Bergenia ciliata Sternb., commonly known as Paashaanbhed, is a well known herb of Sikkim Himalaya with various pharmaceutical properties. However, scientific exploration of B. ciliata, growing in the Sikkim Himalaya, for phytochemicals and pharmacological properties is in infancy. With this view, the present study was undertaken to investigate B. ciliata leaf extracts for antioxidant, antimicrobial activity and bioactive compounds. Three solvents viz., methanol, ethyl acetate and hexane were used for extraction and the respective leaf extracts were analyzed for total phenolic and flavonoid contents along with the antioxidant and antimicrobial activities. Amongst the tested solvents, methanol was found to be the best solvent for extraction with highest total phenolic contents and the lowest IC50 values for the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Methanol extract also exhibited effective antimicrobial activity, particularly against bacteria and actinomycetes. Further, high performance liquid chromatography (HPLC) analysis revealed that methanolic extract contains the highest amount of all the three analyzed bioactive compounds viz. bergenin, catechin and gallic acid. The current study suggests that the methanol extract of B. ciliata is a potential source of natural antioxidant and antimicrobial compounds that can be used in food and drug industries.

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The present study was designed to screen 20 fungi for their potential to degrade the chlorinated organic pesticides endosulfan and chlorpyrifos. Fungi were first screened for their tolerance to various concentrations of target pesticides using soil extract agar and subsequent degradation studies were performed in soil extract broth containing 25 mg/L of the individual pesticide. Pesticide degradation was evaluated using gas chromatography. Other parameters, such as pH and mycelial weight, were also determined. Based on percent growth inhibition of test fungi and subsequent analysis of EC50 values, the overall results revealed that chlorpyrifos showed significantly more growth inhibition in all tested fungi compared with endosulfan. Trametes hirsuta showed complete degradation of both α‐ and β‐endosulfan isomers and Cladosporium cladosporioides displayed maximum degradation of chlorpyrifos. All test fungi degraded endosulfan more efficiently than chlorpyrifos, except Phanerochaete chrysosporium, Trichoderma harzianum, and Trichoderma virens which showed higher degradation of chlorpyrifos than endosulfan. It was also found that all tested fungi degraded α‐endosulfan more efficiently than β‐endosulfan. Endosulfan sulfate was found to be the major degradation product with all tested fungi. Fungi which showed more endosulfan degradation also produced more endosulfan sulfate. However, less endosulfan sulfate was detected with T. hirsuta and Trametes versicolor, although they degraded endosulfan more efficiently.

The reactions of monolayers of cellulose, spread from Cadoxen solvent, with a variety of solutes in the aqueous phase have been studied by measurement of film expansion, compressibility, and viscosity, with a view to elucidating the mechanism of dye adsorption by cellulose. Refractometry measurements of bulk solutions have also been used.Phenol has no effect on the film, but urea expands it. Cationic dyes, e.g., Methylene Blue, associate weakly with the monolayer to give a mixed film of high compressibility. Anionic dyes slightly expand the film, without change in its compressibility or viscosity. This expansion is almost identical for monoazo-dyes with little affinity for cellulose in bulk, as it is for bisazo-dyes, with similar molecular width, but of high cellulose affinity. A direct dye with a wider molecule causes greater film expansion, approximately proportionate to this increased width. This evidence suggests face to-face association of cellulose and anionic dye molecules parallel to the cellulose chain.Refractometry, but not the other tests, reveals weak complexing, probably of an acid-base type, between cellulose and amino-groups in dyes. This is the only dye-cellulose force identified.Dye adsorption by cellulose in bulk is explained by this and other recent work, e.g., the known tendency of the dye to escape from aqueous solution, causes it to concentrate a t the cellulose-water interface. There it becomes aligned parallel to the cellulose chains possibly by hydrophobic bonding with glucosidic >CH groups. It then associates to form multilayers or three-dimensional aggregates. This process occurs more readily with long narrow planar molecules and is assisted in technical practice by the presence of excess of neutral inorganic salt in the dyeba t h.