Efficacy of a novel sequential enzymatic hydrolysis of lignocellulosic biomass and inhibition characteristics of monosugars.

Efficient production of sugar monomers from lignocellulose is often hampered by serious bottle-necks in biomass hydrolysis. The present study reveals that ultra-sonication assisted pretreatment following autoclaving, termed as combined pretreatment, can lead to more efficient delignification of lignocellulosic biomass and an open, deformed polysaccharide matrix, found favorable for subsequent enzymatic hydrolysis, is formed. The pattern of inhibition for the enzymatic hydrolysis reaction on combined-pretreated saw dust is identified. Two main inhibition models (competitive and noncompetitive) are proposed and a better fit of experimental values with the theoretical values for the competitive inhibition model validates the proposition that in the present experiment, glucose inhibits the enzymes competitively. Additionally, accuracy of the inhibitory kinetics based models is estimated over a series of enzyme and substrate concentrations.

Evaluation of in vitro antioxidant, anticancer and in vivo antitumour activity of Termitomyces clypeatus MTCC 5091.

CONTEXT: Termitomyces clypeatus (Lyophyllaceae) is a filamentous edible mushroom, having ethnomedicinal uses. However, information about the antioxidant, anticancer and antitumour properties of this mushroom remains to be elucidated. OBJECTIVE: The study examines the in vitro antioxidant, anticancer and in vivo antitumour activity of T. clypeatus. MATERIALS AND METHODS: Antioxidant activity was evaluated with seven in vitro assays. Cytotoxicity of T. clypeatus was tested against a panel of cancer cells lines including U373MG, MDA-MB-468, HepG2, HL-60, A549, U937, OAW-42 and Y-79 using MTT assay. The antitumour activity of aqueous extract was evaluated against Ehrlich ascites carcinoma (EAC) tumour model in Swiss albino mice. RESULTS: HPLC analysis of aqueous extract revealed the presence of sugar entities. Termitomyces clypeatus showed excellent in vitro antioxidant activity. Termitomyces clypeatus was found cytotoxic against all cancer cells, among which it showed higher activity against U937 (IC50 25 ± 1.02 µg/mL). Treatment of EAC-bearing mice with varied doses of aqueous extract significantly (p < 0.01) reduced tumour volume, viable tumour cell count and improved haemoglobin content, RBC count, mean survival time, tumour inhibition and % increase life span. The enhanced antioxidant status in treated animals was evident from the decline in the levels of lipid peroxidation, increased levels of glutathione, catalase and superoxide dismutase. DISCUSSION: The analyzed data indicate that the aqueous extract of T. clypeatus exhibits significant antitumour activity, which might be due to the antioxidant effects on EAC bearing hosts. CONCLUSION: Termitomyces clypeatus possesses anticancer activity, valuable for application in food and drug products.

Carbon dioxide sequestration from industrial flue gas by Chlorella sorokiniana.

The present study investigated the feasibility of using Chlorella sorokiniana for CO2 sequestration from industrial flue gas. The flue gas emitted from the oil producing industry contains mostly CO2 and H2S (15.6% (v/v) and 120 mg L(-1), respectively) along with nitrogen, methane, and other hydrocarbons. The high concentration of CO2 and H2S had an inhibitory effect on the growth of C. sorokiniana. Some efforts were made for the maximization of the algal biomass production using different techniques such as diluted flue gas, flue gas after passing through the scrubber, flue gas passing through serially connected photobioreactors and two different reactors. The highest reduction in the CO2 content of inlet flue gas was 4.1% (v/v). Some new pigments were observed in the flue gas sequestered biomass. Fatty acid composition in the total lipid was determined to evaluate its suitability for food, feed, and biofuel.

Green pigment from Bacillus cereus M(1)(16) (MTCC 5521): production parameters and antibacterial activity.

A bacterial strain, Bacillus cereus M(1)(16) (MTCC 5521), isolated and identified in our laboratory produces a green pigment when grown in nutrient broth at stationary condition. Optimum fermentation parameters for maximum pigment production are pH 7.0, temperature 30°C, time of incubation 72 h and inoculum volume 1% from 20 h grown cell suspension. Magnesium ion enhances pigment production whereas calcium and zinc ions inhibit the process. The pigment is better extracted from the fermented broth with chloroform in comparison with diethyl ether, ethyl acetate, and butanol. The extracted crude pigment consists of three fractions as revealed from thin layer chromatogram on silica gel GF254 using ethyl acetate and hexane (1:1) solvent system. The major fraction C(3) shows antibacterial activity against different gram positive bacteria. The proposed structure of C(3) is 9-methyl-1,4,5,8-tetra-azaphenanthrene obtained by elemental analysis, GC-MS, and NMR spectra studies.