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Sample records for solubilized benzoyl peroxide

  1. Rapid detection of benzoyl peroxide in wheat flour by using Raman scattering spectroscopy

    Science.gov (United States)

    Zhao, Juan; Peng, Yankun; Chao, Kuanglin; Qin, Jianwei; Dhakal, Sagar; Xu, Tianfeng

    2015-05-01

    Benzoyl peroxide is a common flour additive that improves the whiteness of flour and the storage properties of flour products. However, benzoyl peroxide adversely affects the nutritional content of flour, and excess consumption causes nausea, dizziness, other poisoning, and serious liver damage. This study was focus on detection of the benzoyl peroxide added in wheat flour. A Raman scattering spectroscopy system was used to acquire spectral signal from sample data and identify benzoyl peroxide based on Raman spectral peak position. The optical devices consisted of Raman spectrometer and CCD camera, 785 nm laser module, optical fiber, prober, and a translation stage to develop a real-time, nondestructive detection system. Pure flour, pure benzoyl peroxide and different concentrations of benzoyl peroxide mixed with flour were prepared as three sets samples to measure the Raman spectrum. These samples were placed in the same type of petri dish to maintain a fixed distance between the Raman CCD and petri dish during spectral collection. The mixed samples were worked by pretreatment of homogenization and collected multiple sets of data of each mixture. The exposure time of this experiment was set at 0.5s. The Savitzky Golay (S-G) algorithm and polynomial curve-fitting method was applied to remove the fluorescence background from the Raman spectrum. The Raman spectral peaks at 619 cm-1, 848 cm-1, 890 cm-1, 1001 cm-1, 1234 cm-1, 1603cm-1, 1777cm-1 were identified as the Raman fingerprint of benzoyl peroxide. Based on the relationship between the Raman intensity of the most prominent peak at around 1001 cm-1 and log values of benzoyl peroxide concentrations, the chemical concentration prediction model was developed. This research demonstrated that Raman detection system could effectively and rapidly identify benzoyl peroxide adulteration in wheat flour. The experimental result is promising and the system with further modification can be applicable for more products in near

  2. Investigation of the decomposition reaction and dust explosion characteristics of crystalline benzoyl peroxides

    International Nuclear Information System (INIS)

    Lu, K.-T.; Chen, T.-C.; Hu, K.-H.

    2009-01-01

    The benzoyl peroxide (BPO) is widely used in the chemical industry. Many catastrophes have been caused by its thermal instability or reactive incompatibility in storage or thermal decomposition reaction. Thus, its hazard characteristics have to be clearly identified. First of all, the differential scanning calorimeter (DSC) is used to measure the heat of decomposition reaction, which can contribute to understanding the reaction characteristics of benzoyl peroxide. The accelerating rate calorimeter (ARC) is used to measure the rates of temperature and pressure rises of decomposition reaction, and then the kinetics parameters are estimated. Furthermore, the MIKE 3 apparatus and the 20-l-Apparatus are used to measure and analyze the dust explosion characteristics of benzoyl peroxide under room temperature and atmospheric pressure. Finally, Semenov's thermal explosion theory is applied to investigate the critical runaway condition and the stability criterion of decomposition reaction, and to build the relationship of critical temperature, convective heat transfer coefficient, heat transfer surface area and ambient temperature. These results contribute to improving the safety in the reaction, transportation and storage processes of benzoyl peroxide

  3. Profile of clindamycin phosphate 1.2%/benzoyl peroxide 3.75% aqueous gel for the treatment of acne vulgaris

    Science.gov (United States)

    Nguyen, Tuyet A; Eichenfield, Lawrence F

    2015-01-01

    Acne vulgaris is a common and chronic skin disease, and is a frequent source of morbidity for affected patients. Treatment of acne vulgaris is often difficult due to the multifactorial nature of this disease. Combination therapy, such as that containing clindamycin and benzoyl peroxide, has become the standard of care. Several fixed formulations of clindamycin 1% and benzoyl peroxide of varying concentrations are available and have been used with considerable success. The major limitation is irritation and dryness from higher concentrations of benzoyl peroxide, and a combination providing optimal efficacy and tolerability has yet to be determined. Recently, a clindamycin and benzoyl peroxide 3.75% fixed combination formulation was developed. Studies have suggested that this formulation may be a safe and effective treatment regimen for patients with acne vulgaris. Here, we provide a brief review of acne pathogenesis, benzoyl peroxide and clindamycin, and profile a new Clindamycin-BP 3.75% fixed combination gel for the treatment of moderate-to-severe acne vulgaris. PMID:26604811

  4. Sensory and Functionality Differences of Whey Protein Isolate Bleached by Hydrogen or Benzoyl Peroxide.

    Science.gov (United States)

    Smith, Tucker J; Foegeding, E Allen; Drake, MaryAnne

    2015-10-01

    Whey protein is a highly functional food ingredient used in a wide variety of applications. A large portion of fluid whey produced in the United States is derived from Cheddar cheese manufacture and contains annatto (norbixin), and therefore must be bleached. The objective of this study was to compare sensory and functionality differences between whey protein isolate (WPI) bleached by benzoyl peroxide (BP) or hydrogen peroxide (HP). HP and BP bleached WPI and unbleached controls were manufactured in triplicate. Descriptive sensory analysis and gas chromatography-mass spectrometry were conducted to determine flavor differences between treatments. Functionality differences were evaluated by measurement of foam stability, protein solubility, SDS-PAGE, and effect of NaCl concentration on gelation relative to an unbleached control. HP bleached WPI had higher concentrations of lipid oxidation and sulfur containing volatile compounds than both BP and unbleached WPI (P protein loss at pH 4.6 of WPI decreased by bleaching with either hydrogen peroxide or benzoyl peroxide (P whey with either BP or HP resulted in protein degradation, which likely contributed to functionality differences. These results demonstrate that bleaching has flavor effects as well as effects on many of the functionality characteristics of whey proteins. Whey protein isolate (WPI) is often used for its functional properties, but the effect of oxidative bleaching chemicals on the functional properties of WPI is not known. This study identifies the effects of hydrogen peroxide and benzoyl peroxide on functional and flavor characteristics of WPI bleached by hydrogen and benzoyl peroxide and provides insights for the product applications which may benefit from bleaching. © 2015 Institute of Food Technologists®

  5. Allergic Contact Dermatitis to Benzoyl Peroxide Resembling Impetigo.

    Science.gov (United States)

    Kim, Changhyun; Craiglow, Brittany G; Watsky, Kalman L; Antaya, Richard J

    2015-01-01

    A 17-year-old boy presented with recurring severe dermatitis of the face of 5-months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris. © 2015 Wiley Periodicals, Inc.

  6. Formulation and Characterization of Benzoyl Peroxide Gellified Emulsions

    Science.gov (United States)

    Thakur, Naresh Kumar; Bharti, Pratibha; Mahant, Sheefali; Rao, Rekha

    2012-01-01

    The present investigation was carried out with the objective of formulating a gellified emulsion of benzoyl peroxide, an anti-acne agent. The formulations were prepared using four different vegetable oils, viz. almond oil, jojoba oil, sesame oil, and wheat germ oil, owing to their emollient properties. The idea was to overcome the skin irritation and dryness caused by benzoyl peroxide, making the formulation more tolerable. The gellified emulsions were characterized for their homogeneity, rheology, spreadability, drug content, and stability. In vitro permeation studies were performed to check the drug permeation through rat skin. The formulations were evaluated for their antimicrobial activity, as well as their acute skin irritation potential. The results were compared with those obtained for the marketed formulation. Later, the histopathological examination of the skin treated with various formulations was carried out. Formulation F3 was found to have caused a very mild dysplastic change to the epidermis. On the other hand, the marketed formulation led to the greatest dysplastic change. Hence, it was concluded that formulation F3, containing sesame oil (6%w/w), was the optimized formulation. It exhibited the maximum drug release and anti-microbial activity, in addition to the least skin irritation potential. PMID:23264949

  7. Remediation of Contaminated Soils by Thermal Desorption; Effect of Benzoyl Peroxide Addition.

    Czech Academy of Sciences Publication Activity Database

    Kaštánek, František; Topka, Pavel; Soukup, Karel; Maléterová, Ywetta; Demnerová, K.; Kaštánek, Petr; Šolcová, Olga

    2016-01-01

    Roč. 125, JUL 1 (2016), s. 309-313 ISSN 0959-6526 R&D Projects: GA TA ČR TA04020700 Institutional support: RVO:67985858 Keywords : soil * hydrocarbons * benzoyl peroxide Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.715, year: 2016

  8. Randomized, Observer-blind, Split-face Compatibility Study with Clindamycin Phosphate 1.2%/Benzoyl Peroxide 3.75% gel and Facial Foundation Makeup.

    Science.gov (United States)

    Bhatia, Neal; Pillai, Radhakrishnan

    2015-09-01

    Cosmetic compatibility in the treatment of acne is an important issue significantly impacting quality of life, but often overlooked, as dermatologists commonly recommended avoidance of cosmetic foundations when treating adult female patients. Fixed combinations of clindamycin/benzoyl peroxide are widely used in the treatment of acne, but little is known about the impact of their concomitant use with facial foundation. To assess the compatibility of clindamycin phosphate 1. 2%/benzoyl peroxide 3. 75% gel with foundation makeup for up to six hours after application. Twenty-nine female subjects applied makeup to their face after randomly applying clindamycin phosphate 1. 2%/benzoyl peroxide 3. 75% gel to one side of the face. Investigator and subject self- assessment included facial skin attributes, facial tolerability, and cosmetic compatibility post-application and at Hour 6; as well as cutaneous tolerability. No statistical difference was noted between the treated and untreated side of the face in terms of coverage, blotchiness, appearance, skin tone, or visual smoothness. Tolerability was excellent, with no erythema, edema, dryness, and peeling post-makeup application. For both the treated and untreated side, there was a slight lack of improvement in cosmetic appearance six hours post-makeup application. Clindamycin/benzoyl peroxide 3. 75% gel was shown to have excellent cosmetic compatibility with facial foundation.

  9. Simple and fast fluorescence detection of benzoyl peroxide in wheat flour by N-methoxy rhodamine-6G spirolactam based on consecutive chemical reactions

    International Nuclear Information System (INIS)

    Chen Wei; Shi Wen; Li Zhao; Ma Huimin; Liu Yang; Zhang Jinghua; Liu Qingjun

    2011-01-01

    Graphical abstract: A simple and fast method for fluorescence detection of benzoyl peroxide in wheat flour by N-methoxy rhodamine-6G spirolactam (1) is proposed based on consecutive chemical reactions. Highlights: ► Benzoyl peroxide can oxidize Fe 2+ into Fe 3+ . ► Fe 3+ selectively induces the opening of rhodamine spirolactam ring. ► The two reactions led to the development of a new fluorescent method for benzoyl peroxide. ► The method is simple and fast, and is used to detect benzoyl peroxide in wheat flour. - Abstract: Benzoyl peroxide (BPO) as a brightener is often added to wheat flour, and excessive use of this food additive is receiving increasing concern. Herein, a simple and fast method for fluorescence detection of BPO is proposed based on consecutive chemical reactions. In this approach, BPO first oxidizes Fe 2+ into Fe 3+ and the resulting Fe 3+ then induces the opening of the spirolactam ring of a new rhodamine derivative, N-methoxy rhodamine-6G spirolactam, switching on fluorescence of the detection system. More importantly, the fluorescence response of the reaction system to BPO is rather rapid and sensitive, with a detection limit of 6 mg kg −1 (k = 3), which makes it to be of great potential use in food safety analysis. The applicability of the proposed method has been successfully demonstrated on the determination of BPO in wheat flour samples.

  10. Comparative evaluation of retinoic acid, benzoyl peroxide and erythromycin lotion in acne vulgarils

    Directory of Open Access Journals (Sweden)

    Dogra A

    1993-01-01

    Full Text Available Ninety three patients suffering from acne vulgaris were treated with 0.05% retinoic acid (23 patients, 10% benzyoyl peroxide (24 patients, 2% erythromycin lotin (25 patients and 50% glycerine in methylated spirit (21 patients used as a control, for a period of 6 weeks. The patients were evaluated at 2 weeks and 6 weeks by spot counting of the lesions and diagrammatic representations. Good to excellent results were obtained in 69.6% of patients of erythromycin lotion. Retinoic acid was more effective in reducing noninflammatory lesions (75.2% whereas inflammatory lesions showed better response (73.6% with erythromycin lotion and benzoyl peroxide was almost equally effective in both types of lesions.

  11. Sub-group Analyses from a Trial of a Fixed Combination of Clindamycin Phosphate 1.2% and Benzoyl Peroxide 3.75% Gel for the Treatment of Moderate-to-severe Acne Vulgaris

    Science.gov (United States)

    Korotzer, Andrew

    2015-01-01

    Background: Acne vulgaris is commonplace and can be difficult to manage. Providing an effective and well-tolerated treatment may lead to improved adherence, increased patient satisfaction, and improved clinical outcomes. Methods: A review of efficacy, safety, and cutaneous tolerability of clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel in 498 patients with moderate-to-severe acne vulgaris enrolled in a multicenter Phase III study randomized to receive active or vehicle once daily for 12 weeks, including the most recent post-hoc analyses. Results: Significantly superior reductions in lesion counts were observed with clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel from Week 4, with median percent reductions in inflammatory and noninflammatory lesions from baseline of 68.4 and 57.9 percent, respectively (bothpacne vulgaris patients treated with clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel achieved ≥2-grade improvement from baseline in their Evaluator’s Global Severity Score, and almost a third of the adolescent acne vulgaris patients (32.4%) achieved at least a marked improvement in their acne vulgaris as early as Week 2. In adult female acne overall treatments success was achieved in 52.7 percent of patients treated with clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel. Overall, and in the specific subpopulations, clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel was well-tolerated with a similar adverse event profile to vehicle. Limitations: Post-hoc analyses from a single clinical trial with demographic imbalances that could potentially confound the results. Conclusion: Clindamycin phosphate 1.2%-benzoyl peroxide 3.75% gel appears to be effective in treating acne across various clinically relevant sub-groups. PMID:26705445

  12. Comparison of the efficacy and safety of topical clindamycin and 5% benzoyl peroxide with nadifloxacin cream and 5% benzoyl peroxide gel in the treatment of acne vulgaris and assessment of the effects of these treatments on quality of life

    Directory of Open Access Journals (Sweden)

    Aslıhan Kırkağaç

    2015-03-01

    Full Text Available Background and Design: Acne vulgaris is a multifactorial chronic inflammatory disase of the pilosebaceous unit. Topical antibiotics and anti-inflammatory treatment are used for mild and moderate acne. Clindamycin is frequently used for acne treatment, altough nadifloxacin is a relatively new agent. There are few studies evaluating nadifloxacin efficacy. It's impact on quality of life has not been determined previously. In this study, it is aimed to compare the effect of these two agents, and to evaluate the effect of these treatments on quality of life. Materials and Methods: Eighty patients with mild-moderate acne vulgaris were divided in two groups of 40 people that had no difference in terms of age, gender and acne severity. The combination of topical clindamycin and 5% benzoyl peroxide gel twice a day was given to group 1 for 12 weeks. The combination of nadifloxacin cream and 5% benzoyl peroxide gel twice a day was given to group 2 for 12 weeks. The number of the inflammatory and non-inflammatory lesions were recorded at baseline and on weeks 2, 4, 8, 12 and side effects were recorded and evaluated. Global improvement was evaluated separately by patients and doctor after the treatment. Before and after the treatment, the quality of life of the patients were evaluated with Skindex-29. Results: Both treatment group regimens were significantly effective on inflammatory and non-inflammatory lesions and were well tolerated by patients in terms of side effects. It was also observed that there was statistically significant recovery after treatment in terms of clinical severity and quality of life. There was not any statistically significant difference between two treatment methods in terms of effectiveness, side effect and quality of life. Conclusion: Nadifloxacin and 5% benzoyl peroxide combination is effective in the treatment and improvement of quality of life in acne patients.

  13. Comparison of a chlorhexidine and a benzoyl peroxide shampoo as sole treatment in canine superficial pyoderma.

    Science.gov (United States)

    Loeffler, A; Cobb, M A; Bond, R

    2011-09-03

    The clinical and antibacterial efficacy of two shampoos used as a sole antibacterial treatment in dogs with superficial pyoderma were investigated and compared. In a randomised, partially blinded study, a 3 per cent chlorhexidine gluconate shampoo (Chlorhex 3; Leo Animal Health) was compared against a 2.5 per cent benzoyl peroxide shampoo (Paxcutol; Virbac) in 22 dogs with superficial pyoderma. Dogs were washed two to three times weekly with a 10-minute contact time over 21 days. Clinical scores and bacterial counts were assessed on days 1, 8 and 22 and compared within and between treatment groups; overall response was assessed at the end of the study. Twenty dogs completed the study; 15 (68.2 per cent) showed an overall clinical improvement and the clinical signs resolved in three chlorhexidine-treated dogs. In the chlorhexidine-treated group, scores for papules/pustules (P<0.001), investigator-assessed pruritus (P=0.003), total bacterial counts (P=0.003) and counts for coagulase-positive staphylococci (P=0.003) were reduced after three weeks. Scores and bacterial counts did not vary significantly in the benzoyl peroxide-treated group.

  14. A randomized, double-blind, multicenter, parallel group study to compare relative efficacies of the topical gels 3% erythromycin/5% benzoyl peroxide and 0.025% tretinoin/erythromycin 4% in the treatment of moderate acne vulgaris of the face.

    Science.gov (United States)

    Gupta, Aditya K; Lynde, Charles W; Kunynetz, Rod A W; Amin, Smita; Choi, Ken; Goldstein, Eric

    2003-01-01

    Combination treatments for acne vulgaris, such as Benzamycin (3% erythromycin/5% benzoyl peroxide) and Stievamycin (0.025% tretinoin/erythromycin 4%), reduce bacterial growth, which contributes to the inflammatory lesions typical of adolescent acne, and also decrease the epidermal cell compaction which may form the characteristic noninflammatory comedone. Both agents contain erythromycin to reduce the growth of Propionibacterium acnes in skin. Benzoyl peroxide has antibiotic activity as well as anticomedogenic properties. Tretinoin may increase the turnover of epidermal cells and loosen the cells compacted to form comedones. A combination preparation containing the two antibiotics may reduce the development of resistance; the combination preparation containing tretinoin and erythromycin will have an antibiotic effect as well as acting on differentiation. This multicenter, randomized, double-blind, parallel group study compared the effectiveness of 3% erythromycin/5% benzoyl peroxide and 0.025% tretinoin/erythromycin 4%, each applied twice daily in patients with moderate acne vulgaris. Overall physician and patient ratings of severity of acne symptoms were performed at baseline and at weeks 2, 4, 8, and 12. At baseline the two treatment groups had similar disease severity. The number of papules, pustules, and comedones was reduced in both treatment groups at week 12, and the reductions were not significantly different between the two comparators. Global physician rating of improvement was significantly higher in the 3% erythromycin/5% benzoyl peroxide group compared with the 0.025% tretinoin/erythromycin 4% group; however, there was no significant difference in global patient ratings between the two treatment groups. An aggregate score was produced, for both physician rating and patient rating, by adding up individual symptom severity ratings. Compared with 0.025% tretinoin/erythromycin 4%, 3% erythromycin/5% benzoyl peroxide provided significantly greater reduction

  15. Dapsone gel 5% in combination with adapalene gel 0.1%, benzoyl peroxide gel 4% or moisturizer for the treatment of acne vulgaris: a 12-week, randomized, double-blind study.

    Science.gov (United States)

    Fleischer, Alan B; Shalita, Alan; Eichenfield, Lawrence F; Abramovits, William; Lucky, Anne; Garrett, Steven

    2010-01-01

    To evaluate the safety and efficacy of dapsone gel 5% in the treatment of acne when used in combination with adapalene gel 0.1%, benzoyl peroxide gel 4% or moisturizer. This was a twelve-week, randomized, double-blind study. Patients aged 12 years and older (n=301) applied dapsone gel twice daily and were randomly assigned (1:1:1) to one of three additional treatments, applied once daily. By week 12, dapsone gel combined with any of the three additional treatments reduced the mean number of inflammatory lesions. However, the authors did not detect a significant difference in the reduction of inflammatory lesions when dapsone was used in combination with adapalene gel or with benzoyl peroxide gel compared to the dapsone plus moisturizer combination group (P=0.052 for both versus moisturizer combination). Patients treated with dapsone gel combined with adapalene showed a significantly better response in reduction in non-inflammatory and total acne lesion count than those who received the moisturizer combination. Local adverse reactions in all three treatment groups were minimal and generally mild in severity. Dapsone gel in combination with adapalene gel or benzoyl peroxide gel is safe and well tolerated for the treatment of acne vulgaris.

  16. Mechanisms of DNA damage by the tumor promoter and progressor benzoyl peroxide

    International Nuclear Information System (INIS)

    Swauger, J.E.; Dolan, P.M.; Zweier, J.L.; Kensler, T.W.

    1990-01-01

    Benzoyl peroxide (BzPO), a tumor promoter and progressor in mouse skin, produces strand breaks in DNA of exposed cells. Previously we have reported that the metabolism of BzPO in keratinocytes proceeds via the initial cleavage of the peroxide bond, yielding benzoyloxyl radicals which, in turn, can fragment to form phenyl radicals and carbon dioxide. Benzoic acid, the product of hydrogen abstraction by the benzoyloxyl radical, is the major stable metabolite of BzPO produced by keratinocytes. In the present study we have examined the capacity of BzPO to generate strand scissions in φX-174 plasmid DNA. DNA damage was dose-dependent over a concentration range of 10-1000 μM BzPO and was dependent on the presence of copper but not other transition state metals. By contrast, benzoic acid did not produce DNA damage in this system. The inclusion of spin trapping agents (PBN, DBNBS), radical scavenging agents (Nal, GSH), or the copper chelator o-phenanthroline in incubations was found to significantly reduce the extent of DNA damage. Electron paramagnetic resonance spectroscopy studies suggested that the primary radical trapped was the benzoyloxyl radical, implying a role for this radical in the generation of the observed DNA damage. Collectively these observations suggest BzPO may be activated to DNA damaging intermediates in keratinocytes via metal-catalyzed cleavage of the peroxide bond resulting in the formation of the benzoyloxyl radical. Covalent modification of DNA was not observed when [ 14 C]BzPO was incubated with calf thymus DNA in the presence of copper. Overall, these results suggest that BzPO induces DNA damage via benzoyloxyl radical mediated proton abstraction from the DNA strand and the adduct formation with DNA is unlikely to occur

  17. Efficacy of Intense-pulsed Light Therapy with Topical Benzoyl Peroxide 5% versus Benzoyl Peroxide 5% Alone in Mild-to-moderate Acne Vulgaris: A Randomized Controlled Trial.

    Science.gov (United States)

    Mokhtari, Fatemeh; Gholami, Maryam; Siadat, Amir Hossein; Jafari-Koshki, Tohid; Faghihi, Gita; Nilforoushzadeh, Mohammad Ali; Hosseini, Sayed Mohsen; Abtahi-Naeini, Bahareh

    2017-01-01

    Acne vulgaris is a disease of pilosebaceous unit with multifactorial pathogenesis and threats patients' social functioning. There is a growing research to find faster, more effective, and easy to use treatments. The aim of this study is to evaluate the efficacy of benzoyl peroxide 5% (BP) with and without concomitant intense-pulsed light (IPL) therapy in mild-to-moderate acne vulgaris. In this controlled trial, 58 eligible patients with mild-to-moderate acne and Fitzpatrick skin phototype III and IV were randomly allocated to two groups. All patients were asked to use a thin layer of BP every night. The IPL therapy was administered at the end of first, 2 nd , and 3 rd months. Acne Global Severity Scale (AGSS), Acne Severity Index (ASI), and total lesion counting (TLC) along with patient satisfaction were recorded. Patients were also examined 1 month after the final therapeutic visit. The IPL group showed greater reduction in AGSS ( P < 0.001) and TLC ( P = 0.005) than the control group. However, the difference in ASI was not significant ( P = 0.12). Patients in IPL groups were more satisfied than control group ( P < 0.001). Adding IPL to BP can result better response to BP alone. In acne treatment, combination therapy such as IPL and other topical agents should be kept in mind.

  18. The clinical impact of vehicle technology using a patented formulation of benzoyl peroxide 5%/clindamycin 1% gel: comparative assessments of skin tolerability and evaluation of combination use with a topical retinoid.

    Science.gov (United States)

    Del Rosso, James Q; Tanghetti, Emil

    2006-02-01

    A major challenge encountered in clinical practice in patients with acne vulgaris is irritation related to topical medications used for treatment. Advances in vehicle technology have improved formulations containing active ingredients known to produce irritation in some patients, such as benzoyl peroxide (BP) and topical retinoids. Clinical studies, including combination therapy studies have demonstrated that certain additives, such as silicates and specific humectants, reduce irritation by maintaining barrier integrity. A patented gel formulation of BP 5%/clindamycin phosphate 1% (clindamycin) containing dimethicone and glycerin has been studied both as a monotherapy and in combination with topical retinoid use. This article evaluates specific vehicle additives included in this gel formulation and explains their role in reducing irritation. Data from clinical trials utilizing this technology in acne management are also reviewed.

  19. STUDIES ON RADICAL POLYMERIZATION OF METHYL METHACRYLATE INITIATED WITH ORGANIC PEROXIDE-AMINE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; SHUI Li; FENG Xinde

    1984-01-01

    Radical polymerization of methyl methacrylate (MMA) initiated with various diacyl peroxideamine systems was studied. Benzoyl peroxide (BPO) and lauroyl peroxide (LPO) were used as diacyl peroxide component, N,N-dimethyl aniline (DMA) and its para substituted derivatives, i.e., N,N-dimethyl-p-toluidine (DMT), p-hydroxymethyl-N,N-dimethyl aniline (HDMA), p-nitro-N,N-dimethyl aniline (NDMA) and p-dimethylamino benzaldehyde (DMAB) were used as amine components. It was found that the peroxide-DMT systems give higher rates of bulk polymerization Rp of MMA than the organic hydroperoxide-DMT systems with the following descending order BPO-DMT>LPO-DMT>CHP (cumene hydroperoxide)-DMT>TBH (tert-butyl hydroperoxide)-DMT.The aromatic tertiary amines possess obvious structural effect on the Rp values in the diacyl peroxideamine system. The overall activation energy of MMA polymerization was determined and the kinetics of polymerization of MMA initiated with BPO-DMT system was investigated.

  20. Determination of active oxygen content in rare earth peroxides

    International Nuclear Information System (INIS)

    Queiroz, Carlos A.S.; Abrao, Alcidio

    1993-01-01

    The content of active oxygen in rare earth peroxides have been determined after the dissolution of the samples with hydrocloridic acid in the presence of potassium iodide. The free generated iodine is titrated with sodium thiosulfate using starch as indicator. The oxidation of iodide to the free iodine indicates the presence of a higher valence state rare earth oxide, until now specifically recognized for the oxides of cerium (Ce O 2 ), praseodymium (Pr 6 O 1 1) and terbium (TB 4 O 7 ). recently the authors synthesized a new series of rare earth compounds, the peroxides. These new compounds were prepared by precipitating the rare earth elements complexed with carbonate ion by addition of hydrogen peroxide. the authors demonstrated that all rare earth elements, once solubilized by complexing with carbonate ion, are quantitatively precipitated as peroxide by addition of hydrogen peroxide. (author)

  1. Systemic exposure to benzoic acid and hippuric acid following topical application of clindamycin 1%/benzoyl peroxide 3% fixed-dose combination gel in Japanese patients with acne vulgaris.

    Science.gov (United States)

    Ino, Hiroko; Takahashi, Naoki; Saenz, Alessandra Alio; Wakamatsu, Akira; Hashimoto, Hirofumi; Nakahara, Norie; Hasegawa, Setsuo

    2015-01-01

    Clindamycin 1%/benzoyl peroxide 3% fixed-dose combination gel (CLDM/BPO3%) is a topical product for the treatment of acne vulgaris. In this study, plasma and urine concentrations of benzoic acid (BA) and hippuric acid (HA) were analyzed to estimate the pharmacokinetics (PK) of BPO after application of CLDM/BPO3% twice-daily for 7 days in Japanese patients with acne vulgaris. Seven-day repeated application of CLDM/BPO3% appears to be safe in this patient population. Concentrations of plasma and urine BA were below the limit of quantification before and after repeated application in most of the 12 adult male patients. Mean difference in Cmax and AUC0-last for plasma HA indicated increased exposures after repeated application, but with wide 90% confidence intervals. Mean Ae0-12 for urine HA was similar before and after repeated application. Repeated application of CLDM/BPO3% is thus unlikely to result in accumulation of BA and HA. The study suggests negligible systemic exposure to BPO metabolites from CLDM/BPO3% after 7-day repeated application in male patients with acne vulgaris. © 2014, The American College of Clinical Pharmacology.

  2. SHORT COMMUNICATION CHEMOSELECTIVE C-BENZOYLATION ...

    African Journals Online (AJOL)

    BCSE

    Department of Chemistry, Savitribaiphule Pune University, Pune 411007, India ... Crafts acylation or benzoylation reactions employ acid chlorides and Lewis acids ... cyclin-dependent kinase inhibitor [14] and cysteine protease modulator.

  3. Determination of organic peroxides by liquid chromatography with on-line post-column ultraviolet irradiation and peroxyoxalate chemiluminescence detection.

    Science.gov (United States)

    Wada, Mitsuhiro; Inoue, Keiyu; Thara, Ayuko; Kishikawa, Naoya; Nakashima, Kenichiro; Kuroda, Naotaka

    2003-02-14

    A HPLC method was developed for the simultaneous determination of organic peroxides and hydrogen peroxide with peroxyoxalate chemiluminescence (PO-CL) detection following on-line UV irradiation. Organic peroxides [i.e., benzoyl peroxide (BP), tert.-butyl hydroperoxide (BHP), tert.-butyl perbenzoate (BPB), cumene hydroperoxide (CHP)] were UV irradiated (254 nm, 15 W) to generate hydrogen peroxide, which was determined by PO-CL detection. The conditions for UV irradiation and PO-CL detection were optimized by a flow injection analysis (FIA) system. Generation of hydrogen peroxide from peroxides with on-line UV irradiation also was confirmed by the FIA system by incorporating an enzyme column reactor immobilized with catalase. The separation of four organic peroxides and hydrogen peroxide by HPLC was accomplished isocratically on an ODS column within 30 min. The detection limits (signal-to-noise ratio=3) were 1.1 microM for hydrogen peroxide, 6.8 microM for BP, 31.3 microM for BHP, 7.5 microM for BPB and 1.3 microM for CHP. The proposed method was applied to the determination of BP in wheat flour.

  4. An aqueous gel fixed combination of clindamycin phosphate 1.2% and benzoyl peroxide 3.75% for the once-daily treatment of moderate to severe acne vulgaris.

    Science.gov (United States)

    Pariser, David M; Rich, Phoebe; Cook-Bolden, Fran E; Korotzer, Andrew

    2014-09-01

    To evaluate efficacy, safety, and tolerability of a fixed combination clindamycin phosphate 1.2% and benzoyl peroxide 3.75% (clindamycin-BP 3.75%) aqueous gel in moderate to severe acne vulgaris. A total of 498 patients, 12-40 years of age, were randomized to receive clindamycin-BP 3.75% or vehicle in a double-blind, controlled 12-week, 2-arm study evaluating safety and efficacy using inflammatory and noninflammatory lesion counts, Evaluator Global Severity Scores (EGSS) and subject self-assessment (SSA). In addition, patients completed a patient satisfaction survey (PSS), acne-specific QoL questionnaire, and assessed their facial skin for shininess/oiliness. Clindamycin-BP 3.75% demonstrated statistical superiority to vehicle in reducing both inflammatory and noninflammatory lesions and acne severity. Clindamycin-BP 3.75% showed greater efficacy relative to vehicle in assessments of skin oiliness, SSA and PSS. No substantive differences were seen in cutaneous tolerability among treatment groups and no patients discontinued treatment with Clindamycin-BP 3.75% because of adverse events. Data from controlled studies may differ from clinical practice. It is not possible to determine the contributions from the individual active ingredients. Clindamycin-BP 3.75% provides statistically significant greater efficacy than vehicle with a favorable safety and tolerability profile.

  5. Polymerization of aniline in an organic peroxide system by the inverted emulsion process

    OpenAIRE

    Rao, Palle Swapna; Sathyanarayana, DN; Palaniappan, S

    2002-01-01

    An inverted emulsion process for the synthesis of the emeraldine salt of polyaniline using a novel oxidizing agent, namely benzoyl peroxide, is described. The polymerization is carried out in a nonpolar solvent in the presence of a functionalized protonic acid (sulfosalicylic acid) as the dopant and an emulsifier (sodium lauryl sulfate). The influence of synthesis conditions such as the duration of the reaction, temperature, concentration of the reactants, etc., on the properties of polyanili...

  6. Regioselective Benzoylation of Diols and Carbohydrates by Catalytic Amounts of Organobase.

    Science.gov (United States)

    Lu, Yuchao; Hou, Chenxi; Ren, Jingli; Xin, Xiaoting; Xu, Hengfu; Pei, Yuxin; Dong, Hai; Pei, Zhichao

    2016-05-17

    A novel metal-free organobase-catalyzed regioselective benzoylation of diols and carbohydrates has been developed. Treatment of diol and carbohydrate substrates with 1.1 equiv. of 1-benzoylimidazole and 0.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in MeCN under mild conditions resulted in highly regioselective benzoylation for the primary hydroxyl group. Importantly, compared to most commonly used protecting bulky groups for primary hydroxyl groups, the benzoyl protective group offers a new protection strategy.

  7. Microwave-assisted facile and rapid Friedel-Crafts benzoylation of arenes catalysed by bismuth trifluoromethanesulfonate

    DEFF Research Database (Denmark)

    Tran, Phoung Hoang; Hansen, Poul Erik; Pham, Thuy Than

    2014-01-01

    The catalytic activity of metal triflates was investigated in Friedel–Crafts benzoylation under microwave irradiation. Friedel–Crafts benzoylation with benzoyl chloride of a variety of arenes containing electron-rich and electron-poor rings using bismuth triflate under microwave irradiation is de...

  8. Cocrystal solubilization in biorelevant media and its prediction from drug solubilization

    Science.gov (United States)

    Lipert, Maya P.; Roy, Lilly; Childs, Scott L.

    2015-01-01

    This work examines cocrystal solubility in biorelevant media, (FeSSIF, fed state simulated intestinal fluid), and develops a theoretical framework that allows for the simple and quantitative prediction of cocrystal solubilization from drug solubilization. The solubilities of four hydrophobic drugs and seven cocrystals containing these drugs were measured in FeSSIF and in acetate buffer at pH 5.00. In all cases, the cocrystal solubility (Scocrystal) was higher than the drug solubility (Sdrug) in both buffer and FeSSIF; however, the solubilization ratio of drug, SRdrug = (SFeSSIF/Sbuffer)drug, was not the same as the solubilization ratio of cocrystal, SRcocrystal = (SFeSSIF/Sbuffer)cocrystal, meaning drug and cocrystal were not solubilized to the same extent in FeSSIF. This highlights the potential risk of anticipating cocrystal behavior in biorelevant media based on solubility studies in water. Predictions of SRcocrystal from simple equations based only on SRdrug were in excellent agreement with measured values. For 1:1 cocrystals, the cocrystal solubilization ratio can be obtained from the square root of the drug solubilization ratio. For 2:1 cocrystals, SRcocrystal is found from (SRdrug)2/3. The findings in FeSSIF can be generalized to describe cocrystal behavior in other systems involving preferential solubilization of a drug such as surfactants, lipids, and other drug solubilizing media. PMID:26390213

  9. AuBr3-catalyzed azidation of per-O-acetylated and per-O-benzoylated sugars.

    Science.gov (United States)

    Rajput, Jayashree; Hotha, Srinivas; Vangala, Madhuri

    2018-01-01

    Herein we report, for the first time, the successful anomeric azidation of per- O -acetylated and per- O -benzoylated sugars by catalytic amounts of oxophilic AuBr 3 in good to excellent yields. The method is applicable to a wide range of easily accessible per- O -acetylated and per- O -benzoylated sugars. While reaction with per- O -acetylated and per- O -benzoylated monosaccharides was complete within 1-3 h at room temperature, the per- O -benzoylated disaccharides needed 2-3 h of heating at 55 °C.

  10. Characterization of Benzoyl Coenzyme A Biosynthesis Genes in the Enterocin-Producing Bacterium “Streptomyces maritimus”

    Science.gov (United States)

    Xiang, Longkuan; Moore, Bradley S.

    2003-01-01

    The novel benzoyl coenzyme A (benzoyl-CoA) biosynthesis pathway in “Streptomyces maritimus” was investigated through a series of target-directed mutations. Genes involved in benzoyl-CoA formation were disrupted through single-crossover homologous recombination, and the resulting mutants were analyzed for their ability to biosynthesize the benzoyl-CoA-primed polyketide antibiotic enterocin. Inactivation of the unique phenylalanine ammonia-lyase-encoding gene encP was previously shown to be absolutely required for benzoyl-CoA formation in “S. maritimus”. The fatty acid β-oxidation-related genes encH, -I, and -J, on the other hand, are necessary but not required. In each case, the yield of benzoyl-CoA-primed enterocin dropped below wild-type levels. We attribute the reduced benzoyl-CoA formation in these specific mutants to functional substitution and cross-talk between the products of genes encH, -I, and -J and the enzyme homologues of primary metabolism. Disruption of the benzoate-CoA ligase encN gene did not perturb enterocin production, however, demonstrating that encN is extraneous and that benzoic acid is not a pathway intermediate. EncN rather serves as a substitute pathway for utilizing exogenous benzoic acid. These experiments provide further support that benzoyl-CoA is formed in a novel bacterial pathway that resembles the eukaryotic assembly of benzoyl-CoA from phenylalanine via a β-oxidative path. PMID:12511484

  11. Formulation and evaluation of a topical niosomal gel containing a combination of benzoyl peroxide and tretinoin for antiacne activity

    Science.gov (United States)

    Gupta, Ankush; Singh, Sima; Kotla, Niranjan G; Webster, Thomas J

    2015-01-01

    A skin disease, like acne, is very common and normally happens to everyone at least once in their lifetime. The structure of the stratum corneum is often compared with a brick wall, with corneocytes surrounded by the mortar of the intercellular lipid lamellae. One of the best options for successful drug delivery to the affected area of skin is the use of elastic vesicles (niosomes) which can be transported through the skin through channel-like structures. In this study, a combination of tretinoin (keratolytic agent) and benzoyl peroxide (BPO) (a potent antibacterial) was given by using niosomes as promising carriers for the effective treatment of acne by acting on a pathogenic site. In this section, niosomal gel formulation encapsulated drugs have been evaluated for in vitro, ex vivo, and in vivo, for their predetermined characteristics; and finally the stability of the niosome gel was tested at different temperature conditions for understanding of the storage conditions required for maintaining the quality of formulation attributes. The prepared niosome was found to be in the range of 531 nm with a zeta potential of −43 mV; the entrapment efficiencies of tretinoin (TRA) and BPO niosomes were found to be 96.25%±0.56% and 98.75%±1.25%, respectively. The permeated amount of TRA and BPO from the niosomal gel after 24 hours was calculated as 6.25±0.14 μg/cm2 and 5.04±0.014 μg/cm2, respectively. A comparative drug retention study in Wistar rat skin using cream, an alcoholic solution, and a niosomal gel showed 11.54 μg, 2.68 μg, and 15.54 μg amounts of TRA and 68.85 μg, 59.98 μg, and 143.78 μg amounts of BPO were retained in the layers of skin, respectively. In vivo studies of the niosomal gel and antiacne cream of TRA and BPO showed that the niosomal gel was more efficacious than the antiacne cream because niosomal gels with a 4.16-fold lower dose of BPO provided the same therapeutic index at targeted sites in comparison to the antiacne cream. PMID

  12. Formulation and evaluation of a topical niosomal gel containing a combination of benzoyl peroxide and tretinoin for antiacne activity.

    Science.gov (United States)

    Gupta, Ankush; Singh, Sima; Kotla, Niranjan G; Webster, Thomas J

    2015-01-01

    A skin disease, like acne, is very common and normally happens to everyone at least once in their lifetime. The structure of the stratum corneum is often compared with a brick wall, with corneocytes surrounded by the mortar of the intercellular lipid lamellae. One of the best options for successful drug delivery to the affected area of skin is the use of elastic vesicles (niosomes) which can be transported through the skin through channel-like structures. In this study, a combination of tretinoin (keratolytic agent) and benzoyl peroxide (BPO) (a potent antibacterial) was given by using niosomes as promising carriers for the effective treatment of acne by acting on a pathogenic site. In this section, niosomal gel formulation encapsulated drugs have been evaluated for in vitro, ex vivo, and in vivo, for their predetermined characteristics; and finally the stability of the niosome gel was tested at different temperature conditions for understanding of the storage conditions required for maintaining the quality of formulation attributes. The prepared niosome was found to be in the range of 531 nm with a zeta potential of -43 mV; the entrapment efficiencies of tretinoin (TRA) and BPO niosomes were found to be 96.25%±0.56% and 98.75%±1.25%, respectively. The permeated amount of TRA and BPO from the niosomal gel after 24 hours was calculated as 6.25±0.14 μg/cm(2) and 5.04±0.014 μg/cm(2), respectively. A comparative drug retention study in Wistar rat skin using cream, an alcoholic solution, and a niosomal gel showed 11.54 μg, 2.68 μg, and 15.54 μg amounts of TRA and 68.85 μg, 59.98 μg, and 143.78 μg amounts of BPO were retained in the layers of skin, respectively. In vivo studies of the niosomal gel and antiacne cream of TRA and BPO showed that the niosomal gel was more efficacious than the antiacne cream because niosomal gels with a 4.16-fold lower dose of BPO provided the same therapeutic index at targeted sites in comparison to the antiacne cream.

  13. Benzoylated Uronic Acid Building Blocks and Synthesis of N-Uronate Conjugates of Lamotrigine

    Directory of Open Access Journals (Sweden)

    Bård Helge Hoff

    2012-01-01

    Full Text Available A chemoenzymatic approach towards benzoylated uronic acid building blocks has been investigated starting with benzoylated hexapyranosides using regioselective C-6 enzymatic hydrolysis as the key step. Two of the building blocks were reacted with the antiepileptic drug lamotrigine. Glucuronidation of lamotrigine using methyl (2,3,4-tri-O-benzoyl-α-D-glycopyranosyl bromideuronate proceeded to give the N2-conjugate. However, lamotrigine-N2-glucuronide was most efficiently synthesised from methyl (2,3,4-tri-O-acetyl-α-D-glucopyranosyl bromideuronate. Employing nitromethane as solvent with CdCO3 as a base lamotrigine-N2 glucuronide was prepared in a high yield (41%. Also methyl (2,3-di-O-benzoyl-4-deoxy-4-fluoro-α-D-glucosyl bromideuronate underwent N-glucuronidation, but the product was unstable, eliminating hydrogen fluoride to give the corresponding enoate conjugate.

  14. A cold active (2R,3R)-(-)-di-O-benzoyl-tartrate hydrolyzing esterase from Rhodotorula mucilaginosa.

    Science.gov (United States)

    Zimmer, Christian; Platz, Tanja; Cadez, Neza; Giffhorn, Friedrich; Kohring, Gert-Wieland

    2006-11-01

    In a screening procedure a pink-colored yeast was isolated from enrichment cultures with (2R,3R)-(-)-di-O-benzoyl-tartrate (benzoyl-tartrate) as the sole carbon source. The organism saar1 was identified by morphological, physiological, and 18S ribosomal DNA/internal transcribed spacer analysis as Rhodotorula mucilaginosa, a basidiomycetous yeast. During growth the yeast hydrolyzed the dibenzoyl ester stoichiometrically to the monoester using the separated benzoate as the growth substrate, before the monoester was further cleaved into benzoate and tartrate, which were both metabolized. The corresponding benzoyl esterase was purified from the culture supernatant and characterized as a monomeric glycosylated 86-kDa protein with an optimum pH of 7.5 and an optimum temperature of 45 degrees C. At 0 degrees C the esterase still exhibited 20% of the corresponding activity at 30 degrees C, which correlates it to psychrophilic enzymes. The esterase could hydrolyze short chain p-nitrophenyl-alkyl esters and several benzoyl esters like benzoyl-methyl ester, ethylene-glycol-dibenzoyl ester, phenyl-benzoyl ester, cocaine, and 1,5-anhydro-D: -fructose-tribenzoyl ester. However feruloyl-ethyl ester was not hydrolyzed. The activity characteristics let the enzyme appear as a promising tool for synthesis of benzoylated compounds for pharmaceutical, cosmetic, or fine chemical applications, even at low temperatures.

  15. X-ray investigations of sulfur-containing fungicides. IV. 4'-[[Benzoyl(4-chlorophenylhydrazono)methyl]sulfonyl]acetanilide and 4'-[[benzoyl(4-methoxyphenylhydrazono)methyl]sulfonyl]acetanilide.

    Science.gov (United States)

    Wolf, W M

    2001-09-01

    The conformations of the two approximately isomorphous structures 4'-[[benzoyl(4-chlorophenylhydrazono)methyl]sulfonyl]acetanilide, C(22)H(18)ClN(3)O(4)S, and 4'-[[benzoyl(4-methoxyphenylhydrazono)methyl]sulfonyl]acetanilide, C(23)H(21)N(3)O(5)S, are stabilized by resonance-assisted intramolecular hydrogen bonds linking the hydrazone moieties and sulfonyl groups. The stronger bond is observed in the former compound. The difference in electronic properties between the Cl atom and the methoxy group is too small to significantly alter the non-bonding interactions of the sulfonyl and beta-carbonyl groups.

  16. Twelve-week, multicenter, placebo-controlled, randomized, double-blind, parallel-group, comparative phase II/III study of benzoyl peroxide gel in patients with acne vulgaris: A secondary publication.

    Science.gov (United States)

    Kawashima, Makoto; Sato, Shinichi; Furukawa, Fukumi; Matsunaga, Kayoko; Akamatsu, Hirohiko; Igarashi, Atsuyuki; Tsunemi, Yuichiro; Hayashi, Nobukazu; Yamamoto, Yuki; Nagare, Toshitaka; Katsuramaki, Tsuneo

    2017-07-01

    A placebo-controlled, randomized, double-blind, parallel-group, comparative, multicenter study was conducted to investigate the efficacy and safety of benzoyl peroxide (BPO) gel, administrated once daily for 12 weeks to Japanese patients with acne vulgaris. Efficacy was evaluated by counting all inflammatory and non-inflammatory lesions. Safety was evaluated based on adverse events, local skin tolerability scores and laboratory test values. All 609 subjects were randomly assigned to receive the study products (2.5% and 5% BPO and placebo), and 607 subjects were included in the full analysis set, 544 in the per protocol set and 609 in the safety analyses. The median rates of reduction from baseline to the last evaluation of the inflammatory lesion counts, the primary end-point, in the 2.5% and 5% BPO groups were 72.7% and 75.0%, respectively, and were significantly higher than that in the placebo group (41.7%). No deaths or other serious adverse events were observed. The incidences of adverse events in the 2.5% and 5% BPO groups were 56.4% and 58.8%, respectively; a higher incidence than in the placebo group, but there was no obvious difference between the 2.5% and 5% BPO groups. All adverse events were mild or moderate in severity. Most adverse events did not lead to study product discontinuation. The results suggested that both 2.5% and 5% BPO are useful for the treatment of acne vulgaris. © 2017 The Authors. The Journal of Dermatology published by John Wiley & Sons Australia, Ltd.

  17. Formulation and evaluation of a topical niosomal gel containing a combination of benzoyl peroxide and tretinoin for antiacne activity

    Directory of Open Access Journals (Sweden)

    Gupta A

    2014-12-01

    Full Text Available Ankush Gupta,1,* Sima Singh,1,* Niranjan G Kotla,1 Thomas J Webster2,3 1Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India; 2Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 3Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia *These authors contributed equally to this work Abstract: A skin disease, like acne, is very common and normally happens to everyone at least once in their lifetime. The structure of the stratum corneum is often compared with a brick wall, with corneocytes surrounded by the mortar of the intercellular lipid lamellae. One of the best options for successful drug delivery to the affected area of skin is the use of elastic vesicles (niosomes which can be transported through the skin through channel-like structures. In this study, a combination of tretinoin (keratolytic agent and benzoyl peroxide (BPO (a potent antibacterial was given by using niosomes as promising carriers for the effective treatment of acne by acting on a pathogenic site. In this section, niosomal gel formulation encapsulated drugs have been evaluated for in vitro, ex vivo, and in vivo, for their predetermined characteristics; and finally the stability of the niosome gel was tested at different temperature conditions for understanding of the storage conditions required for maintaining the quality of formulation attributes. The prepared niosome was found to be in the range of 531 nm with a zeta potential of -43 mV; the entrapment efficiencies of tretinoin (TRA and BPO niosomes were found to be 96.25%±0.56% and 98.75%±1.25%, respectively. The permeated amount of TRA and BPO from the niosomal gel after 24 hours was calculated as 6.25±0.14 µg/cm2 and 5.04±0.014 µg/cm2, respectively. A comparative drug retention study in Wistar rat skin using cream, an alcoholic solution, and a niosomal gel showed 11.54 µg, 2.68 µg, and 15.54 µg

  18. Photoaffinity labeling of myosin subfragment-one-with 3'(2')-O-(4-benzoyl)benzoyl adenosine 5'-triphosphate

    International Nuclear Information System (INIS)

    Mahmood, R.

    1985-01-01

    The photoaffinity analogue 3'(2')-O-(4-benzoyl)benzoyl adenosine 5'-triphosphate (Bz 2 ATP) contains the photoreactive benzophenone group esterified at the 2' or 3' hydroxyl groups of ribose. MgBz 2 ADP has a single binding site on skeletal myosin chymotryptic subfragment-one (SF 1 ) with a binding constant of 3.2 x 10 5 M -1 . Bz 2 ATP is also a substrate for the ATPase activity of SF 1 in the presence of different cations. The irradiation of SF 1 with [ 3 H]Bz 2 ATP photoinactivates the ATPase activity with concomitant incorporation of the analogue into the enzyme. Polyacrylamide gel electrophoresis of photolabeled SF 1 after milk trypsin digestion shows that all three tryptic peptides, 25 K, 50K, and 20 K, and both light chains are labeled. The presence of ATP during irradiation reduces labeling of the 50 K peptide only indicating that the other peptides are non-specifically labeled. To reduce the non-specific labeling [ 3 H]Bz 2 ATP is trapped on SF 1 by cross-linking the two reactive thiols, SH 1 and SH 2 , by N,N'-p-phenylene dimaleimide or Co(II)/Co(III) phenanthroline complexes. The Co(II)/Co(III) phenanthroline modified [ 14 C]Bz 2 ATP-SF 1 , after proteolytic digestion, yields five labeled peptides which were purified by gel filtration and high performance liquid chromatography

  19. Solar-Driven Hydrogen Peroxide Production Using Polymer-Supported Carbon Dots as Heterogeneous Catalyst

    Science.gov (United States)

    Gogoi, Satyabrat; Karak, Niranjan

    2017-10-01

    Safe, sustainable, and green production of hydrogen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV, which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium. The overall process was performed in accordance with the principles of green chemistry using bio-based precursors and aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.

  20. Correlations between retention indices and molecular structure of their benzoyl derivatives on phenyl substituted polysiloxane stationary phases

    International Nuclear Information System (INIS)

    Pias, J.B.; Gasco, L.

    1976-01-01

    The retention indices of aliphaticalcohols of carbon number up to Csub(g), and of their benzoyl derivatives up to C 7 , were determined in columns packed with Chromosorb G (AW-DMCS-HP) coated previously with 5% methyl, and methyl phenyl polysiloxanes with increasing polarity (SE-30, OV-3, OV-7; OV-11, OV-17 and OV-25). Correlations between retention indices and chain length for 1-alcohols, 2-alcohols, 3-alcohols, 1, on -3-alcohols, 2-methyl-1-alcohols and for their corresponding benzoyl derivatives were calculated at 100, 120 and 140 0 C. In alcohols, a -CH 2 - group increases I approximately 100 units, and in their benzoyl derivatives from 80 to 100 units. Dispersion indices ΔI, and positional and structural increments of I were evaluated for -OH and benzoyl groups in terms for phase polarity and chain length. Effects of chain length, chain branching and double bond location on retention parameters were also studied. (author)

  1. Complement-mediated solubilization of immune complexes. Solubilization inhibition and complement factor levels in SLE patients

    DEFF Research Database (Denmark)

    Baatrup, Gunnar; Petersen, Ivan; Kappelgaard, E

    1984-01-01

    Thirty-two of 36 serum samples from 19 SLE patients showed reduced capacity to mediate complement-dependent solubilization of immune complexes (IC). SLE patients with nephritis exerted the lowest complement-mediated solubilization capacity (CMSC) whereas sera from patients with inactive disease g...

  2. Sewage sludge solubilization by high-pressure homogenization.

    Science.gov (United States)

    Zhang, Yuxuan; Zhang, Panyue; Guo, Jianbin; Ma, Weifang; Fang, Wei; Ma, Boqiang; Xu, Xiangzhe

    2013-01-01

    The behavior of sludge solubilization using high-pressure homogenization (HPH) treatment was examined by investigating the sludge solid reduction and organics solubilization. The sludge volatile suspended solids (VSS) decreased from 10.58 to 6.67 g/L for the sludge sample with a total solids content (TS) of 1.49% after HPH treatment at a homogenization pressure of 80 MPa with four homogenization cycles; total suspended solids (TSS) correspondingly decreased from 14.26 to 9.91 g/L. About 86.15% of the TSS reduction was attributed to the VSS reduction. The increase of homogenization pressure from 20 to 80 MPa or homogenization cycle number from 1 to 4 was favorable to the sludge organics solubilization, and the protein and polysaccharide solubilization linearly increased with the soluble chemical oxygen demand (SCOD) solubilization. More proteins were solubilized than polysaccharides. The linear relationship between SCOD solubilization and VSS reduction had no significant change under different homogenization pressures, homogenization cycles and sludge solid contents. The SCOD of 1.65 g/L was solubilized for the VSS reduction of 1.00 g/L for the three experimental sludge samples with a TS of 1.00, 1.49 and 2.48% under all HPH operating conditions. The energy efficiency results showed that the HPH treatment at a homogenization pressure of 30 MPa with a single homogenization cycle for the sludge sample with a TS of 2.48% was the most energy efficient.

  3. Supra-molecular hydrogen-bonding patterns in the N(9)-H protonated and N(7)-H tautomeric form of an N(6) -benzoyl-adenine salt: N (6)-benzoyl-adeninium nitrate.

    Science.gov (United States)

    Karthikeyan, Ammasai; Jeeva Jasmine, Nithianantham; Thomas Muthiah, Packianathan; Perdih, Franc

    2016-02-01

    In the title molecular salt, C12H10N5O(+)·NO3 (-), the adenine unit has an N (9)-protonated N(7)-H tautomeric form with non-protonated N(1) and N(3) atoms. The dihedral angle between the adenine ring system and the phenyl ring is 51.10 (10)°. The typical intra-molecular N(7)-H⋯O hydrogen bond with an S(7) graph-set motif is also present. The benzoyl-adeninium cations also form base pairs through N-H⋯O and C-H⋯N hydrogen bonds involving the Watson-Crick face of the adenine ring and the C and O atoms of the benzoyl ring of an adjacent cation, forming a supra-molecular ribbon with R 2 (2)(9) rings. Benzoyl-adeninum cations are also bridged by one of the oxygen atoms of the nitrate anion, which acts as a double acceptor, forming a pair of N-H⋯O hydrogen bonds to generate a second ribbon motif. These ribbons together with π-π stacking inter-actions between the phenyl ring and the five- and six-membered adenine rings of adjacent mol-ecules generate a three-dimensional supra-molecular architecture.

  4. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  5. Open-label, randomized, multicenter, phase III study to evaluate the safety and efficacy of benzoyl peroxide gel in long-term use in patients with acne vulgaris: A secondary publication.

    Science.gov (United States)

    Kawashima, Makoto; Nagare, Toshitaka; Katsuramaki, Tsuneo

    2017-06-01

    An open-label, randomized, multicenter study was conducted to evaluate the safety and efficacy of long-term use of 2.5% and 5% benzoyl peroxide (BPO) gels administrated once daily for 52 weeks to Japanese patients with acne vulgaris. The efficacy of the study drugs was evaluated by counting inflammatory lesions and non-inflammatory lesions. Safety was evaluated based on adverse events, local skin tolerability scores and laboratory test values. In total, 458 subjects were included in the efficacy and safety analyses. The total lesion count, the efficacy end-point, was similarly changed both in the 2.5% and 5% BPO groups over the course of the study. The median rates of reduction from baseline to week 12 were approximately 65%. Thereafter, the counts were maintained at a reduced level without increasing until week 52. The median rates at week 52 were approximately 80%. Similar trends were observed for inflammatory and non-inflammatory lesion counts. Bacteriological evaluation indicated similar distribution of the minimum inhibitory concentration of each of the antibacterial drugs against Propionibacterium acnes between the values at baseline and at week 52, suggesting that long-term use did not result in changes in the drug sensitivity. The incidence of adverse events was 84.0% in the 2.5% BPO group and 87.2% in the 5% BPO group. Many of the adverse events occurred within the first month and were mild or moderate in severity and transient. The results suggest that both 2.5% and 5% BPO gels are effective and safe for long-term treatment of patients with acne vulgaris. © 2017 The Authors. The Journal of Dermatology published by John Wiley & Sons Australia, Ltd on behalf of Japanese Dermatological Association.

  6. Isolation and screening phosphate solubilizers from composts as biofertilizer

    International Nuclear Information System (INIS)

    Phua Choo Kwai Hoe; Khairuddin Abdul Rahim; Latiffah Norddin; Abdul Razak Ruslan

    2006-01-01

    Phosphate solubilizers are miroorganisms that able to solubilize insoluble inorganic phosphate compounds or hydrolyze organic phosphate to inorganic P. Therefore make the P to be available for plant and consequently enhance plant growth and yield. Recently, phosphate solubilizing microorganisms has been shown to play an important role in the biofertilizer industry. Fifty-one bacterial were isolated from eleven composts. Most of the phosphate solubilizers were isolated from natural farming composted compost and normal composting compost. This shows that both of these composts are more suitable to use for phosphate solubilizer isolation compare commercial composts. Fourteen of the isolates were found to be phosphate solubilizers. These isolates produced a clear zone on the phosphate agar plates, showing their potential as biofertilizer. AP3 was significantly produced the largest clear zone compared with other isolates. This indicates that isolate AP 3 could be a good phosphate solubilizer. Thus, their effectiveness in the greenhouse and field should be evaluated. (Author)

  7. Solubilization of Hydrophobic Dyes in Surfactant Solutions

    Directory of Open Access Journals (Sweden)

    Ali Reza Tehrani-Bagha

    2013-02-01

    Full Text Available In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.

  8. Chemoselective C-benzoylation of phenols by using AlCl3 under ...

    African Journals Online (AJOL)

    Substituted phenols were chemo-selectively reacted with benzoylchloride in presence of aluminum chloride under solvent-free condition to afford the corresponding 2'-hydroxy aryl benzophenones in excellent yields (72-96%). Naphthol benzoylation resulted in lower yields as compared to phenols. Both reactions ...

  9. The 2-(acetoxymethyl)benzoyl (AMB) group as a new base-protecting group, designed for the protection of (phosphate) modified oligonucleotides.

    NARCIS (Netherlands)

    Kuijpers, W.H.A.; Huskens, J.; Boeckel, van C.A.A.

    1990-01-01

    The 2-(acetoxymethyl)benzoyl (AMB) group is a new base-protecting group that facilitates the synthesis of labile, modified nucleotides, since it can be rapidly cleaved under mild basic conditions. The 2-(acetoxymethyl)benzoyl (AMB) group is a new base-protecting group that facilitates the synthesis

  10. Solubilization and purification of melatonin receptors from lizard brain

    International Nuclear Information System (INIS)

    Rivkees, S.A.; Conron, R.W. Jr.; Reppert, S.M.

    1990-01-01

    Melatonin receptors in lizard brain were identified and characterized using 125 I-labeled melatonin ([ 125 I]MEL) after solubilization with the detergent digitonin. Saturation studies of solubilized material revealed a high affinity binding site, with an apparent equilibrium dissociation constant of 181 +/- 45 pM. Binding was reversible and inhibited by melatonin and closely related analogs, but not by serotonin or norepinephrine. Treatment of solubilized material with the non-hydrolyzable GTP analog, guanosine 5'-(3-O-thiotriphosphate) (GTP-gamma-S), significantly reduced receptor affinity. Gel filtration chromatography of solubilized melatonin receptors revealed a high affinity, large (Mr 400,000) peak of specific binding. Pretreatment with GTP-gamma-S before solubilization resulted in elution of a lower affinity, smaller (Mr 150,000) peak of specific binding. To purify solubilized receptors, a novel affinity chromatography resin was developed by coupling 6-hydroxymelatonin with Epoxy-activated Sepharose 6B. Using this resin, melatonin receptors were purified approximately 10,000-fold. Purified material retained the pharmacologic specificity of melatonin receptors. These results show that melatonin receptors that bind ligand after detergent treatment can be solubilized and substantially purified by affinity chromatography

  11. Solubilization and purification of melatonin receptors from lizard brain.

    Science.gov (United States)

    Rivkees, S A; Conron, R W; Reppert, S M

    1990-09-01

    Melatonin receptors in lizard brain were identified and characterized using 125I-labeled melatonin ([125I]MEL) after solubilization with the detergent digitonin. Saturation studies of solubilized material revealed a high affinity binding site, with an apparent equilibrium dissociation constant of 181 +/- 45 pM. Binding was reversible and inhibited by melatonin and closely related analogs, but not by serotonin or norepinephrine. Treatment of solubilized material with the non-hydrolyzable GTP analog, guanosine 5'-(3-O-thiotriphosphate) (GTP-gamma-S), significantly reduced receptor affinity. Gel filtration chromatography of solubilized melatonin receptors revealed a high affinity, large (Mr 400,000) peak of specific binding. Pretreatment with GTP-gamma-S before solubilization resulted in elution of a lower affinity, smaller (Mr 150,000) peak of specific binding. To purify solubilized receptors, a novel affinity chromatography resin was developed by coupling 6-hydroxymelatonin with Epoxy-activated Sepharose 6B. Using this resin, melatonin receptors were purified approximately 10,000-fold. Purified material retained the pharmacologic specificity of melatonin receptors. These results show that melatonin receptors that bind ligand after detergent treatment can be solubilized and substantially purified by affinity chromatography.

  12. An efficient method for qualitative screening of phosphate-solubilizing bacteria.

    Science.gov (United States)

    Mehta, S; Nautiyal, C S

    2001-07-01

    An efficient protocol was developed for qualitative screening of phosphate-solubilizing bacteria, based upon visual observation. Our results indicate that, by using our formulation containing bromophenol blue, it is possible to quickly screen on a qualitative basis the phosphate-solubilizing bacteria. Qualitative analysis of the phosphate solubilized by various groups correlated well with grouping based upon quantitative analysis of bacteria isolated from soil, effect of carbon, nitrogen, salts, and phosphate solubilization-defective transposon mutants. However, unlike quantitative analysis methods that involve time-consuming biochemical procedures, the time for screening phosphate-solubilizing bacteria is significantly reduced by using our simple protocol. Therefore, it is envisaged that usage of this formulation based upon qualitative analysis will be salutary for the quick screening of phosphate-solubilizing bacteria. Our results indicate that the formulation can also be used as a quality control test for expeditiously screening the commercial bioinoculant preparations, based on phosphate solubilizers.

  13. Synthesis, physico-chemical characterization and biological activity of copper(ii and nickel(ii complexes with l-benzoyl-2-methylbenzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    Podunavac-Kuzmanović Sanja O.

    2002-01-01

    Full Text Available Chlorides of copper(II and nickel(ll react with 1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl-2-methylbenzimidazole to give complexes of the type [M(LnCln(H20∙Cln (M = Cu or Ni; L = (1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl-2-methylbenzimidazole; n=O, 1 or 2. The complexes were synthesized and characterized by elemental analysis, molar conductivity magnetic susceptibility measurements and IR spectra. These studies suggest that all the complexes possess an octahedral stereochemistry. The antibacterial activity of (1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl-2-methylbenzimidazole and their complexes was evaluated against Escherichia coli and Bacillus sp.

  14. Greener Friedel-Crafts Acylation using Microwave-enhanced reactivity of Bismuth Triflate in the Friedel-Crafts Benzoylation of Aromatic Compounds with Benzoic Anhydride

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Nguyen, Hai Truong; Hansen, Poul Erik

    2017-01-01

    An efficient and facile bismuth trifluoromethanesulfonate-catalyzed benzoylation of aromatic compounds using benzoic anhydride under solvent-free microwave irradiation has been developed. The microwave-assisted Friedel-Crafts benzoylation results in good yields within short reaction times. Bismuth...

  15. N-Benzoyl-2-nitrobenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    P. A. Suchetan

    2012-02-01

    Full Text Available In the title compound, C13H10N2O5S, the N—C bond in the C—SO2—NH—C segment has gauche torsion angles with respect to the S=O bonds. The conformation between the N—H bond and the ortho-nitro group in the sulfonyl benzene ring is syn. The molecule is twisted at the S—N bond with a torsion angle of −63.4 (2°. The sulfonyl benzene ring is tilted by 77.1 (1° relative to the —SO2—NH—C—O segment. The dihedral angle between the sulfonyl and the benzoyl benzene rings is 88.6 (1°. In the crystal, pairs of N—H...O(S hydrogen bonds link the molecules into inversion dimers, which are linked by weak C—H...O and C—H...π interactions along the b axis.

  16. Correlations Between retention indices and molecular structure of aliphatic alcohols and of their benzoyl derivatives on phenyl substituted polysiloxane stationary phases

    International Nuclear Information System (INIS)

    Pias, J. B.; Gasco, L.

    1976-01-01

    The retention indices of aliphatic alcohols of carbon number up to C g , and of their benzoyl derivatives up to C 7 , were determined in columns packed with Chromo sorb G (AW-DMCS-HP) coated previously with 5% methyl, and methyl phenyl polysiloxanes with increasing polarity (SE-30, 0V-3, 0V-7, 0V-11, 0V-17 and OV-25). Correlations between retention indices and chain length for 1-alcohols, 2-alcohols, 3-alcohols, 1 , on -3-alcohols, 2-methyl-1-alcohols and for their corresponding benzoyl derivatives were calculated at 100, 120 and 140 degree centigree. In alcohols, a -CH 2 - group increases I approximately 100 units, and in their benzoyl derivatives from 80 to 100 units. Dispersion indices Δl , and positional and structural increments δI, were evaluated for -OH and benzoyl groups in terms of phase polarity and chain length. Effects of chain length, chain branching and double bond location on retention parameters were also studied. (Author) 23 refs

  17. Research and engineering assessment of biological solubilization of phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, R.D.; McIlwain, M.E.; Losinski, S.J.; Taylor, D.D.

    1993-03-01

    This research and engineering assessment examined a microbial phosphate solubilization process as a method of recovering phosphate from phosphorus containing ore compared to the existing wet acid and electric arc methods. A total of 860 microbial isolates, collected from a range of natural environments were tested for their ability to solubilize phosphate from rock phosphate. A bacterium (Pseudomonas cepacia) was selected for extensive characterization and evaluation of the mechanism of phosphate solubilization and of process engineering parameters necessary to recover phosphate from rock phosphate. These studies found that concentration of hydrogen ion and production of organic acids arising from oxidation of the carbon source facilitated microbial solubilization of both pure chemical insoluble phosphate compounds and phosphate rock. Genetic studies found that phosphate solubilization was linked to an enzyme system (glucose dehydrogenase). Process-related studies found that a critical solids density of 1% by weight (ore to liquid) was necessary for optimal solubilization. An engineering analysis evaluated the cost and energy requirements for a 2 million ton per year sized plant, whose size was selected to be comparable to existing wet acid plants.

  18. Solubilization of paraffinic deposits for microemulsions

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Erika A.S.; Soares, Ranieri G.F.; Nascimento, Roseane E.S.; Dantas Neto, Afonso A.; Barros Neto, Eduardo L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    The oil company has been intensifying its efforts to find more efficient solutions for the problems related to the paraffin in wells and transport lines. When applied in the flow lines, the solvents dissolve the paraffin and they must be used hot, since the temperature increases the solubility of the wax and, consequently, its removal rate. The microemulsions appear as an alternative capable of acting in the solubilization and in the inhibition of the formation of deposits due to its great interfacial area, low superficial tension and high capacity of solubilization. They present some advantages in relation to the methods of use of chemical products due to its flexibility of composition in which they can be used, presenting low toxicity and inflammability, without any loss of its capacity of solubilization. The use of oil-in-water microemulsion aims to solubilized paraffin in the disperse phase, where one can find the apolar part of the molecule of the surfactant and the also apolar chain of paraffin, occurring, therefore the 'encapsulation' of the crystal, prohibiting the growth of the chain due to the affinity of paraffin and oil. In this in case, it is possible to transport the inserted paraffin in direct micelles, reducing the precipitation and optimizing the transport. (author)

  19. Rock phosphate solubilization by the ectomycorrhizal fungus ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... To evaluate phosphate solubilization of ... and MHB had the potential to solubilize these phosphates by decreasing the pH and confirmed that ... Minerals like N, P, K, Ca, S, Zn, Cu and Sr are ... sterile distilled water, chopped, homogenized in 10 ml sterile .... The role of carbon source is important in mineral.

  20. Synthesis, screening and QSAR studies of 3-benzoyl-2-oxo/thioxo-1 ...

    African Journals Online (AJOL)

    5-Acyl-6-methyl-4-substituted-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidines (A) were synthesized by cyclocondensation reaction between appropriate aldehyde, acetoacetate and urea/thiourea in presence of aluminium chloride and hydrochloric acid which upon treatment with benzoyl chloride in presence of pyridine in ...

  1. Phosphate-Solubilizing and -Mineralizing Abilities of Bacteria Isolated from Soils

    Institute of Scientific and Technical Information of China (English)

    TAO Guang-Can; TIAN Shu-Jun; CAI Miao-Ying; XIE Guang-Hui

    2008-01-01

    Microorganisms capable of solubilizing and mineralizing phosphorus (P) pools in soils are considered vital in promoting P bioavailability. The study was conducted to screen and isolate inorganic P-solubilizing bacteria (IPSB) and organic P-mineralizing bacteria (OPMB) in soils taken from subtropical flooded and temperate non-flooded soils, and to compare inorganic P-solubilizing and organic P-solubilizing abilities between IPSB and OPMB. Ten OPMB strains were isolated and identified as Bacillus cereus and Bacillus megaterium, and five IPSB strains as B. megaterium, Burkholderia caryophylli,Pseudomonas ciehorii, and Pseudomonas syringae. P-solubilizing and -mineralizing abilities of the strains were measured using the methods taking cellular P into account. The IPSB strains exhibited inorganic P-sohibilizing abilities ranging between 25.4-41.7 μg P mL-1 and organic P-mineralizing abilities between 8.2-17.8 μg P mL-1. Each of the OPMB strains also exhibited both solubilizing and mineralizing abilities varying from 4.4 to 26.5 μg P mL-1 and from 13.8 to 62.8 μg P mL-1, respectively. For both IPSB and OPMB strains, most of the P mineralized from the organic P source was incorporated into the bacterial cells as cellular P. A significantly negative linear correlation (P < 0.05) was found between culture pH and P solubilized from inorganic P by OPMB strains. The results suggested that P solubilization and mineralization could coexist in the same bacterial strain.

  2. HPMA-based polymeric micelles for curcumin solubilization and inhibition of cancer cell growth.

    Science.gov (United States)

    Naksuriya, Ornchuma; Shi, Yang; van Nostrum, Cornelus F; Anuchapreeda, Songyot; Hennink, Wim E; Okonogi, Siriporn

    2015-08-01

    Curcumin (CM) has been reported as a potential anticancer agent. However, its pharmaceutical applications as therapeutic agent are hampered because of its poor aqueous solubility. The present study explores the advantages of polymeric micelles composed of block copolymers of methoxypoly(ethylene glycol) (mPEG) and N-(2-hydroxypropyl) methacrylamide (HPMA) modified with monolactate, dilactate and benzoyl side groups to enhance CM solubility and inhibitory activity against cancer cells. Amphiphilic block copolymers, ω-methoxypoly(ethylene glycol)-b-(N-(2-benzoyloxypropyl) methacrylamide) (PEG-HPMA-Bz) were synthesized and characterized by (1)H NMR and GPC. One polymer with a molecular weight of 28,000Da was used to formulate CM and compared with other aromatic substituted polymers. CM was loaded by a fast heating method (PEG-HPMA-DL and PEG-HPMA-Bz-L) and a nanoprecipitation method (PEG-HPMA-Bz). Physicochemical characteristics and cytotoxicity/cytocompatibility of the CM loaded polymeric micelles were evaluated. It was found that HPMA-based polymeric micelles significantly enhanced the solubility of CM. The PEG-HPMA-Bz micelles showed the best solubilization properties. CM loaded polymeric micelles showed sustained release of the loading CM for more than 20days. All of CM loaded polymeric micelles formulations showed a significantly potent cytotoxic effect against three cancer cell lines. HPMA-based polymeric micelles are therefore promising nanodelivery systems of CM for cancer therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Solubilization properties of polycyclic aromatic hydrocarbons by saponin, a plant-derived biosurfactant

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Wenjun, E-mail: wenjunzhou@zju.edu.cn [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310028 (China); Yang Juanjuan; Lou Linjie [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310028 (China)

    2011-05-15

    The enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) by saponin, a plant-derived non-ionic biosurfactant, was investigated. The results indicated that the solubilization capabilities of saponin for PAHs were greater than some representative synthetic non-ionic surfactants and showed strong dependence on solution pH and ionic strength. The molar solubilization ratio (MSR) of saponin for phenanthrene was about 3-6 times of those of the synthetic non-ionic surfactants, and decreased by about 70% with the increase of solution pH from 4.0 to 8.0, but increased by approximately 1 times with NaCl concentration increased from 0.01 to 1.0 M. Heavy metal ions can enhance saponin solubilization for phenanthrene and the corresponding MSR values increased by about 25% with the presence of 0.01 M of Cd{sup 2+} or Zn{sup 2+}. Saponin is more effective in enhancing PAHs solubilization than synthetic non-ionic surfactants and has potential application in removing organic pollutants from contaminated soils. - Highlights: > The enhanced solubilization of PAHs by saponin was investigated in this study. > Saponin showed great solubilization capability for PAHs. > Saponin is more effective in enhancing HOCs solubilization at lower solution pH. > Increasing ionic strength can enhance HOCs solubilization in saponin solution. > Heavy metal ions can also enhance phenanthrene solubilization in saponin solution. - Saponin showed different solubilization properties for PAHs from the synthetic non-ionic surfactants and anionic rhamnolipid biosurfactants.

  4. Solubilization properties of polycyclic aromatic hydrocarbons by saponin, a plant-derived biosurfactant

    International Nuclear Information System (INIS)

    Zhou Wenjun; Yang Juanjuan; Lou Linjie; Zhu Lizhong

    2011-01-01

    The enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) by saponin, a plant-derived non-ionic biosurfactant, was investigated. The results indicated that the solubilization capabilities of saponin for PAHs were greater than some representative synthetic non-ionic surfactants and showed strong dependence on solution pH and ionic strength. The molar solubilization ratio (MSR) of saponin for phenanthrene was about 3-6 times of those of the synthetic non-ionic surfactants, and decreased by about 70% with the increase of solution pH from 4.0 to 8.0, but increased by approximately 1 times with NaCl concentration increased from 0.01 to 1.0 M. Heavy metal ions can enhance saponin solubilization for phenanthrene and the corresponding MSR values increased by about 25% with the presence of 0.01 M of Cd 2+ or Zn 2+ . Saponin is more effective in enhancing PAHs solubilization than synthetic non-ionic surfactants and has potential application in removing organic pollutants from contaminated soils. - Highlights: → The enhanced solubilization of PAHs by saponin was investigated in this study. → Saponin showed great solubilization capability for PAHs. → Saponin is more effective in enhancing HOCs solubilization at lower solution pH. → Increasing ionic strength can enhance HOCs solubilization in saponin solution. → Heavy metal ions can also enhance phenanthrene solubilization in saponin solution. - Saponin showed different solubilization properties for PAHs from the synthetic non-ionic surfactants and anionic rhamnolipid biosurfactants.

  5. Synthesis characterization and toxicity of lanthanide complexes with schiff bases derived from S-benzoyl dithiocarbazate and aldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqi, K S; Tabassum, S; Zaidi, S A.A.; Kureshy, R I; Khan, N H [Aligarh Muslim Univ. (India). Dept. of Chemistry

    1989-12-01

    New O:N:S and N:S donor ligands namely, S-benzoyl-N-(o-hydroxybenzaldehyde) dithiocarbazate, S-benzoyl-N-(N,N-dimethylaminobenzaldehyde ) dithiocarbazate, S-benzoyl-N(N-thiophene-2-aldehyde) dithiocarbazate and their complexes with La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III), Er(III), Yb(III), and Lu(III) have been synthesized and characterized on the basis of elemental analysis, IR, NMR and electronic spectroscopy. The nephelauxetic effect(1-{beta}overlined), bonding parameter, {beta}overlined, bsup(1/2) and Sinha covalency parameter {delta}, have been calculated. Their positive values indicate covalent nature of metal-ligand bond which is also supported by their molar conductances measured in nitrobenzene. Magnetic moment values exhibit paramagnetic nature of the complexes. Log K,{Delta}G, {Delta}H and {Delta}S values have also been ca lculated. Toxicity of the compounds has been evaluated against cockroaches and fungi(Aspergillus flavus and A. niger). The LD{sub 50} and % inhibition values demonstrate greater efficacy of the complexes than that of the free bases. (author). 4 tabs., 12 refs.

  6. Synthesis characterization and toxicity of lanthanide complexes with schiff bases derived from S-benzoyl dithiocarbazate and aldehydes

    International Nuclear Information System (INIS)

    Siddiqi, K.S.; Tabassum, S.; Zaidi, S.A.A.; Kureshy, R.I.; Khan, N.H.

    1989-01-01

    New O:N:S and N:S donor ligands namely, S-benzoyl-N-(o-hydroxybenzaldehyde) dithiocarbazate, S-benzoyl-N-(N,N-dimethylaminobenzaldehyde ) dithiocarbazate, S-benzoyl-N(N-thiophene-2-aldehyde) dithiocarbazate and their complexes with La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III), Er(III), Yb(III), and Lu(III) have been synthesized and characterized on the basis of elemental analysis, IR, NMR and electronic spectroscopy. The nephelauxetic effect(1-βoverlined), bonding parameter, βoverlined, bsup(1/2) and Sinha covalency parameter δ, have been calculated. Their positive values indicate covalent nature of metal-ligand bond which is also supported by their molar conductances measured in nitrobenzene. Magnetic moment values exhibit paramagnetic nature of the complexes. Log K,ΔG, ΔH and ΔS values have also been ca lculated. Toxicity of the compounds has been evaluated against cockroaches and fungi(Aspergillus flavus and A. niger). The LD 50 and % inhibition values demonstrate greater efficacy of the complexes than that of the free bases. (author). 4 tabs., 12 refs

  7. Solubilization of human erythrocyte membranes by ASB detergents

    Directory of Open Access Journals (Sweden)

    C.C. Domingues

    2008-09-01

    Full Text Available Understanding the membrane solubilization process and finding effective solubilizing agents are crucial challenges in biochemical research. Here we report results on the interaction of the novel linear alkylamido propyl dimethyl amino propanosulfonate detergents, ASB-14 and ASB-16, with human erythrocyte membranes. An estimation of the critical micelle concentration of these zwitterionic detergents (ASB-14 = 100 µM and ASB-16 = 10 µM was obtained using electron paramagnetic resonance. The amount of proteins and cholesterol solubilized from erythrocytes by these detergents was then determined. The hemolytic activities of the ASB detergents were assayed and the detergent/lipid molar ratios for the onset of hemolysis (Re sat and total lysis (Re sol were calculated, allowing the determination of the membrane binding constants (Kb. ASB-14 presented lower membrane affinity (Kb = 7050 M-1 than ASB-16 (Kb = 15610 M-1. The amount of proteins and cholesterol solubilized by both ASB detergents was higher while Re sat values (0.22 and 0.08 detergent/lipid for ASB-14 and ASB-16, respectively were smaller than those observed with the classic detergents CHAPS and Triton X-100. These results reveal that, besides their well-known use as membrane protein solubilizers to enhance the resolution of two dimensional electrophoresis/mass spectrometry, ASB-14 and ASB-16 are strong hemolytic agents. We propose that the physicochemical properties of ASB detergents determine their membrane disruption efficiency and can help to explain the improvement in the solubilization of membrane proteins, as reported in the literature.

  8. Mineral phosphate solubilizing bacterial community in agro-ecosystem

    African Journals Online (AJOL)

    Mineral phosphate solubilizing bacterial community in agro-ecosystem. N Saha, S Biswas. Abstract. The present communication deals with the assessment of phosphate solubilizing bacterial community structure across artificially created fertility gradient with regards to N, P and K status of soil in the experimental site.

  9. Moroccan rock phosphate solubilization during a thermo-anaerobic ...

    African Journals Online (AJOL)

    In order to investigate the presence of thermo-tolerant rock phosphate (RP) solubilizing anaerobic microbes during the fermentation process, we used grassland as sole organic substrate to evaluate the RP solubilization process under anaerobic thermophilic conditions. The result shows a significant decrease of pH from ...

  10. Copper-Catalyzed Electrophilic Amination of Organoaluminum Nucleophiles with O-Benzoyl Hydroxylamines.

    Science.gov (United States)

    Zhou, Shuangliu; Yang, Zhiyong; Chen, Xu; Li, Yimei; Zhang, Lijun; Fang, Hong; Wang, Wei; Zhu, Xiancui; Wang, Shaowu

    2015-06-19

    A copper-catalyzed electrophilic amination of aryl and heteroaryl aluminums with N,N-dialkyl-O-benzoyl hydroxylamines that affords the corresponding anilines in good yields has been developed. The catalytic reaction proceeds very smoothly under mild conditions and exhibits good substrate scope. Moreover, the developed catalytic system is also well suited for heteroaryl aluminum nucleophiles, providing facile access to heteroaryl amines.

  11. A system to analyze the complex physiological states of coal solubilizing fungi

    Energy Technology Data Exchange (ETDEWEB)

    Hoelker, U.; Moenkemann, H.; Hoefer, M. [Universitaet Bonn, Bonn (Germany). Botanisches Institut

    1997-11-01

    The mechanism by which some microorganisms solubilize brown coal is still unknown. The paper discusses the deuteromycetes Fusarium oxysporum and Trichoderma atroviride as a suitable test system to analyse the complex fungal physiology relating to coal solubilization. The two fungi can occur in two different growth substrate-controlled physiological states: a coal-solubilizing one, when cells are grown on glutamate or gluconate as substrate and a non-solubilizing one, when grown on carbohydrates. When grown on carbohydrates, F.oxysporum produces the pigment bikaverein. Purified bikaverein inhibits also coal solubilization by T. atroviride. The ability to solubilize coal is constitutive in F. oxysporum, while in T. atroviride, it has to be induced. 10 refs., 3 figs., 3 tabs.

  12. Rock phosphate solubilizing and cellulolytic actinomycete isolates of earthworm casts

    Science.gov (United States)

    Mba, Caroline C.

    1994-03-01

    Four microbial isolates, OP2, OP3, OP6, and OP7, of earthworm casts of Pontoscolex corethrurus were found to be acid tolerant actinomycetes and efficient rock phosphate (RP) solubilizers that could grow fast on NH4Cl-enriched or N-free carboxymethyl cellulose or glucose as sole carbon source. CMC (carboxymethyl cellulose) induced production of extracellular cellulase enzyme and the production of reducing sugar in all the isolates. RP solubilizing power was observed to be inversely related to glucose consumption. The most efficient RP solubilizer was found to consume the least glucose. Growth was faster on cellulose than on glucose media. N-free CMC induced greater glucose production than NH4Cl-enriched CMC medium. Both CMC and glucose media were acidified by all the isolates, however, RP solubilizing power decreased with acidification. Solubilization power was greatest with isolate OP7, which also produced the greatest amount of reducing sugar per gram CMC. Both RP solubilizing power and the cellulolytic efficiency varied among isolates. A minimum of 631 µg P/0.1 g RP and a maximum of 951.4 µg P/0.1 g RP was recorded.

  13. Copper(II)-catalyzed electrophilic amination of quinoline N-oxides with O-benzoyl hydroxylamines.

    Science.gov (United States)

    Li, Gang; Jia, Chunqi; Sun, Kai; Lv, Yunhe; Zhao, Feng; Zhou, Kexiao; Wu, Hankui

    2015-03-21

    Copper acetate-catalyzed C-H bond functionalization amination of quinoline N-oxides was achieved using O-benzoyl hydroxylamine as an electrophilic amination reagent, thereby affording the desired products in moderate to excellent yields. Electrophilic amination can also be performed in good yield on a gram scale.

  14. Thermo-tolerant phosphate-solubilizing microbes for multi-functional biofertilizer preparation.

    Science.gov (United States)

    Chang, Cheng-Hsiung; Yang, Shang-Shyng

    2009-02-01

    In order to prepare the multi-functional biofertilizer, thermo-tolerant phosphate-solubilizing microbes including bacteria, actinomycetes, and fungi were isolated from different compost plants and biofertilizers. Except Streptomycesthermophilus J57 which lacked pectinase, all isolates possessed amylase, CMCase, chitinase, pectinase, protease, lipase, and nitrogenase activities. All isolates could solubilize calcium phosphate and Israel rock phosphate; various isolates could solubilize aluminum phosphate, iron phosphate, and hydroxyapatite. During composting, biofertilizers inoculated with the tested microbes had a significantly higher temperature, ash content, pH, total nitrogen, soluble phosphorus content, and germination rate than non-inoculated biofertilizer; total organic carbon and carbon-to-nitrogen ratio showed the opposite pattern. Adding these microbes can shorten the period of maturity, improve the quality, increase the soluble phosphorus content, and enhance the populations of phosphate-solubilizing and proteolytic microbes in biofertilizers. Therefore, inoculating thermo-tolerant phosphate-solubilizing microbes into agricultural and animal wastes represents a practical strategy for preparing multi-functional biofertilizer.

  15. Solubilization of proteins: the importance of lysis buffer choice.

    Science.gov (United States)

    Peach, Mandy; Marsh, Noelle; Miskiewicz, Ewa I; MacPhee, Daniel J

    2015-01-01

    The efficient extraction of proteins of interest from cells and tissues is not always straightforward. Here we demonstrate the differences in extraction of the focal adhesion protein Kindlin-2 from choriocarcinoma cells using NP-40 and RIPA lysis buffer. Furthermore, we demonstrate the use of a more denaturing urea/thiourea lysis buffer for solubilization, by comparing its effectiveness for solubilization of small heat-shock proteins from smooth muscle with the often utilized RIPA lysis buffer. Overall, the results demonstrate the importance of establishing the optimal lysis buffer for specific protein solubilization within the experimental workflow.

  16. Application of Potential Phosphate-Solubilizing Bacteria and Organic Acids on Phosphate Solubilization from Phosphate Rock in Aerobic Rice

    Directory of Open Access Journals (Sweden)

    Qurban Ali Panhwar

    2013-01-01

    Full Text Available A study was conducted at Universiti Putra Malaysia to determine the effect of phosphate-solubilizing bacteria (PSB and organic acids (oxalic & malic on phosphate (P solubilization from phosphate rock (PR and growth of aerobic rice. Four rates of each organic acid (0, 10, 20, and 30 mM, and PSB strain (Bacillus sp. were applied to aerobic rice. Total bacterial populations, amount of P solubilization, P uptake, soil pH, and root morphology were determined. The results of the study showed significantly high P solubilization in PSB with organic acid treatments. Among the two organic acids, oxalic acid was found more effective compared to malic acid. Application of oxalic acid at 20 mM along with PSB16 significantly increased soluble soil P (28.39 mg kg−1, plant P uptake (0.78 P pot−1, and plant biomass (33.26 mg. Addition of organic acids with PSB and PR had no influence on soil pH during the planting period. A higher bacterial population was found in rhizosphere (8.78 log10 cfu g−1 compared to the nonrhizosphere and endosphere regions. The application of organic acids along with PSB enhanced soluble P in the soil solution, improved root growth, and increased plant biomass of aerobic rice seedlings without affecting soil pH.

  17. [Phosphate-solubilizing activity of aerobic methylobacteria].

    Science.gov (United States)

    Agafonova, N V; Kaparullina, E N; Doronina, N V; Trotsenko, Iu A

    2014-01-01

    Phosphate-solubilizing activity was found in 14 strains of plant-associated aerobic methylobacteria belonging to the genera Methylophilus, Methylobacillus, Methylovorus, Methylopila, Methylobacterium, Delftia, and Ancyclobacter. The growth of methylobacteria on medium with methanol as the carbon and energy source and insoluble tricalcium phosphate as the phosphorus source was accompanied by a decrease in pH due to the accumulation of up to 7 mM formic acid as a methanol oxidation intermediate and by release of 120-280 μM phosphate ions, which can be used by both bacteria and plants. Phosphate-solubilizing activity is a newly revealed role of methylobacteria in phytosymbiosis.

  18. Erythema-directed digital photography for the enhanced evaluation of topical treatments for acne vulgaris.

    Science.gov (United States)

    Micali, G; Dall'Oglio, F; Tedeschi, A; Lacarrubba, F

    2018-01-31

    Erythema-directed digital photography is a novel method for evaluating the efficacy and tolerability of topical acne treatments. Here, we describe three case reports in which erythema-directed digital photography was used to evaluate acne before and after up to 12 weeks of treatment with clindamycin 1%/tretinoin 0.025% (Clin-RA). Erythema-directed digital photography was used to evaluate acne in three patients with mild-to-moderate facial acne, two of whom had refused to continue previous topical acne treatment (benzoyl peroxide 5% and clindamycin 1%/benzoyl peroxide 5%) due to persistent irritation. Acne lesions and erythema were evaluated using standard clinical photography and erythema-directed digital photography (VISIA-CR ™ system) before and after 8-12 weeks of treatment with Clin-RA. Erythema-directed digital photography revealed background erythema from previous topical acne treatments that was not evident from standard clinical photographs and allowed a better visualization of both inflammatory and non-inflammatory lesions. In all patients, there was a clear improvement in background erythema and a reduction in acne lesions following treatment with Clin-RA. This study has demonstrated for the first time that erythema-directed digital photography can enhance the evaluation of the efficacy and tolerability of topical acne treatments. These cases show that Clin-RA was associated with improved efficacy and tolerability vs previous treatments with topical monotherapy (benzoyl peroxide 5%) or a topical fixed-dose combination (clindamycin 1%/benzoyl peroxide 5%). © 2018 The Authors. Skin Research and Technology Published by John Wiley & Sons Ltd.

  19. Effect of organic acids production and bacterial community on the possible mechanism of phosphorus solubilization during composting with enriched phosphate-solubilizing bacteria inoculation.

    Science.gov (United States)

    Wei, Yuquan; Zhao, Yue; Shi, Mingzi; Cao, Zhenyu; Lu, Qian; Yang, Tianxue; Fan, Yuying; Wei, Zimin

    2018-01-01

    Enriched phosphate-solubilizing bacteria (PSB) agent were acquired by domesticated cultivation, and inoculated into kitchen waste composting in different stages. The effect of different treatments on organic acids production, tricalcium phosphate (TCP) solubilization and their relationship with bacterial community were investigated during composting. Our results pointed out that inoculation affected pH, total acidity and the production of oxalic, lactic, citric, succinic, acetic and formic acids. We also found a strong advantage in the solubilization of TCP and phosphorus (P) availability for PSB inoculation especially in the cooling stage. Redundancy analysis and structural equation models demonstrated inoculation by different methods changed the correlation of the bacterial community composition with P fractions as well as organic acids, and strengthened the cooperative function related to P transformation among species during composting. Finally, we proposed a possible mechanism of P solubilization with enriched PSB inoculation, which was induced by bacterial community and organic acids production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. LC determination of propylene glycol in human plasma after pre-column derivatization with benzoyl chloride

    NARCIS (Netherlands)

    Sinjewel, A.; Swart, E.L.; Lingeman, H.; Wilhelm, A.J.

    2007-01-01

    A simple high-performance liquid chromatographic method, using photodiode array detection was developed for the determination of propylene glycol in human plasma and in the fluid retreived after continuous veno-venous hemofiltration. The method entailed alkaline derivatization with benzoyl chloride

  1. Prevention and Reduction of Atrophic Acne Scars with Adapalene 0.3%/Benzoyl Peroxide 2.5% Gel in Subjects with Moderate or Severe Facial Acne: Results of a 6-Month Randomized, Vehicle-Controlled Trial Using Intra-Individual Comparison.

    Science.gov (United States)

    Dréno, Brigitte; Bissonnette, Robert; Gagné-Henley, Angélique; Barankin, Benjamin; Lynde, Charles; Kerrouche, Nabil; Tan, Jerry

    2018-04-01

    Very few clinical trials have investigated the effect of topical acne treatment on scarring. Our objective was to evaluate the efficacy of adapalene 0.3%/benzoyl peroxide 2.5% gel (A0.3/BPO2.5) in atrophic acne scar formation in patients with acne. In this multicenter, randomized, investigator-blinded, vehicle-controlled study, subjects with moderate or severe facial acne (Investigator's Global Assessment [IGA] score 3 or 4; ≥ 25 inflammatory lesions; ten or more atrophic acne scars) applied A0.3/BPO2.5 or vehicle daily per half face for 24 weeks. Subjects with acne requiring systemic treatment were excluded. Assessments included investigator atrophic acne scar count, Scar Global Assessment (SGA), acne lesion count, IGA, skin roughness and skin texture, subject self-assessment of clinical acne-related scars and satisfaction questionnaire, tolerability, and safety. Included subjects (n = 67) had mainly moderate acne (92.5% IGA 3); mean scores at baseline were approximately 40 acne lesions and 12 scars per half face. By week 24, the change from baseline in total scar count was - 15.5% for A0.3/BPO2.5 versus  + 14.4% for vehicle (approximately 30% difference), with a mean of 9.5 scars versus 13.3 per half face, respectively (p vehicle (p vehicle (p vehicle side, most commonly skin irritation (14.9 vs. 6%, respectively). Topical A0.3/BPO2.5 prevented and reduced atrophic scar formation. Scar count increased with vehicle (+ 14.4%) but decreased with A0.3/BPO2.5 (- 15.5%) over 24 weeks. ClinicalTrials.gov identifier NCT02735421.

  2. Potentiality of Acidithiobacillus thiooxidans in Microbial Solubilization of Phosphate Mine Tailings

    Directory of Open Access Journals (Sweden)

    S Dhakar

    2015-04-01

    Full Text Available This paper deals with the solubilization behavior of the tailings produced by the floatation of a complex low grade phosphate ore. The composition of the tailings was essentially dolomite (52.04% with minor amounts of phosphate, iron and aluminium oxides (10.4 and 0.5% respectively. The presence of these products created uncontrolled land pollution and severely affected groundwater. An initiative has been taken up for utilization of this waste to generate an eco-friendly product. First step towards this panorama is incorporation of suitable microorganisms for the biodegradation of this effluent. Sulphur oxidizing bacteria Acidithiobacillus thiooxidans produces sulphuric acid which neutralizes the dolomitic tailings and convert it into plant available forms. The solubilization activity was tested in sulphur medium with 5, 10, 15 and 20% concentration of tailings. The solubilization is graded on the basis of pH, Electrical conductivity (EC, soluble calcium and magnesium and soluble phosphate. The results from ex-situ experiments showed that the treatment with 15% tailings ended with highest solubilization. The values of pH, EC, soluble calcium and magnesium and soluble phosphate for this treatment were 4.92, 31.6 dS/m, 10.8 mL EDTA and 17.24 µg/mL respectively. Also, the results proved that sulphur oxidizing bacteria Acidithiobacillus thiooxidans is capable of solubilizing dolomitic tailings from the Jhamarkotra mines. Finally, an important factor taken into account was solubilization of residual phosphate along with dolomite in the tailings. This combined action affects the solubilization behaviour of the residue, which was also showed successfully with the assayed laboratory studies.

  3. Bio-solubilization of Chinese lignite II: extra-cellular protein analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Xiu-xiang; Pan, Lan-ying; Shi, Kai-yi; Chen-hui; Yin, Su-dong; Luo, Zhen-fu [China University of Mining & Technology, Xuzhou (China). School of Chemical Engineering and Technology

    2009-05-15

    A white rot fungus strain, Trichoderma sp. AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization. The results showed that nitric acid pretreated Fushun lignite was solubilized by T. sp. AH and that extracellular proteins from T. sp. AH were correlated with the lignite bio-solubilization results. In the presence of Fushun lignite the extracellular protein concentration from T. sp. AH was 4.5 g/L while the concentration was 3 g/L in the absence of Fushun lignite. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the extracelular proteins detected at least four new protein bands after the T. sp. AH had solubilized the lignite. Enzyme color reactions showed that extracelular proteins from T. sp. AH mainly consisted of phenol-oxidases, but that lignin decomposition enzymes such as laccase, peroxidase and manganese peroxidases were not present. 9 refs., 8 figs.

  4. Anaerobic degradation of 2-aminobenzoic acid (anthranilic acid) via benzoyl-coenzyme A (CoA) and cyclohex-1-enecarboxyl-CoA in a denitrifying bacterium.

    Science.gov (United States)

    Lochmeyer, C; Koch, J; Fuchs, G

    1992-06-01

    The enzymes catalyzing the initial reactions in the anaerobic degradation of 2-aminobenzoic acid (anthranilic acid) were studied with a denitrifying Pseudomonas sp. anaerobically grown with 2-aminobenzoate and nitrate as the sole carbon and energy sources. Cells grown on 2-aminobenzoate are simultaneously adapted to growth with benzoate, whereas cells grown on benzoate degrade 2-aminobenzoate several times less efficiently than benzoate. Evidence for a new reductive pathway of aromatic metabolism and for four enzymes catalyzing the initial steps is presented. The organism contains 2-aminobenzoate-coenzyme A ligase (2-aminobenzoate-CoA ligase), which forms 2-aminobenzoyl-CoA. 2-Aminobenzoyl-CoA is then reductively deaminated to benzoyl-CoA by an oxygen-sensitive enzyme, 2-aminobenzoyl-CoA reductase (deaminating), which requires a low potential reductant [Ti(III)]. The specific activity is 15 nmol of 2-aminobenzoyl-CoA reduced min-1 mg-1 of protein at an optimal pH of 7. The two enzymes are induced by the substrate under anaerobic conditions only. Benzoyl-CoA is further converted in vitro by reduction with Ti(III) to six products; the same products are formed when benzoyl-CoA or 2-aminobenzoyl-CoA is incubated under reducing conditions. Two of them were identified preliminarily. One product is cyclohex-1-enecarboxyl-CoA, the other is trans-2-hydroxycyclohexane-carboxyl-CoA. The complex transformation of benzoyl-CoA is ascribed to at least two enzymes, benzoyl-CoA reductase (aromatic ring reducing) and cyclohex-1-enecarboxyl-CoA hydratase. The reduction of benzoyl-CoA to alicyclic compounds is catalyzed by extracts from cells grown anaerobically on either 2-aminobenzoate or benzoate at almost the same rate (10 to 15 nmol min-1 mg-1 of protein). In contrast, extracts from cells grown anaerobically on acetate or grown aerobically on benzoate or 2-aminobenzoate are inactive. This suggests a sequential induction of the enzymes.

  5. VIP receptors from porcine liver: High yield solubilization in a GTP-insensitive form

    International Nuclear Information System (INIS)

    Voisin, T.; Couvineau, A.; Guijarro, L.; Laburthe, M.

    1990-01-01

    Vasoactive intestinal peptide (VIP) receptors were solubilized from porcine liver membranes using CHAPS. The binding of 125 I-VIP to solubilized receptors was reversible, saturable and specific. Scatchard analysis indicated the presence of one binding site with a Kd of 6.5 ± 0.3 nM and a Bmax of 1.20 ± 0.15 pmol/mg protein. Solubilized and membrane-bound receptors displayed the same pharmacological profile since VIP and VIP-related peptides inhibited 125 I-VIP binding to both receptor preparations with the same rank order of potency e.g. VIP>helodermin>rat GRF>rat PHI>secretin>human GRF. GTP inhibited 125 I-VIP binding to membrane-bound receptors but not to solubilized receptors supporting functional uncoupling of VIP receptor and G protein during solubilization. Affinity labeling of solubilized and membrane-bound VIP receptors with 125 I-VIP revealed the presence of a single molecular component with Mr 55,000 in both cases. It is concluded that VIP receptors from porcine liver can be solubilized with a good yield, in a GTP-insensitive, G protein-free form. This represents a major advance towards the purification of VIP receptors

  6. Challenges Faced in Field Application of Phosphate-Solubilizing Bacteria

    KAUST Repository

    Eida, Abdul Aziz

    2017-08-01

    The general inaccessibility of soil phosphorous (P) to plants in combination with the depletion of global P reserves provides an incentive for researchers to find sustainable solutions to sustain food security for the ever-increasing world population. Bio-fertilizers based on bacteria and fungi able to solubilize endogenous P in soils have a high potential for increasing nutrient availability in agriculture. However, the inconsistency of bio-fertilizer performance in the field poses a major challenge for farmers. This discrepancy is thought to stem from the complexity of the interactions between crop plants, microbes, and their soil environments, as well as our lack of understanding of the processes involved. For farmers, a clear beneficial effect across different soil types, crop species, environmental conditions, and microbial communities will be required to make it worth to adopt bio-fertilizer technology based on phosphate-solubilizing microbes (PSMs). Here, we attempt to review the current knowledge of the complexity of the P-solubilization mechanisms used by PSMs and how they may be affected by interactions in the field. We also identify possible explanations for the inconsistent performance of P-solubilizing bacteria in the field and ways to solve these obstacles.

  7. Challenges Faced in Field Application of Phosphate-Solubilizing Bacteria

    KAUST Repository

    Eida, Abdul Aziz; Hirt, Heribert; Saad, Maged

    2017-01-01

    The general inaccessibility of soil phosphorous (P) to plants in combination with the depletion of global P reserves provides an incentive for researchers to find sustainable solutions to sustain food security for the ever-increasing world population. Bio-fertilizers based on bacteria and fungi able to solubilize endogenous P in soils have a high potential for increasing nutrient availability in agriculture. However, the inconsistency of bio-fertilizer performance in the field poses a major challenge for farmers. This discrepancy is thought to stem from the complexity of the interactions between crop plants, microbes, and their soil environments, as well as our lack of understanding of the processes involved. For farmers, a clear beneficial effect across different soil types, crop species, environmental conditions, and microbial communities will be required to make it worth to adopt bio-fertilizer technology based on phosphate-solubilizing microbes (PSMs). Here, we attempt to review the current knowledge of the complexity of the P-solubilization mechanisms used by PSMs and how they may be affected by interactions in the field. We also identify possible explanations for the inconsistent performance of P-solubilizing bacteria in the field and ways to solve these obstacles.

  8. Ability of m-chloroperoxybenzoic acid to induce the ornithine decarboxylase marker of skin tumor promotion and inhibition of this response by gallotannins, oligomeric proanthocyanidins, and their monomeric units in mouse epidermis in Vivo

    Science.gov (United States)

    Guilan Chen; Elisabeth M. Perchellet; Xiao Mei Gao; Steven W. Newell; richard W. Hemingway; Vittorio Bottari; Jean-Pierre Perchellet

    1995-01-01

    m-Chloroperoxybenzoic acid (CPBA) was tested for its ability to induce the ornithine decarboxylase (ODC) marker of skin tumor promotion. In contrast to benzoyl peroxide, dicumyl peroxide, and 2-butanol peroxide, 5 mg of CPBA applied twice at a 72-h interval induce ODC activity at least as much as 3 ug of 12-O-tetradecanoylphorbol-13-acetate (TPA). ODC induction peaks...

  9. Stability of solubilized benzodiazepine receptors

    NARCIS (Netherlands)

    Janssen, M.J; Ensing, K; de Zeeuw, R.A

    1997-01-01

    According to the observations of other researchers, benzodiazepine receptors solubilized with sodium deoxycholate are unstable, but stability can be improved by exchanging deoxycholate for Triton X-100. In our experiments we conclude that the choice of detergent is not the restrictive factor for the

  10. Human erythrocytes inhibit complement-mediated solubilization of immune complexes by human serum

    International Nuclear Information System (INIS)

    Dorval, B.L.

    1987-01-01

    The aim of this study was to develop an autologus human system to evaluate the effects of human erythrocytes on solubilization of immune complex precipitates (IC) by human serum. Incubation of IC with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed erythrocytes were added to human serum or guinea pig serum binding of IC to the erythrocyte occurred and IC solubilization was inhibited significantly (p <.025). Sheep erythrocytes did not bind IC or inhibit IC solubilization. To evaluate the role of human erythrocyte complement receptor (CR1) on these findings, human erythrocytes were treated with trypsin or anti-CR1 antibodies. Both treatments abrogated IC binding to human erythrocytes but did not affect the ability of the human erythrocyte to inhibit IC solubilization. Radioimmunoassay was used to measure C3, C4 and C5 activation in human serum after incubation with IC, human erythrocytes, human erythrocytes plus IC, whole blood or in whole blood plus IC

  11. Phosphate solubilization as a microbial strategy for promoting plant growth

    Directory of Open Access Journals (Sweden)

    Mayra Eleonora Beltrán Pineda

    2014-01-01

    Full Text Available Because of the constant application of chemical inputs in Agroecosystem, the cost of crop production and environmental quality of soil and water have been affected. Microorganisms carry out most biogeochemical cycles; therefore, their role is essential for agro ecosystem balance. One such functional group is the phosphate solubilizing microorganisms, which are recognized plant growth promoters. These microbial populations perform an important activity, since in many soils there are large reserves of insoluble phosphorus, as a result of fixing much of the phosphorus fertilizer applied, which cannot be assimilated by the plant. The phosphate solubilizing microorganisms use different solubilization mechanisms such as the production of organic acids, which solubilize theses insoluble phosphates in the rhizosphere region. Soluble phosphates are absorbed by the plant, which enhances their growth and productivity. By using these phosphate reserves in soils, application of chemical fertilizers is decreased, on the one hand, can again be fixed by ions Ca, Al or Fe making them insoluble and, by the other hand, increase the costs of crop production. Microbial populations have been widely studied in different types of ecosystems, both natural and Agroecosystem. Thanks to its effectiveness, in laboratory and field studies, the phosphate solubilizing phenotype is of great interest to microbial ecologists who have begun to establish the molecular basis of the traitr.

  12. Electrochemical peroxidation of PCBs and VOCs in superfund site water and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Scrudato, R.J.; Chiarenzelli, J.R. [SUNY, Oswego, NY (United States)

    1996-12-31

    An electrochemical peroxidation (ECP) process has been developed and used to degrade polychlorinated biphenyls (PCB) and volatile organic compounds (VOC)-contaminated water, sludge, and sediments at a New York State Federal and State Superfund Site. The process involves passing an oscillating low-amperage (<10 amps) current through steel electrodes immersed in an acidified water or sediment slurry into which hydrogen peroxide (<1,000 ppm) is added. The generated free radicals attack organic compounds, including organo-metallic complexes and refractory compounds including PCBs. PCB degradation ranged from about 30% to 80% in experiments involving Federal Superfund Site sediments; total PCBs were reduced by {approximately}97% to 68%, respectively, in water and slurry collected from a State Superfund subsurface storage tank. VOC bench-scale experiments involved chloroethane, 1,1-dichloroethane, dichloromethane, 1,1,1-trichloroethane, and acetone and after a 3-min ECP treatment, degradation ranged from >94% to about 99.9%. Results indicate the ECP is a viable process to degrade organic contaminants in water and sediment suspensions. Because the treated water suspensions are acidified, select trace metal sorbed to the particulates is solubilized and therefore can be segregated from the particulates, offering a process that simultaneously degrades organic contaminants and separates trace metals. 19 refs., 1 fig., 4 tabs.

  13. Biochemical solubilization of toxic salts from residual geothermal brines and waste waters

    Science.gov (United States)

    Premuzic, Eugene T.; Lin, Mow S.

    1994-11-22

    A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed, The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts, For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates.

  14. Solubilization of bovine gelatin using power ultrasound: gelation without heating.

    Science.gov (United States)

    Farahnaky, Asgar; Zendeboodi, Fatemeh; Azizi, Rezvan; Mesbahi, Gholamreza; Majzoobi, Mahsa

    2017-04-01

    The aim of this study was to investigate the efficacy of power ultrasound without using any heating stage in solubilizeing gelatin dispersions, and to characterize the mechanical and microstructural properties of the resulting gels using texture analysis and scanning electron microscopy, respectively. Usually to prepare a gel from gelatin, a primary heating stage of at about 40C or above is required to solubilize gelatin macromolecules. In this study solubilizing gelatin dispersions using power ultrasound without any heating was successfully performed. For solubilising gelatin, an ultrasound equipment with a frequency of 20 kHz, amplitude of 100% and power range of 50-150 W was used. Aqueous gelatin dispersions (4% w/v) were subjected to ultrasound for different times (40-240 s) at a constant temperature of 13C. Applying ultrasound to gelatin dispersions caused increases in water absorption and water solubility of the hydrocolloid. The textural parameters of the resulting gelatin gels, increased with increasing time and power of ultrasound. Moreover, a generalized Maxwell model with three elements was used for calculating relaxation times of the gels. The microstructural observations by SEM showed that the structural cohesiveness of the gels increased by increasing ultrasonication time. Ultrasound-assisted solubilization of gelatin can have emerging implications for industrial uses in pharmaceuticals, food and non-food systems. Usually to prepare a gel from gelatin, a primary heating stage of at about 40C or above is required to solubilize gelatin macromolecules. Therefore, the use of gelatin as a hydrocolloid in food processings or pharmaceutical formulations which lack a heating step has been a technological and practical challenge. In this study solubilizing gelatin dispersions using power ultrasound without any heating was successfully performed. Ultrasound-assisted solubilisation of gelatin can have emerging implications for industrial uses in pharmaceuticals

  15. Protein recovery from inclusion bodies of Escherichia coli using mild solubilization process.

    Science.gov (United States)

    Singh, Anupam; Upadhyay, Vaibhav; Upadhyay, Arun Kumar; Singh, Surinder Mohan; Panda, Amulya Kumar

    2015-03-25

    Formation of inclusion bodies in bacterial hosts poses a major challenge for large scale recovery of bioactive proteins. The process of obtaining bioactive protein from inclusion bodies is labor intensive and the yields of recombinant protein are often low. Here we review the developments in the field that are targeted at improving the yield, as well as quality of the recombinant protein by optimizing the individual steps of the process, especially solubilization of the inclusion bodies and refolding of the solubilized protein. Mild solubilization methods have been discussed which are based on the understanding of the fact that protein molecules in inclusion body aggregates have native-like structure. These methods solubilize the inclusion body aggregates while preserving the native-like protein structure. Subsequent protein refolding and purification results in high recovery of bioactive protein. Other parameters which influence the overall recovery of bioactive protein from inclusion bodies have also been discussed. A schematic model describing the utility of mild solubilization methods for high throughput recovery of bioactive protein has also been presented.

  16. Diversity and phosphate solubilization by bacteria isolated from Laki Island coastal ecosystem

    Directory of Open Access Journals (Sweden)

    SRI WIDAWATI

    2011-01-01

    Full Text Available Widawati S (2011 Diversity and phosphate solubilization by bacteria isolated from Laki Island coastal ecosystem. Biodiversitas 12: 17-21. Soil, water, sand, and plant rhizosphere samples collected from coastal ecosystem of Laki Island-Jakarta were screened for phosphate solubilizing bacteria (PSB. While the population was dependent on the cultivation media and the sample type, the highest bacterial population was observed in the rhizosphere of Ipomea aquatica. The PSB strains isolated from the sample registered 18.59 g-1L-1, 18.31 g-1L-1, and 5.68 g-1L-1 of calcium phosphate (Ca-P, Al-P and rock phosphate solubilization after 7-days. Phosphate solubilizing capacity was the highest in the Ca-P medium. Two strains, 13 and 14, registered highest Phosphomonoesterase activities (2.01 µgNP.g-1.h-1 and 1.85NP µg.g-1.h-1 were identified as Serattia marcescens, and Pseudomonas fluorescense, respectively. Both strains were isolated from the crops of Amaranthus hybridus and I. aquatica, respectively, which are commonly observed in coastal ecosystems. The presence of phosphate solubilizing microorganisms and their ability to solubilize various types of phosphate species are indicative of the important role of both species of bacteria in the biogeochemical cycle of phosphorus and the plant growth in coastal ecosystems.

  17. FORMULA ESTABLISHMENT OF COLORLESS Pb(II COMPLEX WITH N-BENZOYL-N-PHENYL HYDROXYLAMINE (BPA USING ATOMIC ABSORPTION SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Dhananjay B Sarode

    2012-02-01

    Full Text Available A new method for determination of stoichiometry of colorless complexes by using atomic absorption spectrophotometric technique in continuous variation method and slope ratio method was described here. This method can be used in same manner as that of mole ratio method and slope ratio method. In this method atomic absorption spectroscopy was used instead of UV-Vis spectrophotometry. Atomic absorption spectrophotometric technique is superior to UV-Vis spectrophotometry as it can be applied to colorless soluble complexes. Pb(II and n-benzoyl-n-phenyl hydroxylamine react to form colorless complex at pH 6.5, which can be easily determined by this method. It was found that Pb(II forms 1:2 complex with n-benzoyl-n-phenyl hydroxylamine and is quantitatively extracted back to aqueous solution for AAS analysis.

  18. Plutonium recovery from incinerator ash and centrifuge sludge by peroxide fusion

    International Nuclear Information System (INIS)

    Partridge, J.A.; Wheelwright, E.J.

    1975-05-01

    A technique was demonstrated for solubilizing the plutonium contained in incinerator ash and in other waste solids (such as solids accumulated by centrifugation after solvent extraction contacts in the plutonium reclamation facility at Hanford). A sodium hydroxide--sodium peroxide fusion is performed on the Pu-containing solids. The cooled melt is then dissolved in dilute nitric acid. Mild steel cans were used as ''single use'' crucibles for the fusions. Both the can and the cooled melt are dissolved in nitric acid. Fusion tests were conducted on three different cans of incinerator ash and on one can of centrifuge sludge. The series of tests demonstrated that a caustic-peroxide fusion treatment can yield 95 percent or greater recovery of plutonium from these waste solids. In most cases, quantitative recovery of the plutonium can probably be achieved by recycling the residual solids obtained in aqueous dissolution of the cooled fusion mixture. Tests with some of the incinerator ash and with the centrifuge sludge resulted in gelatinous precipitates which were difficult to separate from the nitric acid dissolver solutions. These gelatinous precipitates present what is probably the major problem to be overcome in the use of this Pu recovery method. Techniques need to be examined for making these residual solids less difficult to separate from the dissolver solution. (U.S.)

  19. Differential Precipitation and Solubilization of Proteins.

    Science.gov (United States)

    Ryan, Barry J; Kinsella, Gemma K

    2017-01-01

    Differential protein precipitation is a rapid and economical step in protein purification and is based on exploiting the inherent physicochemical properties of the polypeptide. Precipitation of recombinant proteins, lysed from the host cell, is commonly used to concentrate the protein of choice before further polishing steps with more selective purification columns (e.g., His-Tag, Size Exclusion, etc.). Recombinant proteins can also precipitate naturally as inclusion bodies due to various influences during overexpression in the host cell. Although this phenomenon permits easier initial separation from native proteins, these inclusion bodies must carefully be differentially solubilized so as to reform functional, correctly folded proteins. Here, appropriate bioinformatics tools to aid in understanding a protein's propensity to aggregate and solubilize are explored as a backdrop for a typical protein extraction, precipitation, and selective resolubilization procedure, based on a recombinantly expressed protein.

  20. Extractive properties of benzohydroxamic and N-benzoyl-benzohydroxamic acids as analytical reagents towards six transition metal ions

    International Nuclear Information System (INIS)

    Mohamed, Mohamed Rafie Hamid

    1999-06-01

    Two hydroxamic acids were prepared: benzohydroxamic and N-benzoyl benzohydroxamic acids. The former was prepared by coupling the free hydrox amine with benzoyl chloride with the ratio 1:1 in alkaline medium, where as the latter by the same procedure with the ratio 1:2 respectively, they were identified by their melting points, elemental analysis of their nitrogen contents. infra-red spectrophotometry, as well as their nitrogen using elevation of boiling point and the titration method to determine their molecular weights. The two hydroxamic acids were used as analytical reagents for the extraction of the metals Cr(vi), Fe(III), Ti(iv), Co(II) and U(vi). Benzohydroxamic acid has a maximum extraction 99.55% for Cr.(vi) 3M H 2 SO 4 , of 90.16% for Ti(iv) at pH 2.0,of 80.56% for Co(II) at pH 8.0 and 98.01% for U(vi) at pH 6.0. N-benzoyl benzohydroxamic acid has a maximum extraction of 96.45% for Cr(vi) at 3M H 2 So 4 , of 90.82% for Fe(III) at pH 4.0, of 97.02% for V(v) at 3M H 2 So 4 , of 83.56% for Ti(iv) at pH 2.0, of 89.82% for Co(II) at pH 8.0 and of 97.16% for U(vi) at pH 6.0. at the same pH of maximum extraction using heavy matrix, synthetic sea-water, benzohydroxamic acid has maximum values of 91.08%, of 77.99%, of 91.39%, of 87.50 and of 93.17% for Cr(vi), Fe(III), V(v), Ti(iv), Co9II) and U(vi) respectively whereas n-benzoyl benzohydroxamic acid has maximum values of 86.17%, of 77.78%, of 89.61%, of 75.66%, of 79.63% and of 91.18% for Cr(vi), Fe(III), V(v), Ti(iv), Co(II) and U(vi) respectively. The ratio of metal to ligand was determined utilizing the continuous variation method. It was 1 :2, 1: 1, 1 : 1, 1 : 2, 1: 2 and 1 : 2 with respect to Cr(vi), fe(III), Ti(iv), Co(II) and U(vi) respectively.(Author)

  1. An application of micelle solubilization spectrophotometry in the determination of thorium

    International Nuclear Information System (INIS)

    Peng Changhai; Zeng Xiaoming

    1988-01-01

    In this review article the characteristics of the analytical method of Th by means of micelle solubilization spectrophotometry are described and the mechanism of the solubilization and chemical reactions involved is discussed. Also the various color-developing reagents that have been used for this determination are described and compared

  2. Structural, antimicrobial and computational characterization of 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea.

    Science.gov (United States)

    Atiş, Murat; Karipcin, Fatma; Sarıboğa, Bahtiyar; Taş, Murat; Çelik, Hasan

    2012-12-01

    A new thiourea derivative, 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea (bcht) has been synthesized from the reaction of 2-amino-4-chlorophenol with benzoyl isothiocyanate. The title compound has been characterized by elemental analyses, FT-IR, (13)C, (1)H NMR spectroscopy and the single crystal X-ray diffraction analysis. The structure of bcht derived from X-ray diffraction of a single crystal has been presented. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method using 6-311++G(d,p) basis set. The complete assignments of all vibrational modes were performed on the basis of the total energy distributions (TED). Isotropic chemical shifts ((13)C NMR and (1)H NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. Theoretical calculations of bond parameters, harmonic vibration frequencies and nuclear magnetic resonance are in good agreement with experimental results. The UV absorption spectra of the compound that dissolved in ACN and MeOH were recorded. Bcht was also screened for antimicrobial activity against pathogenic bacteria and fungi. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Effect of acid and alkaline solubilization on the properties of surimi based film

    Directory of Open Access Journals (Sweden)

    Thummanoon Prodpran

    2005-05-01

    Full Text Available The effect of acid and alkaline solubilizing processes on the properties of the protein based film from threadfin bream surimi was investigated. Surimi films prepared from both processes had the similar light transmission, tensile strength (TS and elongation at break (EAB (P<0.05. However, film with alkaline process had slightly lower water vapor permeability (WVP, compared to that prepared by acid solubilizing process. The protein concentration in the film-forming solution directly affected the properties of the film. Increase in protein concentration resulted in an increase in TS, EAB as well as WVP. The film prepared by acid solubilizing process had an increase in yellowish color as evidenced by the continuous increase in b* and E* values during the storage at r oom temperature. The acid and alkali solubilizing processes caused the degradation of muscle protein in surimi, especially with increasing exposure time. Therefore, solubilizing process had the influence on the properties of the protein film from threadfin bream surimi.

  4. Solubilization of human cells by the styrene-maleic acid copolymer: Insights from fluorescence microscopy.

    Science.gov (United States)

    Dörr, Jonas M; van Coevorden-Hameete, Marleen H; Hoogenraad, Casper C; Killian, J Antoinette

    2017-11-01

    Extracting membrane proteins from biological membranes by styrene-maleic acid copolymers (SMAs) in the form of nanodiscs has developed into a powerful tool in membrane research. However, the mode of action of membrane (protein) solubilization in a cellular context is still poorly understood and potential specificity for cellular compartments has not been investigated. Here, we use fluorescence microscopy to visualize the process of SMA solubilization of human cells, exemplified by the immortalized human HeLa cell line. Using fluorescent protein fusion constructs that mark distinct subcellular compartments, we found that SMA solubilizes membranes in a concentration-dependent multi-stage process. While all major intracellular compartments were affected without a strong preference, plasma membrane solubilization was found to be generally slower than the solubilization of organelle membranes. Interestingly, some plasma membrane-localized proteins were more resistant against solubilization than others, which might be explained by their presence in specific membrane domains with differing properties. Our results support the general applicability of SMA for the isolation of membrane proteins from different types of (sub)cellular membranes. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Isolation of phosphatase-producing phosphate solubilizing bacteria from Loriya hot spring: Investigation of phosphate solubilizing in the presence of different parameters

    Directory of Open Access Journals (Sweden)

    Maryam Parhamfar

    2014-04-01

    Full Text Available Introduction: Biofertilizers are the microorganisms that can convert useless nutrient to usable compounds. Unlike fertilizer, cost of biofertilizer production is low and doesn’t produce ecosystem pollution. Phosphate fertilizers can be replaced by phosphate biofertilizer to produce improvement. So, it is necessary to screen the climate-compatible phosphate solubilizing bacteria. Materials and methods: In this project samples were picked up from Loriya hot spring, which are located in Jiroft. Samples were incubated in PKV medium for 3 days. Screening of phosphate solubilizing bacteria was performed on the specific media, based on clear area diameter. The best bacterium was identified based on 16s rDNA gene. Phosphate solubilizing activity of this strain was considered in different carbon, nitrogen, phosphate and pH sources. Results: Sequence alignment and phylogenetic tree results show that B. sp. LOR033 is closely related to Bacillus licheniformis, with 97% homology. In addition, results show that maximum enzyme production was performed after 2 days that incubation pH was decreased simultaneously when the time was increased. Carbon sources investigation show that glucose is the most appropriate in enzyme production and phosphate releasing. Furthermore, results show that the optimum initial pH for phytase production was pH5.0. Different phosphate sources show that tricalcium phosphate has the suitable effect on enzyme activity in three days of incubation. Discussion and conclusion: Phosphatase enzyme production capacity, growth in acidic pH and phosphate solubilizing potential in different salt and phosphate sources show that this strain has considerable importance as biofertilizers.

  6. [Solubilization Specificities Interferon beta-1b from Inclusion Bodies].

    Science.gov (United States)

    Zhuravko, A S; Kononova, N V; Bobruskin, A I

    2015-01-01

    A new solubilization method of recombinant interferon beta-1b (IFNβ-1b) from the inclusion bodies was developed. This method allows to extract the target protein selectively in the solutions of different alcohols, such as ethanol, propanol and isopropanol. It was shown that the more effective IFNβ-1b solubilization was achieved in the 55% propanol solution. This method allowed to extract the target protein from inclusion bodies around 85-90%, and significantly reduced Escherichia coli content in the solubilizate, in comparison with standard methods.

  7. Mechanisms of coal solubilization by the deuteromycetes Trichoderma atroviride and Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Hoelker, U.; Ludwig, S.; Scheel, T.; Hoefer, M. [Bonn Univ. (Germany). Botanisches Inst. und Botanischer Garten

    1999-07-01

    Three different mechanisms can be envisaged that are used by fungi to solubilize coal: the production of alkaline substances, the extrusion of chelators and, of special interest in the scope of biotechnology, the action of enzymes. Whether these mechanisms are operating separately or in various combinations has not yet been finally assessed. The two deuteromycetes Fusarium oxysporum and Trichoderma atroviride solubilize coal by synergistic effects of various different mechanisms depending on the cell metabolism. F. oxysporum seems to solubilize coal by increasing the pH of the mycelial surroundings and by the action of chelators induced during growth in glutamate-containing media (without involvement of enzymes). T. atroviride, on the other hand, appears to use, in addition to an alkaline pH and a high chelator activity, at least two classes of enzyme activity to attack coal: hydrolytic activity for coal solubilization and ligninolytic activity for degradation of humic acids. (orig.)

  8. Occurrence and functioning of phosphate solubilizing ...

    African Journals Online (AJOL)

    Occurrence and functioning of phosphate solubilizing microorganisms from oil palm tree ( Elaeis guineensis ) rhizosphere in Cameroon. ... While the use of soluble mineral phosphate fertilizers is the obvious best means to combat phosphate ... in order to improve agricultural production, using low inputs technology. Isolates ...

  9. Zinc solubilizing Bacillus spp. potential candidates for biofortification in maize.

    Science.gov (United States)

    Mumtaz, Muhammad Zahid; Ahmad, Maqshoof; Jamil, Moazzam; Hussain, Tanveer

    2017-09-01

    Bioaugmentation of Zn solubilizing rhizobacteria could be a sustainable intervention to increase bioavailability of Zn in soil which can be helpful in mitigation of yield loss and malnutrition of zinc. In present study, a number of pure rhizobacterial colonies were isolated from maize rhizosphere and screened for their ability to solubilize zinc oxide. These isolates were screened on the basis of zinc and phosphate solubilization, IAA production, protease production, catalase activity and starch hydrolysis. All the selected isolates were also positive for oxidase activity (except ZM22), HCN production (except ZM27) and utilization of citrate. More than 70% of isolates produces ammonia, hydrogen cyanide, siderophores, exopolysaccharides and cellulase. More than half of isolates also showed potential for urease activity and production of lipase. The ZM31 and S10 were the only isolates which showed the chitinase activity. All these isolates were evaluated in a jar trial for their ability to promote growth of maize under axenic conditions. Results revealed that inoculation of selected zinc solubilizing rhizobacterial isolates improved the growth of maize. In comparison, isolates ZM20, ZM31, ZM63 and S10 were best compared to other tested isolates in stimulating the growth attributes of maize like shoot length, root length, plant fresh and dry biomass. These strains were identified as Bacillus sp. (ZM20), Bacillus aryabhattai (ZM31 and S10) and Bacillus subtilis (ZM63) through 16S rRNA sequencing. This study indicated that inoculation of Zn solubilizing strains have potential to promote growth and can be the potential bio-inoculants for biofortification of maize to overcome the problems of malnutrition. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Distribution of phosphate solubilizer fungi on soil microhabitats in two landscapes from Guaviare, Colombia

    Directory of Open Access Journals (Sweden)

    Diana Fernanda Vera

    2002-01-01

    Full Text Available The distribution of the phosphate solubilizer mycobiota in two different soil microhabitats present in Guaviare, Colombia, were studied. Twelve samples from Arazá rhizosphere (Eugenia stipitata McVaugh and from soil without roots were processed using the soil wahing method (Domsch  et al., 1980. The percentage of colonization of soil particles by fungi was 69 %, with a higher intensity of colonization coming from the rhizospheric microhabitat. The high percentage of potential solubilizer colonies may point to this type of soil as reserve pf solubilizer fungi. The rhizospheric effect has been the main factor involved in the composition of the solubilizer fungi community.

  11. Solubilization of Polycyclic Aromatic Hydrocarbons by Single and Binary Mixed Rhamnolipid-Sophorolipid Biosurfactants.

    Science.gov (United States)

    Song, Dandan; Liang, Shengkang; Yan, Lele; Shang, Yujun; Wang, Xiuli

    2016-07-01

    Biosurfactants are promising additives for surfactant enhanced remediation (SER) technologies due to their low toxicity and high biodegradability. To develop green and efficient additives for SER, the aqueous solubility enhancements of polycyclic aromatic hydrocarbons (PAHs; naphthalene, phenanthrene, and pyrene) by rhamnolipid (RL) and sophorolipid (SL) biosurfactants were investigated in single and binary mixed systems. The solubilization capacities were quantified in terms of the solubility enhancement factor, molar solubilization ratio (MSR), and micelle-water partition coefficient (). Rughbin's model was applied to evaluate the interaction parameters (β) in the mixed RL-SL micelles. The solubility of the PAHs increased linearly with the glycolipid concentration above the critical micelle concentration (CMC) in both single and mixed systems. Binary RL-SL mixtures exhibited greater solubilization than individual glycolipids. At a SL molar fraction of 0.7 to 0.8, the solubilization capacity was the greatest, and the MSR and reached their maximum values, and β values became positive. These results suggest that the two biosurfactants act synergistically to increase the solubility of the PAHs. The solubilization capacity of the RL-SL mixtures increased with increasing temperature and decreased with increasing salinity. The aqueous solubility of phenanthrene reached a maximum value at pH of 5.5. Moreover, the mixed RL-SL systems exhibited a strong ability to solubilize PAHs, even in the presence of heavy metal ions. These mixed biosurfactant systems have the potential to improve the performance of SER technologies using biosurfactants to solubilize hydrophobic organic contaminants by decreasing the applied biosurfactant concentration, which reduces the costs of remediation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Microbial Phosphorus Solubilization and Its Potential for Use in Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Elizabeth T. Alori

    2017-06-01

    Full Text Available The use of excess conventional Phosphorus (P fertilizers to improve agricultural productivity, in order to meet constantly increasing global food demand, potentially causes surface and ground water pollution, waterway eutrophication, soil fertility depletion, and accumulation of toxic elements such as high concentration of selenium (Se, arsenic (As in the soil. Quite a number of soil microorganisms are capable of solubilizing/mineralizing insoluble soil phosphate to release soluble P and making it available to plants. These microorganisms improve the growth and yield of a wide variety of crops. Thus, inoculating seeds/crops/soil with Phosphate Solubilizing Microorganisms (PSM is a promising strategy to improve world food production without causing any environmental hazard. Despite their great significance in soil fertility improvement, phosphorus-solubilizing microorganisms have yet to replace conventional chemical fertilizers in commercial agriculture. A better understanding of recent developments in PSM functional diversity, colonizing ability, mode of actions and judicious application should facilitate their use as reliable components of sustainable agricultural systems. In this review, we discussed various soil microorganisms that have the ability to solubilize phosphorus and hence have the potential to be used as bio fertilizers. The mechanisms of inorganic phosphate solubilization by PSM and the mechanisms of organic phosphorus mineralization are highlighted together with some factors that determine the success of this technology. Finally we provide some indications that the use of PSM will promote sustainable agriculture and conclude that this technology is ready for commercial exploitation in various regions worldwide.

  13. Solubilization and characterization of a novel tyrosine kinase from rat adipocytes

    International Nuclear Information System (INIS)

    Yagaloff, K.A.; Czech, M.P.

    1987-01-01

    The authors report the efficient solubilization and characterization of a Triton X-100 insoluble tyrosine kinase from rat adipocytes. Plasma membranes were prepared from rat epididymal fat pads and were solubilized in 1% Triton X-100. Following centrifugation, the pellet was solubilized for 15 min at 4 0 C using both ionic and non-ionic detergents. Tyrosine kinase activity was measured in the soluble and particulate fractions using the exogenous substrate poly(glu-tyr) in a TCA precipitation assay. Reactions were performed in 50mM Hepes, 10mM MgCl 2 and 100μM gamma[ 32 P]-ATP (10Ci/mmol) at 4 0 C with or without 1mg/ml of the polyaminoacid. Incorporation rates of 100 to 1000 pmol/min/mg were obtained, while endogenous [ 32 P] incorporation was typically less than 10% of that in the presence of poly(glu-tyr). More than 75% of the tyrosine kinase activity was recovered in the soluble supernatant using this assay methodology. The solubilized tyrosine kinase was found to require Mg 2+ or Mn 2+ but preferred Mg 2+ and was inhibited by high levels of Mn 2+ . Kinase activity was strongly inhibited by Ca 2+ (>50% at 1mM), NaCl (>50% at 250mM) and NH 4 SO 4 (>50% at 50mM) but was activated by 10μM heparin and 5mM dithiothreitol. These properties distinguish the solubilized tyrosine kinase from other cellular tyrosine kinases

  14. Crude oil degradation by phosphate-solubilizing bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, M.J.B.D.; Nair, S.; David, J.J.; Chandramohan, D.

    Phosphate-solubilizing bacteria were isolated from tropical areas around the Indian peninsula. Two of the isolates showed high phosphatase activity. The isolates were identified as Klebsiella pneumoniae and Bacillus pumilus, and they showed high...

  15. Exploring the Arabidopsis Proteome: Influence of Protein Solubilization Buffers on Proteome Coverage

    KAUST Repository

    Marondedze, Claudius; Wong, Aloysius Tze; Groen, Arnoud; Serano, Natalia Lorena Gorron; Jankovic, Boris R.; Lilley, Kathryn; Gehring, Christoph A; Thomas, Ludivine

    2014-01-01

    The study of proteomes provides new insights into stimulus-specific responses of protein synthesis and turnover, and the role of post-translational modifications at the systems level. Due to the diverse chemical nature of proteins and shortcomings in the analytical techniques used in their study, only a partial display of the proteome is achieved in any study, and this holds particularly true for plant proteomes. Here we show that different solubilization and separation methods have profound effects on the resulting proteome. In particular, we observed that the type of detergents employed in the solubilization buffer preferentially enriches proteins in different functional categories. These include proteins with a role in signaling, transport, response to temperature stimuli and metabolism. This data may offer a functional bias on comparative analysis studies. In order to obtain a broader coverage, we propose a two-step solubilization protocol with first a detergent-free buffer and then a second step utilizing a combination of two detergents to solubilize proteins.

  16. Exploring the Arabidopsis Proteome: Influence of Protein Solubilization Buffers on Proteome Coverage

    Directory of Open Access Journals (Sweden)

    Claudius Marondedze

    2014-12-01

    Full Text Available The study of proteomes provides new insights into stimulus-specific responses of protein synthesis and turnover, and the role of post-translational modifications at the systems level. Due to the diverse chemical nature of proteins and shortcomings in the analytical techniques used in their study, only a partial display of the proteome is achieved in any study, and this holds particularly true for plant proteomes. Here we show that different solubilization and separation methods have profound effects on the resulting proteome. In particular, we observed that the type of detergents employed in the solubilization buffer preferentially enriches proteins in different functional categories. These include proteins with a role in signaling, transport, response to temperature stimuli and metabolism. This data may offer a functional bias on comparative analysis studies. In order to obtain a broader coverage, we propose a two-step solubilization protocol with first a detergent-free buffer and then a second step utilizing a combination of two detergents to solubilize proteins.

  17. Exploring the Arabidopsis Proteome: Influence of Protein Solubilization Buffers on Proteome Coverage

    KAUST Repository

    Marondedze, Claudius

    2014-12-31

    The study of proteomes provides new insights into stimulus-specific responses of protein synthesis and turnover, and the role of post-translational modifications at the systems level. Due to the diverse chemical nature of proteins and shortcomings in the analytical techniques used in their study, only a partial display of the proteome is achieved in any study, and this holds particularly true for plant proteomes. Here we show that different solubilization and separation methods have profound effects on the resulting proteome. In particular, we observed that the type of detergents employed in the solubilization buffer preferentially enriches proteins in different functional categories. These include proteins with a role in signaling, transport, response to temperature stimuli and metabolism. This data may offer a functional bias on comparative analysis studies. In order to obtain a broader coverage, we propose a two-step solubilization protocol with first a detergent-free buffer and then a second step utilizing a combination of two detergents to solubilize proteins.

  18. Characterization of solubilized human and rat brain US -endorphin-receptor complex

    Energy Technology Data Exchange (ETDEWEB)

    Helmeste, D.M.; Li, C.H.

    1986-01-01

    Opioid receptors have been solubilized from human striatal and rat whole-brain membranes by use of 3-((3-cholamidopropyl)dimethylammonio)-1-propanesulfonate (CHAPS). Tritiated human US -endorphin (TH-US /sub h/-EP) binding revealed high-affinity competition by morphine, naloxone, and various US -EP analogues. Lack of high-affinity competition by (+/-)-3,4-dichloro-N-methyl-N-(2-(1-pyrrolidinyl)cyclohexyl)benzeneacetamide methanesulfonate (U50-488, Upjohn) indicated that k sites were not labeled by TH-US -/sub h/-EP under these conditions. Affinities were similar in both soluble and membrane preparations except for (Met)enkephalin, which appears to be rapidly degraded by the solubilized extract. Size differences between human and rat solubilized TH-US /sub h/-EP-receptor complexes were revealed by exclusion chromatography.

  19. Fixed-Dose Combination Gel of Adapalene and Benzoyl Peroxide plus Doxycycline 100 mg versus Oral Isotretinoin for the Treatment of Severe Acne: Efficacy and Cost Analysis.

    Science.gov (United States)

    Penna, Pete; Meckfessel, Matthew H; Preston, Norman

    2014-01-01

    Acne vulgaris is a chronic skin disease with a high prevalence. Left untreated or inadequately treated, acne vulgaris can lead to psychological and physical scarring, as well as to unnecessary medical expenses. Oral isotretinoin is an effective treatment for severe resistant nodular and conglobate acne vulgaris. A regimen consisting of a fixed-dose combination of adapalene and benzoyl peroxide gel, 0.1%/2.5% (A-BPO) with oral doxycycline 100 mg (A-BPO/D) has been demonstrated to be efficacious and well tolerated in patients with severe acne and may be an alternative to oral isotretinoin for some patients with severe acne. The objective of this analysis was to compare the relative efficacy and associated costs of A-BPO/D versus oral isotretinoin. In this analysis, comparisons of relative efficacy were made using previously published studies involving similar patient populations with severe acne that warrant the use of oral isotretinoin. The pricing for oral doxycycline and oral isotretinoin was estimated based on the maximum allowable cost from 9 states, and the pricing for A-BPO was calculated as the range between the average wholesale price and the wholesale acquisition cost. For this analysis, 2 treatment models were generated to compare costs: (1) a basic treatment model that examined the costs of an initial regimen of either A-BPO/D or oral isotretinoin without considering probable outcomes, and (2) a long-term model that factored in likely treatment outcomes and subsequent treatments into associated costs. The basic treatment model assumed that patients would be prescribed a single regimen of A-BPO/D for 12 weeks or oral isotretinoin for 20 weeks. The long-term model considered the probability of each treatment successfully managing patients' acne, as well as likely additional regimens of A-BPO monotherapy or an additional regimen of oral isotretinoin. As a result of different treatment durations, the costs for each treatment were normalized to weekly cost of

  20. Solubilization of plutonium hydrous oxide by iron-reducing bacteria

    International Nuclear Information System (INIS)

    Rusin, P.A.; Quintana, L.; Brainard, J.R.; Strietelmeler, B.A.; Tait, C.D.; Ekberg, S.A.; Palmer, P.D.; Newton, T.W.; Clark, D.L.

    1994-01-01

    The removal of plutonium from soils id challenging because of its strong sorption to soils and limited solubility, Microbial reduction of metals is known to affect the speciation and solubility of sparingly soluble metals in the environment, notably iron and manganese. The similarity in reduction potential for α-FeOOH(s) and hydrous PuO 2 (s) suggests that iron-reducing bacteria may also reduce and solubilize plutonium. Bacillus strains were used to demonstrate that iron-reducing bacteria mediate the solubilization of hydrous PuO 2 (s) under anaerobic conditions. Up to ∼90% of the PuO 2 was biosolubilized in the presence of nitrilotriacetic acid (NTA) within 6-7 days. Biosolubilization occurred to a lesser extent (∼ 40%) in the absence of NTA. Little PuO 2 solubilization occurred in sterile culture media or in the presence of a non-iron-reducing Escherichia coli. These observations suggest a potentially attractive, environmentally benign strategy for the remediation of Pu-contaminated soils. 26 refs., 5 figs., 2 tabs

  1. EVALUATION OF PHOSPHATE SOLUBILIZING MICROORGANISMS (PSMs FROM RHIZOSPHERE SOIL OF DIFFERENT CROP PLANTS AND ITS ANTAGONISTIC ACTIVITY

    Directory of Open Access Journals (Sweden)

    Samikan Krishnakumar

    2014-04-01

    Full Text Available Indigenous rhizosphere soil samples were collected during study period (October 2011 – March 2012 of different crop plant from Thiruvannamalai District, Tamilnadu, India for the enumeration of Phosphate solubilizing microorganisms (PSMs. Efficient phosphate solubilizing bacteria, fungi and heterotrophic bacteria were enumerated. Maximum heterotrophic bacterial populations (19.4 X105, phosphate solubilizing bacteria (4.7 X 105 were recorded in the month of February and phosphate solubilizing fungi (3.9 X 102 were documented in the month of December in rhizosphere soil of ground nut. Minimum bacterial populations (14.3 X 105 were observed in rhizosphere soil of chilli in the month of March. Lowest phosphate solubilizing bacteria (1.2 X105 and phosphate solubilzing fungi (1.2 X 102 were observed in rhizosphere soil of paddy during the month of October. Phosphate solubilizing bacteria Pseudomonassp. - BS1, Bacillus sp. – BS2, Micrococcus sp. – BS3 and fungi Aspergillus sp. – FS1, Penicillium sp. – FS2.and Trichoderma sp. – FS3 were identified. Pseudomonas sp. - BS1. exhibited maximum solubilizing efficiency (SE and solubilizing index (SI of 300.0 and 4.0 respectively. In fungi Aspergillus sp. – FS1 showed a maximum solubilizing efficiency (SE and solubilizing index(SI of 283.3 and 3.8 respectively. Antagonistic activity of P-solubilizing Pseudomonassp. - BS1 was deliberated against selected fungal plant pathogens. Among pathogens studied Aspergillus sp. showed a maximum inhibition activity (16 mm and minimum activity (12 mm was observed against Fusarium sp. Moreover inhibition efficiency (IE and inhibition index (II of Pseudomonas sp. - BS1. also calculated base on the antagonistic activity. Aspergillus sp. exhibited highest inhibition efficiency and inhibition index of 166.6 and 3.6 respectively.

  2. Synthesis of benzoyl-mercaptoacetylglycylglycylglycine C6H5COSCH2CO(NHCH2CO)3OH (Bz-MAG3)

    International Nuclear Information System (INIS)

    Al-Ktaifani, M.; Nakawa, M. A.; Nahmo, A.; Allaf, W.

    2006-11-01

    Benzo-mercaptoacetylglycylglcylglycine (Bz-MAG3) was prepared by three subsequent steps starting from benzoyl chloride. The obtained product was fully characterized by its multi-nuclear NMR and IR spectroscopy. The purity of the product was confirmed by HPLC. (author)

  3. Molecular identification of phosphate solubilizing bacterium ...

    African Journals Online (AJOL)

    A phosphate solubilizing bacterium was isolated from the rhizosphere soil of upland rice and identified by 16S rRNA gene sequencing. The gene sequence showed 99% homology with Alcaligenes faecalis. Based on the gene sequence homology, it was identified as A. faecalis. Interaction effect of this bacterium on growth ...

  4. Nitrolysis of the CN Single Bond and Related Chemistry of Nitro and Nitroso Groups.

    Science.gov (United States)

    1988-03-01

    oxime of be 4,5-diphenyl-l-triphenylmethoxy-l,23- triazole (11). It was benzoyl cyanide (Scheme 6), for which radical intermediates hydrolysed by...S-Pnitroxide (a radical scavenger) or benzoyl peroxide (a radical *PhC CCN)- NO2 Ag PhCON--CPh suc)I I source). A partial extension of the overall...two anomethylenenitronate anion. (Attempts to prepare the pathways for fragmentation of the ester (3) (C,.H,0 N.O,): one ketenimine (15) by a

  5. Evaluation of pink-pigmented facultative methylotrophic bacteria for phosphate solubilization.

    Science.gov (United States)

    Jayashree, Shanmugam; Vadivukkarasi, Ponnusamy; Anand, Kirupanithi; Kato, Yuko; Seshadri, Sundaram

    2011-08-01

    Thirteen pink-pigmented facultative methylotrophic (PPFM) strains isolated from Adyar and Cooum rivers in Chennai and forest soil samples in Tamil Nadu, India, along with Methylobacterium extorquens, M. organophilum, M. gregans, and M. komagatae were screened for phosphate solubilization in plates. P-solubilization index of the PPFMs grown on NBRIP-BPB plates for 7 days ranged from 1.1 to 2.7. The growth of PPFMs in tricalcium phosphate amended media was found directly proportional to the glucose concentration. Higher phosphate solubilization was observed in four strains MSF 32 (415 mg l(-l)), MDW 80 (301 mg l(-l)), M. komagatae (279 mg l(-l)), and MSF 34 (202 mg l(-l)), after 7 days of incubation. A drop in the media pH from 6.6 to 3.4 was associated with an increase in titratable acidity. Acid phosphatase activity was more pronounced in the culture filtrate than alkaline phosphatase activity. Adherence of phosphate to densely grown bacterial surface was observed under scanning electron microscope after 7-day-old cultures. Biochemical characterization and screening for methanol dehydrogenase gene (mxaF) confirmed the strains as methylotrophs. The mxaF gene sequence from MSF 32 clustered towards M. lusitanum sp. with 99% similarity. This study forms the first detailed report on phosphate solubilization by the PPFMs.

  6. Rock phosphate solubilization by the ectomycorrhizal fungus ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... phosphate solubilization is accompanied by acid production. Thus, the evidence ..... of organic acids. (Khan et al., 2010) such as acetate, lactate, oxalate, ... (2014) also observed that oxalic acid was secreted by L. fraterna to ...

  7. Management strategies for acne vulgaris

    Directory of Open Access Journals (Sweden)

    Whitney KM

    2011-04-01

    Full Text Available Kristen M Whitney1, Chérie M Ditre21Philadelphia College of Osteopathic Medicine, Philadelphia, PA, USA; 2Skin Enhancement Center and Cosmetic Dermatology, Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, PA, USADate of preparation: 30th November 2010Conflicts of interest: None declaredClinical question: What are the most effective treatment(s for mild, moderate, severe, and hormonally driven acne?Results: Mild acne responds favorably to topical treatments such as benzoyl peroxide, salicylic acid, and a low-dose retinoid. Moderate acne responds well to combination therapy comprising-topical benzoyl peroxide, antibiotics, and/or retinoids, as well as oral antibiotics in refractory cases and oral contraceptive pills for female acne patients. Severe nodulocystic acne vulgaris responds best to oral isotretinoin therapy. In female patients with moderate to severe acne, facial hair, loss of scalp hair and irregular periods, polycystic ovarian syndrome should be considered and appropriate treatment with hormonal modulation given. Adjunctive procedures can also be considered for all acne patients.Implementation: Pitfalls to avoid when treating acne: treatment of acne in women of childbearing age; familiarization of all acne treatments in order to individualize management for patients; indications for specialist referral.Keywords: acne vulgaris, benzoyl peroxide, retinoids, antibiotics, light and laser therapy, photodynamic therapy, photopneumatic therapy, chemical peels

  8. Synthesis and Biological Activity of Novel Amino Acid-(N'-Benzoyl Hydrazide and Amino Acid-(N'-Nicotinoyl Hydrazide Derivatives

    Directory of Open Access Journals (Sweden)

    Sherine N. Khattab

    2005-09-01

    Full Text Available The coupling reaction of benzoic acid and nicotinic acid hydrazides with N- protected L-amino acids including valine, leucine, phenylalanine, glutamic acid and tyrosine is reported. The target compounds, N-Boc-amino acid-(N`-benzoyl- and N- Boc-amino acid-(N`-nicotinoyl hydrazides 5a-5e and 6a-6e were prepared in very high yields and purity using N-[(dimethylamino-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl- methylene]-N-methyl-methanaminium hexafluorophosphate N-oxide (HATU as coupling reagent. The antimicrobial activity of the Cu and Cd complexes of the designed compounds was tested. The products were deprotected affording the corresponding amino acid-(N`-benzoyl hydrazide hydrochloride salts (7a-7e and amino acid-(N`- nicotinoyl hydrazide hydrochloride salts (8a-8e. These compounds and their Cu and Cd complexes were also tested for their antimicrobial activity. Several compounds showed comparable activity to that of ampicillin against S. aureus and E. coli.

  9. Dopamine transporter; solubilization and characterization of [3H] GBR-12935 binding in canine caudate

    International Nuclear Information System (INIS)

    Sallee, F.R.

    1988-01-01

    The dopamine (DA) transporter protein, as indexed by [ 3 H]GBR-12935 binding, was solubilized from canine striatal membranes with the detergent digitonin. This solubilized protein retained the same pharmacological characteristics as membrane attached uptake sites. The binding of [ 3 H]GBR-12935 to solubilized preparations was specific, saturable and reversible with an equilibrium dissociation constant of approximately 3 nM and a maximum ligand binding (B max ) of 3.4 pmol/mg protein. [ 3 H]GBR-12935 also bound to solubilized sites in a sodium-independent manner with a K D of approximately 6 nM and a B max of 1.2 ± 0.2 pmol/mg protein. Dopamine uptake inhibitors and substrates of DA uptake inhibited [ 3 H]GBR-12935 binding in a stereoselective and concentration dependent manner. For these compounds rank order of potency for inhibition of [ 3 H]GBR-12935 binding correlated with their potency for inhibition of dopamine uptake. K D values for DA uptake inhibitors in solubilized preparations correlated with those obtained on [ 3 H]GBR-12935 binding in the native state. The dopamine transporter appears to be a transmembrane glycoprotein by virtue of its absorption and specific elution from wheat germ agglutinin (WGA)-lectin column. Solubilization of the putative dopamine transporter with full retention of binding activity now allows for the purification and biochemical characterization of this important membrane protein

  10. Isolation of phosphate solubilizer fungi from Araza rhizosphere

    Directory of Open Access Journals (Sweden)

    Diana Fernanda Vera

    2002-01-01

    Full Text Available Araza is an eatable plant, original from the Amazon region which has been describedas a promising species for commercialization (Quevedo 1995. This plant has highproductivity even in low content phosphate soil but the presence of phosphatesolubilizazing microorganisms may contribute to increase this element availability.In this study we report the isolation and characterization of solubilizing fungiprocessed using the soil washing method, from soil samples were Araza is cultivated attwo regions in Guaviare, Colombia. Eighteen isolates of fungi capable of solubilizingphosphate were obtained from 2 different sources. The most importat species that solubilized phosphate from calcium were Trichodermaaureoviride, Aspergillus aculeatus,Trichodermastrain 1 y Trichodermastrain 2 and for phosphate from iron: Aspergillus oryzae,Paecilomycesstrain 3, Gongronella butleri& Fusarium oxysporum

  11. Complement-mediated solubilization of immune complexes and their interaction with complement C3 receptors

    DEFF Research Database (Denmark)

    Petersen, Ivan; Baatrup, Gunnar; Jepsen, H H

    1985-01-01

    Some of the molecular events in the complement (C)-mediated solubilization of immune complexes (IC) have been clarified in recent years. The solubilization is primarily mediated by alternative C pathway proteins whereas factors in the classical pathway accelerate the process. Components of the me......Some of the molecular events in the complement (C)-mediated solubilization of immune complexes (IC) have been clarified in recent years. The solubilization is primarily mediated by alternative C pathway proteins whereas factors in the classical pathway accelerate the process. Components...... of the cellular localization, expression and structure of the C3 receptors, especially the C3b (CR1) receptor, has been considerably extended in the last few years, whereas our understanding of the physiological role of these receptors is still fragmentary. However, it is becoming increasingly evident...

  12. Optimization of Liquid Medium for High Phosphate Solubilization by Serratia Marcescens Strain AGKT4

    Directory of Open Access Journals (Sweden)

    Mohd Yusoff Abd. Samad

    2017-12-01

    Full Text Available This study is on the optimization of the medium for solubilization of phosphate based on the Box-Behnken design and response surface methodology. Optimization of the liquid medium for phosphate solubilization using Serratia marcescens strain AGKT4 was carried out by varying the concentrations of 3 ingredients; the fructose, peptone and inoculum size of bacteria. A mathematical model derived from the response surface methodology was then validated statistically for the target test variables. The highest phosphate solubilization in the medium was achieved at the optimal concentrations of fructose and peptone at 6% (w/v and 0.6% (w/v, respectively. The maximum phosphate solubilization at these concentrations was 239.12 µg/mL. Under the same conditions, the bacterial growth in the medium was 9 log10 CFU.

  13. Phosphate solubilization and multiple plant growth promoting ...

    African Journals Online (AJOL)

    Phosphate solubilizing efficiencies of the strains were analyzed using different insoluble phosphorus sources and the results show that most isolates released a substantial amount of soluble phosphate from tricalcium phosphate, rock phosphate and bone meal. Screening for multiple plant growth promoting attributes ...

  14. Isolation and characterization of phosphate-solubilizing bacteria ...

    African Journals Online (AJOL)

    ... in nitrogen, free semi-solid medium and able to produce siderophore. PSB inoculants with their beneficial traits would be considered as potential biofertilizer for the sustainable aerobic rice cultivation system. Key words: Aerobic rice, antagonistic effect, indoleacetic acid, organic acids, phosphorus solubilizing bacteria.

  15. Isolation and Characterization of Efficient Phosphate Solubilizing ...

    African Journals Online (AJOL)

    Vostro154032bit

    ABSTRACT. Applications of biofertilizer have great practical importance for increasing fertility of the soil and reducing environmental pollution. Screening and characterizing phosphate solubilizing Bacillus. (PSB) strains from different agroecologies of Tigray soil and in vitro assessment for the adaptability under different ...

  16. Isolation and characterization of efficient Phosphate Solubilizing ...

    African Journals Online (AJOL)

    Applications of biofertilizer have great practical importance for increasing fertility of the soil and reducing environmental pollution. Screening and characterizing phosphate solubilizing Bacillus (PSB) strains from different agroecologies of Tigray soil and in vitro assessment for the adaptability under different abiotic stress ...

  17. Production of uranium peroxide

    International Nuclear Information System (INIS)

    Caropreso, F.E.; Kreuz, D.F.

    1977-01-01

    A process is claimed of recovering uranium values as uranium peroxide from an aqueous uranyl solution containing dissolved vanadium and sodium impurities by treating the uranyl solution with hydrogen peroxide in an amount sufficient to have an excess of at least 0.5 parts H 2 O 2 per part of vanadium (V 2 O 5 ) above the stoichiometric amount required to form the uranium peroxide, the hydrogen peroxide treatment is carried out in three sequential phases consisting of I, a precipitation phase in which the hydrogen peroxide is added to the uranyl solution to precipitate the uranium peroxide and the pH of the reaction medium maintained in the range of 2.5 to 5.5 for a period of from about 1 to 60 minutes after the hydrogen peroxide addition; II, a digestion phase in which the pH of the reaction medium is maintained in the range of 3.0 to 7.0 for a period of about 5 to 180 minutes and III, a final phase in which the pH of the reaction medium is maintained in the range of 4.0 to 7.0 for a period of about 1 to 60 minutes during which time the uranium peroxide is separated from the reaction solution containing the dissolved vanadium and sodium impurities. The excess hydrogen peroxide is maintained during the entire treatment up until the uranium peroxide is separated from the reaction medium

  18. Marine actinobacteria showing phosphate-solubilizing efficiency in Chorao Island, Goa, India

    Digital Repository Service at National Institute of Oceanography (India)

    Dastager, S.G.; Damare, S.R.

    . 2005, Isolation and characterization of phosphate solubilizing bacteria from the rhizosphere of crop plants of Korea. Soil Biology & Biochemistry. 37, 1970–1974. 6. Collins C.H., Lyne P.M., 1980, Microbiological methods. London: Butterworth and Co..., Studies on phosphobacteriain Cochin Backwater. J. Mar. Biolog Associ. India. 29, 297–305. 21. Ramachandran K., Srinivasan V., Hamza S., Anandaraj M., 2007, Phosphate solubilizing bacteria isolated from the rhizosphere soil and its growth promotion...

  19. Synthesis and luminescence properties of novel 4-(N-carbazole methyl) benzoyl hydrazone Schiff bases

    International Nuclear Information System (INIS)

    Guo Dongcai; Wu Panliang; Tan Hui; Xia Long; Zhou Wenhui

    2011-01-01

    4-(N-carbazole methyl) benzoyl hydrazine was synthesized on the basis of carbazole, and then nine novel carbazolyl acylhydrazone Schiff bases were synthesized by the condensation reaction between 4-(N-carbazole methyl) benzoyl hydrazine and the substituted benzaldehydes. The relationships between the substituted group types and the UV fluorescence spectral properties, as well as the fluorescence quantum yields of the title Schiff bases were also investigated. The results show that the introduction of both the donating and accepting electron groups causes various grade redshifts of the fluorescence characteristic emission peak of the title Schiff bases to occur.The fluorescence quantum yields of the title Schiff bases with the donating group are increased, and the highest fluorescence quantum yield is up to 0.703. - Highlights: → Nine novel Schiff bases have been designed and synthesized. → Introduction of the donating electron groups causes various grade red shifts of the fluorescence characteristic emission peak and the UV characteristic absorption peak of the synthesized Schiff bases. → Introduction of the donating electron groups causes the fluorescence quantum yields to be increased considerably. →Introduction of the accepting electron groups causes the fluorescence intensity and quantum yield of the synthesized Schiff bases to be reduced. → Fluorescence quantum yield of o-hydroxyl-substituted Schiff base is up to 0.703; this Schiff base is expected to be used as hole transport optical material.

  20. Chelating agents improve enzymatic solubilization of pectinaceous co-processing streams

    DEFF Research Database (Denmark)

    Ravn, Helle Christine; Meyer, Anne S.

    2014-01-01

    of different levels of ethylene-diaminetetraacetic acid (EDTA), citric acid, oxalic acid, and phosphate was assessed in relation to enzymatic solubilization of isopropanol precipitatable oligo- and polysaccharides from sugar beet pulp, citrus peel, and two types of potato pulp. The two types of potato pulp...... solubilization yields. The effect of the chelating agents correlated to their dissociation constants (pKa values) and calcium binding constants and citric acid and EDTA exerted highest effects. Maximum polysaccharide yield was obtained for FiberBind 400 where the enzymatic treatment in presence of citric acid...

  1. Hydrogen peroxide safety issues

    International Nuclear Information System (INIS)

    Conner, W.V.

    1993-01-01

    A literature survey was conducted to review the safety issues involved in handling hydrogen peroxide solutions. Most of the information found in the literature is not directly applicable to conditions at the Rocky Flats Plant, but one report describes experimental work conducted previously at Rocky Flats to determine decomposition reaction-rate constants for hydrogen peroxide solutions. Data from this report were used to calculate decomposition half-life times for hydrogen peroxide in solutions containing several decomposition catalysts. The information developed from this survey indicates that hydrogen peroxide will undergo both homogeneous and heterogeneous decomposition. The rate of decomposition is affected by temperature and the presence of catalytic agents. Decomposition of hydrogen peroxide is catalyzed by alkalies, strong acids, platinum group and transition metals, and dissolved salts of transition metals. Depending upon conditions, the consequence of a hydrogen peroxide decomposition can range from slow evolution of oxygen gas to a vapor, phase detonation of hydrogen peroxide vapors

  2. Consortium inoculum of five thermo-tolerant phosphate solubilizing Actinomycetes for multipurpose biofertilizer preparation.

    Science.gov (United States)

    Nandimath, Arusha P; Karad, Dilip D; Gupta, Shantikumar G; Kharat, Arun S

    2017-10-01

    Alkaline pH of the soil facilitates the conversion of phosphate present in phosphate fertilizer applied in the field to insoluble phosphate which is not available to plants. Problem of soluble phosphate deficiency arises, primarily due to needless use of phosphate fertilizer. We sought to biofertilizer with the thermo-tolerant phosphate solubilizing actinomycetes consortium that could convert insoluble phosphate to soluble phosphate at wider temperature range. In the present investigation consortium of five thermo-tolerant phosphate solubilizing actinomycetes was applied for preparation of inoculum to produce multipurpose bio-fertilizer. Phosphates solubilizing thermo-tolerant 32 actinomycetes strains were processed for identification with the use of PIBWIN software and were screened for phosphate solubilizing activity. Amongst these five actinomycetes were selected on the basis of their ability to produce cellulase, chitinase, pectinase, protease, lipase, amylase and phosphate solubilizing enzymes. Ability to produce these enzymes at 28°C and 50°C were examined. Biofertilizer was prepared by using agricultural waste as a raw material. While preparation of bio-fertilizer the pH decreased from 7.5 to 4.3 and temperature increased up to 74°C maximum at the end of 4 th week and in subsequent week it started to decline gradually till it reached around 50°C, which was found to be stable up to eighth week. This thermo-tolerant actinomycetes consortium released soluble phosphate of up to 46.7 μg ml -1 . As the mesophilic organisms die out at high temperature of composting hence thormo-tolerant actinomycetes would be the better substitute for preparation of phosphate solubilizing bio-fertilizer with added potential to degrade complex macromolecules in composting.

  3. Studying furosemide solubilization using an in vitro model simulating gastrointestinal digestion and drug solubilization in neonates and young infants

    DEFF Research Database (Denmark)

    Klitgaard, Mette; Sassene, Philip Jonas; Selen, Arzu

    2017-01-01

    -2months). METHODS: The utilized in vitro model was designed to mimic the digestion and drug solubilization processes occurring in the stomach, and the small intestine of the neonate and young infant population, using physiologically relevant media, volumes and digestive enzymes. Overall the experimental...

  4. Evaluation methods used for phosphate-solubilizing bacteria ...

    African Journals Online (AJOL)

    This work aimed to evaluate the different selection methods and select inorganic phosphorus-solubilizing bacteria as potential plant-growth promoters. Bacterial isolates obtained from sugarcane roots and soil were tested using solid growth media containing bicalcium phosphate and Irecê Apatite ground rock phosphate as ...

  5. Microbial efficacy of phosphate solubilization in agro-saline soils of various areas of sindh region

    International Nuclear Information System (INIS)

    Noor, A.A.; Shah, F.A.

    2013-01-01

    Microorganisms are the most prominent entities for solubilization of phosphate in various soils of different areas of Sindh Province including Tando Muhammad Khan, Tando Allah Yar, Nawabshah, Rato Dero-Larkana, Shikarpur and Umer Kot. These soils, having varying concentrations of chemicals, different climatic conditions, pH and varying numbers of microorganisms for PSA (Phosphate Solubilization Activity). This presentation shows the isolation of different fungi and bacteria capable Psa including fungi (Fusarium sp. Aspergillus sp. Penicillium sp. and Rhizopus sp.) and bacteria (Bacillus sp. Pseudomonas sp. and Arthrobacter sp.). From the observations, it was revealed that fungi Aspergillus sp. and Bacillus sp. showed greater phosphate solubilization activity as compared to other fungi and bacteria showing 60 and 53.33% Psa (Phosphate Solubilizing Activity) respectively. (author)

  6. Isolation of Indigenous Bacteria of Phosphate Solubilizing from Green Bean Rhizospheres

    Directory of Open Access Journals (Sweden)

    N Arfarita

    2017-04-01

    Full Text Available The use of phosphate-solubilizing bacteria (PSB as a biological fertilizer of Agricultural land is one solution to overcome problem of phosphate availability for plants. However, often application of a biological fertilizer is ineffective for certain places. The purpose of this study was to obtain indigenous phosphate solubilizing bacterial isolates that can be effective in the area of Malang. Samples were collected from rhizosphereof green bean plants at three locations in Malang, East Java. The study was conducted to determine the total bacterial population of soil samples, to select the best three bacterial isolates in phosphate solubilizing ability, which is not antagonistic and nonpathogenic for plants,along with observing its potential as a bacterial consortium. The highest total population was found in FHR samples of 1.5x1011 CFU / mL. We have selected three bacterial isolates namely SPP1, SPP2 and SPP3. They were not antagonistic to each other and nonpathogenic on mungbean sprouts. They had possibility of producing growth hormone which characterized by an increasing in length of plant and total root length, be compared to controls. Strain SPP2 has shown the highest activity of phosphate solubilization then was selected for 16S rRNA identification. Similarity test of genome sequence of strain SPP2 had 99% similarity with Pseudomonas plecoglossicida strain PR19

  7. Identification of Minor Benzoylated 4-Phenylcoumarins from a Mammea neurophylla Bark Extract

    Directory of Open Access Journals (Sweden)

    Bach Tai Dang

    2015-09-01

    Full Text Available Through dereplication analysis, seven known Mammea coumarins were identified in a fraction obtained from Mammea neurophylla dichloromethane bark extract selected for its ability to prevent advanced glycation end-product (AGE formation. Among them, a careful examination of the NMR dataset of pedilanthocoumarin B led to a structural revision. Inspection of LC-DAD-MSn chromatograms allowed us to predict the presence of four new compounds, which were further isolated. Using spectroscopic methods (1H-, 13C- and 2D-NMR, HRMS, UV, these compounds were identified as new benzoyl substituted 4-phenylcoumarins (iso-pedilanthocoumarin B and neurophyllol C and 4-(1-acetoxypropylcoumarins cyclo F (ochrocarpins H and I.

  8. Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

    Directory of Open Access Journals (Sweden)

    Lílian Estrela Borges Baldotto

    2014-06-01

    Full Text Available Besides fixing N2, some diazotrophic bacteria or diazotrophs, also synthesize organic acids and are able to solubilize rock phosphates, increasing the availability of P for plants. The application of these bacteria to pineapple leaf axils in combination with rock phosphate could increase N and P availability for the crop, due to the bacterial activity of biological nitrogen fixation and phosphate solubilization. The objectives of this study were: (i to select and characterize diazotrophs able to solubilize phosphates in vitro and (ii evaluate the initial performance of the pineapple cultivars Imperial and Pérola in response to inoculation with selected bacteria in combination with rock phosphate. The experiments were conducted at Universidade Estadual do Norte Fluminense Darcy Ribeiro, in 2009. In the treatments with bacteria the leaf contents of N, P and K were higher than those of the controls, followed by an increase in plant growth. These results indicate that the combined application of diazotrophic phosphate-solubilizing bacteria Burkholderia together with Araxá rock phosphate can be used to improve the initial performance of pineapple slips.

  9. Effect of hydrostatic pressure on gas solubilization in micelles.

    Science.gov (United States)

    Meng, Bin; Ashbaugh, Henry S

    2015-03-24

    Molecular dynamics simulations of anionic sodium decylsulfate and nonionic pentaethylene glycol monodecyl ether micelles in water have been performed to examine the impact of hydrostatic pressure on argon solubilization as a function of pressure. The potential-of-mean force between the micelles and argon demonstrates that nonpolar gases are attracted to the interiors of both micelles. The affinity of argon for micelle interiors, however, decreases with increasing pressure as a result of the comparatively higher molar volume of argon inside assemblies. We evaluate solubility enhancement coefficients, which describe the drop in the solute chemical potential as a function of the micellized surfactant concentration, to quantify the impact of micellization on gas solubilization. While argon is similarly attracted to the hydrophobic cores of both micelles, the gas is more effectively sequestered within nonionic micelles compared with anionic micelles as a result of salting out by charged head groups and accompanying counterions. The solubility enhancement coefficients of both micelles decrease with increasing pressure, reflecting the changing forces observed in the potentials-of-mean force. An analytical liquid drop model is proposed to describe the pressure dependence of argon solubilization within micelles that captures the simulation solubility enhancement coefficients after fitting an effective micelle radius for each surfactant.

  10. Gadolinium (III) 2-benzoyl-1,1,3,3-tetracyanopropenide diacetate. Synthesis and crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Karpov, Sergey V.; Kayukov, Yakov S.; Grigor' ev, Arthur A. [Department of Chemistry and Pharmaceutics, I.N. Ul' yanov Chuvash State University, Cheboksary (Russian Federation); Tafeenko, Victor A. [Department of Chemistry, Lomonosov Moscow State University (Russian Federation)

    2018-02-15

    2-Acyl-1,1,3,3-tetracyanopropenides (ATCN) is a stable organic salts, containing the carbonyl group in addition to the tetracyanoallyl (TCA) fragment in the anion. TCA anions are known as bridging ligands with variable denticity with potential application in organic electronics and as a ionic liquids components. In this communication we reporting the synthesis and crystal structure of gadolinium(III) 2-benzoyl-1,1,3,3-tetracyanopropenide diacetate - the first lanthanide ATCN. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Lanthanum benzoyl acetonates: an IR and mass spectrometric study of the composition and structure

    International Nuclear Information System (INIS)

    Kostyuk, N.N.; Dik, T.A.; Tereshko, N.V.

    2005-01-01

    IR spectroscopy and mass spectrometry were used to study the structure of lanthanum chelates of benzoyl acetone (1-phenyl-1,3-butadione, HBA) of the following compositions: La(BA) 3 · EtOH, La(BA) 2 , La(BA) 2 · CH 3 CN, and La(BA) 2 · HDA, where EtOH = ethanol, HDA = nonadecanoic acid. It is demonstrated that a quasi-aromatic metalloring is formed in lanthanum chelates studied. Stable metal-containing fragments of the molecular ions of lanthanum bis- and tris-benzoylacetonate were identified [ru

  12. Recovery of plutonium from oxalate supernatant using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

    International Nuclear Information System (INIS)

    Mohapatra, P.K.; Manchanda, V.K.; Gupta, K.K.; Singh, R.K.

    1997-01-01

    Extraction of Pu(IV) from oxalate supernatant was carried out employing varying concentrations of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP). Near quantitative extraction of Pu(IV) from an aqueous solution of 0.2M oxalic acid and 3M HNO 3 was possible employing 0.05M PMBP solution in xylene. Extraction studies at different uranium loading conditions were carried out and conditions for quantitative stripping were arrived at. (author). 2 refs., 4 tabs

  13. Interaction of complement-solubilized immune complexes with CR1 receptors on human erythrocytes. The binding reaction

    DEFF Research Database (Denmark)

    Jepsen, H H; Svehag, S E; Jarlbaek, L

    1986-01-01

    showed no binding. IC solubilized in 50% human serum in the presence of autologous RBC bound rapidly to RBC-CR1, with maximal binding within less than 1 min at 37 degrees C. Release of CR1-bound IC under these conditions occurred slowly, requiring more than 30 min. Only binding of 'partially' solubilized...... of an intact classical pathway in preparing the IC for binding to RBC-CR1. C-solubilized IC could be absorbed to solid-phase conglutinin or antibody to C3c and C4c, and these ligands were able to inhibit the binding of solubilized IC to RBC. Heparin also exerted a marked, dose-dependent inhibitory effect...

  14. Contribution to the study of the chemical effects of the (n, γ) reaction on copper N-benzoyl N-phenyl hydroxylaminate and copper N-benzoyl N-(o) Tolyl hydroxylaminate

    International Nuclear Information System (INIS)

    Nakanishi, C.

    1987-01-01

    The influence of some factors such as pre-heating and pre-irradiation with gamma rays on the retention and thermal annealing of copper N-benzoyl N-phenyl hydroxylaminate and of copper N-benzolyl N-(o) tolyl hydroxylaminate is studied. The complexes were synthesized and characterized by determination of the melting-point, elemental analysis, X-ray diffraction, infra-red and visible range absoption spectrometry-thermogravimetric analysis were examined and the stability of the compounds was checked against heating and gamma irradiation from a 60 Co source. Some experiments using the Szilard-Chalmers effect were carried out by irradiating the compound in the IEA-R 1 nuclear reactor and calculating its specific activities. (M.J.C.) [pt

  15. Phosphate solubilizing bacteria and alkaline phosphatase activity in coastal waters off Trivandrum

    Digital Repository Service at National Institute of Oceanography (India)

    Mamatha, S.S.; Gobika, A.; Janani, P.

    , Korea. Marine Pollution Bulletin. 62. pp. 2476–2482. 98 Journal of Coastal Environment Illmer, P. and Schinner, F. 1995. Solubilization of inorganic calcium phosphates solubilization mechanisms. Soil Biology and Biochemistry. 27. pp. 57...-solubilising microorganisms associated with the rhizosphere of mangroves in a semiarid coastal lagoon. Biology and Fertility of Soils. 30. 460-468. Wurl, O. 2009. Practical guidelines for the analysis of sea water. CRC Press, Boca Raton. pp. 143-178. Zohary, T...

  16. Peroxide organometallic compounds and their transformations

    International Nuclear Information System (INIS)

    Razuvaev, G.A.; Brilkina, T.G.

    1976-01-01

    A survey is given experimental works on synthesis and reactions of peroxide organometallic compounds. Reactions have been considered of organometallic compounds with oxygen and organic peroxides which result in formation of both peroxide and non-peroxide products. Possible routes and mechanisms of chemical transformations of peroxide organometallic compounds have been discussed. Reactions of organometallic compounds with oxygen and peroxides have been considered

  17. Safe handling of potential peroxide forming compounds and their corresponding peroxide yielded derivatives.

    Energy Technology Data Exchange (ETDEWEB)

    Sears, Jeremiah Matthew; Boyle, Timothy J.; Dean, Christopher J.

    2013-06-01

    This report addresses recent developments concerning the identification and handling of potential peroxide forming (PPF) and peroxide yielded derivative (PYD) chemicals. PPF chemicals are described in terms of labeling, shelf lives, and safe handling requirements as required at SNL. The general peroxide chemistry concerning formation, prevention, and identification is cursorily presented to give some perspective to the generation of peroxides. The procedure for determining peroxide concentrations and the proper disposal methods established by the Hazardous Waste Handling Facility are also provided. Techniques such as neutralization and dilution are provided for the safe handling of any PYD chemicals to allow for safe handling. The appendices are a collection of all available SNL documentation pertaining to PPF/PYD chemicals to serve as a single reference.

  18. Isolation and Characterization of Efficient Phosphate Solubilizing ...

    African Journals Online (AJOL)

    Vostro154032bit

    Research Article http://dx.doi.org/10.4314/mejs.v9i2.9. Momona Ethiopian Journal of Science (MEJS), V9(2):262-273,2017 ©CNCS, Mekelle University, ISSN:2220-184X. Isolation and Characterization of Efficient Phosphate Solubilizing Bacillus (PSB) from Different Agro-ecological Zones of Tigray Soil, Ethiopia. Kibrom, F.G.

  19. Mild-temperature thermochemical pretreatment of green macroalgal biomass: Effects on solubilization, methanation, and microbial community structure.

    Science.gov (United States)

    Jung, Heejung; Baek, Gahyun; Kim, Jaai; Shin, Seung Gu; Lee, Changsoo

    2016-01-01

    The effects of mild-temperature thermochemical pretreatments with HCl or NaOH on the solubilization and biomethanation of Ulva biomass were assessed. Within the explored region (0-0.2M HCl/NaOH, 60-90°C), both methods were effective for solubilization (about 2-fold increase in the proportion of soluble organics), particularly under high-temperature and high-chemical-dose conditions. However, increased solubilization was not translated into enhanced biogas production for both methods. Response surface analysis statistically revealed that HCl or NaOH addition enhances the solubilization degree while adversely affects the methanation. The thermal-only treatment at the upper-limit temperature (90°C) was estimated to maximize the biogas production for both methods, suggesting limited potential of HCl/NaOH treatment for enhanced Ulva biomethanation. Compared to HCl, NaOH had much stronger positive and negative effects on the solubilization and methanation, respectively. Methanosaeta was likely the dominant methanogen group in all trials. Bacterial community structure varied among the trials according primarily to HCl/NaOH addition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Solubilization of diabase and phonolite dust by filamentous fungus

    Directory of Open Access Journals (Sweden)

    Juliana Andréia Vrba Brandão

    2014-10-01

    Full Text Available The objective of this study was to evaluate the effect of the fungus Aspergillus niger strain CCT4355 in the release of nutrients contained in two types of rock powder (diabase and phonolite by means of in vitro solubilization trials. The experimental design was completely randomized in a 5 x 4 factorial design with three replications. It was evaluated five treatments (phonolite dust + culture medium; phonolite dust + fungus + culture medium; diabase powder + culture medium; diabase powder + fungus + culture medium and fungus + culture medium and four sampling dates (0, 10, 20 and 30 days. Rock dust (0.4% w/v was added to 125 mL Erlenmeyer flasks containing 50 mL of liquid culture medium adapted to A. niger. The flasks were incubated at 30°C for 30 days, and analysis of pH (in water, titratable acidity, and concentrations of soluble potassium, calcium, magnesium, zinc, iron and manganese were made. The fungus A. niger was able to produce organic acids that solubilized ions. This result indicates its potential to alter minerals contained in rock dust, with the ability to interact in different ways with the nutrients. A significant increase in the amount of K was found in the treatment with phonolite dust in the presence of the fungus. The strain CCT4355 of A. niger can solubilize minerals contained in these rocks dust.

  1. High pH solubilization and chromatography-based renaturation and purification of recombinant human granulocyte colony-stimulating factor from inclusion bodies.

    Science.gov (United States)

    Li, Ming; Fan, Hua; Liu, Jiahua; Wang, Minhong; Wang, Lili; Wang, Chaozhan

    2012-03-01

    Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is a very efficient therapeutic protein drug which has been widely used in human clinics to treat cancer patients suffering from chemotherapy-induced neutropenia. In this study, rhG-CSF was solubilized from inclusion bodies by using a high-pH solution containing low concentration of urea. It was found that solubilization of the rhG-CSF inclusion bodies greatly depended on the buffer pH employed; alkalic pH significantly favored the solubilization. In addition, when small amount of urea was added to the solution at high pH, the solubilization was further enhanced. After solubilization, the rhG-CSF was renatured with simultaneous purification by using weak anion exchange, strong anion exchange, and hydrophobic interaction chromatography, separately. The results indicated that the rhG-CSF solubilized by the high-pH solution containing low concentration of urea had much higher mass recovery than the one solubilized by 8 M urea when using anyone of the three refolding methods employed in this work. In the case of weak anion exchange chromatography, the high pH solubilized rhG-CSF could get a mass recovery of 73%. The strategy of combining solubilization of inclusion bodies at high pH with refolding of protein using liquid chromatography may become a routine method for protein production from inclusion bodies.

  2. Mineral phosphate solubilization by wild type and radiation induced mutants of pantoea dispersa and pantoea terrae

    International Nuclear Information System (INIS)

    Murugesan, Senthilkumar; Lee, Young Keun; Kim, Jung Hun

    2009-01-01

    Three mineral phosphate solubilizing (MPS) bacteria where isolated from rhizosphere soil samples of common bean and weed plants. 16S rDNA analysis indicated that the isolate P2 and P3 are closely related to Pantoea dispersa while isolate P4 is closely related to Pantoea terrae. Islates P2 and P3 recorded 381.60 μg ml -1 of tricalcium phosphate (TCP) solubilization respectively on 3 days incubation. Isolate P4 recorded the TCP solubilization of 215.85 μg ml -1 and the pH was dropped to 4.44 on 24 h incubation. Further incubation of P4 sharply decreased the available phosphorous to 28.94 μg ml -1 and pH level was raised to 6.32. Gamma radiation induced mutagenesis was carried out at LD 99 dose of the wild type strains. The total of 14 mutant clones with enhanced MPS activity and 4 clones with decreased activity were selected based on solubilization index (SI) and phosphate solubilization assay. Mutant P2-M1 recorded the highest P-solubilizing potential among any other wild or mutnat clones by releasing 504.21 μg ml -1 of phosphorous i.e. 35% higher than its wild type by the end of day 5. A comparative evaluation of TCP solubilization by wild type isolates of Pantoea and their mutants, led to select three MPS mutant clones such as P2-M1, P3-M2 and P3-M4 with a potential to release >471.67 μg ml 1 of phosphorous from TCP. These over expressing mutant clones are considered as suitable candidates for biofertilization

  3. 21 CFR 172.802 - Acetone peroxides.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acetone peroxides. 172.802 Section 172.802 Food and... Multipurpose Additives § 172.802 Acetone peroxides. The food additive acetone peroxides may be safely used in... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide...

  4. β-Cyclodextrin-dextran polymers for the solubilization of poorly soluble drugs.

    Science.gov (United States)

    di Cagno, Massimiliano; Terndrup Nielsen, Thorbjørn; Lambertsen Larsen, Kim; Kuntsche, Judith; Bauer-Brandl, Annette

    2014-07-01

    The aim of this study was to assess the potential of novel β-cyclodextrin (βCD)-dextran polymers for drug delivery. The size distribution of βCD-dextrans (for eventual parenteral administration), the influence of the dextran backbones on the stability of the βCD/drug complex, the solubilization efficiency of poorly soluble drugs and drug release properties were investigated. Size analysis of different βCD-dextrans was measured by size exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AF4). Stability of drug/βCD-dextrans was assessed by isothermal titration calorimetry (ITC) and molar enthalpies of complexation and equilibrium constants compared to some commercially available βCD derivatives. For evaluation of the solubilization efficiency, phase-solubility diagrams were made employing hydrocortisone (HC) as a model of poorly soluble drugs, whereas reverse dialysis was used to detect potential drug supersaturation (increased molecularly dissolved drug concentration) as well as controlled release effects. Results indicate that all investigated βCD-polymers are of appropriate sizes for parenteral administration. Thermodynamic results demonstrate that the presence of the dextran backbone structure does not affect the stability of the βCD/drug complex, compared to native βCD and commercially available derivatives. Solubility studies evidence higher solubilizing abilities of these new polymers in comparison to commercially available βCDs, but no supersaturation states were induced. Moreover, drug release studies evidenced that diffusion of HC was influenced by the solubilization induced by the βCD-derivatives. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Palladium(II)-catalyzed ortho-C-H arylation/alkylation of N-benzoyl α-amino ester derivatives.

    Science.gov (United States)

    Misal Castro, Luis C; Chatani, Naoto

    2014-04-14

    The palladium-catalyzed arylation/alkylation of ortho-C-H bonds in N-benzoyl α-amino ester derivatives is described. In such a system both the NH-amido and the CO2R groups in the α-amino ester moieties play a role in successful C-H activation/C-C bond formation using iodoaryl coupling partners. A wide variety of functional groups and electron-rich/deficient iodoarenes are tolerated. The yields obtained range from 20 to 95%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Hydrogen peroxide kinetics in water radiolysis

    Science.gov (United States)

    Iwamatsu, Kazuhiro; Sundin, Sara; LaVerne, Jay A.

    2018-04-01

    The kinetics of the formation and reaction of hydrogen peroxide in the long time γ- radiolysis of water is examined using a combination of experiment with model calculations. Escape yields of hydrogen peroxide on the microsecond time scale are easily measured with added radical scavengers even with substantial amounts of initial added hydrogen peroxide. The γ-radiolysis of aqueous hydrogen peroxide solutions without added radical scavengers reach a steady state limiting concentration of hydrogen peroxide with increasing dose, and that limit is directly proportional to the initial concentration of added hydrogen peroxide. The dose necessary to reach that limiting hydrogen peroxide concentration is also proportional to the initial concentration, but dose rate has a very small effect. The addition of molecular hydrogen to aqueous solutions of hydrogen peroxide leads to a decrease in the high dose limiting hydrogen peroxide concentration that is linear with the initial hydrogen concentration, but the amount of decrease is not stoichiometric. Proton irradiations of solutions with added hydrogen peroxide and hydrogen are more difficult to predict because of the decreased yields of radicals; however, with a substantial increase in dose rate there is a sufficient decrease in radical yields that hydrogen addition has little effect on hydrogen peroxide decay.

  7. Solubilization of tea seed oil in a food-grade water-dilutable microemulsion.

    Directory of Open Access Journals (Sweden)

    Lingli Deng

    Full Text Available Food-grade microemulsions containing oleic acid, ethanol, Tween 20, and water were formulated as a carrier system for tea seed oil (Camellia oleifera Abel.. The effect of ethanol on the phase behavior of the microemulsion system was clearly reflected in pseudo-ternary diagrams. The solubilization capacity and solubilization efficiency of tea seed oil dispersions were measured along the dilution line at a 70/30 surfactant/oil mass ratio with Tween 20 as the surfactant and oleic acid and ethanol (1:3, w/w as the oil phase. The dispersed phase of the microemulsion (1.5% weight ratio of tea seed oil to the total amount of oil, surfactant, and tea seed oil could be fully diluted with water without phase separation. Differential scanning calorimetry and viscosity measurements indicated that both the carrier and solubilized systems underwent a similar microstructure transition upon dilution. The dispersion phases gradually inverted from the water-in-oil phase ( 45% water along the dilution line.

  8. Surfactant-enhanced solubilization of residual dodecane in soil columns. 2. Mathematical modeling

    International Nuclear Information System (INIS)

    Abriola, L.M.; Dekker, T.J.; Pennell, K.D.

    1993-01-01

    A mathematical model is developed to describe surfactant-enhanced solubilization of nonaqueous-phase liquids (NAPLs) in porous media. The model incorporates aqueous-phase transport equations for organic and surfactant components as well as a mass balance for the organic phase. Rate-limited solubilization and surfactant sorption are represented by a linear driving force expression and a Langmuir isotherm, respectively. The model is implemented in a one-dimensional Galerkin finite element simulator which idealizes the entrapped residual organic as a collection of spherical globules. Soil column data for the solubilization of residual dodecane by an aqueous solution of polyoxyethylene (20) sorbitan monooleate are used to evaluate the conceptual model. Input parameters were obtained, where possible, from independent batch experiments. Calibrated model simulations exhibit good agreement with measured effluent concentrations, supporting the utility of the conceptual modeling approach. Sensitivity analyses explore the influence of surfactant concentration and flushing strategy on NAPL recovery. 45 refs., 6 figs., 3 tabs

  9. Solubilization and Interaction Studies of Bile Salts with Surfactants and Drugs: a Review.

    Science.gov (United States)

    Malik, Nisar Ahmad

    2016-05-01

    In this review, bile salt, bile salt-surfactant, and bile salt-drug interactions and their solubilization studies are mainly focused. Usefulness of bile salts in digestion, absorption, and excretion of various compounds and their rare properties in ordering the shape and size of the micelles owing to the presence of hydrophobic and hydrophilic faces are taken into consideration while compiling this review. Bile salts as potential bio-surfactants to solubilize drugs of interest are also highlighted. This review will give an insight into the selection of drugs in different applications as their properties get modified by interaction with bile salts, thus influencing their solution behavior which, in turn, modifies the phase-forming behavior, microemulsion, and clouding phenomenon, besides solubilization. Finally, their future perspectives are taken into consideration to assess their possible uses as bio-surfactants without side effects to human beings.

  10. Interpenetrating polymer networks based on polyol modified castor ...

    Indian Academy of Sciences (India)

    Interpenetrating polymer networks (IPNs) of glycerol modified castor oil polyurethane (GC–PU) and poly[2-hydroxyethylmethacrylate] (PHEMA) were synthesized using benzoyl peroxide as initiator and N,N-methylene bis acrylamide as crosslinker. GC–PU/PHEMA interpenetrating polymer networks were obtained by ...

  11. Sucrose derivatives and the selective benzoylation of the secondary hydroxyl groups of 6,1',6'-tri-O-tritylsucrose

    International Nuclear Information System (INIS)

    Holzapfel, C.W.; Koekemoer, J.M.; Marais, C.F.

    1984-01-01

    The preparation and 500 MHz 1 H-n.m.r. spectra of a number of sucrose derivatives are described. The assignment of the individual proton resonances in these compounds contributed to the identification of the mono- and dibenzoates obtained by benzoylation of 6,1',6'-tri-O-tritylsucrose following regioselective activation of the secondary hydroxyl groups by reaction with dibutyltin oxide or bis(tributyltin) oxide

  12. Evaluation of the influence of nitrogen fixing, phosphate solubilizing ...

    African Journals Online (AJOL)

    Three biofertilizers nitrobein, phosphorein, and potash, containing nitrogen fixing, phosphate solubilizing, and potash mobilizing microorganisms, respectively were studied in peanut (Arachis hypogea L.) and sunflower (Helianthus annuus L.). Amendment with each of these biofertilizers enhanced different growth ...

  13. Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

    OpenAIRE

    Lílian Estrela Borges Baldotto; Marihus Altoé Baldotto; Fábio Lopes Olivares; Adriane Nunes de Souza

    2014-01-01

    Besides fixing N2, some diazotrophic bacteria or diazotrophs, also synthesize organic acids and are able to solubilize rock phosphates, increasing the availability of P for plants. The application of these bacteria to pineapple leaf axils in combination with rock phosphate could increase N and P availability for the crop, due to the bacterial activity of biological nitrogen fixation and phosphate solubilization. The objectives of this study were: (i) to select and characterize diazotrophs abl...

  14. Management strategies for acne vulgaris

    Science.gov (United States)

    Whitney, Kristen M; Ditre, Chérie M

    2011-01-01

    Clinical question: What are the most effective treatment(s) for mild, moderate, severe, and hormonally driven acne? Results: Mild acne responds favorably to topical treatments such as benzoyl peroxide, salicylic acid, and a low-dose retinoid. Moderate acne responds well to combination therapy comprising-topical benzoyl peroxide, antibiotics, and/or retinoids, as well as oral antibiotics in refractory cases and oral contraceptive pills for female acne patients. Severe nodulocystic acne vulgaris responds best to oral isotretinoin therapy. In female patients with moderate to severe acne, facial hair, loss of scalp hair and irregular periods, polycystic ovarian syndrome should be considered and appropriate treatment with hormonal modulation given. Adjunctive procedures can also be considered for all acne patients. Implementation: Pitfalls to avoid when treating acne: treatment of acne in women of child-bearing age; familiarization of all acne treatments in order to individualize management for patients; indications for specialist referral. PMID:21691566

  15. Comparison of solubilized and purified plasma membrane and nuclear insulin receptors

    International Nuclear Information System (INIS)

    Wong, K.Y.; Hawley, D.; Vigneri, R.; Goldfine, I.D.

    1988-01-01

    Prior studies have detected biochemical and immunological differences between insulin receptors in plasma membranes and isolated nuclei. To further investigate these receptors, they were solubilized in Triton X-100 partially purified by wheat germ agglutinin-agarose chromatography. In these preparations, the nuclear and plasma membrane receptors had very similar pH optima (pH 8.0) and reactivities to a group of polyclonal antireceptor antibodies. Further, both membrane preparations had identical binding activities when labeled insulin was competed for by unlabeled insulin (50% inhibition at 800 pM). Next, nuclear and plasma membranes were solubilized and purified to homogeneity by wheat germ agglutinin-agarose and insulin-agarose chromatography. In both receptors, labeled insulin was covalently cross-linked to a protein of 130 kilodaltons representing the insulin receptor α subunit. When preparations of both receptors were incubated with insulin and then adenosine 5'-[γ- 32 P]triphosphate, a protein of 95 kilodaltons representing the insulin receptor β subunit was phosphorylated in a dose-dependent manner. These studies indicate, therefore, that solubilized plasma membrane and nuclear insulin receptors have similar structures and biochemical properties, and they suggest that they are the same (or very similar) proteins

  16. Physicochemical investigation of mixed surfactant microemulsions: water solubilization, thermodynamic properties, microstructure, and dynamics.

    Science.gov (United States)

    Bardhan, Soumik; Kundu, Kaushik; Saha, Swapan K; Paul, Bidyut K

    2013-12-01

    In this contribution, we report on a systematic investigation of phase behavior and solubilization of water in water-in-heptane or decane aggregates stabilized by mixtures of polyoxyethylene (20) cetyl ether (Brij-58) and cetyltrimethylammonium bromide (CTAB) surfactants with varying compositions in conjugation with 1-pentanol (Pn) at fixed surfactant(s)/Pn ratio and temperature. Synergism in water solubilization was evidenced by the addition of CTAB to Brij-58 stabilized system in close proximity of equimolar composition in both oils. An attempt has been made to correlate composition dependent water solubilization and volume induced conductivity studies to provide insight into the solubilization mechanism of these mixed systems. Conductivity studies reveal the ascending curve in water solubilization capacity-(Brij-58:CTAB, w/w) profile as the interdroplet interaction branch indicating percolation of conductance and the descending curve is a curvature branch due to the rigidity of the interface in these systems. The microstructure of these systems as a function of surfactant composition has been determined by dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) measurements. FTIR study reveals increase and decrease in relative population of bound and bulk-like water, respectively, with increase in Brij-58:CTAB (w/w). DLS measurements showed that the droplet hydrodynamic diameter (Dh) decreases significantly with the increase in Brij-58:CTAB (w/w). Further, the interfacial composition and energetic parameters for the transfer of Pn from bulk oil to the interface were evaluated by the dilution method. Formation of temperature-insensitive microemulsions and temperature invariant droplet sizes are evidenced in the vicinity of the equimolar composition. The results are interpreted in terms of a proposed mechanism. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Performance of phosphate solubilizing bacteria for improving growth ...

    African Journals Online (AJOL)

    The ability of phosphate solubilizing bacteria (PSB) to convert insoluble forms of phosphorus to an accessible form is an important trait in sustainable farming for increasing plant yields. The beneficial effects of PSB on crop productivity have been widely described, but the use of PSB as biofertilizer is scarcely documented in ...

  18. Tailoring the morphology and properties of poly(lactic acid)/poly(ethylene-co-vinyl acetate)/starch blends via reactive compatibilization

    NARCIS (Netherlands)

    Ma, P.; Hristova - Bogaerds, D.G.; Schmit, P.; Goossens, J.G.P.; Lemstra, P.J.

    2012-01-01

    Poly(lactic acid)/poly(ethylene-co-vinyl acetate)/starch (PLA/EVA/starch) ternary blends were prepared by multi-step melt processing (reactive extrusion) in the presence of maleic anhydride (MA), benzoyl peroxide and glycerol. The effects of MA and glycerol concentration on the morphology and

  19. Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey products

    Science.gov (United States)

    Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

  20. Influence of Bleaching on Flavor of 34% Whey Protein Concentrate and Residual Benzoic Acid Concentration in Dried Whey Proteins

    Science.gov (United States)

    Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

  1. Hydrogen peroxide as a sustainable energy carrier: Electrocatalytic production of hydrogen peroxide and the fuel cell

    International Nuclear Information System (INIS)

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D.

    2012-01-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal–oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  2. Hydrogen Peroxide as a Sustainable Energy Carrier: Electrocatalytic Production of Hydrogen Peroxide and the Fuel Cell.

    Science.gov (United States)

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D

    2012-11-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal-oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  3. Correlations Between retention indices and molecular structure of aliphatic alcohols and of their benzoyl derivatives on phenyl substituted polysiloxane stationary phases; Cromatografia en fase gaseosa sobre metilfenilpolisiloxanos. Estructura molecular y parametros de retencion para alcoholes y sus derivados benzoilados

    Energy Technology Data Exchange (ETDEWEB)

    Pias, J B; Gasco, L

    1976-07-01

    The retention indices of aliphatic alcohols of carbon number up to C{sub g}, and of their benzoyl derivatives up to C{sub 7}, were determined in columns packed with Chromo sorb G (AW-DMCS-HP) coated previously with 5% methyl, and methyl phenyl polysiloxanes with increasing polarity (SE-30, 0V-3, 0V-7, 0V-11, 0V-17 and OV-25). Correlations between retention indices and chain length for 1-alcohols, 2-alcohols, 3-alcohols, 1 , on -3-alcohols, 2-methyl-1-alcohols and for their corresponding benzoyl derivatives were calculated at 100, 120 and 140 degree centigree. In alcohols, a -CH{sub 2}- group increases I approximately 100 units, and in their benzoyl derivatives from 80 to 100 units. Dispersion indices {delta}l , and positional and structural increments {delta}I, were evaluated for -OH and benzoyl groups in terms of phase polarity and chain length. Effects of chain length, chain branching and double bond location on retention parameters were also studied. (Author) 23 refs.

  4. Identification of phosphate solubilizing bacteria in a Andisol of Colombian coffee region

    Directory of Open Access Journals (Sweden)

    Carlos Adolfo Cisneros Rojas

    2017-01-01

    Full Text Available Phosphorus is an essential nutrient for coffee growing, however, in Colombia most of the soils have low concentrations of this element. A strategy to supply the demand is the use of phosphate solubilizing microorganisms (PSM, in that order, 26 rhizospheric bacteria of Typic melanudans soil of Cajibío (Cauca, Colombia were isolated, in three agroecosystems: coffee at full sun exposure, coffee with shade and relic secondary forest, evaluating the phosphate solubilizing efficiency (PSE for Ca-P, Al-P, Fe-P in the solid and liquid Pikovskaya media. It showed the following solubilization sequence: Ca-P> Al-P> Fe-P. Two isolated bacteria were identified by DNA extraction and analysis of the 16S rRNA gene as Kocuria sp, and Bacillus subtilis. Later, using HPLC were identified organic acids present in the three phosphorus sources as: citric, gluconic, D- and L-malic, D- and L-lactic acid with higher presence in Ca-P-Kocuria sp. Strong acidification was observed for Fe-P and Al-P in all conditions.

  5. Solubilization of Australian lignites by fungi and other microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Catcheside, D.E.A.; Mallett, K.J. (Flinders University, Bedford Park, SA (Australia). School of Biological Sciences)

    Lignites (brown coals) from the Latrobe Valley in Victoria are solubilized by {ital Coriolus versicolor}, {ital Phanerochaete chrysosporium}, and five other species known to be active on Leonardite and various acid-treated North America lignites. Run-of-mine coal from Morwell and Loy Yang is refractory but is soluble after pretreatment with acid. A weathered deposit at Loy Yang, like Leonardite, is susceptible to biosolubilization without pretreatment. The white rot fungi {ital Ganoderma applanatum}, {ital Perenniporia tephropora} ({ital Fomes lividus}), {ital Pleurotus ostreatus}, {ital Pycnoporus cinnabarinus}, {ital Rigidoporus ulmarius}, and {ital Xylaria hypoxylon} were found to be capable of solubilizing lignite. In contrast, brown rot fungi were weakly active or inactive under the same test conditions. Lignite-degrading fungi, actinomycetes, and other bacteria, including some active on untreated run-of-mine coal, were isolated from natural lignite exposures and mining sites. 15 refs., 5 tabs.

  6. Benzoyl peroxide-induced damage to DNA and its components

    DEFF Research Database (Denmark)

    Hazlewood, C; Davies, Michael Jonathan

    1996-01-01

    of base adducts, though the exact identity of the species detected in these cases could not be determined due to the complexity of the spectra. Hydrogen abstraction at the sugar-phosphate backbone is also believed to occur with these substrates as strand breakage is observed; the extent of the latter...

  7. Solubilization of Na,K-ATPase from rabbit kidney outer medulla using only C12E8

    Directory of Open Access Journals (Sweden)

    H.L. Santos

    2002-03-01

    Full Text Available SDS, C12E8, CHAPS or CHAPSO or a combination of two of these detergents is generally used for the solubilization of Na,K-ATPase and other ATPases. Our method using only C12E8 has the advantage of considerable reduction of the time for enzyme purification, with rapid solubilization and purification in a single chromatographic step. Na,K-ATPase-rich membrane fragments of rabbit kidney outer medulla were obtained without adding SDS. Optimum conditions for solubilization were obtained at 4ºC after rapid mixing of 1 mg of membrane Na,K-ATPase with 1 mg of C12E8/ml, yielding 98% recovery of the activity. The solubilized enzyme was purified by gel filtration on a Sepharose 6B column at 4ºC. Non-denaturing PAGE revealed a single protein band with phosphomonohydrolase activity. The molecular mass of the purified enzyme estimated by gel filtration chromatography was 320 kDa. The optimum apparent pH obtained for the purified enzyme was 7.5 for both PNPP and ATP. The dependence of ATPase activity on ATP concentration showed high (K0.5 = 4.0 µM and low (K0.5 = 1.4 mM affinity sites for ATP, with negative cooperativity. Ouabain (5 mM, oligomycin (1 µg/ml and sodium vanadate (3 µM inhibited the ATPase activity of C12E8-solubilized and purified Na,K-ATPase by 99, 81 and 98.5%, respectively. We have shown that Na,K-ATPase solubilized only with C12E8 can be purified and retains its activity. The activity is consistent with the form of (alphaß2 association.

  8. Hydrophosphorylation of alkynes with phosphinous acids

    International Nuclear Information System (INIS)

    Nifant'ev, E.E.; Solovetskaya, L.A.; Magdeeva, R.K.

    1986-01-01

    A feature of the homolytic hydrophosphorylation of alkynes, as compared with alkenes, is more ready addition of phosphinous acids in presence of benzoyl peroxides. A difference was found in the hydrophosphorylation of acetylenes with dibutylphosphinous acid and with diarylphosphinous acids: the latter tend to form diaddition products

  9. 76 FR 78259 - Valeant Pharmaceuticals International, Inc.; Analysis of Agreement Containing Consent Order to...

    Science.gov (United States)

    2011-12-16

    ....ftc.gov/os/publiccomments.shtm . As a matter of discretion, the Commission tries to remove individuals... clindamycin, an antibiotic, and benzoyl peroxide, an antimicrobial. Valeant owns the only Abbreviated New Drug... time consuming. Developing and obtaining U.S. Food and Drug Administration approval for the manufacture...

  10. 21 CFR 133.102 - Asiago fresh and asiago soft cheese.

    Science.gov (United States)

    2010-04-01

    ... finished cheese having the same physical and chemical properties as the cheese produced when the procedure... purified calcium chloride in a quantity not more than 0.02 percent (calculated as anhydrous calcium... benzoyl peroxide with potassium alum, calcium sulfate, and magnesium carbonate; but the weight of the...

  11. Different strategies of fungi to solubilize coal: a comparison of the deutermycetes Trichoderma atroviride and Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Hoelker, U.; Ludwig, S.; Moenkemann, H.; Scheel, T.; Hoefer, M. [Bonn Univ. (Germany). Botanisches Inst.

    1997-12-31

    Four different mechanisms can be envisaged which are used by microorganisms to solubilize coal: the production of alkaline substances, the extrusion of chelators, the action of biotensides, and of special interest in terms of biotechnology, the action of enzymes. Whether these mechanisms are operating seperately or in varying combinations has not yet been settled. The two deuteromycetes Fusarium oxysporum and Trichoderma altroviride solubilize coal by synergistic effects of different mechanisms depending on the cell metabolism. F. oxysporum seems to solubilize coal by increasing the pH of the mycelial surroundings and by the action of chelators induced during growth in glutamate containing media (without involvement of enzymes). T. atroviride, on the other hand, appears to use, in addition to an alkaline pH and a high chelator activity, at least two classes of enzymes to attack coal: hydrolytic activity for coal solubilization and ligninolytic activity for degradation of humic acids. (orig.)

  12. Determination of molybdenum in various materials by normal-phase liquid chromatography using N-benzoyl-N-phenylhydroxylamine

    International Nuclear Information System (INIS)

    Bagur, Gracia; Sanchez-Vinas, Mercedes; Gazquez, Domingo

    1995-01-01

    A normal-phase liquid chromatographic method for the selective determination of molybdenum with N-benzoyl-N-phenylhydroxylamine is described. The molybdenum(VI) complex was preconcentrated by extraction into chloroform and injected onto a nitrile column for chromatography. The mobile phase was a 0.075 M solution of reagent in chloroform (stabilized with amylene). The detection limit for molybdenum by the proposed method was 0.88 ng for a phase volume ratio of 20:1 (aqueous to organic). Molybdenum has been determined in several samples with satisfactory accuracy and precision

  13. Detection of hydrogen peroxide with graphyne

    Science.gov (United States)

    Majidi, R.; Karami, A. R.

    2013-12-01

    The effect of hydrogen peroxide on the electronic properties of graphyne has been investigated to explore the possibility of using graphyne based biosensor. We have used density functional theory to study the electronic properties of γ-graphyne in the presence of different number of hydrogen peroxide. The optimal adsorption position, orientation, and distance of hydrogen peroxide adsorbed on the graphyne sheet have been determined by calculating adsorption energy. It is found that γ-graphyne which is an intrinsic semiconductor becomes an n-type semiconductor due to the presence of hydrogen peroxide. The energy band gap of γ-graphyne is decreased by increasing the number of hydrogen peroxide. The results demonstrate that γ-graphyne is a promising candidate for biosensor application because of its electrical sensitivity to hydrogen peroxide.

  14. The population of phosphate solubilizing bacteria (PSB from Cikaniki, Botol Mountain, and Ciptarasa Area, and the ability of PSB to solubilize insoluble P in solid pikovskaya medium

    Directory of Open Access Journals (Sweden)

    SULIASIH

    2006-04-01

    Full Text Available Phosphate solubilizing bacteria (PSB were collected from plant rhizosphere at Cikaniki (1100 m asl., soil at Botol Mountain (1000, 1500, and 1800 m asl., and Ciptarasa (600, 1000, and 1500 m asl., area at Gunung Halimun National Park (GHNP. The soil ware collected randomly from 3 areas and taken from 0-15 cm depth in the plants rhizosphere at Cikaniki and forest floor soil in Gunung Botol and Ciptarasa. The result showed that the difference of elevation area, soil pH, forest vegetation, and microbial habitat (rhizosphere and forest floor were not the inhabitation factors of the biodiversity of PSB and their ability to solubilize insoluble phosphate, but the inhabitation factors on the growth of the PSB population. The highest population of PSB at GHNP was founded in the plant rhizosphere of Altingia exelsa Norona and Schima wallichii (Dc. Korth (107sel/g soil at Cikaniki and in the forest floor soil (108sel/g soil at Botol Mountain (1000 m asl.. Pseudomonas sp., Bacillus sp., Bacillus megaterium, and Chromobacterium sp. dominated Cikaniki, Botol Mountain and Ciptarasa area. Those isolates could solubilize insoluble phosphate on solid Pikovskaya medium with the range of diameter is 1.5-2.5 cm.

  15. Solubilization and reconstitution of the formylmethionylleucylphenylalanine receptor coupled to guanine nucleotide regulatory protein

    International Nuclear Information System (INIS)

    Williamson, K.; Dickey, B.F.; Pyun, H.Y.; Navarro, J.

    1988-01-01

    The authors describe the solubilization, resolution, and reconstitution of the formylmethionylleucylphenylalanine (fMet-Leu-Phe) receptor and guanine nucleotide regulatory proteins (G-proteins). The receptor was solubilized with 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. Guanine nucleotides decreased the number of high-affinity binding sites and accelerated the rate of dissociation of the receptor-ligand complex, suggesting that the solubilized receptor remained coupled to endogenous G-proteins. The solubilized receptor was resolved from endogenous G-proteins by fractionation on a wheat germ agglutinin (WGA)-Sepharose 4B column. High-affinity [ 3 H]fMet-Leu-Phe binding to the WGA-purified receptor was diminished and exhibited reduced guanine nucleotide sensitivity. High-affinity [ 3 H]fMET-Leu-Phe binding and guanine nucleotide sensitivity were reconstituted upon the addition of purified brain G-proteins. Similar results were obtained when the receptor was reconstituted with brain G-proteins into phospholipid vesicles by gel filtration chromatography. In addition, they also demonstrated fMET-Leu-Phe-dependent GTP hydrolysis in the reconstituted vesicles. The results of this work indicate that coupling of the fMet-Leu-Phe receptor to G-proteins converts the receptor to a high-affinity binding state and that agonist produces activation of G-proteins. The resolution and functional reconstitution of this receptor should provide an important step toward the elucidation of the molecular mechanism of the fMet-Leu-Phe transduction system in neutrophils

  16. High temperature concrete composites containing organosiloxane crosslinked copolymers

    Science.gov (United States)

    Zeldin, A.; Carciello, N.; Kukacka, L.; Fontana, J.

    High temperature polymer concrete composites comprising about 10 to 30% by weight of a liquid monomer mixture is described. It consists essentially of an organosiloxane polymer crosslinked with an olefinically unsaturated monomer selected from the group consisting of styrene, methyl methacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, n-phenylmalimide, divinyl benzene and mixtures thereof. About 70 to 90% by weight of an inert inorganic filler system containing silica sand and portland cement, Fe/sub 2/O/sub 3/, carbon black or mixtures thereof. Optionally a free radical initiator such as di-tert-butyl peroxide, azobisisobyutyronitrile, benzoyl peroxide, lauryl peroxide and other organic peroxides are used to initiate crosspolymerization of the monomer mixture in the presence of the inorganic filler.

  17. Effect of phosphate-solubilizing bacteria isolated from semiarid soils on pitahaya seedlings (Hylocereus undatus)

    OpenAIRE

    Bautista-Cruz, Angélica; Ortiz-Hernández, Yolanda Donají; Martínez-Gallegos, Verónica; Martínez Gutiérrez, Gabino

    2015-01-01

    Phosphate-solubilizing bacteria (PSB) are a group of organisms that solubilize fixed forms of phosphorus, making it available for the plant growth. The effect of three PSB strains, called PSBMi, PSBHc and PSBVa, on growth of pitahaya seedlings (Hylocereus undatus) was studied in a growth chamber. The results indicated that plant stem diameter, plant height, plant total dry weight and root length were greatest in pitahaya seedlings inoculated with PSBMi. The increase in these plant growth vari...

  18. Sodium deoxycholate mediated enhanced solubilization and stability of hydrophobic drug Clozapine in pluronic micelles

    Science.gov (United States)

    Singla, Pankaj; Singh, Onkar; Chabba, Shruti; Aswal, V. K.; Mahajan, Rakesh Kumar

    2018-02-01

    In this report, the solubilization behaviour of a hydrophobic drug Clozapine (CLZ) in micellar suspensions of pluronics having different hydrophilic lipophilic balance (HLB) ratios viz. P84, F127 and F108 in the absence and presence of bile salt sodium deoxycholate (SDC) has been studied. UV-Vis spectroscopy has been exploited to determine the solubilization capacity of the investigated micellar systems in terms of drug loading efficiency, average number of drug molecules solubilized per micelle (ns), partition coefficient (P) and standard free energy of solubilization (Δ G°). The morphological and structural changes taking place in pluronics in different concentration regimes of SDC and with the addition of drug CLZ has been explored using dynamic light scattering (DLS) and small angle neutron scattering (SANS) measurements. The SANS results revealed that aggregation behaviour of pluronic-SDC mixed micelles gets improved in the presence of drug. The micropolarity measurements have been performed to shed light on the locus of solubilization of the drug in pure and mixed micellar systems. The compatibility between CLZ and drug carriers (pluronics and SDC) was confirmed using powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) techniques. Among the investigated systems, P84-SDC mixed system was found to be highly efficient for CLZ loading. The long term stability data indicated that CLZ loaded P84-SDC mixed micellar formulation remained stable for 3 months at room temperature. Further, it was revealed that the CLZ loaded P84-SDC mixed micelles are converted into CLZ loaded pure P84 micelles at 30-fold dilutions which remain stable up to 48-fold dilutions. The results from the present studies suggest that P84-SDC mixed micelles can serve as suitable delivery vehicles for hydrophobic drug CLZ.

  19. Synthesis and characterization of castor oil based polyurethane ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. A series of interpenetrating polymer networks (IPNs) of castor oil based polyurethane/polyacrylo- nitrile (PU/PAN: 80/20, 60/40, 50/50, 40/60 and 20/80) were synthesized by condensation reaction of castor oil with methylene diisocyanate and acrylonitrile, employing benzoyl peroxide (BPO) and ethylene glycol ...

  20. The ability of rhizobacteria to solubilize phosphate and synthesize of indoleacetic acid in cowpea

    Directory of Open Access Journals (Sweden)

    Weslany Silva Rocha

    2018-01-01

    Full Text Available The Cerrado comprises a vast ecoregion in central Brazil where plants show both growth and nitrogen fixation deficiencies due to low soil fertility. Farmers may overcome such problem using species of microorganisms capable of improving soil fertility such as the Rhizobia bacteria. This work aimed to assess the ability of phosphate solubilization and synthesis of indoleacetic acid (IAA of Rhizobium isolates obtained from Cerrado soils in the state of Tocantins, Brazil, evaluating their symbiotic efficiency in cowpea (Vigna unguiculata L. Walp. plants. We used a total of 32 isolates (or strains of Rhizobium and a reference species of Bradyrhizobium. The capacity of phosphate solubilization and synthesis of IAA was evaluated in vitro, while the symbiotic function of rhizobia isolates and the effect on cowpea biomass was assessed in a greenhouse. Only eight strains were able to solubilize calcium phosphate, while all isolates produced IAA. The rhizobia inoculation caused a significant increase in biomass and nodulation of cowpea. The isolates UFT R122 and UFT R124 stood out with the highest values for the studied parameters, showing rises above 33% of relative efficiency in comparison to the treatment with nitrogen fertilization. By associating the results of phosphate solubilization capacity, IAA synthesis, symbiotic ability, and nodulation, we conclude that the isolates that showed good performance are potential inoculants for cowpea in Cerrado soils.

  1. Problem of the lithium peroxide thermal stability

    International Nuclear Information System (INIS)

    Nefedov, R A; Ferapontov, Yu A; Kozlova, N P

    2016-01-01

    The behavior of lithium peroxide and lithium peroxide monohydrate samples under heating in atmospheric air was studied by the method of thermogravimetric analysis (TGA) and differential thermal analysis (DTA). It was found that in the temperature range of 32°C to 82°C the interaction of lithium peroxides and steam with the formation of lithium peroxide monohydrate occurs, which was confirmed chemically and by X-ray Single-qualitative analysis. It was experimentally found that lithium peroxide starts to decompose into the lithium oxide and oxygen in the temperature range of 340 ÷ 348°C. It was established that the resulting thermal decomposition of lithium oxide, lithium peroxide at the temperature of 422°C melts with lithium carbonate eutecticly. The manifestation of polymorphism was not marked(seen or noticed) under the heating of studied samples of lithium peroxide and lithium peroxide monohydrate in the temperature range of 25°C ÷ 34°C. (paper)

  2. Water solubilization capacity of pharmaceutical microemulsions based on Peceol®, lecithin and ethanol.

    Science.gov (United States)

    Mouri, Abdelkader; Diat, Olivier; Lerner, Dan Alain; El Ghzaoui, Abdeslam; Ajovalasit, Alessia; Dorandeu, Christophe; Maurel, Jean-Claude; Devoisselle, Jean-Marie; Legrand, Philippe

    2014-11-20

    Biocompatible microemulsions composed of Peceol(®), lecithin, ethanol and water developed for encapsulation of hydrophilic drugs were investigated. The binary mixture Peceol(®)/ethanol was studied first. It was shown that the addition of ethanol to pure Peceol(®) has a significant fluidifying and disordering effect on the Peceol(®) supramolecular structure with an enhancement in water solubilization. The water solubilization capacity was improved by adding lecithin as a third component. It was then demonstrated that the ethanol/lecithin weight ratio played an important role in determining the optimal composition in term of water solubilization efficiency, a necessary property for a nutraceutical or pharmaceutical application. The optimal ethanol/lecithin weight ratio in the Peceol(®) rich region was found to be 40/60. Combination different techniques such as SAXS, fluorimetry, rheology and conductivity, we analyzed the water uptake within the microemulsion taking into account the partitioning of ethanol between polar and apolar domains. This ethanol distribution quantified along a water dilution line has a major effect on microemulsion properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Isolation and characterization of a phosphate solubilizing heavy metal tolerant bacterium from River Ganga, West Bengal, India

    Directory of Open Access Journals (Sweden)

    Dipak Paul

    2015-12-01

    Full Text Available Phosphates solubilizing bacterial (PSB strains were isolated from the jute mill effluent discharge area of the Ganga river water at Bansberia, West Bengal, India. Experimental studies found that the strain KUPSB16 was effective in solubilization of phosphate with phosphate solubilization index (SI = 3.14 in Pikovskaya’s agar plates along with maximum solubilized phosphate production of 208.18 g mL-1 in broth culture. Highest drop in pH value was associated with maximum amount of phosphate solubilization by the PSB strain KUPSB16 where pH decreased to 3.53 from initial value of 7.0±0.2. The isolated PSB strains were tested for tolerance against four heavy metals such as cadmium (Cd, chromium (Cr, lead (Pb and zinc (Zn at concentrations 1-15 mM. The results showed that most of the PSB isolates grew well at low concentrations of heavy metals and their number gradually decreased as the concentration increased. Isolated PSB strain KUPSB16 was tested for its multiple metal resistances. Minimal inhibitory concentrations (MIC for Cd2+, Cr6+, Pb2+ and Zn2+ in tris-minimal broth medium were 4.2, 5.5, 3.6 and 9.5 mM respectively. The MIC values for the metals studied on agar medium was higher than in broth medium and ranged from 4.8-11.0 mM. The isolated bacterial strain KUPSB16 was subjected to morphological, physiological and biochemical characterization and identified as the species of the genus Bacillus. The phosphate solubilizing bacterium possessing the properties of multiple heavy metal tolerance in heavy metal contaminated areas might be exploited for bioremediation studies in future.

  4. A New Benzoyl Compound Isolated from the Endophytic Fungi of Kandis Gajah (Garcinia griffithii and Asam Kandis (Garcinia cowa

    Directory of Open Access Journals (Sweden)

    Elfita Elfita

    2016-12-01

    Full Text Available Garcinia griffithii and Garcinia cowa belong to the genus Garcinia. The genus Garcinia has been known to be a rich source of secondary metabolites, such as xanthones, benzophenones, flavonoids, steroids, terpenoids, and other phenolic derivatives. Previous investigations of endophytic fungi from G. griffithii revealed the presence of three compounds not found in the host. In order to the continue the phytochemical work on endophytic fungi of G. griffithii, the constituent of the endophytic fungi of G. griffithii was re-examined. In this study, a benzoyl compound similar to that found in the endophytic fungus of G. cowa was observed. The same benzoyl compound was also isolated from the endophytic fungus Acremonium sp of G. griffithii and Aspergillus sp of G. cowa with cultivation of eight weeks in static conditions at room temperature. The culture medium was partitioned using ethyl acetate and evaporated to obtain the concentrated extract. Isolation of compounds was performed using the chromatography method. The chemical structure was proposed on the basis of spectroscopic data, including ultraviolet (UV, infrared (IR, mass spectrometry (MS, proton nuclear magnetic resonance (1H-NMR, carbon nuclear magnetic resonance (13C-NMR, heteronuclear single-quantum correlation spectroscopy (HSQC, heteronuclear multiple-bond correlation spectroscopy (HMBC, and correlation spectroscopy (COSY.

  5. A novel surfactant S-benzoyl-N,N-diethyldithiocarbamate synthesis and its flotation performance to galena

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xin; Hu, Yuan; Zhong, Hong, E-mail: zhongh@csu.edu.cn; Wang, Shuai, E-mail: wangshuai@csu.edu.cn; Liu, Guangyi; Zhao, Gang

    2016-03-01

    Graphical abstract: - Highlights: • A novel surfactant BEDTC was first introduced as galena flotation collector. • BEDTC exhibited superior collecting power to galena against sphalerite. • BEDTC has two active centers to mineral surfaces. • BEDTC molecules formed two distinct adsorption geometries on galena surfaces. - Abstract: In this paper, a novel dithiocarbamate compound, S-benzoyl-N,N-diethyldithiocarbamate (BEDTC), was synthesized via one-pot reaction of diethylamine, carbon disulfide, sodium hydroxide and benzoyl chloride using abundant carbon disulfide as a solvent. Its flotation performance and adsorption mechanism on the galena was first investigated by flotation tests, adsorption quantity measurements, FTIR spectra, X-ray photoelectron spectra (XPS) and density functional theory (DFT) calculation. The flotation results illustrated that BEDTC exhibited stronger collecting power than the conventional sulphide collectors such as sodium diethyl dithiocarbamate (SEDTC) and sodium isobutyl xanthate (SIBX) and superior selectivity for galena against sphalerite. The adsorption data demonstrated that the adsorption affinity of BEDTC to galena was stronger than that of SEDTC and SIBX, and the preferable pH range for BEDTC adsorption on galena surfaces was 6–10. The results of FTIR spectra and XPS indicated that the interaction of BEDTC with galena may be dominated by the chemical adsorption, which was further confirmed by DFT calculation. BEDTC probably acted as a bidentate ligand, bonding with lead through the thiol sulfur and carbonyl oxygen atoms to form two distinct adsorption geometries, one with the same Pb atom to form a six-membered ring complex, and the other with two different Pb atoms to form a ''bullet'' shape complex.

  6. Optimized conditions for high-level solubilization and purification of ...

    African Journals Online (AJOL)

    In this report, we describe the cloning, over-expression, efficient solubilization, purification and evaluation of bioactivity of camel growth hormone (cGH). The total cellular RNA was extracted from pituitary glands of freshly slaughtered animals and cDNA of cGH was synthesized by a pair of sequence specific primers with a ...

  7. Gluconic acid production and phosphate solubilization by the plant growth-promoting bacterium Azospirillum spp.

    Science.gov (United States)

    Rodriguez, Hilda; Gonzalez, Tania; Goire, Isabel; Bashan, Yoav

    2004-11-01

    In vitro gluconic acid formation and phosphate solubilization from sparingly soluble phosphorus sources by two strains of the plant growth-promoting bacteria A. brasilense (Cd and 8-I) and one strain of A. lipoferum JA4 were studied. Strains of A. brasilense were capable of producing gluconic acid when grown in sparingly soluble calcium phosphate medium when their usual fructose carbon source is amended with glucose. At the same time, there is a reduction in pH of the medium and release of soluble phosphate. To a greater extent, gluconic acid production and pH reduction were observed for A. lipoferum JA4. For the three strains, clearing halos were detected on solid medium plates with calcium phosphate. This is the first report of in vitro gluconic acid production and direct phosphate solubilization by A. brasilense and the first report of P solubilization by A. lipoferum. This adds to the very broad spectrum of plant growth-promoting abilities of this genus.

  8. Substitution Effects and Linear Free Energy Relationships During Reduction of 4- Benzoyl-n-(4-substituted Benzyl)pyridinium Cations

    Science.gov (United States)

    Leventis, Nicholas; Zhang, Guo-Hui; Rawashdeh, Abdel-Monem M.; Sotiriou-Leventis, Chariklia; Gray, Hugh R. (Technical Monitor)

    2003-01-01

    In analogy to 4-(para-substituted benzoyl)-N-methylpyridinium cations (1-X's), the title species (2-X's, -X = -OCH3, -CH3, -H, -Br, -COCH3, -NO2) undergo two reversible, well-separated (E(sub 1/2) greater than or equal to 650 mV) one-electron reductions. The effect of substitution on the reduction potentials of 2-X's is much weaker than the effect of the same substituents on 1-X's: the Hammett rho-values are 0.80 and 0.93 for the 1st- and 2nd-e reduction of 2-X's vs. 2.3 and 3.3 for the same reductions of 1-X's, respectively. Importantly, the nitro group of 2-NO2 undergoes reduction before the 2nd-e reduction of the 4-benzoylpyridinium system. These results suggest that the redox potentials of the 4-benzoylpyridinium system can be course-tuned via p-benzoyl substitution and fine-tuned via para-benzyl substitution. Introducing the recently derived substituent constant of the -NO2(sup)- group (sigma para-NO2(sup)- = -0.97) yields an excellent correlation for the 3rd-e reduction of 2- NO2 (corresponding to the reduction of the carbonyl group) with the 2nd-e reduction of the other 2-X's, and confirms the electron donating properties of -NO2(sup)-.

  9. Effects of oil dispersant on solubilization, sorption and desorption of polycyclic aromatic hydrocarbons in sediment–seawater systems

    International Nuclear Information System (INIS)

    Zhao, Xiao; Gong, Yanyan; O’Reilly, S.E.; Zhao, Dongye

    2015-01-01

    Highlights: • Oil dispersant enhances solubilization of PAHs more effectively than surfactants. • Dispersant and dispersed oil enhance sediment sorption of PAHs and induce hysteresis. • Partitioning to sediment-sorbed dispersant is the mechanism for enhanced PAH uptake. • Dual-mode models well simulate dispersant-facilitated sorption of PAHs on sediment. • Deepwater conditions reduce solubilization of PAHs and lessen dispersant effects. - Abstract: This work investigated effects of a prototype oil dispersant on solubilization, sorption and desorption of three model PAHs in sediment–seawater systems. Increasing dispersant dosage linearly enhanced solubility for all PAHs. Conversely, the dispersant enhanced the sediment uptake of the PAHs, and induced significant desorption hysteresis. Such contrasting effects (adsolubilization vs. solubilization) of dispersant were found dependent of the dispersant concentration and PAH hydrophobicity. The dual-mode models adequately simulated the sorption kinetics and isotherms, and quantified dispersant-enhanced PAH uptake. Sorption of naphthalene and 1-methylnaphthalene by sediment positively correlated with uptake of the dispersant, while sorption of pyrene dropped sharply when the dispersant exceeded its critical micelle concentration (CMC). The deepwater conditions diminished the dispersant effects on solubilization, but enhanced uptake of the PAHs, albeit sorption of the dispersant was lowered. The information may aid in understanding roles of dispersants on distribution, fate and transport of petroleum PAHs in marine systems

  10. Effect of rhamnolipid biosurfactant on solubilization of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Li, Shudong; Pi, Yongrui; Bao, Mutai; Zhang, Cong; Zhao, Dongwei; Li, Yiming; Sun, Peiyan; Lu, Jinren

    2015-12-15

    Rhamnolipid biosurfactant-producing bacteria, Bacillus Lz-2, was isolated from oil polluted water collected from Dongying Shengli oilfield, China. The factors that influence PAH solubilization such as biosurfactant concentration, pH, ionic strength and temperature were discussed. The results showed that the solubilities of naphthalene, phenanthrene and pyrene increased linearly with the rise of rhamnolipid biosurfactant dose above the biosurfactant critical micelle concentration (CMC). Furthermore, the molar solubilization ratio (MSR) values decreased in the following order: naphthalene>phenanthrene>pyrene. However, the solubility percentage increased and followed the opposite order: pyrene>phenanthrene>naphthalene. The solubilities of PAHs in rhamnolipid biosurfactant solution increased with the rise of pH and ionic strength, and reached the maximum values under the conditions of pH11 and NaCl concentration 8 g · L(-1). The solubility of phenanthrene and pyrene increased with the rise of temperature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Measuring chlorophyll a and 14C-labeled photosynthate in aquatic angiosperms by the use of a tissue solubilizer

    International Nuclear Information System (INIS)

    Beer, S.; Stewart, A.J.; Wetzel, R.G.

    1982-01-01

    A compound that quantitatively correlated with chlorophyll a could be measured fluorometrically in the extracts of leaves of three aquatic angiosperms (Myriophyllum heterophyllum Michx., Potamogeton crispus L., Elodea canadensis Michx.) treated with the tissue solubilizer BTS-450. Fluorescent characteristics of the solubilized plant tissues were stable for several weeks in the dark at temperatures up to 60 0 C but rapidly degraded in sunlight or when acidified. 14 C-Labeled photosynthate, which had been fixed by leaf discs during 1- to 10-hour exposure to H 14 CO 3 , was also readily extracted by the tissue solubilizer. Solubilizer extraction can, therefore, be use to determine both chlorophyll a content and 14 C incorporation rates in the same leaf sample. The method is practical, because no grinding is required, the fluorescent characteristics of the extracts are stable, and analyses can be performed with very little plant material

  12. 21 CFR 133.111 - Caciocavallo siciliano cheese.

    Science.gov (United States)

    2010-04-01

    ... properties as the cheese produced when the procedure set forth in paragraph (b) of this section is used. It... purified calcium chloride in a quantity not more than 0.02 percent, calculated as anhydrous calcium... of benzoyl peroxide with potassium alum, calcium sulfate, and magnesium carbonate; but the weight of...

  13. Reactive compatibilization of ethylene-co-vinyl acetate/starch blends

    NARCIS (Netherlands)

    Ma, P.; Hristova - Bogaerds, D.G.; Schmit, P.; Goossens, J.G.P.; Lemstra, P.J.

    2012-01-01

    The dispersion of starch as a filler in hydrophobic ethylene-co-vinyl acetate (EVA) rubber is an issue. To obtain a fine dispersion of starch in EVA rubber, EVA/starch blends were prepared by reactive extrusion in the pres- ence of maleic anhydride (MA), benzoyl peroxide (BPO), and glycerol. MA,

  14. Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide

    International Nuclear Information System (INIS)

    Grasso, Andrea Nastri

    2010-01-01

    In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

  15. β-Cyclodextrin-dextran polymers for the solubilization of poorly soluble drugs

    DEFF Research Database (Denmark)

    Di Cagno, Massimiliano; Nielsen, Thorbjørn Terndrup; Lambertsen Larsen, Kim

    2014-01-01

    The aim of this work was to assess the potential of β-cyclodextrin (β-CD)-dextran polymers for drug delivery, in terms of molecular mass, the complexation reaction mechanism using a model drug, and solubilization efficiency for examples of poorly soluble model drugs. For this purpose size analysis...... of different β-CD-dextrans was carried out by both size exclusion chromatography (SEC) and flow field-flow fractionation (FFF). All investigated polymers were of appropriate sizes for potential parenteral administration. Mass/mass percentage ratio between β-CD units and dextran backbones where measured by both...... of solubilization efficiencies, phase-solubility diagrams where made employing two poorly soluble model drugs, one dissociating (ibuprofen, IBP) and one pH independent (hydrocortisone, HC). Thermodynamic results demonstrated that the presence of the dextran-back bone structure improves complexation efficiency...

  16. 21 CFR 529.1150 - Hydrogen peroxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hydrogen peroxide. 529.1150 Section 529.1150 Food... DRUGS, FEEDS, AND RELATED PRODUCTS CERTAIN OTHER DOSAGE FORM NEW ANIMAL DRUGS § 529.1150 Hydrogen peroxide. (a) Specifications. Each milliliter of solution contains 396.1 milligrams (mg) hydrogen peroxide...

  17. Quaternary structure of the lactose transport protein of Streptococcus thermophilus in the detergent-solubilized and membrane-reconstituted state

    NARCIS (Netherlands)

    Friesen, R.H.E.; Poolman, B.; Knol, J.

    2000-01-01

    The quaternary structure of LacS, the lactose transporter of Streptococcus thermophilus, has been determined for the detergent-solubilized and the membrane-reconstituted state of the protein. The quaternary structure of the n-dodecyl-β-D-maltoside-solubilized state was studied using a combination of

  18. Human proton coupled folic acid transporter is a monodisperse oligomer in the lauryl maltose neopentyl glycol solubilized state

    DEFF Research Database (Denmark)

    Aduri, Nanda G.; Ernst, Heidi A.; Prabhala, Bala K.

    2018-01-01

    and purification of recombinant PCFT. Following detergent screening n-Dodecyl β-D-maltoside (DDM) and lauryl maltose neopentyl glycol (LMNG) were chosen for further work as they exhibited the most optimal solubilization. We found that purified detergent solubilized PCFT was able to bind folic acid, thus indicating...

  19. Occurrence of symbiotic fungi and rhizospheric phosphate solubilization in weeds - doi: 10.4025/actasciagron.v35i1.15047

    Directory of Open Access Journals (Sweden)

    Edson Aparecido dos Santos

    2012-08-01

    Full Text Available Studies on the ecology of the organisms involved in the production process are necessary for the development of sustainable agriculture, and sustainability is currently closely linked to the profitability of production. The objective of this study was to verify the occurrence of arbuscular mycorrhizal fungi in weeds infesting Brazilian crops and to evaluate the inorganic phosphate solubilization potential of the associated microbiota. A total of 36 weed species were evaluated for the occurrence of mycorrhizae; of these, 11 were selected to evaluate their potential for total and relative phosphate solubilization. All of the species demonstrated mycorrhizal colonization, including a member of the Brassicaceae family, which is usually assumed to be non-mycorrhizal. In most of the species, morphological types of arbuscular and coiled hyphae were observed, with the coiled hyphae being the most common in the grasses. Dark septate endophytic fungi were observed in most of the plants. The weeds presented different potentials for P solubilization in the rhizosphere; Amaranthus retroflexus, Bidens pilosa and Leonotis nepetaefolia showed high values of relative phosphate solubilization. This is the first report on the mycorrhizae and phosphate solubilization activity in weeds in Brazil.

  20. Polymer synthesis in ionic liquids : towards a green industry

    NARCIS (Netherlands)

    Guerrero-Sanchez, C.A.; Schubert, U.S.

    2004-01-01

    The screening of six ionic liqs. used as reaction media in free radical polymn. of Me methacrylate and styrene was performed. AIBN was used as initiator for the polymn. of Me methacrylate and benzoyl peroxide in the case of styrene. Soly. of the used ionic liqs. in these monomers and water was also

  1. Reaction of 11 C-benzoyl chlorides with metalloid reagents: 11 C-labeling of benzyl alcohols, benzaldehydes, and phenyl ketones from [11 C]CO.

    Science.gov (United States)

    Roslin, Sara; Dahl, Kenneth; Nordeman, Patrik

    2018-01-26

    In this article, we describe the carbon-11 ( 11 C, t 1/2  = 20.4 minutes) labeling of benzyl alcohols, benzaldehydes, and ketones using an efficient 2-step synthesis in which 11 C-carbon monoxide is used in an initial palladium-mediated reaction to produce 11 C-benzoyl chloride as a key intermediate. In the second step, the obtained 11 C-benzoyl chloride is further treated with a metalloid reagent to furnish the final 11 C-labeled product. Benzyl alcohols were obtained in moderated to high non-isolated radiochemical yields (RCY, 35%-90%) with lithium aluminum hydride or lithium aluminum deuteride as metalloid reagent. Changing the metalloid reagent to either tributyltin hydride or sodium borohydride, allowed for the reliable syntheses of 11 C-benzaldehydes in RCYs ranging from 58% to 95%. Finally, sodium tetraphenylborate were utilized to obtain 11 C-phenyl ketones in high RCYs (77%-95%). The developed method provides a new and efficient route to 3 different classes of compounds starting from aryl iodides or aryl bromides. Copyright © 2018 John Wiley & Sons, Ltd.

  2. Self-diffusion nuclear magnetic resonance, microstructure transitions, and solubilization capacity of phytosterols and cholesterol in Winsor IV food-grade microemulsions

    DEFF Research Database (Denmark)

    Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham

    2003-01-01

    Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phytosterols, cholesterol-lowering agents, in food products is of great interest...... to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12...... times more than the dissolution capacity of the oil [R-(+)-limonene] for the same compounds. The solubilization capacity of phytosterols and cholesterol along a dilution line in a pseudo-ternary phase diagram [on this dilution line the weight ratio of R-(+)-limonene/ethanol/Tween 60 is constant at 1...

  3. OxymaPure/DIC: An Efficient Reagent for the Synthesis of a Novel Series of 4-[2-(2-Acetylaminophenyl-2-oxo-acetylamino] Benzoyl Amino Acid Ester Derivatives

    Directory of Open Access Journals (Sweden)

    Ayman El-Faham

    2013-11-01

    Full Text Available OxymaPure (ethyl 2-cyano-2-(hydroxyiminoacetate was tested as an additive for use in the carbodiimide (DIC approach for the synthesis of a novel series of α-ketoamide derivatives (4-[2-(2-acetylaminophenyl-2-oxo-acetylamino]benzoyl amino acid ester derivatives. OxymaPure showed clear superiority to HOBt/DIC or carbodiimide alone in terms of purity and yield. The title compounds were synthesized via the ring opening of N-acylisatin. First, N-acetylisatin was reacted with 4-aminobenzoic acid under conventional heating as well as microwave irradiation to afford 4-(2-(2-acetamidophenyl-2-oxoacetamidobenzoic acid. This α-ketoamide was coupled to different amino acid esters using OxymaPure/DIC as a coupling reagent to afford 4-[2-(2-acetylaminophenyl-2-oxo-acetylamino]benzoyl amino acid ester derivatives in excellent yield and purity. The synthesized compounds were characterized using FT-IR, NMR, and elemental analysis.

  4. Hydrogen peroxide stabilization in one-dimensional flow columns

    Science.gov (United States)

    Schmidt, Jeremy T.; Ahmad, Mushtaque; Teel, Amy L.; Watts, Richard J.

    2011-09-01

    Rapid hydrogen peroxide decomposition is the primary limitation of catalyzed H 2O 2 propagations in situ chemical oxidation (CHP ISCO) remediation of the subsurface. Two stabilizers of hydrogen peroxide, citrate and phytate, were investigated for their effectiveness in one-dimensional columns of iron oxide-coated and manganese oxide-coated sand. Hydrogen peroxide (5%) with and without 25 mM citrate or phytate was applied to the columns and samples were collected at 8 ports spaced 13 cm apart. Citrate was not an effective stabilizer for hydrogen peroxide in iron-coated sand; however, phytate was highly effective, increasing hydrogen peroxide residuals two orders of magnitude over unstabilized hydrogen peroxide. Both citrate and phytate were effective stabilizers for manganese-coated sand, increasing hydrogen peroxide residuals by four-fold over unstabilized hydrogen peroxide. Phytate and citrate did not degrade and were not retarded in the sand columns; furthermore, the addition of the stabilizers increased column flow rates relative to unstabilized columns. These results demonstrate that citrate and phytate are effective stabilizers of hydrogen peroxide under the dynamic conditions of one-dimensional columns, and suggest that citrate and phytate can be added to hydrogen peroxide before injection to the subsurface as an effective means for increasing the radius of influence of CHP ISCO.

  5. Effects of solubilization on the inhibition of the p-type ATPase from maize roots by N-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline.

    Science.gov (United States)

    Brauer, D K; Gurriel, M; Tu, S I

    1992-12-01

    The biochemical events utilized by transport proteins to convert the chemical energy from the hydrolysis of ATP into an electro-chemical gradient are poorly understood. The inhibition of the plasma membrane ATPase from corn (Zea mays L.) roots by N-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline (EEDQ) was compared to that of ATPase solubilized with N-tetradecyl-N,N-dimethyl-3-ammonio-1-propane-sulfonate (3-14) to provide insight into the minimal functional unit. The chromatographic behavior of the 3-14-solubilized ATPase activity during size exclusion chromatography and glycerol gradient centrifugation indicated that the solubilized enzyme was in a monomeric form. Both plasma membrane-bound and solubilized ATPase were inhibited by EEDQ in a time- and concentration-dependent manner consistent with a first-order reaction. When the log of the reciprocal of the half-time for inhibition was plotted as a function of the log of the EEDQ concentration, straight lines were obtained with slopes of approximately 0.5 and 1.0 for membrane-bound and 3-14-solubilized ATPase, respectively, indicating a change in the number of polypeptides per functional ATPase complex induced by solubilization with 3-14.

  6. Synthesis of acrylic prepolymer

    International Nuclear Information System (INIS)

    Hussin bin Mohd Nor; Dahlan bin Haji Mohd; Mohamad Hilmi bin Mahmood.

    1988-04-01

    An acrylic prepolymer was synthesized from glycidyl methacrylate (GMA), butyl methacrylate (BMA), methyl methacrylate (MMA) and acrylic acid (AA). Butyl acetate (BAc), benzoyl peroxide (BzO), 4-methoxyphenol (MPh) and triethylamine (TEA) were used as solvent, initiator, inhibitor and catalyst respectively. Observations of the synthesis leading to the formation of acrylic prepolymer are described. (author)

  7. Ligninolytic enzymes in the coal solubilizing deuteromycetes Trichoderma atroviride and Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Moenkemann, H.; Scheel, T.; Hoelker, U.; Ludwig, S.; Hoefer, M. [Bonn Univ. (Germany). Botanisches Inst.

    1997-12-31

    Evidence is presented for the lignite induced expression of lignin peroxidases, manganese-dependent peroxidases, laccases and glyoxal oxidases in the coal solubilizing fungi Trichoderma atroviride and Fusarium oxysporum under different growth conditions. (orig.)

  8. Rearrangements of organic peroxides and related processes

    Directory of Open Access Journals (Sweden)

    Ivan A. Yaremenko

    2016-08-01

    Full Text Available This review is the first to collate and summarize main data on named and unnamed rearrangement reactions of peroxides. It should be noted, that in the chemistry of peroxides two types of processes are considered under the term rearrangements. These are conventional rearrangements occurring with the retention of the molecular weight and transformations of one of the peroxide moieties after O–O-bond cleavage. Detailed information about the Baeyer−Villiger, Criegee, Hock, Kornblum−DeLaMare, Dakin, Elbs, Schenck, Smith, Wieland, and Story reactions is given. Unnamed rearrangements of organic peroxides and related processes are also analyzed. The rearrangements and related processes of important natural and synthetic peroxides are discussed separately.

  9. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions. Phase 1: Laboratory and pilot field-scale testing. Phase 2: Solubilization test and partitioning interwell tracer tests. Final report

    International Nuclear Information System (INIS)

    1997-01-01

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km 2 in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation

  10. Nanodisc-solubilized membrane protein library reflects the membrane proteome.

    Science.gov (United States)

    Marty, Michael T; Wilcox, Kyle C; Klein, William L; Sligar, Stephen G

    2013-05-01

    The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membrane proteins and have been used to study a wide variety of purified membrane proteins. This report details the incorporation of an unbiased population of membrane proteins from Escherichia coli membranes into Nanodiscs. This solubilized membrane protein library (SMPL) forms a soluble in vitro model of the membrane proteome. Since Nanodiscs contain isolated proteins or small complexes, the SMPL is an ideal platform for interactomics studies and pull-down assays of membrane proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the protein population before and after formation of the Nanodisc library indicates that a large percentage of the proteins are incorporated into the library. Proteomic identification of several prominent bands demonstrates the successful incorporation of outer and inner membrane proteins into the Nanodisc library.

  11. Protein oxidation and peroxidation

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan

    2016-01-01

    Proteins are major targets for radicals and two-electron oxidants in biological systems due to their abundance and high rate constants for reaction. With highly reactive radicals damage occurs at multiple side-chain and backbone sites. Less reactive species show greater selectivity with regard...... to the residues targeted and their spatial location. Modification can result in increased side-chain hydrophilicity, side-chain and backbone fragmentation, aggregation via covalent cross-linking or hydrophobic interactions, protein unfolding and altered conformation, altered interactions with biological partners...... and modified turnover. In the presence of O2, high yields of peroxyl radicals and peroxides (protein peroxidation) are formed; the latter account for up to 70% of the initial oxidant flux. Protein peroxides can oxidize both proteins and other targets. One-electron reduction results in additional radicals...

  12. An update on the management of acne vulgaris

    Directory of Open Access Journals (Sweden)

    Jonette Keri

    2009-06-01

    Full Text Available Jonette Keri1,2, Michael Shiman11Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, FL, USA; 2Dermatology Service, Miami VA Hospital, FL, USAAbstract: Acne vulgaris is a common skin disorder that can affect individuals from childhood to adulthood, most often occurring in the teenage years. Acne can have a significant physical, emotional, and social impact on an individual. Many different treatment options are available for the treatment of acne vulgaris. Commonly used topical treatments include benzoyl peroxide, antibiotics, sulfur and sodium sulfacetamide, azelaic acid, and retinoids. Systemic treatment is frequently used and includes the use of systemic antibiotics, oral contraceptives, antiandrogens, and retinoids. Other treatment modalities exist such as the use of superficial chemical peels as well as using laser and light devices for the treatment of acne. With the multitude of treatment options and the rapidly expanding newer technologies available to clinicians, it is important to review and be aware of the current literature and studies regarding the treatment of acne vulgaris.Keywords: acne vulgaris, treatment, benzoyl peroxide, antibiotics, retinoids, lasers

  13. Task-specific ionic liquids for solubilizing metal compounds

    OpenAIRE

    Thijs, Ben

    2007-01-01

    The main goal of this PhD thesis was to design new task-specific ionic liquids with the ability to dissolve metal compounds. Despite the large quantity of papers published on ionic liquids, not much is known about the mechanisms of dissolving metals in ionic liquids or about metal-containing ionic liquids. Additionally, many of the commercially available ionic liquids exhibit a very limited solubilizing power for metal compounds, although this is for many applications like electrodeposition a...

  14. Response surface methodology for the optimization of sludge solubilization by ultrasonic pre-treatment

    Science.gov (United States)

    Zheng, Mingyue; Zhang, Xiaohui; Lu, Peng; Cao, Qiguang; Yuan, Yuan; Yue, Mingxing; Fu, Yiwei; Wu, Libin

    2018-02-01

    The present study examines the optimization of the ultrasonic pre-treatment conditions with response surface experimental design in terms of sludge disintegration efficiency (solubilisation of organic components). Ultrasonic pre-treatment for the maximum solubilization with residual sludge enhanced the SCOD release. Optimization of the ultrasonic pre-treatment was conducted through a Box-Behnken design (three variables, a total of 17 experiments) to determine the effects of three independent variables (power, residence time and TS) on COD solubilization of sludge. The optimal COD was obtained at 17349.4mg/L, when the power was 534.67W, the time was 10.77, and TS was 2%, while the SE of this condition was 28792J/kg TS.

  15. Solid substrate fermentation of lignite by the coal-solubilizing mould, Trichoderma atroviride, in a new type of bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Holker, U.; Hofer, M. [University of Bonn, Bonn (Germany)

    2002-07-01

    Trichoderma atroviride CBS 349 is able to solubilize lignite. The mould was cultured under non-sterile conditions in a new type of bioreactor for solid substrate fermentation. German lignite (lithotype A, Bergheim) was used as complex solid substrate. Over 40 days 140 g of 1.5 kg lignite held in a 25 1-bioreactor was solubilized by the fungus.

  16. Influence of biochar application on potassium-solubilizing Bacillus mucilaginosus as potential biofertilizer.

    Science.gov (United States)

    Liu, Sainan; Tang, Wenzhu; Yang, Fan; Meng, Jun; Chen, Wenfu; Li, Xianzhen

    2017-01-02

    Biochar can enhance soil fertility to increase agricultural productivity, whereas its improvement in soil microbial activity is still unclear. In this article, the influence of biochar on the cell growth and the potassium-solubilizing activity of Bacillus mucilaginosus AS1153 was examined. The impact on cell growth is related to the biochar-derived feedstocks and the particle size of biochar. Both intrinsic features and inner component fraction can promote the cell growth of B. mucilaginosus AS1153. The potassium-solubilizing activity was increased by 80% when B. mucilaginosus was incubated in conjunction with the biochar derived from corn stover. The survival time of B. mucilaginosus also was prolonged by adsorption in biochar. The experimental results suggested that the biochar containing B. mucilaginosus could be used as a potential biofertilizer to sustain crop production.

  17. Impact of phosphate-solubilizing bacteria inoculation methods on phosphorus transformation and long-term utilization in composting.

    Science.gov (United States)

    Wei, Yuquan; Zhao, Yue; Fan, Yuying; Lu, Qian; Li, Mingxiao; Wei, Qingbin; Zhao, Yi; Cao, Zhenyu; Wei, Zimin

    2017-10-01

    This study aimed to assess the effect of phosphate-solubilizing bacteria (PSB) application and inoculation methods on rock phosphate (RP) solubilization and bacterial community during composting. The results showed that PSB inoculation in different stages of composting, especially both in the beginning and cooling stages, not only improved the diversity and abundance of PSB and bacterial community, but also distinctly increased the content of potential available phosphorus. Redundancy analysis indicated that the combined inoculation of PSB in the initial stage with higher inoculation amount and in the cooling stage with lower inoculation amount was the best way to improve the inoculation effect and increase the solubilization and utilization of RP during composting. Besides, we suggested three methods to improve phosphorus transformation and long-term utilization efficiency in composts based on biological fixation of phosphates by humic substance and phosphate-accumulating organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Fatty acid solubilizer from the oral disk of the blowfly.

    Directory of Open Access Journals (Sweden)

    Yuko Ishida

    Full Text Available Blowflies are economic pests of the wool industry and potential vectors for epidemics. The establishment of a pesticide-free, environmentally friendly blowfly control strategy is necessary. Blowflies must feed on meat in order to initiate the cascade of events that are involved in reproduction including juvenile hormone synthesis, vitellogenesis, and mating. During feeding blowflies regurgitate salivary lipase, which may play a role in releasing fatty acids from triglycerides that are found in food. However, long-chain fatty acids show low solubility in aqueous solutions. In order to solubilize and ingest the released hydrophobic fatty acids, the blowflies must use a solubilizer.We applied native PAGE, Edman degradation, cDNA cloning, and RT-PCR to characterize a protein that accumulated in the oral disk of the black blowfly, Phormia regina. In situ hybridization was carried out to localize the expression at the cellular level. A fluorescence competitive binding assay was used to identify potential ligands of this protein.A protein newly identified from P. regina (PregOBP56a belonged to the classic odorant-binding protein (OBP family. This gene was expressed in a cluster of cells that was localized between pseudotracheae on the oral disk, which are not accessory cells of the taste peg chemosensory sensilla that normally synthesize OBPs. At pH 7 and pH 6, PregOBP56a bound palmitic, stearic, oleic, and linoleic acids, that are mainly found in chicken meat. The binding affinity of PregOBP56a decreased at pH 5. We propose that PregOBP56a is a protein that solubilizes fatty acids during feeding and subsequently helps to deliver the fatty acids to the midgut where it may help in the process of reproduction. As such, PregOBP56a is a potential molecular target for controlling the blowfly.

  19. [Filamentous and phosphate solubilizing fungi relationships with some edaphic parameters and coffee plantations management].

    Science.gov (United States)

    Posada, Raúl Hernando; Sánchez de Prager, Marina; Sieverding, Ewald; Aguilar Dorantes, Karla; Heredia-Abarca, Gabriela Patricia

    2012-09-01

    Soil properties and the environment have multiple outcomes on fungal communities. Although, the interaction effects between management intensity, pH, available phosphorus, organic carbon, soil texture and different fractions of water stable macro-aggregates on the communities of microscopic filamentous fungi (MFF), iron phosphate solubilizing fungi (PSF-Fe), and iron and calcium phosphate solubilizing fungi (PSF-(Fe+Ca)), have been previously evaluated in field conditions, this has never been performed in terms of their combined effects, neither with phosphate solubilizing fungi. To assess this, we collected 40 composite soil samples from eight Mexican and Colombian coffee plantations, with different management intensities and physico-chemical edaphic parameters, during 2008-2009. We isolated different communities of MFF, PSF-Fe and PSF-(Fe+Ca), by wet sieving and soil particles culture in Potato-Dextrose-Agar from soil samples, and we classified isolates in terms of their phosphate solubilizing ability. Following the principal component analysis results, we decided to analyze fungal communities and abiotic factors interactions for each country separately. Structural Equation Models revealed that organic carbon was positively associated to MFF richness and number of isolates (lambda>0.58), but its relationship with PSF-Fe and PSF-(Fe+Ca) were variable; while the available phosphorus, pH and water stable macro-aggregate fractions did not show a clear pattern. Management intensity was negatively related to PSF-Fe (lambda coffee plantations. We found that the relationships of clay and organic carbon content, and available phosphorus and soil pH, with the species richness and number of isolates of MFF, PSF-Fe and PSF-(Fe+Ca) were highly variable; this made impossible to generalize the responses between saprotrophic fungal groups and geographic zones. The management intensity was not related to species richness and number of isolates of MFF in any coffee areas, while

  20. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions: Phase 1 -- Laboratory and pilot field-scale testing and Phase 2 -- Solubilization test and partitioning and interwell tracer tests. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-24

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km{sup 2} in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation.

  1. Redox Polymerization of Methyl Methacrylate in the Fluorous Triphasic System

    Institute of Scientific and Technical Information of China (English)

    Shi Zhen CHEN; Yun Peng BAI; Zhao Long LI

    2006-01-01

    Methyl methacrylate (MMA) was polymerized by using of benzoyl peroxide (BPO) and N, N-dimethylaniline (DMA) as an redox initiator in fluorous triphasic system at room temperature.The polymerization was occurred in both initiator layer and monomer layer in a U-tube. It was found that PMMA obtained from the initiator layer with relatively narrow polydispersity.(PDI =1.38)

  2. Kinetics of Platinum-Catalyzed Decomposition of Hydrogen Peroxide

    Science.gov (United States)

    Vetter, Tiffany A.; Colombo, D. Philip, Jr.

    2003-07-01

    CIBA Vision Corporation markets a contact lens cleaning system that consists of an AOSEPT disinfectant solution and an AOSEPT lens cup. The disinfectant is a buffered 3.0% m/v hydrogen peroxide solution and the cup includes a platinum-coated AOSEPT disc. The hydrogen peroxide disinfects by killing bacteria, fungi, and viruses found on the contact lenses. Because the concentration of hydrogen peroxide needed to disinfect is irritating to eyes, the hydrogen peroxide needs to be neutralized, or decomposed, before the contact lenses can be used again. A general chemistry experiment is described where the kinetics of the catalyzed decomposition of the hydrogen peroxide are studied by measuring the amount of oxygen generated as a function of time. The order of the reaction with respect to the hydrogen peroxide, the rate constant, and the energy of activation are determined. The integrated rate law is used to determine the time required to decompose the hydrogen peroxide to a concentration that is safe for eyes.

  3. High temperature chemically resistant polymer concrete

    Science.gov (United States)

    Sugama, T.; Kukacka, L.E.

    High temperature chemically resistant, non-aqueous polymer concrete composites consist of about 12 to 20% by weight of a water-insoluble polymer binder. The binder is polymerized in situ from a liquid vinyl-type monomer or mixture of vinyl containing monomers such as triallylcyanurate, styrene, acrylonitrile, acrylamide, methacrylamide, methyl-methacrylate, trimethylolpropane trimethacrylate and divinyl benzene. About 5 to 40% by weight of a reactive inorganic filler selected from the group consisting of tricalcium silicate and dicalcium silicate and mixtures containing less than 2% free lime, and about 48 to 83% by weight of silica sand/ and a free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, other orgaic peroxides and combinations to initiate polymerization of the monomer in the presence of the inorganic filers are used.

  4. Hydrogen Peroxide Probes Directed to Different Cellular Compartments

    Science.gov (United States)

    Malinouski, Mikalai; Zhou, You; Belousov, Vsevolod V.; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2011-01-01

    Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events. Conclusions We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells. PMID:21283738

  5. Hydrogen peroxide probes directed to different cellular compartments.

    Directory of Open Access Journals (Sweden)

    Mikalai Malinouski

    2011-01-01

    Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

  6. Solubilization of trace organics in block copolymer micelles for environmental separation using membrane extraction principles

    Energy Technology Data Exchange (ETDEWEB)

    Hatton, T.A.

    1992-12-01

    The solubilization of a range of polycyclic aromatic hydrocarbons in block copolymer micelles has been studied as a function of polymer composition, architecture, and temperature. Micelle formation is favored at high temperatures, leading to significant enhancements in solubilization capacity. At low temperatures, however, micelles do not form and the solubilization capacity of the block copolymer solution for the organics is low; this provides a convenient method for the regeneration of micellar solutions used as solvents'' in the treatment of contaminated feed streams using membrane extraction principles. It has also been shown (in collaboration with K.P. Johnston of University of Texas, Austin) that supercritical CO[sub 2] can be used effectively for micelle regeneration. Theoretical calculations of the structure of block copolymer micelles in the presence and absence of solutes using self-consistent mean-field lattice theories have successfully captured the trends observed with changing polymer composition and architecture, often quantitatively. The temperature and composition dependence of the micellar properties were determined by allowing the individual polymer segments to assume both polar and non-polar conformations.

  7. Nanodisc-solubilized membrane protein library reflects the membrane proteome

    OpenAIRE

    Marty, Michael T.; Wilcox, Kyle C.; Klein, William L.; Sligar, Stephen G.

    2013-01-01

    The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membr...

  8. Solubilization of myofibrillar proteins in water or low ionic strength media: Classical techniques, basic principles, and novel functionalities.

    Science.gov (United States)

    Chen, Xing; Tume, Ron K; Xu, Xinglian; Zhou, Guanghong

    2017-10-13

    The qualitative characteristics of meat products are closely related to the functionality of muscle proteins. Myofibrillar proteins (MPs), comprising approximately 50% of total muscle proteins, are generally considered to be insoluble in solutions of low ionic strength ( 0.3 M) for solubilization. These soluble proteins are the ones which determine many functional properties of meat products, including emulsification and thermal gelation. In order to increase the utilization of meat and meat products, many studies have investigated the solubilization of MPs in water or low ionic strength media and determining their functionality. However, there still remains a lack of systematic information on the functional properties of MPs solubilized in this manner. Hence, this review will explore some typical techniques that have been used. The main procedures used for their solubilization, the fundamental principles and their functionalities in water (low ionic strength medium) are comprehensively discussed. In addition, advantages and disadvantages of each technique are summarized. Finally, future considerations are presented to facilitate progress in this new area and to enable water soluble muscle MPs to be utilized as novel meat ingredients in the food industry.

  9. Initial pH of medium affects organic acids production but do not affect phosphate solubilization.

    Science.gov (United States)

    Marra, Leandro M; de Oliveira-Longatti, Silvia M; Soares, Cláudio R F S; de Lima, José M; Olivares, Fabio L; Moreira, Fatima M S

    2015-06-01

    The pH of the culture medium directly influences the growth of microorganisms and the chemical processes that they perform. The aim of this study was to assess the influence of the initial pH of the culture medium on the production of 11 low-molecular-weight organic acids and on the solubilization of calcium phosphate by bacteria in growth medium (NBRIP). The following strains isolated from cowpea nodules were studied: UFLA03-08 (Rhizobium tropici), UFLA03-09 (Acinetobacter sp.), UFLA03-10 (Paenibacillus kribbensis), UFLA03-106 (Paenibacillus kribbensis) and UFLA03-116 (Paenibacillus sp.). The strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 solubilized Ca3(PO4)2 in liquid medium regardless of the initial pH, although without a significant difference between the treatments. The production of organic acids by these strains was assessed for all of the initial pH values investigated, and differences between the treatments were observed. Strains UFLA03-09 and UFLA03-10 produced the same acids at different initial pH values in the culture medium. There was no correlation between phosphorus solubilized from Ca3(PO4)2 in NBRIP liquid medium and the concentration of total organic acids at the different initial pH values. Therefore, the initial pH of the culture medium influences the production of organic acids by the strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 but it does not affect calcium phosphate solubilization.

  10. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-component DNAPLS with surfactant solutions. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Laboratory studies were conducted at the State University of New York at Buffalo (SUNY) while numerical simulation and field work were undertaken by INTERA Inc. in collaboration with Martin Marietta Energy Systems Inc. at the Paducah Gaseous Diffusion Plant (PGDP) in Kentucky. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). Ten of these were capable of solubilizing TCE to concentrations greater than 15,000 mg/L, compared to its aqueous solubility of 1,100 mg/L. Four surfactants were identified as good solubilizers of all three chlorinated solvents. Of these, a secondary alcohol ethoxylate was the first choice for in situ testing because of its excellent solubilizing ability and its low propensity to sorb. However, this surfactant did not meet the Commonwealth of Kentucky`s acceptance criteria. Consequently, it was decided to use a surfactant approved for use by the Food and Drug Administration as a food-grade additive. As a 1% micellar-surfactant solution, this sorbitan monooleate has a solubilization capacity of 16,000 mg TCE/L, but has a higher propensity to sorb to clays than has the alcohol ethoxylate.

  11. Hydrogen peroxide treatment of TCE contaminated soil

    International Nuclear Information System (INIS)

    Hurst, D.H.; Robinson, K.G.; Siegrist, R.L.

    1993-01-01

    Solvent contaminated soils are ubiquitous in the industrial world and represent a significant environmental hazard due to their persistence and potentially negative impacts on human health and the environment. Environmental regulations favor treatment of soils with options which reduce the volume and toxicity of contaminants in place. One such treatment option is the in-situ application of hydrogen peroxide to soils contaminated with chlorinated solvents such as trichloroethylene (TCE). This study investigated hydrogen peroxide mass loading rates on removal of TCE from soils of varying organic matter content. Batch experiments conducted on contaminated loam samples using GC headspace analysis showed up to 80% TCE removal upon peroxide treatment. Column experiments conducted on sandy loam soils with high organic matter content showed only 25% TCE removal, even at hydrogen peroxide additions of 25 g peroxide per kg soil

  12. Massilia phosphatilytica sp. nov., a phosphate solubilizing bacteria isolated from a long-term fertilized soil

    DEFF Research Database (Denmark)

    Zheng, Bang Xiao; Bi, Qing Fang; Hao, Xiuli

    2017-01-01

    A Gram-stain-negative and rod-shaped bacterial strain, 12-OD1T, with rock phosphate solubilizing ability was isolated from agricultural soil in Hailun, Heilongjiang, PR China. The isolate was affiliated to the genus Massilia, based on 16S rRNA gene sequence alignments, having the highest similari......A Gram-stain-negative and rod-shaped bacterial strain, 12-OD1T, with rock phosphate solubilizing ability was isolated from agricultural soil in Hailun, Heilongjiang, PR China. The isolate was affiliated to the genus Massilia, based on 16S rRNA gene sequence alignments, having the highest...

  13. Quantum-chemical evaluation of the lability of π-electronic systems in N-benzoyl derivatives of phosphorus and sulfur imines

    International Nuclear Information System (INIS)

    Egorov, Yu.P.; Pen'kovskii, V.V.; Boldeskul, I.E.

    1986-01-01

    The charges on atoms, the bond indices, their components, and the energies of the highest occupied π orbitals of four N-benzoyl derivatives of phosphorus and sulfur imines have been calculated by the CNDO/2 method in an spd basis. According to the results obtained, the π system of a bridging sulfur-nitrogen group is more labile than a phosphorus-nitrogen group, in agreement with the experimental evaluations of the transmission of the electronic effects of substituents in these systems. An interpretation of this lability has been given

  14. Maximizing mutagenesis with solubilized CRISPR-Cas9 ribonucleoprotein complexes.

    Science.gov (United States)

    Burger, Alexa; Lindsay, Helen; Felker, Anastasia; Hess, Christopher; Anders, Carolin; Chiavacci, Elena; Zaugg, Jonas; Weber, Lukas M; Catena, Raul; Jinek, Martin; Robinson, Mark D; Mosimann, Christian

    2016-06-01

    CRISPR-Cas9 enables efficient sequence-specific mutagenesis for creating somatic or germline mutants of model organisms. Key constraints in vivo remain the expression and delivery of active Cas9-sgRNA ribonucleoprotein complexes (RNPs) with minimal toxicity, variable mutagenesis efficiencies depending on targeting sequence, and high mutation mosaicism. Here, we apply in vitro assembled, fluorescent Cas9-sgRNA RNPs in solubilizing salt solution to achieve maximal mutagenesis efficiency in zebrafish embryos. MiSeq-based sequence analysis of targeted loci in individual embryos using CrispRVariants, a customized software tool for mutagenesis quantification and visualization, reveals efficient bi-allelic mutagenesis that reaches saturation at several tested gene loci. Such virtually complete mutagenesis exposes loss-of-function phenotypes for candidate genes in somatic mutant embryos for subsequent generation of stable germline mutants. We further show that targeting of non-coding elements in gene regulatory regions using saturating mutagenesis uncovers functional control elements in transgenic reporters and endogenous genes in injected embryos. Our results establish that optimally solubilized, in vitro assembled fluorescent Cas9-sgRNA RNPs provide a reproducible reagent for direct and scalable loss-of-function studies and applications beyond zebrafish experiments that require maximal DNA cutting efficiency in vivo. © 2016. Published by The Company of Biologists Ltd.

  15. Synthesis of new derivatives of 1-(3-aminophenyl-4-benzoyl-5-phenyl-1H-pyrazole-3-carboxylic acid

    Directory of Open Access Journals (Sweden)

    RAHMI KASIMOGULLAR

    2010-12-01

    Full Text Available 1-(3-Aminophenyl-4-benzoyl-5-phenyl-1H-pyrazole-3-carboxylic acid (1 was synthesized according to the literature. 2-(3-Aminophenyl-2,6-dihydro-3,4-diphenyl-7H-pyrazolo[3,4-d]pyridazin-7-one (5 was obtained by the cyclocondensation reaction of 1 with hydrazine hydrate. New pyrazole derivatives of compounds 1 and 5 were synthesized by their reaction with β-diketones, β-ketoesters, β-naphthol, phenol and various other reagents. The structures of the synthesized compounds were characterized by 1H-NMR, 13C-NMR, IR and mass spectroscopy, as well as elemental analysis.

  16. Phosphate Solubilizing Bacteria Adaptive to Vinasse

    Directory of Open Access Journals (Sweden)

    Kahar Muzakhar

    2015-06-01

    Full Text Available Microorganisms identified as phosphate solubilizing bacteria (PSB adaptive to vinasse were successfully screened from sugarcane soil from an agriculatural estate in Jatiroto. By conducting a screening on Pikovskaya’s agar medium (PAM, we found that five different isolates were detected as PSB (pvk-5a, pvk-5b, pvk-6b, pvk-7a, and pvk-8a. Of the five isolates only three could be grown and were found to be adaptive to vinasse based medium without any nutrients added (pvk-5a, pvk-5b and pvk-7a. The three isolates were characterized as coccus and Gram negative with no endospores detected. We suggest that these three isolates can be used as biofertilizer agent to support organic farming.

  17. Effect of antioxidants and silicates on peroxides in povidone.

    Science.gov (United States)

    Narang, Ajit S; Rao, Venkatramana M; Desai, Divyakant S

    2012-01-01

    Reactive peroxides in povidone often lead to degradation of oxidation-labile drugs. To reduce peroxide concentration in povidone, the roles of storage conditions, antioxidants, and silicates were investigated. Povidone alone and its physical mixtures with ascorbic acid, propyl gallate, sodium sulfite, butylated hydroxyanisole (BHA), or butylated hydroxytoluene (BHT) were stored at 25 °C and 40 °C, at 11%, 32%, and 50% relative humidity. In addition, povidone solution in methanol was equilibrated with silicates (silica gel and molecular sieves), followed by solvent evaporation to recover povidone powder. Peroxide concentrations in povidone were measured. The concentration of peroxides in povidone increased under very-low-humidity storage conditions. Among the antioxidants, ascorbic acid, propyl gallate, and sodium sulfite reduced the peroxide concentration in povidone, whereas BHA and BHT did not. Water solubility appeared to determine the effectiveness of antioxidants. Also, some silicates significantly reduced peroxide concentration in povidone without affecting its functionality as a tablet binder. Porosity of silicates was critical to their ability to reduce the peroxide concentration in povidone. A combination of these approaches can reduce the initial peroxide concentration in povidone and minimize peroxide growth under routine storage conditions. Copyright © 2011 Wiley-Liss, Inc.

  18. Determination of hydrogen peroxide in water by chemiluminescence detection, (1). Flow injection type hydrogen peroxide detection system

    International Nuclear Information System (INIS)

    Yamashiro, Naoya; Uchida, Shunsuke; Satoh, Yoshiyuki; Morishima, Yusuke; Yokoyama, Hiroaki; Satoh, Tomonori; Sugama, Junichi; Yamada, Rie

    2004-01-01

    A flow injection type hydrogen peroxide detection system with a sub-ppb detection limit has been developed to determine hydrogen peroxide concentration in water sampled from a high temperature, high pressure hydrogen peroxide water loop. The hydrogen peroxide detector is based on luminol chemiluminescence spectroscopy. A small amount of sample water (20 μl) is mixed with a reagent mixture, an aqueous solution of luminol and Co 2+ catalyst, in a mixing cell which is installed just upstream from the detection cell. The optimum values for pH and the concentrations of luminol and Co 2+ ion have been determined to ensure a lower detectable limit and a higher reproducibility. The photocurrent detected by the detection system is expressed by a linear function of the hydrogen peroxide concentration in the region of lower concentration ([H 2 O 2 ] 2 O 2 ] in the region of higher concentration ([H 2 O 2 ] > 10 ppb). The luminous intensity of luminol chemiluminescence is the highest when pH of the reagent mixture is 11.0. Optimization of the major parameters gives the lowest detectable limit of 0.3 ppb. (author)

  19. Solubilization and molecular size of atrial natriuretic hormone (ANH) receptors from rabbit aorta, renal cortex and adrenal

    International Nuclear Information System (INIS)

    Budzik, G.P.; Bush, E.N.; Holleman, W.H.

    1986-01-01

    ANH(1-28) is presumed to regulate blood pressure and fluid balance via membrane receptors coupled to particulate guanylate cyclase. ANH receptors were solubilized from rabbit aorta, renal cortex and adrenal, primary ANH targets. Plasma membranes extracted with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate(CHAPS) yield solubilized receptors with high affinity binding of 125 I-Tyr 28 -ANH. Degradation of hormone was minimized with a broad spectrum of protease inhibitors. 125 I-ANH binding reached maximum by 1 hr at 0 0 C and was stable for at least an additional 2 hrs. Bound was separated from free ligand by HPLC gel filtration on TSK-3000SW in PBS/CHAPS. Bound hormone eluted at a MW of ∼ 200KD in each tissue preparation and was displaced by unlabelled ANH. The concentration of solubilized binding sites was proportional to densities in intact plasma membranes, i.e., adrenal > renal > aorta. Following separation of free hormone, 125 I-ANH-receptors complexes were coupled using bifunctional crosslinking reagents. SDS-PAGE analysis and autoradiography indicated a major labelled band at ∼ 150KD in each tissue preparation. The mobility of this labelled band was not sensitive to reduction before SDS-PAGE. Although these results suggest that solubilized ANH receptors from primary target tissues are very similar, microheterogeneity affecting binding affinity or signal transduction cannot as yet be excluded

  20. HemX is required for production of 2-ketogluconate, the predominant organic anion required for inorganic phosphate solubilization by Burkholderia sp. Ha185.

    Science.gov (United States)

    Hsu, Pei-Chun Lisa; Condron, Leo; O'Callaghan, Maureen; Hurst, Mark R H

    2015-12-01

    The bacterium Burkholderia sp. Ha185 readily solubilizes inorganic phosphate by releasing the low molecular weight organic anion, 2-ketogluconate. Using random transposon mutagenesis and in silico analysis, a mutation that caused almost complete abolition of phosphate solubilization was located within hemX, which is part of the hem operon. Burkholderia sp. Ha185 HemX is a multidomain protein, predicted to encode a bifunctional uroporphyrinogen-III synthetase/uroporphyrin-III C-methyltransferase, which has not previously been implicated in phosphate solubilization. Complementation of hemX restored the ability of the mutant to solubilize phosphate in both plate and liquid cultures. Based on a combination of organic-anion profiling, quantitative polymerase chain reaction and in silico analyses, hemX was confirmed to be solely responsible for hydroxyapatite solubilization in Burkholderia sp. Ha185. It is proposed that the biosynthesis of a yet to be determined redox cofactor by HemX is the main pathway for generating 2-ketogluconate via a haem-dependent gluconate 2-dehydrogenase in Burkholderia sp. Ha185. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. Photoacoustic analysis of the solubilization kinetics of pulmonary secretions from cystic fibrosis patients - secretor and non-secretor phenotypes

    Energy Technology Data Exchange (ETDEWEB)

    Barja, P R; Coelho, C C; Paiva, R F [Research and Development Institute, UNIVAP, Av. Shishima Hifumi 2911, Sao Jose dos Campos, SP (Brazil); Barboza, M A; Matos, L C; Matos, C C B [Faculty of Medicine of Sao Jose do Rio Preto (FAMERP), Sao Jose do Rio Preto, SP (Brazil); Oliveira, L V F, E-mail: barja@univap.b [Rehabilitation Sciences Master' s Program, Nove de Julho University (UNINOVE), Sao Paulo, SP (Brazil)

    2010-03-01

    Cystic fibrosis (CF) is an autosomal recessive inherited disease that increases viscoelasticity of pulmonary secretions. Affected patients are required to use therapeutic aerosols continuously. The expression of ABH glycoconjugates in exocrine secretions determines the nature of part of the carbohydrates present in these secretions, allowing the classification of individuals into the so-called 'secretor' and 'non secretor' phenotypes. The aim of this work was to employ photoacoustic (PA) measurements to monitor the solubilization kinetics of pulmonary secretions from CF patients, analyzing the influence of the secretor status in the solubilization kinetics of samples nebulized with different therapeutic aerosols. Sputum samples were obtained by spontaneous expectoration from positive and negative secretor CF patients. Each sample was nebulized with i) tobramycin, ii) alpha dornase, and iii) N-acetylcysteine in a PA cell; fitting of the data with the Boltzmann equation led to the determination of t{sub 0} (typical interaction time) and {Delta}t (solubilization interval) for each curve. Differences between the secretor and non-secretor phenotypes were statistically significant in the groups for tobramycin and alpha dornase, but not for N-acetylcysteine. Results show that the secretor status influences the solubilization of pulmonary mucus of CF patients nebulized with tobramycin and alpha dornase.

  2. Effect of cholesterol nucleation-promoting activity on cholesterol solubilization in model bile

    NARCIS (Netherlands)

    Groen, A. K.; Ottenhoff, R.; Jansen, P. L.; van Marle, J.; Tytgat, G. N.

    1989-01-01

    Human bile contains a factor with cholesterol nucleation-promoting activity that binds to concanavalin A-Sepharose. In this study we have investigated the effect of this activity on the dynamics of lipid solubilization in supersaturated model bile. A concanavalin A binding protein fraction of human

  3. Modified denatured lysozyme effectively solubilizes fullerene c60 nanoparticles in water

    Science.gov (United States)

    Siepi, Marialuisa; Politi, Jane; Dardano, Principia; Amoresano, Angela; De Stefano, Luca; Monti, Daria Maria; Notomista, Eugenio

    2017-08-01

    Fullerenes, allotropic forms of carbon, have very interesting pharmacological effects and engineering applications. However, a very low solubility both in organic solvents and water hinders their use. Fullerene C60, the most studied among fullerenes, can be dissolved in water only in the form of nanoparticles of variable dimensions and limited stability. Here the effect on the production of C60 nanoparticles by a native and denatured hen egg white lysozyme, a highly basic protein, has been systematically studied. In order to obtain a denatured, yet soluble, lysozyme derivative, the four disulfides of the native protein were reduced and exposed cysteines were alkylated by 3-bromopropylamine, thus introducing eight additional positive charges. The C60 solubilizing properties of the modified denatured lysozyme proved to be superior to those of the native protein, allowing the preparation of biocompatible highly homogeneous and stable C60 nanoparticles using lower amounts of protein, as demonstrated by dynamic light scattering, transmission electron microscopy and atomic force microscopy studies. This lysozyme derivative could represent an effective tool for the solubilization of other carbon allotropes.

  4. Radiation-induced peroxidation of egg lecithin liposomes

    International Nuclear Information System (INIS)

    Bisby, R.H.; Cundall, R.B.; Tomaszewski, K.E.; Coleman, M.H.; Gould, G.

    1983-01-01

    Peroxidation of multilamellar vesicles of egg lecithin was measured following γ-irradiation of oxygen saturated suspensions. The addition of hydroxyl radical scavengers and the enzymes superoxide dismutase and catalase was used to show that hydroxyl radicals were the major species initiating peroxidation. Superoxide radicals were found to be much less effective initiators of peroxidation. Trolox C, a water soluble analogue of vitamin E, was found to act as an efficient antioxidant in this system. (author)

  5. 7 CFR 58.431 - Hydrogen peroxide.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Hydrogen peroxide. 58.431 Section 58.431 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.431 Hydrogen peroxide. The solution shall comply with the specification of the U.S...

  6. Phosphate solubilization and acid phosphatase activity of Serratia sp. isolated from mangrove soil of Mahanadi river delta, Odisha, India

    Directory of Open Access Journals (Sweden)

    B.C. Behera

    2017-06-01

    Full Text Available Phosphorus is an essential element for all life forms. Phosphate solubilizing bacteria are capable of converting phosphate into a bioavailable form through solubilization and mineralization processes. Hence in the present study a phosphate solubilizing bacterium, PSB-37, was isolated from mangrove soil of the Mahanadi river delta using NBRIP-agar and NBRIP-BPB broth containing tricalcium phosphate as the phosphate source. Based on phenotypic and molecular characterization, the strain was identified as Serratia sp. The maximum phosphate solubilizing activity of the strain was determined to be 44.84 μg/ml, accompanied by a decrease in pH of the growth medium from 7.0 to 3.15. During phosphate solubilization, various organic acids, such as malic acid (237 mg/l, lactic acid (599.5 mg/l and acetic acid (5.0 mg/l were also detected in the broth culture through HPLC analysis. Acid phosphatase activity was determined by performing p-nitrophenyl phosphate assay (pNPP of the bacterial broth culture. Optimum acid phosphatase activity was observed at 48 h of incubation (76.808 U/ml, temperature of 45 °C (77.87 U/ml, an agitation rate of 100 rpm (80.40 U/ml, pH 5.0 (80.66 U/ml and with glucose as a original carbon source (80.6 U/ml and ammonium sulphate as a original nitrogen source (80.92 U/ml. Characterization of the partially purified acid phosphatase showed maximum activity at pH 5.0 (85.6 U/ml, temperature of 45 °C (97.87 U/ml and substrate concentration of 2.5 mg/ml (92.7 U/ml. Hence the present phosphate solubilizing and acid phosphatase production activity of the bacterium may have probable use for future industrial, agricultural and biotechnological application.

  7. Assessment of two carrier materials for phosphate solubilizing biofertilizers and their effect on growth of wheat (Triticum aestivum L.).

    Science.gov (United States)

    Mukhtar, Salma; Shahid, Izzah; Mehnaz, Samina; Malik, Kauser A

    2017-12-01

    Biofertilizers are usually carrier-based inoculants containing beneficial microorganisms. Incorporation of microorganisms in carrier material enables easy-handling, long-term storage and high effectiveness of biofertilizers. Objective of the present study was to assess enriched biogas sludge and soil as biofertilizer carriers on growth and yield of wheat. Six phosphate solubilizing strains were used in this study. Three phosphate solubilizing strains, 77-NS2 (Bacillus endophyticus), 77-CS-S1 (Bacillus sphaericus) and 77-NS5 (Enterobacter aerogenes) were isolated from the rhizosphere of sugarcane, two strains, PSB5 (Bacillus safensis) and PSB12 (Bacillus megaterium) from the rhizosphere of wheat and one halophilic phosphate solubilizing strain AT2RP3 (Virgibacillus sp.) from the rhizosphere of Atriplex amnicola, were used as bioinoculants. Phosphate solubilization ability of these strains was checked in vitro in Pikovskaya medium, containing rock phosphate (RP) as insoluble P source, individually supplemented with three different carbon sources, i.e., glucose, sucrose and maltose. Maximum phosphate solubilization; 305.6μg/ml, 217.2μg/ml and 148.1μg/ml was observed in Bacillus strain PSB12 in Pikovskaya medium containing sucrose, maltose and glucose respectively. A field experiment and pot experiments in climate control room were conducted to study the effects of biogas sludge and enriched soil based phosphorous biofertilizers on growth of wheat. Bacillus strain PSB12 significantly increased root and shoot dry weights and lengths using biogas sludge as carrier material in climate control room experiments. While in field conditions, significant increase in root and shoot dry weights, lengths and seed weights was seen by PSB12 and PSB5 (Bacillus) and Enterobacter strain 77-NS5 using biogas sludge as carrier. PSB12 also significantly increased both root and shoot dry weights and lengths in field conditions when used as enriched soil based inoculum. These results

  8. Phosphorus Solubilizing and Releasing Bacteria Screening from the Rhizosphere in a Natural Wetland

    Directory of Open Access Journals (Sweden)

    Ying Cao

    2018-02-01

    Full Text Available Inorganic phosphorus (P-solubilizing bacteria (IPSB and organic P-mineralizing bacteria (OPMB were isolated from bacteria that were first extracted from the rhizosphere soil of a natural wetland and then grown on either tricalcium phosphate or lecithin medium. The solubilizing of inorganic P was the major contribution to P availability, since the isolated bacteria released much more available P from inorganic tricalcium phosphate than lecithin. IPSB No. 5 had the highest P release rate, that is, 0.53 mg·L−1·h−1 in 96 h, and R10′s release rate was 0.52 mg·L−1·h−1 in 10 days. The bacteria were identified as Pseudomonas sp. and Pseudomonas knackmussii, respectively. R10 released as much as 125.88 mg·L−1 dissolved P from tricalcium phosphate medium, while R4 released the most dissolved P from organic P medium among the isolates, with a concentration of 1.88 mg·L−1 and a releasing rate of 0.0078 mg·L−1·h−1 in ten days. P releasing increased with a pH decrease only when it was from inorganic P, not organic lecithin, and there was no significant correlation between the culture pH and P solubilizing. High-throughput sequencing analysis revealed that the dominant phylum in the studied wetland rhizosphere consisted of Acidobacteria, Proteobacteria, Bacteroidetes and Chloroflexi, accounting for 34.9%, 34.2%, 8.8% and 4.8%, respectively.

  9. PEROXIDE PROCESS FOR SEPARATION OF RADIOACTIVE MATERIALS

    Science.gov (United States)

    Seaborg, G.T.; Perlman, I.

    1958-09-16

    reduced state, from hexavalent uranium. It consists in treating an aqueous solution containing such uranium and plutonium ions with sulfate ions in order to form a soluble uranium sulfate complex and then treating the solution with a soluble thorium compound and a soluble peroxide compound in order to ferm a thorium peroxide carrier precipitate which carries down with it the plutonium peroxide present. During this treatment the pH of the solution must be maintained between 2 and 3.

  10. Antioxidant effect of bisphosphonates and simvastatin on chondrocyte lipid peroxidation

    International Nuclear Information System (INIS)

    Dombrecht, E.J.; De Tollenaere, C.B.; Aerts, K.; Cos, P.; Schuerwegh, A.J.; Bridts, C.H.; Van Offel, J.F.; Ebo, D.G.; Stevens, W.J.; De Clerck, L.S.

    2006-01-01

    The objective of this study was to evaluate the effect of bisphosphonates (BPs) and simvastatin on chondrocyte lipid peroxidation. For this purpose, a flow cytometrical method using C11-BODIPY 581/591 was developed to detect hydroperoxide-induced lipid peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP) induced a time and concentration dependent increase in chondrocyte lipid peroxidation. Addition of a Fe 2+ /EDTA complex to t-BHP or hydrogen peroxide (H 2 O 2 ) clearly enhanced lipid peroxidation. The lipophilic simvastatin demonstrated a small inhibition in the chondrocyte lipid peroxidation. None of three tested BPs (clodronate, pamidronate, and risedronate) had an effect on chondrocyte lipid peroxidation induced by t-BHP. However, when Fe 2+ /EDTA complex was added to t-BHP or H 2 O 2 , BPs inhibited the lipid peroxidation process varying from 25% to 58%. This study demonstrates that BPs have antioxidant properties as iron chelators, thereby inhibiting the chondrocyte lipid peroxidation. These findings add evidence to the therapeutic potential of bisphosphonates and statins in rheumatoid arthritis

  11. Microsomal lipid peroxidation as a mechanism of cellular damage. [Dissertation

    Energy Technology Data Exchange (ETDEWEB)

    Kornbrust, D.J.

    1979-01-01

    The NADPH/iron-dependent peroxidation of lipids in rat liver microsomes was found to be dependent on the presence of free ferrous ion and maintains iron in the reduced Fe/sup 2 +/ state. Chelation of iron by EDTA inhibited peroxidation. Addition of iron, after preincubation of microsomes in the absence of iron, did not enhance the rate of peroxidation suggesting that iron acts by initiating peroxidative decomposition of membrane lipids rather than by catalyzing the breakdown of pre-formed hydroperoxides. Liposomes also underwent peroxidation in the presence of ferrous iron at a rate comparable to intact microsomes and was stimulated by ascorbate. Carbon tetrachloride initiated lipid peroxidation in the absence of free metal ions. Rates of in vitro lipid peroxidation of microsomes and homogenates were found to vary widely between different tissues and species. The effects of paraquat on lipid peroxidation was also studied. (DC)

  12. Biotoxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system.

    Science.gov (United States)

    Pan, Tao; Liu, Chunyan; Zeng, Xinying; Xin, Qiao; Xu, Meiying; Deng, Yangwu; Dong, Wei

    2017-06-01

    A recent work has shown that hydrophobic organic compounds solubilized in the micelle phase of some nonionic surfactants present substrate toxicity to microorganisms with increasing bioavailability. However, in cloud point systems, biotoxicity is prevented, because the compounds are solubilized into a coacervate phase, thereby leaving a fraction of compounds with cells in a dilute phase. This study extends the understanding of the relationship between substrate toxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system. Biotoxicity experiments were conducted with naphthalene and phenanthrene in the presence of mixed nonionic surfactants Brij30 and TMN-3, which formed a micelle phase or cloud point system at different concentrations. Saccharomyces cerevisiae, unable to degrade these compounds, was used for the biotoxicity experiments. Glucose in the cloud point system was consumed faster than in the nonionic surfactant micelle phase, indicating that the solubilized compounds had increased toxicity to cells in the nonionic surfactant micelle phase. The results were verified by subsequent biodegradation experiments. The compounds were degraded faster by PAH-degrading bacterium in the cloud point system than in the micelle phase. All these results showed that biotoxicity of the hydrophobic organic compounds increases with bioavailability in the surfactant micelle phase but remains at a low level in the cloud point system. These results provide a guideline for the application of cloud point systems as novel media for microbial transformation or biodegradation.

  13. Inorganic precursor peroxides for antifouling coatings

    DEFF Research Database (Denmark)

    Olsen, S.M.; Pedersen, L.T.; Hermann, M.H.

    2009-01-01

    Modern antifouling coatings are generally based on cuprous oxide (Cu2O) and organic biocides as active ingredients. Cu2O is prone to bioaccumulation, and should therefore be replaced by more environmentally benign compounds when technically possible. However, cuprous oxide does not only provide...... antifouling properties, it is also a vital ingredient for the antifouling coating to obtain its polishing and leaching mechanism. In this paper, peroxides of strontium, calcium, magnesium, and zinc are tested as pigments in antifouling coatings. The peroxides react with seawater to create hydrogen peroxide...... matrix provides antifouling properties exceeding those of a similar coating based entirely on zinc oxide....

  14. EFFLUENT TREATMENT FACILITY PEROXIDE DESTRUCTION CATALYST TESTING

    International Nuclear Information System (INIS)

    HALGREN DL

    2008-01-01

    The 200 Area Effluent Treatment Facility (ETF) main treatment train includes the peroxide destruction module (PDM) where the hydrogen peroxide residual from the upstream ultraviolet light/hydrogen peroxide oxidation unit is destroyed. Removal of the residual peroxide is necessary to protect downstream membranes from the strong oxidizer. The main component of the PDM is two reaction vessels utilizing granular activated carbon (GAC) as the reaction media. The PDM experienced a number of operability problems, including frequent plugging, and has not been utilized since the ETF changed to groundwater as the predominant feed. The unit seemed to be underperforming in regards to peroxide removal during the early periods of operation as well. It is anticipated that a functional PDM will be required for wastewater from the vitrification plant and other future streams. An alternate media or methodology needs to be identified to replace the GAC in the PDMs. This series of bench scale tests is to develop information to support an engineering study on the options for replacement of the existing GAC method for peroxide destruction at the ETF. A number of different catalysts will be compared as well as other potential methods such as strong reducing agents. The testing should lead to general conclusions on the viability of different catalysts and identify candidates for further study and evaluation

  15. Ionizing radiation and lipid peroxidation in human body

    International Nuclear Information System (INIS)

    Giubileo, Gianfranco

    1997-07-01

    Lipids are organic compounds constituting the living cells. Lipid molecules can be disassembled through peroxidative pathways and hydrocarbons can be bred as end-product of lipid peroxidation in vivo. Lipid peroxidation can be started by an indirect effect of ionizing radiation. So a radioinduced cellular damage in human body can be detected by monitoring the production of specific hydrocarbons

  16. Carboxy terminated rubber based on natural rubber grafted with acid anhydrides and its adhesion properties

    International Nuclear Information System (INIS)

    Klinpituksa, P; Kongkalai, P; Kaesaman, A

    2014-01-01

    The chemical modification of natural rubber by grafting of various polar functional molecules is an essential method, improving the versatility of rubber in applications. This research investigated the preparation of natural rubber-graft-citraconic anhydride (NR-g-CCA), natural rubber-graft-itaconic anhydride (NR-g-ICA), and natural rubber-graft-maleic anhydride (NR-g-MA), with the anhydrides grafted to natural rubber in toluene using benzoyl peroxide as an initiator. Variations of monomer content, initiator content, temperature and reaction time of the grafting copolymerization were investigated. The maximum degrees of grafting were 1.06% for NR-g-CCA, 4.66% for NR-g-ICA, and 5.03% for NR-g-MA, reached using 10 phr citraconic anhydride, 10 phr of itaconic anhydride, or 8 phr of maleic anhydride, 3 phr benzoyl peroxide, at 85, 80 and 80°C for 2, 2 and 3 hrs, respectively. Solvent-based wood adhesives were formulated from these copolymers with various contents of wood resin in the range 10-40 phr. The maximal 289 N/in cleavage peel and 245.7 KPa shear strength for NR-g-MA (5.03% grafting) were obtained at 40 phr wood resin

  17. Deep Eutectic Solvent Aqueous Solutions as Efficient Media for the Solubilization of Hardwood Xylans.

    Science.gov (United States)

    Morais, Eduarda S; Mendonça, Patrícia V; Coelho, Jorge F J; Freire, Mara G; Freire, Carmen S R; Coutinho, João A P; Silvestre, Armando J D

    2018-02-22

    This work contributes to the development of integrated lignocellulosic-based biorefineries by the pioneering exploitation of hardwood xylans by solubilization and extraction in deep eutectic solvents (DES). DES formed by choline chloride and urea or acetic acid were initially evaluated as solvents for commercial xylan as a model compound. The effects of temperature, molar ratio, and concentration of the DES aqueous solutions were evaluated and optimized by using a response surface methodology. The results obtained demonstrated the potential of these solvents, with 328.23 g L -1 of xylan solubilization using 66.7 wt % DES in water at 80 °C. Furthermore, xylans could be recovered by precipitation from the DES aqueous media in yields above 90 %. The detailed characterization of the xylans recovered after solubilization in aqueous DES demonstrated that 4-O-methyl groups were eliminated from the 4-O-methylglucuronic acids moieties and uronic acids (15 %) were cleaved from the xylan backbone during this process. The similar M w values of both pristine and recovered xylans confirmed the success of the reported procedure. DES recovery in four additional extraction cycles was also demonstrated. Finally, the successful extraction of xylans from Eucalyptus globulus wood by using aqueous solutions of DES was demonstrated. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Characterization and bioremediation potential of phosphate solubilizing bacteria isolated from tunisian phosphogypsum

    International Nuclear Information System (INIS)

    Trifi, Houda

    2011-01-01

    Phosphorus bioavailability is often limited in agricultural soils. In this work, two bacteria were isolated from Tunisian phosphogypsum (PG). These ones have the capacity to dissolve inorganic phosphate (CaHPO 4 and Ca 3 (PO 4 ) 2 ). This capacity is determined by the clear halo formation around colonies in NBRIP agar medium. To confirm the solubilization phenotype, the concentration of solubilized phosphate by isolates cultivated in NBRIP broth containing PG was measured. These two bacteria noted BRM17 and BRM18 are identified as Pantoea sp. and Pseudomonas sp, respectively. The results show that BRM17 solubilizes about 2 times more phosphate in broth NBRIP medium after 48 hours of incubation than BRM18. Tunisian phosphogypsum contains 1100 ppm of strontium (Sr). Sr toxicity on bacteria was determined by concentration that gives half-maximal inhibition of bacteria (IC 50 ). Compared with Cupriavidus metallidurans (bacteria tolerant to most of heavy metals), BRM17 and BRM18 cultivated in broth medium containing increasing concentrations of Sr were found tolerant to Sr. The potential of bioremediation is tested by the rate evaluation of Sr adsorption by these bacteria. The results show the high ability of BRM18 to adsorb Sr. The resistance of isolates to ionizing radiation is also determined by the exposure of bacterial cultures to various doses of gamma radiation. BRM17 is considered radioresistant while BRM18 is radiosensitive. The effect on seed germination of wheat and pea inoculated with bacteria was tested. No positive effect was detected. This study is considered with the use of BRM17 and BRM18 in a bioremediation process and the improvement of phosphate uptake by plants cultivated in polluted environments.

  19. Solubilization of industrial grade plant protein by enzymatic hydrolysis monitored by vibrational and nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Bevilacqua, Marta; Pratico, Giulia; Plesner, Johanne

    2017-01-01

    Protein hydrolysates are of great interest in the food industry due to their nutritional and functional properties, but their use often implies solubilization in water and therefore hamper the use of plant proteins with inherent low water solubility. Protein solubility in water can be modified...... (1H NMR and IR) coupled with chemometrics analysis in monitoring the hydrolysis of five different industrial grade plant proteins by the enzyme Alcalase. Logarithmic modeling of the PCA (Principal Component Analysis) scores confirmed that they can represent a measurement of the solubilized protein...

  20. Pesticide tolerant and phosphorus solubilizing Pseudomonas sp. strain SGRAJ09 isolated from pesticides treated Achillea clavennae rhizosphere soil.

    Science.gov (United States)

    Rajasankar, R; Manju Gayathry, G; Sathiavelu, A; Ramalingam, C; Saravanan, V S

    2013-05-01

    In this study, an attempt was made to identify an effective phosphate solubilizing bacteria from pesticide polluted field soil. Based on the formation of solubilization halo on Pikovskaya's agar, six isolates were selected and screened for pesticide tolerance and phosphate (P) solubilization ability through liquid assay. The results showed that only one strain (SGRAJ09) obtained from Achillea clavennae was found to tolerate maximum level of the pesticides tested and it was phylogenetically identified as Pseudomonas sp. It possessed a wide range of pesticide tolerance, ranging from 117 μg mL(-1) for alphamethrin to 2,600 μg mL(-1) for endosulfan. The available P concentrations increased with the maximum and double the maximum dose of monocrotophos and imidacloprid, respectively. On subjected to FT-IR and HPLC analysis, the presence of organic acids functional group in the culture broth and the production of gluconic acid as dominant acid aiding the P solubilization were identified. On comparison with control broth, monocrotophos and imidacloprid added culture broth showed quantitatively high organic acids production. In addition to gluconic acid production, citric and acetic acids were also observed in the pesticide amended broth. Furthermore, the Pseudomonas sp. strain SGRAJ09 possessed all the plant growth promoting traits tested. In presence of monocrotophos and imidacloprid, its plant growth promoting activities were lower than that of the pesticides unamended treatment.

  1. STUDI CAMPURAN SURFACTANT UNTUK MENENTUKAN FUNGSI SOLUBILIZER DAN FIXATIVE PADA INDUSTRI PARFUM

    Directory of Open Access Journals (Sweden)

    K N Adli

    2016-03-01

    Full Text Available Kualitas parfum  ditentukan oleh kejernihan dan longlasting parfum. Campuran surfaktan dapat meningkatkan kualitas parfum dengan biaya produksi yang murah. Penelitian ini bertujuan untuk mengkaji rasio campuran surfaktan untuk menentukan fungsi solubilizer dan fixative. Bibit parfum yang digunakan dalam penelitian ini adalah eugenol, surfaktan dengan fungsi solubilizer adalah portasol 40 dan tween 80 sedangkan surfaktan dengan fungsi fixative adalah glucam P20 dan patchouli alkohol. Rasio yang digunakan pada penelitian ini antara lain rasio glucam p20 : portasol (r G/P, rasio portasol 40 : tween 80 (r P/T dan rasio glucam P20 : patchouli alkohol (r G/PA. Hasil penelitian menunjukkan campuran surfaktan dapat meningkatkan kejernihan dan longlasting parfum lebih baik daripada surfaktan tunggal. Optimasi menggunakan RSM didapatkan rasio campuran yang paling berpengaruh terhadap kejernihan adalah r P/T sedangkan rasio yang paling berpengaruh terhadap longlasting parfum adalah r G/PA. Hasil optimum dengan respon turbiditas r G/P = 3,59; r P/T = 0,48; r G/PA = 0,41 dan respon longlasting  r G/P = 4,51; r P/T = 0,40; r G/PA = 0,42 menghasilkan turbiditas 0,0489 NTU serta longlasting 3,68 jam.Perfume quality is determined by the clarity and longlasting perfume. Surfactant mixture can improve the quality of perfumes at low production costs. This study objectives are to examines the blending ratio surfactant and to determine the function of solubilizer and fixative. Perfume seeds used in this study is eugenol, surfactants with solubilizer function is Portasol 40 and Tween 80 while surfactant with fixative function are glucam P20 and patchouli alcohol. The ratio used in this study include glucam ratio P20: portasol (r G/P, the ratio portasol 40: tween 80 (rP/T and the ratio of glucam P20: patchouli alcohol (r G/PA. The results showed a mixture of surfactants may improve the clarity and longlasting perfume is better than a single surfactant. RSM

  2. PROCESS OF ELIMINATING HYDROGEN PEROXIDE IN SOLUTIONS CONTAINING PLUTONIUM VALUES

    Science.gov (United States)

    Barrick, J.G.; Fries, B.A.

    1960-09-27

    A procedure is given for peroxide precipitation processes for separating and recovering plutonium values contained in an aqueous solution. When plutonium peroxide is precipitated from an aqueous solution, the supernatant contains appreciable quantities of plutonium and peroxide. It is desirable to process this solution further to recover plutonium contained therein, but the presence of the peroxide introduces difficulties; residual hydrogen peroxide contained in the supernatant solution is eliminated by adding a nitrite or a sulfite to this solution.

  3. Genome Sequence of Selenium-Solubilizing Bacterium Caulobacter vibrioides T5M6

    DEFF Research Database (Denmark)

    Wang, Yihua; Qin, Yanan; Kot, Witold

    2016-01-01

    Caulobacter vibrioides T5M6 is a Gram-negative strain that strongly solubilizes selenium (Se) mineral into Se(IV) and was isolated from a selenium mining area in Enshi, southwest China. This strain produces the phytohormone IAA and promotes plant growth. Here we present the genome of this strain...

  4. Sucrose dependent mineral phosphate solubilization in Enterobacter asburiae PSI3 by heterologous overexpression of periplasmic invertases.

    Science.gov (United States)

    Kumar, Chanchal; Wagh, Jitendra; Archana, G; Naresh Kumar, G

    2016-12-01

    Enterobacter asburiae PSI3 solubilizes mineral phosphates in the presence of glucose by the secretion of gluconic acid generated by the action of a periplasmic pyrroloquinoline quinone dependent glucose dehydrogenase. In order to achieve mineral phosphate solubilization phenotype in the presence of sucrose, plasmids pCNK4 and pCNK5 containing genes encoding the invertase enzyme of Zymomonas mobilis (invB) and of Saccharomyces cerevisiae (suc2) under constitutive promoters were constructed with malE signal sequence (in case of invB alone as the suc2 is secreted natively). When introduced into E. asburiae PSI3, E. a. (pCNK4) and E. a. (pCNK5) transformants secreted 21.65 ± 0.94 and 22 ± 1.3 mM gluconic acid, respectively, in the presence of 75 mM sucrose and they also solubilized 180 ± 4.3 and 438 ± 7.3 µM P from the rock phosphate. In the presence of a mixture of 50 mM sucrose and 25 mM glucose, E. a. (pCNK5) secreted 34 ± 2.3 mM gluconic acid and released 479 ± 8.1 µM P. Moreover, in the presence of a mixture of eight sugars (10 mM each) in the medium, E. a. (pCNK5) released 414 ± 5.3 µM P in the buffered medium. Thus, this study demonstrates incorporation of periplasmic invertase imparted P solubilization ability to E. asburiae PSI3 in the presence of sucrose and mixture of sugars.

  5. Synthesis, screening and QSAR studies of 3-benzoyl-2-oxo/thioxo-1,2,3,4-tetrahydro-pyrimidine analogues as antibacterial agents

    Directory of Open Access Journals (Sweden)

    Ramesh L. Sawant

    2008-12-01

    Full Text Available The purpose of this study was to synthesize several 3-benzoyl-5-acyl-6-methyl-4-substituted-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidines, evaluate them for their antibacterial activity and to establish correlation between the activity and physicochemical properties. 5-Acyl-6-methyl-4-substituted-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidines (A were synthesized by cyclocondensation reaction between appropriate aldehyde, acetoacetate and urea/thiourea in presence of aluminium chloride and hydrochloric acid which upon treatment with benzoyl chloride in presence of pyridine in benzene furnish the title compounds (1-28. The structures of all title compounds have been confirmed on the basis of their analytical, IR and NMR spectral data. The title compounds have been tested for antibacterial activity against Staphylococcus aureus. The compounds were divided into training and test sets. A quantitative structure activity relationship study was made using various descriptors. Several statistical expressions were developed using stepwise multiple linear regression analysis. The best quantitative structure activity relationship model was further cross validated. The study revealed that total positive partial charge (PC+ and total polar negative Van der Waals surface area (Q_VSA_PNEG contributes negatively where as contribution of Van der Waals surface area to molar refractivity (SMR_VSA7 contributes positively to the antibacterial activity. The compounds with improved antibacterial potential can be successfully designed with selected quantitative structure activity relationship model.

  6. Radiation effect on lipid peroxide content of spices

    International Nuclear Information System (INIS)

    Kaneko, Nobutada; Ito, Hitoshi; Ishigaki, Isao

    1990-01-01

    To evaluate the radiation-induced deterioration of lipid in spices, peroxide value, iodine value and acid value were measured after extraction by chloroform. Peroxide values of black pepper and white pepper were not increased by gamma-irradiation with doses below 30 kGy and gradually increased at higher dose up to 80 kGy in this study. On contrary, peroxide values of clove and rosemary increased rather quickly below 20 kGy of gamma-irradiation, and they became stationary at higher dose. Iodine values and acid values had relationship with peroxide values on each kind of spices. On the storage study of irradiated spices, peroxide values decreased quickly during 20 days storage as same as nonirradiated spices, and it became stationary after 20 to 50 days storage at 30degC. Enhancement of oxidized deterioration were not observed even higher irradiation doses up to 80 kGy in this study. (author)

  7. Effects of Phosphorus Solubilizing Bacteria and Nitrogen on the Qualitative and Quantitative Properties of Tuberose (Polianthes tuberosa

    Directory of Open Access Journals (Sweden)

    T. Taher

    2016-02-01

    Full Text Available Introduction: In Iran, tuberose is ranked the forth after gladiolus, rose and carnation. These flowers are known as high quality products among which maximum exportation belongs to tuberose and gladiolus. In plant cultivation and development, adequate provision of nutrients is of crucial importance. Tuberose needs plenty of nutrients to obtain the desirable quality and flowering. Hence, tuberose balanced nutrition can play an important role in increasing the yield and quality of its flowers. Nitrogen is a deciding factor for the plant growth and physiology. This nutritional element contributes to the formation of amino acids, proteins, nucleic acids and other cellular components that are required for the construction of new cells. Bio fertilizers containing phosphate solubilizing bacteria (bacillus and pseudomonas have microorganisms which are beneficial to the soil; these bacteria are conducive to the production of biological materials and as a consequence to plant development. According to a report by Rawia Eid et al., (2009 the application of phosphate solubilizing bacteria increased the growth rate of matthiola cut flower and improved its quality. In another study on soybean, it was observed that the application of phosphate solubilizing bacteria led to a rise in the plant dry matter content. Considering the contributory role of nitrogen and phosphorous in increasing the yield and quality of ornamental plants, the aim of this research was to examine the impact of different nitrogen levels and phosphate solubilizing bacteria on the yield and qualitative properties of tuberose cut flower. Materials and Methods: This research was carried out in a greenhouse in the city of Zanjan in Iran in 2011 through a factorial-form experiment based on a randomized complete block design with three replications and twelve treatments performed on tuberose double cultivar. The treatments included bio fertilizer containing phosphate solubilizing bacteria at

  8. Acid- and base-catalysis in the mononuclear rearrangement of some (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole in toluene: effect of substituents on the course of reaction.

    Science.gov (United States)

    D'Anna, Francesca; Frenna, Vincenzo; Ghelfi, Franco; Marullo, Salvatore; Spinelli, Domenico

    2011-04-15

    The reaction rates for the rearrangement of eleven (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole 3a-k into the relevant (2-aryl-5-phenyl-2H-1,2,3-triazol-4-yl)ureas 4a-k in the presence of trichloroacetic acid or of piperidine have been determined in toluene at 313.1 K. The results have been related to the effect of the aryl substituent by using Hammett and/or Ingold-Yukawa-Tsuno correlations and have been compared with those previously collected in a protic polar solvent (dioxane/water) as well as with those on the analogous rearrangement of the corresponding (Z)-arylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole 1a-k in benzene. Some light can thus be shed on the general differences of chemical reactivity between protic polar (or dipolar aprotic) and apolar solvents.

  9. Role of the CipA Scaffoldin Protein in Cellulose Solubilization, as Determined by Targeted Gene Deletion and Complementation in Clostridium thermocellum

    Science.gov (United States)

    Olson, Daniel G.; Giannone, Richard J.; Hettich, Robert L.

    2013-01-01

    The CipA scaffoldin protein plays a key role in the Clostridium thermocellum cellulosome. Previous studies have revealed that mutants deficient in binding or solubilizing cellulose also exhibit reduced expression of CipA. To confirm that CipA is, in fact, necessary for rapid solubilization of crystalline cellulose, the gene was deleted from the chromosome using targeted gene deletion technologies. The CipA deletion mutant exhibited a 100-fold reduction in cellulose solubilization rate, although it was eventually able to solubilize 80% of the 5 g/liter cellulose initially present. The deletion mutant was complemented by a copy of cipA expressed from a replicating plasmid. In this strain, Avicelase activity was restored, although the rate was 2-fold lower than that in the wild type and the duration of the lag phase was increased. The cipA coding sequence is located at the beginning of a gene cluster containing several other genes thought to be responsible for the structural organization of the cellulosome, including olpB, orf2p, and olpA. Tandem mass spectrometry revealed a 10-fold reduction in the expression of olpB, which may explain the lower growth rate. This deletion experiment adds further evidence that CipA plays a key role in cellulose solubilization by C. thermocellum, and it raises interesting questions about the differential roles of the anchor scaffoldin proteins OlpB, Orf2p, and SdbA. PMID:23204466

  10. Hydrogen peroxide probes directed to different cellular compartments.

    OpenAIRE

    Mikalai Malinouski; You Zhou; Vsevolod V Belousov; Dolph L Hatfield; Vadim N Gladyshev

    2011-01-01

    Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular ...

  11. Sugar microanalysis by HPLC with benzoylation: improvement via introduction of a C-8 cartridge and a high efficiency ODS column.

    Science.gov (United States)

    Miyagi, Michiko; Yokoyama, Hirokazu; Hibi, Toshifumi

    2007-07-01

    An HPLC protocol for sugar microanalysis based on the formation of ultraviolet-absorbing benzoyl chloride derivatives was improved. Here, samples were prepared with a C-8 cartridge and analyzed with a high efficiency ODS column, in which porous spherical silica particles 3 microm in diameter were packed. These devices allowed us to simultaneously quantify multiple sugars and sugar alcohols up to 10 ng/ml and to provide satisfactory separations of some sugars, such as fructose and myo-inositol and sorbitol and mannitol. This protocol, which does not require special apparatuses, should become a powerful tool in sugar research.

  12. Reconstitution of hormone-responsive detergent-solubilized follicle stimulating hormone receptors into liposomes

    International Nuclear Information System (INIS)

    Grasso, P.; Dattatreyamurty, B.; Reichert, L.E. Jr.

    1988-01-01

    An FSH receptor-enriched fraction that responds to exogenous FSH by activation of adenylate cyclase was prepared by ultrafiltration of sucrose density gradient-purified light membranes derived from bovine calf testes homogenates and solubilized with Triton X-100. To further confirm the functional nature of the detergent-solubilized FSH receptor, the extract was incorporated by lipid hydration into large multilamellar vesicles composed of dioleoyl phosphatidylcholine and cholesterol, 2:1 molar ratio. Receptor incorporation was determined by measurement of specific binding of [125I] human FSH ([125I] hFSH). Substitution of dioleoyl phosphatidylcholine with dipalmitoyl phosphatidylcholine or increasing the cholesterol concentration of the vesicles reduced specific binding of [125I]hFSH. Under conditions favoring optimal incorporation of the receptor, specific binding of [125I]hFSH was time and temperature dependent and saturable when increasing concentrations of radioligand were added to a constant amount of proteoliposomes. Reconstituted proteoliposomes bound 1600 fmol FSH/mg protein with an affinity of 3.54 x 10(9) M-1. Inhibition of [125I] hFSH binding by hFSH was comparable to that seen with the membrane-bound receptor (ED50 = 10 ng). Equilibrium binding studies with [3H]Gpp(NH)p indicated that a single class of high affinity GTP binding sites with an association constant (Ka) of 3.33 x 10(7) m-1 which bound 2.19 fmol [3H]Gpp(NH)p/mg protein had also been incorporated into the proteoliposomes. Addition of FSH induced a 2-fold stimulation of [3H]Gpp(NH)p binding, supporting our earlier studies suggesting that the detergent-solubilized FSH receptor is complexed to the G protein. Of particular significance in the present study was the observation that both NaF and FSH stimulated cAMP production in the reconstituted system

  13. Low-Resolution Structure of Detergent-Solubilized Membrane Proteins from Small-Angle Scattering Data.

    Science.gov (United States)

    Koutsioubas, Alexandros

    2017-12-05

    Despite the ever-increasing usage of small-angle scattering as a valuable complementary method in the field of structural biology, applications concerning membrane proteins remain elusive mainly due to experimental challenges and the relative lack of theoretical tools for the treatment of scattering data. This fact adds up to general difficulties encountered also by other established methods (crystallography, NMR) for the study of membrane proteins. Following the general paradigm of ab initio methods for low-resolution restoration of soluble protein structure from small-angle scattering data, we construct a general multiphase model with a set of physical constraints, which, together with an appropriate minimization procedure, gives direct structural information concerning the different components (protein, detergent molecules) of detergent-solubilized membrane protein complexes. Assessment of the method's precision and robustness is evaluated by performing shape restorations from simulated data of a tetrameric α-helical membrane channel (Aquaporin-0) solubilized by n-Dodecyl β-D-Maltoside and from previously published small-angle neutron scattering experimental data of the filamentous hemagglutinin adhesin β-barrel protein transporter solubilized by n-Octyl β-D-glucopyranoside. It is shown that the acquisition of small-angle neutron scattering data at two different solvent contrasts, together with an estimation of detergent aggregation number around the protein, permits the reliable reconstruction of the shape of membrane proteins without the need for any prior structural information. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  14. Solubilization of docetaxel in poly(ethylene oxide)-block-poly(butylene/styrene oxide) micelles.

    Science.gov (United States)

    Elsabahy, Mahmoud; Perron, Marie-Eve; Bertrand, Nicolas; Yu, Ga-Er; Leroux, Jean-Christophe

    2007-07-01

    Poly(ethylene oxide)-block-poly(styrene oxide) (PEO-b-PSO) and PEO-b-poly(butylene oxide) (PEO-b-PBO) of different chain lengths were synthesized and characterized for their self-assembling properties in water by dynamic/static light scattering, spectrofluorimetry, and transmission electron microscopy. The resulting polymeric micelles were evaluated for their ability to solubilize and protect the anticancer drug docetaxel (DCTX) from degradation. The drug release kinetics as well as the cytotoxicity of the loaded micelles were assessed in vitro. All polymers formed micelles with a highly viscous core at low critical association concentrations (hydrolysis under accelerated stability testing conditions. Only PEO-b-PBO bearing 24 BO units afforded significant protection against degradation. In vitro, DCTX was released slower from the latter micelles, but all formulations possessed a similar cytotoxic effect against PC-3 prostate cancer cells. These data suggest that PEO-b-P(SO/BO) micelles could be used as alternatives to conventional surfactants for the solubilization of taxanes.

  15. Water solubilization and the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid

    Energy Technology Data Exchange (ETDEWEB)

    Demchenko, P.A.; Novitskaya, L.D.

    The investigation of the dependence of water solubilization on the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid in benzene has shown that at certain acid additions, the solubilization effect can increase almost 6 times, as compared to the soap solution without acid additions. In some cases, electron donor-acceptor complexes are formed, which are more polar than the original components. This leads to a change in the molecular-disperse and micellar part of solution and affects significantly the structure and properties of micellar hydrocarbon solutions of surfactants.

  16. Synergistic extraction of trivalent lanthanoids with 3-phenyl-4-benzoyl-5-isoxazolone and various sulphoxides

    International Nuclear Information System (INIS)

    Sahu, S.K.; Chakravortty, V.; Reddy, M.L.P.; Ramamohan, T.R.

    1999-01-01

    Synergistic extraction of trivalent lanthanoids Nd, Tb and Tm with mixtures of 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) and dioctyl sulphoxide (DOSO), bis-2-ethylhexyl sulphoxide (B2EHSO) or diphenyl sulphoxide (DPhSO) in xylene from perchlorate solution was investigated. Lanthanoids were found to be extracted as Ln(PBI) 3 with HPBI alone. In the presence of sulphoxides, Nd(III) was found to be extracted as Nd(PBI) 3 . S and Nd(PBI) 3 . 2 S (where S = sulphoxide). On the other hand, Tb(III) and Tm(III) were extracted as Tb(PBI) 3 . S and Tm(PBI) 3 . S respectively. The equilibrium constants of the synergistic species were found to increase monotonically with decreasing ionic radii of these metal ions. The addition of a sulphoxide to the metal chelate system not only enhances the extraction efficiency but also improves the selectivities among these trivalent lanthanoids. (orig.)

  17. Solubilization of silk protein by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sudatis, Boonya; Pongpat, Suchada [Office of Atomic Energy of Peace, Bangkok (Thailand)

    2002-03-01

    Gamma irradiated silk fibroin at doses of 0, 5, 10, 20, 40, 60, 80, 100, 125, 250, 500, 750 and 1000 kGy were soaked in water for 1 hr. Silk fibroin solubilized percentage was investigated from lost weight of sample (dried at 105{sup 0}C), they were 0, 0, 0.7, 0, 0.11, 0.11, 0, 0.73, 0.77, 4.38, 8.32, 10.22 and 18.52 respectively. It showed that at the higher dose up to 250 kGy had direct effect to solubility, and increased with increasing dose. In addition, silk sericin dissolved 77.76, 82.22, 83.55, 84.31, 86.04, 86.67 and 87.37% after gamma irradiation at the doses of 0, 50, 100, 200, 500, 750 and 1000 kGy respectively. It presents that radiation can cause silk protein, fibroin and sericin dissolve because of their degradation. (author)

  18. Isolation, Characterization, and Molecular Identification of Phosphate Solubilizing Bacteria from Several Tropical Soils

    Directory of Open Access Journals (Sweden)

    Fahrizal Hazra

    2013-03-01

    Full Text Available The objectives of the research were: (i to isolate and characterize of phosphate solubilizing bacteria (PSB and (ii to identify PSB based on molecular amplification of 16S rRNA gene. Soil samples were collected from rhizosphere in Bogor, West Nusa Tenggara, and East Nusa Tenggara. Several stages in this research were: (i isolation PSB in Pikovskaya agar, (ii morphological and biochemical characterization of PSB, (iii measurement of phosphatase enzymes, and (iv measurement of secreting indole acetic acid phytohormone. As many as 29 isolates of PSB have been collected and three isolates of them, namely: P 3.5 (East Nusa Tenggara, P 6.2 (West Nusa Tenggara, and P 10.1 (Citeureup, West Java were chosen for further study. There were many characteristics of isolate P 10.1: (i it had capable to solubilize P with the value of highest solubilization index (1.80, (ii it had the highest phosphatase enzyme (120.40 mg kg-1, and (iii it had the highest pH decrease at each observation for six days. Isolates P 3.5 and P 10.1 were the Gram-negative bacteria with coccus shapes and isolate P 6.2 was a Gram-negative bacteria with bacillus shape. Deoxiribonucleat Acid (DNA amplification of these bacteria employing 16S rRNA primers generated the 1,300bp-PCR product. The results of the analysis of 16S rRNA gene sequences showed that isolates P 3.5 and P 10.1 has 98% similarity with Gluconacetobacter sp. strains Rg1-MS-CO and isolate P 6.2 has 97% similarity with Enterobacter sp. pp9c strains.

  19. Solubilization of insoluble zinc compounds by Gluconacetobacter diazotrophicus and the detrimental action of zinc ion (Zn2+) and zinc chelates on root knot nematode Meloidogyne incognita.

    Science.gov (United States)

    Saravanan, V S; Kalaiarasan, P; Madhaiyan, M; Thangaraju, M

    2007-03-01

    To examine the zinc (Zn) solubilization potential and nematicidal properties of Gluconacetobacter diazotrophicus. Atomic Absorption Spectrophotometer, Differential Pulse Polarography and Gas Chromatography Coupled Mass Spectrometry were used to estimate the total Zn and Zn(2+) ions and identify the organic acids present in the culture supernatants. The effect of culture filtrate of Zn-amended G. diazotrophicus PAl5 on Meloidogyne incognita in tomato was examined under gnotobiotic conditions. Gluconacetobacter diazotrophicus PAl5 effectively solubilized the Zn compounds tested and 5-ketogluconic acid was identified as the major organic acid aiding the solubilization of zinc oxide. The presence of Zn compounds in the culture filtrates of G. diazotrophicus enhanced the mortality and reduced the root penetration of M. incognita under in vitro conditions. 5-ketogluconic acid produced by G. diazotrophicus mediated the solubilization process and the available Zn(2+) ions enhanced the nematicidal activity of G. diazotrophicus against M. incognita. Zn solubilization and enhanced nematicidal activity of Zn-amended G. diazotrophicus provides the possibility of exploiting it as a plant growth promoting bacteria.

  20. Winter rye as a bioenergy feedstock: impact of crop maturity on composition, biological solubilization and potential revenue.

    Science.gov (United States)

    Shao, Xiongjun; DiMarco, Kay; Richard, Tom L; Lynd, Lee R

    2015-01-01

    Winter annual crops such as winter rye (Secale cereale L) can produce biomass feedstock on seasonally fallow land that continues to provide high-value food and feed from summer annuals such as corn and soybeans. As energy double crops, winter grasses are likely to be harvested while still immature and thus structurally different from the fully senesced plant material typically used for biofuels. This study investigates the dynamic trends in biomass yield, composition, and biological solubilization over the course of a spring harvest season. The water soluble fraction decreased with increasing maturity while total carbohydrate content stayed roughly constant at about 65%. The protein mass fraction decreased with increasing maturity, but was counterbalanced by increasing harvest yield resulting in similar total protein across harvest dates. Winter rye was ground and autoclaved then fermented at 15 g/L total solids by either (1) Clostridium thermocellum or (2) simultaneous saccharification and cofermentation (SSCF) using commercial cellulases (CTec2 and HTec2) and a xylose-fermenting Saccharomyces cerevisiae strain. Solubilization of total carbohydrate dropped significantly as winter rye matured for both C. thermocellum (from approximately 80% to approximately 50%) and SSCF (from approximately 60% to approximately 30%). C. thermocellum achieved total solubilization 33% higher than that of SSCF for the earliest harvest date and 50% higher for the latest harvest date. Potential revenue from protein and bioethanol was stable over a range of different harvest dates, with most of the revenue due to ethanol. In a crop rotation with soybean, recovery of the soluble protein from winter rye could increase per hectare protein production by 20 to 35%. Double-cropping winter rye can produce significant biomass for biofuel production and feed protein as coproduct without competing with the main summer crop. During a 24-day harvest window, the total carbohydrate content remained

  1. A chemiluminescent method for determination of lipid peroxidation

    International Nuclear Information System (INIS)

    Liang Xiaofeng; Hu Tianxi; Fan Xiaobing

    2003-01-01

    We established a chemiluminescent system for determination of lipid peroxidation and screening anti-oxidants. The lipid containing unsaturated fatly acids was injected into a galls tube. Luminol solution and the deionized water were added into it too. The glass tube was put into a preincubation box to incubate it for 0.5 h at 37 degree C. AAPH solution was injected into the tube for immediate measurement in a biochemiluminometer at 38-39 degree C. The pulses /6s(CP6s) were determined with T-2 program. Chemiluminescent dynamic and lipid peroxidation changes were observed continuously. Once the CL intensity of lipid peroxidation got peak, the antioxidant which has different concentration was added immediately in situ. A certain CL intensity (CP6s) was chosen as evaluation index to compare the activity of antioxidants. A luminol chemiluminescent system for determination of lipid peroxidation has been made. It was found that Vit. C, teapolyphenol, and glutathione have effects on scavenging lipid free radicals. The new method is quick, sensitive, and simple for determination of lipid peroxidation and screening antioxidants

  2. Acyclic cucurbit[n]uril-type molecular containers: influence of glycoluril oligomer length on their function as solubilizing agents.

    Science.gov (United States)

    Gilberg, Laura; Zhang, Ben; Zavalij, Peter Y; Sindelar, Vladimir; Isaacs, Lyle

    2015-04-07

    We present the synthesis of a series of six new glycoluril derived molecular clips and acyclic CB[n]-type molecular containers (1–3) that all feature SO3(−) solubilizing groups but differ in the number of glycoluril rings between the two terminal dialkoxyaromatic sidewalls. We report the X-ray crystal structure of 3b which shows that its dialkoxynaphthalene sidewalls actively define a hydrophobic cavity with high potential to engage in π–π interactions with insoluble aromatic guests. Compounds 1–3 possess very good solubility characteristics (≥38 mM) and undergo only very weak self-association (Ks containers 3a and 3b which feature three glycoluril rings between the terminal dialkoxy-o-xylylene and dialkoxynaphthalene sidewalls are less efficient solubilizing agents than 4a and 4b because of their smaller hydrophobic cavities. Containers 1 and 2 behave as molecular clip type receptors and therefore possess the ability to bind to and thereby solubilize aromatic drugs like camptothecin, ziprasidone, and PBS-1086.

  3. Micellar solubilization in strongly interacting binary surfactant systems. [Binary surfactant systems of: dodecyltrimethylammonium chloride + sodium dodecyl sulfate; benzyldimethyltetradecylammonium chloride + tetradecyltrimethylammonium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Treiner, C. (Universite Pierre et Marie Curie, Paris (France)); Nortz, M.; Vaution, C. (Faculte de Pharmacie de Paris-sud, Chatenay-Malabry (France))

    1990-07-01

    The apparent partition coefficient P of barbituric acids between micelles and water has been determined in mixed binary surfactant solutions from solubility measurements in the whole micellar composition range. The binary systems chosen ranged from the strongly interacting system dodecyltrimethylammonium chloride + sodium dodecyl sulfate to weakly interacting systems such as benzyldimethyltetradecylammonium chloride + tetradecyltrimethyammonium chloride. In all cases studied, mixed micelle formation is unfavorable to micellar solubilization. A correlation is found between the unlike surfactants interaction energy, as measured by the regular solution parameter {beta} and the solute partition coefficient change upon surfactant mixing. By use of literature data on micellar solubilization in binary surfactant solutions, it is shown that the change of P for solutes which are solubilized by surface adsorption is generally governed by the sign and amplitude of the interaction parameter {beta}.

  4. Synthesis and thermal properties of strontium and calcium peroxides

    Science.gov (United States)

    Philipp, Warren H.; Kraft, Patricia A.

    1989-01-01

    A practical synthesis and a discussion of some chemical properties of pure strontium peroxide and calcium peroxide are presented. The general synthesis of these peroxides involves precipitation of their octahydrates by addition of H2O2 to aqueous ammoniacal Sr(NO3)2 or CaCl2. The octahydrates are converted to the anhydrous peroxides by various dehydration techniques. A new x-ray diffraction powder pattern for CaO2 x 8H2O is given from which lattice parameters a=6.212830 and c=11.0090 were calculated on the basis of the tetragonal crystal system.

  5. The problem of peroxidation in radiolis logy

    International Nuclear Information System (INIS)

    Baraboj, V.A.; Chebotarev, E.E.

    1986-01-01

    A hypothesis is validated concerning the products of freeradical oxidation of lipids and the phenol compounds as a mediator of the stress-syndrome. The data are reviewed on activation of peroxidation under the effect of radiation, cytochemical agents, etc., secondarily stimulating the neurohumoral system function of homeostasis regulation. With the emotional-algesic and cold-stresses, the regulatory system stimulation is of primary, reflex, nature, but it secondarily promotes the peroxidation activation. The radiotoxins (of the quinoid and lipid nature) appearing in tissues under the effect of ionizing radiation, are smilar in structure and mechanism of action to peroxidation activation products formed under the effect of other stress-agents

  6. Thermodynamic study on competitive solubilization of cholesterol and beta-sitosterol in bile salt micelles.

    Science.gov (United States)

    Matsuoka, Keisuke; Hirosawa, Takashi; Honda, Chikako; Endo, Kazutoyo; Moroi, Yoshikiyo; Shibata, Osamu

    2007-07-01

    Differences in the preferential solubilization of cholesterol and competitive solubilizates (beta-sitosterol and aromatic compounds) in bile salt micelles was systematically studied by changing the molar ratio of cholesterol to competitive solubilizates. The cholesterol solubility in a mixed binary system (cholesterol and beta-sitosterol) was almost half that of the cholesterol alone system, regardless of the excess beta-sitosterol quantity added. On the other hand, the mutual solubilities of cholesterol and pyrene were not inhibited by their presence in binary mixed crystals. Finally, the cholesterol solubility was measured by changing the alkyl chain length of n-alkylbenzenes. When tetradecylbenzene was added to the bile solution, the cholesterol solubility decreased slightly and was below the original cholesterol solubility. Based on Gibbs energy change (DeltaG degrees ) for solubilization, chemicals that inhibit cholesterol solubility in their combined crystal systems showed a larger negative DeltaG degrees value than cholesterol alone.

  7. Combined application of bio-organic phosphate and phosphorus solubilizing bacteria (Bacillus strain MWT 14) improve the performance of bread wheat with low fertilizer input under an arid climate.

    Science.gov (United States)

    Tahir, Muhammad; Khalid, Umaira; Ijaz, Muhammad; Shah, Ghulam Mustafa; Naeem, Muhammad Asif; Shahid, Muhammad; Mahmood, Khalid; Ahmad, Naveed; Kareem, Fazal

    2018-04-24

    This study was aimed to investigate the effect of bio-organic phosphate either alone or in combination with phosphorus solubilizing bacteria strain (Bacillus MWT-14) on the growth and productivity of two wheat cultivars (Galaxy-2013 and Punjab-2011) along with recommended (150-100NPkgha -1 ) and half dose (75-50NPkgha -1 ) of fertilizers. The combined application of bio-organic phosphate and the phosphorous solubilizing bacteria strain at either fertilizer level significantly improved the growth, yield parameters and productivity of both wheat cultivars compared to non-inoculated control treatments. The cultivar Punjab-2011 produced the higher chlorophyll contents, crop growth rate, and the straw yield at half dose of NP fertilizer; while Galaxy-2013, with the combined application of bio-organic phosphate and phosphorous solubilizing bacteria under recommended NP fertilizer dose. Combined over both NP fertilizer levels, the combined use of bio-organic phosphate and phosphorous solubilizing bacteria enhanced the grain yield of cultivar Galaxy-2013 by 54.3% and that of cultivar Punjab-2011 by 83.3%. The combined application of bio-organic phosphate and phosphorous solubilizing bacteria also increased the population of phosphorous solubilizing bacteria, the soil organic matter and phosphorous contents in the soil. In conclusion, the combined application of bio-organic phosphate and phosphorous solubilizing bacteria offers an eco-friendly option to harvest the better wheat yield with low fertilizer input under arid climate. Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  8. Improved solubilization of curcumin with a microemulsification formulation

    Directory of Open Access Journals (Sweden)

    ROMICĂ CREŢU

    Full Text Available Due to the large number of bioactive substances, with low and very low solubility in water, new and improved investigation methods were developed. Researches in this area have shown that lipid systems in lipophilic substances formulation increase their bioavailability and prevent or reduce the toxicological risk because most of the components involved in the formulation are of natural origin, with a structure compatible with biological membranes components. Among the lipid systems used in the leaching, transport and release of lipophilic substances there are: liposomes, solid lipid nanoparticles, double and single emulsions, autoemulsionante and auto-microemulsionante lipid systems. The last are the subject of the present research and meet specialists in concern for the harmonization of cost-benefit-risk in order to improve population health. Curcumin [(1E, 6E-1,7-bis(4-hydroxy-3-methoxyphenyl-1,6-heptadiene-3,5-dione] is a yellow pigment derived from the rhizome of the plant Curcuma Longa with phenol groups and conjugated double bounds which is unstable at light and basic pH, degrading within 30 minutes. The aim of this study is curcumin solubilization used as alimentary dye in automicroemulsionante systems. Dye/oil/surfactant/cosurfactant mixing ratio was made, based on quaternary phase diagrams. Mesofazice structures were revealed by conductivity and viscosimetric analysis. A curcumin solubilization system in aqueous medium was obtained. On the other hand, this paper studies the colour evolution of these automicroemulsionante systems comparing with hexane dye solution. The use of the chromatic attributes L*, a* and b* and L*, C* and hab, suggested by the Commission Internationale de l’Eclairage (CIE (i.e., the CIELAB system, obtained from direct transmitance measurements, which made it possible to follow the evolution of colour.

  9. P contribution derived from phosphate solubilizing microorganism activity, rock phosphate and SP-36 determination by isotope "3"2P technique

    International Nuclear Information System (INIS)

    Anggi Nico Flatian; Iswandi Anas; Atang Sutandi; Ishak

    2016-01-01

    The "3"2P isotope technique has been used to trace P nutrients in the soil and soil-plant systems. The use of the isotope "3"2P has made it possible to differentiate the P contribution derived from phosphate solubilizing microorganism activity and the fertilizer P in the soil. The aims of the study were to obtain the quantitative data of P contribution derived from phosphate-solubilizing microorganism activity (Aspergillus niger and Burkholderia cepacia), rock phosphate and SP-36 through P uptake by the plants using isotope "3"2P technique and also to study the effects on growth and production of corn plants. The results were showed that phosphate-solubilizing microorganism, rock phosphate and SP-36 was produced specific activity ("3"2P) lower than control. The results were indicated that all treatments could contribute P for the plants. The lower specific activity was caused by supply P from rock phosphate and SP-36, and also was caused by solubilized of unavailable "3"1P from PSM activity, which decreased specific activity on labeled soil. The combination of phosphate-solubilizing microorganism and SP-36 treatments produced the highest P contribution, significantly higher than control and SP-36 only. Phosphate derived from combination of microorganism and SP-36 treatments ranging from 56.06% - 68.54% after 50 days planting, after 35 days planting, 51.96% - 59.65% on stover, 46.33% - 47.70% on grain and 53.02% - 59.87% on corn cob. In addition, the treatments could significantly support the plant growth and yield. It is expressed by increased number of leave at 35 days after planting, dry weight of leave at 35 days after planting and dry weight of grain. (author)

  10. Selection and evaluation of phosphate-solubilizing bacteria from grapevine rhizospheres for use as biofertilizers

    International Nuclear Information System (INIS)

    Liu, M.; Liu, X.; Cheng, B.S.; Ma, X.L.; Lyu, X.; Zhao, X.; Ju, Y.; Min, Z.; Fang, Y.

    2016-01-01

    Phosphate-solubilizing bacteria (PSB) have the ability to solubilize insoluble phosphorus (P) and release soluble P. Extensive research has been performed with respect to PSB isolation from the rhizospheres of various plants, but little is known about the prevalence of PSB in the grapevine rhizosphere. In this study, we aimed to isolate and identify PSB from the grapevine rhizosphere in five vineyards of Northwest China, to characterize their plant-growth-promoting (PGP) traits, evaluate the effect of stress on their phosphate-solubilizing activity (PSA), and test their ability to stimulate the growth of Vitis vinifera L. cv. Cabernet Sauvignon. From the vineyard soils, 66 PSB isolates were screened, and 10 strains with high PSA were identified by 16S rRNA sequencing. Sequence analysis revealed that these 10 strains belonged to 4 genera and 5 species: Bacillus aryabhattai, B. megaterium, Klebsiella variicola, Stenotrophomonas rhizophila, and Enterobacter aerogenes. The selected PSB strains JY17 (B. aryabhattai) and JY22 (B. aryabhattai) were positive for multiple PGP traits, including nitrogen fixation and production of indole acetic acid (IAA), siderophores, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, chitinase, and protease. JY17 and JY22 showed strong PSA under stress conditions of high pH, high salt, and high temperature. Therefore, these two isolates can be used as biofertilizers in saline-alkaline soils. The inoculation with PSB significantly facilitated the growth of V. vinifera cv. Cabernet Sauvignon under greenhouse conditions. Use of these PSB as biofertilizers will increase the available P content in soils, minimize P-fertilizer application, reduce environmental pollution, and promote sustainable agriculture.

  11. Selection and evaluation of phosphate-solubilizing bacteria from grapevine rhizospheres for use as biofertilizers

    Energy Technology Data Exchange (ETDEWEB)

    Liu, M.; Liu, X.; Cheng, B.S.; Ma, X.L.; Lyu, X.; Zhao, X.; Ju, Y.; Min, Z.; Fang, Y.

    2016-07-01

    Phosphate-solubilizing bacteria (PSB) have the ability to solubilize insoluble phosphorus (P) and release soluble P. Extensive research has been performed with respect to PSB isolation from the rhizospheres of various plants, but little is known about the prevalence of PSB in the grapevine rhizosphere. In this study, we aimed to isolate and identify PSB from the grapevine rhizosphere in five vineyards of Northwest China, to characterize their plant-growth-promoting (PGP) traits, evaluate the effect of stress on their phosphate-solubilizing activity (PSA), and test their ability to stimulate the growth of Vitis vinifera L. cv. Cabernet Sauvignon. From the vineyard soils, 66 PSB isolates were screened, and 10 strains with high PSA were identified by 16S rRNA sequencing. Sequence analysis revealed that these 10 strains belonged to 4 genera and 5 species: Bacillus aryabhattai, B. megaterium, Klebsiella variicola, Stenotrophomonas rhizophila, and Enterobacter aerogenes. The selected PSB strains JY17 (B. aryabhattai) and JY22 (B. aryabhattai) were positive for multiple PGP traits, including nitrogen fixation and production of indole acetic acid (IAA), siderophores, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, chitinase, and protease. JY17 and JY22 showed strong PSA under stress conditions of high pH, high salt, and high temperature. Therefore, these two isolates can be used as biofertilizers in saline-alkaline soils. The inoculation with PSB significantly facilitated the growth of V. vinifera cv. Cabernet Sauvignon under greenhouse conditions. Use of these PSB as biofertilizers will increase the available P content in soils, minimize P-fertilizer application, reduce environmental pollution, and promote sustainable agriculture.

  12. Effect of cadmium chloride on hepatic lipid peroxidation in mice

    DEFF Research Database (Denmark)

    Andersen, H R; Andersen, O

    1988-01-01

    Intraperitoneal administration of cadmium chloride to 8-12 weeks old CBA-mice enhanced hepatic lipid peroxidation. A positive correlation between cadmium chloride dose and level of peroxidation was observed in both male and female mice. A sex-related difference in mortality was not observed...... but at a dose of 25 mumol CdCl2/kg the level of hepatic lipid peroxidation was higher in male mice than in female mice. The hepatic lipid peroxidation was not increased above the control level in 3 weeks old mice, while 6 weeks old mice responded with increased peroxidation as did 8-12 weeks old mice....... The mortality after an acute toxic dose of cadmium chloride was the same in the three age groups. Pretreatment of mice with several low intraperitoneal doses of cadmium chloride alleviated cadmium induced mortality and lipid peroxidation. The results demonstrate both age dependency and a protective effect...

  13. PEROXIDE DESTRUCTION TESTING FOR THE 200 AREA EFFLUENT TREATMENT FACILITY

    International Nuclear Information System (INIS)

    Halgren, D.L.

    2010-01-01

    The hydrogen peroxide decomposer columns at the 200 Area Effluent Treatment Facility (ETF) have been taken out of service due to ongoing problems with particulate fines and poor destruction performance from the granular activated carbon (GAC) used in the columns. An alternative search was initiated and led to bench scale testing and then pilot scale testing. Based on the bench scale testing three manganese dioxide based catalysts were evaluated in the peroxide destruction pilot column installed at the 300 Area Treated Effluent Disposal Facility. The ten inch diameter, nine foot tall, clear polyvinyl chloride (PVC) column allowed for the same six foot catalyst bed depth as is in the existing ETF system. The flow rate to the column was controlled to evaluate the performance at the same superficial velocity (gpm/ft 2 ) as the full scale design flow and normal process flow. Each catalyst was evaluated on peroxide destruction performance and particulate fines capacity and carryover. Peroxide destruction was measured by hydrogen peroxide concentration analysis of samples taken before and after the column. The presence of fines in the column headspace and the discharge from carryover was generally assessed by visual observation. All three catalysts met the peroxide destruction criteria by achieving hydrogen peroxide discharge concentrations of less than 0.5 mg/L at the design flow with inlet peroxide concentrations greater than 100 mg/L. The Sud-Chemie T-2525 catalyst was markedly better in the minimization of fines and particle carryover. It is anticipated the T-2525 can be installed as a direct replacement for the GAC in the peroxide decomposer columns. Based on the results of the peroxide method development work the recommendation is to purchase the T-2525 catalyst and initially load one of the ETF decomposer columns for full scale testing.

  14. Status and phosphorus solubilization potential of bacteria and arbuscular mycorrhizal fungi isolated from various locations of Khyber Pakhtunkhwa province

    International Nuclear Information System (INIS)

    Wahid, F.; Sharif, M.; Khan, M.

    2016-01-01

    The soils of Pakistan are alkaline calcareous in nature and its high pH makes phosphorus (P) unavailable for plants uptake. Chemical sources of P fertilizers are a costly and detrimental practice. Therefore, investigations were conducted to determine the native status of phosphate solubilizing bacteria (PSB) and arbuscular mycorrhizal fungi (AMF) in three different zones of Khyber Pakhtunkhwa province of Pakistan. In order to select the efficient PSB strains for solubility enhancement of P from rock phosphate (RP), rhizosphere soil samples were collected from irrigated and rainfed fields of maize, sorghum, pastures and vegetables. Population density of PSB ranged from 1.7*107 to 2.7*108 CFU g-1 rhizosphere soil. The bacterial strains Coccus, Streptoccocus and Bacillus sp. were identified on the basis of their microscopic, phenotypic and morphological characters. Most of the AM fungal spores identified were belonging to Glomus mosseae and Glomus intradices. A range of 02-35 spores per 20 g air dried soil were recorded. The PSB strains such as Coccus DIM7, Streptococcus PIM6 and Bacillus sp. PIS7 solubilized more P from RP than any other strain in both of the liquid and solid medium. Results show that areas under investigations are rich in P solubilizing micro flora providing a rich source for inoculum production. Moreover, the PSB strains have the capability to solubilize P from RP that can be used as biofertilizers for optimum crop production. (author)

  15. Study on mechanism of decreased lipid peroxide by low dose radiation

    International Nuclear Information System (INIS)

    Yamaoka, Kiyonori; Okazoe, Yoko; Akimaru, Kunihiro; Sato, E.F.; Utsumi, Kozo.

    1991-01-01

    We examined the effect of SOD on lipid peroxidation in biomembrane from V.E-deficient rats, in order to study the mechanism of increased SOD activities and decreased lipid peroxide by low dose irradiation. The following results were obtained. i. Active oxygen (O 2 - ) strongly enhances lipid peroxidations in biomembrane with the Fe 3+ as catalyst. ii. SOD evidently inhibits lipid peroxidations under above conditions. iii. We suggested that the effect of SOD enhanced by low dose irradiation results in inhibition of lipid peroxidation. (author)

  16. Photosystem II solubilizes as a monomer by mild detergent treatment of unstacked thylakoid membranes

    NARCIS (Netherlands)

    Dekker, Jan P.; Germano, Marta; Roon, Henny van; Boekema, Egbert J.

    2002-01-01

    We studied the aggregation state of Photosystem II in stacked and unstacked thylakoid membranes from spinach after a quick andmild solubilization with the non-ionic detergent n-dodecyl-α,D-maltoside, followed by analysis by diode-array-assisted gel filtration chromatography and electron microscopy.

  17. Singlet oxygen-mediated formation of protein peroxides within cells

    International Nuclear Information System (INIS)

    Wright, A.; Policarpio, V.

    2003-01-01

    Full text: Singlet oxygen is generated by a number of cellular, enzymatic and chemical reactions as well as by exposure to UV, or visible light in the presence of a sensitizer; as a consequence this oxidant has been proposed as a damaging agent in a number of pathologies including photo-aging and skin cancer. Proteins are major targets for singlet oxygen as a result of their abundance and high rate constants for reaction. In this study it is shown that illumination of viable, sensitizer-loaded, THP-1 (human monocyte-like) cells with visible light gives rise to intra-cellular protein-derived peroxides. The peroxide yield increases with illumination time, requires the presence of the sensitizer, is enhanced in D 2 O, and decreased by azide; these data are consistent with the mediation of singlet oxygen. The concentration of peroxides detected, which is not affected by glucose or ascorbate loading of the cells, corresponds to ca. 1.5 nmoles peroxide per 10 6 cells using rose bengal as sensitizer, or 10 nmoles per mg cell protein and account for up to ca. 15% of the O 2 consumed by the cells. Similar peroxides have been detected on isolated cellular proteins exposed to light in the presence of rose bengal and oxygen. After cessation of illumination, the cellular protein peroxide levels decreases with t 1/2 ca. 4 hrs at 37 deg C, and this is associated with increased cell lysis. Decomposition of protein peroxides formed within cells, or on isolated cellular proteins, by metal ions, gives rise to radicals as detected by EPR spin trapping. These protein peroxides, and radicals derived from them, can inactivate key cellular enzymes (including caspases, GAPDH and glutathione reductase) and induce DNA base oxidation, strand breaks and DNA-protein cross-links. These studies demonstrate that exposure of intact cells to visible light in the presence of a sensitizer gives rise to novel long-lived, but reactive, intra-cellular protein peroxides via singlet oxygen

  18. Polymer concrete composites for the production of high strength pipe and linings in high temperature corrosive environments

    Science.gov (United States)

    Zeldin, A.; Carciello, N.; Fontana, J.; Kukacka, L.

    High temperature corrosive resistant, non-aqueous polymer concrete composites are described. They comprise about 12 to 20% by weight of a water-insoluble polymer binder polymerized in situ from a liquid monomer mixture consisting essentially of about 40 to 70% by weight of styrene, about 25 to 45% by weight acrylonitrile and about 2.5 to 7.5% by weight acrylamide or methacrylamide and about 1 to 10% by weight of a crosslinking agent. This agent is selected from the group consisting of trimethylolpropane trimethacrylate and divinyl benzene; and about 80 to 88% by weight of an inert inorganic filler system containing silica sand and portland cement, and optionally Fe/sub 2/O/sub 3/ or carbon black or mica. A free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, other organic peroxides and combinations thereof to initiate crosspolymerization of the monomer mixture in the presence of said inorganic filler.

  19. Preparation and characterization of protein isolate from Yellowfin tuna Thunnus albacares roe by isoelectric solubilization/precipitation process

    Directory of Open Access Journals (Sweden)

    Hyun Ji Lee

    2016-05-01

    Full Text Available Abstract Isoelectric solubilization/precipitation (ISP processing allows selective, pH-induced water solubility of proteins with concurrent separation of lipids and removal of materials not intended for human consumption such as bone, scales, skin, etc. Recovered proteins retain functional properties and nutritional value. Four roe protein isolates (RPIs from yellowfin tuna roe were prepared under different solubilization and precipitation condition (pH 11/4.5, pH 11/5.5, pH 12/4.5 and pH 12/5.5. RPIs contained 2.3–5.0 % moisture, 79.1–87.8 % protein, 5.6–7.4 % lipid and 3.0–3.8 % ash. Protein content of RPI-1 and RPI-2 precipitated at pH 4.5 and 5.5 after alkaline solubilization at pH 11, was higher than those of RPI-3 and RPI-4 after alkaline solubilization at pH 12 (P < 0.05. Lipid content (5.6–7.4 % of RPIs was lower than that of freeze-dried concentrate (10.6 %. And leucine and lysine of RPIs were the most abundant amino acids (8.8–9.4 and 8.5–8.9 g/100 g protein, respectively. S, Na, P, K as minerals were the major elements in RPIs. SDS-PAGE of RPIs showed bands at 100, 45, 25 and 15 K. Moisture and protein contents of process water as a 2’nd byproduct were 98.9–99.0 and 1.3–1.8 %, respectively. Therefore, yellowfin tuna roe isolate could be a promising source of valuable nutrients for human food and animal feeds.

  20. A class-A GPCR solubilized under high hydrostatic pressure retains its ligand binding ability

    Science.gov (United States)

    The effect of high hydrostatic pressure (HHP) on the solubilization of a class-A G protein-coupled receptor, the silkmoth pheromone biosynthesis-activating neuropeptide receptor (PBANR), was investigated. PBANR was expressed in expresSF+ insect cells as a C-terminal fusion protein with EGFP. The mem...

  1. Synthesis and Characterization of Processable Polyaniline Salts

    International Nuclear Information System (INIS)

    Gul, Salma; Bilal, Salma; Shah, Anwar-ul-Haq Ali

    2013-01-01

    Polyaniline (PANI) is one of the most promising candidates for possible technological applications. PANI has potential applications in batteries, anion exchanger, tissue engineering, inhibition of steel corrosion, fuel cell, sensors and so on. However, its insolubility in common organic solvents limits its range of applications. In the present study an attempt has been made to synthesize soluble polyaniline salt via inverse polymerization pathway using benzoyl peroxide as oxidant and dodecylbenzenesulfonic acid (DBSA) as dopant as well as a surfactant. A mixture of chloroform and 2-butanol was used as dispersion medium for the first time. The influence of synthesis parameters such as concentration of aniline, benzoyl peroxide and DBSA on the yield and other properties of the resulting PANI salt was studied. The synthesized PANI salt was found to be completely soluble in DMSO, DMF, chloroform and in a mixture of toluene and 2-propanol. The synthesized polymer salt was also characterized with cyclic voltam-metry, SEM, XRD, UV-Vis spectroscopy and viscosity measurements. TGA was used to analyze the thermal properties of synthesized polymer. The extent of doping of the PANI salt was determined from UV-Vis spectra and TGA analysis. The activation energy for the degradation of the polymer was calculated with the help of TGA.

  2. Synthesis and characterization of completely soluble polyaniline salts via inverse emulsion polymerization using a mixture of chloroform and 2- butanol as a dispersing medium

    International Nuclear Information System (INIS)

    Gul, S.; Bilal, S.

    2011-01-01

    Polyaniline (PANI) is one of the most promising candidates for possible technological applications. PANI has potential applications in batteries, anion exchanger, tissue engineering, inhibition of steel corrosion, fuel cell, sensors and so on. However, its insolubility in common organic solvents limits its range of applications. In the present study an attempt has been made to synthesize soluble polyaniline salt via inverse polymerization pathway using benzoyl peroxide as oxidant and dodecylbenzenesulfonic acid (DBSA) as dopant as well as a surfactant. A mixture of chloroform and 2-butanol was used as dispersion medium for the first time. The influence of synthesis parameters such as concentration of aniline, benzoyl peroxide and DBSA on the yield and other properties of the resulting PANI salt was studied. The synthesized PANI salt was found to be completely soluble in DMSO, DMF, chloroform and in a mixture of toluene and 2-propanol. The synthesized polymer salt was also characterized with cyclic voltammetry, SEM, XRD, UV-Vis spectroscopy and viscosity measurements. TGA was used to analyze the thermal properties of synthesized polymer. The extent of doping of the PANI salt was determined from UV-Vis spectra and TGA analysis. The activation energy for the degradation of the polymer was calculated with the help of TGA. (author)

  3. Utilization of selected biorenewable resources: solubilization of lignocellulosics and conjugation of soybean oil

    Energy Technology Data Exchange (ETDEWEB)

    Oshel, Reed E. [Iowa State Univ., Ames, IA (United States)

    2007-01-01

    In recent years, concern has risen over the use of fossil fuels due to their contribution to global warming, and to our dependence on imports of petroleum from nations that could pose a threat to national security. As a result, it has become increasingly important to develop technologies to replace fossil fuel based products with biorenewable alternatives. In this thesis nearly quantitative solubilization of lignocellulosic materials using phosphite esters has been realized, and is presented as a potential pretreatment for production of fermentable sugars for use in manufacturing commodity chemicals, specifically ethanol. Water solubilization of lignocellulosics using phosphite esters will enhance digestibility by disrupting the lignocellulose structure, changing cellulose morphology, and cleaving some glycosidic bonds. In a second project, soybean oil, which contains un-conjugated polyunsaturated fatty acid esters, is isomerized into oil containing conjugated polyunsaturates. The process is carried out under photochemical conditions using iodine as a catalyst in a hexanes solution to achieve 99% conjugation. The resulting conjugated soybean oil is demonstrated to have enhanced drying properties for use in alkyd resins.

  4. Phylogenetic Relationship of Phosphate Solubilizing Bacteria according to 16S rRNA Genes

    Directory of Open Access Journals (Sweden)

    Mohammad Bagher Javadi Nobandegani

    2015-01-01

    Full Text Available Phosphate solubilizing bacteria (PSB can convert insoluble form of phosphorous to an available form. Applications of PSB as inoculants increase the phosphorus uptake by plant in the field. In this study, isolation and precise identification of PSB were carried out in Malaysian (Serdang oil palm field (University Putra Malaysia. Identification and phylogenetic analysis of 8 better isolates were carried out by 16S rRNA gene sequencing in which as a result five isolates belong to the Beta subdivision of Proteobacteria, one isolate was related to the Gama subdivision of Proteobacteria, and two isolates were related to the Firmicutes. Bacterial isolates of 6upmr, 2upmr, 19upmnr, 10upmr, and 24upmr were identified as Alcaligenes faecalis. Also, bacterial isolates of 20upmnr and 17upmnr were identified as Bacillus cereus and Vagococcus carniphilus, respectively, and bacterial isolates of 31upmr were identified as Serratia plymuthica. Molecular identification and characterization of oil palm strains as the specific phosphate solubilizer can reduce the time and cost of producing effective inoculate (biofertilizer in an oil palm field.

  5. Growth promotion of peanut (Arachis hypogaea L.) and maize (Zea mays L.) plants by single and mixed cultures of efficient phosphate solubilizing bacteria that are tolerant to abiotic stress and pesticides.

    Science.gov (United States)

    Anzuay, María Soledad; Ciancio, María Gabriela Ruiz; Ludueña, Liliana Mercedes; Angelini, Jorge Guillermo; Barros, Germán; Pastor, Nicolás; Taurian, Tania

    2017-06-01

    The aims of this study were, to analyze in vitro phosphate solubilization activity of six native peanut bacteria and to determine the effect of single and mixed inoculation of these bacteria on peanut and maize plants. Ability to produce organic acids and cofactor PQQ, to solubilize FePO 4 and AlPO 4 and phosphatase activity were analyzed. Also, the ability to solubilize phosphate under abiotic stress and in the presence of pesticides of the selected bacteria was determined. The effect of single and mixed bacterial inocula was analyzed on seed germination, maize plant growth and in a crop rotation plant assay with peanut and maize. The six strains produced gluconic acid and five released cofactor PQQ into the medium. All bacteria showed ability to solubilize phosphate from FePO 4 and AlPO 4 and phosphatase activity. The ability of the bacteria to solubilize tricalcium phosphate under abiotic stress and in presence of pesticides indicated encouraging results. Bacterial inoculation on peanut and maize increased seed germination, plant́s growth and P content. Phosphate solubilizing bacteria used in this study showed efficient phosphate mineralizing and solubilization ability and would be potential P-biofertilizers for peanut and maize. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Expression of a mineral phosphate solubilizing gene from Erwinia herbicola in two rhizobacterial strains.

    Science.gov (United States)

    Rodríguez, H; Gonzalez, T; Selman, G

    2001-11-30

    A genetic construction was carried out using the broad host range vector pKT230 and plasmid pMCG898, which encodes the Erwinia herbicola pyrroloquinoline quinone (PQQ) synthase, a gene involved in mineral phosphate solubilization (mps). The final construction was transformed and expressed in Escherichia coli MC1061, and the recombinant plasmids were transferred to Burkholderia cepacia IS-16 and Pseudomonas sp. PSS recipient cells by conjugation. Clones containing recombinant plasmids produced higher clearing halos in plates with insoluble phosphate as the unique (P) source, in comparison with those of strains without plasmids, demonstrating the heterologous expression of the E. herbicola gene in the recipient strains. This genetic manipulation allowed the increase in mps ability of both strains, enhancing their potentialities as growth promoters of agricultural crops. These results represent the first report on the application of the recombinant DNA methodology for the obtaining of improved phosphate solubilizing ability from rhizobacterial strains for biofertilization purposes.

  7. Mechanistic Analysis of Cocrystal Dissolution as a Function of pH and Micellar Solubilization.

    Science.gov (United States)

    Cao, Fengjuan; Amidon, Gordon L; Rodriguez-Hornedo, Nair; Amidon, Gregory E

    2016-03-07

    The purpose of this work is to provide a mechanistic understanding of the dissolution behavior of cocrystals under the influence of ionization and micellar solubilization. Mass transport models were developed by applying Fick's law of diffusion to dissolution with simultaneous chemical reactions in the hydrodynamic boundary layer adjacent to the dissolving cocrystal surface to predict the pH at the dissolving solid-liquid interface (i.e., interfacial pH) and the flux of cocrystals. To evaluate the predictive power of these models, dissolution studies of carbamazepine-saccharin (CBZ-SAC) and carbamazepine-salicylic acid (CBZ-SLC) cocrystals were performed at varied pH and surfactant concentrations above the critical stabilization concentration (CSC), where the cocrystals were thermodynamically stable. The findings in this work demonstrate that the pH dependent dissolution behavior of cocrystals with ionizable components is dependent on interfacial pH. This mass transport analysis demonstrates the importance of pH, cocrystal solubility, diffusivity, and micellar solubilization on the dissolution rates of cocrystals.

  8. Lignin-solubilizing ability of actinomycetes isolated from termite (Termitidae) gut

    International Nuclear Information System (INIS)

    Pasti, M.B.; Crawford, D.L.; Pometto, A.L. III; Nuti, M.P.

    1990-01-01

    The lignocellulose-degrading abilities of 11 novel actinomycete strains isolated from termite gut were determined and compared with that of the well-characterized actinomycete, Streptomyces viridosporus T7A. Lignocellulose bioconversion was followed by (i) monitoring the degradation of [ 14 C]lignin- and [ 14 C]cellulose-labeled phloem of Abies concolor to 14 CO 2 and 14 C-labeled water-soluble products, (ii) determining lignocellulose, lignin, and carbohydrate losses resulting from growth on a lignocellulose substrate prepared from corn stalks (Zea mays), and (iii) quantifying production of a water-soluble lignin degradation intermediate (acid-precipitable polymeric lignin). Of the assays used, total lignocellulose weight loss was most useful in determining overall bioconversion ability but not in identifying the best lignin-solubilizing strains. A screening procedure based on 14 CO 2 evolution from [ 14 C-lignin]lignocellulose combined with measurement of acid-precipitable polymeric lignin yield was the most effective in identifying lignin-solubilizing strains. For the termite gut strains, the pH of the medium showed no increase after 3 weeks of growth on lignocellulose. This is markedly different from the pattern observed with S. viridosporus T7A, which raises the medium pH considerably. Production of extracellular peroxidases by the 11 strains and S. viridosporus T7A was followed for 5 days in liquid cultures. On the basis of an increase of specific peroxidase activity in the presence of lignocellulose in the medium, the actinomycetes could be placed into the same three groups

  9. Influence of solubilizer PEG-40 hydrogenated castor oil on carbopol gels’ structural-mechanical properties

    Directory of Open Access Journals (Sweden)

    Ye. V. Gladukh

    2017-12-01

    Full Text Available Rheological properties affect all stages of the drug development – from development to production, the characteristics of the final products and stability. A lot of substances have complex rheological properties; their viscosity and elasticity can vary depending on conditions acting from the outside, such as stress, deformation, time factor and temperature. Concentration, stability and composition also significantly affect the rheological properties of drugs. One of the current trends in modern pharmacy is the development of drugs in the form of gels. The rheological properties of gels are significantly influenced by surface-active substances, stabilizers, solubilizers, stabilizing their structure. A special group of stabilizers are hydrogenated vegetable oils and their compounds with polymers, which have the ability to structure formation in interphase layers and in the volume of phases. For this purpose, PEG-40 hydrogenated castor oil is widely used. The aim of this work is to study the effect of hydrogenated castor oil, used as an emulsifier, solubilizer, viscosity modifier and solvent in the technology of semisolid dosage forms, on the structural and mechanical properties of carbopol gels. Materials and methods. 1% gel carbopol with additives PEG-40 hydrogenated castor oil in the concentration range from 1 to 5 % was investigated as experimental samples of the gel base. A 10 % propylene glycol additive was used as humectant and plasticizer. Structural and mechanical studies were carried out using a rotational viscometer «RheolabQC», Anton Paar (Austria with coaxial cylinders CCC27/SS. The graphs of the gels were automatically plotted using the computer program. Results. Analysis of the rheological parameters of the carbopol with PEG-40 hydrogenated castor oil gel base shows that the solubilizer has an active influence on the structural and mechanical properties of the base. Addition of PEG-40 GMM to the carbopol gel increases the yield

  10. Kinetics and mechanism of the furan peroxide formation in the reaction of furfural with hydrogen peroxide in the presence and absence of sodium molybdate

    International Nuclear Information System (INIS)

    Grunskaya, E.P.; Badovskaya, L.A.; Kaklyugina, T.Ya.; Poskonin, V.V.

    2000-01-01

    Kinetics of the initial stage of the reaction of furfural with hydrogen peroxide are studied in the presence of Na 2 MoO 4 in water and without catalytic additions in n-butanol. Organic peroxide having in its disposal Mo(6), which is the only product on the initial stage of the reaction, is formed since the first minutes of oxidation of furfural by hydrogen peroxide with the presence of Na 2 MoO 4 . The mechanisms of conversion of furfural in the Na 2 MoO 4 - H 2 O system and its oxidation by peroxide without sodium molybdate are discussed. Schemes of formation of furfural complexes based on the results of kinetic studies are suggested. Comparison of obtained data demonstrates that presence of the sodium molybdates in the reaction medium trends to change of reaction procedure in the hydrogen peroxide [ru

  11. Thermal cell solubilization of excess sludge; Thermischer Zellaufschluss von Ueberschussschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Duennebeil, A. [LIMUS Umwelttechnik GmbH, Berlin (Germany)

    1999-07-01

    Thermal cell solubilization of excess sludge has the following impact on subsequent digestion: cut in the mass of solids to be disposed of, enhancement of gas production and dewatering efficiency, stabilization of the digestion process, reduction of the tendency for foam formation. This does not require additional energy in an amount worth mentioning. (orig.) [German] Durch thermischen Zellaufschluss von Ueberschussschlamm wird in der nachfolgenden Faulung - die zu entsorgende Feststoffmasse reduziert - die Gasproduktion und - der Entwaesserungsgrad gesteigert sowie - der Faulbetrieb stabilisiert und - die Neigung zur Schaumbildung verringert. Dafuer ist keine nennenswerte, zusaetzliche Energie erforderlich. (orig.)

  12. Development of a new biofertilizer with a high capacity for N2 fixation, phosphate and potassium solubilization and auxin production.

    Science.gov (United States)

    Leaungvutiviroj, Chaveevan; Ruangphisarn, Pimtida; Hansanimitkul, Pikul; Shinkawa, Hidenori; Sasaki, Ken

    2010-01-01

    Biofertilizers that possess a high capacity for N(2) fixation (Azotobacter tropicalis), and consist of phosphate solubilizing bacteria (Burkhoderia unamae), and potassium solubilizing bacteria (Bacillus subtilis) and produce auxin (KJB9/2 strain), have a high potential for growth and yield enhancement of corn and vegetables (Chinese kale). For vegetables, the addition of biofertilizer alone enhanced growth 4 times. Moreover, an enhancement of growth by 7 times was observed due to the addition of rock phosphate and K-feldspar, natural mineral fertilizers, in combination with the biofertilizer.

  13. Lignin solubilization and aqueous phase reforming for the production of aromatic chemicals and hydrogen

    NARCIS (Netherlands)

    Zakzeski, J.|info:eu-repo/dai/nl/326160256; Weckhuysen, B.M.|info:eu-repo/dai/nl/285484397

    2011-01-01

    The solubilization and aqueous phase reforming of lignin, including kraft, soda, and alcell lignin along with sugarcane bagasse, at low temperatures (T≤498 K) and pressures (P≤29 bar) is reported for the first time for the production of aromatic chemicals and hydrogen. Analysis of lignin model

  14. Direct synthesis of hydrogen peroxide in a microreactor

    NARCIS (Netherlands)

    Paunovic, V.; Schouten, J.C.; Nijhuis, T.A.

    2014-01-01

    The direct synthesis of hydrogen peroxide in a microreactor is a safe and efficient process. Conventionally, hydrogen peroxide is produced using the anthraquinone autooxidation process, which is rather complex and can only be performed cost-effectively on a large scale. As a result, hydrogen

  15. Uranyl peroxide enhanced nuclear fuel corrosion in seawater.

    Science.gov (United States)

    Armstrong, Christopher R; Nyman, May; Shvareva, Tatiana; Sigmon, Ginger E; Burns, Peter C; Navrotsky, Alexandra

    2012-02-07

    The Fukushima-Daiichi nuclear accident brought together compromised irradiated fuel and large amounts of seawater in a high radiation field. Based on newly acquired thermochemical data for a series of uranyl peroxide compounds containing charge-balancing alkali cations, here we show that nanoscale cage clusters containing as many as 60 uranyl ions, bonded through peroxide and hydroxide bridges, are likely to form in solution or as precipitates under such conditions. These species will enhance the corrosion of the damaged fuel and, being thermodynamically stable and kinetically persistent in the absence of peroxide, they can potentially transport uranium over long distances.

  16. Effect of diazotrophic bacteria as phosphate solubilizing and indolic compound producers on maize plants

    Directory of Open Access Journals (Sweden)

    Mónica Del Pilar López Ortega

    2013-07-01

    Full Text Available Phosphorus is limiting for growth of maize plants, and because of that use of fertilizers like Rock Phosphate has been proposed. However, direct use of Rock Phosphate is not recommended because of its low availability, so it is necessary to improve it. In this study, a group of diazotrophic bacteria were evaluated as phosphate-solubilizing bacteria, for their production of indolic compounds and for their effects on growth of maize plants. Strains of the genera Azosporillum, Azotobacter, Rhizobium and Klebsiella, were quantitatively evaluated for solubilization of Ca3(PO42 and rock phosphate as a single source of phosphorous in SRS culture media. Additionally, the phosphatase enzyme activity was quantified at pH 5.0, 7.0 and 8.0 using p-nitrophenyl phosphate, and production of indolic compound was determined by colorimetric quantification. The effect of inoculation of bacteria on maize was determined in a completely randomized greenhouse experiment where root and shoot dry weights and phosphorus content were assessed. Results showed that strain C50 produced 107.2 mg .L-1 of available-P after 12 days of fermentation, and AC10 strain had the highest phosphatase activity at pH 8 with 12.7 mg of p-nitrophenol mL .h-1. All strains synthetized indolic compounds, and strain AV5 strain produced the most at 63.03 µg .mL-1. These diazotrophic bacteria increased plant biomass up to 39 % and accumulation of phosphorus by 10%. Hence, use of diazotrphic phosphate-solubilizing bacteria may represent an alternative technology for fertilization systems in maize plants.

  17. Effect of Combined Application of Phosphate Solubilizing Bacteria and Phosphrous Fertilizer on Growth and Yield of Sesame

    Directory of Open Access Journals (Sweden)

    S. Nikmehr

    2016-02-01

    Full Text Available Introduction: Phosphorus (P is considered to be one of the most essential macro elements required for growth and development of plants, but, due to low solubility and fixation in soils, only a small fraction of phosphorus in soil (1 ppm or 0.1% is readily available to plants. chemical fertilizers are widely used in meeting the phosphorous need of crops. However, as the fertilizer production is dependent upon fossil energy sources, continuous use of chemical fertilizers has become a matter of great concern, not only because of the diminishing availability of costly inputs but environmental concerns also. Under this background, it has obviously brought the subject of mineral phosphate solubilization in the forefront. A group of soil microorganisms is recognized to be involved in microbial phosphate solubilization mechanisms through which insoluble forms of inorganic and organic phosphates convert into soluble forms (HPO4-2 or H2PO4-. Acidification of the medium, chelating, exchange reactions and production of various acids has been discussed as the key processes attributed to the conversion. Phosphate solubilizing bacteria (PSB are a group of plant growth promoting rhizobacteria (PGPR that convert unavailable forms of phosphorus to available forms and it helps to the growth and yield of plant. The use of plant growth promoting rhizobacteria (PGPR is considered one of the most important factors increasing sesame yields. Therefore, the aim of the present study was to investigate the interactive effects of PGPR and phosphorus fertilizer on some growth parameters and components of yield and also phosphorus and Zinc uptake in sesame. Materials and Methods: In order to investigation of the effect of combined application of phosphate solubilizing bacteria and phosphorus fertilizer on growth and yield of Sesame, a greenhouse experiment was conducted as factorial based on completely randomized design with three replications including five levels of

  18. Physico Chemical Characteristic of Kappa Carrageenan Degraded Using Hydrogen Peroxide

    Directory of Open Access Journals (Sweden)

    Rizky Febriansyah Siregar

    2017-02-01

    Full Text Available AbstractKappa carrageenan is polysaccharide that widely used in food, pharmaceutical, cosmetic, textile and printing industries as coagulate agent, stabilizer and gelling agent. Hydrogen peroxide (H2O2 is strong oxidator to degrade polysaccharide. Hydrogen peroxide has some advantades such as cheap, easy to get and savety environment. Degradation method using hydrogen peroxide is a technology based on establishment radical hydoxile reactive that attack the glycosidic of polysaccharides as a result reducing in molecular weight of polysaccharide. The aims of this study were to analyze the effect of hydrogen peroxide concentration, temperature and degradation time to molecular weight of refined kappa carrageenan. Structural changes on kappa carrageenan degradation were characterized by viscometer, SEM and FTIR. Hydrogen peroxide concentration, temperature and degradation time were significantly reducing molecular weight and changes in the structural function of refined kappa carrageenan. The lowest molecular weight of refined kappa carrageenan degraded was obtained from the treatment 3% of hydrogen peroxide at temperature 80°C and degradation time for 4 hours.

  19. A Solid Binding Matrix/Mimic Receptor-Based Sensor System for Trace Level Determination of Iron Using Potential Measurements

    OpenAIRE

    Kamel, Ayman H.; Moreira, Felismina T. C.; Silva, Tamara I.; Sales, M. Goreti F.

    2011-01-01

    Iron(II)-(1,10-phenanthroline) complex imprinted membrane was prepared by ionic imprinting technology. In the first step, Fe(II) established a coordination linkage with 1,10-phenanthroline and functional monomer 2-vinylpyridine (2-VP). Next, the complex was copolymerized with ethylene glycol dimethacrylate (EGDMA) as a crosslinker in the presence of benzoyl peroxide (BPO) as an initiator. Potentiometric chemical sensors were designed by dispersing the iron(II)-imprinted polymer particles in 2...

  20. Characterization of TPS/PHBV blends prepared in the presence of maleated PHBV

    International Nuclear Information System (INIS)

    Magalhaes, Natalia F.; Andrade, Cristina T.

    2011-01-01

    Maleated derivatives of poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) were obtained in an internal mixer in the presence of maleic anhydride and benzoyl peroxide, and characterized by infrared spectroscopy. Extruded blends of cornstarch and PHBV were prepared with and without the addition of maleated PHBV. Although the X-ray diffractograms had revealed decreased crystallinity, the micrographs obtained by scanning electron microscopy indicated that the addition of the maleated derivatives led to a partial compatibilization. (author)

  1. Supra-molecular architecture in a co-crystal of the N(7)-H tautomeric form of N (6)-benzoyl-adenine with adipic acid (1/0.5).

    Science.gov (United States)

    Swinton Darious, Robert; Thomas Muthiah, Packianathan; Perdih, Franc

    2016-06-01

    The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one mol-ecule of N (6)-benzoyl-adenine (BA) and one half-mol-ecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. The N (6)-benzoyl-adenine mol-ecule crystallizes in the N(7)-H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intra-molecular N-H⋯O hydrogen bonding between the carbonyl (C=O) group and the N(7)-H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7) ring motif. The two carboxyl groups of adipic acid inter-act with the Watson-Crick face of the BA mol-ecules through O-H⋯N and N-H⋯O hydrogen bonds, generating an R 2 (2)(8) ring motif. The latter units are linked by N-H⋯N hydrogen bonds, forming layers parallel to (10-5). A weak C-H⋯O hydrogen bond is also present, linking adipic acid mol-ecules in neighbouring layers, enclosing R (2) 2(10) ring motifs and forming a three-dimensional structure. C=O⋯π and C-H⋯π inter-actions are also present in the structure.

  2. Impact of sediments resuspension on metal solubilization and water quality during recurrent reservoir sluicing management

    Energy Technology Data Exchange (ETDEWEB)

    Frémion, Franck; Courtin-Nomade, Alexandra [Groupement de Recherche Eau Sol Environnement, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges Cedex (France); Bordas, François, E-mail: francois.bordas@unilim.fr [Groupement de Recherche Eau Sol Environnement, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges Cedex (France); Lenain, Jean-François [Groupement de Recherche Eau Sol Environnement, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges Cedex (France); Jugé, Philippe [CETU – ELMIS Ingénieries, Université François Rabelais, , 60 Rue du Plat d' Étain, 37000 Tours (France); Kestens, Tim [EDF – DPIH, Unité de Production Centre, 19 bis avenue de la Révolution, BP 406, 87012 Limoges Cedex (France); Mourier, Brice [Groupement de Recherche Eau Sol Environnement, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges Cedex (France)

    2016-08-15

    In dam contexts, sluicing operations can be performed to reestablish sediments continuity, as proposed by the EU Water Framework Directive, as well as to preserve the reservoirs' water storage capacity. Such management permits the rapid release of high quantities of reservoir sediments through the opening of dam bottom valves. This work aims to study the impact of such operation on the evolution of environmental physicochemical conditions notably changes in dissolved metallic elements concentrations (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) through field and laboratory investigations. Results were interpreted in terms of concentrations and fluxes, and compared with data collected on an annual basis regarding both suspended matter and metallic elements. The release of high quantities of sediments (4,500 tons dry weight in 24 h), with concentrations representing up to 300 times the inter-annual mean suspended sediments discharge, significantly modified water parameters, notably solid/liquid (S/L) ratio, pH and redox conditions. Despite the fact that they are mainly trapped in stable phases, a clear increase of the solubilized metals content was measured, representing up to 60 times the maximum values of current exploitation. This solubilization is related to desorption phenomena from sediments through changes in chemical equilibriums as highlighted by laboratory characterizations and experiments. These chemical modifications are mainly attributed to S/L ratio variations. Indeed, the low S/L ratios (≤ 1.3 g·L{sup −1}) measured in situ are typically the ones for which metals solubilization is the highest, as shown by laboratory experiments. Additional thermodynamic modeling highlighted that the decrease in pH measured during the operation favors the release of the free forms of metallic elements (Al and Cu), and decreases the OM complexation influence. These changes, either in term of physical conditions or speciation, increasing metals long term

  3. Tooth bleaching using peroxide-containing agents: current status of safety issues.

    Science.gov (United States)

    Li, Y

    1998-08-01

    During the last 10 years, at-home tooth bleaching using peroxide-containing agents has quickly become well accepted. It is one of the most popular cosmetic dental procedures for whitening teeth. Although there are few disputes regarding their efficacy, concerns and debates have continued regarding the safety of peroxide-containing tooth bleaching agents. Potential carcinogenicity and genotoxicity of the peroxides used in bleaching agents are the two most persistent and controversial issues. This article reviews and discusses available information on carcinogenicity and genotoxicity of hydrogen peroxide and the potential risks associated with the use of peroxide-containing bleaching agents. Clinical studies reported after the 1996 international symposium on responses of oral tissues to peroxide-containing bleaching agents are also reviewed. Overall evidence supports the conclusion that the proper use of peroxide-containing at-home tooth bleaching agents is safe. However, potential adverse effects may occur in inappropriate applications, abuses, or the use of inappropriate products. At-home tooth bleaching should be monitored by dental professionals to maximize the benefits while minimizing potential risks.

  4. Phosphate solubilization and chromium (VI) remediation potential of Klebsiella sp. strain CPSB4 isolated from the chromium contaminated agricultural soil.

    Science.gov (United States)

    Gupta, Pratishtha; Kumar, Vipin; Usmani, Zeba; Rani, Rupa; Chandra, Avantika

    2018-02-01

    In this study, an effort was made to identify an efficient phosphate solubilizing bacterial strain from chromium contaminated agricultural soils. Based on the formation of a solubilized halo around the colonies on Pikovskaya's agar amended with chromium (VI), 10 strains were initially screened out. Out of 10, strain CPSB4, which showed significantly high solubilization zone at different chromium concentrations, was selected for further study. The strain CPSB4 showed significant plant growth promotion traits with chromium (VI) stress under in-vitro conditions in broth. The plant growth promotion activities of the strain decreased regularly, but were not completely lost with the increase in concentration of chromium up to 200 mg L -1 . On subjected to FT-IR analysis, the presence of the functional group, indicating the organic acid aiding in phosphate solubilization was identified. At an optimal temperature of 30  ° C and pH 7.0, the strain showed around 93% chromium (VI) reduction under in-vitro conditions in broth study. In soil condition, the maximum chromium (VI) reduction obtained was 95% under in-vitro conditions. The strain CPSB4 was identified as Klebsiella sp. on the basis of morphological, biochemical and 16S rRNA gene sequencing. This study shows that the diverse role of the bacterial strain CPSB4 would be useful in the chromium contaminated soil as a good bioremediation and plant growth promoting agent as well. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Chromium-induced accumulation of peroxide content, stimulation of ...

    African Journals Online (AJOL)

    Chromium (Cr)-induced oxidative damage and changes in contents of chlorophyll, protein, peroxide and malondialdehyde (MDA) and activities of enzymatic antioxidants were investigated in 4-day-old green gram (Vigna radiata L. cv. Wilczek) seedlings. Cr increased the contents of peroxide and MDA but decreased the ...

  6. Propylene epoxydation with hydrogen peroxide in acidic conditions

    NARCIS (Netherlands)

    Kertalli, E.; Rijnsoever, L.S.; Paunovic, V.; Schouten, J.C.; Neira d'Angelo, M.F.; Nijhuis, T.A.

    2016-01-01

    In the present work, the epoxidation of propylene with hydrogen peroxide in the presence of acids and halides is studied. The presence of acids and halides is indispensable for increasing the selectivity of the direct synthesis of hydrogen peroxide, the first step of the direct propylene oxide

  7. Solubilization of advanced ceramic materials controlled by chemical analysis by means of atomic absorption spectroscopy

    International Nuclear Information System (INIS)

    Amarante Junior, A.

    1992-01-01

    This paper purpose is to show the techniques used in chemical analysis laboratory at Escola SENAI Mario Amato in the ceramic nucleus for opening and solubilization of Advanced Ceramic materials, where the elements in its majority are determined for atomic absorption spectroscopy. (author)

  8. Inhibition of liver fibrosis by solubilized coenzyme Q10: Role of Nrf2 activation in inhibiting transforming growth factor-β1 expression

    International Nuclear Information System (INIS)

    Choi, Hoo-Kyun; Pokharel, Yuba Raj; Lim, Sung Chul; Han, Hyo-Kyung; Ryu, Chang Seon; Kim, Sang Kyum; Kwak, Mi Kyong; Kang, Keon Wook

    2009-01-01

    Coenzyme Q10 (CoQ10), an endogenous antioxidant, is important in oxidative phosphorylation in mitochondria. It has anti-diabetic and anti-cardiovascular disease effects, but its ability to protect against liver fibrosis has not been studied. Here, we assessed the ability of solubilized CoQ10 to improve dimethylnitrosamine (DMN)-induced liver fibrogenesis in mice. DMN treatments for 3 weeks produced a marked liver fibrosis as assessed by histopathological examination and tissue 4-hydroxyproline content. Solubilized CoQ10 (10 and 30 mg/kg) significantly inhibited both the increases in fibrosis score and 4-hydroxyproline content induced by DMN. Reverse transcription-polymerase chain reaction and Western blot analyses revealed that solubilized CoQ10 inhibited increases in the transforming growth factor-β1 (TGF-β1) mRNA and α-smooth muscle actin (α-SMA) protein by DMN. Interestingly, hepatic glutamate-cysteine ligase (GCL) and glutathione S-transferase A2 (GSTA2) were up-regulated in mice treated with CoQ10. Solubilized CoQ10 also up-regulated antioxidant enzymes such as catalytic subunits of GCL and GSTA2 via activating NF-E2 related factor2 (Nrf2)/antioxidant response element (ARE) in H4IIE hepatoma cells. Moreover, CoQ10's inhibition of α-SMA and TGF-β1 expressions disappeared in Nrf2-null MEF cells. In contrast, Nrf2 overexpression significantly decreased the basal expression levels of α-SMA and TGF-β1 in Nrf2-null MEF cells. These results demonstrated that solubilized CoQ10 inhibited DMN-induced liver fibrosis through suppression of TGF-β1 expression via Nrf2/ARE activation.

  9. A survey of chemicals inducing lipid peroxidation in biological systems.

    Science.gov (United States)

    Kappus, H

    1987-01-01

    A great number of drugs and chemicals are reviewed which have been shown to stimulate lipid peroxidation in any biological system. The underlying mechanisms, as far as known, are also dealt with. Lipid peroxidation induced by iron ions, organic hydroperoxides, halogenated hydrocarbons, redox cycling drugs, glutathione depleting chemicals, ethanol, heavy metals, ozone, nitrogen dioxide and a number of miscellaneous compounds, e.g. hydrazines, pesticides, antibiotics, are mentioned. It is shown that lipid peroxidation is stimulated by many of these compounds. However, quantitative estimates cannot be given yet and it is still impossible to judge the biological relevance of chemical-induced lipid peroxidation.

  10. Peroxides and radiation impairment of oxidative phosphorylation

    Energy Technology Data Exchange (ETDEWEB)

    Dovgii, I E; Akoev, I G

    1975-09-01

    An increase in the peroxidase activity of the mitochondria and a simultaneous rise in the amount of peroxide compounds, which are half lipid-like substances, are detected within the first 10 minutes after irradiation (1000 r). A mechanism of radiation impairment of oxidative phosphorylation is connected with the penetration of its inhibitors to the mitochondria due to the disturbed permeability of membranes affected by peroxides.

  11. A hydrogen peroxide sensor for exhaled breath measurement

    NARCIS (Netherlands)

    Dam, T.V.A.; Olthuis, Wouter; Bergveld, Piet; van den Berg, Albert

    2004-01-01

    An increase in produced hydrogen peroxide concentration in exhaled breath (EB) of patients, who suffer from some diseases related to lung function, has been observed and considered as a reliable indicator of lung diseases. In the EB of these patients, hydrogen peroxide is present in the vapour phase

  12. A hydrogen peroxide sensor for exhaled breath measurement

    NARCIS (Netherlands)

    Dam, T.V.A.; Olthuis, Wouter; Bergveld, Piet

    2005-01-01

    An increase in hydrogen peroxide concentration in exhaled breath (EB) of patients, who suffer from some diseases related to the lung function, has been observed and considered as a reliable indicator of lung diseases. In the EB of these patients, hydrogen peroxide is present in the vapour phase

  13. Solubilization of immune complexes in complement factor deficient sera and the influence of temperature, ionic strength and divalent cations on the solubilization reaction

    DEFF Research Database (Denmark)

    Baatrup, Gunnar; Petersen, Ivan; Svehag, Svend-Erik

    1984-01-01

    The complement-mediated solubilization (CMS) of immune complexes (IC) and the initial kinetics (IKS) of this reaction in human sera depleted of or deficient in C2, C3, C8, factors B, P and I were investigated. Sera depleted of B or P and those lacking native C3 or factor I showed virtually no CMS......M. Chelation of Ca2+ in serum by Mg2+-ethylene glycol tetraacetic acid reduced the CMS capacity by up to 50% and the IKS was markedly retarded. Varying the Zn2+ or Mn2+ ion concentrations in serum influenced neither the IKS nor the CMS capacity....

  14. Photo-oxidation of histidine peptides yields high concentrations of unstable peroxides

    International Nuclear Information System (INIS)

    Policarpio, V.V.; Hawkins, C.L.; Davies, M.J.

    2003-01-01

    Oxidation of proteins by UV, and visible light in the presence of sensitizers, results in side chain modification as well as aggregation and fragmentation. In particular, singlet oxygen has been reported to oxidize Met, Trp, Tyr, Cys and His side chains in a selective manner. In this study the oxidation of histidine and its derivatives, and His-containing peptides is examined using a range of sensitizers, to determine whether peroxides are major intermediates, and the mechanism of formation of these species. Visible light-sensitised oxidation of Gly-His-Gly in the presence of oxygen and rose bengal gives unstable substrate-derived peroxides with the peroxide yield increasing with increasing photolysis time. Similar behaviour was detected with other photosensitizers, though the peroxide yields varied with the sensitizer at identical concentrations with rose bengal > aluminium phthalocyanine > hematoporphyrin IX > zinc phthalocyanine > tetrakisporphine. The peroxide yield was decreased in the presence of azide and enhanced when deuterium oxide was employed as the solvent, consistent with peroxide formation being singlet oxygen mediated. Experiments using anoxic conditions gave low yields of peroxides confirming the oxygen-dependence of these reactions. HPLC analysis showed rapid loss of the parent peptide, with subsequent formation of both stable and unstable products; these are currently being characterized by MS and NMR. Similar behavior has been observed with other His derivatives. The yield of singlet oxygen formed in these reactions has been estimated using a bleaching assay (N, N-dimethyl-4-nitrosoaniline). Quantification of singlet oxygen formation and Gly-His-Gly derived peroxide during rose bengal-mediated photooxidation indicated a conversion efficiency of the initial singlet oxygen into substrate-derived peroxides of ca. 75% indicating that peroxide formation is a highly efficient and major reaction pathway

  15. The evaluation of hydrogen peroxide bleaching of Gonometa ...

    African Journals Online (AJOL)

    The effect of hydrogen peroxide bleaching on Gonometa postica silk and the influence that temperature, pH and time duration had on hydrogen peroxide release , colour change, breaking load and stiffness were determined. The best bleaching (81 delta E) of the Gonometa postica silk fabric was obtained with 60 minutes ...

  16. Extraction of hafnium by 1-phenyl-3-methyl-4-benzoyl-5-pyralozone from aqueous-alcoholic solutions

    International Nuclear Information System (INIS)

    Hala, J.; Prihoda, J.

    1975-01-01

    Extraction of hafnium by 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HL) in benzene, toluene, chloroform and tetrachloromethane from aqueous-alcoholic solutions of the formal acidity of 2M-HClO 4 was studied. Methyl, ethyl, n- and isopropyl, tert-butyl and allyl alcohol as well as ethylene glycol monomethyl ether and propylene glycol were used as organic components of the mixed aqueous-organic phase. Their presence in some cases resulted in a synergic increase in the distribution ratio of hafnium. The increase is interpreted using the results of a slope analysis and measurements of the alcohol distribution and the relative permittivity of the organic phase. It is suggested that HfL 4 molecules were solvated by alcohol molecules in the organic phase. At high alcohol concentration synergism changed into antagonism. This was caused by changes in the distribution of HL and its interaction with the alcohol in the organic phase. (author)

  17. Isolation and identification of phosphate solubilizer Azospirillum, Bacillus and Enterobacter strains by 16SrRNA sequence analysis and their effect on growth of wheat (Triticum aestivum L.)

    NARCIS (Netherlands)

    Tahir, M.; Mirza, M.S.; Zaheer, A.; Rocha Dimitrov, M.; Smidt, H.; Hameed, S.

    2013-01-01

    The aim of the present study was to isolate phosphate solubilizing bacteria from wheat rhizosphere and investigate their potential for plant growth promotion. Three phosphate solubilizing bacterial strains were isolated by serial dilution method from the rhizosphere of wheat grown under wheat-cotton

  18. Sex-related differences in NADPH-dependent lipid peroxidation induced by cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Masao; Nagai, Yasushi

    1986-10-01

    Male and female rats were dosed once a day for 2 days with injections of 1.5 mg Cd/kg. Formation of thiobarbituric acid reactive substances (TBA-RS) was significantly increased in male rat liver but not in the females. NADPH-dependent lipid peroxidation in vitro in microsomes derived from untreated rat liver was greater in males than in females. Furthermore, addition of cadmium (Cd) to microsomes isolated from male rat liver produced a dose-dependent potentiation of NADPH-dependent lipid peroxidation from low concentrations of CD. In microsomes derived from females a significant increase in lipid peroxidation was observed only at high Cd concentrations. NADPH-dependent lipid peroxidation enhanced by Cd was greater in the males than in the females. These data suggest that a sex-related difference in the ability of Cd to induce lipid peroxidation in vivo in rat liver appears to be mediated partly through differences in hepatic microsomal NADPH-dependent lipid peroxidation.

  19. Changes of Phosphate Solubilizing Bacteria Population on Paddy Field with Intensive Farming became Sustainable Organic Farming System

    Directory of Open Access Journals (Sweden)

    Dermiyati

    2009-05-01

    Full Text Available The research aimed to study the change of population of phosphate solubilizing microorganisms according to the application time of bokashi which were applied continously on organic paddy rice fields since years of 2000 up to 2006. The research was conducted in a Randomized Completely Block Design in four replicates. The treatments were without bokashi (control; with intensively application of NPK fertilizers, bokashi application for 3 planting seasons (12 t ha-1, bokashi application for 4 planting seasons (16 t ha-1, bokashi application for 7 planting seasons (28 t ha-1, and bokashi application for 9 planting seasons (36 t ha-1. The results showed that the population of phosphate solubilizing microorganisms were not affected by continously applied of bokashi and did not have correlations to organic carbon, total nitrogen, ratio C/N, soil pH, and soil water content. However, the phosphate solubilizing microorganisms had played a role in the availability of the soil available-P which were shown by increasing of paddy yields year by year, although the contribution of soil phosphorus from bokashi is a relatively low. Yet, the bokashi application on the organic paddy fields did not increase the soil availble-P because most of the P which was absorbed by the plants coming from residual P fertilizers either from bokashi or SP-36 which were intensevely given before.

  20. GENETIC VARIABILITY OF SUGARCANE-ASSOCIATED DIAZOTROPHIC BACTERIA CAPABLE OF INORGANIC PHOSPHATE SOLUBILIZING

    OpenAIRE

    Lira-Cadete, Luana; Barbosa de Farias, Andreza Raquel; de Souza Ramos, Andresa Priscila; da Costa, Diogo Paes; Freire, Fernando Jose; Kuklinsky-Sobral, Julia

    2013-01-01

    The sugarcane is a culture of great importance for the Brazilian agriculture. Every year this culture consumes great amounts of nitrogen and phosphate fertilizers. However, the use of plant growth-promoting bacteria can reduce the use of the chemical fertilizers, contributing to the economy and the environment conservation. So, the goal of this study was to select sugarcane-associated diazotrophic bacteria able to solubilize inorganic phosphate and to evaluate the genetic diversity of these b...

  1. Acid phosphatase and lipid peroxidation in human cataractous lens epithelium

    Directory of Open Access Journals (Sweden)

    Vasavada Abhay

    1993-01-01

    Full Text Available The anterior lens epithelial cells undergo a variety of degenerative and proliferative changes during cataract formation. Acid phosphatase is primarily responsible for tissue regeneration and tissue repair. The lipid hydroperoxides that are obtained by lipid peroxidation of polysaturated or unsaturated fatty acids bring about deterioration of biological membranes at cellular and tissue levels. Acid phosphatase and lipid peroxidation activities were studied on the lens epithelial cells of nuclear cataract, posterior subcapsular cataract, mature cataract, and mixed cataract. Of these, mature cataractous lens epithelium showed maximum activity for acid phosphatase (516.83 moles of p-nitrophenol released/g lens epithelium and maximum levels of lipid peroxidation (86.29 O.D./min/g lens epithelium. In contrast, mixed cataractous lens epithelium showed minimum activity of acid phosphatase (222.61 moles of p-nitrophenol released/g lens epithelium and minimum levels of lipid peroxidation (54.23 O.D./min/g lens epithelium. From our study, we correlated the maximum activity of acid phosphatase in mature cataractous lens epithelium with the increased areas of superimposed cells associated with the formation of mature cataract. Likewise, the maximum levels of lipid peroxidation in mature cataractous lens epithelium was correlated with increased permeability of the plasma membrane. Conversely, the minimum levels of lipid peroxidation in mixed cataractous lens epithelium makes us presume that factors other than lipid peroxidation may also account for the formation of mixed type of cataract.

  2. Lipid Peroxidation: Pathophysiology and Pharmacological Implications in the Eye

    Directory of Open Access Journals (Sweden)

    Ya Fatou eNjie-Mbye

    2013-12-01

    Full Text Available Oxygen-derived free radicals such as hydroxyl and hydroperoxyl species have been shown to oxidize phospholipids and other membrane lipid components leading to lipid peroxidation. In the eye, lipid peroxidation has been reported to play an important role in degenerative ocular diseases (age-related macular degeneration, cataract, glaucoma, diabetic retinopathy. Indeed, ocular tissues are prone to damage from reactive oxygen species due to stress from constant exposure of the eye to sunlight, atmospheric oxygen and environmental chemicals. Furthermore, free radical catalyzed peroxidation of long chain polyunsaturated acids (LCPUFAs such as arachidonic acid and docosahexaenoic acid leads to generation of LCPUFA metabolites including isoprostanes and neuroprostanes that may further exert pharmacological/toxicological actions in ocular tissues. Evidence from literature supports the presence of endogenous defense mechanisms against reactive oxygen species in the eye, thereby presenting new avenues for the prevention and treatment of ocular degeneration. Hydrogen peroxide (H2O2 and synthetic peroxides can exert pharmacological and toxicological effects on tissues of the anterior uvea of several mammalian species. There is evidence suggesting that the retina, especially retinal ganglion cells can exhibit unique characteristics of antioxidant defense mechanisms. In the posterior segment of the eye, H2O2 and synthetic peroxides produce an inhibitory action on glutamate release (using [3H]-D-aspartate as a marker, in vitro and on the endogenous glutamate and glycine concentrations in vivo. In addition to peroxides, isoprostanes can elicit both excitatory and inhibitory effects on norepinephrine (NE release from sympathetic nerves in isolated mammalian iris ciliary bodies. Whereas isoprostanes attenuate dopamine release from mammalian neural retina, in vitro, these novel arachidonic acid metabolites exhibit a biphasic regulatory effect on glutamate release

  3. Protective mechanisms against peptide and protein peroxides generated by singlet oxygen

    DEFF Research Database (Denmark)

    Morgan, Philip E; Dean, Roger T; Davies, Michael Jonathan

    2004-01-01

    or detoxify such peroxides. It is shown that catalase, horseradish peroxidase, and Cu/Zn superoxide dismutase do not react rapidly with these peroxides. Oxymyoglobin and oxyhemoglobin, but not the met (Fe3+) forms of these proteins, react with peptide but not protein, peroxides with oxidation of the heme iron...

  4. Degradation/solubilization of Chinese lignite by Penicillium sp. P6

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, H.L.; Yang, J.S.; Wang, F.Q.; Chen, W.X. [China Agricultural University, Beijing (China). Key Laboratory of Agro-Microbial Resource and Application, Ministry of Agrio, College of Biological Science

    2006-01-15

    Penicillium sp. P6, isolated from coal mine soil at the Qiantong colliery Liaoning Province, Northeast China, can degrade Chinese lignite in 36 h on a plate colony and in 48 h using a 4-day cultured cell-free filtrate. Results of elemental analysis and IR spectrometry indicated that solubilized products exhibited some alterations in comparison to the original lignite. The amount of fulvic acid extracted from the biodegraded lignite was high, and the molecular distribution of the humic acids from biodegraded lignite changed distinctively in comparison to which extracted from the control lignite, possibly due to the depolymerization associated with fungal biodegradation.

  5. Synthesis of Some New Quaternary Ammonium Compounds Evaluation of their Surface properties and Solubilization Activity

    International Nuclear Information System (INIS)

    Ismail, D.A.; Mohamed, A.S.; Mohamed, M.Z.

    2004-01-01

    Four cationic surfactants were prepared by condensing fatty acid methyl diethanolamine derivatives (C 6 , C I0 , C I2 , C I8 ) with stoichiometric amounts of trimethyl chlorosilane. The surface properties and parameters were investigated to find the relationship between the structure of the hydrophobic portion of such compounds and their efficiency toward solubilization. The properties studied included surface excess concentration (Γ m ax), critical micelle concentration (cmc). free energy of micellization (ΔG ο m ic) and adsorption (ΔG ο a ds) in addition to the surface tension (γ c mc) at cmc and effectiveness (Π c mc). The values of Γ m ax, ΔG ο mic and ΔG ο a ds were found to increase with increasing number of chain length. while cmc and minimum surface area occupied by one molecule (A m in) were decreased. Solubilization effect of these surfactants on paraffin oil as a non polar solubilizate and biodegradability were studied

  6. Quantifying intracellular hydrogen peroxide perturbations in terms of concentration

    Directory of Open Access Journals (Sweden)

    Beijing K. Huang

    2014-01-01

    Full Text Available Molecular level, mechanistic understanding of the roles of reactive oxygen species (ROS in a variety of pathological conditions is hindered by the difficulties associated with determining the concentration of various ROS species. Here, we present an approach that converts fold-change in the signal from an intracellular sensor of hydrogen peroxide into changes in absolute concentration. The method uses extracellular additions of peroxide and an improved biochemical measurement of the gradient between extracellular and intracellular peroxide concentrations to calibrate the intracellular sensor. By measuring peroxiredoxin activity, we found that this gradient is 650-fold rather than the 7–10-fold that is widely cited. The resulting calibration is important for understanding the mass-action kinetics of complex networks of redox reactions, and it enables meaningful characterization and comparison of outputs from endogenous peroxide generating tools and therapeutics across studies.

  7. Solubilization of glycoproteins of envelope viruses by detergents

    International Nuclear Information System (INIS)

    Berezin, V.E.; Zaides, V.M.; Artamsnov, A.F.; Isaeva, E.S.; Zhdanov, V.M.

    1986-01-01

    The action of a number of known ionic and nonionic detergents, as well as the new nonionic detergent MESK, on envelope viruses was investigated. It was shown that the nonionic detergents MESK, Triton X-100, and octyl-β-D-glucopyranoside selectively solubilize the outer glycoproteins of the virus particles. The nonionic detergent MESK has the mildest action. Using MESK, purified glycoproteins of influenza, parainfluenza, Venezuelan equine encephalomyelitis, vesicular stomatitis, rabies, and herpes viruses were obtained. The procedure for obtaining glycoproteins includes incubation of the virus suspension with the detergent MESK, removal of subvirus structures by centrifuging, and purification of glycoproteins from detergents by dialysis. Isolated glycoproteins retain a native structure and biological activity and possess high immunogenicity. The detergent MESK is promising for laboratory tests and with respect to the production of subunit vaccines

  8. Expression of zinc transporter genes in rice as influenced by zinc-solubilizing Enterobacter cloacae strain ZSB14

    Directory of Open Access Journals (Sweden)

    Selvaraj eKrithika

    2016-04-01

    Full Text Available Zinc (Zn deficiency in major food crops has been considered as an important factor affecting the crop production and subsequently the human health. Rice (Oryza sativa is sensitive to Zn deficiency and thereby causes malnutrition to most of the rice-eating Asian populations. Application of zinc solubilizing bacteria (ZSB could be a sustainable agronomic approach to increase the soil available Zn which can mitigate the yield loss and consequently the nutritional quality of rice. Understanding the molecular interactions between rice and unexplored ZSB is useful for overcoming Zn deficiency problems. In the present study, the role of zinc solubilizing bacterial strain Enterobacter cloacae strain ZSB14 on regulation of Zn-regulated transporters and iron (Fe-regulated transporter-like protein (ZIP genes in rice under iron sufficient and deficient conditions was assessed by quantitative real-time reverse transcription PCR. The expression patterns of OsZIP1, OsZIP4 and OsZIP5 in root and shoot of rice were altered due to the Zn availability as dictated by Zn sources and ZSB inoculation. Fe sufficiency significantly reduced the root and shoot OsZIP1 expression, but not the OsZIP4 and OsZIP5 levels. Zinc oxide in the growth medium up-regulated all the assessed ZIP genes in root and shoot of rice seedlings. When ZSB was inoculated to rice seedlings grown with insoluble zinc oxide in the growth medium, the expression of root and shoot OsZIP1, OsZIP4 and OsZIP5 was reduced. In the absence of zinc oxide, ZSB inoculation up-regulated OsZIP1 and OsZIP5 expressions. Zinc nutrition provided to the rice seedling through ZSB-bound zinc oxide solubilization was comparable to the soluble zinc sulphate application which was evident through the ZIP genes’ expression and the Zn accumulation in root and shoot of rice seedlings. These results demonstrate that zinc solubilizing bacteria could play a crucial role in zinc fertilization and fortification of rice.

  9. A biomaterial composed of collagen and solubilized elastin enhances angiogenesis and elastic fiber formation without calcification.

    NARCIS (Netherlands)

    Daamen, W.F.; Nillesen, S.T.M.; Wismans, P.G.P.; Reinhardt, D.; Hafmans, T.G.M.; Veerkamp, J.H.; Kuppevelt, A.H.M.S.M. van

    2008-01-01

    Elastin is the prime protein in elastic tissues that contributes to elasticity of, for example, lung, aorta, and skin. Upon injury, elastic fibers are not readily replaced, which hampers tissue regeneration. Incorporation of solubilized elastin (hydrolyzed insoluble elastin fibers or elastin

  10. Synthesis of unstable cyclic peroxides for chemiluminescence studies

    Energy Technology Data Exchange (ETDEWEB)

    Bartoloni, Fernando H.; Oliveira, Marcelo A. de; Augusto, Felipe A.; Ciscato, Luiz Francisco M.L.; Bastos, Erick L.; Baader, Wilhelm J., E-mail: wjbaader@iq.usp.br [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Dept. de Quimica Fundamental

    2012-11-15

    Cyclic four-membered ring peroxides are important high-energy intermediates in a variety of chemi and bioluminescence transformations. Specifically, a-peroxy lactones (1,2-dioxetanones) have been considered as model systems for efficient firefly bioluminescence. However, the preparation of such highly unstable compounds is extremely difficult and, therefore, only few research groups have been able to study the properties of these substances. In this study, the synthesis, purification and characterization of three 1,2-dioxetanones are reported and a detailed procedure for the known synthesis of diphenoyl peroxide, another important model compound for the chemical generation of electronically excited states, is provided. For most of these peroxides, the complete spectroscopic characterization is reported here for the first time. (author)

  11. Characterization of Phosphate Solubilizing Bacteria in Sediments from a Shallow Eutrophic Lake and a Wetland: Isolation, Molecular Identification and Phosphorus Release Ability Determination

    Directory of Open Access Journals (Sweden)

    Jie Tang

    2010-11-01

    Full Text Available The transformation of phosphorus (P is a major factor of lake eutrophication, and phosphate releasing bacteria play an important role in the release process. Experiments were conducted to investigate P content and characterize phosphate solubilizing bacterial composition at the molecular level in a shallow eutrophic lake and a wetland. Results showed that P concentrations were relatively high and derived from agricultural runoff and domestic or industrial pollution. Enumeration and molecular identification of these strains indicated that these bacterial groups were abundant in the ecosystem and various kinds of bacteria participated in the phosphorus release process. Twelve phosphate solubilizing bacteria, including eight organic P-solubilizing bacteria (OPBs and four inorganic P-solubilizing bacteria (IPBs, which belonged to three different families, were isolated and identified. Cupriavidus basilensis was found for the first time to have the ability to mineralize organic P (OP. Laboratory tests on P release ability revealed that IPBs were more effective at releasing P than OPBs. The most efficient IPB strain could accumulate over 170 mg·L-1 orthophosphate, while the equivalent OPB strain only liberated less than 4 mg·L-1 orthophosphate in liquid culture. The results obtained from this investigation should help clarify the roles of microorganisms in aquatic systems and the mechanisms of eutrophication.

  12. Isolation of plant Photosystem II complexes by fractional solubilization

    Directory of Open Access Journals (Sweden)

    Patrycja eHaniewicz

    2015-12-01

    Full Text Available PSII occurs in different forms and supercomplexes in thylakoid membranes. Using a transplastomic strain of Nicotiana tabacum histidine tagged on the subunit PsbE, we have previously shown that a mild extraction protocol with β-dodecylmaltoside enriches PSII characteristic of lamellae and grana margins. Here, we characterize residual granal PSII that is not extracted by this first solubilization step. Using affinity purification, we demonstrate that this PSII fraction consists of PSII-LHCII mega- and supercomplexes, PSII dimers and PSII monomers, which were separated by gel filtration and functionally characterized. Our findings represent an alternative demonstration of different PSII populations in thylakoid membranes, and they make it possible to prepare PSII-LHCII supercomplexes in high yield.

  13. Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphide

    International Nuclear Information System (INIS)

    Losev, Yu.P.; Amadyan, M.G.; Oganesyan, N.M.; Fedulov, A.S.; Abramyan, A.K.; Shagoyan, A.G.; Khachkavanktsyan, A.S.

    1999-01-01

    Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphade has been studied. Rats were exposed to X-rays in doses 4,8 and 5,25 Gy. Lipid peroxidation was analysed in blood plasma, membranes of erythrocytes and homogenates of liver and spleen tissues of rats. Polydisulphide of gallic acid was used as inhibitor of lipid peroxidation because of its effective antioxidant properties as have been reported previously. It has been demonstrated that gallic disulphide exhibited high inhibition efficiency in conditions of radiation-induced lipid peroxidation due to the effect of intra-molecular synergism

  14. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    International Nuclear Information System (INIS)

    De, A.K.; Ghosh, J.J.; Mandal, T.K.

    1993-01-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation

  15. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    Energy Technology Data Exchange (ETDEWEB)

    De, A. K.; Ghosh, J. J.; Mandal, T. K. [University College of Science, Department of Biochemistry, 35 Ballygunge Circular Road, Calcutta 700-019 (India)

    1993-07-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation.

  16. Lipid peroxidation and antioxidant enzymes in male infertility.

    Directory of Open Access Journals (Sweden)

    Dandekar S

    2002-07-01

    Full Text Available BACKGROUND AND AIM: Mammalian spermatozoa are rich in polyunsaturated fatty acids and are very susceptible to attack by reactive oxygen species (ROS and membrane lipid peroxide ion. Normally a balance is maintained between the amount of ROS produced and that scavenged. Cellular damage arises when this equilibrium is disturbed. A shift in the levels of ROS towards pro-oxidants in semen and vaginal secretions can induce an oxidative stress on spermatozoa. The aim was to study lipid peroxidation and antioxidant enzymes such as catalase, glutathione peroxidase and superoxide dismutase (SOD and to correlate the same, with the ′water test′, in male infertility. SETTINGS: Experimental study. SUBJECTS AND METHODS: Ejaculates from a total of 83 infertile and fertile healthy individuals were obtained. Lipid peroxidation and antioxidant enzyme levels were studied and correlated with water test. RESULTS: The results indicate that (i the antioxidant enzyme catalase showed no significant changes in the various pathological samples, (ii antioxidant enzymes SOD and glutathione peroxidase correlate positively with asthenozoospermic samples and (iii the degree of lipid peroxidation also correlates positively with the poorly swollen sperm tails. The increase in SOD and glutathione peroxidase values, in the pathological cases represents an attempt made to overcome the reactive oxygen species. CONCLUSION: Water test could be used as a preliminary marker test for sperm tail damage by reactive oxygen species, since it correlates very well with lipid peroxidation and antioxidant enzymes.

  17. The Amoebicidal Effect of Ergosterol Peroxide Isolated from Pleurotus ostreatus.

    Science.gov (United States)

    Meza-Menchaca, Thuluz; Suárez-Medellín, Jorge; Del Ángel-Piña, Christian; Trigos, Ángel

    2015-12-01

    Dysentery is an inflammation of the intestine caused by the protozoan parasite Entamoeba histolytica and is a recurrent health problem affecting millions of people worldwide. Because of the magnitude of this disease, finding novel strategies for treatment that does not affect human cells is necessary. Ergosterol peroxide is a sterol particularly known as a major cytotoxic agent with a wide spectrum of biological activities produced by edible and medicinal mushrooms. The aim of this report is to evaluate the amoebicidal activity of ergosterol peroxide (5α, 8α-epidioxy-22E-ergosta-6,22-dien-3β-ol isolated from 5α, 8α-epidioxy-22E-ergosta-6,22-dien-3β-ol) (Jacq.) P. Kumm. f. sp. Florida. Our results show that ergosterol peroxide produced a strong cytotoxic effect against amoebic growth. The inhibitory concentration IC50 of ergosterol peroxide was evaluated. The interaction between E. histolytica and ergosterol peroxide in vitro resulted in strong amoebicidal activity (IC50  = 4.23 nM) that may be due to the oxidatory effect on the parasitic membrane. We also tested selective toxicity of ergosterol peroxide using a cell line CCL-241, a human epithelial cell line isolated from normal human fetal intestinal tissue. To the best of our knowledge, this is the first report on the cytotoxicity of ergosterol peroxide against E. histolytica, which uncovers a new biological property of the lipidic compound isolated from Pleurotus ostreatus (Jacq.) P. Kumm. f. sp. Florida. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Comparative studies on sulfur, peroxide, and radiation vulcanization of EFDM rubber

    International Nuclear Information System (INIS)

    Abdel-Aziz, M.M.; Basfar, A.A.; Mofti, S.

    2000-01-01

    The temperature and concentration dependence of the vulcanization characteristics and mechanical properties of epdm rubber containing various concentrations of peroxide compounds was studied. The peroxides used are Luperox Di, Luperox 500-40 Ke, peroximon Dc Sc and peroximon Dc 40 Ke. The optimum cure parameters for the different types of peroxides indicated that Luperox Di, relatively, Give the best properties among the studied peroxides. The mechanical properties of EPDM containing different concentrations of Luperox Di and vulcanized at different temperatures were compared with those of either radiation or sulfur-cured EPDM. The modulus stress and tensile strength of the Luperox Di-cured EPDM were found to increase with either increasing the temperature of vulcanization and/ or concentration of the peroxide. Moreover, the tensile strength values are much higher than those of the sulfur-cured samples, except for those with low concentration of peroxide and vulcanized at relatively low temperature. A comparable result to those of the chemically vulcanized samples was attained by the radiation- vulcanized samples containing 1 phr of crosslinking agent and irradiated to 150 KGy

  19. Oxidation resistant peroxide cross-linked UHMWPE produced by blending and surface diffusion

    International Nuclear Information System (INIS)

    Gul, Rizwan M; Oral, Ebru; Muratoglu, Orhun K

    2014-01-01

    Ultra-high molecular weight polyethylene (UHMWPE) has been widely used as acetabular cup in total hip replacement (THR) and tibial component in total knee replacement (TKR). Crosslinking of UHMWPE has been successful used to improve its wear performance leading to longer life of orthopedic implants. Crosslinking can be performed by radiation or organic peroxides. Peroxide crosslinking is a convenient process as it does not require specialized equipment and the level of crosslinking can be manipulated by changing the amount of peroxide added. However, there is concern about the long-term stability of these materials due to possible presence of by-products. Vitamin E has been successfully used to promote long-term oxidative stability of UHMWPE. In this study, UHMWPE has been crosslinked using organic peroxide in the presence of Vitamin E to produce an oxidation resistant peroxide crosslinked material. Crosslinking was performed both in bulk by mixing peroxide and resin, and only on the surface using diffusion of peroxides.The results show that UHMWPE can be crosslinked using organic peroxides in the presence of vitamin E by both methods. However, the level of crosslinking decreases with the increase in vitamin E content. The wear resistance increases with the increase in crosslink density, and oxidation resistance significantly increases due to the presence of vitamin E

  20. Oxidation resistant peroxide cross-linked UHMWPE produced by blending and surface diffusion

    International Nuclear Information System (INIS)

    Gul, R. M.; Oral, E.; Muratoglu, O. K.

    2013-01-01

    Ultra-high molecular weight polyethylene (UHMWPE) has been widely used as acetabular cup in total hip replacement (THR) and tibial component in total knee replacement (TKR). Crosslinking of UHMWPE has been successful used to improve its wear performance leading to longer life of orthopedic implants. Crosslinking can be performed by radiation or organic peroxides. Peroxide crosslinking is a convenient process as it does not require specialized equipment and the level of crosslinking can be manipulated by changing the amount of peroxide added. However, there is concern about the long-term stability of these materials due to possible presence of by-products. Vitamin E has been successfully used to promote long-term oxidative stability of UHMWPE. In this study, UHMWPE has been crosslinked using organic peroxide in the presence of Vitamin E to produce an oxidation resistant peroxide crosslinked material. Crosslinking was performed both in bulk by mixing peroxide and resin, and only on the surface using diffusion of peroxides.The results show that UHMWPE can be crosslinked using organic peroxides in the presence of vitamin E by both methods. However, the level of crosslinking decreases with the increase in vitamin E content. The wear resistance increases with the increase in crosslink density, and oxidation resistance significantly increases due to the presence of vitamin E. (author)

  1. Safety issues of tooth whitening using peroxide-based materials.

    Science.gov (United States)

    Li, Y; Greenwall, L

    2013-07-01

    In-office tooth whitening using hydrogen peroxide (H₂O₂) has been practised in dentistry without significant safety concerns for more than a century. While few disputes exist regarding the efficacy of peroxide-based at-home whitening since its first introduction in 1989, its safety has been the cause of controversy and concern. This article reviews and discusses safety issues of tooth whitening using peroxide-based materials, including biological properties and toxicology of H₂O₂, use of chlorine dioxide, safety studies on tooth whitening, and clinical considerations of its use. Data accumulated during the last two decades demonstrate that, when used properly, peroxide-based tooth whitening is safe and effective. The most commonly seen side effects are tooth sensitivity and gingival irritation, which are usually mild to moderate and transient. So far there is no evidence of significant health risks associated with tooth whitening; however, potential adverse effects can occur with inappropriate application, abuse, or the use of inappropriate whitening products. With the knowledge on peroxide-based whitening materials and the recognition of potential adverse effects associated with the procedure, dental professionals are able to formulate an effective and safe tooth whitening regimen for individual patients to achieve maximal benefits while minimising potential risks.

  2. Thermochemistry of cyclic acetone peroxides

    Energy Technology Data Exchange (ETDEWEB)

    Sinditskii, V.P., E-mail: vps@rctu.ru [Mendeleev University of Chemical Technology, 9 Miusskaya Square, 125047 Moscow (Russian Federation); Kolesov, V.I.; Egorshev, V.Yu.; Patrikeev, D.I. [Mendeleev University of Chemical Technology, 9 Miusskaya Square, 125047 Moscow (Russian Federation); Dorofeeva, O.V. [Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)

    2014-06-01

    Highlights: • Old data on DADP and TATP enthalpies of formation have been revised. • Combining Gaussian-4 (G4) theory with an isodesmic reaction scheme allowed calculated enthalpies of formation of TATP and DADP. • Oxygen bomb calorimetry measurements allowed experimental enthalpies of formation of the peroxides. • Both experimental and calculated values show a satisfactory agreement between each other. • The newly obtained enthalpies reasonably account for the observed derivative parameters: heats of decomposition, combustion, and explosion. - Abstract: Two potentially initiating explosive peroxides, diacetonediperoxide (DADP) and triacetonetriperoxide (TATP), were studied in respect to their thermochemical properties. To get the internally self-consistent estimations of gas-phase enthalpy of formation of DADP and TATP, their values were calculated by combining Gaussian-4 (G4) theory with an isodesmic reaction scheme. The energies of combustion (Δ{sub c}U) were measured and the standard enthalpies of formation (Δ{sub f}H{sub 298}{sup °}) of DADP and TATP were derived using the standard enthalpies of formation of the combustion products. The heat of explosion was measured for small low-pressed charges of the peroxides. The obtained enthalpies of formation of DADP and TATP were found to agree well with quantum chemical calculations and reasonably account for the observed derivative parameters: heats of decomposition, combustion, and detonation.

  3. A sacrificial millipede altruistically protects its swarm using a drone blood enzyme, mandelonitrile oxidase.

    Science.gov (United States)

    Ishida, Yuko; Kuwahara, Yasumasa; Dadashipour, Mohammad; Ina, Atsutoshi; Yamaguchi, Takuya; Morita, Masashi; Ichiki, Yayoi; Asano, Yasuhisa

    2016-06-06

    Soldiers of some eusocial insects exhibit an altruistic self-destructive defense behavior in emergency situations when attacked by large enemies. The swarm-forming invasive millipede, Chamberlinius hualienensis, which is not classified as eusocial animal, exudes irritant chemicals such as benzoyl cyanide as a defensive secretion. Although it has been thought that this defensive chemical was converted from mandelonitrile, identification of the biocatalyst has remained unidentified for 40 years. Here, we identify the novel blood enzyme, mandelonitrile oxidase (ChuaMOX), which stoichiometrically catalyzes oxygen consumption and synthesis of benzoyl cyanide and hydrogen peroxide from mandelonitrile. Interestingly the enzymatic activity is suppressed at a blood pH of 7, and the enzyme is segregated by membranes of defensive sacs from mandelonitrile which has a pH of 4.6, the optimum pH for ChuaMOX activity. In addition, strong body muscle contractions are necessary for de novo synthesis of benzoyl cyanide. We propose that, to protect its swarm, the sacrificial millipede also applies a self-destructive defense strategy-the endogenous rupturing of the defensive sacs to mix ChuaMOX and mandelonitrile at an optimum pH. Further study of defensive systems in primitive arthropods will pave the way to elucidate the evolution of altruistic defenses in the animal kingdom.

  4. Creating Drug Solubilization Compartments via Phase Separation in Multicomponent Buccal Patches Prepared by Direct Hot Melt Extrusion-Injection Molding.

    Science.gov (United States)

    Alhijjaj, Muqdad; Bouman, Jacob; Wellner, Nikolaus; Belton, Peter; Qi, Sheng

    2015-12-07

    Creating in situ phase separation in solid dispersion based formulations to allow enhanced functionality of the dosage form, such as improving dissolution of poorly soluble model drug as well as being mucoadhesive, can significantly maximize the in vitro and in vivo performance of the dosage form. This formulation strategy can benefit a wide range of solid dosage forms for oral and alternative routes of delivery. This study using buccal patches as an example created separated phases in situ of the buccal patches by selecting the excipients with different miscibility with each other and the model drug. The quaternary dispersion based buccal patches containing PEG, PEO, Tween 80, and felodipine were prepared by direct hot melt extrusion-injection molding (HME-IM). The partial miscibility between Tween 80 and semicrystalline PEG-PEO led to the phase separation after extrusion. The Tween phases acted as drug solubilization compartments, and the PEG-PEO phase had the primary function of providing mucoadhesion and carrier controlled dissolution. As felodipine was preferably solubilized in the amorphous regions of PEG-PEO, the high crystallinity of PEG-PEO resulted in an overall low drug solubilizing capacity. Tween 80 was added to improve the solubilization capacity of the system as the model drug showed good solubility in Tween. Increasing the drug loading led to the supersaturation of drug in Tween compartments and crystalline drug dispersed in PEG-PEO phases. The spatial distribution of these phase-separated compartments was mapped using X-ray micro-CT, which revealed that the domain size and heterogeneity of the phase separation increased with increasing the drug loading. The outcome of this study provides new insights into the applicability of in situ formed phase separation as a formulation strategy for the delivery of poorly soluble drugs and demonstrated the basic principle of excipient selection for such technology.

  5. A biosensor for hydrogen peroxide detection based on electronic properties of carbon nanotubes

    Science.gov (United States)

    Majidi, Roya

    2013-01-01

    Density functional theory has been used to study the effect of hydrogen peroxide on the electronic properties of single walled carbon nanotubes. The metallic and semiconducting carbon nanotubes have been considered in the presence of different number of hydrogen peroxide. The results indicate that hydrogen peroxide has no significant effect on the metallic nanotube and these nanotubes remain to be metallic. In contrast, the electronic properties of the semiconducting nanotubes are so sensitive to hydrogen peroxide. The energy band gap of these nanotubes is decreased by increasing the number of hydrogen peroxide. The electronic sensivity of the carbon nanotubes to hydrogen peroxide opens new insights into developing biosensors based on the single walled carbon nanotubes.

  6. Destruction of oxalate by reaction with hydrogen peroxide. [Hydrazine oxalate

    Energy Technology Data Exchange (ETDEWEB)

    Mailen, J.C.; Tallent, O.K.; Arwood, P.C.

    1981-09-01

    The destruction of oxalate by oxidation to carbon dioxide using hydrogen peroxide was studied as an alternative method for the disposal of oxalate in connection with the possible use of an aqueous hydrazine oxalate solution as a scrubbing agent for solvent cleanup in processes for the recovery of uranium, plutonium, and thorium by solvent extraction. The rate of oxidation of oxalate by hydrogen peroxide in acid solution at the reflux temperature was adequate for process application; reaction half-times at 100/sup 0/C were less than one hour when the hydrogen peroxide concentration was greater than 0.5 M. The reaction was first order with respect to both the oxalate and hydrogen peroxide concentrations and had an activation energy of 58.7 kJ/g-mol. The rate increased with the hydrogen ion concentration as (H/sup +/)/sup 0/ /sup 3/ but was not significantly affected by the presence of 100 ppM of uranium or copper in solution. In the near-neutral hydrazine oxalate solutions, the reaction of either component with hydrogen peroxide was too slow for process application.

  7. Mechanisms of wet oxidation by hydrogen peroxide

    International Nuclear Information System (INIS)

    Baxter, R.A.

    1987-08-01

    A research programme is currently under way at BNL and MEL to investigate the possible use of Hydrogen Peroxide with metal ion catalysts as a wet oxidation treatment system for CEGB organic radioactive wastes. The published literature relating to the kinetics and mechanism of oxidation and decomposition reactions of hydrogen peroxide is reviewed and the links with practical waste management by wet oxidation are examined. Alternative wet oxidation systems are described and the similarities to the CEGB research effort are noted. (author)

  8. Determination of the Tautomeric Equilibria of Pyridoyl Benzoyl -Diketones in the Liquid and Solid State through the use of Deuterium Isotope Effects on 1H and 13C NMR Chemical Shifts and Spin Coupling Constants

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Borisov, Eugeny V.; Lindon, John C.

    2015-01-01

    The tautomeric equilibria for 2-pyridoyl-, 3-pyridoyl-, and 4-pyridoyl-benzoyl methane have been investigated using deuterium isotope effects on 1H and 13C chemical shifts both in the liquid and the solid state. Equilibria are established both in the liquid and the solid state. In addition......, in the solution state the 2-bond and 3-bond J(1H–13C) coupling constants have been used to confirm the equilibrium positions. The isotope effects due to deuteriation at the OH position are shown to be superior to chemical shift in determination of equilibrium positions of these almost symmetrical -pyridoyl......-benzoyl methanes. The assignments of the NMR spectra are supported by calculations of the chemical shifts at the DFT level. The equilibrium positions are shown to be different in the liquid and the solid state. In the liquid state the 4-pyridoyl derivative is at the B-form (C-1 is OH), whereas the 2-and 3-pyridoyl...

  9. Artificial Citrate Operon Confers Mineral Phosphate Solubilization Ability to Diverse Fluorescent Pseudomonads

    Science.gov (United States)

    Adhikary, Hemanta; Sanghavi, Paulomi B.; Macwan, Silviya R.; Archana, Gattupalli; Naresh Kumar, G.

    2014-01-01

    Citric acid is a strong acid with good cation chelating ability and can be very efficient in solubilizing mineral phosphates. Only a few phosphate solubilizing bacteria and fungi are known to secrete citric acids. In this work, we incorporated artificial citrate operon containing NADH insensitive citrate synthase (gltA1) and citrate transporter (citC) genes into the genome of six-plant growth promoting P. fluorescens strains viz., PfO-1, Pf5, CHAO1, P109, ATCC13525 and Fp315 using MiniTn7 transposon gene delivery system. Comprehensive biochemical characterization of the genomic integrants and their comparison with plasmid transformants of the same operon in M9 minimal medium reveals the highest amount of ∼7.6±0.41 mM citric and 29.95±2.8 mM gluconic acid secretion along with ∼43.2±3.24 mM intracellular citrate without affecting the growth of these P. fluorescens strains. All genomic integrants showed enhanced citric and gluconic acid secretion on Tris-Cl rock phosphate (TRP) buffered medium, which was sufficient to release 200–1000 µM Pi in TRP medium. This study demonstrates that MPS ability could be achieved in natural fluorescent pseudomonads by incorporation of artificial citrate operon not only as plasmid but also by genomic integration. PMID:25259527

  10. Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources

    Science.gov (United States)

    Mba, Caroline C.

    1994-03-01

    Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.

  11. Different modes of hydrogen peroxide action during seed germination

    Directory of Open Access Journals (Sweden)

    Łukasz eWojtyla

    2016-02-01

    Full Text Available Hydrogen peroxide was initially recognized as a toxic molecule that causes damage at different levels of cell organization and thus losses in cell viability. From the 1990s, the role of hydrogen peroxide as a signaling molecule in plants has also been discussed. The beneficial role of H2O2 as a central hub integrating signaling network in response to biotic and abiotic stress and during developmental processes is now well established. Seed germination is the most pivotal phase of the plant life cycle, affecting plant growth and productivity. The function of hydrogen peroxide in seed germination and seed aging has been illustrated in numerous studies; however, the exact role of this molecule remains unknown. This review evaluates evidence that shows that H2O2 functions as a signaling molecule in seed physiology in accordance with the known biology and biochemistry of H2O2. The importance of crosstalk between hydrogen peroxide and a number of signaling molecules, including plant phytohormones such as abscisic acid, gibberellins and ethylene and reactive molecules such as nitric oxide and hydrogen sulfide acting on cell communication and signaling during seed germination, is highlighted. The current study also focuses on the detrimental effects of H2O2 on seed biology, i.e., seed aging that leads to a loss of germination efficiency. The dual nature of hydrogen peroxide as a toxic molecule on one hand and as a signal molecule on the other is made possible through the precise spatial and temporal control of its production and degradation. Levels of hydrogen peroxide in germinating seeds and young seedlings can be modulated via pre-sowing seed priming/conditioning. This rather simple method is shown to be a valuable tool for improving seed quality and for enhancing seed stress tolerance during post-priming germination. In this review, we outline how seed priming/conditioning affects the integrative role of hydrogen peroxide in seed germination and

  12. Diesel autothermal reforming with hydrogen peroxide for low-oxygen environments

    International Nuclear Information System (INIS)

    Han, Gwangwoo; Lee, Sangho; Bae, Joongmyeon

    2015-01-01

    Highlights: • The concept of diesel reforming using hydrogen peroxide was newly proposed. • Characteristics of hydrogen peroxide was experimentally investigated. • Thermodynamically possible operating conditions were analyzed. • Catalytic performance of Ni–Ru/CGO for various diesel compounds was evaluated. • Long-term testing was successfully conducted using Korean commercial diesel. - Abstract: To operate fuel cells effectively in low-oxygen environments, such as in submarines and unmanned underwater vehicles, a hydrogen source with high hydrogen storage density is required. In this paper, diesel autothermal reforming (ATR) with hydrogen peroxide as an alternative oxidant is proposed as a hydrogen production method. Diesel fuel has higher hydrogen density than metal hydrides or other hydrocarbons. In addition, hydrogen peroxide can decompose into steam and oxygen, which are required for diesel ATR. Moreover, both diesel fuel and hydrogen peroxide are liquid states, enabling easy storage for submarine applications. Hydrogen peroxide exhibited the same characteristics as steam and oxygen when used as an oxidant in diesel reforming when pre-decomposition method was used. The thermodynamically calculated operating conditions were a steam-to-carbon ratio (SCR) of 3.0, an oxygen-to-carbon ratio (OCR) of 0.5, and temperatures below 700 °C to account for safety issues associated with hydrogen peroxide use and exothermic reactions. Catalytic activity and stability tests over Ni–Ru (19.5–0.5 wt.%)/Ce 0.9 Gd 0.1 O 2−x were conducted using various diesel compounds. Furthermore, long-term diesel ATR tests were conducted for 200 h using Korean commercial diesel. The degradation rate was 3.67%/100 h without the production of ethylene

  13. Solubilization, partial purification, and reconstitution of glutamate- and N-methyl-D-aspartate-activated cation channels from brain synaptic membranes

    International Nuclear Information System (INIS)

    Ly, A.M.; Michaelis, E.K.

    1991-01-01

    L-Glutamate-activated cation channel proteins from rat brain synaptic membranes were solubilized, partially purified, and reconstituted into liposomes. Optimal conditions for solubilization and reconstitution included treatment of the membranes with nonionic detergents in the presence of neutral phospholipids plus glycerol. Quench-flow procedures were developed to characterize the rapid kinetics of ion flux induced by receptor agonists. [ 14 C]Methylamine, a cation that permeates through the open channel of both vertebrate and invertebrate glutamate receptors, was used to measure the activity of glutamate receptor-ion channel complexes in reconstituted liposomes. L-Glutamate caused an increase in the rate of [ 14 C]methylamine influx into liposomes reconstituted with either solubilized membrane proteins or partially purified glutamate-binding proteins. Of the major glutamate receptor agonists, only N-methyl-D-aspartate activated cation fluxes in liposomes reconstituted with glutamate-binding proteins. In liposomes reconstituted with glutamate-binding proteins, N-methyl-D-aspartate- or glutamate-induced influx of NA + led to a transient increase in the influx of the lipid-permeable anion probe S 14 CN - . These results indicate the functional reconstitution of N-methyl-D-aspartate-sensitive glutamate receptors and the role of the ∼69-kDa protein in the function of these ion channels

  14. A Study on Solubilization of Poorly Soluble Drugs by Cyclodextrins and Micelles: Complexation and Binding Characteristics of Sulfamethoxazole and Trimethoprim

    Directory of Open Access Journals (Sweden)

    Sinem Göktürk

    2012-01-01

    > α-CD. With taking into consideration of solubilization capacity of SDS micelles, it has been found that the solubility enhancement of TMP is much higher than that of SMX in the presence of SDS micelles. The binding constants of SMX and TMP obtained from the Benesi-Hildebrand equation are also confirmed by the estimated surface properties of SDS, employing the surface tension measurements. In order to elucidate the solubilization characteristics the surface tension measurements were also performed for nonionic surfactant Triton X-100. Polarity of the microenvironment and probable location of SMX and TMP were also discussed in the presence of various organic solvents.

  15. Hydrogen peroxide oxidant fuel cell systems for ultra-portable applications

    Science.gov (United States)

    Valdez, T. I.; Narayanan, S. R.

    2001-01-01

    This paper will address the issues of using hydrogen peroxide as an oxidant fuel in a miniature DMFC system. Cell performance for DMFC based fuel cells operating on hydrogen peroxide will be presented and discussed.

  16. Reproducing Phenomenology of Peroxidation Kinetics via Model Optimization

    Science.gov (United States)

    Ruslanov, Anatole D.; Bashylau, Anton V.

    2010-06-01

    We studied mathematical modeling of lipid peroxidation using a biochemical model system of iron (II)-ascorbate-dependent lipid peroxidation of rat hepatocyte mitochondrial fractions. We found that antioxidants extracted from plants demonstrate a high intensity of peroxidation inhibition. We simplified the system of differential equations that describes the kinetics of the mathematical model to a first order equation, which can be solved analytically. Moreover, we endeavor to algorithmically and heuristically recreate the processes and construct an environment that closely resembles the corresponding natural system. Our results demonstrate that it is possible to theoretically predict both the kinetics of oxidation and the intensity of inhibition without resorting to analytical and biochemical research, which is important for cost-effective discovery and development of medical agents with antioxidant action from the medicinal plants.

  17. Interaction Effects of Phosphate Solubilizing Bacteria and Mycorrhiza on the Growth and Phosphorus uptakeof Sorghum

    Directory of Open Access Journals (Sweden)

    Abdolhossein ziaeyan

    2017-01-01

    Full Text Available Introduction: The most abundant of agricultural soils in Iran, are calcareous. In calcareous soils, phosphorus fertilizers use efficiency is low. The usage of soil microorganisms is one of the effective ways to increment the uptake of phosphorus in calcareous soils. This microorganisms using various mechanisms, including the production of plant hormones or the production of organic and inorganic acids to dissolve the insoluble phosphorous compounds. Mycorrhizal symbiosis is also one of the most recognized and important symbiosis relationship found in the world. In a mycorrhizal symbiosis,plants can be able to absorb more nutrients and water from soil and fungus plays a protective role as a growth enhancer and make the plants more tolerable to biotic (pathogens and abiotic (drought, cold and salinity stresses .This research conducted to study phosphate solubilizing bacteria and mycorrhiza roles on sorghum growth and phosphorus availability to this plant. Materials and methods: To achieve the desired goals, a pot experiment was conducted as a factorial in completely randomized design with sixteen treatments in three replications. The treatments were combination of four P levels of zero, 25, 50, and 75 mg kg-1 P2O5 from triple super phosphate source, the two treatments of inoculation and without inoculation of phosphate solubilizing bacteria and the two treatments of inoculation and no inoculation of mycorrizal fungus. Required fertilizers based on initial soil test results were supplied. Accordingly, the same amount of nitrogen, 80 mg kg-1 (30 mg kg-1 before planting and 50 mg kg-1 after planting twice as urea source, 10 mg Zn kg-1 and 5 mg kg-1 Cu per kg soil as the forms of Zinc sulphate (ZnSO4.7H2O and copper sulphate (CuSO4.H2O were added to each soil sample. Required Phosphorus also was calculated based on treatments and added to potting soil. Each pot size was 5 kg. every sample was thoroughly mixed and then were placed in pots. At the same

  18. Potassium solubilizing bacteria-assisted phytoextraction of radiocesium on pechay plants grown in cesium contaminated Fukushima Soils

    International Nuclear Information System (INIS)

    Rallos, R.V.; Yokoyama, T.

    2015-01-01

    Increasing the efficiency of metal uptake by plants is important to achieve successful phytoremediation of metal-polluted soils. The presence of potassium solubilizing bacteria (KSB) increases the solubilization of K-containing minerals thereby enhancing the availability of potassium (K+) and other cations including radicesium (137Cs+) for plant uptake. In this study, five KSB isolates were obtained from soybean rhizosphere in Fukushima radiocesium contaminated soils. Based on biochemical and 16S rRNA gene sequence analysis, the bacteria were identified as Bacillus megaterium, Pseudomonas putida, P. frederiksbergensis, Burkholderia sabiae, and P. mandelii. The KSB isolates were evaluated for plant growth promotion, potassium (K) uptake and radiocesium phytoextraction of pechay in three different cesium-contaminated Fukushima soils. Inoculation with KSB showed beneficial effects on plant growth and increased the phytoextraction of radiocesium, with much greater magnitude in roots than in shoots. The results indicated that KSB inoculation may be essential in managing radiocesium-contaminated soils and manipulating the transfer from soils to plants.(author)

  19. Catalyst-free activation of peroxides under visible LED light irradiation through photoexcitation pathway

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yaowen [Department of Environmental Engineering, Wuhan University, Wuhan, 430079 (China); Shenzhen Research Institute of Wuhan University, Shenzhen, 518057 (China); Li, Yixi; Yao, Linyu; Li, Simiao; Liu, Jin [Department of Environmental Engineering, Wuhan University, Wuhan, 430079 (China); Zhang, Hui, E-mail: eeng@whu.edu.cn [Department of Environmental Engineering, Wuhan University, Wuhan, 430079 (China); Shenzhen Research Institute of Wuhan University, Shenzhen, 518057 (China)

    2017-05-05

    Highlights: • Persulfate could decolorize Rhodamine B (RhB) directly via non-radical reactions. • LED lamps emitting white light were utilized as the visible light source. • Dyes could activate peroxides through photoexcitation pathway. • Decolorization of dyes and production of radicals were achieved simultaneously. • The catalyst-free peroxide/dye/Vis process was effective in a broad pH range. - Abstract: Catalysts are known to activate peroxides to generate active radicals (i.e., hydroxyl radical (·OH) and sulfate radical (SO{sub 4}·{sup −})) under certain conditions, but the activation of peroxides in the absence of catalysts under visible light irradiation has been rarely reported. This work demonstrates a catalyst-free activation of peroxides for the generation of ·OH and/or SO{sub 4}·{sup −} through photoexcited electron transfer from organic dyes to peroxides under visible LED light irradiation, where Rhodamine B (RhB) and Eosin Y (EY) were selected as model dyes. The formation of ·OH and/or SO{sub 4}·{sup −} in the reactions and the electron transfer from the excited dyes to peroxides were validated via electron paramagnetic resonance (EPR), photoluminescence (PL) spectra and cyclic voltammetry (CV). The performance of the peroxide/dye/Vis process was demonstrated to be altered depending on the target substrate. Meanwhile, the peroxide/dye/Vis process was effective for simultaneous decolorization of dyes and production of active radicals under neutral even or basic conditions. The findings of this study clarified a novel photoexcitation pathway for catalyst-free activation of peroxides under visible light irradiation, which could avoid the secondary metal ion (dissolved or leached) pollution from the metal-based catalysts and expand the application range of the peroxide-based catalytic process.

  20. Possible role of organic peroxides in the detection of irradiated food

    International Nuclear Information System (INIS)

    Qi Shengchu; Wu Jilan

    1993-01-01

    In order to determine the level of organic peroxides induced by autooxidation, random sampling of pork has been performed. The organic peroxide content in unirradiated pork has been estimated as (5.4 ± 3.0) x10 -5 mol.kg -1 . The dependence of yield of peroxide in pork, minced meat and braised chicken on absorbed dose has been investigated. For killing trichinae 0.5 ∼ 1 kGy is used, the quantity of peroxide in pork will be 4x10 -4 mol.kg -1 for 1 kGy, which is 3.7 ∼ 7.4 times greater than the background. If 3 kGy is used to eliminate Salmonella, the quantity of peroxides in pork will be 1.3 x10 -3 mol.kg -1 , which approaches 24 times greater than the average value of background. When minced meat was irradiated in the presence of air, a chain reaction took place with G value 30.2. Radiation processing dose of braised chicken for shelf-life extension is ∼ 9kGy, organic peroxide content in braised chicken fat is 32.5 x10 -4 mol.kg -1 , which is about 14.7 times greater than average value (2.2x10 -4 mol.kg -1 ) in unirradiated one. Applying the peroxide method to qualitatively detect irradiated food containing fat is satisfactory, if combined with measuring the ESR signal of irradiated bone which will improve the detection method. (author)

  1. Maltose-neopentyl glycol (MNG) amphiphiles for solubilization, stabilization and crystallization of membrane proteins

    OpenAIRE

    Chae, Pil Seok; Rasmussen, Søren G. F.; Rana, Rohini; Gotfryd, Kamil; Chandra, Richa; Goren, Michael A.; Kruse, Andrew C.; Nurva, Shailika; Loland, Claus J.; Pierre, Yves; Drew, David; Popot, Jean-Luc; Picot, Daniel; Fox, Brian G.; Guan, Lan

    2010-01-01

    The understanding of integral membrane protein (IMP) structure and function is hampered by the difficulty of handling these proteins. Aqueous solubilization, necessary for many types of biophysical analysis, generally requires a detergent to shield the large lipophilic surfaces displayed by native IMPs. Many proteins remain difficult to study owing to a lack of suitable detergents. We introduce a class of amphiphiles, each of which is built around a central quaternary carbon atom derived from...

  2. Synthesis of Covalently Cross-Linked Colloidosomes from Peroxidized Pickering Emulsions

    Directory of Open Access Journals (Sweden)

    Nadiya Popadyuk

    2016-10-01

    Full Text Available A new approach to the formation of cross-linked colloidosomes was developed on the basis of Pickering emulsions that were stabilized exclusively by peroxidized colloidal particles. Free radical polymerization and a soft template technique were used to convert droplets of a Pickering emulsion into colloidosomes. The peroxidized latex particles were synthesized in the emulsion polymerization process using amphiphilic polyperoxide copolymers poly(2-tert-butylperoxy-2-methyl-5-hexen-3-ine-co-maleic acid (PM-1-MAc or poly[N-(tert-butylperoxymethylacrylamide]-co-maleic acid (PM-2-MAc, which were applied as both initiators and surfactants (inisurfs. The polymerization in the presence of the inisurfs results in latexes with a controllable amount of peroxide and carboxyl groups at the particle surface. Peroxidized polystyrene latex particles with a covalently grafted layer of inisurf PM-1-MAc or PM-2-MAc were used as Pickering stabilizers to form Pickering emulsions. A mixture of styrene and/or butyl acrylate with divinylbenzene and hexadecane was applied as a template for the synthesis of colloidosomes. Peroxidized latex particles located at the interface are involved in the radical reactions of colloidosomes formation. As a result, covalently cross-linked colloidosomes were obtained. It was demonstrated that the structure of the synthesized (using peroxidized latex particles colloidosomes depends on the amount of functional groups and pH during the synthesis. Therefore, the size and morphology of colloidosomes can be controlled by latex particle surface properties.

  3. Probing skin interaction with hydrogen peroxide using diffuse reflectance spectroscopy

    International Nuclear Information System (INIS)

    Zonios, George; Dimou, Aikaterini; Galaris, Dimitrios

    2008-01-01

    Hydrogen peroxide is an important oxidizing agent in biological systems. In dermatology, it is frequently used as topical antiseptic, it has a haemostatic function, it can cause skin blanching, and it can facilitate skin tanning. In this work, we investigated skin interaction with hydrogen peroxide, non-invasively, using diffuse reflectance spectroscopy. We observed transient changes in the oxyhaemoglobin and deoxyhaemoglobin concentrations as a result of topical application of dilute H 2 O 2 solutions to the skin, with changes in deoxyhaemoglobin concentration being more pronounced. Furthermore, we did not observe any appreciable changes in melanin absorption properties as well as in the skin scattering properties. We also found no evidence for production of oxidized haemoglobin forms. Our observations are consistent with an at least partial decomposition of hydrogen peroxide within the stratum corneum and epidermis, with the resulting oxygen and/or remaining hydrogen peroxide inducing vasoconstriction to dermal blood vessels and increasing haemoglobin oxygen saturation. An assessment of the effects of topical application of hydrogen peroxide to the skin may serve as the basis for the development of non-invasive techniques to measure skin antioxidant capacity and also may shed light onto skin related disorders such as vitiligo

  4. Selection of phosphorus solubilizing bacteria with biocontrol potential for growth in phosphorus rich animal bone charcoal

    NARCIS (Netherlands)

    Postma, J.; Nijhuis, E.H.; Sommeus, E.

    2010-01-01

    Bacteria with the ability to solubilize phosphorus (P) and to improve plant health were selected and tested for growth and survival in P-rich animal bone charcoal (ABC). ABC is suggested to be suitable as a carrier for biocontrol agents, offering them a protected niche as well as delivering

  5. The effect of hydrogen peroxide and ultraviolet irradiation on non-sporing bacteria

    International Nuclear Information System (INIS)

    Bayliss, C.E.; Waites, W.M.

    1980-01-01

    A kill of 99.99% was obtained in cell suspensions of Escherichia coli and Streptococcus faecalis by incubation with hydrogen peroxide 1.0%(w/v) for 75 and 180 min respectively. The same kill was produced by 30s irradiation with ultraviolet (u.v.) light in the presence of hydrogen peroxide 1.0% (w/v). This simultaneous treatment with u.v. and hydrogen peroxide produced a synergistic kill at least 30-fold greater than that produced by irradiation of cell suspensions of Esch. coli with or without subsequent incubation with hydrogen peroxide. (author)

  6. Nanolipoprotein particles and related methods and systems for protein capture, solubilization, and/or purification

    Energy Technology Data Exchange (ETDEWEB)

    Chromy, Brett A.; Henderson, Paul; Hoeprich, Jr, Paul D.

    2016-10-04

    Provided herein are methods and systems for assembling, solubilizing and/or purifying a membrane associated protein in a nanolipoprotein particle, which comprise a temperature transition cycle performed in presence of a detergent, wherein during the temperature transition cycle the nanolipoprotein components are brought to a temperature above and below the gel to liquid crystalling transition temperature of the membrane forming lipid of the nanolipoprotein particle.

  7. Sludge disintegration techniques - assessment of their impacts on solubilization of organic carbon and methane production

    OpenAIRE

    Fatoorehchi, Elham

    2016-01-01

    In the present thesis, ozone, sodium hydroxide and ultrasound were conducted to disintegrate the excess sludge prior to anaerobic digestion with the aim of improving methane production. The impacts of different sludge disintegration methods on the molecular size distribution of DOC solubilized after disintegration were investigated using size exclusion chromatography with online organic carbon detection (SEC-OCD).

  8. Comparison of Yeast Cell Protein Solubilization Procedures for Two-dimensional Electrophoresis

    DEFF Research Database (Denmark)

    Harder, A; Wildgruber, R; Nawrocki, A

    1999-01-01

    Three different procedures for the solubilization of yeast (S. cerevisiae) cell proteins were compared on the basis of the obtained two-dimensional (2-D) polypeptide patterns. Major emphasis was laid on minimizing handling steps, protein modification or degradation, and quantitative loss of high...... with sodium dodecyl sulfate (SDS) buffer, consisting of 1% SDS and 100 mM tris(hydroxymethyl)aminomethane (Tris)-HCl, pH 7.0, followed by dilution with "standard" lysis buffer, and (iii) boiling the sample with SDS during cell lysis, followed by dilution with thiourea/urea lysis buffer (2 M thiourea/ 7 M urea...

  9. Plasma lipid peroxidation and progression of disability in multiple sclerosis

    NARCIS (Netherlands)

    Koch, M.; Mostert, J.; Arutjunyan, A. V.; Stepanov, M.; Teelken, A.; Heersema, D.; De Keyser, J.

    Oxidative stress has been implicated in the pathophysiology of multiple sclerosis (MS), but its relation to disease progression is uncertain. To evaluate the relationship of plasma lipid peroxidation with progression of disability in MS, we measured blood plasma fluorescent lipid peroxidation

  10. Uranium peroxide precipitate drying temperature relationships

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, C.; Dyck, B., E-mail: chick_rodgers@cameco.com [Cameco Corp., Saskatoon, SK (Canada)

    2010-07-01

    Cameco Corporation is in the process of revitalizing the mill at its Key Lake operation in northern Saskatchewan. The current Key Lake process employs ammonia stripping and ammonia precipitation. As part of the revitalization, the company is considering installing strong acid stripping in solvent extraction as used at its Rabbit Lake operation. This change would lead to using hydrogen peroxide for uranium precipitation. As part of the process evaluation, tests were carried out to study how changes in the temperature of an indirect fired dryer affected the properties of uranium peroxide [yellowcake] precipitate. This paper discusses the results of the test work, including the relationships between drying temperature and the following: (author)

  11. Rapid solubilization of insoluble phosphate by a novel environmental stress-tolerant Burkholderia vietnamiensis M6 isolated from ginseng rhizospheric soil.

    Science.gov (United States)

    Park, Ki-Hyun; Lee, O-Mi; Jung, Ho-Il; Jeong, Jin-Ha; Jeon, Young-Dong; Hwang, Dae-Youn; Lee, Chung-Yeol; Son, Hong-Joo

    2010-04-01

    We isolated and characterized novel insoluble phosphate (P)-solubilizing bacteria tolerant to environmental factors like high salt, low and high pHs, and low temperature. A bacterium M6 was isolated from a ginseng rhizospheric soil and confirmed to belong to Burkholderia vietnamiensis by BIOLOG system and 16S rRNA gene analysis. The optimal cultural conditions for the solubilization of P were 2.5% (w/v) glucose, 0.015% (w/v) urea, and 0.4% (w/v) MgCl(2).6H(2)O along with initial pH 7.0 at 35 degrees C. High-performance liquid chromatography analysis showed that B. vietnamiensis M6 produced gluconic and 2-ketogluconic acids. During the culture, the pH was reduced with increase in gluconic acid concentration and was inversely correlated with P solubilization. Insoluble P solubilization in the optimal medium was about 902 mg l(-1), which was approximately 1.6-fold higher than the yield in NBRIP medium (580 mg l(-1)). B. vietnamiensis M6 showed resistance against different environmental stresses like 10-45 degrees C, 1-5% (w/v) salt, and 2-11 pH range. The maximal concentration of soluble P produced by B. vietnamiensis M6 from Ca(3)(PO(4))(2), CaHPO(4), and hydroxyapatite was 1,039, 2,132, and 1,754 mg l(-1), respectively. However, the strain M6 produced soluble P with 20 mg l(-1) from FePO(4) after 2 days and 100 mg l(-1) from AlPO(4) after 6 days, respectively. Our results indicate that B. vietnamiensis M6 could be a potential candidate for the development of biofertilizer applicable to environmentally stressed soil.

  12. Plutonium(IV) peroxide formation in nitric medium and kinetics Pu(VI) reduction by hydrogen peroxide

    International Nuclear Information System (INIS)

    Maillard, C.; Adnet, J.M.

    2001-01-01

    Reduction of plutonium (VI) to Pu(IV) with hydrogen peroxide is a step in industrial processes used to purify plutonium nitrate solutions. This operation must be carefully controlled, in order to avoid any formation of the Pu(IV) peroxide green precipitate and to obtain exclusively Pu(IV). This led us to study the acidity and Pu and H 2 O 2 concentrations influences on the precipitate appearance and to perform a Pu(VI) reduction kinetic study on a wide range of acidities ([HNO 3 ]: 0.5 to 8 M), plutonium concentrations ([Pu(VI)]: 0.1 to 0.8 M) and [H 2 O 2 ]/[Pu(VI)] ratio (from 1 to 8). Thus, the domain of Pu(IV) peroxide formation and the reactional paths were established. With the exception of 0.5 M nitric acid medium, the kinetic curves show two distinct regims: the first one corresponds to an induction period where the Pu(VI) concentration doesn't change, the second corresponds to a linear decrease of Pu(VI). An increase of the temperature greatly accelerates the Pu(VI) reduction rate while [H 2 O 2 ]/[Pu(VI)] has almost no influence. The Pu(VI) total reduction time decreases when initial concentration of plutonium increases. By increasing nitric acid concentration from 0.5 M to 6 M, the total Pu(VI) reduction time decreases. This time increases when [HNO 3 ] varies from 6 M to 8 M. (orig.)

  13. Lignin-solubilizing ability of actinomycetes isolated from termite (Termitidae) gut.

    Science.gov (United States)

    Pasti, M B; Pometto, A L; Nuti, M P; Crawford, D L

    1990-01-01

    The lignocellulose-degrading abilities of 11 novel actinomycete strains isolated from termite gut were determined and compared with that of the well-characterized actinomycete, Streptomyces viridosporus T7A. Lignocellulose bioconversion was followed by (i) monitoring the degradation of [14C]lignin- and [14C]cellulose-labeled phloem of Abies concolor to 14CO2 and 14C-labeled water-soluble products, (ii) determining lignocellulose, lignin, and carbohydrate losses resulting from growth on a lignocellulose substrate prepared from corn stalks (Zea mays), and (iii) quantifying production of a water-soluble lignin degradation intermediate (acid-precipitable polymeric lignin). The actinomycetes were all Streptomyces strains and could be placed into three groups, including a group of five strains that appear superior to S. viridosporus T7A in lignocellulose-degrading ability, three strains of approximately equal ability, and three strains of lesser ability. Strain A2 was clearly the superior and most effective lignocellulose decomposer of those tested. Of the assays used, total lignocellulose weight loss was most useful in determining overall bioconversion ability but not in identifying the best lignin-solubilizing strains. A screening procedure based on 14CO2 evolution from [14C-lignin]lignocellulose combined with measurement of acid-precipitable polymeric lignin yield was the most effective in identifying lignin-solubilizing strains. For the termite gut strains, the pH of the medium showed no increase after 3 weeks of growth on lignocellulose. This is markedly different from the pattern observed with S. viridosporus T7A, which raises the medium pH considerably. Production of extracellular peroxidases by the 11 strains and S. viridosporus T7A was followed for 5 days in liquid cultures.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2167628

  14. Assessing in vitro solubilization potential of different zinc solubilizing bacterial (zsb isolates Avaliação in vitro do potencial de solubilização de diferentes bactérias solubilizadoras de zinco (zsb

    Directory of Open Access Journals (Sweden)

    Venkatakrishnan Sivaraj Saravanan

    2004-06-01

    Full Text Available Zinc solubilizing ability of Bacillus sp. and Pseudomonas sp. was assessed using zinc oxide, zinc sulphide (sphalerite and zinc carbonate in both plate and broth assays. ZSB-O-1 (Bacillus sp. showed highest dissolution in the zinc sulphide (Sphalerite ore, with 2.80 cm of dissolution zone and 14.50 cm² of area in the plate assay and 13.60 mg kg-1 of zinc in the broth assay on the 15th day after inoculation. The ZSB-S-2 (Pseudomonas sp. showed more solubilizing ability in the zinc oxide, with 3.30 cm clearing zone and 20.43 cm² area in the plate assay and 16.40 mg kg-1 of zinc in the broth assay over the same inoculation period. The isolate ZSB-S-4 (Pseudomonas sp. has highest solubilizing potential in zinc carbonate with 6.20 cm of dissolution zone and 13.40 cm² area in the plate assay and 13.40 mg kg-1 of zinc in the broth assay. Thus, the solubilization potential varies among different cultures. The solubilization might be due to production of acids by the culture, since the pH of the culture broth has been shifted form 7.0-7.3 to 4.8-6.5 after 15 days of inoculation. The zinc tolerance limit for two cultures (ZSB-O-1 and ZSB-S-2 was studied and determined to be upto 100 mg kg-1 of zinc in the in vitro broth assay.A capacidade de Bacillus sp. e Pseudomonas sp. solubilizar zinco foi avaliada usando óxido de zinco, sulfeto de zinco e carbonato de zinco, em ensaios em placas e em caldo. A cultura ZSB-O-1 (Bacillus sp. apresentou maior dissolução no sulfeto de zinco, com 2,80 cm de zona de dissolução e 14,50 cm² de área no ensaio em placa e 13,60 mg kg-1 de zinco no ensaio em caldo, no 15º dia de incubação. A cultura ZSB-S-2 (Pseudomonas sp. apresentou maior capacidade de dissolução no óxido de zinco, com 3,30 cm de zona de dissolução e 20,43 cm² de área no ensaio em placa e 16,40 mg kg-1 de zinco no ensaio em caldo no mesmo período de inoculação. A cultura ZSB-S-4 (Pseudomonas sp. apresentou maior potencial de solubiliza

  15. Synthesis and Bioactivity of N-Benzoyl-N'-[5-(2'-substituted phenyl-2-furoyl] Semicarbazide Derivatives

    Directory of Open Access Journals (Sweden)

    Zining Cui

    2010-06-01

    Full Text Available In order to find novel chitin synthesis inhibitors (CSIs with good activity, benzoylphenylurea, a typical kind of CSIs, was chosen as the lead compound and 15 novel derivatives containing furan moieties were designed by converting the urea linkage of benzoylphenylureas into a semicarbazide and changing the aniline part into furoyl groups. The title compounds were synthesized by the reaction of substituted benzoyl isocyanates with 5-(substituted phenyl-2-furoyl hydrazine, and the structures were confirmed by IR, 1H-NMR, elemental analysis and single crystal X-ray diffraction analyses (compound E2. The bioassay results indicated that the title compounds exhibit good insecticidal activity, especially towards Plutella xylostella L., but had lower fungicidal activity. Inspiringly, the title compounds possessed obvious anticancer activity against human promyelocytic leukemic cell line (HL-60, and some of the title compounds also had activity against human hepatocellular carcinoma cell line (Bel-7402, human gastric carcinoma cell line (BGC-823, and human nasopharyngeal carcinoma cell line (KB. The results indicated that the linkage in the lead compounds was important to the bioactivity and spectra. The modification on the urea linkage is an effective strategy to discover new pesticide and drug candidates.

  16. Purification of benzoyl-mercapto-acetyl-tri-glycine and ethyl cysteinate dimer complemented with biological evaluations

    International Nuclear Information System (INIS)

    Robles, A.; Ramos, B.; Herrera, J.

    1999-01-01

    Purification of benzoyl-mercaptoacetyl triglycine (MAG3) and ethyl cysteinate dimer (L,L-ECD) has been conducted through fractionated recrystallization of its impurities and isomers; biological behavior of the main isomers has been evaluated through biological distribution in mice. Chemical purity of synthesized MAG3 is 69,9%; after purification, 98, 12% is obtained from the compound with adequate biological distribution; fusion points range between 194 and 196 o C before and after purification; recrystallization yields is 12%. Radiochemical purity of testing lot is 98%. In biological evaluations conducted in mice, injection dose percentages for the purest one, after 5 minutes, is 31,20% in kidneys and 1,14% in the liver. Chemical purity of synthesized ECD is 80,29%; after purification, 98,76% is obtained from the isomer with adequate biological activity; fusion points range between 195 and 197 o C; yield percentage in recrystallization is 29%. radiochemical purity of testing lot is 97%; in biological evaluations conducted in mice, injection dose percentages for the purest one, after 5 minutes, is 1,37% in the brain, 25,70% in the liver and 13,40% in kidneys

  17. Effect of microwaves on solubilization of organic fraction of municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Shahriari, H.; Warith, M.; Kennedy, K.J. [Ottawa Univ., Ottawa, ON (Canada). Dept. of Civil Engineering

    2009-07-01

    Landfilling is the most common method for disposing of municipal solid waste (MSW) in North America. MSW consists of nonbiodegradable fractions as well as biodegradable fractions known as the organic fraction of municipal solid waste (OFMSW). Because of its high moisture content, OFMSW produces large amounts of leachate in landfills. If not treated properly, leachates can pollute groundwater and negatively affect health and the environment. This paper reported on a study that was conducted to determine the effects of microwave (MW) irradiation on the solubilization of organic fraction of municipal solid waste (OFMSW) at different temperatures, MW ramp times, and supplemental water addition (SWA). The objective was to enhance solubilization before anaerobic digestion (AD). MW pretreatment resulted in higher soluble chemical oxygen demand (sCOD), proteins and sugars in the supernatant phase. The highest increase in sCOD was achieved at 175 degrees C. For the same condition, the free liquid volume from bound water released from OFMSW into the supernatant was about 1.39 times higher than the control. The increase in potentially bio-available sCOD increased significantly to more than 200 per cent after microwaving at high temperature. It was concluded that microwaving of OFMSW at high temperature with SWA provides the best conditions for waste solubilisation in preparation for anaerobic digestion. The actual effect of MW pre-treatment on the anaerobic digestion process has yet to be determined. 49 refs., 5 tabs., 3 figs.

  18. UV-C photolysis of endocrine disruptors. The influence of inorganic peroxides

    International Nuclear Information System (INIS)

    Rivas, Javier; Gimeno, Olga; Borralho, Teresa; Carbajo, Maria

    2010-01-01

    Norfloxacin, doxycycline and mefenamic acid have been photolysed with UV-C radiation (254 nm) in the presence and absence of inorganic peroxides (hydrogen peroxide or sodium monopersulfate). Quantum yields in the range (1.1-4.5) x 10 -3 mol Einstein -1 indicate the low photo-reactivity of these pharmaceuticals. Inorganic peroxides considerably enhanced the contaminants conversion, although no appreciable mineralization could be obtained. A simplistic reaction mechanism for the hydrogen peroxide promoted experiments allowed for a rough estimation of the rate constant between hydroxyl radicals and norfloxacin (k > 1 x 10 9 M -1 s -1 ), doxycycline (k > 1.5 x 10 9 M -1 s -1 ) and mefenamic acid (k > 11.0 x 10 9 M -1 s -1 ).

  19. Radiation-induced lipid peroxidation: influence of oxygen concentration and membrane lipid composition

    International Nuclear Information System (INIS)

    Wolters, H.; Tilburg, C.A.M. van; Konings, A.W.T.

    1987-01-01

    Radiation -induced lipid peroxidation phospholipid liposomes was investigated in terms of its dependence on lipid composition and oxygen concentration. Non-peroxidizable lipid incorporated in the liposomes reduced the rate of peroxidation of the peroxidizable phospholipid acyl chains, possibly by restricting the length of chain reactions. The latter effect is believed to be caused by interference of the non-peroxidizable lipids in the bilayer. At low oxygen concentration lipid peroxidation was reduced. The cause of this limited peroxidation may be a reduced number of radical initiation reactions possibly involving oxygen-derived superoxide radicals. Killing of proliferating mammalian cells, irradiated at oxygen concentrations ranging from 0 to 100%, appeared to be independent of the concentration of peroxidizable phospholipids in the cell membranes. This indicates that lipid peroxidation is not the determining process in radiation-induced reproductive cell death. (author)

  20. Hydrotropic solubilization of lipophilic drugs for oral delivery: The effects of urea and nicotinamide on carbamazepine solubility-permeability interplay

    Directory of Open Access Journals (Sweden)

    Avital Beig

    2016-10-01

    Full Text Available Hydrotropy refers to increasing the water solubility of otherwise poorly soluble compound by the presence of small organic molecules. While it can certainly increase the apparent solubility of a lipophilic drug, the effect of hydrotropy on the drugs' permeation through the intestinal membrane has not been studied. The purpose of this work was to investigate the solubility-permeability interplay when using hydrotropic drug solubilization. The concentration-dependent effects of the commonly used hydrotropes urea and nicotinamide, on the solubility and the permeability of the lipophilic antiepileptic drug carbamazepine were studied. Then, the solubility-permeability interplay was mathematically modeled, and was compared to the experimental data. Both hydrotropes allowed significant concentration-dependent carbamazepine solubility increase (up to ~30-fold. A concomitant permeability decrease was evident both in-vitro and in-vivo (~17-fold for nicotinamide and ~9-fold for urea, revealing a solubility-permeability tradeoff when using hydrotropic drug solubilization. A relatively simplified simulation approach based on proportional opposite correlation between the solubility increase and the permeability decrease at a given hydrotrope concentration allowed excellent prediction of the overall solubility-permeability tradeoff. In conclusion, when using hydrotropic drug solubilization it is prudent to not focus solely on solubility, but to account for the permeability as well; achieving optimal solubility-permeability balance may promote the overall goal of the formulation to maximize oral drug exposure.

  1. Hydrotropic Solubilization of Lipophilic Drugs for Oral Delivery: The Effects of Urea and Nicotinamide on Carbamazepine Solubility–Permeability Interplay

    Science.gov (United States)

    Beig, Avital; Lindley, David; Miller, Jonathan M.; Agbaria, Riad; Dahan, Arik

    2016-01-01

    Hydrotropy refers to increasing the water solubility of otherwise poorly soluble compound by the presence of small organic molecules. While it can certainly increase the apparent solubility of a lipophilic drug, the effect of hydrotropy on the drugs’ permeation through the intestinal membrane has not been studied. The purpose of this work was to investigate the solubility–permeability interplay when using hydrotropic drug solubilization. The concentration-dependent effects of the commonly used hydrotropes urea and nicotinamide, on the solubility and the permeability of the lipophilic antiepileptic drug carbamazepine were studied. Then, the solubility–permeability interplay was mathematically modeled, and was compared to the experimental data. Both hydrotropes allowed significant concentration-dependent carbamazepine solubility increase (up to ∼30-fold). A concomitant permeability decrease was evident both in vitro and in vivo (∼17-fold for nicotinamide and ∼9-fold for urea), revealing a solubility–permeability tradeoff when using hydrotropic drug solubilization. A relatively simplified simulation approach based on proportional opposite correlation between the solubility increase and the permeability decrease at a given hydrotrope concentration allowed excellent prediction of the overall solubility–permeability tradeoff. In conclusion, when using hydrotropic drug solubilization it is prudent to not focus solely on solubility, but to account for the permeability as well; achieving optimal solubility–permeability balance may promote the overall goal of the formulation to maximize oral drug exposure. PMID:27826241

  2. A comparative study on two explosive acetone peroxides

    Energy Technology Data Exchange (ETDEWEB)

    Egorshev, V. Yu.; Sinditskii, V.P., E-mail: vps@rctu.ru; Smirnov, S.P.

    2013-12-20

    Highlights: • The most accurate heats of DADP and TATP sublimation were evaluated from experimental vapor pressures in a widened temperature range. • DADP is more volatile while more thermally stable peroxide than TATP. • DADP reveals lesser sensitivity to drop-weight impact, flame temperature, burning rate, and initiating efficiency as compared with TATP. - Abstract: Two explosive cyclic acetone peroxides, diacetone diperoxide (DADP) and triacetone triperoxide (TATP) have been studied in respect of thermal decomposition, burning behavior, impact sensitivity, and initiating efficiency. Using the glass Bourdon gauge technique, the vapor pressures of TATP and DADP were determined over the temperature range 75–144 °C and 67–120 °C, respectively. The kinetic parameters of decomposition of the peroxides in the gas phase have been obtained in the temperature interval of 140–200 °C. The decomposition of both DADP and TATP followed the first-order reaction to high degrees of decay with close activation energies of 159.2 kJ/mol (38.0 kcal/mol) and 165.8 kJ/mol (39.6 kcal/mol), respectively. The decomposition rate constants of DADP were found to be approximately 2 times less than those of TATP. The linear burning rate of DADP measured in a constant-pressure window bomb appeared to be approximately 5 times less than that of TATP. Temperature profiles in the combustion wave were measured at subatmospheric pressures with the help of thin tungsten-rhenium thermocouples. The leading reaction on combustion of both volatile peroxides was assumed to occur in the gas phase. Kinetic parameters of the leading reaction derived from the combustion data showed a good agreement with kinetic parameters of low-temperature thermal decomposition extrapolated to the high-temperature flame zone. In the drop-weight impact test, DADP appeared to be notably less sensitive peroxide than TATP. No deflagration-to-detonation transition was observed when RDX was attempted to explode by

  3. Testing of a Peroxidation Systems, Inc. perox-pure SSB-30

    International Nuclear Information System (INIS)

    Hodgson, K.M.; Lunsford, T.R.

    1994-02-01

    A facility is being designed and built at the US Department of Energy (DOE) Hanford Site to treat water containing a variety of organic and inorganic compounds. An ultraviolet light/hydrogen peroxide system, manufactured by Peroxidation Systems, Inc. (PSI), has been chosen to destroy the organic compounds in the feed stream. The PSI perox-pure trademark model SSB-30 has been tested by the Westinghouse Hanford Company (WHC) to provide data for permit documentation and to determine appropriate operating conditions. The destruction of the organic compounds was demonstrated with several feed compositions at different ultraviolet light exposures and hydrogen peroxide concentrations

  4. Probing skin interaction with hydrogen peroxide using diffuse reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zonios, George [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Dimou, Aikaterini [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Galaris, Dimitrios [Laboratory of Biological Chemistry, School of Medicine, University of Ioannina, 45110 Ioannina (Greece)

    2008-01-07

    Hydrogen peroxide is an important oxidizing agent in biological systems. In dermatology, it is frequently used as topical antiseptic, it has a haemostatic function, it can cause skin blanching, and it can facilitate skin tanning. In this work, we investigated skin interaction with hydrogen peroxide, non-invasively, using diffuse reflectance spectroscopy. We observed transient changes in the oxyhaemoglobin and deoxyhaemoglobin concentrations as a result of topical application of dilute H{sub 2}O{sub 2} solutions to the skin, with changes in deoxyhaemoglobin concentration being more pronounced. Furthermore, we did not observe any appreciable changes in melanin absorption properties as well as in the skin scattering properties. We also found no evidence for production of oxidized haemoglobin forms. Our observations are consistent with an at least partial decomposition of hydrogen peroxide within the stratum corneum and epidermis, with the resulting oxygen and/or remaining hydrogen peroxide inducing vasoconstriction to dermal blood vessels and increasing haemoglobin oxygen saturation. An assessment of the effects of topical application of hydrogen peroxide to the skin may serve as the basis for the development of non-invasive techniques to measure skin antioxidant capacity and also may shed light onto skin related disorders such as vitiligo.

  5. Reactivity of lignin and lignin models towards UV-assisted peroxide

    International Nuclear Information System (INIS)

    Sun, Y.P.; Wallis, A.F.A.; Nguyen, K.L.

    1997-01-01

    The comparative reactivities of a series of guaiacyl and syringyl lignin model compounds and their methylated analogues towards alkaline peroxide and UV-alkaline peroxide were investigated. The overall reaction was followed by monitoring the reduction of the substrate as a function of time, and in every case, the reaction showed pseudo-first-order kinetics. The reaction rates of most lignin models having identical sidechains with alkaline peroxide and with UV-alkaline peroxide were in the order syringyl guaiacyl 3,4,5-trimethoxyphenyl veratryl. Thus phenols react faster than their methyl ethers, and an extra ortho methoxyl group promotes the reaction. Lignin models possessing electron-donating sidechains had generally higher reaction rates than those with electron-withdrawing sidechains. The reaction rates of the series of benzoic acids were 2-4 times higher at pH 11 than at pH 5. UV-peroxide degradation of a eucalypt kraft lignin was faster than that of a pine kraft lignin, and degradation was 1.4-1.6 times faster at pH 11 than at pH 5. The data are consistent with the formation of higher amounts of reactive radicals under alkaline conditions, and aromatic rings with greater electronegativities promoting reactions with the radicals

  6. Aluminum induces lipid peroxidation and aggregation of human blood platelets

    Directory of Open Access Journals (Sweden)

    T.J.C. Neiva

    1997-05-01

    Full Text Available Aluminum (Al3+ intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 µM stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA (100 µM and n-propyl gallate (NPG (100 µM, inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA (100 µM, an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation

  7. Precipitation of uranium concentrates by hydrogen peroxide

    International Nuclear Information System (INIS)

    Barbosa Filho, O.; Teixeira, L.A.C.

    1987-01-01

    An experimental study on the precipitation of uranyl peroxide (UO 4 x H 2 O) has been carried out in a laboratory scale. The objective was to assess the possibility of the peroxide route as an alternative to a conventional ammonium diuranate process. A factorial design was used to evaluate the effects of the initial pH, precipitation pH and H 2 O 2 /UO 2 2+ ratio upon the process. The responses were measured in terms of: efficiency of U precipitation, content of U in the precipitates, and distribution of impurities in the precipitates. (Author) [pt

  8. Radiation induced peroxidation in model lipid systems

    International Nuclear Information System (INIS)

    Dahlan, K.Z.B.H.M.

    1981-08-01

    In the studies of radiation induced lipid peroxidation, lecithin-liposomes and aqueous micellar solutions of sodium linoleate (or linoleic acid) have been used as models of lipid membrane systems. The liposomes and aqueous linoleate micelles were irradiated in the presence of O 2 and N 2 O/O 2 (80/20 v/v). The peroxidation was initiated using gamma radiation from 60 Co radiation source and was monitored by measuring the increase in absorbance of conjugated diene at 232 nm and by the thiobarbituric acid (TBA) test. The oxidation products were also identified by GLC and GLC-MS analysis. (author)

  9. Hydrogen peroxide and radiation water chemistry of boiling water reactors

    International Nuclear Information System (INIS)

    Ibe, E.; Watanabe, A.; Endo, M.; Takahashi, M.; Karasawa, H.

    1991-01-01

    G-values and rate constants at elevated temperature are reviewed and updated for computer simulation of water radiolysis in BWRs. Quantitative relationship between g-values of H 2 and OH was found out to govern numerically the radiolytic environment in the BWR primary system. Thermal decomposition of hydrogen peroxide was measured in stagnant water in a quartz cell and the rate constant was determined at 2.4 x 10 -7 s -1 with the activation energy of 53.3 kJ/mol. Behaviors of hydrogen peroxide under HWC simulated with updated variables were consistent with plant observation at Forsmark 1 and 2. The most likely decomposition scheme of hydrogen peroxide at surface was identified as H 2 O 2 → H + HO 2 . Based on the surface decomposition process, actual level of hydrogen peroxide was estimated at 200-400 ppb under NWC condition from measured at BWR sampling stations. The estimation was consistent with the numerical simulation of BWR water radiolysis with updated variables. (author)

  10. Dissolution kinetics of lead telluride in alkali solutions of hydrogen peroxide

    International Nuclear Information System (INIS)

    Danilova, M.G.; Sveshnikova, L.L.; Stavitskaya, T.A.; Repinskij, S.M.

    1991-01-01

    Dissolution kinetics of lead telluride in alkali solutions of hydrogen peroxide was investigated. Dependences of change of PbTe dissolution rate on concentration of hydrogen peroxide and alkali in the solution were obtained. It is shown that dissolution rate of lead telluride is affected by dissolution rate of lead oxide, representing the product of ReTe dissolution. The obtained regularities can be explained by change of solution structure with increase of KOH concentration and by the state of hydrogen peroxide in the solution

  11. Safer operating conditions and optimal scaling-up process for cyclohexanone peroxide reaction

    International Nuclear Information System (INIS)

    Zang, Na; Qian, Xin-Ming; Liu, Zhen-Yi; Shu, Chi-Min

    2015-01-01

    Highlights: • Thermal hazard of cyclohexanone peroxide reaction was measured by experimental techniques. • Levenberg–Marquardt algorithm was adopted to evaluate kinetic parameters. • Safer operating conditions at laboratory scale were acquired by BDs and TDs. • The verified safer operating conditions were used to obtain the optimal scale-up parameters applied in industrial plants. - Abstract: The cyclohexanone peroxide reaction process, one of the eighteen hazardous chemical processes identified in China, is performed in indirectly cooled semibatch reactors. The peroxide reaction is added to a mixture of hydrogen peroxide and nitric acid, which form heterogeneous liquid–liquid systems. A simple and general procedure for building boundary and temperature diagrams of peroxide process is given here to account for the overall kinetic expressions. Such a procedure has been validated by comparison with experimental data. Thermally safer operating parameters were obtained at laboratory scale, and the scaled-up procedure was performed to give the minimum dosing time in an industrial plant, which is in favor of maximizing industrial reactor productivity. The results are of great significance for governing the peroxide reaction process apart from the thermal runaway region. It also greatly aids in determining optimization on operating parameters in industrial plants.

  12. Enhanced solubilization of curcumin in mixed surfactant vesicles.

    Science.gov (United States)

    Kumar, Arun; Kaur, Gurpreet; Kansal, S K; Chaudhary, Ganga Ram; Mehta, S K

    2016-05-15

    Self-assemblies of equimolar double and single chain mixed ionic surfactants, with increasing numbers of carbon atoms of double chain surfactant, were analyzed on the basis of fluorescence and conductivity results. Attempts were also made to enhance the solubilization of curcumin in aqueous equimolar mixed surfactant systems. Mixed surfactant assembly was successful in retarding the degradation of curcumin in alkaline media (only 25-28 40% degraded in 10h at pH 13). Fluorescence spectroscopy and fluorescence quenching methods were employed to predict the binding position and mechanism of curcumin with self-assemblies. Results indicate that the interactions take place according to both dynamic and static quenching mechanisms and curcumin was distributed in a palisade layer of mixed aggregates. Antioxidant activity (using DPPH radical) and biocompatibility (using calf-thymus DNA) of curcumin-loaded mixed surfactant formulations were also evaluated. The prepared systems improved the stability, solubility and antioxidant activity of curcumin and additionally are biocompatible. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. effect of hydrogen peroxide and thiourea on dormancy breaking of ...

    African Journals Online (AJOL)

    ACSS

    the hydrogen peroxide (H2O2) (Claassens and. Vreugdenhil, 2000; Suttle, 2004). Hence, the objective of this study was to evaluate the effects of hydrogen peroxide and thiourea on dormancy and sprouting of potato microtubers and field grown tubers is described. MATERIELS AND METHODS. Production of microtubers.

  14. Saccharomyces cerevisiae has distinct adaptive responses to both hydrogen peroxide and menadione.

    OpenAIRE

    Jamieson, D J

    1992-01-01

    Treatment of Saccharomyces cerevisiae cells with low concentrations of either hydrogen peroxide or menadione (a superoxide-generating agent) induces adaptive responses which protect cells from the lethal effects of subsequent challenge with higher concentrations of these oxidants. Pretreatment with menadione is protective against cell killing by hydrogen peroxide; however, pretreatment with hydrogen peroxide is unable to protect cells from subsequent challenge with menadione. This suggests th...

  15. Effect of hydrothermal pre-treatment (HTP) on poultry slaughterhouse waste (PSW) sludge for the enhancement of the solubilization, physical properties, and biogas production through anaerobic digestion.

    Science.gov (United States)

    Park, Seyong; Yoon, Young-Man; Han, Seong Kuk; Kim, Daegi; Kim, Ho

    2017-06-01

    This study is an assessment of the hydrothermal pre-treatment (HTP) of poultry slaughterhouse waste (PSW) sludge for the enhancement of the solubilization, physical properties, and biogas production through anaerobic digestion. This assessment was carried out to ascertain the optimal HTP temperature. The solubilization and physical properties efficacy was investigated by capillary suction time (CST), time to filter (TTF), and particle size. In addition, the anaerobic digestion was investigated through biochemical methane potential (BMP) tests and subsequent statistical analysis using the modified Gompertz model. HTP was found to have improved the solubilization of the PSW sludge with increasing HTP temperature. In addition, the results of the CST, TTF, and particle size decreased with increasing HTP temperature. These results of the assessment that was conducted in this study confirm that the HTP process indeed modifies the physical properties of PSWs to enhance the solubilization of organic solids. Nevertheless, the results of the BMP tests and the modified Gompertz model analysis show that the optimal HTP temperature of PSWs for anaerobic digestion is 190°C. These findings show that to achieve high conversion efficiency, an accurately designed pre-treatment step must be included in the overall anaerobic digestion process for wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Solubilization of trace organics in block copolymer micelles for environmental separation using membrane extraction principles. Progress report, May 1, 1992--December 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Hatton, T.A.

    1992-12-01

    The solubilization of a range of polycyclic aromatic hydrocarbons in block copolymer micelles has been studied as a function of polymer composition, architecture, and temperature. Micelle formation is favored at high temperatures, leading to significant enhancements in solubilization capacity. At low temperatures, however, micelles do not form and the solubilization capacity of the block copolymer solution for the organics is low; this provides a convenient method for the regeneration of micellar solutions used as ``solvents`` in the treatment of contaminated feed streams using membrane extraction principles. It has also been shown (in collaboration with K.P. Johnston of University of Texas, Austin) that supercritical CO{sub 2} can be used effectively for micelle regeneration. Theoretical calculations of the structure of block copolymer micelles in the presence and absence of solutes using self-consistent mean-field lattice theories have successfully captured the trends observed with changing polymer composition and architecture, often quantitatively. The temperature and composition dependence of the micellar properties were determined by allowing the individual polymer segments to assume both polar and non-polar conformations.

  17. LIPID PEROXIDATION AND JOB STRESS IN DENTAL HEALTHCARE WORKERS

    Directory of Open Access Journals (Sweden)

    S. V. Melnikova

    2014-04-01

    Full Text Available This study devoted to the lipid peroxidation indices in dentists target group as a marker of psycho-emotional state. We revealed increase in the level of TBA-active products in female and male dentists during job stress. There was strong decrease in level of TBA-active products in control group of dentist that study during the lectures. Activation of lipid peroxidation in dentists during dentist examination can be considered as non-specific component of reactions towards the stressors of professional activities. We also revealed that the initial level of TBA-active products in female and male dentists before the outpatient dental reception was higher than that of dentists that study before lectures. This is indicates the mobilization of sympathetic nervous system before beginning of the working day. The contents of the level of TBA-active products in the oral fluid of female and male dentists after dental examination significantly increased, whereas these indices decreased in the group of dentists that study after the lectures. The increasing of TBA-active products in dentists after outpatient dental reception was by 42.5 % and 77 % higher compared with a group of dentists that study in the lecture classes. The results of correlation analysis suggest the influence of lipid peroxidation processes on the cardiovascular and blood system of dentists during job stress. Activation of lipid peroxidation in dentists during dental examination can be considered as non-specific component of the body's response to stressors influence in professional activities. Key words: dentists, activation of lipid peroxidation, psychoemotional stress, job stress.

  18. Test Excavations at Painted Rock Reservoir: Sites AZ Z:1:7, AZ Z:1:8, and AZ S:16:36.

    Science.gov (United States)

    1981-11-01

    were dehydrated, trimmed to 12-mm squares, and 77 78 placed in catalyzed (0.05-percent benzoyl peroxide), deinhibited acrylic monomer (50-percent methyl ...refrigeration for 72 hours in partially polymerized ethyl- methyl methacrylate. The methacrylate was polymerized at 50 degrees C and 50 p.s.i. nitrogen...pollen types from fill of Feature 10, AZ Z:l:8 Pollen Type Percent Pinus spp. 0.5 Cheno-Am 92.0 Gramineae 2.0 Ambrosia spp. 0.5 Malvaceae 0.5 Zea spp. 2.0

  19. Structure and characteristics of acid and pepsin-solubilized collagens from the skin of cobia (Rachycentron canadum).

    Science.gov (United States)

    Zeng, Shaokui; Yin, Juanjuan; Yang, Shuqi; Zhang, Chaohua; Yang, Ping; Wu, Wenlong

    2012-12-01

    Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were extracted from the skin of cobia (Rachycentron canadum). The yields of ASC and PSC were 35.5% and 12.3%, respectively. Based on the protein patterns and carboxymethyl-cellulose chromatography, ASC and PSC were composed of α1α2α3 heterotrimers and were characterised as type I collagen with no disulfide bond. Their amounts of imino acids were 203 and 191 residues per 1000 residues, respectively. LC-MS/MS analysis demonstrated the high sequences similarities of ASC and PSC. Fourier transform infrared spectroscopy spectra showed that the amide I, II and III peaks of PSC were obtained at a lower wave number compared with ASC. The thermal denaturation temperatures of ASC and PSC, as measured by viscometry, were 34.62 and 33.97°C, respectively. The transition temperatures (T(max)) were 38.17 and 36.03°C, respectively, as determined by differential scanning calorimetry (DSC). Both collagens were soluble at acidic pH and below 2% (w/v) NaCl concentration. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Synthesis of N-benzoyl-[α-14C]-N'-phenyl-2,6-diaminobenzoic acid and N-benzoyl-N'-phenyl-[3'-3H]-2,6-diaminobenzoic acid, and their absorption, excretion, and distribution in rats and guinea pigs

    International Nuclear Information System (INIS)

    Baba, Shigeo; Kuroki, Michitake; Kasuya, Yasuji; Suzuki, Kenji.

    1975-01-01

    N-benzoyl-N'-phenyl-2, 6-diaminobenzoic acid (F-1) is a new anti-inflammatory agent. Two isotopically labeled compounds of F-1 ( 3 H-F-1 and 14 C-F-1) were synthesized and their absorption and distribution were investigated in rats and guinea pigs. When 3 H-F-1 was orally administered to rats and guinea pigs, about 20% of the administered radioactivity was excreted in the urine and approximately 70% of it was excreted in the feces during 7 days after 3 H-F-1 administration. A higher concentration of 3 H-F-1 in the blood was observed in rats than in guinea pigs. The maximum blood concentration of 3 H-activity appeared one hour after the oral administration of 3 H-F-1 to rats, while in guinea pigs in appeared three hours later. These facts are in good agreement with the difference in the anti-inflammatory effect between rats and guinea pigs. The highest concentration of 3 H-activity in various organs, such as liver, adrenal, kidney, and lung, was found three hours after the oral administration of 3 H-F-1. (auth.)

  1. Lipid Peroxidation and Antioxidant Status in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Rokeya Begum

    2011-07-01

    Full Text Available Background: Preeclampsia is the most common and major medical complication of pregnancy with a high incidence of maternal and foetal morbidity and mortality. During pregnancy abnormally increased lipid peroxidation and free radical formation as well as significantly decreased antioxidants production in maternal blood may lead to pathogenesis of preeclampsia. So, we designed this study as little information is known about lipid peroxidation and antioxidant level in preeclampsia. Objectives: To assess the serum malondialdehyde (MDA level as a lipid peroxidation product and vitamin E (antioxidant level in women with preeclampsia as well as in normal pregnancy and to compare the values. Materials and Methods: The study was conducted on 60 women aged from 25 to 35 years in the department of Biochemistry, Budi Kemuliaan Maternity Hospital (BKMH in Jakarta during the period April to July 2004. Twenty were normal pregnant women and 20 were preeclamptic patients. For comparison age matched 20 apparently healthy nonpregnant women were included in the study. The study subjects were selected from outpatient department (OPD of Obstetrics and Gynaecology of BKMH in Jakarta. Serum MDA (lipid peroxidation product level was measured by thiobarbituric acid reactive substances assay (TBRAS method and vitamin E was estimated spectroflurometrically. Data were analyzed by unpaired Student’s t test between the groups by using SPSS version 12. Results: The mean serum MDA levels were significantly higher in normal pregnancy and also in preeclampsia than that of nonpregnant control group women (p<0.001. Again the serum MDA levels were significantly higher in preeclampsia than that of normal pregnant women (p<0.001. The serum vitamin E levels were significantly lower in preeclampsia and also in normal pregnancy than that of nonpregnant control women (p<0.001. Moreover, the serum vitamin E levels were significantly lower in preeclampsia compared to that of normal

  2. Lipid peroxidation and ascorbic acid levels in Nigeria children with ...

    African Journals Online (AJOL)

    This study was undertaken to establish data on the roles of lipid peroxidation and ascorbic acid in the pathology of malaria in Nigeria children. We measured the levels of malondialdehyde (MDA), a marker of lipid peroxidation and ascorbic acid in the plasma of 406 parasitaemic and 212 non-parasitaemic Nigerian children.

  3. Can aqueous hydrogen peroxide be used as a stand-alone energy source?

    International Nuclear Information System (INIS)

    Disselkamp, Robert S.

    2010-01-01

    A novel electrochemical scheme to convert a stand-alone supply of aqueous hydrogen peroxide into a fuel cell-ready stream of hydrogen gas plus aqueous hydrogen peroxide is described. The electrochemical cell, consisting of a solid base and solid acid electrocatalyst, together with a proton exchange membrane, comprise the system that converts aqueous hydrogen peroxide into separate gas streams of oxygen and hydrogen. Aqueous hydrogen peroxide is contained in the anode compartment only and exists in the region where oxygen gas is formed, whereas the cathode compartment is where hydrogen gas is generated and therefore exists in a reduced state. A near zero theoretical over-potential can be achieved by the choice of basicity and acidity of the electrode materials. The primary cost of the electrochemical cell is electrode construction and the aqueous hydrogen peroxide energy storage compound. Additional research effort is required to experimentally validate the concept and explore the full economic impact should initial studies, based on the design presented here, prove promising. (author)

  4. Peroxide reduction by a metal-dependent catalase in Nostoc punctiforme (cyanobacteria).

    Science.gov (United States)

    Hudek, L; Torriero, A A J; Michalczyk, A A; Neilan, B A; Ackland, M L; Bräu, Lambert

    2017-05-01

    This study investigated the role of a novel metal-dependent catalase (Npun_R4582) that reduces hydrogen peroxide in the cyanobacterium Nostoc punctiforme. Quantitative real-time PCR showed that npun_R4582 relative mRNA levels were upregulated by over 16-fold in cells treated with either 2 μM added Co, 0.5 μM added Cu, 500 μM Mn, 1 μM Ni, or 18 μM Zn. For cells treated with 60 μM H 2 O 2 , no significant alteration in Npun_R4582 relative mRNA levels was detected, while in cells treated with Co, Cu, Mn, Ni, or Zn and 60 μM peroxide, relative mRNA levels were generally above control or peroxide only treated cells. Disruption or overexpression of npun_R4582 altered sensitivity to cells exposed to 60 μM H 2 O 2 and metals for treatments beyond the highest viable concentrations, or in a mixed metal solution for Npun_R4582 - cells. Moreover, overexpression of npun_R4582 increased cellular peroxidase activity in comparison with wild-type and Npun_R4582 - cells, and reduced peroxide levels by over 50%. The addition of cobalt, manganese, nickel, and zinc increased the capacity of Npun_R4582 to reduce the rate or total levels of peroxide produced by cells growing under photooxidative conditions. The work presented confirms the function of NpunR4582 as a catalase and provides insights as to how cells reduce potentially lethal peroxide levels produced by photosynthesis. The findings also show how trace elements play crucial roles as enzymatic cofactors and how the role of Npun_R4582 in hydrogen peroxide breakdown is dependent on the type of metal and the level available to cells.

  5. Determination of amino acid and protein peroxides by the xylenol orange-Fe(III) complex

    International Nuclear Information System (INIS)

    Collins, J.; Craig, G.; Gebicki, J.

    1996-01-01

    Oxidative stress imposed on living organisms is believed to lead to the depletion of their antioxidant defences, followed by chemical changes in the cell constituents. These may ultimately develop into pathological conditions such as cancer or cardiovascular disease. An assay of peroxides which could be applied to tissues or simple tissue extracts would prove extremely useful in the studies of the phenomenon of oxidative stress. With this purpose, the authors have tested the ability of two peroxide assay techniques to measure the formation of amino acid and protein peroxides in aqueous solutions irradiated with gamma rays, using a modification of the method based on the oxidation of Fe(II)) by peroxides and complexing of the Fe(III) produced by xylenol orange. The molar extinction coefficients of the peroxides tested were determined by comparison with the well-tested iodometric assay. This work was extended to the detection of all organic peroxides in human blood plasma or serum subjected to oxidative stress, where the iodometric assay proved difficult to apply and unreliable because of the binding of iodine to the blood components. Preliminary results suggest that exposure of serum to gamma radiation leads to immediate peroxidation of the proteins, with a delay before generation of lipid peroxides

  6. Uranium precipitation with hydrogen peroxide

    International Nuclear Information System (INIS)

    Brown, R.A.

    1980-01-01

    Although hydrogen peroxide precipitation of uranium continues to be used primarily as means of producing a high purity yellowcake, it has also become an important process due to its superior physical properties. Processing costs such as filtering, drying and/or calcining and drumming, can be reduced. 5 refs

  7. Heterologous expression of pyrroloquinoline quinone (pqq) gene cluster confers mineral phosphate solubilization ability to Herbaspirillum seropedicae Z67.

    Science.gov (United States)

    Wagh, Jitendra; Shah, Sonal; Bhandari, Praveena; Archana, G; Kumar, G Naresh

    2014-06-01

    Gluconic acid secretion mediated by the direct oxidation of glucose by pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenase (GDH) is responsible for mineral phosphate solubilization in Gram-negative bacteria. Herbaspirillum seropedicae Z67 (ATCC 35892) genome encodes GDH apoprotein but lacks genes for the biosynthesis of its cofactor PQQ. In this study, pqqE of Erwinia herbicola (in plasmid pJNK1) and pqq gene clusters of Pseudomonas fluorescens B16 (pOK53) and Acinetobacter calcoaceticus (pSS2) were over-expressed in H. seropedicae Z67. Transformants Hs (pSS2) and Hs (pOK53) secreted micromolar levels of PQQ and attained high GDH activity leading to secretion of 33.46 mM gluconic acid when grown on 50 mM glucose while Hs (pJNK1) was ineffective. Hs (pJNK1) failed to solubilize rock phosphate, while Hs (pSS2) and Hs (pOK53) liberated 125.47 μM and 168.07 μM P, respectively, in minimal medium containing 50 mM glucose under aerobic conditions. Moreover, under N-free minimal medium, Hs (pSS2) and Hs (pOK53) not only released significant P but also showed enhanced growth, biofilm formation, and exopolysaccharide (EPS) secretion. However, indole acetic acid (IAA) production was suppressed. Thus, the addition of the pqq gene cluster, but not pqqE alone, is sufficient for engineering phosphate solubilization in H. seropedicae Z67 without compromising growth under nitrogen-fixing conditions.

  8. Sodium Borohydride/Hydrogen Peroxide Fuel Cells For Space Application

    Science.gov (United States)

    Valdez, T. I.; Deelo, M. E.; Narayanan, S. R.

    2006-01-01

    This viewgraph presentation examines Sodium Borohydride and Hydrogen Peroxide Fuel Cells as they are applied to space applications. The topics include: 1) Motivation; 2) The Sodium Borohydride Fuel Cell; 3) Sodium Borohydride Fuel Cell Test Stands; 4) Fuel Cell Comparisons; 5) MEA Performance; 6) Anode Polarization; and 7) Electrode Analysis. The benefits of hydrogen peroxide as an oxidant and benefits of sodium borohydride as a fuel are also addressed.

  9. Photocarcinogenesis and toxicity of benzoyl peroxide in hairless mice after simulated solar radiation

    DEFF Research Database (Denmark)

    Lerche, Catharina M; Philipsen, Peter A; Poulsen, Thomas

    2010-01-01

    hairless female C3.Cg/TifBomTac-immunocompetent mice. BPO or BPO-clin was applied topically to the back five times each week, followed by SSR three times each week (2, 3, or 4 standard erythema doses) 3-4 h later, for 365 days or until death. Generally BPO and BPO-clin did not accelerate the time to first...

  10. Photocarcinogenesis and toxicity of benzoyl peroxide in hairless mice after simulated solar radiation

    DEFF Research Database (Denmark)

    Lerche, Catharina M; Philipsen, Peter A; Poulsen, Thomas

    2010-01-01

    with UV radiation. BPO can promote skin tumorigenesis in a mouse skin chemical carcinogenesis model. As acne vulgaris is frequently localized on sun-exposed areas, we investigated whether BPO or BPO-clin accelerates photocarcinogenesis in combination with simulated solar radiation (SSR) in 12 groups of 25...

  11. Hydrogen peroxide as a fungicide for fish culture

    Science.gov (United States)

    Dawson, V.K.; Rach, J.J.; Schreier, Theresa M.

    1994-01-01

    Antifungal agents are needed to maintain healthy stocks of fish in the intensive culture systems currently employed in fish hatcheries. Malachite green has been the most widely used antifungal agent; however, its potential for producing teratology in animals and fish precludes further use in fish culture. Preliminary studies at the National Fisheries Research Center, La Crosse, WI, USA (La Crosse Center) indicate that hydrogen peroxide is effective for control of Saprolegnia sp. fungus on incubating eggs of rainbow trout. It is also effective against a wide variety of other organisms such as bacteria, yeasts, viruses, and spores, and has been proposed as a treatment for sea lice on salmon. Hydrogen peroxide and its primary decomposition products, oxygen and water, are not systemic poisons and are considered environmentally compatible. In response to a petition from the La Crosse Center, the U.S. Food and Drug Administration (FDA) recently classified hydrogen peroxide as a 'low regulatory priority' when used for control of fungus on fish and fish eggs. Preliminary tests conducted at the La Crosse Center suggest that prophylactic treatments of 250 to 500 ppm (based on 100% active ingredient) for 15 minutes every other day will inhibit fungal infections on healthy rainbow trout (Oncorhynchus mykiss) eggs. This treatment regime also seems to inhibit fungal development and increase hatching success among infected eggs. Efficacy and safety of hydrogen peroxide as a fungicide for fish are currently being evaluated.

  12. Nitrophenylboronic acids as highly chemoselective probes to detect hydrogen peroxide in foods and agricultural products.

    Science.gov (United States)

    Lu, Chun-Ping; Lin, Chieh-Ti; Chang, Ching-Ming; Wu, Shih-Hsiung; Lo, Lee-Chiang

    2011-11-09

    Hydrogen peroxide is commonly used in the food processing industry as a chlorine-free bleaching and sterilizing agent, but excessive amounts of residual hydrogen peroxide have led to cases of food poisoning. Here we describe the development of a novel nonenzymatic colorimetric method for the determination of residual hydrogen peroxide in foods and agricultural products. Nitrophenylboronic acids chemoselectively react with hydrogen peroxide under alkaline conditions to produce yellow nitrophenolates. Of the three nitrophenylboronic acid isomers tested, the p-isomer displayed the highest sensitivity for hydrogen peroxide and the fastest reaction kinetics. The reaction product, p-nitrophenolate, has an absorption maximum at 405 nm and a good linear correlation between the hydrogen peroxide concentration and the A(405) values was obtained. We successfully applied this convenient and rapid method for hydrogen peroxide determination to samples of dried bean curds and disposable chopsticks, thereby demonstrating its potential in foods and agricultural industries.

  13. Sol – Gel synthesis and characterization of magnesium peroxide nanoparticles

    International Nuclear Information System (INIS)

    Jaison, J; Chan, Y S; Ashok raja, C; Balakumar, S

    2015-01-01

    Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO 2 ) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO 2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles. (paper)

  14. A sensitive hydrogen peroxide sensor based on leaf-like silver

    International Nuclear Information System (INIS)

    Meng, Zuchao; Zhang, Mingyin; Zhang, Hongfang; Zheng, Jianbin

    2014-01-01

    A novel non-enzymatic hydrogen peroxide sensor based on leaf-like silver was constructed. The leaf-like silver was synthesized on the surface of L-cysteine (L-cys) by electrodeposition. Scanning electron microscopy and electrochemical techniques were used to characterize the leaf-like silver nanoparticles. The sensor showed high electrocatalytic activity towards the reduction of hydrogen peroxide. A wide linear range of 2.5–1.5 mM with a low detection limit of 0.7 µM was obtained. Excellent electrocatalytic activity, large surface-to-volume ratio and efficient electron transport properties of leaf-like silver have enabled stable and highly sensitive performance for the non-enzymatic hydrogen peroxide sensor. (paper)

  15. High levels of hydrogen peroxide in overnight tooth-whitening formulas: effects on enamel and pulp.

    Science.gov (United States)

    Pugh, George; Zaidel, Lynette; Lin, Nora; Stranick, Michael; Bagley, Daniel

    2005-01-01

    Limited data are available to assess the safety of high levels of hydrogen peroxide in overnight tooth-whitening formulas. The purpose of this study was to assess the effects of hydrogen peroxide on enamel microhardness, pulp penetration, and enamel morphology. Colgate Platinum Professional Overnight Whitening System (Colgate Oral Pharmaceuticals, Inc., Canton, MA, USA) (10% carbamide peroxide, equivalent to 3.5% hydrogen peroxide) was compared with two prototype formulations containing either 7.0% or 12.0% hydrogen peroxide. In the pulp chamber studies, human extracted teeth were exposed to 3.5%, 7.0%, or 12.0% hydrogen peroxide for 30 minutes, 4 hours, or 7 hours. Microhardness, electron spectroscopy for chemical analysis, and atomic force microscopy evaluations were made from enamel blocks cut from human extracted molars. The enamel blocks were evaluated following 14 7-hour treatments (98 h total). At 7 hours' post-treatment, hydrogen peroxide penetrated the pulp chamber at 23.12 +/- 10.09, 24.58 +/- 6.90, and 26.39 +/- 5.43 microg for 3.5%, 7.0%, and 12.0% hydrogen peroxide, respectively. With regard to enamel morphology, pulp penetration, microhardness, and elemental composition, no statistically significant differences were observed between treatment groups following 98 hours of treatment. Hydrogen peroxide does not adversely affect enamel morphology or microhardness. The levels recovered in pulp indicate that hydrogen peroxide is not expected to inhibit pulpal enzymes. Overnight tray products containing levels of hydrogen peroxide of 3.5%, 7.0%, and 12.0% are not expected to adversely affect the enamel or pulpal enzymes. Additional safety studies are needed to assess the potential for tooth sensitivity and gingival irritation.

  16. Changes in mitochondrial function by lipid peroxidation and their inhibition by biscoclaurin alkaloid

    International Nuclear Information System (INIS)

    Aono, K.; Shiraishi, N.; Arita, T.; Inouye, B.; Nakazawa, T.; Utsumi, K.

    1981-01-01

    During in vitro investigation of changes in mitochondrial function accompanying lipid peroxidation, it was found that cepharanthine, a biscoclaurin alkaloid, protects against such change. Results obtained were as follows: (1) Fe2+ induces lipid peroxidation of isolated mitochondria, resulting in diminished oxidative phosphorylation. (2) This diminishment largely depends on deterioration of ion compartmentation of the membrane and an increase in latent ATPase activity. (3) The Fe2+-induced deterioration in ion compartmentation is inhibited by cepharanthine. (4) Cepharanthine inhibits the mitochondrial lipid peroxidation induced by Fe2+. (5) Cepharanthine inhibits the lipid peroxidation of soybean lecithin liposomes by 60Co-irradiation

  17. Analisis sifat fisika pemanfaatan pati tandan kosong sawit dan limbah plastik LDPE sebagai bahan pembuatan plastik biodegradabel

    Directory of Open Access Journals (Sweden)

    Tengku Rachmi Hidayani

    2017-06-01

    Full Text Available This research aimed to overcome the issue of plastic packaging waste that accumulates in nature because synthetic polymers cannot be easily unraveled by bacteria. Biodegradable plastics were produced by mixing waste of plastics of the low density polyethylene (LDPE with starch of empty palm fruit bunches, modified with the addition of maleic anhydride as a crosslinking agent. To produce biodegradable plastics, different compositions of LDPE waste, starch of empty palm fruit bunch, maleic anhydride, and benzoyl peroxide were used, namely (90: 10: 1: 1, (80: 20: 1: 1, (70: 30: 1: 1, and (60: 40: 1: 1. Research stages consisted of extraction of starch from palm empty fruit bunch (PEFB; preparation of biodegradable plastic powder with the reflux method and xylene solvents; and making of biodegradable plastics using the press molding method. Based on the results of characterization, it was revealed that the optimum condition was generated by biodegradable plastics with the composition of LDPE waste, starch of empty palm bunches, maleic anhydride, and benzoyl peroxide was equal to 60: 40: 1: 1, which generated the tensile strength value of 6.9410 N/m2, the elongation at break of 3.1875%, the the melting point temperature of 103oC, and the decomposition temperature of 384oC. Besides, the thermal gravimetric test generated a residue of 12.6% and results of the analysis on morphological properties suggested that the starch distributed evenly.

  18. Electrochemical behaviour of platinum in hydrogen peroxide solution (1963)

    International Nuclear Information System (INIS)

    Prost, G.H.

    1963-06-01

    The relative stability of hydrogen peroxide in aqueous solution at 25 deg. C, allows its amperometric determination from the theory, using either its cathodic reduction or its anodic oxidation. The cathodic reduction yields a wave on a platinum electrode only when some oxygen is present in the solution. It cannot, therefore, be used for electrochemical determination. On the other hand, the anodic oxidation on platinum produces a wave which might be used. However, a passivation of platinum occurs at the same time. This passivation process is studied by means of potentio-kinetic, potentio-static, intensio-static curves and of pH measurements in the vicinity of the anode. A mechanism for passivation is presented, which takes into account the role of hydrogen peroxide as a reducing agent. This passivation rules out any analytical application of the oxidation reaction of hydrogen peroxide. (author) [fr

  19. Leaching of a Cu-Co ore from Congo using sulphuric acidhydrogen peroxide leachants

    Directory of Open Access Journals (Sweden)

    Seo S.Y.

    2013-01-01

    Full Text Available A Cu-Co ore from Katinga Province, the Republic of Congo containing 1.5% Co and 1.6% Cu was tested to determine the leachability of Cu and Co using sulphuric acid and hydrogen peroxide mixtures at different conditions. Without hydrogen peroxide, the maximum extraction of copper and cobalt were found to be ~80% and ~15%, respectively when the acid concentration was varied between 0.36 - 1.1M. When hydrogen peroxide was added (0.008-0.042M, Cu recovery was enhanced to ~90%. Recoveries of ~90% of Co could be achieved at 20ºC, using leachants consisting of 0.36M sulphuric acid and 0.025M hydrogen peroxide after 3 hours. The reaction time to reach 90% Co extraction was reduced to less than 2 hours at 30ºC. Stabcal modelling of the Eh-pH diagrams shows the importance of hydrogen peroxide as a reductant. The decrease of solution potential (300-350 mV by adding hydrogen peroxide was confirmed by Eh measurements during the tests. The leaching follows the shrinking core model kinetics, where the rate constant is linearly dependent on hydrogen peroxide concentration in the range 0-0.025M and proportional to (1/r2 where r is the average radius of the mineral particles. The activation energy for the leaching process is 72.3 kJ/mol.

  20. Overoxidation of chloroplast 2-Cys peroxiredoxins: balancing toxic and signaling activities of hydrogen peroxide

    Directory of Open Access Journals (Sweden)

    Leonor ePuerto-Galán

    2013-08-01

    Full Text Available Photosynthesis, the primary source of biomass and oxygen into the biosphere, involves the transport of electrons in the presence of oxygen and, therefore, chloroplasts constitute an important source of reactive oxygen species (ROS, including hydrogen peroxide. If accumulated at high level, hydrogen peroxide may exert a toxic effect; however, it is as well an important second messenger. In order to balance the toxic and signaling activities of hydrogen peroxide its level has to be tightly controlled. To this end, chloroplasts are equipped with different antioxidant systems such as 2-Cys peroxiredoxins (2-Cys Prxs, thiol-based peroxidases able to reduce hydrogen- and organic peroxides. At high peroxide concentrations the peroxidase function of 2-Cys Prxs may become inactivated through a process of overoxidation. This inactivation has been proposed to explain the signaling function of hydrogen peroxide in eukaryotes, whereas in prokaryotes, the 2-Cys Prxs of which were considered to be insensitive to overoxidation, the signaling activity of hydrogen peroxide is less relevant. Here we discuss the current knowledge about the mechanisms controlling 2-Cys Prx overoxidation in chloroplasts, organelles with an important signaling function in plants. Given the prokaryotic origin of chloroplasts, we discuss the occurrence of 2-Cys Prx overoxidation in cyanobacteria with the aim of identifying similarities between chloroplasts and their ancestors regarding their response to hydrogen peroxide.

  1. Peroxide coordination of tellurium in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Mikhaylov, Alexey A.; Medvedev, Alexander G. [Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow (Russian Federation); The Casali Center of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem (Israel); Churakov, Andrei V.; Grishanov, Dmitry A.; Prikhodchenko, Petr V. [Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow (Russian Federation); Lev, Ovadia [The Casali Center of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem (Israel)

    2016-02-15

    Tellurium-peroxo complexes in aqueous solutions have never been reported. In this work, ammonium peroxotellurates (NH{sub 4}){sub 4}Te{sub 2}(μ-OO){sub 2}(μ-O)O{sub 4}(OH){sub 2} (1) and (NH{sub 4}){sub 5}Te{sub 2}(μ-OO){sub 2}(μ-O)O{sub 5}(OH).1.28 H{sub 2}O.0.72 H{sub 2}O{sub 2} (2) were isolated from 5 % hydrogen peroxide aqueous solutions of ammonium tellurate and characterized by single-crystal and powder X-ray diffraction analysis, by Raman spectroscopy and thermal analysis. The crystal structure of 1 comprises ammonium cations and a symmetric binuclear peroxotellurate anion [Te{sub 2}(μ-OO){sub 2}(μ-O)O{sub 4}(OH){sub 2}]{sup 4-}. The structure of 2 consists of an unsymmetrical [Te{sub 2}(μ-OO){sub 2}(μ-O)O{sub 5}(OH)]{sup 5-} anion, ammonium cations, hydrogen peroxide, and water. Peroxotellurate anions in both 1 and 2 contain a binuclear Te{sub 2}(μ-OO){sub 2}(μ-O) fragment with one μ-oxo- and two μ-peroxo bridging groups. {sup 125}Te NMR spectroscopic analysis shows that the peroxo bridged bitellurate anions are the dominant species in solution, with 3-40 %wt H{sub 2}O{sub 2} and for pH values above 9. DFT calculations of the peroxotellurate anion confirm its higher thermodynamic stability compared with those of the oxotellurate analogues. This is the first direct evidence for tellurium-peroxide coordination in any aqueous system and the first report of inorganic tellurium-peroxo complexes. General features common to all reported p-block element peroxides could be discerned by the characterization of aqueous and crystalline peroxotellurates. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Solubilization and Humanization of Paraoxonase-1

    Directory of Open Access Journals (Sweden)

    Mohosin Sarkar

    2012-01-01

    Full Text Available Paraoxonase-1 (PON1 is a serum protein, the activity of which is related to susceptibility to cardiovascular disease and intoxication by organophosphorus (OP compounds. It may also be involved in innate immunity, and it is a possible lead molecule in the development of a catalytic bioscavenger of OP pesticides and nerve agents. Human PON1 expressed in E. coli is mostly found in the insoluble fraction, which motivated the engineering of soluble variants, such as G2E6, with more than 50 mutations from huPON1. We examined the effect on the solubility, activity, and stability of three sets of mutations designed to solubilize huPON1 with fewer overall changes: deletion of the N-terminal leader, polar mutations in the putative HDL binding site, and selection of the subset of residues that became more polar in going from huPON1 to G2E6. All three sets of mutations increase the solubility of huPON1; the HDL-binding mutant has the largest effect on solubility, but it also decreases the activity and stability the most. Based on the G2E6 polar mutations, we “humanized” an engineered variant of PON1 with high activity against cyclosarin (GF and found that it was still very active against GF with much greater similarity to the human sequence.

  3. Intestinal glutathione: determinant of mucosal peroxide transport, metabolism, and oxidative susceptibility

    International Nuclear Information System (INIS)

    Aw, Tak Yee

    2005-01-01

    The intestine is a primary site of nutrient absorption and a critical defense barrier against dietary-derived mutagens, carcinogens, and oxidants. Accumulation of oxidants like peroxidized lipids in the gut lumen can contribute to impairment of mucosal metabolic pathways, enterocyte dysfunction independent of cell injury, and development of gut pathologies, such as inflammation and cancer. Despite this recognition, we know little of the pathways of intestinal transport, metabolism, and luminal disposition of dietary peroxides in vivo or of the underlying mechanisms of lipid peroxide-induced genesis of intestinal disease processes. This chapter summarizes our current understanding of the determinants of intestinal absorption and metabolism of peroxidized lipids. I will review experimental evidence from our laboratory and others (Table 1) supporting the pivotal role that glutathione (GSH) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) play in mucosal transport and metabolism of lipid hydroperoxides and how reductant availability can be compromised under chronic stress such as hypoxia, and the influence of GSH on oxidative susceptibility, and redox contribution to genesis of gut disorders. The discussion is pertinent to understanding dietary lipid peroxides and GSH redox balance in intestinal physiology and pathophysiology and the significance of luminal GSH in preserving the integrity of the intestinal epithelium

  4. Diagnostics of Argon Injected Hydrogen Peroxide Added High Frequency Underwater Capillary Discharge

    Directory of Open Access Journals (Sweden)

    Muhammad Waqar Ahmed

    2016-05-01

    Full Text Available The effects of hydrogen peroxide addition and Argon injection on electrical and spectral characteristics of underwater capillary discharge were investigated. The flowing water discharge was created in a quartz tube (Φ = 4mm outer; Φ = 2mm inner; thickness 1mm by applying high frequency (25 kHz alternating current voltage (0-15kV across the tungsten electrodes (Φ=0.5mm, in pin-pin electrode configuration, separated by a gap distance of 10 mm. The results of no hydrogen peroxide addition and no Argon gas injection were compared with addition of hydrogen peroxide and Argon injection for different values. The emission spectrum was taken to present the increase in concentration of •OH radicals with and without hydrogen peroxide addition under different argon injection rates. The results demonstrated that addition of hydrogen peroxide do not remarkably affected the conductivity of water, but its addition increased the yield rate of •OH radicals generated by plasma discharge. The addition of Argon generated bubbles and gas channels reduced the high power consumption required for inducing flowing water long gap discharge. The results showed large concentration of •OH radicals due to hydrogen peroxide addition, less required input power for generating flowing water discharge by using high frequency input voltage and due to Argon injection.

  5. Tricalcium phosphate solubilization and nitrogen fixation by newly isolated Aneurinibacillus aneurinilyticus CKMV1 from rhizosphere of Valeriana jatamansi and its growth promotional effect

    Directory of Open Access Journals (Sweden)

    Anjali Chauhan

    Full Text Available Abstract Aneurinibacillus aneurinilyticus strain CKMV1 was isolated from rhizosphere of Valeriana jatamansi and possessed multiple plant growth promoting traits like production of phosphate solubilization (260 mg/L, nitrogen fixation (202.91 nmol ethylene mL-1 h-1, indole-3-acetic acid (IAA (8.1 µg/mL, siderophores (61.60%, HCN (hydrogen cyanide production and antifungal activity. We investigated the ability of isolate CKMV1 to solubilize insoluble P via mechanism of organic acid production. High-performance liquid chromatography (HPLC study showed that isolate CKMV1 produced mainly gluconic (1.34% and oxalic acids. However, genetic evidences for nitrogen fixation and phosphate solubilization by organic acid production have been reported first time for A. aneurinilyticus strain CKMV1. A unique combination of glucose dehydrogenase (gdh gene and pyrroloquinoline quinone synthase (pqq gene, a cofactor of gdh involved in phosphate solubilization has been elucidated. Nitrogenase (nif H gene for nitrogen fixation was reported from A. aneurinilyticus. It was notable that isolate CKMV1 exhibited highest antifungal against Sclerotium rolfsii (93.58% followed by Fusarium oxysporum (64.3%, Dematophora necatrix (52.71%, Rhizoctonia solani (91.58%, Alternaria sp. (71.08% and Phytophthora sp. (71.37%. Remarkable increase was observed in seed germination (27.07%, shoot length (42.33%, root length (52.6%, shoot dry weight (62.01% and root dry weight (45.7% along with NPK (0.74, 0.36, 1.82% content of tomato under net house condition. Isolate CKMV1 possessed traits related to plant growth promotion, therefore, could be a potential candidate for the development of biofertiliser or biocontrol agent and this is the first study to include the Aneurinibacillus as PGPR.

  6. Na,K-ATPase biostimulation by low-energy laser irradiation: comparative effects in membrane, solubilized and proteoliposomes enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Rigos, C.F.; Tedesco, A.C.; Ciancaglini, P. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Quimica; Santos, H.L. [Universidade Federal de Sao Joao Del Rei (UFSJ), MG (Brazil)

    2008-07-01

    Full text: The mechanism of laser irradiation action on living cells is not yet understood. The role of membrane ATPases as possible targets has been analyzed. In our group we have been working with Na,K-ATPase. This enzyme is a member of the P-type family of active cation transport proteins. Thus, the aim of the present work was to investigate the effect of low-energy laser irradiation (685 nm, 35 mW) on the ATPase activity of different forms of the Na,K-ATPase. Membrane-bound and solubilized (ab)2 form of Na,K-ATPase was obtained from the rabbit kidney and DPPC:DPPE-proteoliposomes were prepared by the co-solubilization method. Irradiations were carried out at 685 nm. The ATPase activity of the membrane fraction was not altered with exposition to irradiation doses between 4 and 24 J/c m2. With irradiation doses ranging from 32 to 40 J/c m2, a 28% increase on the ATPase activity was observed while when using up to 50 J/c m2 no additional enhancement was observed. When bio stimulation was done using the purified or the reconstituted enzyme, an increase of about 36-40% on the ATPase activity was observed using only 4-8 J/c m2. With irradiation above these values (24 J/c m2) no additional increase in the activity appeared. These studies revealed that the bio stimulation of ATPase activity from different forms of the Na,K -ATPase is dose dependent in different ranges of irradiation exposure. The stimulation promoted by visible laser doses was modulated and the process was reverted after 2 h for the enzyme present in the membrane and after about 5 h for the solubilized or the reconstituted in DPPC:DPPE-liposomes.

  7. Na,K-ATPase biostimulation by low-energy laser irradiation: comparative effects in membrane, solubilized and proteoliposomes enzyme

    International Nuclear Information System (INIS)

    Rigos, C.F.; Tedesco, A.C.; Ciancaglini, P.

    2008-01-01

    Full text: The mechanism of laser irradiation action on living cells is not yet understood. The role of membrane ATPases as possible targets has been analyzed. In our group we have been working with Na,K-ATPase. This enzyme is a member of the P-type family of active cation transport proteins. Thus, the aim of the present work was to investigate the effect of low-energy laser irradiation (685 nm, 35 mW) on the ATPase activity of different forms of the Na,K-ATPase. Membrane-bound and solubilized (ab)2 form of Na,K-ATPase was obtained from the rabbit kidney and DPPC:DPPE-proteoliposomes were prepared by the co-solubilization method. Irradiations were carried out at 685 nm. The ATPase activity of the membrane fraction was not altered with exposition to irradiation doses between 4 and 24 J/c m2. With irradiation doses ranging from 32 to 40 J/c m2, a 28% increase on the ATPase activity was observed while when using up to 50 J/c m2 no additional enhancement was observed. When bio stimulation was done using the purified or the reconstituted enzyme, an increase of about 36-40% on the ATPase activity was observed using only 4-8 J/c m2. With irradiation above these values (24 J/c m2) no additional increase in the activity appeared. These studies revealed that the bio stimulation of ATPase activity from different forms of the Na,K -ATPase is dose dependent in different ranges of irradiation exposure. The stimulation promoted by visible laser doses was modulated and the process was reverted after 2 h for the enzyme present in the membrane and after about 5 h for the solubilized or the reconstituted in DPPC:DPPE-liposomes

  8. Apparatus and method for treating pollutants in a gas using hydrogen peroxide and UV light

    Science.gov (United States)

    Cooper, Charles David (Inventor); Clausen, Christian Anthony (Inventor)

    2005-01-01

    An apparatus for treating pollutants in a gas may include a source of hydrogen peroxide, and a treatment injector for creating and injecting dissociated hydrogen peroxide into the flow of gas. The treatment injector may further include an injector housing having an inlet, an outlet, and a hollow interior extending therebetween. The inlet may be connected in fluid communication with the source of hydrogen peroxide so that hydrogen peroxide flows through the hollow interior and toward the outlet. At least one ultraviolet (UV) lamp may be positioned within the hollow interior of the injector housing. The at least one UV lamp may dissociate the hydrogen peroxide flowing through the tube. The dissociated hydrogen peroxide may be injected into the flow of gas from the outlet for treating pollutants, such as nitrogen oxides.

  9. HYDROGEN PEROXIDE PRODUCTION ACTIVITY AND ADHESIVE PROPERTIES OF AEROCOCCI, ISOLATED IN WOMEN

    Directory of Open Access Journals (Sweden)

    Stepanskyi D.O.

    2017-06-01

    Full Text Available Introduction. Antagonistic activity of probiotic microorganisms against other species of bacteria is an important mechanism of their ecology and it is widely used in practice. This activity is inherent in many heme-deficient bacteria, which include aerococci, and can be composed of several components: the production of organic acids, antibiotics, lysozyme, hydrogen peroxide and others. Ability to produce hydrogen peroxide under aerobic conditions and in a state of relative anaerobiosis was established in aerococci. They were divided into strong and weak producers, depending on the amount of peroxides. Lack of data about peroxide-productive ability of aerococci, isolated from the lower genital tract of women, as well as a proven mechanism of hydrogen peroxide excretion in the oxidation of lactic acid, led to need in studying the aerococci hydrogen peroxide production level, to create autobacterial drugs, based on aerococci symbiont strains for sanitation of birth canal. Colonization resistance of the vaginal mucous and normal microflora value depends largely on the degree of adhesion of microbial cells to the mucosal surface. Along with numerous studies of lactobacilli adhesive properties to the vaginal epithelium, there are no data on the adsorption capacity of aerococci to the vaginal epithelial cells. Material and methods. 18 aerococci resident strains and 1 museum strain were explored in total. Presence and quantity of autosymbiont aerococci content in different parts of the birth tract (cervical canal, vagina, external genitalia skin (EGS and perineum was studied in 44 healthy women. Isolation and identification of aerococci from the women body was conducted by the method, taking into account growth on selective indicator medium, growth and biochemical activity in environments with selenium and tellurium salts, lactate oxidase and superoxide dismutase activity. Hydrogen peroxide was determined by iodometric method. Hydrogen peroxide

  10. Graft copolymerization of a series of alkyl acrylates and alkyl methacrylates onto polyethylene

    International Nuclear Information System (INIS)

    Zurakowska-Orszagh, J.; Soerjosoeharto, K.; Busz, W.; Oldziejewski, J.

    1977-01-01

    Graft copolymerization of a series of alkyl acrylates and alkyl methacrylates into polyethylene of Polish production was investigated, using benzoyl peroxide as the initiator as well as preirradiation technique, namely ionizing radiation from a 60 Co γ-source. The effect of α-carbon methyl substituent of methacrylates as well as the influence of the length of alkyl chains in the ester groups of both series of monomers into the grafting process was observed. The ungrafted and some of the grafted polyethylene film obtained was studied by infrared spectrophotometry. (author)

  11. Structure and properties of poly(benzyl acrylate) synthesized under microwave energy

    Energy Technology Data Exchange (ETDEWEB)

    Oberti, Tamara G. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de La Plata-CONICET Casilla de Correo 16, Sucursal 4, 1900 La Plata (Argentina); Laboratorio de Estudio de Compuestos Organicos (LADECOR), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata (Argentina); Schiavoni, M. Mercedes [Laboratorio de Estudio de Compuestos Organicos (LADECOR), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata (Argentina); Cortizo, M. Susana [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de La Plata-CONICET Casilla de Correo 16, Sucursal 4, 1900 La Plata (Argentina)], E-mail: gcortizo@inifta.unlp.edu.ar

    2008-05-15

    Benzyl acrylate was polymerized under microwave irradiation using radical initiation (benzoyl peroxide, BP). The effect of the concentration of BP and power irradiation on the conversion, average molecular weights and the polydispersity index (M{sub w}/M{sub n}) were investigated. The {sup 1}H NMR and {sup 13}C NMR spectra analysis showed tendency to syndiotacticity and branched polymers were obtained at high conversion of reactions. A significant enhancement of the rates of polymerization and similar thermodynamic behavior, as compared with those obtained under thermal conditions was found.

  12. Preparation of permselective membranes by means of radiation induced grafting. Part of a coordinated programme on radiation modified polymers for biomedical and biochemical applications

    International Nuclear Information System (INIS)

    Lee, C.K.

    1982-09-01

    Styrene grafting to cellulose acetate membrane was studied to prepare a cellulose acetate reverse osmosis membrane with improved dimensional stability. The combination of cross-linking agents such as divinylbenzene or trimethyl propane triacrylate was found to increase the percentage of grafting. For the grafting of styrene:4-vinylpyridine:benzoyl peroxide mixture to cellulose acetate, the activation energy was determined to be 21.8 Kcal/mole over the range of 55-80 deg. C. The initial rate of grafting in % per hour was proportional to 0.76 power of dose intensities

  13. A study of the initiator concentration’s effect on styrene-divinylbenzene polymerization with iron particles

    Directory of Open Access Journals (Sweden)

    Bárbara M. da Conceição

    2011-01-01

    Full Text Available This paper describes the preparation of magnetic copolymer obtained from suspension polymerization of styrene (Sty and divinylbenzene (DVB in the presence of iron particles treated and not treated with oleic acid. The magnetic copolymers were characterized according to their morphology, particle size distribution and magnetic properties. The results show that incorporation of iron particles significantly changed the particles’ morphology. All samples presented higher saturation magnetization than the values reported in the literature and the particle size distribution was more monodisperse when the polymerization was conducted with 5%wt of benzoyl peroxide (BPO.

  14. Inactivation of possible micromycete food contaminants using the low-temperature plasma and hydrogen peroxide

    International Nuclear Information System (INIS)

    Čeřovský, M.; Khun, J.; Rusová, K.; Scholtz, V.; Soušková, H.

    2013-01-01

    The inhibition effect of hydrogen peroxide aerosol, low-temperature plasma and their combinations has been studied on several micromycetes spores. The low-temperature plasma was generated in corona discharges in the open air apparatus with hydrogen peroxide aerosol. Micromycete spores were inoculated on the surface of agar plates, exposed solely to the hydrogen peroxide aerosol, corona discharge or their combination. After incubation the diameter of inhibition zone was measured. The solely positive corona discharge exhibits no inactivation effect, the solely negative corona discharge and solely hydrogen peroxide aerosol exhibit the inactivation effect, however their combinations exhibit to be much more effective. Low-temperature plasma and hydrogen peroxide aerosol present a possible alternative method of microbial decontamination of food, food packages or other thermolabile materials

  15. Inactivation of possible micromycete food contaminants using the low-temperature plasma and hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Čeřovský, M., E-mail: scholtz@aldebaran.cz [Institute of Chemical Technology in Prague, Department of Food Preservation, Faculty of Food and Biochemical Technology (Czech Republic); Khun, J. [Institute of Chemical Technology in Prague, Department of Physics and Measurements, Faculty of Chemical Engineering (Czech Republic); Rusová, K. [Institute of Chemical Technology in Prague, Department of Food Preservation, Faculty of Food and Biochemical Technology (Czech Republic); Scholtz, V. [Institute of Chemical Technology in Prague, Department of Physics and Measurements, Faculty of Chemical Engineering (Czech Republic); Soušková, H. [Institute of Chemical Technology in Prague, Department of Computing and Control Engineering, Faculty of Chemical Engineering (Czech Republic)

    2013-09-15

    The inhibition effect of hydrogen peroxide aerosol, low-temperature plasma and their combinations has been studied on several micromycetes spores. The low-temperature plasma was generated in corona discharges in the open air apparatus with hydrogen peroxide aerosol. Micromycete spores were inoculated on the surface of agar plates, exposed solely to the hydrogen peroxide aerosol, corona discharge or their combination. After incubation the diameter of inhibition zone was measured. The solely positive corona discharge exhibits no inactivation effect, the solely negative corona discharge and solely hydrogen peroxide aerosol exhibit the inactivation effect, however their combinations exhibit to be much more effective. Low-temperature plasma and hydrogen peroxide aerosol present a possible alternative method of microbial decontamination of food, food packages or other thermolabile materials.

  16. Oxygen from Hydrogen Peroxide. A Safe Molar Volume-Molar Mass Experiment.

    Science.gov (United States)

    Bedenbaugh, John H.; And Others

    1988-01-01

    Describes a molar volume-molar mass experiment for use in general chemistry laboratories. Gives background technical information, procedures for the titration of aqueous hydrogen peroxide with standard potassium permanganate and catalytic decomposition of hydrogen peroxide to produce oxygen, and a discussion of the results obtained in three…

  17. Efficacy of Mouthwashes Containing Hydrogen Peroxide on Tooth Whitening

    OpenAIRE

    Karadas, Muhammet; Hatipoglu, Omer

    2015-01-01

    The aim of this study was to analyze the efficacy of mouthwashes containing hydrogen peroxide compared with 10% carbamide peroxide (CP) gel. Fifty enamel-dentin samples were obtained from bovine incisors and then stained in a tea solution. The stained samples were randomly divided into five groups according to the whitening product applied (n = 10): AS: no whitening (negative control), with the samples stored in artificial saliva; CR: Crest 3D White mouthwash; LS: Listerine Whitening mouthwas...

  18. Proteomic Analysis of Human Tendon and Ligament: Solubilization and Analysis of Insoluble Extracellular Matrix in Connective Tissues.

    Science.gov (United States)

    Sato, Nori; Taniguchi, Takako; Goda, Yuichiro; Kosaka, Hirofumi; Higashino, Kosaku; Sakai, Toshinori; Katoh, Shinsuke; Yasui, Natsuo; Sairyo, Koichi; Taniguchi, Hisaaki

    2016-12-02

    Connective tissues such as tendon, ligament and cartilage are mostly composed of extracellular matrix (ECM). These tissues are insoluble, mainly due to the highly cross-linked ECM proteins such as collagens. Difficulties obtaining suitable samples for mass spectrometric analysis render the application of modern proteomic technologies difficult. Complete solubilization of them would not only elucidate protein composition of normal tissues but also reveal pathophysiology of pathological tissues. Here we report complete solubilization of human Achilles tendon and yellow ligament, which is achieved by chemical digestion combined with successive protease treatment including elastase. The digestion mixture was subjected to liquid chromatography-mass spectrometry. The low specificity of elastase was overcome by accurate mass analysis achieved using FT-ICR-MS. In addition to the detailed proteome of both tissues, we also quantitatively determine the major protein composition of samples, by measuring peak area of some characteristic peptides detected in tissue samples and in purified proteins. As a result, differences between human Achilles tendon and yellow ligament were elucidated at molecular level.

  19. An Investigation on Rheology of Peroxide Cross-linking of Low Density Polyethylene

    DEFF Research Database (Denmark)

    Ghasemi, Ismaeil; Rasmussen, Henrik K.; Szabo, Peter

    2005-01-01

    One of the most important post-reactor modifications of polyethylene is cross-linking. It improves some properties of polyethylene such as environmental stress cracking resistance, chemical and abrasion resistance, and service temperature. In this study, the effect of peroxide cross-linking on th......One of the most important post-reactor modifications of polyethylene is cross-linking. It improves some properties of polyethylene such as environmental stress cracking resistance, chemical and abrasion resistance, and service temperature. In this study, the effect of peroxide cross......-linking on the rheological behaviour of low density polyethylene was investigated by using a combination of creep test and differential scanning calorimeter (DSC) in isotherm condition. The used peroxide was di-cumyl peroxide and its concentration was 2 wt%. The experiments were carried out at 150,160, and 170 degrees C...

  20. Siloxane-Terminated Solubilizing Side Chains: Bringing Conjugated Polymer Backbones Closer and Boosting Hole Mobilities in Thin-Film Transistors

    KAUST Repository

    Mei, Jianguo; Kim, Do Hwan; Ayzner, Alexander L.; Toney, Michael F.; Bao, Zhenan

    2011-01-01

    We introduce a novel siloxane-terminated solubilizing group and demonstrate its effectiveness as a side chain in an isoindigo-based conjugated polymer. An average hole mobility of 2.00 cm 2 V -1 s -1 (with a maximum mobility of 2.48 cm 2 V -1 s -1

  1. Alkaline peroxide pretreatment of corn stover: effects of biomass, peroxide, and enzyme loading and composition on yields of glucose and xylose

    Science.gov (United States)

    2011-01-01

    Background Pretreatment is a critical step in the conversion of lignocellulose to fermentable sugars. Although many pretreatment processes are currently under investigation, none of them are entirely satisfactory in regard to effectiveness, cost, or environmental impact. The use of hydrogen peroxide at pH 11.5 (alkaline hydrogen peroxide (AHP)) was shown by Gould and coworkers to be an effective pretreatment of grass stovers and other plant materials in the context of animal nutrition and ethanol production. Our earlier experiments indicated that AHP performed well when compared against two other alkaline pretreatments. Here, we explored several key parameters to test the potential of AHP for further improvement relevant to lignocellulosic ethanol production. Results The effects of biomass loading, hydrogen peroxide loading, residence time, and pH control were tested in combination with subsequent digestion with a commercial enzyme preparation, optimized mixtures of four commercial enzymes, or optimized synthetic mixtures of pure enzymes. AHP pretreatment was performed at room temperature (23°C) and atmospheric pressure, and after AHP pretreatment the biomass was neutralized with HCl but not washed before enzyme digestion. Standard enzyme digestion conditions were 0.2% glucan loading, 15 mg protein/g glucan, and 48 h digestion at 50°C. Higher pretreatment biomass loadings (10% to 20%) gave higher monomeric glucose (Glc) and xylose (Xyl) yields than the 2% loading used in earlier studies. An H2O2 loading of 0.25 g/g biomass was almost as effective as 0.5 g/g, but 0.125 g/g was significantly less effective. Optimized mixtures of four commercial enzymes substantially increased post-AHP-pretreatment enzymatic hydrolysis yields at all H2O2 concentrations compared to any single commercial enzyme. At a pretreatment biomass loading of 10% and an H2O2 loading of 0.5 g/g biomass, an optimized commercial mixture at total protein loadings of 8 or 15 mg/g glucan gave

  2. Inactivation of cellular caspases by peptide-derived tryptophan and tyrosine peroxides

    DEFF Research Database (Denmark)

    Hampton, Mark B; Morgan, Philip E; Davies, Michael Jonathan

    2002-01-01

    Peroxides generated on peptides and proteins within cells, as a result of radical attack or reaction with singlet oxygen, are longer-lived than H(2)O(2) due to their poor removal by protective enzymes. These peroxides readily oxidize cysteine residues and can inactivate thiol-dependent enzymes. W...

  3. Hydrogen peroxide: importance and determination

    OpenAIRE

    Mattos, Ivanildo Luiz de; Shiraishi, Karina Antonelli; Braz, Alexandre Delphini; Fernandes, João Roberto

    2003-01-01

    A brief discussion about the hydrogen peroxide importance and its determination is presented. It was emphasized some consideration of the H2O2 as reagent (separated or combined), uses and methods of analysis (techniques, detection limits, linear response intervals, sensor specifications). Moreover, it was presented several applications, such as in environmental, pharmaceutical, medicine and food samples.

  4. Hydrogen peroxide stimulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Ayano; Tanabe, Eriko; Inoue, Serina; Kitayoshi, Misaho; Okimoto, Souta; Hirane, Miku; Araki, Mutsumi [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

    2013-04-12

    Highlights: •Hydrogen peroxide stimulates cell motility of WB-F344 cells. •LPA{sub 3} is induced by hydrogen peroxide in WB-F344 cells. •Cell motility by hydrogen peroxide is inhibited in LPA{sub 3} knockdown cells. •LPA signaling is involved in cell migration by hydrogen peroxide. -- Abstract: Hydrogen peroxide which is one of reactive oxygen species (ROS) mediates a variety of biological responses, including cell proliferation and migration. In the present study, we investigated whether lysophosphatidic acid (LPA) signaling is involved in cell motile activity stimulated by hydrogen peroxide. The rat liver epithelial WB-F344 cells were treated with hydrogen peroxide at 0.1 or 1 μM for 48 h. In cell motility assays, hydrogen peroxide treated cells showed significantly high cell motile activity, compared with untreated cells. To measure the expression levels of LPA receptor genes, quantitative real time RT-PCR analysis was performed. The expressions of LPA receptor-3 (Lpar3) in hydrogen peroxide treated cells were significantly higher than those in control cells, but not Lpar1 and Lpar2 genes. Next, to assess the effect of LPA{sub 3} on cell motile activity, the Lpar3 knockdown cells from WB-F344 cells were also treated with hydrogen peroxide. The cell motile activity of the knockdown cells was not stimulated by hydrogen peroxide. Moreover, in liver cancer cells, hydrogen peroxide significantly activated cell motility of Lpar3-expressing cells, but not Lpar3-unexpressing cells. These results suggest that LPA signaling via LPA{sub 3} may be mainly involved in cell motile activity of WB-F344 cells stimulated by hydrogen peroxide.

  5. Impacts of heterogeneous reactions to atmospheric peroxides: Observations and budget analysis study

    Science.gov (United States)

    Qin, Mengru; Chen, Zhongming; Shen, Hengqing; Li, Huan; Wu, Huihui; Wang, Yin

    2018-06-01

    Atmospheric peroxides play important roles in atmospheric chemistry, acting as reactive oxidants and reservoirs of HOX and ROX radicals. Field measurements of atmospheric peroxides were conducted over urban Beijing from 2015 to 2016, including dust storm days, haze days and different seasons. We employed a box model based on RACM2 mechanism to conduct concentration simulation and budget analysis of hydrogen peroxide (H2O2) and peroxyacetic acid (PAA). In this study, heterogeneous reaction is found to be a significant sink for atmospheric H2O2 and PAA in urban Beijing. Here, we recommend a suitable uptake coefficient formula considering the water effect for model research of peroxides. It is found that H2O2 and PAA unexpectedly maintained considerable concentrations on haze days, even higher than that on non-haze days. This phenomenon is mainly ascribed to relatively high levels of volatile organic compounds and ozone on haze days. In addition, high levels of water vapor in pollution episode can promote not only the heterogeneous uptake to aerosol phase but also the production of H2O2. Atmospheric PAA formation is suggested to be sensitive to alkenes and NOX in urban Beijing. In particular, with the help of peroxides, sulfate formation rate from heterogeneous uptake could increase by ∼4 times on haze days, indicating the potential effect of peroxides on enhancement of aerosol oxidative property and secondary sulfate formation.

  6. Inactivation of animal and human prions by hydrogen peroxide gas plasma sterilization.

    Science.gov (United States)

    Rogez-Kreuz, C; Yousfi, R; Soufflet, C; Quadrio, I; Yan, Z-X; Huyot, V; Aubenque, C; Destrez, P; Roth, K; Roberts, C; Favero, M; Clayette, P

    2009-08-01

    Prions cause various transmissible spongiform encephalopathies. They are highly resistant to the chemical and physical decontamination and sterilization procedures routinely used in healthcare facilities. The decontamination procedures recommended for the inactivation of prions are often incompatible with the materials used in medical devices. In this study, we evaluated the use of low-temperature hydrogen peroxide gas plasma sterilization systems and other instrument-processing procedures for inactivating human and animal prions. We provide new data concerning the efficacy of hydrogen peroxide against prions from in vitro or in vivo tests, focusing on the following: the efficiency of hydrogen peroxide sterilization and possible interactions with enzymatic or alkaline detergents, differences in the efficiency of this treatment against different prion strains, and the influence of contaminating lipids. We found that gaseous hydrogen peroxide decreased the infectivity of prions and/or the level of the protease-resistant form of the prion protein on different surface materials. However, the efficiency of this treatment depended strongly on the concentration of hydrogen peroxide and the delivery system used in medical devices, because these effects were more pronounced for the new generation of Sterrad technology. The Sterrad NX sterilizer is 100% efficient (0% transmission and no protease-resistant form of the prion protein signal detected on the surface of the material for the mouse-adapted bovine spongiform encephalopathy 6PB1 strain and a variant Creutzfeldt-Jakob disease strain). Thus, gaseous or vaporized hydrogen peroxide efficiently inactivates prions on the surfaces of medical devices.

  7. Role of lipid peroxidation and oxidative stress in 3-methylindole pneumotoxicity

    International Nuclear Information System (INIS)

    Cary, M.G.

    1985-01-01

    The cytochrome P-450-catalyzed metabolism of 3-methylindole (3-MI) results in acute lung injury in ruminants and horses. Experiments were conducted to determine the role of lipid peroxidation and oxidative stress in 3-MI pneumotoxicity in goats. Goats were given methylethylketone peroxide (MEKP), a potent peroxidant, 3-MI, indole, or cremophor-EL vehicle. The levels of shortchain hydrocarbons in expired air were measured for 6 hours post-dosing by gas chromatography. Exhaled hydrocarbons increased 20 to 30 fold within 1 hour in goats given MEKP. No significant changes were seen in goats given 3-Mi, indole or cremophor-EL. Levels of thiobarbituric acid-reactive substances, an indicator of lipid peroxidation, were significantly increased in lung tissue from goats given MEKP. In goats given 3-MI, indole or cremophor-EL, the levels were not significantly different from each other. Goats were killed at 6 hours post-dosing and examined post mortem. Bronchiolar epithelial necrosis was seen in goats given 3-MI but there were not lung lesions in other groups. The role of oxygen radicals in 3-MI pneumotoxicity was examined in a goat lung explant system using 51 Cr release as an indicator of cytotoxicity. The results of these studies provide no evidence to support the view that 3-MI pneumotoxicity involves lipid peroxidation or oxidative stress as a result of formation of oxygen or xenobiotic radicals

  8. Characterization of the residues modified when F1 - ATPases are inactivated by 7-chloro-4-nitrobenzofurazan and 5'-[p-(fluorosulfonyl)benzoyl]-1,N6-ethenoadenosine

    International Nuclear Information System (INIS)

    Verburg, J.G.

    1989-01-01

    Inactivation of the F 1 -ATPases isolated from spinach chloroplasts (CF 1 ) and from the plasma membrane of the thermophilic bacterium, PS3 (TF 1 ) with 7-chloro-4-nitrobenzofurazan (Nbf-Cl) results in modification of Tyr-β-328 and Tyr-β-307, respectively. These residues are homologous to Tyr-β-311 of the F 1 -ATPase isolated from beef heart mitochondria, previously identified as the residue derivatized during inactivation of that enzyme with Nbf-Cl. Interestingly, an intramolecular migration of the Nbf- moiety from the tyrosine residue to a nearby lysine residue, observed when MF 1 and TF 1 which had been inactivated with Nbf-Cl are incubated at alkaline pH, was not observed when CF 1 was treated in the same manner. CF 1 differs from other ATPases in that it contains ADP, tightly bound at a single catalytic site. It is possible that this tightly bound ADP prevents migration of the Nbf moiety. The characteristics of inactivation of MF 1 with the fluorosulfonyl benzoyl derivatives of adenosine (FSBA) and inosine (FSBI) have been described in the literature. Inactivation of MF 1 with FSBA results in the mutually exclusive modification of Tyr-368 or His-427 in all three copies of the β subunit. These residues comprise part of the noncatalytic nucleotide binding site. Inactivation of MF 1 with FSBI results in modification of Tyr-β-345 in a single catalytic site. The fluorosulfonyl benzoyl derivative of 1,N 6 -ethenoadenosine (FSBεA) has been prepared, and the characteristics and selectivity of modification of MF 1 with this reagent are presented. FSBεA binds reversibly to MF 1 with an apparent dissociation constant of 250 μM before covalent modification. The residue in MF 1 that reacts with FSBεA exhibits an apparent pK a of 8.9

  9. Studies on Synthesis of Some Novel Heterocyclic Chalcone, Pyrazoline, Pyrimidine - 2 - One, Pyrimidine - 2 - Thione, para-Acetanilide Sulphonyl and Benzoyl Derivatives and their Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Rakesh N. Mistry

    2005-01-01

    Full Text Available 1, 2 - Dichloro benzene on chlorosulphonation by chlorosulphonic acid gives 1, 2 - [dichloro] - benzene sulphonyl chloride which on condensation with p –amino acetophenone gives 1-[acetyl] - 1’ , 2’ - [dichloro] - dibenz sulphonamide derivative. This derivative undergo condensation with 2,4- dichloro benzaldehyde gives 1- [3” - (sub. phenyl - 2” - propene - 1” - one] - 1’ , 2’ - [dichloro] - dibenz sulphonamide derivative which on reaction with 99% hydrazine hydrate and glacial acetic acid gives 1-[acetyl]-3- [1’ , 2’ - (dichloro - dibenz sulphonamide] -5 - [2” , 4” - dichloro phenyl] - 2 - pyrazoline derivative. This derivative reacts with various substituted aldehydes to give corresponding substituted chalcone derivatives [1(a-j]. Now, these chalcone derivatives [1(a-j] on condensation with urea gives corresponding substituted pyrimidine - 2 - one derivatives [2(a-j] and on condensation with thio-urea gives corresponding substituted pyrimidine- 2 -thione derivatives [3(a-j]. Further, these chalcone derivatives [1(a-j] on reaction with 99% hydrazine hydrate gives 1 - [1’ - (H - 5’ - (sub. phenyl - 2’ - pyrazoline]- 3 - [1” , 2” - (dichloro - dibenz sulphonamide] - 5 - [2’’’ , 4’’’ - dichloro phenyl]-2- pyrazoline derivatives [4(a-j] as an intermediate compounds, which on condensation with p-acetanilide sulphonyl chloride gives corresponding substituted p - acetanilide sulphonyl derivatives [5(a-j] and on condensation with benzoyl chloride gives corresponding substituted benzoyl derivatives [6(a-j]. Structure elucidation of synthesised compounds has been made on the basis of elemental analysis, I.R. spectral studies and 1H N.M.R. spectral studies. The antimicrobial activity of the synthesised compounds has been studied against the cultures “Staphylococcus aureus”, “Escherichia coli” and “Candela albicans”.

  10. Membrane lipid peroxidation by UV-A: Mechanism and implications

    International Nuclear Information System (INIS)

    Bose, B.; Agarwal, S.; Chatterjee, S.N.

    1990-01-01

    UV-A produced a dose-dependent linear increase of lipid peroxidation in liposomal membrane, as detected by the assay of (i) conjugated dienes, (ii) lipid hydroperoxides, (iii) malondialdehydes (MDA), and (iv) the fluorescent adducts formed by the reaction of MDA with glycine and also a linear dose-dependent increase of [ 14 C]glucose efflux from the liposomes. UV-A-induced MDA production could not be inhibited by any significant degree by sodium formate, dimethyl sulfoxide, EDTA, or superoxide dismutase but was very significantly inhibited by butylated hydroxytoluene, alpha-tocopherol, sodium azide, L-histidine, dimethylfuran, and beta-carotene. MDA formation increased with an increase in the D 2 O content in water, leading to a maximal amount of nearly 50% enhancement of lipid peroxidation in 100% D 2 O vis-a-vis water used as dispersion medium. The experimental findings indicate the involvement of singlet oxygen as the initiator of the UV-A-induced lipid peroxidation

  11. Cocrystal solubility-pH and drug solubilization capacity of sodium dodecyl sulfate – mass action model for data analysis and simulation to improve design of experiments

    Directory of Open Access Journals (Sweden)

    Alex Avdeef

    2018-06-01

    Full Text Available This review discusses the disposition of the anionic surfactant, sodium dodecyl sulfate (SDS; i.e., sodium lauryl sulfate, to solubilize sparingly-soluble drugs above the surfactant critical micelle concentration (CMC, as quantitated by the solubilization capacity (k. A compilation of 101 published SDS k values of mostly poorly-soluble drug molecules was used to develop a prediction model as a function of the drug’s intrinsic solubility, S0, and its calculated H-bond acceptor/donor potential. In almost all cases, the surfactant was found to solubilize the neutral form of the drug. Using the mass action model, the k values were converted to drug-micelle stoichiometric binding constants, Kn, corresponding to drug-micelle equilibria in drug-saturated solutions. An in-depth case study (data from published sources considered the micellization reactions as a function of pH of a weak base, B, (pKa 3.58, S0 52 μg/mL, where at pH 1 the BH.SDS salt was predicted to precipitate both below and above the CMC. At low SDS concentrations, two drug salts were predicted to co-precipitate: BH.Cl and BH.SDS. Solubility products of both were determined from the analysis of the reported solubility-surfactant data. Above the CMC, in a rare example, the charged form of the drug (BH+ appeared to be strongly solubilized by the surfactant. The constant for that reaction was also determined. At pH 7, the reactions were simpler, as only the neutral form of the drug was solubilized, to a significantly lesser extent than at pH 1. Case studies also featured examples of solubilization of solids in the form of cocrystals. For many cocrystal systems studied in aqueous solution, the anticipated supersaturated state is not long-lasting, as the drug component precipitates to a thermodynamically stable form, thus lowering the amount of the active ingredient available for intestinal absorption. Use of surfactant can prevent this. A recently-described method for predicting the

  12. Diverse Cd(II) compounds based on N-benzoyl-L-glutamic acid and N-donor ligands: Structures and photoluminescent properties

    International Nuclear Information System (INIS)

    Ma, Ning; Guo, Wei-Ying; Song, Hui-Hua; Yu, Hai-Tao

    2016-01-01

    Five new Cd(II) coordination polymers with N-benzoyl-L-glutamic acid (H_2bzgluO) and different N-donor ligands, [Cd(bzgluO)(2,2′-bipy)(H_2O)]_n (1), [Cd(bzgluO)(2,4′-bipy)_2(H_2O)·3H_2O]_n (2), [Cd(bzgluO)(phen)·H_2O]_n (3), [Cd(bzgluO)(4,4′-bipy)(H_2O)]_n (4), [Cd(bzgluO)(bpp)(H_2O)·2H_2O]_n (5) were synthesized (2,2′-bipy=2,2′-bipyridine, 2,4′-bipy=2,4′-bipyridine, phen=1,10-phenanthroline, 4,4′-bipy=4,4′-bipyridine, bpp=1,3-di(4-pyridyl)propane). Compounds 1–2 exhibit a 1D single-chain structure. Compound 1 generates a 2D supramolecular structure via π–π stacking and hydrogen bonding, 3D architecture of compound 2 is formed by hydrogen bonding. Compound 3 features a 1D double-chain structure, which are linked by π–π interactions into a 2D supramolecular layer. Compounds 4-5 display a 2D network structure. Neighboring layers of 4 are extended into a 3D supramolecular architecture through hydrogen bonding. The structural diversity of these compounds is attributed to the effect of ancillary N-donor ligands and coordination modes of H_2bzgluO. Luminescent properties of 1–5 were studied at room temperature. Circular dichroism of compounds 1, 2 and 5 were investigated. - Graphical abstract: Five new Cd(II) metal coordination compounds with H_2bzgluO and different N-donor ligands were synthesized and characterized. Compounds 1, 2 and 3 present 1D structures, compounds 4 and 5 display 2D networks. Results indicate that auxiliary ligands and coordination modes of H_2bzgluO play an important role in governing the formation of final frameworks, and the hydrogen-bonding and π–π stacking interactions contribute the formation of the diverse supramolecular architectures. Furthermore, the different crystal structures influence the emission spectra significantly. - Highlights: • It is rarely reported that complexes prepared with N-benzoyl-L-glutamic acid. • Each complex displays diverse structures and different supramolecular

  13. Method for processing powdery radioactive wastes

    International Nuclear Information System (INIS)

    Yasumura, Keijiro; Matsuura, Hiroyuki; Tomita, Toshihide; Nakayama, Yasuyuki.

    1978-01-01

    Purpose: To solidify radioactive wastes with ease and safety at a high reaction speed but with no boiling by impregnating the radioactive wastes with chlorostyrene. Method: Beads-like dried ion exchange resin, powdery ion exchange resin, filter sludges, concentrated dried waste liquor or the like are mixed or impregnated with a chlorostyrene monomer dissolving therein a polymerization initiator such as methyl ethyl ketone peroxide and benzoyl peroxide. Mixed or impregnated products are polymerized to solid after a predetermined of time through curing reaction to produce solidified radioactive wastes. Since inflammable materials are used, this process has a high safety. About 70% wastes can be incorporated. The solidified products have a strength as high as 300 - 400 kg/cm 3 and are suitable to ocean disposal. The products have a greater radioactive resistance than other plastic solidification products. (Seki, T.)

  14. Solubilization of poorly water-soluble drugs using solid dispersions.

    Science.gov (United States)

    Tran, Thao T-D; Tran, Phuong H-L; Khanh, Tran N; Van, Toi V; Lee, Beom-Jin

    2013-08-01

    Many new drugs have been discovered in pharmaceutical industry and exposed their surprised potential therapeutic effects. Unfortunately, these drugs possess low absorption and bioavailability since their solubility limitation in water. Solid dispersion (SD) is the current technique gaining so many attractions from scientists due to its effect on improving solubility and dissolution rate of poorly water-soluble drugs. A number of patents including the most recent inventions have been undertaken in this review to address various respects of this strategy in solubilization of poorly watersoluble drugs including type of carriers, preparation methods and view of technologies used to detect SD properties and mechanisms with the aim to accomplish a SD not only effective on enhanced bioavailability but also overcome difficulties associated with stability and production. Future prospects are as well discussed with an only hope that many developments and researches in this field will be successfully reached and contributed to commercial use for treatment as much as possible.

  15. Tricalcium phosphate solubilization and nitrogen fixation by newly isolated Aneurinibacillus aneurinilyticus CKMV1 from rhizosphere of Valeriana jatamansi and its growth promotional effect.

    Science.gov (United States)

    Chauhan, Anjali; Guleria, Shiwani; Balgir, Praveen P; Walia, Abhishek; Mahajan, Rishi; Mehta, Preeti; Shirkot, Chand Karan

    Aneurinibacillus aneurinilyticus strain CKMV1 was isolated from rhizosphere of Valeriana jatamansi and possessed multiple plant growth promoting traits like production of phosphate solubilization (260mg/L), nitrogen fixation (202.91nmolethylenemL -1 h -1 ), indole-3-acetic acid (IAA) (8.1μg/mL), siderophores (61.60%), HCN (hydrogen cyanide) production and antifungal activity. We investigated the ability of isolate CKMV1 to solubilize insoluble P via mechanism of organic acid production. High-performance liquid chromatography (HPLC) study showed that isolate CKMV1 produced mainly gluconic (1.34%) and oxalic acids. However, genetic evidences for nitrogen fixation and phosphate solubilization by organic acid production have been reported first time for A. aneurinilyticus strain CKMV1. A unique combination of glucose dehydrogenase (gdh) gene and pyrroloquinoline quinone synthase (pqq) gene, a cofactor of gdh involved in phosphate solubilization has been elucidated. Nitrogenase (nif H) gene for nitrogen fixation was reported from A. aneurinilyticus. It was notable that isolate CKMV1 exhibited highest antifungal against Sclerotium rolfsii (93.58%) followed by Fusarium oxysporum (64.3%), Dematophora necatrix (52.71%), Rhizoctonia solani (91.58%), Alternaria sp. (71.08%) and Phytophthora sp. (71.37%). Remarkable increase was observed in seed germination (27.07%), shoot length (42.33%), root length (52.6%), shoot dry weight (62.01%) and root dry weight (45.7%) along with NPK (0.74, 0.36, 1.82%) content of tomato under net house condition. Isolate CKMV1 possessed traits related to plant growth promotion, therefore, could be a potential candidate for the development of biofertiliser or biocontrol agent and this is the first study to include the Aneurinibacillus as PGPR. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  16. Hydrogen peroxide and caustic soda: Dancing with a dragon while bleaching

    Science.gov (United States)

    Peter W. Hart; Carl Houtman; Kolby Hirth

    2013-01-01

    When hydrogen peroxide is mixed with caustic soda, an auto-accelerating reaction can lead to generation of significant amounts of heat and oxygen. On the basis of experiments using typical pulp mill process concentration and temperatures, a relatively simple kinetic model has been developed. Evaluation of these model results reveals that hydrogen peroxide-caustic soda...

  17. Artificial photosynthesis for production of hydrogen peroxide and its fuel cells.

    Science.gov (United States)

    Fukuzumi, Shunichi

    2016-05-01

    The reducing power released from photosystem I (PSI) via ferredoxin enables the reduction of NADP(+) to NADPH, which is essential in the Calvin-Benson cycle to make sugars in photosynthesis. Alternatively, PSI can reduce O2 to produce hydrogen peroxide as a fuel. This article describes the artificial version of the photocatalytic production of hydrogen peroxide from water and O2 using solar energy. Hydrogen peroxide is used as a fuel in hydrogen peroxide fuel cells to make electricity. The combination of the photocatalytic H2O2 production from water and O2 using solar energy with one-compartment H2O2 fuel cells provides on-site production and usage of H2O2 as a more useful and promising solar fuel than hydrogen. This article is part of a Special Issue entitled Biodesign for Bioenergetics--The design and engineering of electronc transfer cofactors, proteins and protein networks, edited by Ronald L. Koder and J.L. Ross Anderson. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Changes in brown coal structure caused by coal-solubilizing microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Schmiers, H.; Koepsel, R.; Weber, A.; Winkelhoefer, M.; Grosse, S. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Energieverfahrenstechnik und Chemieingenieurwesen

    1997-12-31

    The phenomenon of coal solubilization caused by microorganisms has been explained by various mechanisms: extraction of non-covalently bonded polar components of the coal substance by biogenic agents (chelating agents, alkaline substances) and enzyme-catalyzed cleavage of covalent bonds by extracellular enzyme systems. For this it is assumed that bond cleavage occurs on the aliphatic carbon (methylene groups, aliphatic bridges or on ester groups). As the coal has usually been treated with oxidizing agents such as H{sub 2}O{sub 2} or HNO{sub 3} before bioconversion, there is a possibility that the result of bioconversion is overlaid with the effect of the chemical treatment. We therefore studied the structural changes in the organic coal substance during pre-oxidation with H{sub 2}O{sub 2}, treatment with MnP and conversion using the fungal strains of Trichoderma and Fusarium oxysporum. (orig.)

  19. Alkaline peroxide pretreatment of corn stover: effects of biomass, peroxide, and enzyme loading and composition on yields of glucose and xylose

    Directory of Open Access Journals (Sweden)

    Hodge David B

    2011-06-01

    Full Text Available Abstract Background Pretreatment is a critical step in the conversion of lignocellulose to fermentable sugars. Although many pretreatment processes are currently under investigation, none of them are entirely satisfactory in regard to effectiveness, cost, or environmental impact. The use of hydrogen peroxide at pH 11.5 (alkaline hydrogen peroxide (AHP was shown by Gould and coworkers to be an effective pretreatment of grass stovers and other plant materials in the context of animal nutrition and ethanol production. Our earlier experiments indicated that AHP performed well when compared against two other alkaline pretreatments. Here, we explored several key parameters to test the potential of AHP for further improvement relevant to lignocellulosic ethanol production. Results The effects of biomass loading, hydrogen peroxide loading, residence time, and pH control were tested in combination with subsequent digestion with a commercial enzyme preparation, optimized mixtures of four commercial enzymes, or optimized synthetic mixtures of pure enzymes. AHP pretreatment was performed at room temperature (23°C and atmospheric pressure, and after AHP pretreatment the biomass was neutralized with HCl but not washed before enzyme digestion. Standard enzyme digestion conditions were 0.2% glucan loading, 15 mg protein/g glucan, and 48 h digestion at 50°C. Higher pretreatment biomass loadings (10% to 20% gave higher monomeric glucose (Glc and xylose (Xyl yields than the 2% loading used in earlier studies. An H2O2 loading of 0.25 g/g biomass was almost as effective as 0.5 g/g, but 0.125 g/g was significantly less effective. Optimized mixtures of four commercial enzymes substantially increased post-AHP-pretreatment enzymatic hydrolysis yields at all H2O2 concentrations compared to any single commercial enzyme. At a pretreatment biomass loading of 10% and an H2O2 loading of 0.5 g/g biomass, an optimized commercial mixture at total protein loadings of 8 or 15 mg

  20. Test of Lignin and Cellulose Decomposition and Phosphate Solubilization by Soil Fungi of Gunung Halimun

    OpenAIRE

    Suciatmih, Suciatmih

    2001-01-01

    In order to know the capability of lignin and cellulose degradation and phosphate solubilization by soil fungi of Gunung Halimun National Park, a study was carried out to qualitatively analyse its physiological properties. Out of 35 soil fungi tested, 1 species that belonged to Basidiomycetes degraded lignin, 32 species degraded cellulose, and 31 species dissolved inorganic phosphate.The presence of soil fungi that degraded cellulose and dissolved phosphate could be used as a candidate for bi...