Enhanced catharanthine and vindoline production in suspension cultures of Catharanthus roseus by ultraviolet-B light

Suspension cultures of Catharanthus roseus were used to evaluate ultraviolet-B (UV-B) treatment as an abiotic elicitor of secondary metabolites. A dispersed cell suspension culture from C. roseus leaves in late exponential phase and stationary phase were irradiated with UV-B for 5 min. The stationary phase cultures were more responsive to UV-B irradiation than late exponential phase cultures. Catharanthine and vindoline increased 3-fold and 12-fold, respectively, on treatment with a 5-min UV-B irradiation

UV-B-induced signaling events leading to enhanced-production of catharanthine in Catharanthus roseus cell suspension cultures

<p>Abstract</p> <p>Background</p> <p>Elicitations are considered to be an important strategy towards improved <it>in vitro </it>production of secondary metabolites. In cell cultures, biotic and abiotic elicitors have effectively stimulated the production of plant secondary metabolites. However, molecular basis of elicitor-signaling cascades leading to increased production of secondary metabolites of plant cell is largely unknown. Exposure of <it>Catharanthus roseus </it>cell suspension culture to low dose of UV-B irradiation was found to increase the amount of catharanthine and transcription of genes encoding tryptophan decarboxylase (<it>Tdc</it>) and strictosidine synthase (<it>Str</it>). In the present study, the signaling pathway mediating UV-B-induced catharanthine accumulation in <it>C. roseus </it>suspension cultures were investigated.</p> <p>Results</p> <p>Here, we investigate whether cell surface receptors, medium alkalinization, Ca²⁺influx, H₂O₂, CDPK and MAPK play required roles in UV-B signaling leading to enhanced production of catharanthine in <it>C. roseus </it>cell suspension cultures. <it>C. roseus </it>cells were pretreated with various agonists and inhibitors of known signaling components and their effects on the accumulation of <it>Tdc </it>and <it>Str </it>transcripts as well as amount of catharanthine production were investigated by various molecular biology techniques. It has been found that the catharanthine accumulation and transcription of <it>Tdc </it>and <it>Str </it>were inhibited by 3–4 fold upon pretreatment of various inhibitors like suramin, N-acetyl cysteine, inhibitors of calcium fluxes, staurosporine <it>etc</it>.</p> <p>Conclusion</p> <p>Our results demonstrate that cell surface receptor(s), Ca²⁺influx, medium alkalinization, CDPK, H₂O₂and MAPK play significant roles in UV-B signaling leading to stimulation of <it>Tdc </it>and <it>Str </it>genes and the accumulation of catharanthine in <it>C. roseus </it>cell suspension cultures. Based on these findings, a model for signal transduction cascade has been proposed.</p

Progress of research under scheme on pearl culture, 1974-78

The lucrative pearl fishery in the Gulf of Mannar could not be conducted after 1961 due to the paucity of oysters in the natural beds. So the only way to have continuous supply of pearls is the production of cultured pearls utilising the available oyster resources. This needs preliminary investigations. Only when the cultured pearl production technology, farming and other allied techniques are perfected, a venture can be made in the direction of commercial production. To perfect the technique of cultured pearl production and farming, the Pearl Culture Scheme of Department of Fisheries, Tamil Nadu Government was started in collaboration with Central Marine Fisheries Research Institute, Tuticorin. The programme commenced functioning from 8-2-1974

MODULATING THE BIOSYNTHESIS OF A BIOACTIVE STEROIDAL SAPONIN, CHOLESTANOL GLUCOSIDE BY LASIODIPLODIA THEOBROMAE USING ABIOTIC STRESS FACTORS

Objective: The present study investigates the modulation of cholestanol glucoside (CG) biosynthesis by Lasiodiplodia theobromae in response to oxidative, osmotic and heat shock stresses.Methods: The fungal cultures were subjected to oxidative stress by supplementing the culture media with menadione or H2O2 to the desired final concentrations. Osmotic stress was implemented by the addition of the desired concentrations of NaCl or sorbitol. For heat-shock treatments, the fungal cultures were subjected to required temperature variations. Each stress treatment was carried out at different time points so as to include different stages of fungal growth.Results: Oxidative stress enhanced CG yield by the fungus by 1.8-fold (88.3±0.6 mg/l) where as osmotic and heat shock stresses proved to be poor enhancers of CG production.Conclusions: Our findings enable a cost-effective, large scale production of CG by L. theobromae and more over throws light on the possible antioxidant activity of the compound in the organism.Â

Land Use Land Cover (LULC) Dynamics by CA-ANN and CA-Markov Model Approaches: A Case Study of Ranipet Town, India

The present study analyzed the spatio-temporal variations in the Land Use Land Cover types within Ranipet Municipal town in Ranipet District, Tamil Nadu State, India, using two different platforms (QGIS and IDRISI Selva v.17.0). The possible parameters driven the net changes in the Land Use Land Cover (LULC) types were also incorporated for the analysis. Results revealed the positive net changes in the built-up area are about 26.8%, and combined other classes like vegetation, barren land, and water bodies have net negative changes during 1997-2019. Particularly barren land was found to have a reduction of 17.4% due to the massive industrialization in the study area. Further, the LULC maps were used for future prediction (2029) using the dynamic models of CA-ANN (Cellular Automata and Artificial Neural Network) and CA-Markov. Predicted maps yielded a kappa index of 81.6% and 82.6% for CA-ANN and CA-Markov, representing their respective accuracy levels. The CA-Markov model is extended for determining the probable long-term changes for 2080 in LULC with a kappa index of 76.2%. Compared to the CA-ANN model using the QGIS platform, CA-Markov provided better analysis, particularly from one cell to the other. According to the survey and the ground truth in the locality, industrialization and occupational shift were the most influential drivers of LULC dynamics. Moreover, the results of this study assist the stakeholders in the decision-making process for future sustainable land use management

Enhanced cytotoxic and apoptosis inducing activity of lycopene oxidation products in different cancer cell lines

Currently, upon understanding the metabolomics of carotenoids, it is important to address the key role of carotenoid derived products. In this regard, aim of the study was to elucidate and explore the role of lycopene (LYC) oxidative products generated through autoxidation (AOL) or chemical (KMnO4) oxidation (COL) against proliferation of selected cancer cells. Preliminary, we investigated the effect of LYC on cell viability of various cancer cell lines (PC-3, MCF-7, A431, HepG2, HeLa and A549). Based on the results of LYC treatment on cell cytotoxicity levels, MCF-7, PC-3 and HeLa cell lines were further tested with AOL and COL products. The decreased cell viability with depleted GSH and increased MDA levels were observed when treated with COL products than control, LYC and AOL. In addition, COL products increased ROS levels and percent apoptosis. The typical morphological changes and nuclear condensations showed that COL products have anti-proliferation and apoptosis inducing activity. Based on results, we hypothesized that ROS generation by LYC oxidation products may be one of intermediate step involved in apoptosis. The redox status and therapeutic approach of COL products in modulating ROS and induction of apoptosis in cancer cells were reported for the first time, to our knowledge. To conclude, COL products involves in cancer growth inhibition efficiently than intact LYC and AOL. Hence, there is a great potential for synthesizing or producing such carotenoid oxidation products to augment cancer complication