Browsing by Subject "antioxidant"

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    Antioxidant and antimicrobial activities of a common liverwort from Darjeeling Himalaya
    (University of North Bengal, 2009-03) De, Rajib; Saha, Jayati; Sarkar, Prabir K
    The study was concerned with an examination of antioxidant and antimicrobial activities of methanolic extract of Marchantia convoluta (Merch.) L.. collected from Darjeeling Himalaya. The antioxidant activities were evaluated by means of five in vitro methods, viz. free radical-scavenging activity, Fe3+ -reducing power, metal-chelating ability, trolox equivalent antioxidant capacity (TEAC) and activity in hydroxyl radical-scavenging system. The total phenol content was 1.1 mg gallic acid equivalents g-1 dried thallus. After 30 min of reaction, the 100 mg lyophilized extract possessed 6.7 % free radical-scavenging activity. The same amount of extract exhibited 13.4 % 168.2 % metal-chelating and hydroxyl radical scavenging activities, respectively. The reducing activity was found to be 28.5 mg ascorbic acid equivalents g-1 dried thallus. Total antioxidant activity was 0.18 μg TEAC g-1 dried thallus. The antimicrobial activity was evaluated by testing the methanolic extract of the samples against five microorganisms including two Gram positive bacteria (Staphylococcus aureus and Bacillus cereus), two Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae) and one yeast (Candida albicans by disc-diffusion assay. M. convoluta thallus extract was more or less inhibitory against all of the test bacteria, however did not possess any antifungal property. S. aureus was found to be most sensitive target organism.
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    A comparative study of silkworm (Bombyx mori L.) rearing under different sources of peptides isolated from Dudhiya and S1 mulberry leaves
    (University of North Bengal, 2015-03) Jha, Suchisree; Bhattacharyya, Phalguni; Ghosh, Amitava; Mandal, Palash
    Silkworm is a domestic monophagous insect, produces only natural animal the fibre. Growth of silkworm larvae depends on nutritional components of mulberry leaves. In present study one attempt was made to investigate the role of low molecular weight (0.5-3 kDa) mulberry peptides on silkworm rearing. For peptide extraction, two different types of mulberry leaves were chosen, one from S1 which was preferred by larvae for feeding, another is a germplasm named Dudhia, refused by larvae. Peptides isolated from young S1 leaves showed higher larval growth followed by peptides isolated from mature and senescence leaves. High ERR% along with enhanced weight of single cocoon and single shell was observed in silkworm fed with S1 peptide treated mulberry leaves as compared with the same by Dudhia peptides. Elevated antioxidant activities were exhibited by S1 peptides than Dudhia at all maturity stages (young, mature and senescence). Significant correlation was obtained between antioxidant activities of S1 peptides and economical attributes of silkworm rearing such as ERR %, weight of single cocoon, weight of single shell etc. From our observation it might be stated that the farmers would have been benefited if they could use mulberry leaves treated with antioxidant enriched peptides as a food for silkworm rearing.
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    Evaluation of antioxidant activities of some locally available edible plants of Darjeeling Himalaya
    (University of North Bengal, 2014-02) Ghosal, Mitali; Mandal, Palash
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    ItemOpen Access