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Heavy metals are of major concern as they are non-biodegradable and therefore causes health problem to living organisms. In recent days, biosorption by microbes and agro-waste materials have gained increased attention over the conventional methods. Out of twenty six fungi isolated, two species of Aspergillus, Aspergillus niger and Aspergillus terreus exhibited resistance to 1500 mM of Lead on agar medium. A biosorbent was designed by growing these fungal isolates on luffa sponge under shaken condition for 72 h at 30 °C. The percentage of lead adsorption by the designed biosorbent was determined initially by Atomic Adsorption Spectrophotometry and further confirmed by Inductively Coupled Plasma-Optical Emission Spectrometry. Batch methods showed 56–63% of adsorption with A. niger, and 44–59% with A. terreus. Biosorbent pretreated with NaOH showed significant increase in adsorption of lead within 3 min of contact time exhibiting 51% and 46% by A. niger and A. terreus, respectively. The Fourier Transform Infrared Spectroscopy analysis revealed that the functional groups –OH, –NH, and –CH3 present on our designed biosorbents are facilitating the biosorption. The textural properties of the designed biosorbent were analyzed by Scanning Electron Microscopy.

Lovastatin is a competitive inhibitor of the enzyme hydroxymethyl glutaryl coenzyme A reductase (HMGR) in cholesterol biosynthetic pathway and hence used in the treatment of hyperlipidemia. In a previous study, we report a tropical soil isolate, Aspergillus terreus (KM017963), which produces ample amount of lovastatin than its counterpart that are endophytic in origin. Bioinformatic analysis of whole genome sequence of A. terreus (AH007774.1), a soil isolate revealed the presence of gene cluster (AF141924.1 & AF141925.1) responsible for lovastatin production, whereas endophytic fungi including a strain of A. terreus showed no homology with the lovastatin gene cluster. The molecular study was also carried out targeting PCR amplification of the two important genes, lovE (a regulatory gene) and lovF (transcriptional regulatory factor) in genomic and c-DNA of soil and endophytic fungi. Expression of the two genes was successful in A. terreus (KM017963), whereas the same was not achieved in endophytic fungi. To further validate our above findings, in the present study, the whole genome sequencing of A. terreus and a selected endophytic fungus, Diaporthe ampelina (Phomopsis) was performed. Lovastatin gene cluster, when aligned on the consensus sequence of both genomes, the entire lovastatin gene cluster was detected in a single scaffold (1.16) of A.terreus genome. On the contrary, there was a complete absence of lovastatin gene cluster in the genome of D. ampelina (an endophyte). The probable reasons for the absence of lovastatin gene cluster in endophytic fungi are discussed.

Anidulafungin, a new class of antifungal agent used for the treatment of chronic fungal infections, is derived from Echinocandin B nucleus, an intermediate metabolite of Echinocandin B produced by Aspergillus nidulans. The enzyme acylase plays a key role in the bioconversion of Echinocandin B to Echinocandin B nucleus. In the present study, a rapid screening method was used to select an actinomycete capable of producing Echinocandin B acylase. Out of 140 actinomycetes screened for the production of acylase by preliminary qualitative plate assay, 53 were selected. The selected isolates were subjected to quantitative assay under submerged fermentation for the bioconversion of Echinocandin B to Echinocandin B nucleus. Among 53 strains of actinomycetes, two strains (BICC-8848 and BICC-8547) exhibited higher degree of acylase activity. Various physico-chemical parameters were optimised for maximum bioconversion of ECB to ECB nucleus. It was found that the conditions viz. pH 7.0, temperature 26 °C and substrate concentration of about 4 g/L supported higher degree of bioconversion. It was also observed that, as the medium volume increased to 500 mL, the conversion rate was also increased by more than two-folds.

Effects of various cultural conditions on biomass, lipid and Gamma-linolenic acid (GLA) production were investigated in the oleaginous fungus Cunninghamella blakesleeana-JSK2 isolated from soil. The GLA production was influenced by various factors such as growth condition (static and shaken), incubation time, pH, temperature, carbon and nitrogen sources. The results indicated that optimum GLA production (21 %) was obtained when the fungus was grown under shaken condition at 120 rpm for 6 days with optimum pH and temperature of 6 and 28 °C ,respectively. Glucose and potassium nitrate enhanced the GLA production. Urea and sucrose were poor substances for biomass, lipid and GLA production.

Bioremediation is an effective method for the treatment of major metal contaminated sites. Fungi were isolated from soil samples collected from different arsenate contaminated areas across India. An isolate, Penicillium coffeae, exhibited resistance to arsenate up to 500 mM. Results indicated that pretreatment of biomass with alkali (NaOH) enhanced the percentage of adsorption to 66.8 % as compared to that of live and untreated dead biomass whose adsorption was 22.9 % and 60.2 % respectively. The physiological parameters evaluated in this study may help pilot studies aimed at bioremediation of arsenate contaminated effluents using arsenate resistant fungus P. coffeae.

Aim: The aim of the present study was to screen soil and endophytic fungi for production of lovastatin. Methodology: Soil fungi were isolated by dilution plating technique and endophytic fungi from selected medicinal plants by using standard procedures. All isolates were tested for lovastatin production by Solid State Fermentation (SSF) using wheat bran as substrate. Results: The soil isolate, Aspergillus terreus NCBI (KM017963) showed positive for lovastatin (1.0 mg/G DWS) whereas none of the endophytic fungi tested showed positivefor lovastatin production.

We report the complete genome of Aspergillus terreus (KM017963), a tropical soil isolate. The genome sequence is 29 Mb, with a G+C content of 51.12%. The genome sequence of A. terreus shows the presence of the complete gene cluster responsible for lovastatin (an anti-cholesterol drug) production in a single scaffold (1.16).

Diaporthe ampelina was isolated as an endophytic fungus from the root of Commiphora wightii, a medicinal plant collected from Dhanvantri Vana, Bangalore University, Bangalore, India . The whole genome is 59 Mb, contains a total of 905 scaffolds, and has a G+C content of 51.74%. The genome sequence of D. ampelina shows a complete absence of lovastatin (an anticholesterol drug) gene cluster.

Isolates of non-pathogenic Fusarium moniliforme (Fu3, Fu7 and Fu24), F. oxysporum (Fu2, Fu4), F. solani (Fu25) and F. merismoides (Fu1) that were found to be effective in reducing wilt incidence in tomato were tested for their potential to elicit induced systemic resistance (ISR) in tomato. Talc formulations of these isolates derived from liquid fermentation as well as cell elicitors of these cultures were tested. Changes in the phenol and total protein contents and activities of peroxidase and polyphenol oxidase were studied. Isolate Fu3 induced more phenol and total protein contents as well as activities of peroxidase and polyphenol oxidase. Elicitors of Fu2 induced more of these compounds and enzymes. Although Fu1, Fu4 and Fu24 were found to give good control against Fusarium wilt incidence in an earlier study, they were less effective in inducing these defense related compounds. Peroxidase activity was increased when plants were treated with Fu3, Fu4, Fu7, Fu24 and Fu25, whereas polyphenol oxidase act...

Lovastatin is a competitive inhibitor of the enzyme hydroxyl methylglutaryl coenzyme A reductase (HMGR) in cholesterol biosynthetic pathway and hence used in the treatment of hyperlipidemia. Our results revealed that Aspergillus terreus of soil origin produce copious amount of lovastatin than its counterpart that are endophytic in origin. Bioinformatics analysis of whole genome sequence of A. terreus (AH007774.1), a soil isolate revealed the presence of lovastatin gene cluster (AF141924.1 and AF141925.1), whereas, endophytic fungi including a species of A. terreus showed no homology with the lovastatin gene cluster. Molecular studies aimed at generating physical evidence were performed to analyze the expression of lovastatin biosynthetic genes lovE (regulatory gene) and lovF (transcriptional regulatory factor) in soil and endophytic fungi. The target PCR amplification of lovE (1512bp) and lovF (749bp) were successful in a strain of soil isolate, Aspergillus terreus (KM017693), whereas the same was not achieved in endophytic fungi. This is the first report on comparative analysis of complementary DNA sequence of a soil isolate and endophytic fungi, which further substantiate the absence of lovastatin production by endophytic fungi. The significance for the lack of lovastatin by endophytic fungi is also discussed.

Genes responsible for lovastatin production in certain fungi are often clustered (64 kb DNA). In the present study, we report the comparative analysis of the genome of sixty one endophytic fungi and a soil fungus for the presence of lovastatin gene sequences. Nucleotide sequences were obtained from NCBI and aligned with lovastatin gene cluster sequence (AF141924.1& AF141925.1). DNA sequences that are identical to lovastatin gene were identified in Aspergillus terreus, (AH007774.1), a soil isolate, whereas all the other sixty one endophytic fungi including a species of Aspergillus terreus showed very limited or no homology with the lovastatin gene cluster.

Of 13 compounds tested, 11 inhibited malic enzyme activity in Mucor circinelloides, to some degree, at 5 mM. Four of these inhibitors (tartronic acid, morin, catechin and 2,5-dihydroxybenzoic acid) were studied further. Tartronic acid, morin and catechin were competitive inhibitors of malic enzyme (with respect to malate), with apparent Ki values of 0.04 mM, 5 μM and 0.6 mM, respectively. 2,5-Dihydroxybenzoic acid was a non-competitive inhibitor, with respect to malate, and had an apparent Ki value of 0.8 mM. Morin and tartronic acid did not inhibit any other NADPH-generating enzyme studied, although both inhibited malate dehydrogenase. The inhibitory actions of catechin and 2,5-dihydroxybenzoic acid were less specific. All four compounds inhibited malic enzyme, to some extent, when included in the culture medium. This inhibition was not as great as in vitro however and was insufficient to have an effect on lipid metabolism in M. circinelloides.

Induced systemic resistance, one of the mechanisms of biological control is elicited either by oligosaccharides or glycoproteins released from cell wall of fungal bioagents like Trichoderma species. Oligosaccharide elicitors from 10 Trichoderma isolates having biocontrol potential were tested for their ability to elicit ISR in hot pepper against Phytophthora capsici infection. Treatment with elicitors from isolates Th10, Th9, Th33 and Th28 reduced P. capsici infection in hot pepper by 70–80% compared to 100% infection in pathogen inoculated control. Assays of peroxiase (PO), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL) and glucanase revealed that elicitor treatment significantly induced higher enzyme activity in elicitor treated plants compared to control. Induction of more number of isoforms of PO and PPO was also observed. Elicitors from Th10 and Th33 induced two fold increase in PPO and PAL and three-fold increase in PO, while Th28 and Th9 increased PPO and glucanase by two folds. Different enzymes (involved in phenyl propanoid metabolism or hydryolytic enzymes) contributed to ISR in different isolates.

The activity of alcohol oxidase in Aspergillus flavipes was induced by growth on hexadecanol, though highest activities were obtained using a mixture of hexadecanol and olive oil. The enzyme showed a wide range of substrate specificity towards aliphatic primary alcohols from C8 to C18. The preferred substrate was decanol. The enzyme had an optimum pH of 9.5. It also used cis-unsaturated alcohols better than the trans-isomers. ω-Hydroxy fatty acids and α,ω-diols were not attacked.

Malic enzyme was purified 43-fold from Mucor circinelloides. The enzyme was dependent on Mg2+ or Mn2+ for activity, was not active with Dmalate and had a pH optimum at 7.8. The apparent Km values for malate and NADP+ were 488 ΜM and 41 Μm respectively. The Mr of the native enzyme was 160 kDa. Five metabolic analogues of malate: oxaloacetate, tartronic acid, 1-methylenecyclopropane trans-2,3-dicarboxyIic acid, malonic acid and glutaric acid, were found to inhibit malic enzyme activity at 10 mM. Four oleaginous fungi, Mucor circinelloides, Mortierella alpina, Mortierella elongata and Pythium ultimum, were also examined, all possessed a soluble malic enzyme, two also possessed a microsomal malic enzyme.

An intracellular lipase was induced inAspergillus flavipes grown on various triacylglycerols at pH 6.0 and at 30°C, with maximum activity with sunflower oil. The lipase had an optimum pH for activity of 8.8 and retained 30% of its activity at pH 10.0. It had an optimum temperature for activity, measured over 30 min, of 45°C. It was completely inactivated at 60°C within 10 min.