Surjit Sen

Pseudomonas aeruginosa WS-1 for biological control of leaf blight disease of Withania somnifera

Withania somnifera (L.) Dunal, also known Indian ginseng is one of the most widespread tranquillizers tranquillisers used for the treatment of nervous disorders, intestinal infection, leprosy, and cancer; it also suffers a leaf blight disease caused by the fungus Alternaria dianthicola in various districts of South Bengal, India: Pseudomonas aeruginosa strain WS-1 isolated from the rhizosphere, showed both in vitro and in vivo antagonistic activity against the pathogen. The antifungal activity of the isolate has been found to be linked to theproduction of a siderophore, volatile substances (hydrocyanic acid), proteases and chitinases. Foliar application of a talc talc-based formulation of P. aeruginosa strain WS-1 to field grown W. somnifera reduced disease severity by 80% compared to non-treated control.

First report of leaf blight disease of Gloriosa superba L. caused by Alternaria alternata (Fr.) Keissler in India

Leaf blight disease was found on Gloriosa superba L. (Liliaceae), an endangered, herbaceous, perennial, climbing lily that produces colchicine, in West Bengal, India in 2004. Small brownish spots on leaves developed into concentric rings, which eventually darkened and coalesced to blight the entire leaf. The causal fungus was morphologically identified as Alternaria alternata (Fr.) Keissler. This is the first record of A. alternata on G. superba.

Plants of Genus Mentha: From Farm to Food Factory

Genus Mentha, a member of Lamiaceae family, encompasses a series of species used on an industrial scale and with a well-described and developed culture process. Extracts of this genus are traditionally used as foods and are highly valued due to the presence of significant amounts of antioxidant phenolic compounds. Many essential oil chemotypes show distinct aromatic flavor conferred by different terpene proportions. Mint extracts and their derived essential oils exert notable effects against a broad spectrum of bacteria, fungi or yeasts, tested both in vitro or in various food matrices. Their chemical compositions are well-known, which suggest and even prompt their safe use. In this review, genus Mentha plant cultivation, phytochemical analysis and even antimicrobial activity are carefully described. Also, in consideration of its natural origin, antioxidant and antimicrobial properties, a special emphasis was given to mint-derived products as an interesting alternative to artificial preservatives towards establishing a wide range of applications for shelf-life extension of food ingredients and even foodstuffs. Mentha cultivation techniques markedly influence its phytochemical composition. Both extracts and essential oils display a broad spectrum of activity, closely related to its phytochemical composition. Therefore, industrial implementation of genus Mentha depends on its efficacy, safety and neutral taste.