Insights into morphological and physio-biochemical adaptive responses in mungbean (Vigna radiata L.) under heat stress.

Mungbean (Vigna radiata L. Wilczek) is an important food legume crop which contributes significantly to nutritional and food security of South and Southeast Asia. The crop thrives in hot and humid weather conditions, with an optimal temperature range of 28°-35°C, and is mainly cultivated under rainfed environments. However, the rising global temperature has posed a serious threat to mungbean cultivation. Optimal temperature is a vital factor in cellular processes, and every crop species has evolved with its specific temperature tolerance ability. Moreover, variation within a crop species is inevitable, given the diverse environmental conditions under which it has evolved. For instance, various mungbean germplasm can grow and produce seeds in extreme ambient temperatures as low as 20°C or as high as 45°C. This range of variation in mungbean germplasm for heat tolerance plays a crucial role in developing heat tolerant and high yielding mungbean cultivars. However, heat tolerance is a complex mechanism which is extensively discussed in this manuscript; and at the same time individual genotypes have evolved with various ways of heat stress tolerance. Therefore, to enhance understanding towards such variability in mungbean germplasm, we studied morphological, anatomical, physiological, and biochemical traits which are responsive to heat stress in plants with more relevance to mungbean. Understanding heat stress tolerance attributing traits will help in identification of corresponding regulatory networks and associated genes, which will further help in devising suitable strategies to enhance heat tolerance in mungbean. The major pathways responsible for heat stress tolerance in plants are also discussed.

Growth optimization, free radical scavenging and antibacterial potential of Chlorella sp. SRD3 extracts against clinical isolates.

AIM: The aim of present work was to explore the potential of Chlorella sp. SRD3 extracts for antioxidant and antibacterial activity along with the evaluation of minimum inhibitory concentration (MIC) and haemolytic activity to detect RBC cell damage. METHODS AND RESULTS: Screening and isolation of microalgae was performed using bold basal medium under normal illuminance (at 27°C) and microscopic observation. Growth of the microalgae was optimized using a different medium and light source. The isolated microalgae incubated under fluorescent light when cultured in F/2 medium showed a highest dry biomass yield of 3·77 ± 0·1 g l-1 , when compared to the growth under direct sunlight (2·74 ± 0·07 g dwt l-1 ). The quantitative analysis of extracts revealed higher phenols, flavonoids and proanthocyanidins in ethyl acetate and hexane extracts followed by methanol. The antioxidant activity of extracts was tested against 1-diphenyl-2-picrylhydrazyl and ABTS radical, its reducing power assay was performed. From antibacterial activity, the two extracts showed better inhibition against Gram-negative bacteria. Also, they resulted in very low MIC values with effective activity against pathogens. In haemolytic activity, no haemolysis occurred, when the concentration (µg ml-1 ) was below 64 for methanol and 32 for ethyl acetate extract. In addition, Chlorella sp. extracts were characterized by GC-MS analysis to detect the major compounds. CONCLUSION: The polar extracts revealed satisfactory results against the clinical isolates and the compounds responsible were reflected in the GC-MS spectrum. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study revealed significant biological potentials of the green alga, Chlorella sp. such as antioxidant, antibacterial and hemolytic activities. Therefore, this vital source might serve as a cost-effective, alternative choice to the pharmaceutical and food industries in the near future.

Differential accumulation of ß-carotene and tissue specific expression of phytoene synthase (MaPsy) gene in banana (Musa sp) cultivars.

An experiment was conducted with twelve major Indian banana cultivars to investigate the molecular relationship between the differential accumulation of ß-carotene in peel and pulp of the banana fruit and carotenoid biosynthetic pathway genes. The high performance liquid chromatography showed that all banana cultivars accumulated two-three fold more ß-carotene in non-edible portion of the banana fruit. However, Nendran, a famous orange fleshed cultivar of South India, had high ß-carotene content (1362 µg/100 g) in edible pulp. The gene encoding Musa accuminata phytoene synthase (MaPsy) was successfully amplified using a pair of degenerate primers designed from Oncidium orchid. The deduced amino acid sequences shared a high level of identity to phytoene synthase gene from other plants. Gene expression analysis confirmed the presence of two isoforms (MaPsy1 and MaPsy2) of MaPsy gene in banana fruits. Presence of two isoforms of MaPsy gene in peel and one in pulp confirmed the differential accumulation of ß-carotene in banana fruits. However, Nendran accumulated more ß-carotene in edible pulp due to presence of both the isoforms of MaPsy gene. Thus, carotenoid accumulation is a tissue specific process strongly dependent on differential expression pattern of two isoforms of MaPsy gene in banana.

Phytochemical constituents of some Indian medicinal plants.

Alkaloids, tannins, saponins, steroid, terpenoid, flavonoids, phlobatannin and cardie glycoside distribution in seven medicinal plants belonging to different families were assessed and compared. The medicinal plants investigated were Aegle marmelos, Cynodon dactylon, Eclipta prostrata, Moringa pterygosperma, Pongamia pinnata, Sida acuta and Tridax procumbens. The significance of the plants in traditional medicine and the importance of the distribution of these chemical constituents were discussed with respect to the role of these plants in ethnomedicine in India.

Hypolipidemic activity of Eclipta prostrata (L.) L. leaf extract in atherogenic diet induced hyperlipidemic rats.

In atherogenic diet induced hyperlipidemic model, the rats receiving treatment with the aqueous extract of the leaves of E. prostrata showed significant reduction in total cholesterol, triglyceride, total protein and elevation in high density lipoprotein cholesterol. The aqueous extract of E. prostrata was found to possess significant hypolipidemic activity. The results also suggest that E. prostrata leaf extract at 100 and 200 mg/kg b.wt. concentrations is an excellent lipid-lowering agent.

Traditional Medicinal Knowledge on Moringa concanensis Nimmo of Perambalur District, Tamilnadu.

Moringa concanensis Nimmo (Moringaceae) is one of the important medicinal plant. It is restricted in its distribution. The present study was aimed at recording traditional knowledge about this plant in various localities of Perambalur district, Tamilnadu. The medicinally useful part, drug preparation, mode of administration and the disease which can be treated have been discussed in this paper.

Preliminary phytochemical investigation and antibacterial activity of Phyllanthus amarus Schum & Thorn.

The aqueous extract of Phyllanthus amarus Schum & Thorn, was selected for preliminary phytochemical and antibacterial activity against human pathogens. Minimum inhibitory concentration was performed by broth dilution method and the zone of inhibition was studied by agar disc diffusion method at concentrations of 10 and 20 mg/ml in DMSO (Dimethyl Sulfoxide). The results revealed the antimicrobial activity of extract against the the strains of microorganisms concentrations in ranges of 60 and 500 µg/ml. Aqueous extract of leaves and roots of Phyllanthus amarus exhibited significant antibacterial activity against eight test bacteria like Staphylococcus aureus, Bacillus subtilis, Staphylococcus albus, Streptococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Proteus vulgaris. The plant under study revealed the presence of alkaloids, phytosterols, phenolic compounds and tannins, proteins and amino acids , lignins and saponins.

MASS MULTIPLICATION OF THE INDIAN MEDICINAL PLANT Tylophora Indica (Burm.f.) Merr.

Tylophora indica (Burm.f) Merr. (ASCLEPIDACEAE) is an important Indian medicinal plant. It is called "ASTHMA KODI" OR "NANJARUPPAN" IN Tamil in the Siddha system of medicine. Tamil medical literature reveal that it is an ideal plant medicine for respiratory problems and is also a cardiac tonic. For medicinal purposes it is collected only from the wild. It has not yet been brought under cultivation. Its taxonomy, morphology, ecology and medicinal uses were studied. Since, tissue-culture is a costly technology and requiring a high-tech laboratory a low-cost mass- multiplication technique has been invented through water-culture experiments, in order to make its saplings available to the interested herbal farmers in a larger scale. The results are reported in this paper, which will be of immense help and use to the herbal farmers.

Production of a thermophilic, extracellular alkaline protease by Bacillus stearothermophilus AP-4.

A thermophilic Bacillus stearothermophilus strain AP-4 excreting a thermostable alkaline protease, was isolated from a local compost. Maximum activity of protease (250 U/ml) was after 36 h growth in broth at pH 9.0 and at 55°C. The protease was optimally active at pH 9.0 and 55°C and was stable in 5 mM CaCl2. The enzyme was completely inactivated by PMSF, EDTA and ß-mercaptoethanol. It is therefore a metal ion-dependent, alkaline, serine protease.

Clinico Mycological Study of Dermatophytosis in a Coastal Area.

Clinico-mycological features of one hundred patients suffering from tinea cruris are reported. Ninety two per cent are males and 79% are in the age group of 11-39 years. Involvement of axillae is seen in four penile involvement in five patients. 'Twenty-eight patients have tinea corporis and nine tinea vesicolor also. Seventy seven patients show isolation of dernm-tophytes by culture. The commonest species of dermatophytes is Trichophyron rubrum (57.1%) followed by T. mentagraphytes (31.20/o), Epidermophyton floccosum (6.5%), T. violaceum (3.9%) and T. verrucosum (1.3%). The findings are discussed.