Chemometric study on the biochemical marker of the manglicolous fungi to illustrate its potentiality as a bio indicator for heavy metal pollution in Indian Sundarbans

Traditional and new proposals for environmental microbial indicators-a review

The continuous increment in world population coupled with the greatest natural resource consumption and waste generation has an enormous impact on the environment. To date, using biological indicators (bioindicators) to evaluate the biological quality of natural environments is very common. Nonetheless, selecting those suitable for each ecosystem or contaminant is one of the most important issues for environmental sciences. Bacteria and helminths are mainly related to fecal contamination, while antibiotic-resistant bacteria, fungi, viruses, and microalgae are organisms used to determine deteriorated ecosystems by diverse contaminants. Nowadays, each bioindicator is used as a specific agent of different contaminant types, but detecting and quantifying these bioindicator microorganisms can be performed from simple microscopy and culture methods up to a complex procedure based on omic sciences. Developing new techniques based on the metabolism and physiological responses of traditional bioindicators is shown in a fast environmental sensitivity analysis. Therefore, the present review focuses on analyzing different bioindicators to facilitate developing suitable monitoring environmental systems according to different pollutant agents. The traditional and new methods proposed to detect and quantify different bioindicators are also discussed. Their vital role is considered in implementing efficient ecosystem bioprospection, restoration, and conservation strategies directed to natural resource management.

Enzymatic degradation and metabolic pathway of phenanthrene by manglicolous filamentous fungus Trichoderma sp. CNSC-2

Manglicolous filamentous fungi release extracellular lignolytic enzymes that can readily degrade polycyclic aromatic hydrocarbons (PAHs). The present study emphasizes the role of the extracellular enzyme in phenanthrene degradation by the manglicolous fungus Trichoderma sp. CNSC-2 isolated from the Indian Sundarban mangrove ecosystem. The removal efficiency reached 64.05 ± 0.75 % in 50 mg l-1 phenanthrene-amended mineral salt medium at pH 5.6 after 10 days of incubation. Phenanthrene removal was optimized at different pH, nutrient sources, and Cu2+ concentrations. The degradation significantly increased to 67.75 ± 4.32 % at pH 6 (P < 0.0001). The addition of Cu2+ (30 mg l-1) increased the degradation to 78.15 ± 0.36 % (P < 0.0001). The validation experiment confirmed the increase in phenanthrene degradation up to 79.9 ± 1.67 % under optimized conditions. The Lac1 and CytP450 genes encoding for extracellular and intracellular enzymes, respectively, were identified. The GC-MS derived phenanthrene degradation metabolites, i.e., phthalic acid, isobutyl 2-pentyl ester derivative, 1, 2 benzene dicarboxylic acid, butyl 2-methyl propyl ester derivative, TMS derivative of benzoic acid and 3,5 dihydroxy benzoic acid determined two possible metabolic pathways. The laccase enzyme activity was higher in the presence of Phe+Cu2+ (P < 0.0001), indicating the enzyme induction potential of PAH and Cu2+ ions. Purified laccase had a molecular weight of 45 kDa and was highly stable at pH 4-6 and temperature 20-50 °C. The enzyme retained 47 %, 87 %, and 63 % of enzyme activity at 30 mg l-1 concentration of Pb2+, Cd2+, and Hg2+. However, laccase activity was induced by 1.37 folds in the presence of 30 mg l-1 Cu2+ concentration. Thus, the study suggests the potential role of Trichoderma sp. CNSC-2 in phenanthrene degradation.

Exploring Microbial-Based Green Nanobiotechnology for Wastewater Remediation: A Sustainable Strategy

Water scarcity due to contamination of water resources with different inorganic and organic contaminants is one of the foremost global concerns. It is due to rapid industrialization, fast urbanization, and the low efficiency of traditional wastewater treatment strategies. Conventional water treatment strategies, including chemical precipitation, membrane filtration, coagulation, ion exchange, solvent extraction, adsorption, and photolysis, are based on adopting various nanomaterials (NMs) with a high surface area, including carbon NMs, polymers, metals-based, and metal oxides. However, significant bottlenecks are toxicity, cost, secondary contamination, size and space constraints, energy efficiency, prolonged time consumption, output efficiency, and scalability. On the contrary, green NMs fabricated using microorganisms emerge as cost-effective, eco-friendly, sustainable, safe, and efficient substitutes for these traditional strategies. This review summarizes the state-of-the-art microbial-assisted green NMs and strategies including microbial cells, magnetotactic bacteria (MTB), bio-augmentation and integrated bioreactors for removing an extensive range of water contaminants addressing the challenges associated with traditional strategies. Furthermore, a comparative analysis of the efficacies of microbe-assisted green NM-based water remediation strategy with the traditional practices in light of crucial factors like reusability, regeneration, removal efficiency, and adsorption capacity has been presented. The associated challenges, their alternate solutions, and the cutting-edge prospects of microbial-assisted green nanobiotechnology with the integration of advanced tools including internet-of-nano-things, cloud computing, and artificial intelligence have been discussed. This review opens a new window to assist future research dedicated to sustainable and green nanobiotechnology-based strategies for environmental remediation applications.

Fungal bioassays for environmental monitoring

Environmental pollutants are today a major concern and an intensely discussed topic on the global agenda for sustainable development. They include a wide range of organic compounds, such as pharmaceutical waste, pesticides, plastics, and volatile organic compounds that can be found in air, soil, water bodies, sewage, and industrial wastewater. In addition to impacting fauna, flora, and fungi, skin absorption, inhalation, and ingestion of some pollutants can also negatively affect human health. Fungi play a crucial role in the decomposition and cycle of natural and synthetic substances. They exhibit a variety of growth, metabolic, morphological, and reproductive strategies and can be found in association with animals, plants, algae, and cyanobacteria. There are fungal strains that occur naturally in soil, sediment, and water that have inherent abilities to survive with contaminants, making the organism important for bioassay applications. In this context, we reviewed the applications of fungal-based bioassays as a versatile tool for environmental monitoring.

Physiological mechanism of the response to Cr(VI) in the aerobic denitrifying ectomycorrhizal fungus Pisolithus sp.1

Pisolithus sp. 1 (P sp. 1) is an ectomycorrhizal fungus (EMF) with a strong Cr(VI) tolerance and reduction ability. The noninvasive microttest technique (NMT), real-time quantitative PCR (qRT-PCR), and the three-dimensional excitation-emission matrix (3D-EEM) were used to deeply explore the physiological mechanism of the P sp. 1 response to Cr(VI) and investigate the relationship between Cr(VI) reduction and denitrification in P sp. Cr(VI) induced the strongest elevations in nitrate reductase (NR) activity and NO production in the mycelia after treatment with Cr(VI) for 48 h under aerobic conditions. The NR inhibitor tungstate significantly inhibited Cr(VI) reduction, proton efflux and the expression of the NR gene (niaD) and NiR gene (niiA). In addition, NO was generated via NR-regulated denitrification. Combined treatments with Cr(VI) and the NO scavenger carboxy-PTIO (cPTIO) significantly increased O₂^-, H₂O₂ and MDA contents and reduced SDH, CAT, GSH, GR and GSNOR activity. Therefore, the NR-driven aerobic denitrifying process requires protons, and the generated NO reduces the oxidative stress effect of Cr(VI) on mycelia by reducing ROS accumulation and lipid peroxidation, enhancing mycelial and CAT activity, and promoting GSH recycling and regeneration. Psp.1 can also secrete humic acid-like and protein-like substances to combine with Cr(III) in a culture system.

Chemometric approach in environmental pollution analysis: A critical review

With the ever-increasing global population and industrialization, it has become a call of the hour to start taking care of the environment to balance the ecosystem. For this, effective monitoring and assessment are required, which involves collecting and measuring environmental details, temporal and spatial readings of environmental data, and parameters. However, assessment of the environment is very tedious as it includes monitoring target analytes, identifying their sources, and reporting, which invariably implies that detailed environmental monitoring would be an intricate and expensive process. The traditional protocols in environmental measures are often manual and time demanding, which makes it further difficult. Moreover, several changes also occur within the environment, which could be chemical, physical, or biological, and since these environmental impacts are often cumulative, it becomes difficult to measure an isolated system. Furthermore, the chances of skipping significant results and trends become high. Also, experimental data obtained from the environmental analysis are usually non-linear and multi-variant due to different associations among various contributing variables. Therefore, it is implied that accurate measurements and environment monitoring are not using traditional analytical protocols. Thus, the need for a chemometric approach in environmental pollution analysis becomes paramount due to the inherent limitations associated with the conventional approach of analyzing environmental datasets. Chemometrics has appeared as a potential technique, which enhances the particulars of the chemical datasets by using statistical and mathematical analysis methods to analyze chemical data beyond univariate analysis. Utilizing chemometrics to study the environmental data is a revolutionary idea as it helps identify the relationship between sources of contaminations, environmental drivers, and their impact on the environment. Hence, this review critically explores the concept of chemometrics and its application in environmental pollution analysis by briefly highlighting the idea of chemometrics, its types, applications, advantages, and limitations in the environmental domain. An attempt is also made to present future trends in applications of chemometrics in environmental pollution analysis.