BackgroundThe production of metabolites via in vitro culture is promoted by the availability of fully defined metabolic pathways. Withanolides, the major bioactive phytochemicals of Withania somnifera, have been well studied for their pharmacological activities. However, only a few attempts have been made to identify key candidate genes involved in withanolide biosynthesis. Understanding the steps involved in withanolide biosynthesis is essential for metabolic engineering of this plant to increase withanolide production.ResultsTranscriptome sequencing was performed on in vitro adventitious root and leaf tissues using the Illumina platform. We obtained a total of 177,156 assembled transcripts with an average unigene length of 1,033 bp. About 13% of the transcripts were unique to in vitro adventitious roots but no unique transcripts were observed in in vitro-grown leaves. A putative withanolide biosynthetic pathway was deduced by mapping the assembled transcripts to the KEGG database, and the expression of candidate withanolide biosynthesis genes -were validated by qRT PCR. The accumulation pattern of withaferin A and withanolide A varied according to the type of tissue and the culture period. Further, we demonstrated that in vitro leaf extracts exhibit anticancer activity against human gastric adenocarcinoma cell lines at sub G1 phase.ConclusionsWe report here a validated large-scale transcriptome data set and the potential biological activity of in vitro cultures of W. somnifera. This study provides important information to enhance tissue-specific expression and accumulation of secondary metabolites, paving the way for industrialization of in vitro cultures of W. somnifera.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-1214-0) contains supplementary material, which is available to authorized users.

Involvement of mitochondrial and nuclear gene mutations in the development of type 2 diabetes (T2D) has been established well in various populations around the world. Previously, we have found the mitochondrial A>G transition at nucleotide position 3243 and 8296 in the T2D patients of Coimbatore population. This study is aimed to screen for the presence of various mitochondrial and nuclear DNA mutations in the T2D patients of Coimbatore to identify most prevalent mutation. This helps in identifying the susceptible individuals based on their clinical phenotype in future. Blood samples were collected from 150 unrelated late-onset T2D patients and 100 age-matched unrelated control samples according to World Health Organization criteria. Genotyping for the selected genes was done by polymerase chain reaction-single strand confirmation polymorphism, direct sequencing, and polymerase chain reaction-restriction fragment length polymorphism. The mitochondrial T>C transition at 8356 and nuclear-encoded GLUT1 gene mutation were found in the selected T2D patients. The T8356C mutation was found in two patients (1.3%), and the clinical characteristics were found to be similar in both the patients whereas GLUT1 gene mutation was found in seven patients. Four out of seven patients showed homozygous (-) genotype and three patients showed heterozygous (±) genotype for the mutant allele XbaI. Among these three patients, one patient was found to have elevated level of urea and creatinine with the history of kidney dysfunction and chronic T2D. Our results suggest that the T8356C and GLUT1 gene mutations may have an important role in developing late-onset T2D in Coimbatore population. Particularly, individuals with GLUT1 gene may develop kidney dysfunction at their later age.

The association of mitochondrial DNA mutation with type 2 diabetes mellitus (T2DM) is well established. In this study we aimed to assess the frequency of A3243G, A8296G, and other mitochondrial mutations with reference to clinical features in the diabetic population of Coimbatore, India. The study group included 150 patients (89 women and 61 men) with T2DM, whereas the control group included 100 nondiabetic people (59 women and 41 men). Genotyping was done by polymerase chain reaction followed by single-strand confirmation polymorphism method. A3243G and A8296G mutations were found to be prevalent in patients with T2DM when compared with the control group. The A3243G mutation was found in two patients, and both these patients showed similar clinical characteristics, thus representing a putative clinical subtype. A8296G mutation was detected in one patient. The same mutation was shared with his mother who was diagnosed to have diabetes mellitus (DM) with neuromuscular disorder. The siblings of the patient did not show any symptoms of DM. Lipid profile and urea and creatinine levels were found to be significantly high (10% and 0.064%) in patients with T2DM compared with control subjects. We concluded that the identification of these mitochondrial point mutations indicates a new genetic predisposition of DM in Coimbatore population.

A novel synthesis of eco-friendly bioplastic film made of chitosan extracted from crab shell is presented in the current study. Crab shell use can result in a reduction in marine waste management. The extracted chitosan has a broad variety of applications in the food industry as a food preservative due to its antibacterial function. A novel procedure for preparing chitosan from crab shells was developed. In the present study, chitosan extracted from crab shell through deproteinization, demineralization and followed by deacetylation. Characterization of extracted chitosan was done by FTIR, and SEM was used to record the photomicrograph image of extracted chitosan. The antibacterial activity of extracted chitosan was studied against Staphylococcus aureus and Escherichia coli. The bio-plastic film was synthesized using the extracted chitosan by adding glycerol as plasticizer along with citric acid, and agarose to the mixture to develop bioplastic film. FTIR vibrations patterns showed stretching of hydroxyl (O-H), amine (N-H) and carbonyl (C-O) groups which indicated the presence of chitosan. The change in the morphology of samples was followed by SEM. It is concluded that the procedure developed in the present work showed that the extracted chitosan is suitable for the preparation of ultra-thin, labile, bioplastic film with good apparent texture. The advantages of the developed product could be its biodegradability, biocompatibility, and effective use as biomedical interface.

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