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Parthenium hysterophorus(Asteraceae) is known as one of the most aggressive invasive weeds, causing severe economic, environmental, human and animal health problems in India and around the world. During a series of extensive surveys for natural enemies ofP. hysterophorus, a leaf spot pathogen was isolated from the affected parts of the parthenium following the standard isolation techniques using potato dextrose agar (PDA) and parthenium dextrose agar (PeDA) media. Koch's postulates were performed and found satisfactory for the isolate and proved to be pathogenic to this weed. On the basis of cultural, morphological and molecular characteristics, the pathogen was identified asAlternariasp. PMK2. The growth of the pathogen was studied on eight selected media and it exhibited varying degrees of growth on different media. Phytotoxicity of fungal cultural filtrates was also confirmed on parthenium leaves in laboratory conditions. Due to the virulent nature of the isolated pathogen, it may be selected for further studies to develop mycoherbicide for control of this devastating weed. [ABSTRACT FROM AUTHOR]

The present work has been conducted to evaluate the antimicrobial activity of Terminalia chebula against microorganisms associated with juices. Methanol, ethanol, acetone, and aqueous (hot and cold) extracts from fruits of T. chebula were tested for their antimicrobial activity through agar well diffusion method and minimum inhibitory concentration (MIC)/minimum bactericidal concentration (MBC) values were determined through the macrodilution broth method against Bacillus cereus, Serratia sp. and Rhodotorula mucilaginosa. Their total phenolic content and total tannin content were also evaluated. Organic and cold aqueous extracts displayed activity against all three tested microbes. There were highly positive relationship between antimicrobial activities and phenolic and tannin content of the tested extracts against each microorganism. Methanolic extract was found to be best against all tested microbes with lowest MIC of 0.78 mg/ml and MBC of 1.56 mg/ml and showed better antimicrobial activity than sodium benzoate. Therefore, methanolic extract of T. chebula has a biopreservative potential in fruit juices. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorusL. an exotic, pernicious weed is considered as one of the most troublesome weeds for agricultural sector by virtue of its high ecological amplitude and adaptability. Microbes and their by-products are now proved to be a worthy alternative to toxic chemicals used for weed management.Alternaria macrosporaMKPI was isolated from the parthenium leaves infected with leaf blight and found pathogenic to the weed. The herbicidal potential of cell free culture filtrate ofA. macrosporaMKP1 has been tested against parthenium by employing detached leaf bioassay and seed germination bioassay and a significant damage was exhibited by the cultural filtrate of pathogen to the parthenium leaves and seeds. [ABSTRACT FROM PUBLISHER]

Phytase producing strain of Klebsiella sp. DB-3 FJ711774.1 was isolated from poultry field soil. The bacteria produced extracellular phytase under submerged fermentation (Smf) using orange peel and other agro-residues as nutritive substrates. Among different substrates, orange peel flour and wheat bran (2% w/v) provide a maximal yield of production of phytase i.e., 3.15 and 2.41 U/ml respectively when Smf was carried out by using fermentative media supplemented with 0.2% sucrose, 0.1% NH4H2PO4; inoculated with 1.5% cell suspension 24 h age and then, incubated at 50oC for 72 h. As such, there is no report of phytase production by using orange peel as substrate. The phytate biosynthesis by bacteria cultivation on medium based on orange peel flour was accompanied by the liberation of soluble phosphate without any extra supplementation of metal ions. Based on these results the use agro residues in the form of orange peel flour could be one of the best and cost effective alternatives to the costly pure phytate for industrial production of phytase using selected strain of Klebsiella spp. [ABSTRACT FROM AUTHOR]

Statistical experimental designs were applied for the optimization of phytase production by a bacteria Klebsiella sp. DB3 in orange peel flour. Four factors i.e., orange peel flour, ammonium dihydrogen phosphate, temperature and pH were optimized using central composite design (CCD). The optimum levels of variables that supported maximum enzyme activity were orange peel bran 2.0%, sucrose 2.0% and ammonium dihydrogen phosphate (NH4H2PO4) 0.1% and pH 5.5. The validity of the model in optimized conditions was verified. An overall 5.25-fold enhancement in phytase activity (0.60 to 3.15 U) was attained due to the optimization. [ABSTRACT FROM AUTHOR]