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Leguminous shade trees are ubiquitous parts of tea plantations of the Terai region. However, their shed leaves might have an effect on the soil microflora under those shade trees, so it is important to find out how leaf litter affect the soil microflora. Isolation of soil microbial consortia followed by downstream experiments were conducted to observe the tolerance/susceptible pattern of those soil microflora against the fallen leaves. Sample from under Albizia odoratissima has higher organic carbon, organic matter and nitrogen content but the same property was found to be low in the sample collected under Melia azedarach. Isolation of consortia was done on nutrient agar. In vitro tolerance assay was conducted to find out the tolerance pattern against leaf extracts, heavy metal salts, pesticides, antibiotics and antifungals. Heavy metals salts like Arsenic trioxide (AS2O3) and Cupric chloride (CuCl2); and pesticides like Thiamethoxam; Spiromesifen; Phorate etc. showed no inhibition against all the isolated consortia. Co-Trimoxazole and Augmentin have not showed any inhibition except consortia under Derris robusta, whereas no antifungals but Itraconazole had an impact over all the consortia. Shade trees, being a crucial member of the tea plantations, cannot be removed but replacement of these with other species could be a probable option, besides this limited use of chemical pesticides and fertilizers should be taken into consideration strictly to restrain the microbial population in tea garden soil. So, this study has disclosed the acceptability of each and every shade tree used in this region.

Abstract Background The tea plant, Camellia sinensis (L.) O. Kuntze, is an evergreen leafy plant whose tender leaves are used in the manufacturing of the world’s second most consumed beverage—tea. The production and consumption of tea worldwide have continually increased over the decades. All parts of the plant—leaf, stem, root, flower and seed, are fed upon by insect pests. This study elucidates the metabolomic changes occurring in tea leaves in response to infestation by two major pests in tea gardens: red spider mites and tea mosquito bugs. These pests significantly impact both the quantity and quality of tea production. The secondary metabolites produced by the tea due to pest attack has been analysed using GC–MS analysis in the laboratory. Results Mostly fatty acid derivatives were biosynthesized as secondary metabolites due to pest attack as revealed from the result. In both infestations, methyl stearate was found to be produced along with increased chromatographic peaks of compounds such as caffeine, methyl palmitate, methyl linoleate, and stigmasta-7,25-dien-3-ol. In comparison with respective control samples (leaf with no pest attack), the one attacked by red spider mite showed eighteen exclusive metabolites, whereas tea mosquito bug infested leaf showed six such exclusive metabolites. Conclusions Some metabolites were found to be either increased or decreased in their amount in both the samples. The increased compounds were reported with insecticidal and pesticidal properties with respect to respective controls. Some metabolites were markers of pest attacks i.e. plant defense mechanism induced phytochemicals according to the literature as discussed in this research.

Abstract Tongba, chhyang, nigar and raksi are popular traditional drinks served in Nepal, northern and north eastern part of India and Tibetan plateau which are claimed as medicinal and considered as elements of high altitude ethnopharmacology. In this research, kodo (finger millet) based traditional beverages such as tongba, chhyang, nigar and raksi samples, collected from Singalila ridge of the Himalayas, were analysed through various qualitative and quantitative biochemical parameters. Total phenolic content (gallic acid equivalent) was estimated in a varied range from 936.26 ± 6.87 µg/mL (nigar) to 96.36 ± 1.22 µg/mL (chimphing raksi) while highest free fatty acid was measured in khokim raksi (2.11%). Antioxidant activity was evaluated using in vitro assays (DPPH assay, iodometric assay and in vitro anti-lipid peroxidation assay); antibacterial assay was conducted using well diffusion method. Tongba was found to be the most potential sample in antioxidant assays with a DPPH scavenging value of 85.31 ± 1.54% while nigar was the sample with most promising antibacterial activity. Furthermore, special emphasis was given on GC-MS based metabolite profiling and metabolomic elucidation. Responsible candidates detected by GC-MS analysis were discussed to correlate results of preliminary biochemical screenings and in vitro bioactivities. In vitro gastrointestinal digestion was carried out to figure out bioaccessibility of the bioactive groups of compounds in simulated human GI tract where DPPH assay, total phenol content and lipid composition (acid value) were considered as parameters. Most of the bioavailable bioactive antioxidants and phenolics were estimated to be decreased in the gastric phase reflecting the highest rate of digestion in the stomach while breakdown of lipid composition was dominated by the intestinal phase. Overall results suggest that antioxidative phenolics and fatty acids from these beverages possess bioactivities in their bioavailable form which may be associated to their ethnomedicinal properties. Graphical Abstract

2D nanosheets produced using liquid phase exfoliation method offers scalable and cost effective routes to optoelectronics devices. But this technique sometimes yields high defect, low stability, and compromised electronic properties. In this work, we employed an innovative approach that improved the existing liquid phase exfoliation method for fabricating MoS2/graphene heterostructure-based photodetector with enhanced optoelectronic properties. This technique involves hydrothermally treating MoS2 before dispersing it in a carefully chosen and environmentally friendly IPA/water solvent for ultrasonication exfoliation through an optomechanical approach. Thereafter, heterostructure nanosheets of MoS2 and graphene were formed through sequential deposition technique for the fabrication of vertical heterojunctions. Furthermore, we achieved a vertically stacked MoS2/graphene photodetector and a bare MoS2 photodetector. The MoS2/graphene hybrid nanosheets were characterized using spectroscopic and microscopic techniques. The results obtained show the size of the nanosheets is between 350 and 500 nm on average, and their thickness is less than or equal to 5 nm, and high crystallinity in the 2H semiconducting phase. The photocurrent, photoresponsivity, external quantum efficiency (EQE), and specific detectivity of MoS2/graphene heterostructure at 4 V bias voltage and 650 nm illumination wavelength were 3.55 μA, 39.44 mA/W, 7.54 %, and 2.02 × 1010 Jones, respectively, and that of MoS2 photodetector are 0.55 μA, 6.11 mA/W, 1.16 %, and 3.4 × 109 Jones. The results presented indicate that the photoresponse performances of the as-prepared MoS2/graphene were greatly improved (about 7-fold) compared to the photoresponse of the sole MoS2. Again, the MoS2/graphene heterostructure fabricated in this work show better optoelectronic characteristics as compared to the similar heterostructure prepared using the conventional solution processed method. The results provide a modest, inexpensive, and efficient method to fabricate heterojunctions with improved optoelectronic performance.

Oxidative burden plays a central role in Alzheimer’s disease (AD) pathology, fostering protein aggregation, inflammation, mitochondrial impairment, and cellular dysfunction that collectively lead to neuronal injury. The role of exosomes in propagating the pathology of neurodegenerative diseases including AD is now well established. However, recent studies have also shown that exosomes are crucial responders to oxidative stress in different tissues. Thus, this offers new insights and mechanistic links within the complex pathogenesis of AD through the involvement of oxidative stress and exosomes. Several studies have indicated that exosomes, acting as intracellular communicators, disseminate oxidatively modified contents from one cell to another, propagating the pathology of AD. Another emerging aspect is the exosome-mediated inhibition of ferroptosis in multiple tissues under different conditions which may have a role in neurodegenerative diseases as well. Apart from their involvement in the pathogenesis of AD, exosomes enter the bloodstream serving as novel noninvasive biomarkers for AD; some of the exosome contents also reflect the cerebral oxidative stress in this disease condition. This review highlights the intricate interplay between oxidative stress and exosome dynamics and underscores the potential of exosomes as a novel tool in AD diagnosis.

Lafora disease (LD) is a syndrome of progressive myoclonic epilepsy and cumulative neurocognitive deterioration caused by recessively inherited genetic lesions of EPM2A (laforin) or NHLRC1 (malin). Neuropsychiatric symptomatology in LD is thought to be directly downstream of neuronal and astrocytic polyglucosan aggregates, termed Lafora bodies (LBs), which faithfully accumulate in an age‐dependent manner in all mouse models of LD. In this study, we applied home‐cage monitoring to examine the extent of neurobehavioral deterioration in a model of malin‐deficient LD as a means to identify robust preclinical endpoints that may guide the selection of novel genetic treatments. At 6 weeks, ∼6–7 months, and ∼12 months of age, malin‐deficient mice ("KO") and wild‐type (WT) littermates underwent a standardized home‐cage behavioral assessment designed to non‐obtrusively appraise features of rest/arousal, consumptive behaviors, risk aversion, and voluntary wheel‐running. At all timepoints, and over a range of metrics that we report transparently, WT and KO mice were essentially indistinguishable. In contrast, within WT mice compared across the same timepoints, we identified age‐related nocturnal hypoactivity, diminished sucrose preference, and reduced wheel‐running. Neuropathological examinations in subsets of the same mice revealed expected age‐dependent LB accumulation, gliosis, and microglial activation in cortical and subcortical brain regions. At 12 months of age, despite the burden of neocortical LBs, we did not identify spontaneous seizures during an electroencephalographic (EEG) survey, and KO and WT mice exhibited similar spectral EEG features. However, in an in vitro assay of neocortical function, paroxysmal bursts of network activity (UP states) in KO slices were more prolonged at 3 and 6 months of age, but similar to WT at 12 months. KO mice displayed a distinct response to pentylenetetrazole, with a greater incidence of clonic seizures and a more pronounced postictal suppression of movement, feeding, and drinking behavior. Together, these results highlight the clinicopathologic dissociation in a mouse model of LD, where the accrual of LBs may latently modify cortical circuit function and seizure threshold without clinically meaningful changes in home‐cage behavior. Our findings allude to a delay between LB accumulation and neurobehavioral decline in LD: one that may provide a window for treatment, and whose precise duration may be difficult to ascertain within the typical lifespan of a laboratory mouse. [ABSTRACT FROM AUTHOR]