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This study presents the contents of α-methylenecyclopropylglycine, a potentially toxic amino acid, in the peel, pulp and seed fractions of two well-known litchi varieties, namely Shahi and China, over a span of three harvest-seasons. For analysing α-methylenecyclopropylglycine, an LC-MS/MS-based method was validated. The method-accuracies fell within 75–110 % (RSD, <15 %) at 0.1 mg/kg (LOQ) and higher levels. A comparative evaluation of the results in peel, pulp and seed at 30 days before harvest (DBH), 15-DBH, and edible-ripe stage revealed that α-methylenecyclopropylglycine content increased as the litchi seeds grew towards maturity, regardless of the cultivar. In arils, at maturity, the concentration of α-methylenecyclopropylglycine ranged from not-detected to 11.7 μg/g dry weight. The Shahi cultivar showed slightly higher α-methylenecyclopropylglycine content in comparison to China litchi. This paper presents the first known analysis of combined seasonal data on different fruit components at various growth stages for the two chosen litchi cultivars grown in India. • An LC-MS/MS method optimised for estimation of α-methylenecyclopropylglycine in litchi • MCPG was quantified in peel, seed and aril of China and Shahi litchi at 3 growth stages • MCPG in litchi aril ranged between 0 and 11.7 μg/g DW • Shahi litchi showed slightly higher MCPG content over China cultivar • Ripe arils showed higher MCPG over unripe in Shahi cultivar [ABSTRACT FROM AUTHOR]

Fusarium delphinoides M1, F. brachygibbosum M2, F. pseudonygamai M10, M12_1 and Fusarium species novo M12_2 have been reported as mycoparasites of Plasmopara viticola, a causal agent of downy mildew disease of grapes. This study focused on screening of biocontrol potential of secondary metabolites produced by Fusarium strains using UHPLC-QTOF-MS coupled with UNIFI software. Furthermore, multivariate analysis was performed to analyze discriminant metabolites. The thirty-nine metabolites were identified based on their precursor, fragments ions matching with fungal secondary metabolite database. Among the metabolites, the identity of fusaric acid was the most common and dominant metabolite in extract of five strains. Leaf disc bioassay showed that extract of these strains inhibited >80% sporangia production in P. viticola and IC50of fusaric acid was <0.61 µG/mL against P. viticola. Fusarium strains can be further explored to commercial production of fusaric acid to facilitate management of grapevine downy mildew disease. [ABSTRACT FROM AUTHOR]

The present work was undertaken with an objective to study the effect of culture filtrates and secondary metabolites of three Streptomyces spp. from black pepper rhizosphere having promising biocontrol and growth promoting traits on different developmental stages of pathogens like Phytophthora capsici and Sclerotium rolfsii. The study also focuses on identification of compounds responsible for the antimicrobial and growth promotive activity. Crude culture filtrate of IISRBPAct1 and IISRBPAct25 were found inhibitory to mycelial growth of P. capsici. Diluted culture filtrate of IISRBPAct1 (2%) and IISRBPAct25 (5%) were found inhibitory to the sporangia formation. Crude culture filtrate of IISRBPAct1 can completely inhibit the zoospore germination while it was inhibited to 98.6% and 87% by 10% diluted extracts of IISRBPAct1 and IISRBPAct25 respectively. IISRBPAct1 showed 51.27% inhibition of mycelial growth of S. rolfsii, while IISRBPAct25 and IISRBPAct42 showed 57.63% and 26.90% inhibition respectively. IISRBPAct1 is highly inhibitory to sclerotial formation even at 1% concentration. The secondary metabolites of the three isolates were extracted in three solvent systems and their activity profile was detected and characterized by HPTLC. High resolution UPLC- (ESI)-QToF-MS analysis of the extracts revealed the presence of a vast array of antifungal compounds that supports the antimicrobial activity of culture filtrate and metabolites of the isolates. [ABSTRACT FROM AUTHOR]

This paper reports a sensitive and cost effective method of analysis for aflatoxins B1, B2, G1 and G2. The sample preparation method was primarily optimised in peanuts, followed by its validation in a range of peanut-processed products and cereal (rice, corn, millets) matrices. Peanut slurry [12.5 g peanut + 12.5 mL water] was extracted with methanol: water (8:2, 100 mL), cleaned through an immunoaffinity column and thereafter measured directly by ultra-performance liquid chromatography-fluorescence (UPLC-FLD) detection, within a chromatographic runtime of 5 minutes. The use of a large volume flow cell in the FLD nullified the requirement of any post-column derivatisation and provided the lowest ever reported limits of quantification of 0.025 for B1 and G1 and 0.01 μg/kg for B2 and G2. The single laboratory validation of the method provided acceptable selectivity, linearity, recovery and precision for reliable quantifications in all the test matrices as well as demonstrated compliance with the EC 401/2006 guidelines for analytical quality control of aflatoxins in foodstuffs. [ABSTRACT FROM PUBLISHER]