Microbiome and ecology of a hot spring-microbialite system on the Trans-Himalayan Plateau.

Little is known about life in the boron-rich hot springs of Trans-Himalayas. Here, we explore the geomicrobiology of a 4438-m-high spring which emanates ~70 °C-water from a boratic microbialite called Shivlinga. Due to low atmospheric pressure, the vent-water is close to boiling point so can entropically destabilize biomacromolecular systems. Starting from the vent, Shivlinga's geomicrobiology was revealed along the thermal gradients of an outflow-channel and a progressively-drying mineral matrix that has no running water; ecosystem constraints were then considered in relation to those of entropically comparable environments. The spring-water chemistry and sinter mineralogy were dominated by borates, sodium, thiosulfate, sulfate, sulfite, sulfide, bicarbonate, and other macromolecule-stabilizing (kosmotropic) substances. Microbial diversity was high along both of the hydrothermal gradients. Bacteria, Eukarya and Archaea constituted >98%, ~1% and <1% of Shivlinga's microbiome, respectively. Temperature constrained the biodiversity at ~50 °C and ~60 °C, but not below 46 °C. Along each thermal gradient, in the vent-to-apron trajectory, communities were dominated by Aquificae/Deinococcus-Thermus, then Chlorobi/Chloroflexi/Cyanobacteria, and finally Bacteroidetes/Proteobacteria/Firmicutes. Interestingly, sites of >45 °C were inhabited by phylogenetic relatives of taxa for which laboratory growth is not known at >45 °C. Shivlinga's geomicrobiology highlights the possibility that the system's kosmotrope-dominated chemistry mitigates against the biomacromolecule-disordering effects of its thermal water.

Resilience and receptivity worked in tandem to sustain a geothermal mat community amidst erratic environmental conditions.

To elucidate how geothermal irregularities affect the sustainability of high-temperature microbiomes we studied the synecological dynamics of a geothermal microbial mat community (GMMC) vis-à-vis fluctuations in its environment. Spatiotemporally-discrete editions of a photosynthetic GMMC colonizing the travertine mound of a circum-neutral hot spring cluster served as the model-system. In 2010 a strong geyser atop the mound discharged mineral-rich hot water, which nourished a GMMC continuum from the proximal channels (PC) upto the slope environment (SE) along the mound's western face. In 2011 that geyser extinguished and consequently the erstwhile mats disappeared. Nevertheless, two relatively-weaker vents erupted in the southern slope and their mineral-poor outflow supported a small GMMC patch in the SE. Comparative metagenomics showed that this mat was a relic of the 2010 community, conserved via population dispersal from erstwhile PC as well as SE niches. Subsequently in 2012, as hydrothermal activity augmented in the southern slope, ecological niches widened and the physiologically-heterogeneous components of the 2011 "seed-community" split into PC and SE meta-communities, thereby reclaiming either end of the thermal gradient. Resilience of incumbent populations, and the community's receptiveness towards immigrants, were the key qualities that ensured the GMMC's sustenance amidst habitat degradation and dispersal to discrete environments.

Modernization of Ayurveda: a brief overview of Indian initiatives.

Ayurveda has been the main guiding force in drug discovery from traditional medicine. In concept, this system is rooted in folk or ethnomedicine and in practice it shows further refinement and development in accordance with local traditions. Isolation of active principles from crude drugs, their pharmacological evaluation, therapeutic proving and clinical application resulted in the genesis of modem or so called allopathic medicine. To keep the opportunity alive for further development in traditional as well as modem medicines, it is necessary to have an uninterrupted connection with ethnomedicine. Since the practice of ethnomedicine is based on the age-long indigenous knowledge which has been orally transmitted through generations and sustained in traditions there is an urgent need to document such knowledge. The ongoing strategies adopted in India to document the precious traditional knowledge and conserve medicinal plants are discussed in this communication. India with her rich plant wealth and traditional knowledge about the medicinal use of plants has tremendous scope to provide leadership in ensuring human health and longevity.

Determination of n-alkane constituents and their phenological variation in the epicuticular wax of mature leaves of Nyctanthes arbor-tristis L.

The present communication is a first-time report on the analyses of n-alkane profile of epicuticular wax extracted from the mature leaves of Nyctanthes arbor-tristis L. during a calender year. The composition of n-alkanes revealed hentriacontane (n-C31), tritriacontane (n-C33), tetratriacontane (n-C35) and nonacosane (n-C29) as the major constituents with tritriacontane (n-C33) being the dominant constituent. The cumulative percentage of these four odd-numbered alkanes also showed phenological variation being highest during the fruit ripening stage (average value 63.29%) followed by the flowering stage (mean value 60.74%). The values remained moderate on an average of 54.31% for the rest of the year. This study also confirms the xerophytic feature of the plant having higher proportion of longer carbon chain n-alkanes greater than C31 (dominant peaks are of C33 and C35).