Immobilization of rough morphotype Mycolicibacterium neoaurum R for androstadienedione production.

OBJECTIVES: Enhance the androstadienedione (Androst-1,4-diene-3,17-dione, ADD) production of rough morphotype Mycolicibacterium neoaurum R by repeated-batch fermentation of immobilized cells. RESULTS: M. neoaurum R was a rough colony morphotype variant, obtained from the routine plating of smooth M. neoaurum strain CICC 21097. M. neoaurum R showed rougher cell surface and aggregated in broth. The ADD production of M. neoaurum R was notably lower than that of M. neoaurum CICC 21097 during the free cell fermentation, but the yield gap could be erased after proper cell immobilization. Subsequently, repeated-batch fermentation of immobilized M. neoaurum R was performed to shorten the production cycle and enhance the bio-production efficiency of ADD. Through the optimization of the immobilization carriers and the co-solvents for phytosterols, the ADD productivity of M. neoaurum R immobilized by semi-expanded perlite reached 0.075 g/L/h during the repeated-batch fermentation for 40 days. CONCLUSIONS: The ADD production of the rough-type M. neoaurum R was notably enhanced by the immobilization onto semi-expanded perlite. Moreover, the ADD batch yields of M. neoaurum R immobilized by semi-expanded perlite were maintained at high levels during the repeated-batch fermentation.

Advantage Assessment of Mixed Culture of Chlorella vulgaris and Yarrowia lipolytica for Treatment of Liquid Digestate of Yeast Industry and Cogeneration of Biofuel Feedstock.

The symbiosis potential of microalgae and yeast is inherited with distinct advantages, providing an economical venue for their scale-up application. To assess the advantage of the mixed culture of microalgae Chlorella vulgaris and yeast Yarrowia lipolytica for treatment of liquid digestate of yeast industry (YILD) and cogeneration of biofuel feedstock, the cell growth characteristic, the nutrient removal efficiency, the energy storage potential of the mono, and mixed culture were investigated. The results indicated that the biomass concentration of the mixed culture (1.39-1.56 g/L of 5 times dilution group and 1.23-1.53 g/L of 10 times dilution group) was higher than those of mono cultures. The NH3-N and SO42- removal rates of the mixed culture were superior to mono cultures. Besides the higher lipid yield (0.073-0.154 g/L of 5 times dilution group and 0.112-0.183 g/L of 10 times dilution group), the higher yield of higher heating value (20.06-29.76 kJ/L of 5 times dilution group and 21.83-29.85 kJ/L of 10 times dilution group) was also obtained in the mixed culture. This study provides feasibility for remediation of YILD and cogeneration of biofuel feedstock using the mixed culture of microalgae and yeast.

Antinociceptive and anti-hyperglycemic activity of methanol leaf extract of Cyperus scariosus.

The objective of the present study was to investigate the antinociceptive and anti-hyperglycemic activity of methanolic leaf extract of Cyperus scariosus. Antinociceptive activity was determined using a model of acetic acid-induced gastric pain in mice and anti-hyperglycemic activity through glucose tolerance test using glucose loaded mice. In writhing assays induced by acetic acid, the methanolic leaf extract showed dose dependent significant pain inhibition compared to control. The maximum writhing inhibition (46.62%) was found at a dose of 200 mg/kg body weight which was less than that of the positive control, aspirin (56.74%), when used at the same dose. Anti-hyperglycemic activity of the extract was also found to be significant in mice loaded with glucose at doses of 200 and 400 mg/kg body weight. Maximum tolerance (42.86%) was showed at 400 mg extract/kg body weight, which compared favorably with that of glibenclamide at 10 mg/kg body weight (57.62%). In summary, the methanol extract of C. scariosus leaves has had beneficial effects as a pain reliever and also in reducing the elevated blood glucose level of hyperglycemic mice.