Marine microbe with potential to adhere and degrade plastic structures

Extensive usages of plastics have led to their accumulation as a contaminant in natural environment worldwide. Plastic is an inert and non-biodegradable material, due to its complex structure and hydrophobic backbone [1]. Conventional methods for reduction of plastic waste such as burning, land-filling release unwanted toxic chemicals to the environment and harming living organism of land as well as the ocean. There is growing interest in development of strategies for the degradation of plastic wastes to clean the environment [2]. Marine bacteria have evolved with the capability to adapt and grow in the diverse environmental conditions [3]. We studied the ability of marine bacteria for destabilization and utilization of different plastic films (LDPE, HDPE, PVC and PET) as a sole source of carbon. An active bacterial strain AIIW2 was selected based on the triphenyl tetrazolium chloride reduction assay, and it was identified as Bacillus species based on 16S rRNA gene sequence. The viability of the strain over the plastic surface was studied and confirmed by bacLight assay with fluorescent probes. Scanning Electron Microscope and Atomic Force Microscope images suggested that bacterial interaction over the plastic surface is causing deterioration and roughness with increasing bacterial incubation time. In Fourier transform infrared spectra of treated plastic film evidenced stretching of the (-CH) alkane rock chain and (-CO) carbonyl region, suggested the oxidative activities of the bacteria. The results revealed that ability of bacterial strain for instigating their colonization over plastic films and deteriorating the polymeric structure in the absence of other carbon sources [4]. Moreover, production of extracellular enzymes such as esterase, laccase, and dehalogenase which are reported to support utilization of plastics was confirmed by plate assays. In concise, our results suggested that the marine bacterial strain AIIW2 have the ability to utilize different plastics and dictates the need for the further studies on the underlying biological process. We planned to explore the genes encoding the enzymes involved in degradation of plastic through whole genome study and metabolic profiling to investigate any phenotypic changes [5]. Establishing microbial resources for the degradation of plastics is an ecofriendly approach which could be useful in reduction of its accumulation

<span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:Calibri;mso-bidi-font-family:"Times New Roman"; color:#231F20;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: AR-SA" lang="EN-US">Utilization of seaweeds in enhancing productivity and quality of black gram [<i style="mso-bidi-font-style:normal"><span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:Calibri;mso-bidi-font-family:"Times New Roman"; color:#222222;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: AR-SA" lang="EN-US">Vigna </span></i><i style="mso-bidi-font-style:normal"><span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:Calibri;mso-bidi-font-family:"Times New Roman"; color:#231F20;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: AR-SA" lang="EN-US">mungo </span></i><span style="font-size:15.0pt;line-height: 115%;font-family:"Times New Roman";mso-fareast-font-family:Calibri;mso-bidi-font-family: "Times New Roman";color:#231F20;mso-ansi-language:EN-US;mso-fareast-language: EN-US;mso-bidi-language:AR-SA" lang="EN-US">(L.)<i style="mso-bidi-font-style:normal"> </i>Hepper] for sustainable agriculture</span></span>

16-22Seaweed and seaweed-derived products have been widely used as biostimulants for crop production, however, the biostimulatory potential of many seaweed’s extract has not been fully exploited due to the lack of scientific data on field experiments. In present investigation, a field experiment was carried to study the corollary of foliar application of seaweed extract on black gram [Vigna mungo (L.) Hepper] under rainfed condition during rainy (kharif) season of 2010. Seaweed extracts (prepared from Kappaphycus alvarezii and Gracilaria edulis) were applied to the foliage at diverse concentrations (0, 2.5, 5, 10 and 15%) twice during the crop period. It was found that both the extracts were very effective and enhanced the yield, growth and improved the quality of the produce. The yield of seed had increased by 47.52% and 42.52% with the application of K. alvarezii and G. edulis extracts, respectively when applied at 10% conc. Not only this, but other yield attributing characters, viz. number of pods/plant, pod weight, seed weight/plant and test weight of seed also have been augmented. The quality of seeds was also improved under the influence of the seaweed extract treatments. The foliar application of seaweed extracts to black gram crop has significantly increased uptake of almost all the nutrients. Thus, foliar applications of seaweed extracts could be a promising option for yield enhancement and sustainable agriculture

Utilization of seaweeds in enhancing productivity and quality of black gram [Vigna mungo (L.) Hepper] for sustainable agriculture

Seaweed and seaweed-derived products have been widely used as biostimulants for crop production, however, the biostimulatory potential of many seaweed’s extract has not been fully exploited due to the lack of scientific data on field experiments. In present investigation, a field experiment was carried to study the corollary of foliar application of seaweed extract on black gram [Vigna mungo (L.) Hepper] under rainfed condition during rainy (kharif) season of 2010. Seaweed extracts (prepared from Kappaphycus alvarezii and Gracilaria edulis) were applied to the foliage at diverse concentrations (0, 2.5, 5, 10 and 15%) twice during the crop period. It was found that both the extracts were very effective and enhanced the yield, growth and improved the quality of the produce. The yield of seed had increased by 47.52% and 42.52% with the application of K. alvarezii and G. edulis extracts, respectively when applied at 10% conc. Not only this, but other yield attributing characters, viz. number of pods/plant, pod weight, seed weight/plant and test weight of seed also have been augmented. The quality of seeds was also improved under the influence of the seaweed extract treatments. The foliar application of seaweed extracts to black gram crop has significantly increased uptake of almost all the nutrients. Thus, foliar applications of seaweed extracts could be a promising option for yield enhancement and sustainable agriculture

Microbial profiles of rhizosphere and bulk soil microbial communities of biofuel crops switchgrass (Panicum virgatum

The production of biofuels from the low-input energy crops, switchgrass (Panicum virgatum L.) and jatropha (Jatropha curcas L.), is a sustainable approach that can provide more usable energy and environmental benefits than food-based biofuels. Plant rhizosphere affects the microbial community structure due to variations in root exudation rates and residue chemistry. The objective of this investigation was to determine the profiles of microbial communities associated with rhizosphere and bulk soils of switchgrass or jatropha using phospholipid fatty acid (PLFA) analysis and length heterogeneity PCR (LH-PCR). Switchgrass soil contained a significantly (P &lt; 0.05) higher abundance of Gram-positive (i14:0, i15:0, a15:0), 16:1ω7c, 18:1ω5c), and saturated (14:0, 15:0) PLFAs compared to jatropha soil, whereas jatropha had a higher abundance of fungal (18:2ω6, 9c), 18:1ω9c, 20:1ω9c, and 18:0 PLFAs compared to switchgrass soil. Irrespective of plant type, rhizosphere soil contained a significantly (P &lt; 0.05) higher abundance of saturated PLFAs (16:0, 18:0, 20:0), actinomycetes (10Me17:0), and fungal (18:2ω6, 9c) PLFAs compared to bulk soil; whereas bulk soil had higher abundance of saturated (14:0), 16:1ω5c, 16:1ω7c), and 18:1ω9c PLFAs compared to rhizosphere soil. Multivariate principle component analysis of PLFAs and LH-PCR percent relative peak areas successfully differentiated the microbial communities of rhizosphere and bulk soils of switchgrass and jatropha

Spatial and halophyte-associated microbial communities in intertidal coastal region of India

<p>Microbial communities in intertidal coastal soils respond to a variety of environmental factors related to resources availability, habitat characteristics, and vegetation. These intertidal soils of India are dominated with <i>Salicornia brachiata, Aeluropus lagopoides</i>, and <i>Suaeda maritima</i> halophytes, which play a significant role in carbon sequestration, nutrient cycling, and improving microenvironment. However, the relative contribution of edaphic factors, halophytes, rhizosphere, and bulk sediments on microbial community composition is poorly understood in the intertidal sediments. Here, we sampled rhizosphere and bulk sediments of three dominant halophytes (<i>Salicornia, Aeluropus</i>, and <i>Suaeda</i>) from five geographical locations of intertidal region of Gujarat, India. Sediment microbial community structure was characterized using phospholipid fatty acid (PLFA) profiling. Microbial biomass was significantly influenced by the pH, electrical conductivity, organic carbon, nitrogen, and sodium and potassium concentrations. Multivariate analysis of PLFA profiles had significantly separated the sediment microbial community composition of regional sampling sites, halophytes, rhizosphere, and bulk sediments. Sediments from <i>Suaeda</i> plants were characterized by higher abundance of PLFA biomarkers of Gram-negative, total bacteria, and actinomycetes than other halophytes. Significantly highest abundance of Gram-positive and fungal PLFAs was observed in sediments of <i>Aeluropus</i> and <i>Salicornia</i>, respectively than in those of <i>Suaeda</i>. The rhizospheric sediment had significantly higher abundance of Gram-negative and fungal PLFAs biomarkers compared to bulk sediment. The results of the present study contribute to our understanding of the relative importance of different edaphic and spatial factors and halophyte vegetation on sediment microbial community of intertidal sediments of coastal ecosystem.</p

Seasonal variation in natural abundance of δ¹³C and ¹⁵N in <i>Salicornia brachiata</i> Roxb. populations from a coastal area of India

<p>High and fluctuating salinity is characteristic for coastal salt marshes, which strongly affect the physiology of halophytes consequently resulting in changes in stable isotope distribution. The natural abundance of stable isotopes (δ¹³C and δ¹⁵N) of the halophyte plant <i>Salicornia brachiata</i> and physico-chemical characteristics of soils were analysed in order to investigate the relationship of stable isotope distribution in different populations in a growing period in the coastal area of Gujarat, India. Aboveground and belowground biomass of <i>S. brachiata</i> was collected from six different populations at five times (September 2014, November 2014, January 2015, March 2015 and May 2015). The δ¹³C values in aboveground (−30.8 to −23.6 ‰, average: −26.6 ± 0.4 ‰) and belowground biomass (−30.0 to −23.1 ‰, average: −26.3 ± 0.4 ‰) were similar. The δ¹³C values were positively correlated with soil salinity and Na concentration, and negatively correlated with soil mineral nitrogen. The δ¹⁵N values of aboveground (6.7–16.1 ‰, average: 9.6 ± 0.4 ‰) were comparatively higher than belowground biomass (5.4–13.2 ‰, average: 7.8 ± 0.3 ‰). The δ¹⁵N values were negatively correlated with soil available P. We conclude that the variation in δ¹³C values of <i>S. brachiata</i> was possibly caused by soil salinity (associated Na content) and N limitation which demonstrates the potential of δ¹³C as an indicator of stress in plants.</p

Synthesis, Antifungal Ergosterol Inhibition, Antibiofilm Activities, and Molecular Docking on β‑Tubulin and Sterol 14-Alpha Demethylase along with DFT-Based Quantum Mechanical Calculation of Pyrazole Containing Fused Pyridine–Pyrimidine Derivatives

Multidrug-resistant fungal infections have become much more common in recent years, especially in immune-compromised patients. Therefore, researchers and pharmaceutical professionals have focused on the development of novel antifungal agents that can tackle the problem of resistance. In continuation to this, a novel series of pyrazole-bearing pyrido­[2,3-d]­pyrimidine-2,4­(1H,3H)-dione derivatives (4a–4o) have been developed. These compounds have been screened against Candida albicans, Aspergillus niger, and Aspergillus clavatus. The synthesized compounds were characterized by well-known spectroscopic techniques, i.e., IR, 1H NMR, 13C NMR, and mass spectrometry. In vitro antifungal results revealed that compound 4n showed activity against C. albicans having MIC value of 200 μg/mL. To know the plausible mode of action, the active derivatives were screened for anti-biofilm and ergosterol biosynthesis inhibition activities. The compounds 4h, 4j, 4k, and 4n showed greater ergosterol biosynthesis inhibition than the control DMSO. To comprehend how molecules interact with the receptor, studies of molecular docking of 4k and 4n have been performed on the homology-modeled protein of β-tubulin. The molecular docking revealed that the active compounds 4h, 4j, 4k, 4l, and 4n interacting with the active site amino acid of sterol 14-alpha demethylase (PDB ID: 5v5z) indicate one of the possible modes of action of ergosterol inhibition activity. The synthesized compounds 4c, 4e, 4h, 4i, 4j, 4k, 4l, and 4n inhibited biofilm formation and possessed the potential for anti-biofilm activity. DFT-based quantum mechanical calculations were carried out to optimize, predict, and compare the vibration modes of the molecule 4a