Chitin, the second most abundant polysaccharide in nature after cellulose, is found in the exoskeleton of insects, fungi, yeast, and algae, and in the internal structures of other vertebrates. Chitinases are enzymes that degrade chitin. Chitinases contribute to the generation of carbon and nitrogen in the ecosystem. Chitin and chitinolytic enzymes are gaining importance for their biotechnological applications, especially the chitinases exploited in agriculture fields to control pathogens. Chitinases have a use in human health care, especially in human diseases like asthma. Chitinases have wide-ranging applications including the preparation of pharmaceutically important chitooligosaccharides and N-acetyl D glucosamine, preparation of single-cell protein, isolation of protoplasts from fungi and yeast, control of pathogenic fungi, treatment of chitinous waste, mosquito control and morphogenesis, etc. In this review, the various types of chitinases and the chitinases found in different organisms such as bacteria, plants, fungi, and mammals are discussed.

Aims: The presents study examines the purification and characterization of a chitinase from S. maltophilia SJ602 strain isolated from a soil sample collected from Jamia Hamdard, New Delhi. Methodology and Results: The purification steps included chitin affinity using colloidal chitin as the affinity matrix and column chromatography using Sephadex G-100. The chitinase was purified to 5.85 fold having a yield of 17%. The molecular weight of the chitinase was found to be around 29 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The pH and temperature optima of the purified chitinase were found to be at pH 5.5 and 60 °C, respectively. Conclusion, Significance and Impact of the study: Besides showing a significant yield, the enzyme has a high thermal stability which has its applicability in the recycling of chitin waste.

Filamentous cosmopolitan fungi of the genus Aspergillus can be harmful in two ways, directly they can be opportunistic pathogens causing aspergillosis and indirectly due to aflatoxin production on food products which can lead to aflatoxicosis. Therefore, a number of methods have been proposed so far for detection of the fungi with lowest possible concentration at the earliest. Molecular methods such as PCR and/or in combination with certain techniques have been found to be useful for Aspergillus detection. We discuss here various technologies that have emerged in recent years and can possibly be used for the molecular detection of Aspergillus in an efficient way. These methods like RSIC, C-probe, and inversion probe with pyrosequencing or direct ss/dsDNA detection have been used for the identification of fungal or bacterial pathogens and thus formulate a 'gold standard' for Aspergillus detection.

In vivo modulation of HMG-CoA reductase (HMGR) activity and its impact on artemisinin biosynthesis as well as accumulation were studied through exogenous supply of labeled HMG-CoA (substrate), labeled MVA (the product), and mevinolin (the competitive inhibitor) using twigs of Artemisia annua L. plants collected at the preflowering stage. By increasing the concentration (2-16 lM) of HMG-CoA (3-14 C)

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With the escalating prevalence of malaria in recent years, artemisinin demand has placed considerable stress on its production worldwide. At present, the relative low­yield of artemisinin (0.01­1.1 %) in the source plant (Artemisia annua L. plant) has imposed a serious limitation in commercializing the drug. Amorpha­4, 11­diene synthase (ADS) has been reported a key enzyme in enhancing the artemisinin level in Artemisia annua L. An understanding of the structural and functional correlations of Amorpha­4, 11­diene synthase (ADS) may therefore, help in the molecular up­regulation of the enzyme. In this context, an in silico approach was used to study the ADS3963 (3963 bp) gene cloned by us, from high artemisinin (0.7­0.9% dry wt basis) yielding strain of A. annua L. The full­length putative gene of ADS3963 was found to encode a protein consisting of 533 amino acid residues with conserved aspartate rich domain. The isoelectric point (pI) and molecular weight of the protein were 5.25 and 62.2 kDa, respectively. The phylogenetic analysis of ADS genes from various species revealed evolutionary conservation. Homology modeling method was used for prediction of the 3D structure of ADS3963 protein and Autodock 4.0 version was used to study the ligand binding. The predicted 3D model and docking studies may further be used in characterizing the protein in wet laboratory.

Podophyllotoxin, a well-known naturally occurring aryl tetralin lignan produced by few plant species is used as precursor for the chemical synthesis of the anticancer drugs like etoposide, teniposide and etopophos phosphate. The availability of this lignan is limited due to the scarce occurrence of its natural sources. Further, synthetic approaches for its production are still commercially unacceptable. This paper reports the synthesis of podophyllotoxin by an endophytic fungus Fusarium solani isolated from the roots of Podophyllum hexandrum. The presence of podophyllotoxin in fungal biomass was confirmed and quantified by HPLC and mass spectrometry. The fungus is able to produce 29.0 µg/g podophyllotoxin on dry weight basis.