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Aflatoxins are toxic metabolites produced mainly by Aspergillus flavus and Aspergillus parasiticus. Aflatoxin B1 (AFB1) is a potent carcinogen, teratogen and mutagen. 660 pre-and post-harvest maize samples were collected from major maize growing areas in Tamil Nadu, India. A flatoxin contamination was observed in 40.22% of the samples tested of which, 22.97% of pre-harvest and 53.93% post-harvest maize samples were found to be infected with AFB1 and 12.05% of the total samples exceeded WHO permissible limit of 20 μg/kg. AFB1 contamination ranged from 0 to 149.32 µg/kg. 28 A. flavus isolates were isolated and grouped into three sets based on aflatoxin producing potential viz., highly aflatoxin producing isolates, medium producing isolates and no aflatoxin producer or traces of aflatoxin producing isolates. The genetic coefficient matrix analysis using random amplified polymorphic DNA (RAPD) with ten random primers revealed minimum and maximum percent similarities among the tested A. flavus strains ranging from 35 to 89%. Cluster analysis separated the three sets of isolates into two groups (groups I and II) with each two subgroup confirming the genetic diversity among the A. flavus isolates from maize.

Induction motors have gained a renewed interest due to this new shift from conventional power sources to electric power. These motors are known for their high commencing torque, adequate speed control and reasonable overload capacity. However, induction motors have an innate thermal issue wherein their lifespan and performance are strongly temperature dependent. Hence, it is highly essential to focus on the thermal management aspect of these motors to ensure reliability and enhance performance. Thus, the major purpose of the paper is to comprehensively review various approaches and methods for thermal analysis, including finite element analysis, lumped parameter thermal network and computational fluid dynamics tools. Moreover, it also presents various cooling strategies commonly adopted in induction motors. Furthermore, this study also suggests an integrated approach with two or more cooling strategies to be the need of the hour. These will combine the benefits of the individual system while helping to counter their drawbacks. This study will help to serve members of the scientific community, manufacturers or motors users who are interested in the thermal management of induction motors.

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Induction of phenolics, peroxidase (PO), polyphenol oxidase (PPO), chitinase and thaumatin-like proteins (TLP) in leaves of chilli (Capsicum annuum L.) in response to foliar application with a biocontrol agent Burkholderia sp. strain TNAU-1 was studied. Chilli plants, when sprayed with Burkholderia sp. strain TNAU-1 showed increase in phenolic content one day after application and the maximum accumulation was observed seven days after treatment. Three new peroxidase isozymes (PO-1, PO-2 and PO-3) were induced in chilli leaves upon treatment with Burkholderia sp. strain TNAU-1. The activity of all the peroxidases was at the maximum level three days after treatment and subsequently decreased. Protein extracts obtained from Burkholderia sp. strain TNAU-1 treated plants exhibited a major polyphenol oxidase (PPO-1) one day after treatment. The activity of PPO-1 subsequently decreased, but continuously present throughout the experimental period of 15 days. Western blot analysis of protein extracts from Burkholderia sp. strain TNAU-1 treated chilli leaves revealed that two TLPs with sizes of 23 and 25 kDa and a chitinase with an apparent molecular weight of 28 kDa were induced three days after treatment

Rich source of biota includes several white rot fungi, were reported in Western Ghats regions of Tamil Nadu, India. The effective identification of white rot fungi and their lignocellulolytic enzymes play a crucial role for degradation of agricultural and industrial wastes to maintain su sta ina ble ecosystem. T hus, the present study was conducted to assess the secretion of lignocellulolytic enzymes of diverse white rot fungi, collected from Western Ghats regions of Tamil Nadu, comprising of Kotagiri and Ooty of the Nilgiri district, Siruvani and Anaikati of Coimbatore district. A total of 16 white rot fungi belonging to 6 genera, viz., Pleurotus spp., Lentinus spp., Ganoderma spp., Trametes spp., Pycnoporus spp. and Schizophyllum spp. were collected and identified through morphological and molecular methods. The activity of cellulase enzyme was prominently visible in Pleurotus pulmonarius, P. sajar-caju, Pycnoporus sanguineus, P. ostreatus, Ganoderma gibbosum and Schizophyllum commune and hemicellulolytic activity was maximum in Trametes ijubarskii, Lentinus crinitus, P. sanguineus and G. gibbosum . The quantitative and qualitative screening for major lignolytic enzymes, viz., laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP) revealed significant levels of Lac secretion when compared to LiP and MnP by P. pulmonarius, P. sajar-caju and Schizophyllum commune. The syringaldazine well test further confirmed the secretion of laccase as major enzyme followed by LiP and MnP. Also the Lac and LiP activity was maximum at pH of 4.5 and MnP activity at pH of 5.0 by P. pulmonarius, P. sajar caju and S. commune. Temperature of 30°C induced maximum secretion of Lac, LiP and MnP by these three fungi. A significant level of Lac was observed on 4 th day after inoculation while LiP and MnP was maximum on 7 th and 8 th day for P. pulmonarius and P. sajar-caju. Whereas, S. commune secreted significant levels of Lac on 10 th to 11 th da y, while LiP and MnP on 6 th and 7 th da y. This study paves the way for u se of P. pulmonarius, P. sajar-caju and S. commune for biodegradation and bioconversion of agrowastes.

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