In Silico Characterization of Pectate Lyase Protein Sequences from Different Source Organisms

A total of 121 protein sequences of pectate lyases were subjected to homology search, multiple sequence alignment, phylogenetic tree construction, and motif analysis. The phylogenetic tree constructed revealed different clusters based on different source organisms representing bacterial, fungal, plant, and nematode pectate lyases. The multiple accessions of bacterial, fungal, nematode, and plant pectate lyase protein sequences were placed closely revealing a sequence level similarity. The multiple sequence alignment of these pectate lyase protein sequences from different source organisms showed conserved regions at different stretches with maximum homology from amino acid residues 439–467, 715–816, and 829–910 which could be used for designing degenerate primers or probes specific for pectate lyases. The motif analysis revealed a conserved Pec_Lyase_C domain uniformly observed in all pectate lyases irrespective of variable sources suggesting its possible role in structural and enzymatic functions

Efficacy of Three Different Plant Species for Arsenic Phytoextraction from Hydroponic System

Abstract Arsenic (As) is one of the heavy metals which causes acute bio-toxicity even at low concentration and has disastrous effect on environment. In some countries, As contamination has become alarming and increasing day by day as consequences of unsustainable management practices. Many existing physical, chemical and biological processes for As removal from water system are not feasible due to techno-economic limitations. The present study highlights the scope of biological strategy for As removal through phytoextraction. Arsenic uptake and accumulation in the biomass of three plant species and their As tolerance abilities have been investigated to develop an efficient phytoextraction system in combination of these plant species. Three non-crop plant species, Pteris vittata; Mimosa pudica, and Eichhornia crassipus were treated with 0-200 mg/L As in liquid nutrient solution for 14 days. P. vittata accumulated total 9,082.2 mg (8,223 mg in fronds) As/kg biomass and Eichhornia total 6,969 mg (4,517 mg in fronds)/kg biomass at 200 mg/L As concentration, respectively. Bioaccumulation factor (BF) and translocation factor (TF) were estimated to differentiate between excluders, accumulators and accumulation in above ground biomass. Pteris and Eichhornia have highest BF (67 and 17) and TF (64 and 3), respectively. In contrast, Mimosa accumulated up to 174 mg As/kg plant biomass which is low in comparison with other two plants, and both BF and TF were ≤1. This study reveals that Pteris and Eichhornia are As hyperaccumulator, and potential candidates for As removal from water system

Enhancement of indigo dye yield from Indigofera plant biomass by using fungal elicitors during fermentation

619-624Natural indigo dye from biogenic materials is an alternative to synthetic indigo that pollutes the environment. Indigo production from the Indigofera tinctoria plant is in practice since ancient time through biomass fermentation in water. Maximum indigo yield depends on complete release of indigo precursor indican from plant biomass during fermentation. In this study, we assessed the role of fungal elicitors on indigo dye yield during biomass fermentation using three strains namely; Aspergillus niger, Trichoderma reesei and Sclerotium rolfsii. Fungal extracts were prepared from fungal mycelia, raised separately on Potato Dextrose agar medium and extracted in a buffer solution containing 1N HNO3 plus 1N NaOH. The extracts were added to fermentation water in 1, 5 and 10% doses (v/v) separately during biomass fermentation keeping other parameters for fermentation and further processing for dye production fixed. Indigo yield with 10% A. niger extract was 1.56% (w/w), which was higher in comparison to control 0.45% (w/w). A. niger extract at 10% enhanced indigo yield up to 3.5 times compared to control, and 2.7 and 2.1 times, respectively to other two cultures [T. reesei (0.58% w/w) and S. rolfsii (0.93% w/w)] used at the same concentration

Heavy metal (Pb) accumulation in metallophytes as influenced by the variations in rhizospheric and non-rhizospheric soils physico-chemical characteristics

Activities at root-soil interface determine the solubility and uptake of metals by plants. Metal accumulation in plant species (Imperata cylindrical, Cynodon dactylon, Eleucine indica, Gomphrena celosoides, Sporobolus pyramidalis, Chromolaena odorata and Rhynchospora corymbosa) growing on Pb contaminated site as influenced by variations in physico-chemical characteristics, dissolved organic matter (DOM), Pb fractionation and different functional groups (using Fourier Transmittance Infra-red) of rhizospheric and non-rhizospheric soils was assessed. The electrical conductivity (2660–5520 ms) and Pb concentrations (51390.0–64080.0 mg/kg) were more in non-rhizospheric than rhizospheric soils having 276 ms to 3160 ms EC and 3289.0 to 44850.0 mg/kg Pb. More nutrients, DOM and carbohydrates functional groups (C-O; 1100 -1000 and O-H; 3700–3600) were found in rhizospheric compared to non-rhizospheric soils. The pH was slightly acidic (5.0–5.54) and E. indica with the lowest pH (5.0) accumulated highest Pb concentrations in shoot (8030 mg/kg) and root (16380 mg/kg) while C. odorata with highest values of pH, P, Ca and Mg in rhizospheric soil accumulated the least (root; 331.6 and shoot: 209.0 mg/kg). Pb was more in organic and residual fractions of rhizospheric and non-rhizospheric soils respectively. Reduction in pH, EC coupled with nutrients and DOM availability increased Pb uptake by plant

Synthesis of Silver Nanoparticles from the Aqueous Extract of Leaves of Ocimum sanctum for Enhanced Antibacterial Activity

The field of nanotechnology is the most active area of research in modern materials science. Though there are many chemical as well as physical methods, green synthesis of nanomaterials is the most emerging method of synthesis. We report the synthesis of antibacterial silver nanoparticles (AgNPs) using leaf broth of medicinal herb, Ocimum sanctum (Tulsi). The synthesized AgNPs have been characterized by UV-Vis spectroscopy, transmission electron microscopy (TEM), and X-ray diffractometry. The mean particle of synthesized NPs was found to be 18 nm, as confirmed by TEM. The qualitative assessment of reducing potential of leaf extract has also been carried out which indicated presence of significant amount of reducing entities. FTIR analysis revealed that the AgNPs were stabilized by eugenols, terpenes, and other aromatic compounds present in the extract. Such AgNPs stabilized by Tulsi leaf extract were found to have enhanced antimicrobial activity against well-known pathogenic strains, namely Staphylococcus aureus and E. coli

Evaluation of Lead and chromium tolerance and accumulation level in Gomphrena celosoides: A novel metal accumulator from lead acid battery waste contaminated site in Nigeria

Biology, tolerance, and metal (Pb and Cr) accumulating ability of Gomphrena celosoides were studied under hydroponic conditions. The seedlings were raised in Hoagland’s solution containing different concentrations of Pb (0, 500, 1000, 1500, 2000, 3000, 4000, and 5000mg l�1) and Cr (0, 50, 100, 150, 200, 300, and 400mg l�1). Biomass and metal accumulation in different plant parts were determined at seven (7) and fourteen (14) days after stress. Antioxidant enzyme activities, protein, and proline contents were estimated in stressed and unstressed plants. Gomphrena celosoides was able to tolerate Pb and Cr concentrations up to 4000 and 100mg l�1, respectively in hydroponic solution. Metal accumulation was concentration and duration dependent with the highest Pb (21,127.90 and 117,985.29mg kg�1) and Cr (3130.85 and 2428.90mg kg�1) in shoot and root, respectively found in the plants exposed to 5000mg l�1 Pb and 400mg l�1 Cr for 14 days. Proline, antioxidant enzyme activities, and protein contents were the highest in plant exposed to higher Pb and Cr concentrations for 7 and 14 days. Gomphrena celosoides could be considered as Pb and Cr accumulator with proline and increase in antioxidant enzyme activities being the tolerance mechanisms