Seed biology imperative for conservation and restoration of Swertia thomsonii C.B. Clarke-an endemic medicinal plant of Himalaya.

Endemic medicinal plants deserve immediate research priorities as they typically show a limited distribution range, represent few and fragmented populations in the wild and are currently facing anthropogenic threats like overharvesting and habitat degradation. One of the important aspects of ensuring their successful conservation and sustainable utilization lies in comprehending the fundamental seed biology, particularly the dormancy status and seed germination requirements of these plants. Here, we studied the seed eco-physiology and regeneration potential of Swertia thomsonii-an endemic medicinal plant of western Himalaya. We investigated the effect of different pre-sowing treatments, sowing media and sowing depth on seed germination parameters of S. thomsonii. Seeds of S. thomsonii exhibit morphophysiological dormancy (MPD), i.e. when the embryo of the seed is morphologically and/or physiologically immature. Wet stratification at 4 °C for 20 days, pre-sowing treatment with 50 ppm GA3 and pre-sowing treatment with 50 ppm KNO3 were found ideal for overcoming dormancy and enhancing the seed germination of S. thomsonii. Furthermore, seed germination and seedling survival were significantly influenced by pre-sowing treatments, sowing media and sowing depth. The percentage of seed germination and seedling survival got enhanced up to 84-86% and 73-75% respectively when seeds were pre-treated with GA3 or KNO3 and then sown in cocopeat + perlite (1:1) at a depth of 1 cm. The information obtained in the present study outlines an efficient protocol for large-scale cultivation of S. thomsonii thereby limiting the pressure of overexploitation from its natural habitats and may also help in the restoration and conservation of this valuable plant species.

Variability in morphology, phytochemicals and antioxidant activity in Bistorta amplexicaulis (D. Don) Greene populations under variable habitats and altitudes.

Phytochemicals have become significantly important for scientific research since these possess incredibly remarkable health benefits, especially antioxidant potential to scavenge free radicals and combat the harmful effects of oxidative stress caused by adverse environmental factors. The efficacy and quantity of these phytochemicals relies upon numerous factors including the extraction method, solvent polarity and the habitat features in which the plant is growing. In this study we emphasized on phytochemical analysis and antioxidant activity of Bistorta amplexicaulis, an important medicinal plant species from Kashmir Himalaya. We evaluated antioxidant activity using different assays from all the selected sites to enumerate the impact of habitat. The sites were selected based on varying habitat features and altitude. Our results revealed that Ethyl acetate is the potent solvent for the extraction of phytochemicals. Below ground parts exhibited better scavenging activity than the above ground parts. Amongst the sites, we found the maximum antioxidant potential at Site I. A positive correlation was found between antioxidant activity and altitude while soil attributes (OC, OM, N, P, and K) and most of the morphological traits showed a negative correlation. Overall, our study identified the elite populations that could be utilized for mass propagation and harness the ultimate antioxidant potential of B. amplexicaulis.

Induction of apoptosis in human pancreatic MiaPaCa-2 cells through the loss of mitochondrial membrane potential (ΔΨm) by Gentiana kurroo root extract and LC-ESI-MS analysis of its principal constituents.

The objective of the current study was to evaluate the methanolic root extract of Gentiana kurroo for antioxidant and antiproliferative activities as well as to study the effect of the extract on the induction of apoptosis in human pancreatic cancer cell line (MiaPaCa-2). The extract exerted significant antioxidant activity as verified by DPPH, hydroxyl radical, lipid peroxidation and protective oxidative DNA damage assays. The results were comparable to standard antioxidants like α-tocopherol, catechin and BHT used in such experiments. Antioxidant potential of G. kurroo may be attributed to the presence of high phenolic and flavonoid content (73±1.02 and 46±2.05 mg/g extract respectively). The anti-proliferative property of Gentiana kurroo root extract was determined by sulphorhodamine B (SRB) assay against Human colon cancer cell line (HCT-116), Lung carcinoma cell line (A-549), Pancreatic cancer cell line (MiaPaCa-2), Lung cancer cell line (HOP-62) and acute monocytic leukaemia cell line (THP-1). G. kurroo root extract inhibited cancer cell growth depending upon the cell line used and in a dose dependent manner. The extract induced potent apoptotic effects in MiaPaCa-2 cells. The population of apoptotic cells increased from 11.4% in case of control to 49.6% at 100 µg/ml of G. kurroo root extract. The extract also induced a remarkable decrease in mitochondrial membrane potential (ΔΨm) leading to apoptosis of cancer cells used. The main chemical constituents identified by the liquid chromatography-tandem mass spectrometry (LC-ESI-MSMS) were found to be iridoid glucosides (iridoids and secoiridoids), xanthones and flavonoids. Iridoid glucosides are the bitter principles of Gentiana species. Loganic acid, Sweroside, Swertiamarin, Gentiopicroside, Gentisin, Isogentisin, Gentioside, Norswertianolin, Swertianolin, 4″-O-ß-D-glucosyl-6'-O-(4-O-ß-D-glucosylcaffeoyl)-linearoside and Swertisin were the principal compounds present in the methanol root extract of G. kurroo.

Chemical composition, antioxidant and antibacterial activities of the leaf essential oil of Juglans regia L. and its constituents.

The essential oil from the leaves of Juglans regia L. (Juglandaceae) growing wild in Kashmir (India) was obtained by hydrodistillation and analysed by a combination of capillary GC-FID and GC-MS. A total of 38 compounds, representing 92.7% of the oil, were identified and the major components were found to be α-pinene (15.1%), ß-pinene (30.5%), ß-caryophyllene (15.5%) germacrene D (14.4%) and limonene (3.6%). The essential oil and the main individual constituents were screened for antibacterial activity and the essential oil evaluated for antioxidant activity. Antibacterial activity was evaluated using the disc diffusion and microdilution methods against a group of clinically significant Gram-positive (Staphylococcus epidermidis MTCC-435, Bacillus subtilis MTCC-441, Staphylococcus aureus) and Gram-negative bacteria (Proteus vulgaris MTCC-321, Pseudomonas aeruginosa MTCC-1688, Salmonella typhi, Shigella dyssenteriae, Klebsiella pneumonia and Escherichia coli). The essential oil and its major components exhibited broad spectrum inhibition against all the bacterial strains with Gram-positive being more susceptible to the oil than Gram-negative bacteria. Antioxidant activity of the oil was evaluated by the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radicals. In general, the essential oil exhibited high antioxidant activity which was comparable to the reference standards at the same dose (ascorbic acid and butylated hydroxyl toluene, BHT) with IC(50) values of 34.5 and 56.4µg/ml calculated by DPPH and hydroxyl radical scavenging assays respectively.