Aarti Thakkar

Role of allelochemicals in plant growth promoting rhizobacteria for biocontrol of phytopathogens

Soil borne fungal diseases pose serious constraints on agro-productivity. Biological control is non-hazardous strategy to control plant pathogens and improve crop productivity. PGPR (plant growth promoting rhizobacteria) have long been used as plant disease control agents. PGPR produced a wide range of secondary compounds that may act as signals--that is, allelochemicals that include metabolites, siderophores, antibiotics, volatile metabolites, enzymes and others. Their mode of action and molecular mechanisms provide a great awareness for their application for crop disease management. The present review highlights the role of PGPR strains, specifically referring to allelochemicals produced and molecular mechanisms. Further research to fine tune combinations of allelochemicals, plant-microbe-pathogen interaction will ultimately lead to better disease control.

ANTIOXIDANT AND CYTOTOXIC ACTIVITY OF CommiphoraMukul(GUGGUL) EXTRACTS AGAINST HeLa CELL-LINE.

ShivangiMathur. Commiphoramukul found in India, Pakistan and Bangladesh. Guggul gum resin has been used to treat various diseases including cancer, atherosclerosis, rheumatism and obesity. The crude extracts obtained from the resin of Commiphoramukul in different solvents like ethyl acetate, methanol, acetone, and hexane were analyzed for phytochemical study. Secondary metabolites steroids, quinines, gum and mucilage, fixed oil and fats were found in all the four different extracts of Commiphoramukul however, oxalate and alkaloids were not found in any extract. Ethyl acetate, methanol, acetone, and hexane extracts from method-1(soxhlet) and method2 (cold) were tested for their ability to scavenge DPPH radical. Ethyl acetate extracts exhibited higher antioxidant activity (45.56%) compared to other solvent extracts. Various concentration of Commiphoramukul plant resin extract were used for MTT assay and highest % inhibition/Cytotoxicity (75.68 %) was found by methanol soxhlet extract having lowest IC50 value (58.5μg/ml).