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A series of pyrazole integrated thiazolo[2,3-b]dihydropyrimidinone derivatives were synthesized as dual anti-inflammatory and antimicrobial agents. Among the compounds studied, 3-fluoro-4-methylphenyl analogues (3a, 3e, and 3i) are considered to be promising leads for novel anti-inflammatory agents compared with the standard drug. The superior antimicrobial property of the compounds 3a, 3b, and 3d indicates that 3-(3,4-dichlorophenyl)-1-phenyl-1H-pyrazole substitution is a favourable site for high activity. Molecular docking studies were carried out in order to predict the hypothetical binding mode of these compounds to the COX-2 isoenzyme. The results of the present study suggest that 1,3-diaryl pyrazole substitution on thiazolo[2,3-b]dihydropyrimidinone derivatives might potentially constitute a novel class of anti-inflammatory agents with antimicrobial property and could be an interesting approach for the design of new selective COX-2 inhibitory agents.

Association of Chrysanthemum stunt viroid (CSVd) and Chrysanthemum chlorotic mottle viroid (CChMVd) with the Chrysanthemum plants exhibiting severe stunting, distinct yellow leaf mottling, and chlorosis was detected in the main chrysanthemum-growing regions of India. Sequence analysis of 90 cDNA clones obtained for CSVd and CChMVd, representing the chrysanthemum-growing regions of India, revealed the high degree of sequence variation throughout the genome under natural conditions. Additionally, all the analyzed CChMVd clones revealed the presence of UUUC in the tetraloop, a signature of symptomatic variants in susceptible cultivars. Phylogenetic analysis revealed that Indian CSVd is closely related to European isolates from ornamentals, whereas CChMVd clustered along with the isolates reported from the East Asian countries.

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

Among the 194 Fusarium verticillioides isolates screened from 127 cereal samples, 176 were fumonisin producers and others were non-producers. Representative nine Fusarium verticillioides strains along with one reference standard strain MTCC156 were selected to study their morphological, pathological and mycotoxicological variations by conventional and molecular approaches. Fusarium verticillioides strains FVM86, FVM146, FV200 and FVS3 showed significant pathogenicity and also in pigmentation production but varied in fumonisin production. Fusarium verticillioides strain FVP19 recorded variations in all the assays. Fusarium verticillioides strain FVM42 showed drastic phenotypic variation and it also produced fumonisin. Genetic variation among the strains was independent of geographic area of origin but depended on their ability to produce fumonisin. The strains were independent in their cultural characteristics, pigmentation production, pathogenicity assays, fumonisin production and in their genetic variability without having any correlation.

A facile and convenient synthesis of Mannich bases 5a–f and S-alkylated derivatives 6a–f and 7a–f has been carried out from the key intermediate 5-(5-methyl-1-phenyl-1H-pyrazol-4-yl)-1,3,4-oxadiazole-2(3H)-thione (4). Intermediate 4 was obtained from one-pot reaction of ethyl acetoacetate, phenylhydrazine, and N,N-dimethylformamide dimethyl acetal (DMF-DMA) followed by reaction with hydrazine hydrate and carbon disulfide. The structure of the newly synthesized compounds was established on the basis of elemental analysis, infrared (IR), 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectroscopic data. All synthesized compounds were screened for in vivo antiinflammatory, in vivo analgesic, and in vitro antimicrobial activity. From the activity studies, it was concluded that, among all the derivatives, compounds 5c, 5e, 5f, 6c, 7b, and 7c showed potent antiinflammatory activity, whereas 5b, 5c, 5e, 5f, 6c, 6f, 7b, 7c, and 7e exhibited good analgesic activity. Compounds 6a, 6c, 7b, 7c, and 7d showed maximum activity against the bacterial strains. Efforts were also made to establish structure–activity relationships among the tested compounds.

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.

Plant pathogens like ‘Ca. Liberibacter’, phytoplasma, viruses and viroids cause diseases to almost all economically important plants. A simple and fast sap-mediated polymerase chain reaction (PCR) method for the detection of these pathogens infecting various plant hosts is described in the present study. Sap from selected plants was drawn aseptically on parafilm, from the mid-rib of young leaves. Depending on the type of host plant, sap was diluted to optimal concentration before PCR analysis. ‘Ca. Liberibacter’, Citrus tristeza virus (CTV) and Citrus exocortis viroid (CEVd) infecting citrus, and ‘Ca. Phytoplasma’ infecting pepper and sandal trees were tested by sap-mediated PCR. The reliability of this procedure was evaluated by comparing the findings with previously described protocols. The sap-mediated nucleic acid template preparation for PCR assay is devoid of laborious nucleic acid extraction and expensive chemicals. Hence the present method is rapid, economical and so can be employed for diagnosis of large number of plant samples.

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.

The antifungal activity of essential oils from clove, cedar wood, Cymbopogon species, peppermint, Eucalyptus and neem were tested for their efficacy against nine Fusarium species, namely F. verticillioides, F. proliferatum, F. o x y spo r u m, F. a n -thophilum, F. pallidoroseum, F. sporotrichioides, F. sol ani, F. g ra m i n ea r u m and F. lateritium, isolated from maize and sorghum. The results showed that essential oils were anti-fungal at concentrations of 500–2500 ppm or higher. The oil Cymbopogon nardus (referred to as citronella oil) was inhibiting all the Fusarium species growth at 500 ppm and higher. The next most potent inhibitors, the oil from C. citratus (referred to as lemongrass oil) and peppermint oils, were fully inhibitory from a concentration of 1500 and 2000 ppm and higher, respectively. Eucalyptus and neem oils were less effective in inhibiting the growth of Fusarium species tested, irrespective of their concentration. Among the seven essential oils tested against all the Fusarium species, the citronella oil showed highest inhibitory effect (minimum inhibitory concentration, MIC) at = 1500, 2000, 1000, 500 ppm against F. verticillioides, F. oxy sp orum, F. sporotrichioides, F. lateritium mycelial growth development respectively. However clove, lemongrass oil and citronella showed highest inhibitory effect (= 1500 ppm) against F. pr o lif e ra t u m and F. pallidoro-seum respectively. Further lemongrass oil showed highest inhibitory effects at = 1500 and 500 ppm against F. a n t h o p h i -lum and F. lateritum respectively. The least MIC for F. gra -minearum was observed in peppermint oil at = 500 ppm. The results indicate that the tested toxigenic Fusarium spp. are sensitive to the essential oils, and particularly sensitive to the citronella oil. These findings clearly indicate that essential oils should find a practical application to control the growth of Fusarium species in stored maize and sorghum grains.