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A Clostridium strain PXYL1 was isolated from a cold-adapted cattle manure biogas digester at 15 ‡C. It could grow at temperatures as low as 5 ‡C up to 50 ‡C with highest specific growth rate at 20 ‡C and is a psychrotroph. It produced extracellular hydrolytic enzymes namely xylanase, endoglucanase, L-xylosidase, L-glucosidase and filter paper cellulase, all of which had maximal activity at 20 ‡C. The induction of xylanase was highest on birch wood xylan (37 IU{mg protein} 31 ) compared with xylose (1.11 IU{mg protein} 31 ), cellobiose (1.43 IU{mg protein} 31 ) and glucose (no activity). The xylanase was thermolabile with a half-life of 30 min at 40 ‡C and 8 min at 50 ‡C but stable for over 2 h at 20 ‡C. The crude enzyme released reducing sugars (1.25 g l 31 ) from finger millet flour at 20 ‡C, while commercial food-grade xylanases showed no hydrolysis at this temperature. This is the first report of a Clostridium strain growing at 20 ‡C and producing an array of xylanolytic and cellulolytic enzymes, possessing low temperature optima of 20 ‡C, which may facilitate degradation of plant fibre under low-temperature conditions. ß

Aim:  Bioaugumentation of low temperature biogas production was attempted by addition of cold‐adapted Clostridium and a methanogen. Methods and Results:  A psychrotrophic xylanolytic acetogenic strain Clostridium sp. PXYL1 growing optimally at 20°C and pH 5·3 and a Methanosarcina strain, PMET1, growing optimally on acetate and producing methane at 15°C were isolated from a cattle manure digester. Anaerobic conversion of xylose at 15°C with the coculture of the two strains was performed, and batch culture methane production characteristics indicated that methanogenesis occurred via acetate through ‘acetoclastic’ pathway. Stimulation studies were also undertaken to evaluate the effect of exogenous addition of the coculture on biogas yields at 15°C. Addition of 3 ml of PXYL1 at the rate of 12 × 102 CFU ml−1 increased the biogas 1·7‐fold (33 l per kg cowdung) when compared to control (19·3 l per kg cowdung) as well as increased the volatile fatty acid (VFA) levels to 3210 mg l−1 when compared to 1140 mg l−1 in controls. Exogenous of addition of 10 ml PMET1 inoculum at the rate of 6·8 ± 102 CFU ml−1 in addition to PXYL1 served to further improve the biogas yields to 46 l kg−1 as well as significantly brought down the VFA levels to 1350 mg l−1. Conclusions:  Our results suggest that the rate‐limiting methanogenic step at low temperatures could be overcome and that biogas yields improved by manipulating the population of the acetoclastic methanogens. Significance and Impact of the Study:  Stimulation of biomethanation at low temperature by coculture.

Tumour markers correlate strongly with prognosis on tumour burden. Glycoprotein components and lysosomal hydrolases play an important role in carcinogenesis. Hence, this study was launched to evaluate the effect of Kalpaamruthaa (KA), a modified Siddha preparation, on the changes in glycoprotein components, lysosomal enzymes and marker enzymes in control and mammary carcinoma bearing rats. A significant increase in the activities of alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH) and 5 nucleotidase (5 -NT) in plasma, liver and kidney were observed in animals with mammary carcinoma. The activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly reduced in the liver and kidney whereas increased in plasma of cancerous animals. On administration of KA, these changes were reverted back to near normal levels. The increased levels of glycoprotein components (hexose, hexosamine and sialic acid) and in the activities of lysosomal enzymes such as acid phosphatase (ACP), β-D-Glucuronidase, β-D-Galactosidase, N-acetyl-β-D-glucosaminidase and Cathepsin-D (CD) found in mammary carcinoma were also significantly decreased in KA treated animals. In all these studies, simultaneous KA administration proved more efficacious than post KA treatment, thus depicting the effective control of KA against the development of mammary carcinoma.

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