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1.
Braz. j. microbiol ; 45(3): 903-910, July-Sept. 2014. ilus, graf
Artigo em Inglês | LILACS | ID: lil-727019

RESUMO

A soil screened Bacillus flexus XJU-1 was induced to simultaneously produce alkaline amylase, alkaline lipase and alkaline protease at their optimum levels on a common medium under submerged fermentation. The basal cultivation medium consisted of 0.5% casein, 0.5% starch and 0.5% cottonseedoil as an inducer forprotease, amylase, and lipase, respectively. The casein also served as nitrogen source for all 3 enzymes. The starch was also found to act as carbon source additive for both lipase and protease. Maximum enzyme production occurred on fermentation medium with 1.5% casein, 1.5% soluble starch, 2% cottonseed oil, 2% inoculum size, initial pH of 11.0, incubation temperature of 37 °C and 1% soybean meal as a nitrogen source supplement. The analysis of time course study showed that 24 h was optimum incubation time for amylase whereas 48 h was the best time for both lipase and protease. After optimization, a 3.36-, 18.64-, and 27.33-fold increase in protease, amylase and lipase, respectively was recorded. The lipase was produced in higher amounts (37.72 U/mL) than amylase and protease about 1.27 and 5.85 times, respectively. As the 3 enzymes are used in detergent formulations, the bacterium can be commercially exploited to secrete the alkaline enzymes for use in detergent industry. This is the first report for concomitant production of 3 alkaline enzymes by a bacterium.


Assuntos
Amilases/metabolismo , Bacillus/enzimologia , Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Detergentes/metabolismo , Endopeptidases/metabolismo , Inibidores Enzimáticos/metabolismo , Lipase/metabolismo , Bacillus/crescimento & desenvolvimento , Bacillus/isolamento & purificação , Carbono/metabolismo , Meios de Cultura/química , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Microbiologia do Solo , Temperatura , Fatores de Tempo
2.
J. venom. anim. toxins incl. trop. dis ; 20: 1-8, 04/02/2014. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484564

RESUMO

Snakebites are considered a neglected tropical disease that affects thousands of people worldwide. Although antivenom is the only treatment available, it is associated with several side effects. As an alternative, plants have been extensively studied in order to obtain an alternative treatment. In folk medicine, Azima tetracantha Lam. is usually used to treat snakebites. The present study aims to provide a scientific explanation for the use of this plant against snakebite. The extracts of shade dried leaves of A. tetracantha were tested for in vitro inhibitory activity on toxic venom enzymes like phosphomonoesterase, phosphodiesterase, acetylcholinesterase, hyaluronidase etc. from Bungarus caeruleus and Vipera russelli venoms.


Assuntos
Animais , Acetilcolinesterase/análise , Antivenenos/análise , Mordeduras de Serpentes/complicações
3.
Artigo em Inglês | LILACS | ID: lil-724675

RESUMO

Snakebites are considered a neglected tropical disease that affects thousands of people worldwide. Although antivenom is the only treatment available, it is associated with several side effects. As an alternative, plants have been extensively studied in order to obtain an alternative treatment. In folk medicine, Azima tetracantha Lam. is usually used to treat snakebites. The present study aims to provide a scientific explanation for the use of this plant against snakebite. The extracts of shade dried leaves of A. tetracantha were tested for in vitro inhibitory activity on toxic venom enzymes like phosphomonoesterase, phosphodiesterase, acetylcholinesterase, hyaluronidase etc. from Bungarus caeruleus and Vipera russelli venoms.


Assuntos
Animais , Acetilcolinesterase/análise , Antivenenos/análise , Mordeduras de Serpentes/complicações
4.
J. venom. anim. toxins incl. trop. dis ; 16(1): 60-75, 2010. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: lil-542429

RESUMO

Snake venoms are rich in enzymes such as phospholipase A2, proteolytic enzymes, hyaluronidases and phosphodiesterases, which are well characterized. However, L-amino acid oxidase (LAO EC.1.4.3.2) from snake venoms has not been extensively studied. A novel L-amino acid oxidase from Bungarus caeruleus venom was purified to homogeneity using a combination of ion-exchange by DEAE-cellulose chromatography and gel filtration on Sephadex® G-100 column. The purified monomer of LAO showed a molecular mass of 55 ±1 kDa estimated by SDS-PAGE. The specific activity of purified LAO was 6,230 ± 178 U/min/mg, versus 230 ± 3.0 U/min/mg for the whole desiccated venom, suggesting a 27-fold purification with a 25% yield. Optimal pH and temperature for maximum purified enzyme activity were 6.5 and 37ºC, respectively. Platelet aggregation studies show that purified LAO inhibited ADP-induced platelet aggregation dose-dependently at 0.01 to 0.1 µM with 50% inhibitory concentration (IC50) of 0.04 µM, whereas at a 0.08 µM concentration it did not induce appreciable aggregation on normal platelet-rich plasma (PRP). The purified protein catalyzed oxidative deamination of L-amino acids while the most specific substrate was L-leucine. The purified LAO oxidizes only L-forms, but not D-forms of amino acids, to produce H2O2. The enzyme is important for the purification and determination of certain amino acids and for the preparation of α-keto acids.(AU)


Assuntos
Animais , Venenos de Serpentes , Agregação Plaquetária , L-Aminoácido Oxidase , Fosfolipases A2 , Cromatografia em Gel
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