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BackgroundAspergillus fumigatus R1 produced xylanase under submerged fermentation which degrades the complex hemicelluloses contained in agricultural substrates. Xylanases have gained considerable attention because of their tremendous applications in industries. The purpose of our study was to purify xylanase and study its biochemical properties. We have predicted the secondary structure of purified xylanase and evaluated its active site residues and substrate binding sites based on the global and local structural similarity.ResultsVarious microorganisms were isolated from Puducherry soil and screened by Congo-red test. The best isolate was identified to be Aspergillus fumigatus R1. The production kinetics showed the highest xylanase production (208 IU/ml) by this organism in 96 h using 1 % rice bran as the only carbon source. The purification of extracellular xylanase was carried out by fractional ammonium sulphate precipitation (30–55 %), followed by extensive dialysis and Bio-Gel P-60 Gel-filtration chromatography. The enzyme was purified 58.10 folds with a specific activity of 38196.22 IU/mg. The biochemical characterization of the pure enzyme was carried out for its optimum pH and temperature (5.0 and 500C), pH and temperature stability, molecular mass (Mr) (24.5 kDa) and pI (6.29). The complete sequence of protein was obtained by mass spectrometry analysis. Apparent Km and Vmax values of the xylanase for birchwood xylan were 11.66 mg/ml and 87.6 μmol min−1 mg−1 respectively.ConclusionPurified xylanase was analyzed by mass-spectrometry which revealed 2 unique peptides. Xylanase under current study showed significant production using agricultural residues and a broad range of pH stability in the alkaline region. Xylanase produced by Aspergillus fumigatus R1 could serve as the enzyme of choice in industries.

The effect of exogenous microbial lipase enzyme on the ripening of Swiss cheese (0, 200, and 800U lipase in 30 L milk) was investigated for the physicochemical, textural and sensory properties, along with its microstructure. The aim of this study was to investigate the application of microbial lipase to accelerate the ripening without affecting its original desirable quality characteristics. The effect of the microbial lipase was studied at different time periods (2, 30, 45, and 60 days) of the Swiss cheese ripening stages. Statistical analysis of the results showed that the physico-chemical parameters of cheese slightly increased during the ripening. Also, at all stages of the ripening hardness of Swiss cheese increased while the brittleness decreased. The number and size of the fat globules were also affected by the addition of the lipases. This study also showed that increase in the lipase amount had no significant change in quality and sensory parameters. Therefore, 200U of lipase was found to be sufficient to reduce the ripening time from 90 to 60 days by maintaining its genuine quality. Thus, this study suggested that the addition of microbial lipase may significantly reduce the cost of the cheese production by lowering the ripening period by 1 month and maintaining the quality of the final product.

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Background Women of reproductive age group have greater predilection to urinary tract infections (UTI). Various risk factors increase the prevalence in women. Emergence of multidrug resistant uropathogens make clinical management of UTI challenging. Here we assess holding of urine as risk factor of UTI in women and reasons for delayed voiding. We also investigate the relationship between frequency of UTIs and overall behavioural features, menstrual hygiene and attitude of women towards their own health issues. Methods A questionnaire based cross-sectional study was performed with 816 hostel residents with written consent. Self-reported data was statistically analysed using SPSS software. Urinalysis and urine culture were done for 50 women by random sampling to obtain the information on leading causative agents of UTI in the study population and their antimicrobial resistance profile. Results The prevalence of UTI among the participants without risk factors was found to be 27.5 (95% CI: 24.4–30.7). Attitude of women towards their own personal health issues and use of public toilets showed a correlation with prevalence of infection. Delay in urination on habitual basis was found to be associated with UTI. Uropathogens isolated by random sampling were resistant to multiple drugs that are generally used to treat UTI. Conclusions Holding urine for long time had proven to be an important risk factor and amongst different reasons of holding urine, holding due to poor sanitary condition of public toilets was the most common. Higher frequency of self-reported UTIs is related to holding of urine, behavioural features and attitude of women.