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1.
Food Chem ; 248: 210-216, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329846

RESUMO

An enzymatic process was developed for the preparation of a nutritionally enriched 1,3-diacylglycerol(DAG)-rich oil from a blend of refined sunflower and rice bran oils. The process involves hydrolysis of vegetable oil blend using Candida cylindracea followed by esterification with glycerol using Lipozyme RM1M. The resultant DAG-rich oil contains 84% of DAG (66% of 1,3-DAG, 18% of 1,2-DAG) and 16% of triacylglycerol (TAG) along with micro nutrients like γ-oryzanol, tocotrienols, tocopherols and phytosterols. Nutritional studies of the DAG-rich oil were conducted in Wistar rats and compared with sunflower oil (SFO). The calorific value of the DAG-rich oil was estimated to be 6.45 Kcals/g as against 9.25 Kcals/g for SFO. The serum and liver cholesterol and TAG levels in rats fed with 1,3-DAG-rich oil were found to be significantly reduced as compared to rats fed diet containing SFO. We conclude that 1,3-DAG-rich oil is a low calorie fat and exhibits hypolipidemic effects.


Assuntos
Diglicerídeos/química , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Óleo de Farelo de Arroz/química , Óleo de Girassol/química , Animais , Restrição Calórica , Candida , Colesterol/sangue , Colesterol/metabolismo , Esterificação , Lipase/química , Lipase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Fitosteróis/análise , Ratos , Ratos Wistar , Tocoferóis/análise , Triglicerídeos/análise , Triglicerídeos/metabolismo
2.
Eur J Med Chem ; 120: 86-96, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27187861

RESUMO

A highly concise and expedient total synthesis of bioactive clavaminols (1-4) has been executed using commercially available achiral compound decanol. The synthetic strategy relied on trans-Wittig olefination, Sharpless asymmetric epoxidation, regioselective azidolysis and in situ detosylation followed by reduction as key reactions with good overall yield. Based on biological evaluation studies of all the synthesized compounds, it was observed that the clavaminol A (1) exhibited good cytotoxicity against DU145 and SKOV3 cell lines with IC50 value of 10.8 and 12.5 µM, respectively. Clavaminol A (1) and deacetyl clavaminol H (3) displayed selective promising inhibition towards Gram-positive pathogenic bacterial strains and showed good antifungal activity against the tested Candida strains. In addition, compounds 1 and 3 have demonstrated significant bactericidal activity. Compound 3 was found to be equipotent to the standard drug Miconazole displaying MFC value of 15.6 µg/mL against Candida albicans MTCC 854, C. albicans MTCC 1637, C. albicans MTCC 3958 and Candida glabrata MTCC 3019. Compounds 1 and 3 were also able to inhibit the biofilm formation of Micrococcus luteus MTCC 2470 and Staphylococcus aureus MLS16 MTCC 2940. Clavaminol A (1) increased the levels of reactive oxygen species (ROS) accumulation in M. luteus MTCC 2470.


Assuntos
Antibacterianos/química , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Ceramidas/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/fisiologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ceramidas/síntese química , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/análise
3.
Eur J Med Chem ; 118: 98-106, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27128176

RESUMO

A conceptual synthetic approach of short-chain C12-sphinganine 1 and a small library of its 1,2,3-triazole analogs 2(a-f) has been accomplished using the commercially available and inexpensive 10-undecenoic acid as a starting material. Miyashita's C-2 selective endo mode azidolysis and Huisgen click reaction was employed for the synthesis of the designed analogs. Based on biological evaluation studies of all the synthesized compounds, it was observed that, (2S,3R)-2-(4-(3-hydroxyphenyl)-1H-1,2,3-triazol-1-yl)dodecan-1,3-diol (2b) exhibited promising antimicrobial and antifungal activities. Furthermore, compound 2b was able to inhibit the biofilm formation of Candida albicans MTCC 227, Micrococcus luteus MTCC 2470 and Staphylococcus aureus MTCC 96 with IC50 values of 1.9, 2.1 and 2.9 µg/mL, respectively. Compound 2b increased the levels of reactive oxygen species (ROS) in C. albicans MTCC 227.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Desenho de Fármacos , Esfingosina/análogos & derivados , Triazóis/síntese química , Triazóis/farmacologia , Anti-Infecciosos/química , Candida albicans/citologia , Candida albicans/efeitos dos fármacos , Candida albicans/metabolismo , Candida albicans/fisiologia , Técnicas de Química Sintética , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Micrococcus luteus/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Esfingosina/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Triazóis/química
4.
Bioresour Technol ; 188: 99-102, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25777067

RESUMO

Solid acid catalysts can hydrolyze cellulose with lower reaction times and are easy to recover and reuse. A glycerol based carbon acid catalyst developed at CSIR-IICT performed well in acid catalysis reactions and hence this study was undertaken to evaluate the catalyst for hydrolysis of biomass (alkali pretreated or native rice straw). The catalyst could release 262 mg/g total reducing sugars (TRS) in 4h at 140 °C from alkali pretreated rice straw, and more importantly it released 147 mg/g TRS from native biomass. Reusability of the catalyst was also demonstrated. Catalytic hydrolysate was used as sugar source for fermentation to produce ethanol. Results indicate the solid acid catalyst as an interesting option for biomass hydrolysis.


Assuntos
Biomassa , Biotecnologia/métodos , Carbono/química , Etanol/química , Carboidratos/química , Catálise , Fermentação , Glicerol/química , Hidrólise , Oryza , Saccharomyces cerevisiae/enzimologia , Temperatura
5.
Bioresour Technol ; 153: 370-3, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24373712

RESUMO

Simultaneous esterification and transesterification method is employed for the preparation of biodiesel from 7.5% free fatty acid (FFA) containing karanja (Pongamia glabra) oil using water resistant and reusable carbon-based solid acid catalyst derived from glycerol in a single step. The optimum reaction parameters for obtaining biodiesel in >99% yield by simultaneous esterification and transesterification are: methanol (1:45 mole ratio of oil), catalyst 20wt.% of oil, temperature 160°C and reaction time of 4h. After the reaction, the catalyst was easily recovered by filtration and reused for five times with out any deactivation under optimized conditions. This single-step process could be a potential route for biodiesel production from high FFA containing oils by simplifying the procedure and reducing costs and effluent generation.


Assuntos
Biocombustíveis , Ácidos Graxos/metabolismo , Glicerol/metabolismo , Óleos de Plantas/metabolismo , Pongamia/química , Reciclagem , Ácidos Sulfônicos/farmacologia , Carbono/farmacologia , Catálise/efeitos dos fármacos , Esterificação/efeitos dos fármacos , Metanol/análise , Pongamia/efeitos dos fármacos , Temperatura , Fatores de Tempo
6.
Food Chem ; 142: 144-51, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24001824

RESUMO

An improved sample preparation using dispersive solid-phase extraction clean-up was proposed for the trace level determination of 35 multiclass pesticide residues (organochlorine, organophosphorus and synthetic pyrethroids) in edible oils. Quantification of the analytes was carried out by gas chromatography-mass spectrometry in negative chemical ionisation mode (GC-NCI-MS/MS). The limit of detection and limit of quantification of residues were in the range of 0.01-1ng/g and 0.05-2ng/g, respectively. The analytes showed recoveries between 62% and 110%, and the matrix effect was observed to be less than 25% for most of the pesticides. Crude edible oil samples showed endosulfan isomers, p,p'-DDD, α-cypermethrin, chlorpyrifos, and diazinon residues in the range of 0.56-2.14ng/g. However, no pesticide residues in the detection range of the method were observed in refined oils.


Assuntos
Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Óleos de Plantas/análise , Extração em Fase Sólida/métodos , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/isolamento & purificação , Compostos Organofosforados/análise , Compostos Organofosforados/isolamento & purificação , Espectrometria de Massas em Tandem/métodos
7.
Eur J Med Chem ; 67: 384-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23911578

RESUMO

The first total synthesis of clavaminol-G (1) and 1-aminoundecan-2-ol (2) has been achieved from 10-undecenoic acid using epoxidation, regioselective azidolysis and in situ detosylation and reduction reactions as key steps. The methodology is extended for the synthesis of 1-aminoundecan-2-ol derivatives; namely, methyl 11-amino-10-hydroxyundecanoate (3), 11-amino-10-hydroxyundecanoic acid (4) and 11-aminoundecan-1,10-diol (5). Among these, 1-aminoundecan-2-ol (2) exhibited good antimicrobial activity and promising cytotoxicity towards HeLa, MDA-MB-231, MCF-7 and A549 cell lines with IC50 values of 4.36, 4.02, 3.88 and 6.78 µM, respectively. Compound 3 exhibited good activity against HeLa cells (IC50 = 3.59 µM), while compound 5 showed moderate activity towards HeLa and A549 cell lines. Clavaminol G (1) and compound 4 showed no activity towards all the cell lines.


Assuntos
Acetamidas/farmacologia , Alcanos/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Acetamidas/síntese química , Acetamidas/química , Alcanos/síntese química , Alcanos/química , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/efeitos dos fármacos , Células HeLa , Humanos , Células MCF-7 , Estrutura Molecular , Relação Estrutura-Atividade
8.
Bioresour Technol ; 119: 306-11, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22750497

RESUMO

The present study demonstrates the production of biodiesel from used cooking oil containing high free fatty acid by a two-step heterogeneously catalyzed process. The free fatty acids were first esterified with methanol using a 25 wt.% TPA/Nb(2)O(5) catalyst followed by transesterification of the oil with methanol over ZnO/Na-Y zeolite catalyst. The catalysts were characterized by XRD, FT-IR, BET surface area and CO(2)-TPD. In the case of transesterification the effect of reaction parameters, such as catalyst concentration, methanol to oil molar ratio and reaction temperature, on the yield of ester were investigated. The catalyst with 20 wt.% ZnO loading on Na-Y exhibited the highest activity among the others. Both the solid acid and base catalysts were found to be reusable for several times indicating their efficacy in the two-step process.


Assuntos
Biocombustíveis , Ácidos Graxos não Esterificados/química , Metanol/química , Óleos/química , Zeolitas/química , Catálise , Culinária , Esterificação
9.
Bioorg Med Chem Lett ; 22(14): 4678-80, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22704888

RESUMO

We report the total synthesis of (2S,3R)-2-aminododecan-3-ol has been achieved starting from commercially available 10-undecenoic acid. The key steps involved are Sharpless asymmetric epoxidation, Miyashita's boron-directed C-2 regioselective azidolysis, generated the asymmetric centers and in situ detosylation and reduction of azido tosylate. The antifungal activity of the synthesized (2S,3R)-2-aminododecan-3-ol was evaluated on several Candida strains and was comparable to miconazole, a standard drug.


Assuntos
Antifúngicos/síntese química , Dodecanol/análogos & derivados , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Dodecanol/síntese química , Dodecanol/farmacologia , Estrutura Molecular
10.
Bioresour Technol ; 116: 53-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22609655

RESUMO

Biodiesel synthesis from rice bran fatty acids (RBFA) was carried out using cesium exchanged 12-tungstophosphoric acid (TPA) catalysts. The physico-chemical properties of the catalysts were derived from X-ray diffraction (XRD), Fourier transform infrared (FTIR), temperature programmed desorption (TPD) of NH(3) and scanning electron microscopy (SEM). The characterization techniques revealed that the Keggin structure of TPA remained intact as Cs replaced protons. The partial exchange of Cs for protons resulted in an increase in acidity and the catalysts with one Cs(+) (Cs(1)H(2)PW(12)O(40)) showed highest acidity. Under optimized conditions about 92% conversion of RBFA was obtained. The catalyst was reused for five times and retained of its original activity. Pseudo-first order model was applied to correlate the experimental kinetic data. Modified tungstophosphoric acids are efficient solid acid catalysts for the synthesis of biodiesel from the oils containing high FFA.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Césio/metabolismo , Ácidos Graxos/metabolismo , Oryza/química , Ácidos Fosfóricos/metabolismo , Compostos de Tungstênio/metabolismo , Resíduos/análise , Catálise , Esterificação , Cinética , Reciclagem , Propriedades de Superfície , Temperatura , Fatores de Tempo
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