml (8.4microM), exhibited activity comparable to cimigenol 3-O-beta-d-xyloside. MCF7 (ER(+)Her2 low) cells transfected for Her2 are more sensitive than the parental MCF7 cells to the growth inhibitory effects of actein from black cohosh, indicating that Her2 plays a role in the action of actein. The effect of actein on Her2 overexpressing MDA-MB-453 and MCF7 (ER(+)Her2 low) human breast cancer cells was examined by fluorescent microscopy. Treatment with actein altered the distribution of actin filaments and induced apoptosis in these cells. These findings, coupled with our previous evidence that treatment with the triterpene glycoside actein induced a stress response and apoptosis in human breast cancer cells, suggest that compounds from Cimicifuga species may be useful in the prevention and

  8. Antioxidant, ACE-Inhibitory and antibacterial activities of Kluyveromyces marxianus protein hydrolysates and their peptide fractions

    Directory of Open Access Journals (Sweden)

    Mahta Mirzaeia

    2016-07-01

    Full Text Available Background: There has been evidence that proteins are potentially excellent source of antioxidants, antihypertensive and antimicrobial peptides, and that enzymatic hydrolysis is an effective method to release these peptides from protein molecules. The functional properties of protein hydrolysates depends on the protein substrate, the specificity of the enzymes, the conditions used during proteolysis, degree of hydrolysis, and the nature of peptides released including molecular weight, amino acid composition, and hydrophobicity. Context and purpose of this study: The biomass of Kluyveromyces marxianus was considered as a source of ACE inhibitory, antioxidant and antimicrobial peptides. Results: Autolysis and enzymatic hydrolysis were completed respectively, after 96 h and 5 h. Overall, trypsin (18.52% DH and chymotrypsin (21.59% DH treatments were successful in releasing antioxidant and ACE inhibitory peptides. Autolysate sample (39.51% DH demonstrated poor antioxidant and ACE inhibitory activity compared to trypsin and chymotrypsin hydrolysates. The chymotrypsin 3-5 kDa (301.6±22.81 μM TE/mg protein and trypsin < 3 kDa (280.16±39.16 μM TE/mg protein permeate peptide fractions showed the highest DPPH radical scavenging activity. The trypsin <3 kDa permeate peptide fraction showed the highest ABTS radical scavenging (1691.1±48.68 μM TE/mg protein and ACE inhibitory (IC50=0.03±0.001 mg/mL activities. The fraction (MW=5-10 kD obtained after autolysis treatment showed antibacterial activity against St. aureus and Lis. monocytogenes in well diffusion screening. The minimum inhibitory concentration (MIC value was 13.3 mg/mLagainst St. aureus and Lis. monocytogenes calculated by turbidimetric assay and it showed bactericidal activity against St. aureus at 21.3 mg/mL protein concentration. Conclusions: Altogether, the results of this study reveal that K. marxianus proteins contain specific peptides in their sequences which can be released by

  9. Phagocytic receptors activate and immune inhibitory receptor SIRPalpha inhibits phagocytosis through paxillin and cofilin

    Directory of Open Access Journals (Sweden)

    Miri eGitik

    2014-04-01

    Full Text Available The innate-immune function of phagocytosis of apoptotic cells, tissue-debris, pathogens and cancer cells is essential for homeostasis, tissue repair, fighting infection and combating malignancy. Phagocytosis is carried out in the CNS by resident microglia and in both CNS and PNS by recruited macrophages. While phagocytosis proceeds, bystander healthy cells protect themselves by sending a do not eat me message to phagocytes as CD47 on their surface ligates immune inhibitory receptor SIRPα on the surface of phagocytes and SIRPα then produces the signaling which inhibits phagocytosis. This helpful mechanism becomes harmful when tissue-debris and unhealthy cells inhibit their own phagocytosis by employing the same mechanism. However, the inhibitory signaling that SIRPα produces has not been fully revealed. We focus here on how SIRPα inhibits the phagocytosis of the tissue-debris degenerated-myelin which hinders repair in axonal injury and neurodegenerative diseases. We tested whether SIRPα inhibits phagocytosis by regulating cytoskeleton function through paxillin and cofilin since (a the cytoskeleton generates the mechanical forces that drive phagocytosis and (b both paxillin and cofilin control cytoskeleton function. Paxillin and cofilin were transiently activated in microglia as phagocytosis was activated. In contrast, paxillin and cofilin were continuously activated and phagocytosis augmented in microglia in which SIRPα expression was knocked-down by SIRPα-shRNA. Further, levels of phagocytosis, paxillin activation and cofilin activation positively correlated with one another. Taken together, these observations suggest a novel mechanism whereby paxillin and cofilin are targeted to control phagocytosis by both the activating signaling that phagocytic receptors produce by promoting the activation of paxillin and cofilin and the inhibiting signaling that immune inhibitory SIRPα produces by promoting the inactivation of paxillin and cofilin.

  10. Phagocytic receptors activate and immune inhibitory receptor SIRPα inhibits phagocytosis through paxillin and cofilin.

    Science.gov (United States)

    Gitik, Miri; Kleinhaus, Rachel; Hadas, Smadar; Reichert, Fanny; Rotshenker, Shlomo

    2014-01-01

    The innate immune function of phagocytosis of apoptotic cells, tissue debris, pathogens, and cancer cells is essential for homeostasis, tissue repair, fighting infection, and combating malignancy. Phagocytosis is carried out in the central nervous system (CNS) by resident microglia and in both CNS and peripheral nervous system by recruited macrophages. While phagocytosis proceeds, bystander healthy cells protect themselves by sending a "do not eat me" message to phagocytes as CD47 on their surface ligates immune inhibitory receptor SIRPα on the surface of phagocytes and SIRPα then produces the signaling which inhibits phagocytosis. This helpful mechanism becomes harmful when tissue debris and unhealthy cells inhibit their own phagocytosis by employing the same mechanism. However, the inhibitory signaling that SIRPα produces has not been fully revealed. We focus here on how SIRPα inhibits the phagocytosis of the tissue debris "degenerated myelin" which hinders repair in axonal injury and neurodegenerative diseases. We tested whether SIRPα inhibits phagocytosis by regulating cytoskeleton function through paxillin and cofilin since (a) the cytoskeleton generates the mechanical forces that drive phagocytosis and (b) both paxillin and cofilin control cytoskeleton function. Paxillin and cofilin were transiently activated in microglia as phagocytosis was activated. In contrast, paxillin and cofilin were continuously activated and phagocytosis augmented in microglia in which SIRPα expression was knocked-down by SIRPα-shRNA. Further, levels of phagocytosis, paxillin activation, and cofilin activation positively correlated with one another. Taken together, these observations suggest a novel mechanism whereby paxillin and cofilin are targeted to control phagocytosis by both the activating signaling that phagocytic receptors produce by promoting the activation of paxillin and cofilin and the inhibiting signaling that immune inhibitory SIRPα produces by promoting the

  11. Absolute Configurations and NO Inhibitory Activities of Terpenoids from Curcuma longa.

    Science.gov (United States)

    Xu, Jing; Ji, Feifei; Kang, Jing; Wang, Hao; Li, Shen; Jin, Da-Qing; Zhang, Qiang; Sun, Hongwei; Guo, Yuanqiang

    2015-06-24

    Curcuma longa L., belonging to the Zingiberaceae family, is a perennial herb and has been used as a spice and a pigment in the food industry. In the ongoing search for inhibitory reagents of NO production and survey of the chemical composition of natural vegetable foods, the chemical constituents of C. longa used as spice were investigated. This investigation resulted in the isolation of 2 new terpenoids and 14 known analogues. Their structures were established on the basis of the extensive analyses of 1D and 2D NMR spectroscopic data, and the absolute configurations of 1-4 were elucidated by comparison of the calculated and experimental ECD spectra. Among them, compound 1 is a rare norditerpene with an ent-labdane skeleton, and 2 is a skeletally novel sesquiterpene having an eight-membered ring. All of the compounds were found to possess NO inhibitory activities in murine microglial BV-2 cells. The discovery of two new compounds in this chemical investigation further disclosed the chemical composition of C. longa used a food spice, and the bioassay implied that the natural food spice C. longa, containing terpenoids with NO inhibitory activities, may be potentially promotive to human health.

  12. Local field potentials primarily reflect inhibitory neuron activity in human and monkey cortex

    Science.gov (United States)

    Teleńczuk, Bartosz; Dehghani, Nima; Le Van Quyen, Michel; Cash, Sydney S.; Halgren, Eric; Hatsopoulos, Nicholas G.; Destexhe, Alain

    2017-01-01

    The local field potential (LFP) is generated by large populations of neurons, but unitary contribution of spiking neurons to LFP is not well characterised. We investigated this contribution in multi-electrode array recordings from human and monkey neocortex by examining the spike-triggered LFP average (st-LFP). The resulting st-LFPs were dominated by broad spatio-temporal components due to ongoing activity, synaptic inputs and recurrent connectivity. To reduce the spatial reach of the st-LFP and observe the local field related to a single spike we applied a spatial filter, whose weights were adapted to the covariance of ongoing LFP. The filtered st-LFPs were limited to the perimeter of 800 μm around the neuron, and propagated at axonal speed, which is consistent with their unitary nature. In addition, we discriminated between putative inhibitory and excitatory neurons and found that the inhibitory st-LFP peaked at shorter latencies, consistently with previous findings in hippocampal slices. Thus, in human and monkey neocortex, the LFP reflects primarily inhibitory neuron activity. PMID:28074856

  13. Evaluation of Selected Culinary-Medicinal Mushrooms for Antioxidant and ACE Inhibitory Activities

    Directory of Open Access Journals (Sweden)

    Noorlidah Abdullah

    2012-01-01

    Full Text Available Considering the importance of diet in prevention of oxidative stress-related diseases including hypertension, this study was undertaken to evaluate the in vitro antioxidant and ACE inhibitory activities of selected culinary-medicinal mushrooms extracted by boiling in water for 30 min. Antioxidant capacity was measured using the following assays: DPPH free radical scavenging activity, β-carotene bleaching, inhibition of lipid peroxidation, reducing power ability, and cupric ion reducing antioxidant capacity (CUPRAC. Antioxidant potential of each mushroom species was calculated based on the average percentages relative to quercetin and summarized as Antioxidant Index (AI. Ganoderma lucidum (30.1%, Schizophyllum commune (27.6%, and Hericium erinaceus (17.7% showed relatively high AI. Total phenolics in these mushrooms varied between 6.19 to 63.51 mg GAE/g extract. In the ACE inhibitory assay, G. lucidum was shown to be the most potent species (IC50 = 50 μg/mL. Based on our findings, culinary-medicinal mushrooms can be considered as potential source of dietary antioxidant and ACE inhibitory agents.

  14. Inhibitory noise

    Directory of Open Access Journals (Sweden)

    Alain Destexhe

    2010-03-01

    Full Text Available Cortical neurons in vivo may operate in high-conductance states, in which the major part of the neuron's input conductance is due to synaptic activity, sometimes several-fold larger than the resting conductance. We examine here the contribution of inhibition in such high-conductance states. At the level of the absolute conductance values, several studies have shown that cortical neurons in vivo are characterized by strong inhibitory conductances. However, conductances are balanced and spiking activity is mostly determined by fluctuations, but not much is known about excitatory and inhibitory contributions to these fluctuations. Models and dynamic-clamp experiments show that, during high-conductance states, spikes are mainly determined by fluctuations of inhibition, or by inhibitory noise. This stands in contrast to low-conductance states, in which excitatory conductances determine spiking activity. To determine these contributions from experimental data, maximum likelihood methods can be designed and applied to intracellular recordings in vivo. Such methods indicate that action potentials are indeed mostly correlated with inhibitory fluctuations in awake animals. These results argue for a determinant role for inhibitory fluctuations in evoking spikes, and do not support feed-forward modes of processing, for which opposite patterns are predicted.

  15. In silico and experimental characterization of chimeric Bacillus thermocatenulatus lipase with the complete conserved pentapeptide of Candida rugosa lipase.

    Science.gov (United States)

    Hosseini, Mostafa; Karkhane, Ali Asghar; Yakhchali, Bagher; Shamsara, Mehdi; Aminzadeh, Saeed; Morshedi, Dena; Haghbeen, Kamahldin; Torktaz, Ibrahim; Karimi, Esmat; Safari, Zahra

    2013-02-01

    Lipases are one of the highest value commercial enzymes as they have broad applications in detergent, food, pharmaceutical, and dairy industries. To provide chimeric Bacillus thermocatenulatus lipase (BTL2), the completely conserved pentapeptide (¹¹²Ala-His-Ser-Gln-Gly¹¹⁶) was replaced with similar sequences (²⁰⁷Gly-Glu-Ser-Ala-Gly²¹¹) of Candida rugosa lipase (CLR) at the nucleophilic elbow region. For this purpose, three mutations including A112G, H113E, and Q115A were inserted in the conserved pentapeptide sequence of btl2 gene. Based on the crystal structures of 2W22, the best structure of opened form of the chimeric lipases were garnered using the MODELLER v9.10 software. The native and chimeric lipases were docked to a set of ligands, and a trial version of Molegro Virtual Docker (MVD) software was used to obtain the energy values. Docking results confirmed chimeric lipase to be better than the native lipase. Following the in silico study, cloning experiments were conducted and expression of native and chimeric btl2 gene in Pichia pastoris was performed. The native and chimeric lipases were purified, and the effect of these mutations on characteristics of chimeric lipase studied and then compared with those of native lipase. Chimeric lipase exhibited 1.6-fold higher activity than the native lipase at 55 °C. The highest percentage of both lipases activity was observed at 60 °C and pH of 8.0. The ion Ca²⁺ slightly inhibited the activity of both lipases, whereas the organic solvent enhanced the lipase stability of chimeric lipase as compared with the native lipase. According to the results, the presence of two glycine residues at the conserved pentapeptide region of this chimeric lipase (¹¹²Gly-Glu-Ser-Ala-Gly¹¹⁶) may increase the flexibility of the nucleophilic elbow region and affect the enzyme activity level.

  16. Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

    Directory of Open Access Journals (Sweden)

    Cornish Marion L

    2007-12-01

    Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

  17. Salvia leriifolia Benth (Lamiaceae) extract demonstrates in vitro antioxidant properties and cholinesterase inhibitory activity.

    Science.gov (United States)

    Loizzo, Monica R; Tundis, Rosa; Conforti, Filomena; Menichini, Federica; Bonesi, Marco; Nadjafi, Farsad; Frega, Natale Giuseppe; Menichini, Francesco

    2010-12-01

    The object of the present study was to investigate the in vitro antioxidant properties and cholinesterase inhibitory activity of Salvia leriifolia Benth extracts and fractions. The functional role of herbs and spices and their constituents is a hot topic in food-related plant research. Salvia species have been used since ancient times in folk medicine for cognitive brain function and have been subjected to extensive research. Thus, we hypothesize that S leriifolia, because of its functional properties, would be a good candidate to use as a nutraceutical product for improving memory in the elderly or patients affected by Alzheimer disease (ad). To test this hypothesis, we examined the cholinesterase inhibitory activity using the modified colorimetric Ellman's method against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The n-hexane exhibited the highest activity, with inhibitory concentration 50% (IC(50)) values of 0.59 and 0.21 mg/mL, for AChE and BChE, respectively. This extract was fractionated, and 9 of these fractions (A-I) were obtained and tested. Fraction G, characterized by the presence of sesquiterpenes as major components, was the most active against AChE (IC(50) = 0.05 mg/mL). Because oxidative stress is a critical event in the pathogenesis of AD, we decided to screen the antioxidant activity (AA) using 2,2-diphenyl-1-picrylhydrazyl test, β-carotene bleaching test, and bovine brain peroxidation (thiobarbituric acid) assay. The ethyl acetate extract showed the highest activity, with IC(50) values of 2 and 33 μg/mL on β-carotene bleaching test and thiobarbituric acid test, respectively. These results suggest potential health benefits of S leriifolia extracts. However, this finding requires additional investigation in vivo.

  18. Triglyceride with medium-chain fatty acids increases the activity and expression of hormone-sensitive lipase in white adipose tissue of C57BL/6J mice.

    Science.gov (United States)

    Liu, Yinghua; Xue, Changyong; Zhang, Yong; Xu, Qing; Yu, Xiaoming; Zhang, Xinsheng; Wang, Jin; Zhang, Rongxin; Gong, Xue; Guo, Changjiang

    2011-01-01

    We have previously shown that medium-chain triglyceride (MCT) resulted in significantly less body fat mass than long-chain triglyceride (LCT) did in hypertriglyceridimic subjects. The possible mechanism for this was investigated by measuring and analyzing changes in the body fat, blood lipid profile, enzymatic level and activity of hormone-sensitive lipase (HSL) and its mRNA expression, and levels of cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) in white adipose tissue (WAT) of C57BL/6J mice fed for 16 weeks on an MCT or LCT diet. MCT induced lower body weight and body fat, and an improved blood lipid profile than LCT did. The enzymatic level and activity of HSL and its mRNA expression, and the levels of cAMP and PKA were significantly higher in WAT of mice fed with the MCT diet. No significant differences in the levels of lipoprotein lipase and peroxisome proliferator-activated receptor-γ in WAT were apparent between the effects of MCT and LCT. It is concluded that lipolysis by the increased level and activity of HSL, which was induced by the activation of cAMP-dependent PKA in WAT, was partially responsible for the lower fat accumulation in C57BL/6J mice fed with MCT.

  19. Activation of hepatic lipase expression by oleic acid: possible involvement of USF1.

    NARCIS (Netherlands)

    D. van Deursen (Diederik); M. van Leeuwen (Marije); D. Akdogan (Deniz); H. Adams (Hadie); H. Jansen (Hans); A.J.M. Verhoeven (Adrie)

    2009-01-01

    textabstractPolyunsaturated fatty acids affect gene expression mainly through peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element binding proteins (SREBPs), but how monounsaturated fatty acids affect gene expression is poorly understood. In HepG2 cells, oleate supplemen

  20. Angiotensin-I-Converting Enzyme Inhibitory and Antioxidant Activities of Protein Hydrolysate from Muscle of Barbel (Barbus callensis)

    OpenAIRE

    Assaad Sila; Anissa Haddar; Oscar Martinez-Alvarez; Ali Bougatef

    2013-01-01

    The present study investigated angiotensin-I-converting enzyme (ACE) inhibitory and antioxidant activities of barbel muscle protein hydrolysate prepared with Alcalase. The barbel muscle protein hydrolysate displayed a high ACE inhibitory activity (C I 50 = 0.92 mg/mL). The antioxidant activities of protein hydrolysate at different concentrations were evaluated using various in vitro antioxidant assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method and reducing power assay. The...

  1. Diagnostic value of post-heparin lipase testing in detecting common genetic variants in the LPL and LIPC genes

    NARCIS (Netherlands)

    M. van Hoek (Mandy); G.M. Dallinga-Thie (Geesje); E.W. Steyerberg (Ewout); E.J.G. Sijbrands (Eric)

    2009-01-01

    textabstractPost-heparin lipoprotein lipase and hepatic lipase activities are used to identify primary disorders of triglyceride and HDL-cholesterol metabolism. Their ability to identify common variants in the lipoprotein lipase (LPL) and hepatic lipase (LIPC) genes is unclear. To investigate the ab

  2. Biochemical characterization of the surface-associated lipase of Staphylococcus saprophyticus.

    Science.gov (United States)

    Sakinç, Türkân; Kleine, Britta; Gatermann, Sören G

    2007-09-01

    Staphylococcus saprophyticus, an important cause of urinary tract infections, produces a surface-associated lipase, Ssp. In contrast to other lipases, Ssp is a protein that is present in high amounts on the surface of the bacteria and it was shown that it is a true lipase. Characterization of S. saprophyticus lipase (Ssp) showed that it is more similar to Staphylococcus aureus lipase and Staphylococcus epidermidis lipase than to Staphylococcus hyicus lipase and Staphylococcus simulans lipase. Ssp showed an optimum of lipolytic activity at pH 6 and lost its activity at pH>8 or pH<5. The present results show that Ssp activity is dependent on Ca(2+). Consequently, activity increased c. 10-fold in the presence of 2 mM Ca(2+). Optimal activity was reached at 30 degrees C. It was also observed that the enzymatic activity of Ssp depends strongly on the acyl chain length of the substrate molecule.

  3. Inhibitory effect of mycoplasma-released arginase. Activity in mixed-lymphocyte and tumour cell cultures

    DEFF Research Database (Denmark)

    Claesson, M H; Tscherning, T; Nissen, Mogens Holst

    1990-01-01

    Non-fermenting mycoplasma species deplete culture media for arginine through arginase activity linked to their arginine deiminase pathway, resulting in proliferation arrest and cell death in mycoplasma-contaminated cell cultures. The presence of only 2-3 Mycoplasma (M.) arginini-contaminated T...... inhibition can be reversed by addition of excess arginine to the culture medium. Antisera raised against non-fermenting, but not against fermenting, mycoplasma species block the inhibitory effect of MAE. SDS-PAGE separation of MAE disclosed a broad band at 60 kDa which contained arginase activity when...

  4. Effect of 6 dietary fatty acids on the postprandial lipid profile, plasma fatty acids, lipoprotein lipase, and cholesterol ester transfer activities in healthy young men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Sandstrøm, B.; Bysted, Anette;

    2001-01-01

    to the test-fat meals were observed for plasma lipoprotein triacylglycerol and cholesterol concentrations, plasma fatty acid concentrations, and lipoprotein lipase and CETP activities (diet x time interaction: 0.001 saturated fatty acids stearic and palmitic acids resulted...... in a relatively lower lipemic response than did intake of the unsaturated fatty acids, probably because the saturated fatty acids were absorbed less and at a lower rate; therefore, the lipemic response took longer to return to postabsorptive values. Conclusions: Fatty acid chain length and degree of saturation...

  5. Placental lipases in pregnancies complicated by gestational diabetes mellitus (GDM.

    Directory of Open Access Journals (Sweden)

    Helen L Barrett

    Full Text Available Infants of women with gestational diabetes mellitus (GDM are more likely to be born large for gestational age with a higher percentage body fat. Elevated maternal lipids may contribute to this. Placental lipases such as lipoprotein lipase (LPL, endothelial lipase (EL and hormone sensitive lipase (HSL are involved in transferring lipids from mother to fetus. Previous studies of expression of these lipases in placentae in women with diabetes in pregnancy have reported divergent results. Intracellular lipases such as adipose triglyceride lipase (ATGL, and HSL are central to lipid droplet metabolism. The activities of these lipases are both influenced by Perilipin 1, and ATGL is also activated by a co-factor comparative gene identification-58 (CGI-58 and inhibited by G0/G1 switch gene 2 (GS02. None of these modifying factors or ATGL have been examined previously in placenta. The purpose of this study was therefore to examine the expression of ATGL, HSL, LPL, EL, as well as Perilipin 1, GS02 and CGI-58 in term pregnancies complicated by GDM. mRNA and protein expression of the lipases were measured in placentae from 17 women with GDM and 17 normoglycaemic pregnancies, matched for maternal BMI and gestational age of delivery. ATGL mRNA expression was increased and HSL mRNA expression reduced in placentae from GDM although there was no differences in protein expression of any of the lipases. All lipases were localised to trophoblasts and endothelial cells. The expression of Perilipin 1 and CGI-58 mRNA was increased and GS02 not altered in GDM. These results suggest that there is no difference in expression in these four lipases between GDM and normoglycaemic placentae, and therefore altered lipid transfer via these lipases does not contribute to large for gestational age in infants of women with GDM.

  6. 棉织物上SESA活化法固定化脂肪酶工艺的研究*%Study on immobilization of lipase onto cotton fiber activated by SESA

    Institute of Scientific and Technical Information of China (English)

    彭立凤; 刘新喜

    2001-01-01

    研究了对-β-硫酸酯乙砜基苯胺活化法在棉织物上固定化脂肪酶的工艺条件,并考察了固定化酶的最适作用温度和pH及间歇操作稳定性。最佳固定化条件为:醚化pH为10.0,偶联pH为7.0,脂肪酶的浓度为6 mg/ml,偶联时间为12h,所得固定化脂肪酶的最大活力为35U/g(棉)·min。固定化酶的最适作用温度为35℃,最适pH为8.0,半衰期为6d。%The conditions of the lipase immobilization onto cotton fiber activated by p-β-sulfuric acid ester ethyl sulfone aniline (SESA) have been studied. The optimal temperature and pH of the immobilized lipase were investigated, and the operating stability of the immobilized lipase was studied too. The results showed that the optimal conditions for the immobilization were that the pH of the reaction for the cotton fiber with SESA was 10.0,the linking pH of lipase to fiber was 7.0,the linking time was 12h,and the concentration of lipase was 6mg· mL- 1 .Then 35 U· g(fiber) - 1 · min- 1 activity of immobilized lipase was obtained. The optimal temperature and pH of the immobilized lipase were 35 ℃ and 8.0 respectively, and its half life was 6 days .

  7. Inhibitory effects of Aphanizomenon flos-aquae constituents on human UDP-glucose dehydrogenase activity.

    Science.gov (United States)

    Scoglio, Stefano; Lo Curcio, Valeria; Catalani, Simona; Palma, Francesco; Battistelli, Serafina; Benedetti, Serena

    2016-12-01

    The purpose of this study was to investigate the in vitro inhibitory effects of the edible microalga Aphanizomenon flos-aquae (AFA) on human UDP-α-d-glucose 6-dehydrogenase (UGDH) activity, a cytosolic enzyme involved both in tumor progression and in phytochemical bioavailability. Both the hydrophilic and ethanolic AFA extracts as well as the constitutive active principles phycocyanin (PC), phycocyanobilin (PCB) and mycosporine-like amino acids (MAAs) were tested. Among AFA components, PCB presented the strongest inhibitory effect on UGDH activity, acting as a competitive inhibitor with respect to UDP-glucose and a non-competitive inhibitor with respect to NAD(+). In preliminary experiments, AFA PCB was also effective in reducing the colony formation capacity of PC-3 prostate cancer cells and FTC-133 thyroid cancer cells. Overall, these findings confirmed that AFA and its active principles are natural compounds with high biological activity. Further studies evaluating the effects of AFA PCB in reducing tumor cell growth and phytochemical glucuronidation are encouraged.

  8. Antibacterial and EGFR-Tyrosine Kinase Inhibitory Activities of Polyhydroxylated Xanthones from Garcinia succifolia

    Directory of Open Access Journals (Sweden)

    Susawat Duangsrisai

    2014-11-01

    Full Text Available Chemical investigation of the methanol extract of the wood of Garcinia succifolia Kurz (Clusiaceae led to the isolation of 1,5-dihydroxyxanthone (1, 1,7-dihydroxyxanthone (2, 1,3,7-trihydroxyxanthone (3, 1,5,6-trihydroxyxanthone (4, 1,6,7-trihydroxyxanthone (5, and 1,3,6,7-tetrahydroxyxanthone (6. All of the isolated xanthones were evaluated for their antibacterial activity against bacterial reference strains, two Gram-positive (Staphylococcus aureus ATTC 25923, Bacillus subtillis ATCC 6633 and two Gram-negative (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853, and environmental drug-resistant isolates (S. aureus B1, Enteroccoccus faecalis W1, and E. coli G1, as well as for their epidermal growth factor receptor (EGFR of tyrosine kinase inhibitory activity. Only 1,5,6-trihydroxy-(4, 1,6,7-trihydroxy-(5, and 1,3,6,7-tetrahydroxyxanthones (6 exhibited antibacterial activity against Gram-positive bacteria, however none was active against vancomycin-resistant E. faecalis. Additionally, 1,7-dihydroxyxanthone (2 showed synergism with oxacillin, but not with ampicillin. On the other hand, only 1,5-dihydroxyxanthone (1 and 1,7-dihydroxyxanthone (2 were found to exhibit the EGFR-tyrosine kinase inhibitory activity, with IC50 values of 90.34 and 223 nM, respectively.

  9. Inhibitory short-term plasticity modulates neuronal activity in the rat entopeduncular nucleus in vitro.

    Science.gov (United States)

    Lavian, Hagar; Korngreen, Alon

    2016-04-01

    The entopeduncular nucleus (EP) is one of the basal ganglia output nuclei integrating synaptic information from several pathways within the basal ganglia. The firing of EP neurons is modulated by two streams of inhibitory synaptic transmission, the direct pathway from the striatum and the indirect pathway from the globus pallidus. These two inhibitory pathways continuously modulate the firing of EP neurons. However, the link between these synaptic inputs to neuronal firing in the EP is unclear. To investigate this input-output transformation we performed whole-cell and perforated-patch recordings from single neurons in the entopeduncular nucleus in rat brain slices during repetitive stimulation of the striatum and the globus pallidus at frequencies within the in vivo activity range of these neurons. These recordings, supplemented by compartmental modelling, showed that GABAergic synapses from the striatum, converging on EP dendrites, display short-term facilitation and that somatic or proximal GABAergic synapses from the globus pallidus show short-term depression. Activation of striatal synapses during low presynaptic activity decreased postsynaptic firing rate by continuously increasing the inter-spike interval. Conversely, activation of pallidal synapses significantly affected postsynaptic firing during high presynaptic activity. Our data thus suggest that low-frequency striatal output may be encoded as progressive phase shifts in downstream nuclei of the basal ganglia while high-frequency pallidal output may continuously modulate EP firing.

  10. Screening of plants containing Naja naja siamensis cobra venom inhibitory activity using modified ELISA technique.

    Science.gov (United States)

    Daduang, Sakda; Sattayasai, Nison; Sattayasai, Jintana; Tophrom, Pattara; Thammathaworn, Achra; Chaveerach, Arunrat; Konkchaiyaphum, Monruedee

    2005-06-15

    Enzyme-linked immunosorbent assay (ELISA) has been modified for screening plants with antagonistic activity to Naja naja siamensis cobra venom. Aqueous extracts from plants were investigated for their inhibitory effects on the binding of anti-cobra venom antibody to antigen, cobra venom, fixed onto 96-well microtiter plates. Ingredients in extracts were allowed to react with immobilized venom before the subsequent addition of antivenom antibody. Venom components affected by exposure to the extracts, unable to interact with their specific antibody, were predicted to be unable to bind to their native destinations or natural receptors. Curcuma cf. zedoaria, an old Thai medicinal plant, showed clear inhibitory activity in the ELISA test. Neurotoxin and protein degradative enzymes, major components in venom, were identified as targets of this extract in Western immunoblotting analysis. Ingredients in the extract showed high affinity to the toxin in competition assay by immunoprecipitation. The extract attenuated toxin activity by extending contraction time of diaphragm muscle after envenomation and had a potency to protect cellular proteins from venom degradative enzymes. Curcuma parviflora, with less activity in ELISA, exhibited acceptable results in two experiments but negative results in two experiments, whereas Curcuma longa, having low activity in the ELISA test, never showed any favorable results. Screening of 36 samples could classify plants into an inhibition range of 0 to 86%. This modified ELISA is recommended as a preliminary screening method for inhibitors with a large number of samples.

  11. Anti-inflammatory, cyclooxygenase inhibitory and antioxidant activities of standardized extracts of Tridax procumbens L.

    Science.gov (United States)

    Jachak, Sanjay M; Gautam, Raju; Selvam, C; Madhan, Himanshu; Srivastava, Amit; Khan, Taj

    2011-03-01

    The standardized EtOAc, MeOH and 70% EtOH extracts of Tridax procumbens aerial parts showed significant inhibition of rat paw edema at a medium dose of 200mg/kg and the EtOAC extract was the most active. These extracts were standardized by HPLC with the help of chemical markers. Further, the extracts were evaluated for COX-1 and COX-2 inhibitory activity and EtOAc extract exhibited the highest inhibition of COX-1 and COX-2 at 50 μg/mL. Cent aurein, centaureidin and bergenin were isolated as COX-1 and COX-2 inhibitory principles from the EtOAc extract. The extracts also exhibited antioxidant activity against DPPH and ABTS free radicals. The anti-inflammatory activity of T. procumbens aerial parts could be at least in part due to COX-1, COX-2 enzyme inhibition and free radical-scavenging activities which may be attributed to the presence of flavonoids and other polyphenols in the extracts.

  12. A Subtype of Inhibitory Interneuron with Intrinsic Persistent Activity in Human and Monkey Neocortex

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2015-03-01

    Full Text Available A critical step in understanding the neural basis of human cognitive functions is to identify neuronal types in the neocortex. In this study, we performed whole-cell recording from human cortical slices and found a distinct subpopulation of neurons with intrinsic persistent activity that could be triggered by single action potentials (APs but terminated by bursts of APs. This persistent activity was associated with a depolarizing plateau potential induced by the activation of a persistent Na+ current. Single-cell RT-PCR revealed that these neurons were inhibitory interneurons. This type of neuron was found in different cortical regions, including temporal, frontal, occipital, and parietal cortices in human and also in frontal and temporal lobes of nonhuman primate but not in rat cortical tissues, suggesting that it could be unique to primates. The characteristic persistent activity in these inhibitory interneurons may contribute to the regulation of pyramidal cell activity and participate in cortical processing.

  13. ACE-inhibitory activity of enzymatic protein hydrolysates from lupin and other legumes.

    Science.gov (United States)

    Boschin, Giovanna; Scigliuolo, Graziana Maria; Resta, Donatella; Arnoldi, Anna

    2014-02-15

    The objective of this investigation was to compare the angiotensin converting enzyme (ACE)-inhibitory activity of the hydrolysates obtained by pepsin digestion of proteins of some legumes, such as chickpea, common bean, lentil, lupin, pea, and soybean, by using the same experimental procedure. The ACE-inhibitory activity was measured by using the tripeptide hippuryl-histidyl-leucine (HHL), as model peptide, and HPLC-DAD, as analytical method. The peptide mixtures of all legumes were active, with soybean and lupin the most efficient, with IC50 values of 224 and 226 μg/ml, respectively. Considering the promising results obtained with lupin, and aiming to identify the protein(s) that release(s) the peptides responsible for the activity, the peptides obtained from the pepsin digestion of some industrial lupin protein isolates and purified protein fractions were tested. The most active mixture, showing an IC50 value of 138 μg/ml, was obtained hydrolysing a mixture of lupin α+β conglutin.

  14. Lipoprotein lipase activity and interactions studied in human plasma by isothermal titration calorimetry.

    Science.gov (United States)

    Reimund, Mart; Kovrov, Oleg; Olivecrona, Gunilla; Lookene, Aivar

    2017-01-01

    LPL hydrolyzes triglycerides in plasma lipoproteins. Due to the complex regulation mechanism, it has been difficult to mimic the physiological conditions under which LPL acts in vitro. We demonstrate that isothermal titration calorimetry (ITC), using human plasma as substrate, overcomes several limitations of previously used techniques. The high sensitivity of ITC allows continuous recording of the heat released during hydrolysis. Both initial rates and kinetics for complete hydrolysis of plasma lipids can be studied. The heat rate was shown to correspond to the release of fatty acids and was linearly related to the amount of added enzyme, either purified LPL or postheparin plasma. Addition of apoC-III reduced the initial rate of hydrolysis by LPL, but the inhibition became less prominent with time when the lipoproteins were triglyceride poor. Addition of angiopoietin-like protein (ANGPTL)3 or ANGPTL4 caused reduction of the activity of LPL via a two-step mechanism. We conclude that ITC can be used for quantitative measurements of LPL activity and interactions under in vivo-like conditions, for comparisons of the properties of plasma samples from patients and control subjects as substrates for LPL, as well as for testing of drug candidates developed with the aim to affect the LPL system. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  15. Stability of immobilized candida sp. 99-125 Lipase for biodiesel production

    Energy Technology Data Exchange (ETDEWEB)

    Lu, J. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China); Bioengineering Department, Zhengzhou University, Zhengzhou (China); Deng, L.; Nie, K.; Wang, F.; Tan, T. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China)

    2012-12-15

    The stability of the immobilized lipase from Candida sp. 99-125 during biodiesel production was investigated. The lipase was separately incubated in the presence of various reaction components such as soybean oil, oleic acid methyl ester, n-hexane, water, methanol, and glycerol, or the lipase was stored at 60, 80, 100 and 120 C. Thereafter the residual lipase activity was determined by methanolysis reaction. The results showed that the lipase was rather stable in the reaction media, except for methanol and glycerol. The stability study performed in a reciprocal shaker indicated that enzyme desorption from the immobilized lipase mainly contributed to the lipase inactivation in the water system. So the methanol and glycerol contents should be controlled more precisely to avoid lipase inactivation, and the immobilization method should be improved with regard to lipase desorption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Screening Pancreatic Lipase Inhibitors from Fruits and Vegetables%果蔬源胰脂肪酶抑制剂的筛选

    Institute of Scientific and Technical Information of China (English)

    刘蕊; 张景照; 郑毅男; 徐宝军; 刘文丛

    2012-01-01

    The objective was to evaluate the anti-obesity effects of ethanol extracts of 30 kinds of fruits and vegetables. The authors investigated their inhibitory activity against pancreatic lipase by determining the release of oleic acid from triolein. The results showed that ethanol extract of green pepper exhibited the strongest pancreatic lipase inhibitory activity and the inhibition rate was 46.15 % . The anti-lipase activity of mangosteen extract was in the second. In addition, the pancreatic lipase inhibition rate of white radish, lemon and small tomato extract exceeded 20% . However, garlic, hawthorn and orange peel extract enhanced the pancreatic lipase activity. Their pancreatic lipase promotion rates were 29.64%, 7.66% and 6.38% , respectively. It is demonstrated that some fruits and vegetables extracts have the inhibitory effects against pancreatic lipase. The results provided strong theoretical basis for further investigating the inhibitory mechanism in vitro and in vivo.%通过从三油酸甘油酯释放油酸的释放率来判定胰脂肪酶活性的方法,研究并比较了30种果蔬乙醇提取物的减肥作用.30种果蔬70%乙醇提取物对胰脂肪酶作用的测定结果表明:青辣椒乙醇提取物对胰脂肪酶的抑制作用最强,抑制率为46.15%,山竹提取物抑制率为29.87%,白萝卜、柠檬和圣女果提取物对胰脂肪酶的抑制率均达到20%以上.大蒜提取物对胰脂肪酶有较强的促进作用(29.64%),陈皮和山楂提取物对胰脂肪酶的促进率分别为6.38%和7.66%.

  17. Anti- and Pro-Lipase Activity of Selected Medicinal, Herbal and Aquatic Plants, and Structure Elucidation of an Anti-Lipase Compound

    OpenAIRE

    2013-01-01

    Plants that help in slowing down the digestion of triacylglycerols (TAGs) in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98) medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine...

  18. Immobilization of Lipase by Covalent Binding on Crosslinked Ally Dextran

    Institute of Scientific and Technical Information of China (English)

    WangChen; SongGuoqiang; 等

    1998-01-01

    Lipase was immobilized by covalent binding on crosslinked allyl dextran using SESA as coupling agent.It is shown that this immobilization approach is an efficient one for lipase.The activity of the immobilized lipase can reach to 300-450U/g(dry weight).It exhibits good temperature stability,can retain 88% activity after being incubated at 70℃ for 2h.Special effects will be expected from our immobilized lipase in its applications in organic media due to the nature of the support.

  19. Synthesis of Triazole Schiff's Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity.

    Directory of Open Access Journals (Sweden)

    Feng Yu

    Full Text Available In the present study, new Schiff's base derivatives: (Z-4-amino-5-(2-(3- fluorobenzylidenehydrazinyl-4H-1,2,4-triazole-3-thiol (Y1, (Z-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-ylhydrazonomethylphenol (Y2, (Z-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-ylhydrazonomethylphenol (Y3 and 3-((Z-(2-(4- (((E-3-hydroxybenzylideneamino-5-mercapto-4H-1,2,4-triazol-3-ylhydrazonomethylphenol (Y4 were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents.

  20. Fc gamma receptor CD64 modulates the inhibitory activity of infliximab.

    Directory of Open Access Journals (Sweden)

    Kacper A Wojtal

    Full Text Available BACKGROUND: Tumor necrosis factor (TNF is an important cytokine in the pathogenesis of inflammatory bowel disease (IBD. Anti-TNF antibodies have been successfully implemented in IBD therapy, however their efficacies differ among IBD patients. Here we investigate the influence of CD64 Fc receptor on the inhibitory activity of anti-TNFs in cells of intestinal wall. METHODS: Intestinal cell lines, monocytes/macrophages and peripheral blood mononuclear cells (PBMCs were used as models. The efficacies of adalimumab, infliximab and certolizumab-pegol were assessed by RT-PCR for target genes. Protein levels and localizations were examined by Western blotting and immunofluorescence. Antibody fragments were obtained by proteolytic digestion, immunoprecipitation and protein chip analysis. Knock-down of specific gene expression was performed using siRNAs. RESULTS: Infliximab had limited efficacy towards soluble TNF in cell types expressing Fc gamma receptor CD64. Both adalimumab and infliximab had lower efficacies in PBMCs of IBD patients, which express elevated levels of CD64. Infliximab-TNF complexes were more potent in activating CD64 in THP-1 cells than adalimumab, which was accompanied by distinct phospho-tyrosine signals. Blocking Fc parts and isolation of Fab fragments of infliximab improved its efficacy. IFN-γ-induced expression of CD64 correlated with a loss of efficacy of infliximab, whereas reduction of CD64 expression by either siRNA or PMA treatment improved inhibitory activity of this drug. Colonic mRNA expression levels of CD64 and other Fc gamma receptors were significantly increased in the inflamed tissues of infliximab non-responders. CONCLUSIONS: CD64 modulates the efficacy of infliximab both in vitro and ex vivo, whereas the presence of this receptor has no impact on the inhibitory activity of certolizumab-pegol, which lacks Fc fragment. These data could be helpful in both predicting and evaluating the outcome of anti-TNF therapy in

  1. Immobilization of lipase from Fusarium solani FS1 Imobilização de lipase de Fusarium solani FS1

    Directory of Open Access Journals (Sweden)

    Kirsty Knight

    2000-09-01

    Full Text Available Lipase from Fusarium solani FS1 was immobilized by covalent attachment to polyacrylamide beads and onto magnetized Dacron, retaining 12% and 97% of activity, respectively. Lipase was also entrapped within polyacrylamide beads, retaining 53% of activity. Investigations of the kinetic characteristics of the immobilized derivatives using triolein as substrate showed that lipase immobilized onto polyacrilamide beads and Dacron did not follow Michaelis-Menten kinetics.Lipase de Fusarium solani FS1 foi imobilizada por ligação covalente usando esferas de poliacrilamida e Dacron magnetizado, retendo 12%, e 97% de atividade, respectivamente. A lipase foi também enclausurada em esferas de poliacrilamida e reteve 53% de sua atividade específica. Investigações sobre o comportamento cinético usando trioleína como substrato mostraram que as lipases imobilizadas não seguem a cinética de Michaelis-Menten.

  2. Expression and Mutagenesis studies of Candida antactica lipase B

    OpenAIRE

    Rotticci-Mulder, Johanna C.

    2003-01-01

    Recombinant Candida antarctica lipase B was successfullyproduced in the methylotropic yeast Pichia pastoris. Thespecific activities of Candida antarctica lipase B produced inPichia pastoris and commercial Candida antarctica lipase B fromNovozymes were the same. In shake-flask cultivations theexpression levels were about 25 mg L-1. Production levels couldbe increased to 1.5 g L-1, using a fermentor. A model tosimulate growth and oxygen consumption was described. The highcell density growth cou...

  3. Pressure stability of lipases and their use in different systems

    OpenAIRE

    Knez, Željko; Leitgeb, Maja

    2015-01-01

    For the investigation of the solvent impact on the enzymes, lipases from different sources (Pseudomonas fluorescences, Rhizopus javanicus, Rhizopus niveus, Candida rugose and Porcine pancreas) were used. Stability and activity of these lipases in aqueous medium in supercritical $CO_2$ and liquid propane at 100 bar and 40°C were studied. On the basis of previous results lipases were used for their application in two different systems. The application of the polysulphone membrane in the cont...

  4. In vitro screening of Crataegus succulenta extracts for free radical scavenging and 15-lipoxygenase inhibitory activities.

    Science.gov (United States)

    Bedreag, Catrinel Florentina Giurescu; Trifan, Adriana; Vasincu, Al; Miron, S D; Aprotosoaie, Ana Clara; Miron, Anca

    2014-01-01

    Crataegus succulenta Schrad. ex Link is widely spread in North America. A literature survey revealed no studies on the chemical composition and biological effects of this species. The aim of the present study was to investigate the phenolic content, free radical scavenging and 15-lipoxygenase inhibitory effects of Crataegus succulenta leaf and flower extracts. Total phenolic, flavonoid and proanthocyanidin contents were quantified by spectrophotometric methods. Both extracts were evaluated for their ability to scavenge DPPH, superoxide anion and hydroxyl radicals and to inhibit 15-lipoxygenase activity. There were noticed no striking differences in the total phenolic, flavonoid and proanthocyanidin contents between leaf and flower extracts. Both extracts showed similar 15-lipoxygenase inhibitory effects. Flower extract scavenged more effectively DPPH and superoxide radicals while leave extract was more active against hydroxyl radical. In superoxide anion radical scavenging assay, both extracts were more active than (+)-catechin. In hydroxyl radical scavenging and 15-lipoxygenase inhibition assays, the extracts were only 4-5 times less active than (+)-catechin. The high antioxidant potential of Crataegus succulenta extracts suggest a possible use as ingredients in functional foods for the prevention of oxidative stress-related diseases.

  5. Nanocapsular Dispersion of Cinnamaldehyde for Enhanced Inhibitory Activity against Aflatoxin Production by Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Hongbo Li

    2015-04-01

    Full Text Available Cinnamaldehyde (CA is marginally soluble in water, making it challenging to evenly disperse it in foods, and resulting in lowered anti-A. flavus efficacy. In the present study, nano-dispersed CA (nano-CA was prepared to increase its aqueous solubility. Free and nano-dispersed CA were compared in terms of their inhibitory activity against fungal growth and aflatoxin production of A. flavus both in Sabouraud Dextrose (SD culture and in peanut butter. Our results indicated that free CA inhibited the mycelia growth and aflatoxin production of A. flavus with a minimal inhibitory concentration (MIC value of 1.0 mM, but promoted the aflatoxin production at some concentrations lower than the MIC. Nano-CA had a lower MIC value of 0.8 mM against A. flavus, and also showed improved activity against aflatoxin production without the promotion at lower dose. The solidity of peanut butter had an adverse impact on the antifungal activity of free CA, whereas nano-dispersed CA showed more than 2-fold improved activity against the growth of A. flavus. Free CA still promoted AFB1 production at the concentration of 0.25 mM, whereas nano-CA showed more efficient inhibition of AFB1 production in the butter.

  6. Structures and antioxidant and intestinal disaccharidase inhibitory activities of A-type proanthocyanidins from peanut skin.

    Science.gov (United States)

    Zhang, Huiwen; Yerigui; Yang, Yumei; Ma, Chaomei

    2013-09-18

    Nine compounds including a new A-type proanthocyanidin trimer, epicatechin-(2β→O→7,4β→8)-[catechin-(6→4β)]-epicatechin (8), and a known trimer, epicatechin-(4β→8)-epicatechin-(2β→O→7,4β→8)-catechin (9), being reported for peanut skin for the first time, were isolated and purified. Their structures were determined by spectroscopic methods and by degradation reactions with L-cysteine in acidic conditions. The DPPH radical scavenging activity and the inhibitory activity on maltase and sucrase of the isolated compounds were investigated. All compounds showed strong DPPH scavenging activities (EC₅₀ < 20 μg/mL). Compound 8 showed the strongest inhibitory activity on maltase with an IC₅₀ value of 0.088 mg/mL, while compound 9 exhibited the strongest inhibition on sucrase with an IC₅₀ value of 0.091 mg/mL.

  7. Selection of potentially probiotic Lactobacillus strains towards their inhibitory activity against poultry enteropathogenic bacteria.

    Science.gov (United States)

    Kizerwetter-Swida, Magdalena; Binek, Marian

    2005-01-01

    Lactobacilli were isolated from chicken gastrointestinal tract and examined for their potentially probiotic properties towards their inhibitory activity against poultry enteropathogenic bacteria. Biochemical tests, ITS-PCR and cell wall protein analysis were used to characterize the Lactobacillus isolates. The identification of isolated Lactobacillus strains based on phenotypic properties was not always satisfactory. ITS-PCR together with protein profile were found to be helpful in strain identification. Lactobacilli were tested for the inhibitory activity against selected strains of poultry enteropathogenic bacteria (Salmonella Enteritidis, Escherichia coli and Clostridium perfringens). Examined supernatants from Lactobacillus broth cultures demonstrated major antimicrobial activity against C. perfringens. Lower antimicrobial activity were observed against E. coli and Salmonella Enteritidis. The strongest inhibition effect were obtained using supernatant of Lactobacillus acidophilus strain 3D. Results received from this study confirmed that identification of Lactobacillus spp. is often tedious. Some isolates, which are in vitro antagonistic against enteropathogenic bacteria may be considered as potential candidates for poultry probiotics, especially in controlling necrotic enteritis caused by C. perfringens.

  8. α-Glucosidase inhibitory activity and cytotoxic effects of some cyclic urea and carbamate derivatives.

    Science.gov (United States)

    Popović-Djordjević, Jelena B; Jevtić, Ivana I; Grozdanić, Nadja Dj; Šegan, Sandra B; Zlatović, Mario V; Ivanović, Milovan D; Stanojković, Tatjana P

    2017-12-01

    The inhibitory activities of selected cyclic urea and carbamate derivatives (1-13) toward α-glucosidase (α-Gls) in in vitro assay were examined in this study. All examined compounds showed higher inhibitory activity (IC50) against α-Gls compared to standard antidiabetic drug acarbose. The most potent was benzyl (3,4,5-trimethoxyphenyl)carbamate (12) with IC50 = 49.85 ± 0.10 µM. In vitro cytotoxicity of the investigated compounds was tested on three human cancer cell lines HeLa, A549 and MDA-MB-453 using MTT assay. The best antitumour activity was achieved with compound 2 (trans-5-phenethyl-1-phenylhexahydro-1H-imidazo[4,5-c]pyridin-2(3H)-one) against MDA-MB-453 human breast cancer cell line (IC50 = 83.41 ± 1.60 µM). Cyclic ureas and carbamates showed promising anti-α-glucosidase activity and should be further tested as potential antidiabetic drugs. The PLS model of preliminary QSAR study indicated that, in planing the future synthesis of more potent compounds, the newly designed should have the substituents capable of polar interactions with receptor sites in various positions, while avoiding the increase of their lipophilicity.

  9. An activating and inhibitory signal from an inhibitory receptor LMIR3/CLM-1: LMIR3 augments lipopolysaccharide response through association with FcRgamma in mast cells.

    Science.gov (United States)

    Izawa, Kumi; Kitaura, Jiro; Yamanishi, Yoshinori; Matsuoka, Takayuki; Kaitani, Ayako; Sugiuchi, Masahiro; Takahashi, Mariko; Maehara, Akie; Enomoto, Yutaka; Oki, Toshihiko; Takai, Toshiyuki; Kitamura, Toshio

    2009-07-15

    Leukocyte mono-Ig-like receptor 3 (LMIR3) is an inhibitory receptor mainly expressed in myeloid cells. Coengagement of Fc epsilonRI and LMIR3 impaired cytokine production in bone marrow-derived mast cells (BMMCs) induced by Fc epsilonRI crosslinking alone. Mouse LMIR3 possesses five cytoplasmic tyrosine residues (Y241, Y276, Y289, Y303, Y325), among which Y241 and Y289 (Y241/289) or Y325 fit the consensus sequence of ITIM or immunotyrosine-based switch motif (ITSM), respectively. The inhibitory effect was abolished by the replacement of Y325 in addition to Y241/289 with phenylalanine (Y241/189/325/F) in accordance with the potential of Y241/289/325 to cooperatively recruit Src homology region 2 domain-containing phosphatase 1 (SHP)-1 or SHP-2. Intriguingly, LMIR3 crosslinking alone induced cytokine production in BMMCs expressing LMIR3 (Y241/276/289/303/325F) mutant as well as LMIR3 (Y241/289/325F). Moreover, coimmunoprecipitation experiments revealed that LMIR3 associated with ITAM-containing FcRgamma. Analysis of FcRgamma-deficient BMMCs demonstrated that both Y276/303 and FcRgamma played a critical role in the activating function of this inhibitory receptor. Importantly, LMIR3 crosslinking enhanced cytokine production of BMMCs stimulated by LPS, while suppressing production stimulated by other TLR agonists or stem cell factor. Thus, an inhibitory receptor LMIR3 has a unique property to associate with FcRgamma and thereby functions as an activating receptor in concert with TLR4 stimulation.

  10. Activity-dependent transmission and integration control the timescales of auditory processing at an inhibitory synapse.

    Science.gov (United States)

    Ammer, Julian J; Siveke, Ida; Felmy, Felix

    2015-06-15

    To capture the context of sensory information, neural networks must process input signals across multiple timescales. In the auditory system, a prominent change in temporal processing takes place at an inhibitory GABAergic synapse in the dorsal nucleus of the lateral lemniscus (DNLL). At this synapse, inhibition outlasts the stimulus by tens of milliseconds, such that it suppresses responses to lagging sounds, and is therefore implicated in echo suppression. Here, we untangle the cellular basis of this inhibition. We demonstrate with in vivo whole-cell patch-clamp recordings in Mongolian gerbils that the duration of inhibition increases with sound intensity. Activity-dependent spillover and asynchronous release translate the high presynaptic firing rates found in vivo into a prolonged synaptic output in acute slice recordings. A key mechanism controlling the inhibitory time course is the passive integration of the hyperpolarizing inhibitory conductance. This prolongation depends on the synaptic conductance amplitude. Computational modeling shows that this prolongation is a general mechanism and relies on a non-linear effect caused by synaptic conductance saturation when approaching the GABA reversal potential. The resulting hyperpolarization generates an efficient activity-dependent suppression of action potentials without affecting the threshold or gain of the input-output function. Taken together, the GABAergic inhibition in the DNLL is adjusted to the physiologically relevant duration by passive integration of inhibition with activity-dependent synaptic kinetics. This change in processing timescale combined with the reciprocal connectivity between the DNLLs implements a mechanism to suppress the distracting localization cues of echoes and helps to localize the initial sound source reliably.

  11. Attachment of Lipase on Amino Functionalized Titania Submicrospheres via Covalent Binding

    Institute of Scientific and Technical Information of China (English)

    WU Hong; LIANG Yan-peng; SHI Jia-fu; WANG Xiao-li

    2013-01-01

    A facile and effective method for immobilized lipase was presented.The titania submicrospheres were synthesized via a modified sol-gel method followed by amino functionalization through the chelation between dopamine and titania.Lipase was covalently attached on the functionalized titania surface using glutaraldehyde as the cross linking agent.The loading ratio and relative activity of the immobilized lipase were 230 mg/g titania submicrospheres and 65%,respectively.The kinetic parameters including the Michaelis constant (Km) and the maximum reaction rate (Vmax) changed slightly after immobilization.Compared to free lipase,the immobilized lipase showed favorable pH stability,thermostability,recycling stability and storage stability.The immobilized lipase retained 90% activity after incubation at 50 ℃ for 2 h,while the free lipase retained only 60% activity.The immobilized lipase retained more than 80% activity after 8 batches.

  12. Silk-Cocoon Matrix Immobilized Lipase Catalyzed Transesterification of Sunflower Oil for Production of Biodiesel

    OpenAIRE

    Sushovan Chatterjee; Dipti Yadav; Lepakshi Barbora; Pinakeswar Mahanta; Pranab Goswami

    2014-01-01

    Biodiesel from sunflower oil using lipase chemically immobilized on silk-cocoon matrix in a packed-bed bioreactor was investigated. The immobilization was demonstrated by field-emission scanning electron microscopy and activity study. The lipase loading was 738.74 U (~0.01 g lipase powder)/g-lipase-immobilized matrix. The Km (Michaelis-Menten constant) of the free and the immobilized lipase was 451.26 μM and 257.26 μM, respectively. Low Km value of the immobilized lipase is attributed to the ...

  13. Synthesis and in vitro growth inhibitory activity of novel silyl- and trityl-modified nucleosides

    CSIR Research Space (South Africa)

    Panayides, Jenny-Lee

    2016-06-01

    Full Text Available -Farkas d, Hajierah Davids d,e , Leonie Harmse d , M. E. Christine Rey f , Ivan R. Green g, Stephen C. Pelly g, Robert Kiss c, Alexander Kornienko h, Willem A. L. van Otterlo a,g,⇑ a Molecular Sciences Institute, School of Chemistry, University... & Medicinal Chemistry 24 (2016) 2716–2724 Synthesis and in vitro growth inhibitory activity of novel silyl- and trityl-modified nucleosides Jenny-Lee Panayides a,b, Véronique Mathieu c, Laetitia Moreno Y. Banuls c, Helen Apostolellis d, Nurit Dahan...

  14. Nitric oxide inhibitory activity of monogalactosylmonoacylglycerols from a freshwater microalgae Chlorella sorokiniana.

    Science.gov (United States)

    Banskota, Arjun H; Stefanova, Roumiana; Gallant, Pamela; Osborne, Jane A; Melanson, Ronald; O'Leary, Stephen J B

    2013-01-01

    Chemical investigation of the freshwater microalgae Chlorella sorokiniana led to the isolation of a new monogalactosylmonoacylglycerol, namely, (2S)-1-O-(7Z,10Z-hexadecadienoyl)-3-O-β-D-galactopyranosylglycerol (1) together with a known glycolipid (2S)-1-O-(7Z,10Z,13Z-hexadecatrienoyl)-3-O-β-D-galactopyranosylglycerol (2). Both monogalactosylmonoacylglycerols showed dose-dependent nitric oxide (NO) inhibitory activity against lipopolysaccharide-induced NO production in RAW264.7 macrophage cells suggesting their possible use as anti-inflammatory agents.

  15. A New Synthesis Method and GABA Transporters Inhibitory Activities of Tiagabine and Its Analogues

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new synthetic method and GABA transporter inhibitory activities of Tiagabine and its analogues are described.The key intermediates 4-tosyl-1,1-diaryl/heteroaryl-1-butene 10a-10e were synthesized by Wittig reaction, and followed by N-alkylation with (R)-3-piperidinecarboxylate. The resultingN-diheterocyclylalkenylpiperidine-3-carboxylic acid ester 11a-11e were saponified and then acidified toget the target compounds 1a-1e. The preliminary bioassays show that compound 1a-1e exhibited excellent inhibition of [3H]-GABA uptake in vitro of culture cells.

  16. Isolation of inhibitory factor in raw milk whey active against propionibacteria.

    Science.gov (United States)

    Vedamuthu, E R; Washam, C J; Reinbold, G W

    1971-10-01

    Preparative isolation of the active component(s) in skim milk whey inhibitory for propionibacteria was made by using (NH(4))(2)SO(4) salt fractionation. The crude preparation was further purified by Sephadex G-100 column separation. Disc-gel electrophoresis of the active peak from the Sephadex elution pattern (peak I) showed that this fraction contained almost all of the immune globulin in the column sample. The biologically inactive peaks did not contain any immune globulin. Starch-gel electrophoresis of the active peak revealed the presence of three separate immune globulin fractions. A correlation was also observed between hemolytic reaction of propionibacterial strains and relative resistance to whey inhibition. The investigation showed that one of the immune globulins of milk, pseudoglobulin, was mainly responsible for the suppressive activity of whey.

  17. Inhibitory activity of Iranian plant extracts on growth and biofilm formation by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Mansouri, S.

    2013-01-01

    Full Text Available Aims: Pseudomonas aeruginosa is a drug resistance opportunistic bacterium. Biofilm formation is key factor for survivalof P. aeruginosa in various environments. Polysaccharides may be involved in biofilm formation. The purpose of thisstudy was to evaluate antimicrobial and anti-biofilm activities of seven plant extracts with known alpha-glucosidaseinhibitory activities on different strains of P. aeruginosa.Methodology and results: Plants were extracted with methanol by the maceration method. Antimicrobial activities weredetermined by agar dilution and by growth yield as measured by OD560nm of the Luria Bertani broth (LB culture with orwithout extracts. In agar dilution method, extracts of Quercus infectoria inhibited the growth of all, while Myrtuscommunis extract inhibited the growth of 3 out of 8 bacterial strains with minimum inhibitory concentration (MIC of 1000μg/mL. All extracts significantly (p≤0.003 reduced growth rate of the bacteria in comparison with the control withoutextracts in LB broth at sub-MIC concentrations (500 μg/mL. All plant extracts significantly (p≤0.003 reduced biofilmformation compared to the controls. Glycyrrhiza glabra and Q. infectoria had the highest anti-biofilm activities. Nocorrelation between the alpha-glucosidase inhibitory activity with growth or the intensity of biofilm formation was found.Conclusion, significance and impact of study: Extracts of Q. infectoria and M. communis had the most antimicrobial,while Q. infectoria and G. glabra had the highest anti-biofilm activities. All plant extracts had anti-biofilm activities withmarginal effect on growth, suggesting that the mechanisms of these activities are unrelated to static or cidal effects.Further work to understand the relation between antimicrobial and biofilm formation is needed for development of newmeans to fight the infectious caused by this bacterium in future.

  18. Dependency of water concentration on ethanolysis of trioleoylglycerol by lipases

    DEFF Research Database (Denmark)

    Piyatheerawong, W.; Iwasaki, Y; Xu, Xuebing

    2004-01-01

    The effects of water concentration on ethanolysis of trioleoylglycerol catalyzed by four different lipases were studied. The target product of the ethanolysis was 2-monooleoylglycerol (2-MO). Novozym 435 (a commercially available preparation of immobilized Candida antarctica lipase B, CALB......) exhibited both the highest product yield and the reaction rate at very low (less than 1 wt.%) free water concentration. Its catalytic activity did not drop even in dry state, i.e. in the system of dry CALB in dry ethanol (water concentration was ca. 0.1 wt.%). In contrast, other three immobilized lipases...... tested (Rhizomucor miehei lipase, Burkholderia cepacia lipase and Thermomyces lanuginosus lipase) required larger amounts of free water (ca. 7-9 wt.%) for their best performance and exhibited no ethanolysis reaction at low free water concentrations. The CALB's anomalous behavior was also observed...

  19. Lactobacillus crispatus dominant vaginal microbiome is associated with inhibitory activity of female genital tract secretions against Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Jeny P Ghartey

    Full Text Available OBJECTIVE: Female genital tract secretions inhibit E. coli ex vivo and the activity may prevent colonization and provide a biomarker of a healthy microbiome. We hypothesized that high E. coli inhibitory activity would be associated with a Lactobacillus crispatus and/or jensenii dominant microbiome and differ from that of women with low inhibitory activity. STUDY DESIGN: Vaginal swab cell pellets from 20 samples previously obtained in a cross-sectional study of near-term pregnant and non-pregnant healthy women were selected based on having high (>90% inhibition or low (<20% inhibition anti-E. coli activity. The V6 region of the 16S ribosomal RNA gene was amplified and sequenced using the Illumina HiSeq 2000 platform. Filtered culture supernatants from Lactobacillus crispatus, Lactobacillus iners, and Gardnerella vaginalis were also assayed for E. coli inhibitory activity. RESULTS: Sixteen samples (10 with high and 6 with low activity yielded evaluable microbiome data. There was no difference in the predominant microbiome species in pregnant compared to non-pregnant women (n = 8 each. However, there were significant differences between women with high compared to low E. coli inhibitory activity. High activity was associated with a predominance of L. crispatus (p<0.007 and culture supernatants from L. crispatus exhibited greater E. coli inhibitory activity compared to supernatants obtained from L. iners or G. vaginalis. Notably, the E. coli inhibitory activity varied among different strains of L. crispatus. CONCLUSION: Microbiome communities with abundant L. crispatus likely contribute to the E. coli inhibitory activity of vaginal secretions and efforts to promote this environment may prevent E. coli colonization and related sequelae including preterm birth.

  20. 5 Alpha-reductase inhibitory and antiandrogenic activities of novel steroids in hamster seminal vesicles.

    Science.gov (United States)

    Cabeza, Marisa; Bratoeff, Eugene; Flores, Eugenio; Ramírez, Elena; Calleros, Jorge; Montes, Diana; Quiroz, Alexandra; Heuze, Ivonne

    2002-11-01

    The pharmacological activity of several 16-bromosubstituted trienediones 4 and 5, 16-methyl substituted dienediones 6 and 7 and the 16-methyl substituted trienedione 8 was determined on gonadectomized hamster seminal vesicles by measuring the in vitro conversion of testosterone (T) to dihydrotestosterone (DHT) as 5alpha-reductase inhibitors and also the ability of these steroids to bind to the androgen receptor. Steroids 6 and 7 when injected together with T decreased the weight of the seminal vesicles thus showing an antiandrogenic effect. Compounds 5 and 6 reduced substantially the conversion of T to DHT and therefore can be considered good inhibitors for the enzyme 5alpha-reductase; however both steroids failed to form a complex with the androgen receptor. On the other hand compound 7 which showed a very small inhibitory activity for the enzyme 5alpha-reductase, exhibited a very high affinity for the androgen receptor and thus can be considered an effective antiandrogen. This compound also reduced substantially the weight of the seminal vesicles. Steroids 4 and 8 did not reduce the weight of the seminal vesicles and exhibited a low affinity for the androgen receptor; 8 showed a weak 5alpha-reductase inhibitory activity, whereas 4 exhibited a weak androgenic effect.

  1. Neuraminidase inhibitory activities of quaternary isoquinoline alkaloids from Corydalis turtschaninovii rhizome.

    Science.gov (United States)

    Kim, Jang Hoon; Ryu, Young Bae; Lee, Woo Song; Kim, Young Ho

    2014-11-01

    Clostridium perfringens is a Gram-positive spore-forming bacterium that causes food poisoning. The neuraminidase (NA) protein of C. perfringens plays a pivotal role in bacterial proliferation and is considered a novel antibacterial drug target. Based on screens for novel NA inhibitors, a 95% EtOH extract of Corydalis turtschaninovii rhizome showed NA inhibitory activity (68% at 30 μg/ml), which resulted in the isolation of 10 isoquinoline alkaloids; namely, palmatine (1), berberine (2), coptisine (3), pseudodehydrocorydaline (4), jatrorrhizine (5), dehydrocorybulbine (6), pseudocoptisine (7), glaucine (8), corydaline (9) and tetrahydrocoptisine (10). Interestingly, seven quaternary isoquinoline alkaloids 1-7 (IC50 = 12.8 ± 1.5 to 65.2 ± 4.5 μM) showed stronger NA inhibitory activity than the tertiary alkaloids 8-10. In addition, highly active compounds 1 and 2 showed reversible non-competitive behavior based on a kinetic study. Molecular docking simulations using the Autodock 4.2 software increased our understanding of receptor-ligand binding of these compounds. In addition, we demonstrated that compounds 1 and 2 suppressed bacterial growth.

  2. Acetylcholinesterase inhibitory activity of Thai traditional nootropic remedy and its herbal ingredients.

    Science.gov (United States)

    Tappayuthpijarn, Pimolvan; Itharat, Arunporn; Makchuchit, Sunita

    2011-12-01

    The incidence of Alzheimer disease (AD) is increasing every year in accordance with the increasing of elderly population and could pose significant health problems in the future. The use of medicinal plants as an alternative prevention or even for a possible treatment of the AD is, therefore, becoming an interesting research issue. Acetylcholinesterase (AChE) inhibitors are well-known drugs commonly used in the treatment of AD. The aim of the present study was to screen for AChE inhibitory activity of the Thai traditional nootropic recipe and its herbal ingredients. The results showed that ethanolic extracts of four out of twenty-five herbs i.e. Stephania pierrei Diels. Kaempfera parviflora Wall. ex Baker, Stephania venosa (Blume) Spreng, Piper nigrum L at 0.1 mg/mL showed % AChE inhibition of 89, 64, 59, 50; the IC50 were 6, 21, 29, 30 microg/mL respectively. The other herbs as well as combination of the whole recipe had no synergistic inhibitory effect on AChE activity. However some plants revealed antioxidant activity. More research should have be performed on this local wisdom remedy to verify the uses in scientific term.

  3. Docking studies: In silico phosphodiesterase inhibitory activity of commercially available flavonoids

    Directory of Open Access Journals (Sweden)

    Arumugam Madeswaran

    2012-03-01

    Full Text Available The objective of the current study is to evaluate the phosphodiesterase inhibitory activity of flavonoids using in silico docking studies. In silico docking studies were carried out using AutoDock 4.2, based on the Lamarckian genetic algorithm principle. The results showed that all the selected flavonoids showed binding energy ranging between -7.50 kcal/mol to -6.61 kcal/mol when compared with that of the standard (-4.77 kcal/mol. Inhibition constant (3.17 µM to 14.36 µM and intermolecular energy (-9.29 kcal/mol to -8.70 kcal/mol of the ligands also coincide with the binding energy. All the selected flavonoids contributed better phosphodiesterase inhibitory activity because of its structural parameters. Benzopyran ring in the flavonoids are majorly contributed its activity. These molecular docking analyses could lead to the further development of potent phosphodiesterase inhibitors for the treatment of inflammatory diseases.

  4. Novel polyacetylene derivatives and their inhibitory activities on acetylcholinesterase obtained from Panax ginseng roots.

    Science.gov (United States)

    Murata, Kazuya; Iida, Daiki; Ueno, Yoshihiro; Samukawa, Keiichi; Ishizaka, Toshihiko; Kotake, Takeshi; Matsuda, Hideaki

    2017-01-01

    In our research program to identify cholinesterase and β-secretase inhibitors, we investigated Ginseng (root of Panax ginseng), a crude drug described as a multifunctional drug in the ancient Chinese herbal book Shennong Ben Cao Jing. Results from hexane and methanol extracts showed moderate inhibitory activities. This suggests that ginseng roots may be effective for the prevention of and therapy for dementia. We then focused on hexane extracts of raw ginseng root and dried ginseng root since the determination of hexane extract constituents has not been studied extensively. Activity-guided fractionation and purification led to the isolation of 4 polyacetylene compounds; homopanaxynol, homopanaxydol, (9Z)-heptadeca-1, 9-diene-4,6-diyn-3-one, and (8E)-octadeca-1,8-diene-4,6-diyn-3,10-diol. The chemical structures of these compounds, including stereochemistry, were determined. This is the first study to identify the structure of homopanaxynol and homopanaxydol. Moreover, the modes of action of some compounds were characterized as competitive inhibitors. This study showed, for the first time, that polyacetylene compounds possess acetylcholinesterase inhibitory activities.

  5. Effects of nanosuspension and inclusion complex techniques on the in vitro protease inhibitory activity of naproxen

    Energy Technology Data Exchange (ETDEWEB)

    Dharmalingam, Senthil Rajan; Chidambaram, Kumarappan; Srinivasan, Ramamurthy; Nadaraju, Shamala, E-mail: dsenthilrajan@yahoo.co.in [School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur (Malaysia)

    2014-01-15

    This study investigated the effects of nanosuspension and inclusion complex techniques on in vitro trypsin inhibitory activity of naproxen—a member of the propionic acid derivatives, which are a group of antipyretic, analgesic, and non-steroidal anti-inflammatory drugs. Nanosuspension and inclusion complex techniques were used to increase the solubility and anti-inflammatory efficacy of naproxen. The evaporative precipitation into aqueous solution (EPAS) technique and the kneading methods were used to prepare the nanosuspension and inclusion complex of naproxen, respectively. We also used an in vitro protease inhibitory assay to investigate the anti-inflammatory effect of modified naproxen formulations. Physiochemical properties of modified naproxen formulations were analyzed using UV, IR spectra, and solubility studies. Beta-cyclodextrin inclusion complex of naproxen was found to have a lower percentage of antitryptic activity than a pure nanosuspension of naproxen did. In conclusion, nanosuspension of naproxen has a greater anti-inflammatory effect than the other two tested formulations. This is because the nanosuspension formulation reduces the particle size of naproxen. Based on these results, the antitryptic activity of naproxen nanosuspension was noteworthy; therefore, this formulation can be used for the management of inflammatory disorders. (author)

  6. Inhibition of lipase and inflammatory mediators by Chlorella lipid extracts for antiacne treatment

    Directory of Open Access Journals (Sweden)

    G Sibi

    2015-01-01

    Full Text Available Acne vulgaris is a chronic inflammatory disease, and its treatment is challenging due to the multifactorial etiology and emergence of antibiotic-resistant Propionibacterium acnes strains. This study was focused to reduce antibiotics usage and find an alternate therapeutic source for treating acne. Lipid extracts of six Chlorella species were tested for inhibition of lipase, reactive oxygen species (ROS production, cytokine production using P. acnes (Microbial Type Culture Collection 1951. Lipase inhibitory assay was determined by dimercaprol Tributyrate - 5, 5′- dithiobis 2-nitrobenzoic acid method and ROS production assay was performed using nitro-blue tetrazolium test. The anti-inflammatory activity of algal lipid extracts was determined by in vitro screening method based on inhibition of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α produced by human peripheral blood mononuclear cells. Minimum inhibitory concentration (MIC values of lipid extracts were determined by microdilution method, and the fatty acid methyl esters (FAME were analyzed by gas chromatography-mass spectroscopy. Chlorella ellipsoidea has the highest lipase inhibitory activity with 61.73% inhibition, followed by Chlorella vulgaris (60.31% and Chlorella protothecoides (58.9%. Lipid extracts from C. protothecoides and C. ellipsoidea has significantly reduced the ROS production by 61.27% and 58.34% respectively. Inhibition of pro-inflammatory cytokines TNF-α showed the inhibition ranging from 58.39% to 78.67%. C. vulgaris has exhibited the MICvalue of 10 μg/ml followed by C. ellipsoidea, C. protothecoides and Chlorella pyrenoidosa (20 μg/ml. FAME analysis detected 19 fatty acids of which 5 were saturated fatty acids, and 14 were unsaturated fatty acids ranging from C14 to C24. The results suggest that lipid extracts of Chlorella species has significant inhibitory activity on P. acnes by inhibiting lipase activity. Further, anti-inflammatory reaction caused

  7. Natural inhibitors of pancreatic lipase as new players in obesity treatment.

    Science.gov (United States)

    de la Garza, Ana Laura; Milagro, Fermín I; Boque, Noemí; Campión, Javier; Martínez, J Alfredo

    2011-05-01

    Obesity is a multifactorial disease characterized by an excessive weight for height due to an enlarged fat deposition such as adipose tissue, which is attributed to a higher calorie intake than the energy expenditure. The key strategy to combat obesity is to prevent chronic positive impairments in the energy equation. However, it is often difficult to maintain energy balance, because many available foods are high-energy yielding, which is usually accompanied by low levels of physical activity. The pharmaceutical industry has invested many efforts in producing antiobesity drugs; but only a lipid digestion inhibitor obtained from an actinobacterium is currently approved and authorized in Europe for obesity treatment. This compound inhibits the activity of pancreatic lipase, which is one of the enzymes involved in fat digestion. In a similar way, hundreds of extracts are currently being isolated from plants, fungi, algae, or bacteria and screened for their potential inhibition of pancreatic lipase activity. Among them, extracts isolated from common foodstuffs such as tea, soybean, ginseng, yerba mate, peanut, apple, or grapevine have been reported. Some of them are polyphenols and saponins with an inhibitory effect on pancreatic lipase activity, which could be applied in the management of the obesity epidemic.

  8. Enzyme Inhibitory Properties, Antioxidant Activities, and Phytochemical Profile of Three Medicinal Plants from Turkey

    Directory of Open Access Journals (Sweden)

    Gokhan Zengin

    2015-01-01

    Full Text Available We aimed to investigate the inhibitory potential of three medicinal plants (Hedysarum varium, Onobrychis hypargyrea, and Vicia truncatula from Turkey against key enzymes involved in human pathologies, namely, diabetes (α-amylase and α-glucosidase, neurodegenerative disorders (tyrosinase, acetylcholinesterase, and butyrylcholinesterase, and hyperpigmentation (tyrosinase. The antioxidant potential, phenolic and flavonoid content of ethyl acetate, and methanolic and aqueous extracts were investigated using in vitro assays. The total antioxidant capacity (TAC, β-carotene/linoleic acid bleaching activity, 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH•, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+, cupric ion reducing antioxidant capacity (CUPRAC, ferric reducing antioxidant power (FRAP, and metal chelating activity on ferrous ions were used to evaluate the antioxidant capabilities of the extracts. The half-maximal inhibitory concentrations (IC50 of the extracts on cholinesterase, tyrosinase, and α-amylase were significantly higher than the references, galantamine, kojic acid, and acarbose, respectively. The half-maximal effective concentrations (EC50 of the extracts on TAC, CUPRAC, and FRAP were significantly higher than trolox. The phenol and flavonoid contents of the plant extracts were in the range 20.90±0.190–83.25±0.914 mg gallic acid equivalent/g extract and 1.45±0.200–39.71±0.092 mg rutin equivalent/g extract, respectively. The plants were found to possess moderate antioxidant capacities and interesting inhibitory action against key enzymes.

  9. Study the effect of F17S mutation on the chimeric Bacillus thermocatenulatus lipase

    Directory of Open Access Journals (Sweden)

    Seyed Hossein Khaleghinejad

    2016-06-01

    Full Text Available Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3 are one of the highest value commercial enzymes as they have potential applications in biotechnology for detergents, food, pharmaceuticals, leather, textiles, cosmetics, and paper industries; and are currently receiving considerable attention because of their potential applications in biotechnology. Bacillus thermocatenulatus Lipase 2 (BTL2 is one of the most important research targets, because of its potential industrial applications. In this study, the effect of substitution Phe17 with Ser in mutated BTL2 lipase, which conserved pentapeptide (112Ala-His-Ser-Gln-Gly116 was replaced with similar sequences (207Gly-Glu-Ser-Ala-Gly211 of Candida rugosa lipase (CLR at the nucleophilic elbow region. Docking results confirmed the mutated lipase to be better than the chimeric lipase. So, cloning was conducted, and the mutated and chimeric btl2 genes were expressed in Escherichia coli, and then the enzymes were purified by anion exchange chromatography. The mutation increased lipase lipolytic activity against most of the applied substrates, with the exception of tributyrin when compared with chimeric lipase. Further, the mutated lipase exhibited higher activity than the chimeric lipase at all temperatures. Optimum pH of the mutated lipase was obtained at pH 9.5, which was more than the chimeric one. Enzyme activity of the mutated lipase in the presence of organic solvents, detergents, and metal ions was also improved than the chimeric lipase.

  10. NEW LIPASE-PRODUCERS MICROORGANISMS FROM PERUVIAN AMAZONIA WHICH HYDROLYZE PALM OIL AND DERIVATIVES

    OpenAIRE

    Roxana Trujillo; Pedro Peláez; Josep-Vicent Sinisterra

    2014-01-01

    Two yeasts: Cryptococcus uchicensis TMY9 and Pichia uchicensis TMY10 and one fungus Verticillium tingalensis TMFMB are described for the first time as lipase producer microorganisms. The strains have been isolated after an ecological screening in a palm oil industry. The yeasts- C. uchicensis and Pichia uchicensis - mainly produce extracellular lipases as active as those produced by traditional lipase producing microorganisms. The extracellular lipases are active in the hydrolysis of crude pa...

  11. Expression and inhibitory activity analysis of a 25-kD Bowman-Birk protease inhibitor in rice

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Rice Bowman-Birk inhibitors (RBBI), with one (8 kD) or two homologous domains (16 kD), were found to be effective trypsin inhibitors in vitro. In this study, we demonstrate that the 25-kD protein corresponding to the three-domain RBBI indeed exists in rice in planta, and that the RBBIs are regulated by development and wounding. We also found by inhibitory activity assay that the 3:13 disulfide bond, but not the 4:5 disulfide bond, suppresses the trypsin-inhibitory activity, and the D3 domain of RBBI3-1 has no inhibitory activity against trypsin, chymotrypsin, paparin or subtilisin. Mutation analyses showed that conversion from Lys to Leu or Tyr in the N-terminal P1 site in D1 domain did not create chymotrypsin-inhibitory activity, suggesting that the structure of the reactive loop in D1 domain hinder the new inhibitory specificity at P1 site, and the chymotrypsin-inhibitory activity might need the participation of other structures, e.g. 3:13 disulfide bond.

  12. Inhibitory effect of aqueous dandelion extract on HIV-1 replication and reverse transcriptase activity

    Directory of Open Access Journals (Sweden)

    Han Huamin

    2011-11-01

    Full Text Available Abstract Background Acquired immunodeficiency syndrome (AIDS, which is caused by the human immunodeficiency virus (HIV, is an immunosuppressive disease that results in life-threatening opportunistic infections. The general problems in current therapy include the constant emergence of drug-resistant HIV strains, adverse side effects and the unavailability of treatments in developing countries. Natural products from herbs with the abilities to inhibit HIV-1 life cycle at different stages, have served as excellent sources of new anti-HIV-1 drugs. In this study, we aimed to investigate the anti-HIV-1 activity of aqueous dandelion extract. Methods The pseudotyped HIV-1 virus has been utilized to explore the anti-HIV-1 activity of dandelion, the level of HIV-1 replication was assessed by the percentage of GFP-positive cells. The inhibitory effect of the dandelion extract on reverse transcriptase activity was assessed by the reverse transcriptase assay kit. Results Compared to control values obtained from cells infected without treatment, the level of HIV-1 replication and reverse transcriptase activity were decreased in a dose-dependent manner. The data suggest that dandelion extract has a potent inhibitory activity against HIV-1 replication and reverse transcriptase activity. The identification of HIV-1 antiviral compounds from Taraxacum officinale should be pursued. Conclusions The dandelion extract showed strong activity against HIV-1 RT and inhibited both the HIV-1 vector and the hybrid-MoMuLV/MoMuSV retrovirus replication. These findings provide additional support for the potential therapeutic efficacy of Taraxacum officinale. Extracts from this plant may be regarded as another starting point for the development of an antiretroviral therapy with fewer side effects.

  13. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  14. Immobilised lipase for in vitro lipolysis experiments.

    Science.gov (United States)

    Phan, Stephanie; Salentinig, Stefan; Hawley, Adrian; Boyd, Ben J

    2015-04-01

    In vitro lipolysis experiments are used to assess digestion of lipid-based formulations, and probe solubilisation by colloidal phases during digestion. However, proteins and other biological components in the pancreatin often used as the lipase result in high-background scattering when interrogating structures using scattering approaches, complicating the resolution of colloidal structures. In this study, to circumvent this problem, a modified in vitro digestion model employing lipase immobilised on polymer beads, which allows for separation of the lipid digestion components during lipolysis, was investigated. Titration of the fatty acids released during digestion of medium chain triglycerides using pancreatin compared with immobilised lipase, combined with HPLC was used to follow the digestion, and small-angle X-ray scattering was used to determine colloidal struct