Concomitant yield optimization of tannase and gallic acid by Bacillus licheniformis KBR6 through submerged fermentation : an industrial approach

The present study is concerned with the evaluation of tannase and gallic acid production effi cacy of Bacillus licheniformis KBR6 under diff erent environmental conditions through submerged fermentation. Results have shown that diff erent environmental conditions and mineral sources have diff erential infl uences on tannase and gallic acid production. Highest tannase and gallic acid yield was observed at incubation period of 18 h and 22 h, respectively. At tannic acid concentration of 15 g/l, maximum cell mass (0.75 g/l), cell yield coeffi cient (0.08 g/g), specifi c growth rate (37.5 mg/g/h), tannase yield (16.3 U/g) and specifi c tannase production rate (0.80 U/g/h) were observed, however, at higher tannic acid concentration a decrease in tannase yield and production rate were observed, but gallic acid production increased with increasing tannic acid concentration. Additional carbohydrate sources like glucose, fructose, and lactose showed positive infl uence on enzyme yield. Among the studied nitrogen sources urea and NH4Cl, and of the phosphate sources KH2PO4 showed favourable eff ects on cell growth and simultaneous enzyme and gallic acid production. Temperature of 35 °C was found to be optimum for tannase and gallic acid production. Of all the studied metal ions Ca2+, Mg2+ and Na+ showed positive eff ect whereas, Co2+, Ag2+, Pb2+, Hg2+ showed inhibitory eff ects

Structure-based assortment of herbal analogues against spike protein to restrict COVID-19 entry through hACE2 receptor : an in-silico approach

On-going global pandemic COVID-19 has spread all over the world and has led to more than 1.97 million deaths till date. Natural compounds may be useful to protecting health in this perilous condition. Mechanism of shuttle entry of SARS-COV-2 virus is by interaction with viral spike protein with human angiotensin-converting enzyme-2 (ACE-2) receptor. To explore potential natural therapeutics, 213 important phytochemi-cals of nine medicinal plants Aconitum heterophyllum, Cassia angustifolia, Cymbopogon flexuosus, Cymbopogon martinii, Nux vomica, Phyllanthus urinaria, Swertia chirayita, Justicia adhatoda, Vetiveria zizanioides were selected for in-silico molecular docking against the spike protein of SARS-COV-2 and compared with recently prescribed drug chloroquine, ramdesivir, lopinavir and hydroxychloroquine. Results revealed that rhamnocitrin of P. urinaria, 1,5-dihydroxy-3,8-dimethoxyxanthone of S. chirayita and laevojunenol of V. zizanioides potentially binds with the receptor binding site of SARS-COV-2 spike glycoprotein and more robustly destabilized the RBD-ACE-2 binding over chloroquine, ramdesivir, lopinavir and hydroxychloroquine. It was also found that laevojunenol, rhamnocitrin, and 1,5-dihydroxy-3,8-dimethoxyxanthone qualified the criteria for drug-likeness as per Lipinski rule. After attachment of the selected phytochemical with the spike protein the affinity of the later towards ACE-2 was minimized and the effect of 1,5-dihydroxy-3,8-dimethoxyxanthone and laevojunenol was superior. Hence, rhamnocitrin of P. urinaria, 1,5-dihydroxy-3,8-dimethoxyxanthone of S. chirayita and laevojunenol of V. zizanioides, are potential therapeutic molecules for SARS-COV-2, which upon binding with spike protein changes the affinity of the spike towards ACE-2 and therefore restrict the entry of the virus into a human cell. Subsequent clinical validation is needed to confirm these phytochemicals as drugs to combat COVID-19

A permissive approach for optimization of L-glutaminase production using wheat bran as supporting substrate and assessment of its cytotoxic potentialities

Microbial L-glutaminase has considered as one of the most important therapeutic enzymes considering its anticancer or antitumor activity. In this study, one L-glutaminase producing potent fungus was isolated from the coastal soil and identified as Fusarium nelsonii KPJ-2. During parametric optimization, it was noted that wheat bran supported maximum L-glutaminase production than other agro-industrial wastes tested. Solid substrate fermentation was mechanized with optimum pH of 4.0, incubation temperature at 25 °C, inoculums concentration of 2.0% (v/v), substrate concentration of 7.0% (w/v) and moisture of the production media suits at 20.0% (w/v). Statistical optimization using Response Surface Methodology (RSM) was improved the L-glutaminase production by 14.5% (68.93 U/gds) than unoptimized state. The SEM-EDX analysis demonstrated the overgrowth of fungus on wheat bran and utilization of its associated minerals. A comparative cytotoxic effect of the partial purified glutaminase was examined on both cancerous HCT cell and normal Vero cell line. The result clearly demonstrated that L-glutaminase from F. nelsonii KPJ-2 is specifically cytotoxic against cancer cell line with IC50 of 203.95µg/ml, but, non-responsive against normal cell. The newly isolated fungal strain can produce a considerable amount of L-glutaminase utilizing very low-cost substrate and the enzyme have therapeutic value for real life application owing to its anticancer effectiveness

Arsenic biosorption by mucilaginous seeds of Hyptis suaveolens (L.) Poit

577-581Hyptis suaveolens seeds could serve as natural immobilized source of agriculturally based polysaccharide. Maximum adsorption capacity (6 gl⁻¹) of the seeds for arsenic adsorption has been found at pH 3.5 - 4.5. Among the tested interfering common metal ions, Ca⁺⁺, Mg⁺⁺ and Cl⁻ decreased adsorption rate about 48%, 54% and 30% respectively, whereas Zn⁺⁺ and Co⁺⁺ ions have no significant effect. Adsorption isotherm studies revealed a better correlation with Langmuir isotherm plot

Study of nutritional and antibacterial potential of some wild edible mushrooms from Gurguripal Ecoforest, West Bengal, India

222-227Mushrooms are important natural resources concerning human health, nutrition and disease prevention. The present study was conducted for the exploitation of wild edible mushrooms of Gurguripal Ecoforest. The analysis of nutrients in Termitomyces heimii, Astraeus hygrometricus, Leucopaxilus sp., Amanita vaginata, Agaricus campestris, Russula delica, Schizophyllum commune, Pleurotus ostreatus and Cantharellus sp. on dry wt basis showed that these mushrooms were rich in proteins (20.4-38.3%) and carbohydrates (33.2-48.4%), while lipid contents were relatively low (0.8-6.2%). The fibre and ash contents ranged 2.0-18.6% and 2.3-14.9%, respectively. Antibacterial properties of mushroom extracts were studied against some human pathogens like Escherichia coli MTCC118, Shigella flexneri MTCC7061, Staphylococcus aureus MTCC96, Streptococcus faecalis MTCC5383, Salmonella typhi MTCC734, Klebsiella pneumoniae MTCC109, Enterobacter aerogenes MTCC111, Vibrio cholerae MTCC3906, Pseudomonas aeruginosa MTCC741 and Bacillus subtilis MTCC441. Acetone extracts of P. ostreatus and T. heimii showed noticeable antibacterial potentialities against S. aureus and K. pneumoniae, respectively. Biosynthesis of nanoparticles using mushroom extracts was performed to increase the effectiveness of antibacterial potentials. Silver nanoparticles were synthesized using extracts of Volvariella volvacea and applied against E. coli and S. flexneri, which showed inhibition zones of 15 and 18 mm respectively. The silver nanoparticles were also characterized through UV-Visible spectroscopy and FTIR analysis

<span style="mso-bidi-font-size:12.0pt" lang="EN-GB">Potentialities of newly isolated <i style="mso-bidi-font-style:normal">Bacillus subtilis</i> and <i style="mso-bidi-font-style:normal">Lactobacillus sp</i> for curd preparation and a comparative study of its physico-chemical parameters with other marketed curds </span>

910-918Two Bacillus sp. were isolated from the local fermented milk and identified on the basis 16S rRNA sequence profile as Bacillus subtilis AKL1 and by biochemical process as Lactobacillus acidophilus AKL2. These isolates were <span style="mso-bidi-font-weight: bold">used as fresh inoculums for curd preparation individually and in combinations. Different physico-chemical and therapeutic properties of the newly prepared curd were examined and compared with marketed local (sweet and sour) and branded (Mother Dairy and Thackar) curds. The total hydrolyzed peptides, free amino acids, lactic acid were significantly higher, whereas, total solid, ash content, syneresis and free reducing sugar were lower in the curd prepared by a mixture of AKL1 and AKL2 (0.5:0.5, v/v). The antioxidant activity against ABTS+, DPPH•, OH• and Fe3+ were also higher in the newly formulated curd. Polyphenols (85.5µg/g), flavonoids (12.5µg/g) and free aromatic amino acids contents were also higher in AKL1+AKL2. All these components prevent excess protein oxidation that was revealed by SDS-PAGE. The curd also exhibited potent antimicrobial activity against some entero-pathogens like <i style="mso-bidi-font-style: normal">Clostridium perfringens, <i style="mso-bidi-font-style: normal">Escherichia coli, <i style="mso-bidi-font-style: normal">Shigella dysentery, Vibrio cholerae <span style="background:white;mso-bidi-font-weight:bold;mso-bidi-font-style: italic" lang="EN-GB">and Staphylococcus<i style="mso-bidi-font-style: normal"> aureus. It can be concluded that the combination of these Lactobacillus sp. will be a fruitful inoculum for the preparation of curd having better health promoting effects. </span