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1.
Pak J Pharm Sci ; 32(1(Special)): 445-452, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30852483

RESUMO

Five Lactobacillus strains isolated from vegetable and dairy products showed 99% similarity with Lactobacillus plantarum 1(Lp-1) using API -CHL 50 kit. Most of them proved to be sensitive to bacterial cell-wall inhibitors i.e. penicillin, ampicillin, amoxicillin and methicillin as studied by disc-diffusion method. These strains manifested profound tolerance to acidic-stress where Lp86 and Lp36 exhibited a good survival pattern at pH-2 for 4 hr retaining a survival count of 85% and 50%, respectively. A high survival of 85.7% was witnessed in Lp86 in presence of protease while Lp36 maintained 94.55% and 92.65% of population under the influence of enzyme pancreatin and pepsin. All the strains displayed marked tolerance against trypsin as the count did not drop below 77%. Absorbance and growth in terms of cfu/ml for bile-tolerance was examined for concentrations reflecting those in the GIT of humans, all the Lp-1 strains when grown with 1% bile showed a drop in the viable count by 1 log cycle i.e. from 1010 to 109cfu/ml. Fulfilling the above mentioned criteria these probiotic candidates displayed their capacity to reach the colon as viable metabolically active cells after successfully surviving under conditions similar to the gastrointestinal tract of humans. Upon examining the viability and stability of these probiotic candidates in most common foods serving as vehicle for probiotic delivery to the intestine, it was noticed that all the isolates tested sustained a probiotic approved number of 107 cfu/ml for effective function as recommended by WHO, after a maximum storage for one month. Hence, it could be justified that the selected probiotic candidates possess prominent probiotic potential. Therefore, L. plantarum 1 strains could prove to be an efficient probiotic after further in vivo studies to explore its safety in human subjects.


Assuntos
Aderência Bacteriana , Lactobacillus plantarum/crescimento & desenvolvimento , Viabilidade Microbiana , Probióticos , Ácidos e Sais Biliares/química , Microbiologia de Alimentos , Suco Gástrico/química , Trato Gastrointestinal/microbiologia , Humanos , Técnicas In Vitro
2.
Pak J Pharm Sci ; 32(2 (Supplementary)): 889-894, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31103988

RESUMO

Amylases are enzymes that catalyze the hydrolysis of starch into highly valuable products of economic significance. Amylases are used extensively in various industrial sectors. Microbial sources particularly Bacillus species are well known for the cost effective commercial production of amylase enzyme. Present study focuses on the enhancement of amylase enzyme production from an indigenously isolated Bacillus cereus AS2 strain via one variable at a time (OVAT) optimization of different physical and chemical factors. Purposely, eight parameters possibly affecting the amylase production including temperature, pH, incubation time, inoculum size, substrate concentration, metal ions, carbon and nitrogen sources were investigated. According to the results, amylase production was significantly boosted at maximum when the Bacillus cereus AS2 was grown at 45°C on pH 7.0 for 72 hours in the medium supplemented with 4% starch and 0.5% glycine. Among the different metal ions tested, CaCl2 (0.05%) was found significant to accelerate extracellular amylase production.


Assuntos
Amilases/biossíntese , Bacillus cereus/química , Bacillus cereus/metabolismo , Meios de Cultura/química , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Carbono/metabolismo , Glicina/química , Concentração de Íons de Hidrogênio , Metais , Microbiologia do Solo , Amido , Temperatura
3.
Pak J Pharm Sci ; 31(6): 2333-2340, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30473501

RESUMO

Cellulases are the third largest single industrial bio-robots. These enzymes are employed in industries like pharmaceutical, textile, food processing, paper recycling and detergent manufacturing. In order to produce broadly diversified cellulases, microbes (both bacteria and fungi) have been exploited. Different ecological niches have already been explored for the isolation of cellulolytic microbes. However, there have been no remarkable reports viz a viz to the hot oven ash (for cellulolytic bacterial flora). In this regard, a Bacillus strainTLW-3 was isolated and selected for CMCase production and optimization. The strain was identified as B. licheniformis TLW-3 through 16S rDNA sequencing that was submitted to Gen Bank with accession numberKY440432. The isolate growth and CMCase production conditions were optimized to get the maximum CMCase yield. The highest growth and maximum CMCase production by B. licheniformis TLW-3 were recorded at pH 7 and 50ºC, after the incubation period of 72 (hour) at 150rpm. Studies on the various nitrogen and carbon sources on CMCase production showed that the medium having 1% peptone, 0.5% yeast extract and 1% CMC can significantly enhance the enzymatic yield as compared to other (studied) sources. EDTA, Tween-20 and Tween-80 acted as inhibitors for the enzyme production. The present study holds the conviction that the (reported) organism could directly be applied to produce industrial thermophilic CMCase.


Assuntos
Bacillus licheniformis/enzimologia , Proteínas de Bactérias/biossíntese , Celulase/biossíntese , Microbiologia Industrial , Bacillus licheniformis/classificação , Bacillus licheniformis/genética , Bacillus licheniformis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Celulase/genética , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Ribotipagem , Especificidade por Substrato , Temperatura , Fatores de Tempo
4.
Pak J Pharm Sci ; 28(6): 2035-40, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26639497

RESUMO

Extreme environments merit special attention and significance because of the possible existence of thermophilic microorganisms in such ecological niches. Keeping this in mind indigenous stove ash samples were explored for extremophilic bacteria in term of their biodiversity. Accordingly, this study reports 37 bacterial isolates from the local wood run oven (Tandoor) ash samples. All the isolated strains belong to genus Bacillus on the bases of morpho-cultural and biochemical considerations. The average temperature tolerance profile was >45°C thereby, indicating towards the thermophilic nature of the isolated strains. The Bacillus isolates were screened for 10 different hydrolytic enzymes (cellulase, xylanase, amylase, pectinase, caseinase, keratinase, lipase, esterase, dextranase and ß-galactosidase) by plate screening method using the medium incorporated with specific substrate(s). It was found that keratinase was produced by all the isolates while, 36 (97.2%) isolates showed caseinase and esterase production. Amylase was produced by 35(94.6%) isolates and 34 (91.8%) isolates were able to degrade Tween-80 and xylan as substrate for lipase and xylanase respectively. The enzyme, ß-galactosidase was produced by 31 (89.1%) of the isolates. Cellulase and dextranase were produced by 26 (70.2%) and 22 (59.4%) isolates respectively. None of the isolates could (under the existing conditions) produce pectin-hydrolyzing enzyme. According to the Tukey's post hoc test, significant difference was found between the mean enzyme index of all the (screened) enzymes. Thus, the isolated bacterial strains with diverse hydrolytic potential may be of great value and relevance for the existing (national) industrial setups.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/metabolismo , Ecossistema , Enzimas/metabolismo , Incêndios , Temperatura Alta , Microbiologia Industrial , Madeira/microbiologia , Bacillus/classificação , Bacillus/isolamento & purificação , Catálise , Estabilidade Enzimática , Hidrólise
5.
Sci Rep ; 13(1): 11991, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491583

RESUMO

Starch is added to the fabric surface to secure weaving process. During finishing these sized particles are removed from the fabric and prepared it for printing and dyeing. Chemicals de-sizing agents damage fabric surfaces and reduce the quality of the product. An alternative to these conventional desizing agents is the use of biological molecules i.e. enzymes. The current study compares traditional de-sizing to bio-based de-sizing methods, as well as the optimization of fabric desizing settings using crude amylase. Amylase-producing Bacillus cereus AS2 was isolated from indigenous soil samples. The maximal fermentative de-sizing capability was discovered at 72 h, with no fabric surface degradation. Chemical desizing showed that the fabric lost all sizing agents to TEGEWA scale 9 within 1 h in presence of 5N HCl. Optimal studies for desizing showed that 1000 IU/ml of amylase resulted in maximum de-sizing within 15 h at 60 °C and 0.5% Triton-X. Water absorbance and weight loss, both parameters were used to check the desizing efficacy and it was found that de-sizing to same scale was occurred in the case of enzyme as well as commercially desized fabric. Enzyme desized cloth was found to be free of any starch particles in SEM micrographs, identical to industrially de-sized fabric, ensuring bioprocess efficacy.


Assuntos
Amilases , Bacillus cereus , Bacillus cereus/metabolismo , Têxteis , Amido/metabolismo
6.
Front Med (Lausanne) ; 10: 1283302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38076266

RESUMO

Introduction: Aging leads to significant structural and functional changes in blood vessels, which disrupt their normal function and impact cardiovascular health. Current research is actively exploring the NRF2 antioxidative pathway, recognizing its role in protecting cells by preserving their antioxidant defenses against damage. However, there has been limited exploration into the role of the NRF2 pathway in vascular aging. The primary objective of this study was to determine whether age-related changes in the aorta are associated with variations in the baseline levels of antioxidant enzymes, with a particular emphasis on how the NRF2 pathway operates in the aortic wall. Methods: A group of healthy aging female SD rats was compared with their younger counterparts. Various assessments were conducted, including measuring blood pressure, analyzing serum lipid profiles, examining aortic tissue, and assessing the expression of antioxidant enzymes. Results: The results revealed significant differences in both blood pressure and serum lipid levels between the aged and younger rats. The examination of the aorta in older rats showed structural alterations, increased apoptosis, and the accumulation of fatty deposits. In the older rats, levels of SOD-1 (superoxide dismutase) and GSS (glutathione synthetase) were lower, whereas NRF2, KEAP-1 (Kelch-like ECH-associated protein 1), and HO-1 (Heme oxygenase 1) were higher. Discussion: This study advances our understanding of how aging affects the antioxidant system in blood vessels, particularly in relation to the regulation of the NRF2/HO-1 pathway in the aorta. These findings suggest that targeting the NRF2/HO-1 pathway could present anovel therapeutic approach for addressing age-related vascular issues.

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