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Centellosides viz., asiatic acid, madecassic acid, asiaticoside, madecassoside, are the major bioactive molecules in Centella asiatica. In this study madecassic acid:asiatic acid, madecassoside:asiaticoside (C6-hydroxylation versus non-hydroxylation) and asiaticoside:asiatic acid, madecassoside:madecassic acid (C28-glycoside versus aglycone) ratios in 50 C. asiatica accessions originally collected from their natural habitats in south India and grown under identical ecological conditions for six generations were determined using validated HPTLC-densitometry protocols. Asiatic acid, madecassic acid, asiaticoside and madecassoside contents ranged from 0.00–0.29% (average 0.03 ± 0.06%; 28 accessions recorded asiatic acid content as zero), 0.02–0.72% (0.12 ± 0.13%), 0.04–2.41% (0.44 ± 0.52%) and 0.15–5.27% (1.59 ± 1.26%), respectively. Distinctly, C6-hydroxylated (madecassic acid:asiatic acid 4.00, madecassoside:asiaticoside 3.61) and C28-glycosylated (asiaticoside:asiatic acid 14.67, madecassoside: madecassic acid 13.25) centellosides dominated over the respective non-derivatized entities. Our results infer that both C6-hydroxylation by CYP450-dependent monooxygenases and C28-glycosylation by UDP-Glc glucosyltransferases are dominant bioconversion steps in C. asiatica. Besides, this study discovered six elite lines of C. asiatica, with their (asiaticoside + madecassoside) contents above the industrial benchmark (≥ 4%) from south India. Two elite clones with asiaticoside contents ≥ 2% were also identified. Standardization of the agrotechniques of these elite lines could lead to their industrial applications. Further, this study emphasizes the need for standardizing all four centellosides as biomarkers in C. asiatica raw drugs, pharmaceutical and cosmetic products.

There is an urgent need to develop novel compounds that prevent the deleterious effects of opioids such as fentanyl on minute ventilation while, if possible, preserving the analgesic actions of the opioids. We report that L-glutathione ethyl ester (GSHee) may be such a novel compound. In this study, we measured tail flick latency (TFL), arterial blood gas (ABG) chemistry, Alveolar-arterial gradient, and ventilatory parameters by whole body plethysmography to determine the responses elicited by bolus injections of fentanyl (75 μg/kg, IV) in male adult Sprague–Dawley rats that had received a bolus injection of GSHee (100 μmol/kg, IV) 15 min previously. GSHee given alone had minimal effects on TFL, ABG chemistry and A-a gradient whereas it elicited changes in some ventilatory parameters such as an increase in breathing frequency. In vehicle-treated rats, fentanyl elicited (1) an increase in TFL, (2) decreases in pH, pO2 and sO2 and increases in pCO2 (all indicative of ventilatory depression), (3) an increase in Alveolar-arterial gradient (indicative of a mismatch in ventilation-perfusion in the lungs), and (4) changes in ventilatory parameters such as a reduction in tidal volume, that were indicative of pronounced ventilatory depression. In GSHee-pretreated rats, fentanyl elicited a more prolonged analgesia, relatively minor changes in ABG chemistry and Alveolar-arterial gradient, and a substantially milder depression of ventilation. GSHee may represent an effective member of a novel class of thiolester drugs that are able to prevent the ventilatory depressant effects elicited by powerful opioids such as fentanyl and their deleterious effects on gas-exchange in the lungs without compromising opioid analgesia.

As scientific and technical knowledge advances, research on biomedical micro-electromechanical systems (bio-MEMS) is also developing towards lab-on-a-chip (LOC) devices. A digital microfluidic (DMF) system specialized for an electrowetting- on-dielectric (EWOD) mechanism is a promising technique for such point-of-care systems. EWOD microfluidic biochemical analytical systems provide applications over a broad range in the lab-on-a-chip field. In this report, we treated extraction of cell-free DNA (cf-DNA) at a small concentration from a mouse embryo culture medium (2.5 days & 3.5 days) with electro-wetting on a dielectric (EWOD) platform using bio-reagents of micro-scale quantity. For such extraction, we modified a conventional method of genomic-DNA (g-DNA) extraction using magnetic beads (MB). To prove that extraction of cf-DNA with EWOD was accomplished, as trials we extracted designed-DNA (obtained from Chang Gung Memorial Hospital (CGMH), Taiwan which shows properties similar to that of cf-DNA). Using that designed DNA, extraction with both conventional and EWOD methods has been performed; the mean percentage of extraction with both methods was calculated for a comparison. From the cycle threshold (Ct) results with a quantitative polymerase chain reaction (q-PCR), the mean extraction percentages were obtained as 14.8 percent according to the conventional method and 23 percent with EWOD. These results show that DNA extraction with EWOD appears promising. The EWOD extraction involved voltage 100 V and frequency 2 kHz. From this analysis, we generated a protocol for an improved extraction percentage on a EWOD chip and performed cf-DNA extraction from an embryo-culture medium (KSOM medium) at 3.5 and 2.5 days. The mean weight obtained for EWOD-extracted cf-DNA is 0.33 fg from the 3.5-day sample and 31.95 fg from the 2.5-day sample. All these results will pave a new path towards a renowned lab-on-a-chip concept.

Learning in neuronal networks based on Hebbian principle has been shown to lead to destabilizing effects. Mechanisms have been identified that maintain homeostasis in such networks. However, the way in which these two opposing forces operate to support learning while maintaining stability is an active area of research. In this study, using neuronal networks grown on multi electrode arrays, we show that theta burst stimuli lead to persistent changes in functional connectivity along specific paths while the network maintains a global homeostasis. Simultaneous observations of spontaneous activity and stimulus evoked responses over several hours with theta burst training stimuli shows that global activity of the network quantified from spontaneous activity, which is disturbed due to theta burst stimuli is restored by homeostatic mechanisms while stimulus evoked changes in specific connectivity paths retain a memory trace of the training.

Heavy metal contamination in water causes severe adverse effects on human health. Millions of tons of kernel shell are produced as waste from oil palm plantation every year. In this study, palm oil kernel shell (PKS), an agricultural waste is utilized as effective adsorbent for the removal of heavy metals, namely; Cr6+, Pb2+, Cd2+ and Zn2+ from water. Different parameters of adsorptions; solution pH, adsorbent dosage, metal ions concentration and contact time were optimized. The PKS was found to be effective in the adsorption of heavy metal ions Cr6+, Pb2+, Cd2+ and Zn2+ from water with percentage removal of 98.92%, 99.01%, 84.23% and 83.45%, respectively. The adsorption capacities for Cr6+, Pb2+, Cd2+ and Zn2+ were found to be 49.65 mg/g, 43.12 mg/g, 49.62 mg/g and 41.72 mg/g respectively. Kinetics of adsorption process were determined for each metal ion using different kinetic models like the pseudo-first order, pseudo-second order and parabolic diffusion models. For each metal ion the pseudo-second order model fitted well with correlation coefficient, R2 = 0.999. Different isotherm models, namely Freundlich and Langmuir were applied for the determination of adsorption interaction between metal ions and PKS. Adsorption capacity was also determined for each of the metal ions. PKS was found to be very effective adsorbent for the treatment of heavy metal contaminated water and short time of two hours is required for maximum adsorption. This is a comprehensive study almost all the parameters of adsorptions were studied in detail. This is a cost effective and greener approach to utilize the agricultural waste without any chemical treatment, making it user friendly adsorbent.

Carnivorous plants of the genus Nepenthes supplement their nutrient deficiency by capturing arthropods or by mutualistic interactions, through their leaf-evolved biological traps (pitchers). Though there are numerous studies on these traps, mostly on their prey capture mechanisms, the gas composition inside them remains unknown. Here we show that, Nepenthes unopened pitchers are CO2-enriched ‘cavities’, when open they emit CO2, and the CO2 gradient around open pitchers acts as a cue attracting preys towards them. CO2 contents in near mature, unopened Nepenthes pitchers were in the range 2500–5000 ppm. Gas collected from inside open N. khasiana pitchers showed CO2 at 476.75 ± 59.83 ppm. CO2-enriched air-streaming through N. khasiana pitchers (at 619.83 ± 4.53 ppm) attracted (captured) substantially higher number of aerial preys compared to air-streamed pitchers (CO2 at 412.76 ± 4.51 ppm). High levels of CO2 dissolved in acidic Nepenthes pitcher fluids were also detected. We demonstrate respiration as the source of elevated CO2 within Nepenthes pitchers. Most unique features of Nepenthes pitchers, viz., high growth rate, enhanced carbohydrate levels, declined protein levels, low photosynthetic capacity, high respiration rate and evolved stomata, are influenced by the CO2-enriched environment within them.

Enterotoxigenic Escherichia coli (ETEC) cause more than 500,000 deaths each year in the developing world and are characterized on a molecular level by the presence of genes that encode the heat-stable (ST) and/or heat-labile (LT) enterotoxins, as well as surface structures, known as colonization factors (CFs). Genome sequencing and comparative genomic analyses of 94 previously uncharacterized ETEC isolates demonstrated remarkable genomic diversity, with 28 distinct sequence types identified in three phylogenomic groups. Interestingly, there is a correlation between the genomic sequence type and virulence factor profiles based on prevalence of the isolate, suggesting that there is an optimal combination of genetic factors required for survival, virulence and transmission in the most successful clones. A large-scale BLAST score ratio (LS-BSR) analysis was further applied to identify ETEC-specific genomic regions when compared to non-ETEC genomes, as well as genes that are more associated with clinical presentations or other genotypic markers. Of the strains examined, 21 of 94 ETEC isolates lacked any previously identified CF. Homology searches with the structural subunits of known CFs identified 6 new putative CF variants. These studies provide a roadmap to exploit genomic analyses by directing investigations of pathogenesis, virulence regulation and vaccine development.

The current study sought the effective mitigation measure of seawater-induced damage to mung bean plants by exploring the potential roles of acetic acid (AA). Principal component analysis (PCA) revealed that foliar application of AA under control conditions improved mung bean growth, which was interlinked to enhanced levels of photosynthetic rate and pigments, improved water status and increased uptake of K+, in comparison with water-sprayed control. Mung bean plants exposed to salinity exhibited reduced growth and biomass production, which was emphatically correlated with increased accumulations of Na+, reactive oxygen species and malondialdehyde, and impaired photosynthesis, as evidenced by PCA and heatmap clustering. AA supplementation ameliorated the toxic effects of seawater, and improved the growth performance of salinity-exposed mung bean. AA potentiated several physio-biochemical mechanisms that were connected to increased uptake of Ca2+ and Mg2+, reduced accumulation of toxic Na+, improved water use efficiency, enhanced accumulations of proline, total free amino acids and soluble sugars, increased catalase activity, and heightened levels of phenolics and flavonoids. Collectively, our results provided new insights into AA-mediated protective mechanisms against salinity in mung bean, thereby proposing AA as a potential and cost-effective chemical for the management of salt-induced toxicity in mung bean, and perhaps in other cash crops.

Hemorphins are atypical endogenous opioid peptides produced by the cleavage of hemoglobin beta chain. Several studies have reported the therapeutic potential of hemorphin in memory enhancement, blood regulation, and analgesia. However, the mode of interaction of hemorphin with its target remains largely elusive. The decapeptide LVV-hemorphin-7 is the most stable form of hemorphin. It binds with high affinity to mu-opioid receptors (MOR), angiotensin-converting enzyme (ACE) and insulin-regulated aminopeptidase (IRAP). In this study, computational methods were used extensively to elucidate the most likely binding pose of mammalian LVV-hemorphin-7 with the aforementioned proteins and to calculate the binding affinity. Additionally, alignment of mammalian hemorphin sequences showed that the hemorphin sequence of the camel harbors a variation – a Q > R substitution at position 8. This study also investigated the binding affinity and the interaction mechanism of camel LVV-hemorphin-7 with these proteins. To gain a better understanding of the dynamics of the molecular interactions between the selected targets and hemorphin peptides, 100 ns molecular dynamics simulations of the best-ranked poses were performed. Simulations highlighted major interactions between the peptides and key residues in the binding site of the proteins. Interestingly, camel hemorphin had a higher binding affinity and showed more interactions with all three proteins when compared to the canonical mammalian LVV-hemorphin-7. Thus, camel LVV-hemorphin-7 could be explored as a potent therapeutic agent for memory loss, hypertension, and analgesia.

We predict the induction or suppression of magnetism in the valence shell of physisorbed and chemisorbed organic molecules on graphene occurring on the femtosecond time scale as a result of core level excitations. For physisorbed molecules, where the interaction with graphene is dominated by van der Waals forces and the system is non-magnetic in the ground state, numerical simulations based on density functional theory show that the valence electrons relax towards a spin polarized configuration upon excitation of a core-level electron. The magnetism depends on efficient electron transfer from graphene on the femtosecond time scale. On the other hand, when graphene is covalently functionalized, the system is magnetic in the ground state showing two spin dependent mid gap states localized around the adsorption site. At variance with the physisorbed case upon core-level excitation, the LUMO of the molecule and the mid gap states of graphene hybridize and the relaxed valence shell is not magnetic anymore.

Carnivorous plants of the genus Nepenthes supplement their nutrient deficiency by capturing arthropods or by mutualistic interactions, through their leaf-evolved biological traps (pitchers). Though there are numerous studies on these traps, mostly on their prey capture mechanisms, the gas composition inside them remains unknown. Here we show that, Nepenthes unopened pitchers are CO2-enriched ‘cavities’, when open they emit CO2, and the CO2 gradient around open pitchers acts as a cue attracting preys towards them. CO2 contents in near mature, unopened Nepenthes pitchers were in the range 2500–5000 ppm. Gas collected from inside open N. khasiana pitchers showed CO2 at 476.75 ± 59.83 ppm. CO2-enriched air-streaming through N. khasiana pitchers (at 619.83 ± 4.53 ppm) attracted (captured) substantially higher number of aerial preys compared to air-streamed pitchers (CO2 at 412.76 ± 4.51 ppm). High levels of CO2 dissolved in acidic Nepenthes pitcher fluids were also detected. We demonstrate respiration as the source of elevated CO2 within Nepenthes pitchers. Most unique features of Nepenthes pitchers, viz., high growth rate, enhanced carbohydrate levels, declined protein levels, low photosynthetic capacity, high respiration rate and evolved stomata, are influenced by the CO2-enriched environment within them.

Melocanna baccifera is a unique bamboo which produces the largest fruits in the grass family. Its gregarious flowering once in 45–50 years in north east India and adjacent regions is a botanical enigma, resulting in a glut of fruits. Proper utilization of M. baccifera fruits is not extant and huge quantities of fruits are left underexploited due to lack of scientific information on their chemical composition and nutritional potential. Here we report the nutritional properties of M. baccifera fruits and the ecological significance of its fruiting. This pear-shaped, fleshy bamboo fruit is rich in amino acids (lysine, glutamic acid), sugars (sucrose, glucose, fructose) and phenolics (ferulic acid). Protein content (free, bound) in M. baccifera fruits is very low. Fruits are rich in saturated fatty acids (palmitic acid), minerals (potassium) and only B series vitamins (B3) are detected in them. Rat feeding experiments showed that M. baccifera fruit alone is not a complete food, but with other protein supplements, it is a valuable food additive. This study could lead to better utilization of M. baccifera fruits during future flowering/fruiting events. These results could also help in the successful management of rodent outbreaks and other ecological problems associated with M. baccifera fruiting.

Mucuna pruriens is the best known natural source of L-dopa, the gold standard for treatment of Parkinsonism. M. pruriens varieties are protein rich supplements and are used as food and fodder worldwide. Here, we report L-dopa contents in seeds of fifty six accessions of four M. pruriens varieties, M. pruriens var. pruriens, M. pruriens var. hirsuta, M. pruriens var. utilis and M. pruriens var. thekkadiensis, quantified by HPTLC-densitometry. L-dopa contents varied between 0.58 to 6.42 (%, dr. wt.). High and low L-dopa yielding genotypes/chemotypes of M. pruriens could be multiplied for medicinal and nutritional purposes, respectively. HPTLC profiles of M. pruriens seeds on repeated extraction (24 h) in 1:1 formic acid-alcohol followed by development in butanol:acetic acid:water (4:1:1, v/v) showed consistent degradation of L-dopa (Rf 0.34 ± 0.02) into a second peak (Rf 0.41 ± 0.02). An average of 52.11% degradation of L-dopa was found in seeds of M. pruriens varieties. Since M. pruriens seeds and/or L-dopa are used for treatment of Parkinson’s disease and as an aphrodisiac both in modern and/or traditional systems of medicine, the finding of high level of L-dopa degradation (in pure form and in M. pruriens extracts) into damaging quinones and ROS is very significant.

Extrapulmonary manifestations constitute 15 to 20% of tuberculosis cases, with lymph node tuberculosis (LNTB) as the most common form of infection. However, diagnosis and treatment advances are hindered by lack of understanding of LNTB biology. To identify host response, Mycobacterium tuberculosis infected lymph nodes from LNTB patients were studied by means of transcriptomics and quantitative proteomics analyses. The selected targets obtained by comparative analyses were validated by quantitative PCR and immunohistochemistry. This approach provided expression data for 8,728 transcripts and 102 proteins, differentially regulated in the infected human lymph node. Enhanced inflammation with upregulation of T-helper1-related genes, combined with marked dysregulation of matrix metalloproteinases, indicates tissue damage due to high immunoactivity at infected niche. This expression signature was accompanied by significant upregulation of an immunoregulatory gene, leukotriene A4 hydrolase, at both transcript and protein levels. Comparative transcriptional analyses revealed LNTB-specific perturbations. In contrast to pulmonary TB-associated increase in lipid metabolism, genes involved in fatty-acid metabolism were found to be downregulated in LNTB suggesting differential lipid metabolic signature. This study investigates the tissue molecular signature of LNTB patients for the first time and presents findings that indicate the possible mechanism of disease pathology through dysregulation of inflammatory and tissue-repair processes.

Grasses are traditionally considered as wind pollinated, however, field observations confirmed frequent insect visits to grass flowers, suggesting insect pollination. Fruit and seed predators inflict heavy losses to cereals and millets during their growth, maturation and storage. The actual factors guiding insects and predators to grass flowers, fruits and seeds are not clear. Here, we report attractive blue fluorescence emissions on grass floral parts such as glumes, lemma, palea, lodicules, staminal filaments, pollens and fruits in ultraviolet (UV) 366 nm, whereas the stigmatic portions were not blue, but red fluorescent. We characterized the blue fluorescent constituent in grass reproductive structures as ferulic acid (FA). Fluorescence spectra of blue-emitting grass floral, seed extracts and isolated FA on excitation at 366 nm showed their emissions at 420–460 nm. We propose these FA-based blue fluorescence emissions in grass reproductive structures as visual cues that attract pollinators, predators and even pests towards them.