At the face of emergence of multiple antibiotic resistant strains, herbal antimicrobials are looked as the future drugs for therapeutics, and also as food preservative. This study was undertaken to understand the antimicrobial activity of some selected herbal preparations on bacteria of food origin. In the study 464 (254 from foods of vegetable origin, 134 from foods of animal origin, 14 from food handlers, 62 reference) strains belonging to more than 104 species of 33 genera of Gram negative (194) bacteria (GNB) and Gram positive (270) bacteria (GPB) were tested for their sensitivity to methanolic extract of Eupatorium odoratum (EOME), methanolic extract of Ageratum conyzoides (ACME), methanolic extract of Zanthoxylum rhetsa seed coat (ZRME), lemon grass (Cymbopogon citratus) oil (LGO), sandalwood (Santalum album) oil (SWO), patchouli (Pogostemon cablin) oil (PO) and agarwood (Aquilaria crassna) oil (AO) through disc diffusion method. Besides, minimum inhibitory concentration (MIC) of different herbal preparations was determined for test strains using agar-well dilution method. Sandalwood oil inhibited maximum number of strains (50.5%) followed by LGO (45.9%), EOME (43.8%), ACME (40.4%), PO (38%), ZEME (19.6%) and AO (17.5%). Enterobacteriaceae strains in general showed more resistance to herbal antimicrobials than strains of any other family. The MIC for different herbal preparations varied for different strains from 1 µg mL-1 to > 16.384 mg mL-1. The study indicated that herbal antimicrobials being edible and acceptable since ages can be an option for use in foods to control spoilage and choice may depend on type of microbe causing the problem in the specific food unit.

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