Chemico-nutritional characterization and anti-inflammatory potential of Chirabilva (Holoptelea integrifolia Roxb.) seed: alternate source of protein supplement and fatty acids.

Exploring unconventional protein sources can be an alternative strategy to meet the deficiency. The seeds of Chirabilva (Holoptelea integrifolia Roxb., Family- Ulmaceae) are eaten raw by the ethnic communities of Southeast Asian countries. The present study assessed the chemical, nutritional, and biological potential of the seeds (HIS) and pericarp (HISP) of H. integrifolia. The seeds contain mainly fixed and very few essential oils. The fixed oil of HIS is composed primarily of unsaturated oleic (47%) and saturated palmitic (37%) acids. The HIS are exceptional due to a high content of lipid (50%), protein (24%), carbohydrates (19%), fiber (4%), and anti-nutritional components within permissible limits. The high content (in mg/Kg) of phosphorus (6000), magnesium (422), Calcium (279), and essential nutrients (Ni, Co, Zn, Fe, Cu, Mn, and Cr) in the range of (0.04-6.69) were observed. The moderate anti-oxidant potential of HISP was evident in single electron transfer in-vitro assays. Moreover, HISP extract and HIS solvent-extracted fixed oil showed anti-inflammatory action in lipopolysaccharide-induced HaCaT cells by significantly attenuating pro-inflammatory cytokines (TNF-α) without causing cytotoxicity. Results support de-oiled HIS cake as an alternative source of a high-protein diet and its oil with anti-inflammatory attributes for topical applications.

Impact of cultivating different Ocimum species on bioaerosol bacterial communities and functional genome at an agricultural site.

The effects of the surrounding environment on the bacterial composition of bioaerosol were well documented for polluted and contaminated sites. However, there is limited data on the impact of plant species, especially those that produce aromas, on bioaerosol composition at agricultural sites. Hence, the aim of this study is to evaluate the variability in bacterial communities present in bioaerosol samples collected from agricultural sites with aroma-producing crops. For this, PM2.5, PM10, and bioaerosol samples were collected from agricultural fields growing Ocimum [two varieties of O. sanctum (CIM-Aayu and CIM-Angana)] and O. kilimandscharicum (Kapoor), nearby traffic junctions and suburban areas. PM2.5 and PM10 concentrations at the agricultural site were in between the other two polluted sites. However, bioaerosol concentration was lower at agricultural sites than at other sites. The culturable bacteria Bacillus subtilis, Bacillus tequilensis, and Staphylococcus saprophyticus were more prevalent in agricultural sites than in other areas. However, the composition of non-culturable bacteria varied between sites and differed in three fields where Ocimum was cultivated. The CIM-Aayu cultivated area showed a high bacterial richness, lower Simpson and Shannon indices, and a distinctive metabolic profile. The sites CIM-Angana and CIM-Kapoor had a higher abundance of Aeromonas, while Pantoea and Pseudomonas were present at CIM-Aayu. Acinetobacter, Staphylococcus, and Bacillus were the dominant genera at the other two sites. Metabolic profiling showed that the CIM-Aayu site had a higher prevalence of pathways related to amino acid and carbohydrate metabolism and environmental information processing compared to other sites. The composition of bioaerosol among the three different Ocimum sites could be due to variations in the plant volatile and cross-feeding nature of bacterial isolates, which further needs to be explored.

Development of amine-functionalized fluorescent silica nanoparticles from coal fly ash as a sustainable source for nanofertilizer.

Scaling up the synthesis of fluorescent silica nanoparticles to meet the current demand in diverse applications involves technological limitations. The present study relates to the hydrothermal synthesis of water-soluble, crystalline, blue-emitting amine-functionalized silica nanoparticles from coal fly ash sustainably and economically. This study used tertiary amine (trimethylamine) to prepare amine-functionalized fluorescent silica nanoparticles, enhancing fluorescence quantum yield and nitrogen content for nanofertilizer application. The TEM and FESEM studies show that the silica nanoparticles have a spherical morphology with an average diameter of 4.0 nm. The x-ray photoelectron and Fourier transform infrared spectroscopy studies reveal the presence of the amine group at the surface of silica nanoparticles. The silica nanoparticles exhibit blue fluorescence with an emission maximum of 454 nm at 370 nm excitation and show excitation-dependent emission properties in the aqueous medium. With the perfect spectral overlap between silica nanoparticle emission (donor) and chlorophyll absorption (acceptor), fluorescent silica nanoparticles enhance plant photosynthesis rate by resonance energy transfer. This process accelerates the photosynthesis rate to improve the individual plant's quality and growth. These findings suggested that the fly ash-derived functionalized silica nanoparticles could be employed as nanofertilizers and novel delivery agents.

Chemical and toxicological studies on black crust formed over historical monuments as a probable health hazard.

Studies to date have mostly investigated environmental factors responsible for deterioration of historical monuments. Black crusts formed on historical monuments are considered as factor for deterioration of structures or as an indicator of environmental status of the surrounding area. Black crust formed on historical monuments has never been investigated as a health hazard. Herein, for the first time, we performed in vitro and in vivo toxicology studies of black crust formed on three culturally-rich historical monuments (Rang Ghar, Kareng Ghar, and Talatal Ghar) of the Indian subcontinent to test their toxicological effect. Black crust suspension in ultrapure water was found not to be considerably toxic to the cells upon direct short-term exposure. However, the sub-acute nasal exposure of the black crust suspension in Swiss albino mice produced lung-specific pathologies and mortality. Additionally, structural formation of the black crust along with the speciation of potentially hazardous elements (PHEs), polyaromatic hydrocarbon (PAHs), and other metals were investigated. Overall, these results indicate the potential of black crust deposited on historical monuments as health hazard owing to the atmospheric pollution of the surroundings. However, it may be noted that black crust and its components have very low possibility of health implication unless they are disturbed without proper care.

Dissipation kinetics of chlorpyrifos and 3,5,6 trichloro-2-pyridinol under vegetation of different aromatic grasses: Linkage with enzyme kinetics and microbial community of soil.

The dissipation of chlorpyrifos (CP) and its hydrolytic metabolite 3,5,6-trichloro-2-pyridinol (TCP) in the soil is crucial for safe agriculture. However, there is still lacking relevant information about its dissipation under different vegetation for remediation purposes. In the present study, evaluation of dissipation of CP and TCP in non-planted and planted soil with different cultivars of three types of aromatic grass viz Cymbopogon martinii (Roxb. Wats), Cymbopogon flexuosus, and Chrysopogon zizaniodes (L.) Nash was examined in light of soil enzyme kinetics, microbial communities, and root exudation. Results revealed that the dissipation of CP was well-fitted into a single first-order exponential model (SFO). A significant reduction in the half-life (DT50) of CP was observed in planted soil (30-63 days) than in non-planted soil (95 days). The presence of TCP in all soil samples was observed. The three types of the inhibitory effect of CP i.e. linear mixed inhibition (increase in enzyme-substrate affinity (Km) and decrease in enzyme pool (Vmax), un-competitive inhibition (decrease in Km and Vmax), and simple competitive inhibition were observed on soil enzymes involved in mineralization of carbon, nitrogen, phosphorus, and sulfur. The improvement in the enzyme pool (Vmax) was observed in planted soil. Streptomyces, Clostridium, Kaistobacter, Planctomyces, and Bacillus were the dominant genera in CP stress soil. CP contamination in soil demonstrated a reduction of richness in microbial diversity and enhancement of functional gene family related to cellular process, metabolism, genetic, and environmental information processing. Among all the cultivars, C. flexuosus cultivars demonstrated a higher dissipation rate of CP along with more root exudation.

Anthropogenic aerosols in precipitation over the Indo-Gangetic basin.

This study investigated the concentration of heavy metals in rainwater (RW) at a semi-arid region of the Indo-Gangetic basin to understand the influence of local, regional, or long-range transport of air pollutants during the monsoon and non-monsoonal rain. The concentration of heavy metals in RW was determined using Atomic Absorption Spectrophotometer with Graphite Furnace, the scavenging ratio was estimated, and source interpretation was carried out using Principle Component Analysis (PCA) and HYSPLIT model. Ca was the highest contributor in RW followed by Na, Fe, Mg, and Al whereas Ba, Cr, Cu, Mn, Ni, Pb, and Zn were found in trace quantity. During the non-monsoon period, the crustal component (Ca) was the highest; however, during the monsoon, sea salt components (Na and Fe) were found higher. The scavenging ratio for metals was estimated and was found many times higher than those reported over European sites. The moderate concentration of heavy metal in RW was found with higher wind from South (S), South-West (SW), and North-West (NW) directions. Air mass back trajectory shows a significant contribution of metals from the Arabian Sea (South-Westerly wind) during active monsoon, whereas, in the non-monsoon season, the air masses mainly originated from the north-west indicating a contribution from wind-blown dust. The correlation analysis has shown the positive correlations between Ca and Mg, Mg and Na, Na and Cu, Al and Zn, Zn and Ba, Ba and Cr, and Cr and Zn. Principal Component Analysis (PCA) indicated loading of Ca, Na, Mg, Cu, Mn, and Ni in the first factor suggesting their crustal origin, whereas the second factor showed high loading of Al, Ba, Zn, Cr, and Ni indicating vehicular exhaust and industrial emission as their major sources, and loading for Ba and Mg in the third factor indicates the mixed contribution from both natural and anthropogenic sources in rainwater during the monsoon and non-monsoon periods. The data of this study can be used in the air pollution transport model. This study will help in source interpretation over the Indo-Gangetic basin and will help in planning for National Clean Air Program (NCAP) and deriving critical load.

Assessment of soil enzymatic resilience in chlorpyrifos contaminated soils by biochar aided Pelargonium graveolens L. plantation.

Chlorpyrifos (CP), a broad-spectrum organophosphorus insecticide, is known for deleterious effects on soil enzymatic activities. Hence, the present study aims to examine the resilience effect of biochar (BC) aided Pelargonium graveolens L. plantation on enzymatic activities of chlorpyrifos contaminated soil. The two chlorpyrifos contaminated agriculture soils (with concentrations: S1: 46.1 and S2: 95.5 mg kg-1) were taken for the pot experiment. The plant biomass, plant growth parameters, soil microbial biomass, and enzymatic activities such as alkaline phosphatase, N-acetyl glucosaminidase, aryl sulphatase, cellulase, ß-glucosidase, dehydrogenase, phenoloxidase, and peroxidase enzymes were  examined. Ecoenzyme activities and their stoichiometry were used to enumerate the different indices including geometric mean, weighted mean, biochemical activity indices, integrated biological response, treated-soil quality index, and vector analysis in all treatments. The results of the study demonstrated that the biochar incorporation enhanced the tolerance of P. graveolens (from 42-45% to 55-67%) in chlorpyrifos contaminated soil and reduced the CP accumulation in plants. A reduction in the inhibitory effect of chlorpyrifos on soil enzymatic activities and plant growth by BC incorporation was observed along with an increase in the activities of ecoenzymes (16.7-18.6%) in soil. The investigation indicated more microbial investments in C and P than that in N acquisition under CP stress. The BC amendment catalyzed the activities of lignin and cellulose-degrading enzymes and enhanced nutrition acquisition. The CP contamination and BC amendment have no significant effect on the oil quality of P. graveolens. The study demonstrated that BC-aided P. graveolens plantation offers sustainable phytotechnology for CP contaminated soil with an economic return.

Melatonin Attenuates Extracellular Matrix Accumulation and Cardiac Injury Manifested by Copper.

Copper-induced cardiac injury is not widely reported in spite of its ability to cause oxidative damage and tissue injury. Structural and morphological changes in the cardiac tissue are triggered via oxidative stress and inflammatory responses following copper exposure. The varied and unavoidable exposure of copper through contaminated food and water warrants a safe and effective agent against its harmful effects. Since the heart is highly sensitive to changes in the redox balance, the present study was undertaken to examine the protective effects of melatonin against copper-induced cardiac injury. Sprague Dawley (SD) rats were exposed to 100 ppm of elemental copper via drinking water for 4 months. The cardiac tissue was evaluated for various biochemical, histological, and protein expression studies. Animals exposed to copper exhibited induced oxidative stress and cardiac injury compared to normal control. To this end, we found that melatonin treatment ameliorated copper-induced alterations in tissue oxidative variables like ROS, nitrate, MDA, and GSH. In addition, histological examinations unravelled decreased cardiac muscle dilation, atrophy, and cardiomyopathy in melatonin-treated rats. Furthermore, melatonin-treated rats were associated with reduced tissue copper levels, collagen deposition, α-SMA, and increased HO-1 expression as compared to rats exposed exclusively to copper. Moreover, the levels of NF-κB and cardiac markers such as CK-MB, cTnI, and cTnT were found to be decreased in the melatonin-treated animals. Altogether, melatonin-triggered increase in antioxidant capacity resulting in reduced aggregation of ECM components demonstrates the therapeutic potential of melatonin in the treatment of cardiac injury and tissue fibrosis.

Insights into the effects of tea pruning litter biochar on major micronutrients (Cu, Mn, and Zn) pathway from soil to tea plant: An environmental armour.

A field study was conducted from 0 to 360 days to investigate the effect of tea pruning litter biochar (TPLBC) on the accumulation of major micronutrients (copper: Cu, manganese: Mn, and zinc: Zn) in soil, their uptake by tea plant (clone: S.3 A/3) and level of contamination in soil due to TPLBC. To evaluate the level of contamination due to TPLBC, a soil pollution assessment was carried out using the geo-accumulation index (Igeo), enrichment factor (EF), contamination factor (CF), potential ecological risk factor (PERF), individual contamination factor (ICF), and risk assessment code (RAC). The total content of Cu, Mn, and Zn gradually increased with increasing doses of TPLBC at 0D, and then decreased with time. The fractionation of the three micronutrients in soil changed after the application of TPLBC. The contamination risk assessment of soil for Cu, Mn, and Zn based on the Igeo, EF, CF, PERF,ICF, and RAC suggested that the application of TPLBC does not have any adverse effect on soil. Except for Mn, the bioconcentration and translocation factors were less than one for Cu and Zn. Results from this study revealed that the application of 400 kg TPLBC ha-1 is significantly better than the other treatments for Cu, Mn, and Zn at a 5% level of significance.

Towards the development of phytoextract based healthy ageing cognitive booster formulation, explored through Caenorhabditis elegans model.

The positive effect of herbal supplements on aging and age-related disorders has led to the evolution of natural curatives for remedial neurodegenerative diseases in humans. The advancement in aging is exceedingly linked to oxidative stress. Enhanced oxidative stress interrupts health of humans in various ways, necessitating to find stress alleviating herbal resources. Currently, minimal scientifically validated health and cognitive booster resources are available. Therefore, we explored the impact of plant extracts in different combinations on oxidative stress, life span and cognition using the multicellular transgenic humanized C. elegans, and further validated the same in Mus musculus, besides testing their safety and toxicity. In our investigations, the final product-the HACBF (healthy ageing cognitive booster formulation) thus developed was found to reduce major aging biomarkers like lipofuscin, protein carbonyl, lipid levels and enhanced activity of antioxidant enzymes. Further confirmation was done using transgenic worms and RT-PCR. The cognitive boosting activities analyzed in C. elegans and M. musculus model system were found to be at par with donepezil and L-dopa, the two drugs which are commonly used to treat Parkinson's and Alzheimer's diseases. In the transgenic C. elegans model system, the HACBF exhibited reduced aggregation of misfolded disease proteins α-synuclein and increased the health of nicotinic acetylcholine receptor, levels of Acetylcholine and Dopamine contents respectively, the major neurotransmitters responsible for memory, language, learning behavior and movement. Molecular studies clearly indicate that HACBF upregulated major genes responsible for healthy aging and cognitive booster activities in C. elegans and as well as in M. musculus. As such, the present herbal product thus developed may be quite useful for healthy aging and cognitive boosting activities, and more so during this covid-19 pandemic. Supplementary Information: The online version contains supplementary material available at 10.1007/s13237-022-00407-1.

Tea pruning litter biochar amendment in soil reduces arsenic, cadmium, and chromium in made tea (Camellia sinensis L.) and tea infusion: A safe drink for tea consumers.

Effect of tea pruning litter biochar (TPLBC) on arsenic (As), cadmium (Cd) and chromium (Cr) content in made tea and successive tea infusions were investigated in a greenhouse experiment with two tea cultivars (TV23 and S.3A/3). Made tea prepared from TV23 and S.3A/3 clone, a decrease in the concentration of As, Cd, and Cr by 36.73%, 16.22%, 13.96%, and 36.63%, 27.78%, 10.54%, respectively over control on the application of the highest dose of TPLBC (500 kg TPLBC ha-1). Irrespective of treatments, studied element concentrations were significantly higher (p ≤ 0.05) in the first infusion and lower in the third. Considering Ten g made tea consumption per person per day, the maximum average daily intakes of As, Cd and Cr in a higher dose of TPLBC were far below the tolerable weekly intake prescribed by the World Health Organization. As hazard quotient values of selected elements were ≪ 1, no significant adverse health consequences are expected for tea consumers.

Ameliorative effects of biochar on persistency, dissipation, and toxicity of atrazine in three contrasting soils.

The presence of atrazine a persistent herbicide in soil poses a serious threat to the ecosystem. The biochar amendment in soil altered the fate of this herbicide by modifying the soil properties. The present study examines the dissipation and toxicity of atrazine in three contrasting soils (silty clay, sandy loam, and sandy clay) without and with biochar amendment (4%). The experiment was performed for 150 days with three application rates of atrazine (4, 8, and 10 mg kg-1). The speciation and degradation of atrazine, metabolite content, microbial biomass, and enzymatic activities were evaluated in all treatments. Three kinetic models and soil enzyme index were calculated to scrutinize the degradation of atrazine and its toxicity on soil biota, respectively. The goodness of fit statistical indices suggested that the first-order double exponential decay (FODE) model best described the degradation of atrazine in silty clay soil. However, a single first order with plateau (SFOP) was best fitted for atrazine degradation in sandy loam and sandy clay soils. The half-life of atrazine was higher in sandy clay soil (27-106 day-1) than silty clay (28-77 day-1) and sandy loam soil (27-83 day-1). The variations in the dissipation kinetics and half-life of the atrazine in three soil were associated with atrazine partitioning, availability of mineral content (silica, aluminum, and iron), and soil microbial biomass carbon. Biochar amendment significantly reduced the plateau in the kinetic curve and also reduced the atrazine toxicity on soil microbiota. Overall, biochar was more effective in sandy clay soil for the restoration of soil microbial activities under atrazine stress due to modulation in the pH and more improved soil quality.

Novel approach for harvesting of microalgal biomass using electric geyser waste material deposit as flocculant in coupling with poultry excreta leachate.

The aim of this work was to study the flocculation efficiency of algal biomass (Chlorella pyrenoidosa) in coupling with waste materials i.e. poultry excreta leachate by using other waste material which was obtained from deposition of scaling in electric geyser. Utilization of electric geyser waste material deposit (EGWMD) for flocculation is a novel approach because of various elements which are replica of chemical flocculants responsible for flocculation mechanism in culture medium. Flocculation process was optimized by response surface methodology and 98.21% flocculation efficiency was achieved with designed process parameters as temperature 32.5 °C, flocculant dose 275 mgL-1, pH 5 and time 30 min. The reusability of spent medium was also analyzed at 70.2% and 32.5% flocculation efficiency with two successive steps. The cellular morphology of pre-harvested and post-harvested Chlorella pyrenoidosa was also observed. EGWMD is abundant and freely available that has no application till now and can alternate of chemical flocculants.

Endophytic bacterium CIMAP-A7 mediated amelioration of atrazine induced phyto-toxicity in Andrographis paniculata.

The presence of atrazine, a triazine herbicide, and its residues in agriculture soil poses a serious threat to human health and environment through accumulation in edible plant parts. Hence, the present study focused on atrazine induced stress amelioration of Andrographis paniculata, an important medicinal plant, by a plant growth promoting and atrazine degrading endophytic bacterium CIMAP-A7 inoculation. Atrazine has a non-significant effect at a lower dose while at a higher dose (lower: 25 and higher: 50 mg kg-1) 22 and 36% decrease in secondary metabolite content and plant dry weight of A. paniculata was recorded, respectively. Endophyte CIMAP-A7 inoculation significantly reduced atrazine soil content, by 78 and 51% at lower and a higher doses respectively, than their respective control treatments. Inoculation of CIMAP-A7 exhibited better plant growth in terms of increased total chlorophyll, carotenoid, protein, and metabolite content with reduced atrazine content under both atrazine contaminated and un-contaminated treatments. Atrazine induced oxidative stress in A. paniculata was also ameliorated by CIMAP-A7 by reducing stress enzymes, proline, and malondialdehyde accumulation under contaminated soil conditions than un-inoculated treatments. Furthermore, the presence of atrazine metabolites deisopropylatrazine (DIA) and desethylatrazine (DEA) strongly suggests a role of CIMAP-A7 in mineralization however, the absence of these metabolites in uninoculated soil and all plant samples were recorded. These findings advocate that the amelioration of atrazine induced stress with no/least pesticide content in plant tissues by plant-endophyte co-interactions would be efficient in the remediation of atrazine contaminated soils and ensure safe crop produce.

The incorporation of lemongrass oil into chitosan-nanocellulose composite for bioaerosol reduction in indoor air.

The bioaerosols present in indoor air play a major role in the transmission of infectious diseases to humans, therefore concern about their exposure is increased recently. In this regard, the present investigation described the preparation of lemongrass essential oil (LGEO) loaded chitosan and cellulose nanofibers composites (CH/CNF) for controlling the indoor air bioaerosol. The evaluation of the inhibitory effect of the composite system on culturable bacteria of the indoor air was done at different sites (air volume from 30 m3 to 80 m3) and in different size fractions of aerosol (<0.25 µm-2.5 µm). The composite system had high encapsulation efficiency (88-91%) and citrals content. A significant reduction in culturable bacteria of aerosol (from 6.23 log CFUm-3 to 2.33 log CFUm-3) was observed in presence of cellulose nanofibers and chitosan composites. The bacterial strains such as Staphylococcus sp., Bacillus cereus, Bacillus pseudomycoides sp., Pseudomonas otitidis, and Pseudomonas sp. Cf0-3 in bioaerosols were inhibited dominantly due to the diffusion of aroma molecules in indoor air. The results indicate that the interaction of diffused aroma molecule from the composite system with bacterial strains enhanced the production of ROS, resulting in loss of membrane integrity of bacterial cells. Among different size fractions of aerosol, the composite system was more effective in finer size fractions (<0.25 µm) of aerosol due to the interaction of smaller aroma compounds with bacterial cells. The study revealed that LGEO loaded chitosan and cellulose nanofibers composites could be a good option for controlling the culturable bacteria even in small-sized respirable bioaerosol.

Biochar amendment reduced the risk associated with metal uptake and improved metabolite content in medicinal herbs.

Contaminations of heavy metals such as lead (Pb) and cadmium (Cd) in medicinal plants (MPs) not only restrict their safe consumption due to health hazards but also lower their productivity. Biochar amendments in the soil are supposed to immobilize the toxic metals, improve the soil quality and agricultural productivity. However, the impact of biochar on growth attributes, metal accumulation, pharmacologically active compounds of MPs, and health risk is less explored. An experiment was performed on three medicinal plants (Bacopa monnieri (L.), Andrographis paniculata (Burmf.) Nees, and Withaniasomnifera (L.)) grown in a greenhouse in soil co-contaminated with Pb and Cd (at two concentrations) without and with biochar amendments (2 and 4% application rates). The fractionation of Pb and Cd, plant growth parameters, stress enzymes, photosynthetic capacity, pharmacologically active compounds, nutrient content, uptake and translocation of metals, antioxidant activities, and metabolite content were examined in the three MPs. The accumulation of Pb and Cd varied from 3.25-228 mg kg1 and 1.29-20.2 mg kg-1 , respectively, in the three MPs, while it was reduced to 0.08-18 mg kg-1 and 0.03-6.05 mg kg-1 upon biochar treatments. Plants grown in Pb and Cd co-contaminated soil had reduced plant biomass (5-50% depending on the species) compared to control and a deleterious effect on photosynthetic attributes and protein content. However, biochar amendments significantly improved plant biomass (21-175%), as well as photosynthesis attributes, chlorophyll, and protein contents. Biochar amendments in Pb and Cd co-contaminated soil significantly reduced the health hazard quotient (HQ) estimated for the consumption of these medicinal herbs grown on metal-rich soil. An enhancement in secondary metabolite content and antioxidant properties was also observed upon biochar treatments. These multiple beneficial effects of biochar supplementation in Pb and Cd co-contaminated soil suggested that a biochar amendment is a sustainable approach for the safe cultivation of MPs. This article is protected by copyright. All rights reserved.

Arsenic-induced differential expression of oxidative stress and secondary metabolite content in two genotypes of Andrographis paniculata.

The present study explores the differential responses of two genotypes (APwC: wild collection and APMS: mass selection line) of A. paniculata against the three application rates of arsenic (42, 126, and 200 mg kg-1). The oxidative enzymes, As accumulation in different tissues, plant growth, and content of pharmacologically important ent-labdane-related diterpenes (ent-LRDs) of the two genotypes were evaluated in the study. Results demonstrated that As uptake significantly reduced plant biomass in APwC and APMS by 5-41.5% and 9-33% in a dose-response manner, respectively. The APMS exhibited lower bioconcentration and translocation factors, higher As tolerance index, and higher content of ent-LRDs as compared to APWC. As treatment induced a decrease in the sum of four metabolite content of APMS (1.43 times) and an increase in that of APWC (1.12 times) as compared to control. Likewise, variance in the production of 5,7,2',3'-tetramethoxyflavanone, and stress enzymes was also observed between APwC and APMS. The increase in the expression of ApCPS2 suggested its involvement in channeling of metabolic flux towards the biosynthesis of ent-LRDs under As stress.

Temperature effect on biochar produced from tea (Camellia sinensis L.) pruning litters: A comprehensive treatise on physico-chemical and statistical approaches.

The present study aimed to optimize the production of biochar from tea (Camellia sinensis L.) pruning litter. Characterization of biochar prepared from four tea pruning litters (mixed, Tocklai Vegetative 1, 22 and 25) at five pyrolysis temperatures (250, 300, 350, 400, 450, and 500 °C for 3 h) were documented. The results demonstrated that yield, total nitrogen, H:C, and O:C decreased steadily with increasing pyrolysis temperature. However, water holding capacity, ash content, fixed carbon, C:N, NH4+-N, NO3--N, trace elements, total P and K, and germination index increased consistently with increasing pyrolysis temperature. All the prepared biochars are suitable for agriculture application as H:C and O:C ratios of prepared biochars are <0.6 and <0.4, respectively. Low pyrolysis temperature (<300 °C) was optimal to get more stable biochar with respect to essential nutrients. Biochar derived from Tocklai Vegetative 1 at 300 °C has more potential for agronomic applications. Principal component analysis showed >96% variability.

Yeast strain Debaryomyces hansenii for amelioration of arsenic stress in rice.

Arsenic (As) is a serious threat for environment and human health. Rice, the main staple crop is more prone to As uptake. Bioremediation strategies with heavy metal tolerant rhizobacteria are well known. The main objective of the study was to characterize arsenic-resistant yeast strains, capable of mitigating arsenic stress in rice. Three yeast strains identified as Debaryomyces hansenii (NBRI-Sh2.11), Candida tropicalis (NBRI-B3.4) and Candida dubliniensis (NBRI-3.5) were found to have As reductase activity. D. hansenii with higher As tolerance has As expulsion ability as compared to other two strains. Inoculation of D. hansenii showed improved detoxification through scavenging of reactive oxygen species (ROS) by the modulation of SOD and APX activity under As stress condition in rice. Modulation of defense responsive gene (NADPH, GST, GR) along with arsR and metal cation transporter are the probable mechanism of As detoxification as evident with improved membrane (electrolyte leakage) stability. Reduced grain As (~40% reduction) due to interaction with D. hansenii (NBRI-Sh2.11) further validated it's As mitigation property in rice. To the best of our knowledge D. hansenii has been reported for the first time for arsenic stress mitigation in rice with improved growth and nutrient status of the plant.

Bioremediation of arsenic by soil methylating fungi: Role of Humicola sp. strain 2WS1 in amelioration of arsenic phytotoxicity in Bacopa monnieri L.

Fungi mediated arsenic (As) stress modulation has emerged as an important strategy for the mitigation of As mediated stress management in plants for reducing As contamination to the food chain. In the present study, total of 45 fungal strains were isolated from the three As contaminated sites of West Bengal, India. These strains were morphologically different and inhibited variable As tolerance (10 to 5000 mg l-1As). Total 21 fungal isolates, tolerant up to 5000 mg l-1 AsV, were investigated for As removal (10 mg l-1 As) after 21 d of cultivation under laboratory conditions. The As bioaccumulation in fungal biomass ranged between 0.146 to 11.36 g kg-1 biomass. Range of volatilized As was between 0.05 to 53.39 mg kg-1 biomass. Most promising bioaccumulation and biovolatilization potential were observed in strains viz., 2WS1, 3WS1 and 2WS9. Strain 2WS1 showed highest As biovolatilization (53.39 mg kg-1 biomass) and was identified as Humicola sp. using ITS/5.8S rDNA gene sequencing. This is the first report of Humicola sp. having As biomethylation property. Best first 8 As biomethylating fungal strains were further tested for their As remediation and PGP potential in Bacopa monnieri plant grown in As contaminated soil (20 mg kg-1) in a pot experiment under greenhouse conditions. The highest leaf stem ratio and lowest As content in leaf tissues were observed in 2WS1 inoculated Bacopa monnieri plants. The presence of arsM gene in 2WS1 strain suggests As biovolatilization as possible bioremediation and As stress mitigation strategy of 2WS1. Therefore, application of this strain of Humicola sp. strain 2WS1 in As contaminated soils could be a potential and realistic mitigation strategy for reducing As contamination to cropping system coupled with enhanced productivity.