Sorghum-based traditional fermented food was screened for potential probiotic lactic acid bacteria. The isolates were identified by biochemical, physiological and genetic methods. Species identification was done by 16s rRNA sequence analysis. The functional probiotic potential of the two Lactobacillus species viz., Lactobacillus plantarum (Lact. plantarum) and Lactobacillus pentosus (Lact. pentosus) was assessed by different standard parameters. The strains were tolerant to pH 2 for 1 h and resistant to methicillin, kanamycin, vancomycin and norfloxacin. Two (Lact. plantarum COORG-3 and Lact. pentosus COORG-8) out of eight isolates recorded the cell surface hydrophobicity to be 59.12 and 64.06%, respectively. All the strains showed tolerance to artificial duodenum juice (pH 2) for 3 h, positive for bile salt hydrolase test and negative for haemolytic test. The neutralized cell-free supernatant of the strains Lact. pentosus COORG-4, Lact. plantarum COORG-1, Lact. plantarum COORG-7, Lact. pentosus COORG-8 and Lact. plantarum COORG-3 showed good antibiofilm activity. Lact. pentosus COORG-8 exhibited 74% activity against Pseudomonas aeruginosa-MTCC 7903 and Lact. plantarum COORG-7 showed 68% inhibition of biofilm against Klebsiella pneumonia MTCC 7407. Three (Lact. plantarum COORG-7, Lact. pentosus COORG-5 and Lact. pentosus COORG 8) out of eight isolates exhibited a good antimicrobial activity against Listeria monocytogenes and five isolates (Lact. pentosus COORG 2, Lact. plantarum COORG 1, Lact. plantarum COORG 4, Lact. pentosus COORG 3 and Lact. plantarum COORG 6) are active against Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Enterobacter aerogenes, Klebsiella pneumonia, Enterococcus faecalis. The study also evaluated the cholesterol lowering property of the Lactobacillus strains using hen egg yolk as the cholesterol source. The cholesterol in hen egg yolk was assimilated by 74.12 and 68.26% by Lact. plantarum COORG 4 and Lact. pentosus COORG 7, respectively. The results of the present study suggest that the Lactobacillus strains isolated and characterized from sorghum-based fermented product may be used as probiotic strains for therapeutic applications.

Antifungal efficacy of on infection, total seedlings mass, root and shoot length, and seed germination in maize, sorghum, and wheat were investigated. Antifungal efficacy of against, , and showed a significant reduction in growth and infection incidence (up to 50%) in all the three treated cereals. However, challenge inoculation of spp. to the three cereals showed 100% infection incidence. Total mass of the maize seedlings increased two fold by treatment; however, only a slight increase was observed in sorghum and wheat seedlings. The highest vigour index recorded in maize was 1321 against crookwellense, 1616.71 against in sorghum, and 1584.8 against in wheat treated with. Highest germination incidence of 64% was in maize, 67% in sorghum, and 56% in wheat treated with .

A total of 198 cereal samples (53 maize, 54 sorghum, 37 paddy and 54 wheat) were collected from 11 districts of Karnataka to understand the percent infection (PI), relative density (RD) and their frequency (Fr) caused by Fusarium spp. All samples were screened by agar plating method using MGA 2.5 agar media and incubated at 25 ± 2 °C for 3–5 days. The study revealed the association of 10 different Fusarium species known trichothecene producers such as Fusarium acuminatum, F. avenaceum, F. crookwellense, F. culmorum, F. equiseti, F. graminearum, F. nivale, F. poae, F. sambucinum and F. sporotrichioides along with non-trichothecene producers like F. anthophilum, F. oxysporaum, F. proliferatum, F. semitectum, F. solani, and F. verticillioides. All the ten isolated potential trichothecene producing Fusarium species were analyzed for their ability to produce trichothecenes by using thin layer chromatography method. The highest infection of Fusarium spp. in maize was by F. verticillioides with PI of (2.95 %), with RD of (15.16 %) and highest Fr was by F. graminearum (79.24 %) and the lowest was F. avenasium with PI of (0.13 %). For sorghum maximum PI was by F. verticillioides (3.02 %), with F. graminearum having highest RD (14.39 %) and with F. verticillioides highest Fr. (72.22 %). In paddy highest PI was by F. verticillioides (3.21 %) and the least was by F. avenaceum (0.09 %). Similarly in wheat the highest PI was by F. verticillioides (2.76 %) while lowest was by F. avenaceum (0.10 %). The highest Fr was with F. graminearum (79.62 %) while the lowest was by F. avenaceum (3.70 %) and the highest RD was by F. graminearum (22.04 %) and lowest was by F. solani (0.72 %). The manually identified Fusarium spp. were further confirmed by PCR-based detection using ITS1 and ITS4 primers followed by sequencing of the PCR amplicons. PCR studies confirmed that all the tested fungal isolates belongs to Fusarium spp. with the amplicon size of 600 bp. Sequencing and the blast data from NCBI data base confirmed the sequence similarity of 99 % to the genus Fusarium and accession numbers were obtained. Chemotyping studies showed that the isolated Fusarium species are known to produce different types of trichothecenes. The study revealed the diversity in phytopathogenic Fusarium spp. in major cereal crops growing in different agro-climatic regions of Karnataka, India.

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Aspergillus species are known to cause damage to food crops and are associated with opportunistic infections in humans. In the United States, significant losses have been reported in peanut production due to contamination caused by the Aspergillus species. This study evaluated the antifungal effect and anti-aflatoxin activity of selected plant-based essential oils (EOs) against Aspergillus flavus in contaminated peanuts, Tifguard, runner type variety. All fifteen essential oils, tested by the poisoned food technique, inhibited the growth of A. flavus at concentrations ranging between 125 and 4000 ppm. The most effective oils with total clearance of the A. flavus on agar were clove (500 ppm), thyme (1000 ppm), lemongrass, and cinnamon (2000 ppm) EOs. The gas chromatography-mass spectrometry (GC-MS) analysis of clove EO revealed eugenol (83.25%) as a major bioactive constituent. An electron microscopy study revealed that clove EO at 500 ppm caused noticeable morphological and ultrastructural alterations of the somatic and reproductive structures. Using both the ammonia vapor (AV) and coconut milk agar (CMA) methods, we not only detected the presence of an aflatoxigenic form of A. flavus in our contaminated peanuts, but we also observed that aflatoxin production was inhibited by clove EO at concentrations between 500 and 2000 ppm. In addition, we established a correlation between the concentration of clove EO and AFB1 production by reverse-phase high-performance liquid chromatography (HPLC). We demonstrate in our study that clove oil could be a promising natural fungicide for an effective bio-control, non-toxic bio-preservative, and an eco-friendly alternative to synthetic additives against A. flavus in Georgia peanuts.