Fluorescence microscopy applied to intracellular transport by microtubule motors

Long-distance transport of many organelles inside eukaryotic cells is driven by the dynein and kinesin motors on microtubule filaments. More than 30 years since the discovery of these motors, unanswered questions include motor–organelle selectivity, structural determinants of processivity, collective behaviour of motors and track selection within the complex cytoskeletal architecture, to name a few. Fluorescence microscopy has been invaluable in addressing some of these questions. Here we present a review of some efforts to understand these sub-microscopic machines using fluorescence.     

Enhanced reproductive success revealed key strategy for persistence of devastated populations in Himalayan food‐deceptive orchid,Dactylorhiza hatagirea

Anthropogenic disturbances adversely affect populations of rare and endemic plants, resulting in reduction of their population size and performance. Among different plant groups, deceptive terrestrial orchids are vulnerable and possess greater extinction risks because of rarity in occurrence. To understand the response of food‐deceptive terrestrial orchids to disturbances, we selected Dactylorhiza hatagirea as our representative species, which is endemic to Himalaya, and studied its natural populations. This species is rare for being habitat specific, pollination limited and threatened in its natural habitats. We tested the hypothesis that disturbances lead to reduction in population size and plant performance of food‐deceptive terrestrial orchids. For assessing the impact of disturbance, two contrasting groups, heavily devastated (HD) and lightly devastated (LD), were identified on the basis of frequency and intensity of disturbance (harvesting of plant for tubers) by interviewing local people, medicinal plant extractors and shepherds. HD sites, in comparison to LD sites, were found to have smaller population sizes, but showed an increase in plant growth traits (plant height, specific leaf area, leaf N and specific shoot length). Similarly, plants at HD sites were found to have invested less in inflorescence (inflorescence size, inflorescence length, inflorescence length fraction and flowers per length), but despite that showed higher reproductive success. This was a clear indication of enhanced performance of its populations driven by disturbances. Our findings suggested that food‐deceptive species in small populations tend to reduce the probability of population extinction and have the capability to recover rapidly if conserved in time.     

Bio-prospectus of cadmium bioadsorption by lactic acid bacteria to mitigate health and environmental impacts

Applied Microbiology and Biotechnology - Foodstuffs and water are the key sources of cadmium biomagnifiaction. The available strategies to mitigate this problem are unproductive and expensive for...     

Chemical Composition,Cytotoxic and Antibacterial Activities of Essential Oils of Cultivated Clones of Juniperus communis and Wild Juniperus Species

Needles of seven cultivated clones (C1 – C7) of Juniperus communis at lower altitude and three wild Juniperus species (J. communis, J. recurva and J. indica) at higher altitudes were investigated comparatively for their essential oils (EOs) yields, chemical composition, cytotoxic and antibacterial activities. The EOs yields varied from 0.26 to 0.56% (v/w) among samples. Sixty‐one volatile components were identified by gas chromatography‐mass spectrometry (GC/MS) and quantified using gas chromatography GC (FID) representing 82.5 – 95.7% of the total oil. Monoterpene hydrocarbons (49.1 – 82.8%) dominated in all samples (α‐pinene, limonene and sabinene as major components). Principal component analysis (PCA) of GC data revealed that wild and cultivated Juniperus species are highly distinct due to variation in chemical composition. J. communis (wild species) displayed cytotoxicity against SiHa (human cervical cancer), A549 (human lung carcinoma) and A431 (human skin carcinoma) cells (66.4 ± 2.2%, 74.4 ± 1.4% and 57.4 ± 4.0%), respectively, at 200 μg/ml. EOs exhibited better antibacterial activity against Gram‐positive bacteria than against Gram‐negative bacteria with the highest zone of inhibition against Staphylococcus aureus MTCC 96 (19.2 ± 0.7) by clone‐7. As per the conclusion of the findings, EOs of clone‐2, clone‐5 and clone‐7 can be suggested to the growers of lower altitude, as there is more possibility of uses of these EOs in food and medicinal preparations.     

Torvonin-A,a spirostane saponin from Solanum torvum leaves

A new steroidal saponin, torvonin-A, has been isolated from S. torvum leaves and its structure has been established as neochlorogenin-3-O-β-L-rhamnopyranosyl (1→2)β-L-rhamnopyranoside.     

Latex extractables of Calotropis gigantea

The hexane and methanol soluble extract of the latex coagulum of Calotropis gigantea afforded two new triterpene esters, viz. 3′-methylbutanoates of α-amyrin and ψ-taraxasterol, besides the known 3′-methylbutanoates of three triterpene alcohols. The compositions of the alkane fraction, total triterpene alcohol fraction, and free, acetyl and 3′-methylbutanoyl triterpene alcohol fractions of the extract were determined.