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Microbial degradation of textile dye reactive blue 250 (RB 250) by the novel Pseudomonas aeruginosa RGB11: a sustainable approach
Untreated textile effluent discharge has increased due to rapid industrialization and human activity, posing a serious and growing threat to environmental well-being over the past few decades. This study isolates a novel bacterial strain, Pseudomonas aeruginosa RGB11, from sewage sludge capable of degrading the azo dye Reactive Blue 250 dye (RB 250) as identified via 16S rRNA gene sequencing. Decolorization of RB 250 was tested in Minimal Salt Media (MSM) throughout the studies. Under static conditions, pH 7, and 37C, the dye showed 88.91% decolorization after 24h, which increased to 96.27% at pH 9 and 93.15%at 45C. Adding 1% w/v sucrose and yeast extract as carbon and nitrogen sources increased the decolorization to 96.83% and 97.54%, respectively. A study on growth kinetics over 8h showed that as the Optical Density (OD) of bacteria increased at 600nm, the absorbance of the dye decreased at 604nm, indicating the bacterial role in the decolorization process. FT-IR analysis of the metabolite extracted after decolorization revealed the shift in the intensity of the characteristic peak of the RB 250 dye and the formation of new peaks, which can be attributed to the degradation of dye and generation of intermediates in the decolorized solution. The LCMS study further confirms degradation as the parental peak in the dye disappeared and smaller new peaks were observed, possibly due to breakage of characteristic bonds in dye like the azo bond. Haemolysis test on blood agar demonstrated gamma haemolysis confirming that the novel strain of Pseudomonas aeruginosa RGB11 doesnt produce haemolysins and is a non-pathogenic strain. Thus, emphasizing the efficiency of Pseudomonas aeruginosa RGB11 as potential candidate for dye decolourizer for textile effluents. It has immense potential to serve as a contributor to environmental studies by providing a means of sustainable bioremediation for textile effluents. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia 2025. -
Microbial engineering strategies for synthetic microplastics clean up: A review on recent approaches
Microplastics are the small fragments of the plastic molecules which find their applications in various routine products such as beauty products. Later, it was realized that it has several toxic effects on marine and terrestrial organisms. This review is an approach in understanding the microplastics, their origin, dispersal in the aquatic system, their biodegradation and factors affecting biodegradation. In addition, the paper discusses the major engineering approaches applied in microbial biotechnology. Specifically, it reviews microbial genetic engineering, such as PET-ase engineering, MHET-ase engineering, and immobilization approaches. Moreover, the major challenges associated with the plastic removal are presented by evaluating the recent reports available. 2022 Elsevier B.V. -
Microbial Enzymes for Synthesis of Chiral Drug Intermediates
Microbes or microbial enzymes can catalyze the synthesis of bioorganic compounds, and this process is defined as biocatalysis. Biocatalysis has become an essential technique in organic biotransformation, typically applied in chemical industries. Biocatalysts generally show high activity and excellent enantio, stereo, regio, and chemo-selectivity. They offer practical and cost-effective ways to synthesize semi-synthetic analogues and novel drug molecules. Many bacteria and fungi-derived enzymes could catalyze highly specific hydroxylations of various substrates that are highly complex to synthesize by chemical methods. This chapter details and discusses different biocatalytic microbial platforms that permit to produce the chiral drug intermediates. 2023 selection and editorial matter, Ranjna Sirohi, Amit Kumar Rai, Luciana Porto de Souza Vandenberghe, and Binod Parameswaran; individual chapters, the contributors -
Microbial fuel cells for electricity generation and environmental bioremediation
The environmental impact on the use of fossil fuels and their unsustainable nature has led to the development of techniques using renewable energy and fuel cells. The recent decade has captured the attention of scientists towards the importance of microbial fuel cells (MFCs) with the role of microbial ability in converting organic wastes directly to electricity through microbially catalyzed anodic reactions along with microbial/enzymatic cathodic electrochemical reactions. MFC represents an environmental friendly approach for the use of generating electricity using wastewater, thus ensuring a bioremedial approach for effluent treatment with the achievement of chemical oxygen demand (COD) of about 50% chemical oxygen demand and power densities. This MFC utilises microbial metabolism for electricity generation. The overall performance of electricigens or MFC is based on the reactor design, operating conditions, electrode material used, types of substrates, and microorganisms involved. The optimization parameters studies for commercial production and their applications for MFC need to be intensified. Microbes have applications as biopolymer electrolytes that can be variously used in the applications of batteries, fuel cells and dye-sensitized solar cells. The use of MFCs has many advantages as they are eco-friendly, they have high performance abilities and they are costeffective and therefore can be used for modern applications. 2022 by Nova Science Publishers, Inc. -
Microbial Fuel Cells: The Microbial Route for Bioelectricity
The quest for sustainable energy sources serves as the essential pillar for development of humans since the dawn of civilization. The alarming increase in demand of energy, especially electricity propelled the need to screen for alternative sources of energy over the conventional fossil based non-renewable counterparts. Electricity generation through microbial route functions by the fundamental phenomena of electron transport chain and the microbes operate as the source of energy production utilizing the substrate. Since its initiation, microbial fuel cell has gained a lot of research focus from all over the world. The integration of waste treatment with power generation was highlighted as the most productive and sustainable part of microbial fuel cells. Over the past few decades, a lot of research and development was done on improving the design of fuel cells, searching for cost-effective electrodes and membranes for commercialization. Despite tremendous research done on this domain, its commercialization still faces a lot of hurdles especially once it comes to the overall maintenance and production cost. This chapter summarizes the basic architecture of different microbial fuel cells and the challenges that need to be addressed for making microbial fuel cells a sustainable route for the bioelectricity generation from microorganisms. Springer Nature Singapore Pte Ltd. 2020. -
Microbial Pigments in Textile and Dyeing Industries
[No abstract available] -
Microbial Polyhydroxyalkanoates (PHAs): A Review on Biosynthesis, Properties, Fermentation Strategies and Its Prospective Applications for Sustainable Future
Exponential increase in the use and disposal of synthetic plastics has raised an alarming concern related to their adverse effect on the environment due to their recalcitrant nature and non biodegradability. Nevertheless, the depletion in the petrochemical sources made it imperative to search for other sustainable alternatives to synthetic plastics. This triggered the attention on biodegradable plastics produced from plants, animals and microbial sources that have excellent material properties like their synthetic counterparts. Polyhydroxyalkanoates (PHAs) are ineluctably promising microbial polyesters that have the competence to supersede traditional oil-based synthetic polymers which causes major disposal issues worldwide. The compostable nature, biocompatibility, thermostability, and resilience of these bio-based polymers make them an acceptable replacement in the global market. Their versatile material properties made them a propitious candidate in packaging, biomedicine, tissue engineering, biofuel production, nanocomposite formation, and other industrial applications. Despite their potential advantages, the commercialization of PHA is hindered majorly due to the high cost associated with their production and extraction. This review work majorly focuses on the production, extraction, applications and fermentation strategies for enhancing PHA production. The review also addresses the production of PHA from extremophiles, challenges associated with PHA production and sustainable substrates for PHA production using various agroindustrial wastes. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Microbial Synthesis of Alkaloids and Applications in Healthcare
Plant alkaloids are a large group of natural compounds with wide-ranging bioactive characteristics, but the number of alkaloids obtained from the plant is low. Mass extraction of these bioactive alkaloids is affected by the trouble in large-scale propagation of these plants and absence of efficient strategies for extraction. However, production by chemical reactions is a substitute method; it is less effective due to its highly complex structure. The extensive study of alkaloid biosynthesis in plants and the advancement of genetic and metabolic engineering techniques enabled the opportunity to synthesise alkaloids through microbial hosts via metabolic engineering and bioprocess optimisations. In this chapter, we discuss the various gene-manipulation strategies to produce alkaloids in various microbial hosts and their application in the healthcare industry. 2023 selection and editorial matter, Ranjna Sirohi, Amit Kumar Rai, Luciana Porto de Souza Vandenberghe, and Binod Parameswaran; individual chapters, the contributors -
Microcannular electrode/polymer electrolyte interface for high performance supercapacitor
In the present work, the ionic resistance in the activated carbon (AC) electrode and blend polymer electrolyte (BPE) interface is reduced by tuning binder and BPE. A unique microcannulars channel connecting AC, binder and gaur gum (GG)/polyvinylalcohol (PVA) electrolyte is developed for easy Li+ movement. The use of AC derived from areca nut and natural GG as a binder makes the developed method more environmentally sustainable. The presence of microcannular structures on the electrode surface and BPE was confirmed using SEM and TEM analysis. Combined DSC-TGA data for BPE showed that PVA provides the mechanical support to jelly guar gum. The ionic conductivity, activation energy, dielectric studies were studied to understand the electrode/electrolyte interface mechanism. Dielectric studies revealed that the unique pathway of microcannular structures reduces the charge transfer resistance significantly at the interface. Optimized BPE was used in the fabrication of supercapacitor and specific capacitance was found to be 542 Fg-1. The time constant was 0.4 s and showed consistent cyclic pattern during galvanostatic charge/discharge studies with 99% Columbic efficiency. 2020 Elsevier Ltd -
Microencapsulated spirulina fortified yoghurt - An insight into physicochemical and sensory properties
Yoghurt is a widely consumed dairy product having good nutritional and functional properties. Incorporation of spirulina can enhance its health benefits due to its rich protein and antioxidant activity. However, direct addition affects sensory attributes, leading to reduced consumer acceptance. This study evaluates the impact of microencapsulated Spirulina-fortified yoghurt (ME-SP yoghurt) (treatment) on its physicochemical, microbiological and sensory properties, comparing it with plain yogurt as the negative control and Spirulina-incorporated yoghurt (without encapsulation) as the positive control. Results indicated that spirulina incorporation increased protein content in both positive control and treatment, but negatively influenced sensory acceptance in treatment due to colour and flavour changes. Microencapsulation effectively masked undesirable sensory characteristics while preserving nutritional benefits and an increase in protein content by 4.05%. More quantity of spirulina (1%) could be added to yoghurt when we used encapsulated spirulina than spirulina without encapsulation (0.5%). Textural analysis showed improved viscosity and stability in the microencapsulated sample than PC and NC. Microbiological analysis confirmed the probiotic viability in all samples within the acceptable range, based on the Food Safety and Standards Authority of India (FSSAI) and Codex Alimentarius standards for fermented dairy products. Sensory evaluation revealed that microencapsulation significantly enhanced flavour (7.9) compared to direct spirulina addition (6.96). This study concludes that microencapsulation is a viable technique to enhance the functional properties of spirulina-enriched yoghurt while maintaining its sensory appeal. 2025 Indian Council of Agricultural Research. -
Microfinance Sector and the Supportive Role of Regulator in its Transformation: A Case Study from India
Microfinance is a proven business model to deliver financial services to unbanked. In the beginning years of microfinance, Non-Governmental Organizations (NGOs) were engaged in microfinance initiative and used to raise capital through grants for their microfinance program, similar to other grant-based development initiatives. To become self-sustainable financial institutions, NGOs started to transform their microfinance initiatives to a for-profit legal entity. Microfinance experienced commercialization in the process of transformation which neglected the basics of microfinance, especially in protecting the interest of clients. Supportive role of regulator transformed the Indian microfinance sectors and formed sustainable financial institutions. The successful story of Reserve Bank of Indias (RBI) intervention in shaping Indian microfinance sector counters the argument of free market principle in fixing the interest rate and healthy regulation for microfinance institutions. Supportive role of Reserve Bank of India created win-win situation for both microfinance borrowers, microfinance institutions and other stakeholders for the long-term sustainability. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021. -
Microgrid Energy Management- An Optimization Approach for Operational Cost Reduction
Optimization-based energy management and the related economic viability analysis of replacing a diesel generator alone-based microgrid with a PV, battery, fuel cell and diesel generator-based hybrid microgrid to minimize the operations cost, considering battery degradation and emissions, are presented in this work. The fuel cell considered here is the hydroplus fuel cell, which has minimum emissions, and eliminates the need for hydrogen storage. Mathematical modeling is based on experimentally obtained parameters for fuel consumption coefficients and emissions. The study considers an islanded mode of operation with two different scenarios of microgrid configuration, the first case with the hybrid microgrid working under optimal power conditions, and the second case with only diesel generator available to meet the load demand, for four representative months of the year. Comparing the operations cost under the two scenarios, replacement of a diesel generator-based microgrid, with a PV/battery/hydroplus fuel cell/diesel generator based microgrid resulted in reduction of daily operations cost by 54.06%, 35.25%, 34.38% and 32.71% for the months of January, April, July and October respectively. A sensitivity analysis with varied costs of fuel, operation and maintenance, and battery degradation proved that irrespective of these costs, a considerable amount of reduction in the operations cost is achieved. The results presented here are highly beneficial for application in microgrids worldwide. 2025 IEEE. -
Microhardness studies of GaTe whiskers
Single crystal whiskers of gallium telluride (GaTe) have been grown by the physical vapour deposition (PVD) method. Microindentation studies were carried out on the prism faces of the needles to understand their mechanical behaviour. The variation in the microhardnessof GaTe crystals with applied load has been determined at room temperature using Vickers microhardness indenter. The work- hardening exponent has also been computed for different load regions. 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. -
Microhardness studies of vapour grown tin (II) sulfide single crystals
Earth abundant tin sulfide (SnS) has attracted considerable attention as a possible absorber material for low-cost solar cells due to its favourable optoelectronic properties. Single crystals of SnS were grown by physical vapour deposition (PVD) technique. Microindentation studies were carried out on the cleaved surfaces of the crystals to understand their mechanical behaviour. Microhardness increased initially with the load, giving sharp maximum at 15 g. Quenching effect has increased the microhardness, while annealing reduced the microhardness of grown crystals. The hardness values of as-grown, annealed and quenched samples at 15 g load are computed to be 99.69, 44.52 and 106.29 kg/mm 2 respectively. The microhardness of PVD grown crystals are high compared to CdTe, a leading low-cost PV material. The as-grown faces are found to be fracture resistant. 2015 AIP Publishing LLC. -
Microindentation Analysis of Bi2Te3 Crystals
Recent trends and advancements in materials research and technology have led to a renewed interest in the growth of crystalline solids with better physical perfection and high purity. The major emphasis of investigations has been on the growth of single crystals and the study of their physical properties suitable for device fabrication. The availability of crystals from natural resources is inadequate to meet the need of industries and also do not give sufficient variety. Although crystal growth has been the subject of absorbing interest for many years, much of the latest developments have been stimulated due to its increasing commercial importance for the fabrication of thermoelectric, optoelectric and nonlinear optical devices. Crystal has an ordered arrangement of atoms or molecules in microscopic scale and the atomic regularity shows up in the internal and external symmetry. The change in crystal shape should be brought about by the difference in controlling mechanisms of the growth dynamics. It is inevitable to investigate the relationship between the growth mechanism and resulting growth morphology. The developments in crystal technology have significant contribution to many areas of basic and applied solid state research. Industries currently rely on bulk grown crystals of a variety of materials. Hence, single crystals have been extensively studied to explore their novel physical properties and potential applications. The first chapter deals with an introduction to the crystal growth, followed by a brief history of semiconducting materials. A detailed account on the properties and applications of bismuth telluride crystals is reported. This chapter concludes with different mechanical properties and scope of the research problem. A review of literature to present theoretical knowledge on growth and characterization of bismuth telluride crystals is given in chapter 2. Chapter 3 outlines the experimental procedures and different characterization techniques used for the present work. A detailed study on the vapour and melt growth of bismuth telluride crystals and its mechanical properties is also reported. Chapter 4 is devoted to provide a detailed discussion on the results obtained from experimental research. Final chapter covers the summary and conclusions of this research work. The report ends with a reference section, listed as per the international standards. -
Microlearning and Learning Performance in Higher Education: A Post-Test Control Group Study
This study aimed at evaluating the effectiveness of microlearning in higher education. The sample consisted of first-year MBA students, and a post-test control group design was used to assess the effectiveness of a microlearning module. The results indicated that the use of microlearning was significantly related to learning performance and participants' reactions to the module. Moreover, the microlearning group scored significantly higher than the control group. The findings suggest that microlearning has the potential to improve learning outcomes and enhance participant engagement. However, the study has certain limitations, and future research is needed to gain a comprehensive understanding of the optimal design and delivery of microlearning modules. The study supports the use of microlearning in higher education as an effective instructional strategy. 2024, Commonwealth of Learning. All rights reserved. -
Micromachining process-current situation and challenges
The rapid progress in the scientific innovations and the hunt for the renewable energy increases the urge for producing the bio electronic products, solar cells, bio batteries, nano robots, MEMS, blood less surgical tools which can be possible with the aid of the micromachining. This article helps us to understand the evolution and the challenges faced by the micromachining process. Micro machining is an enabling technology that facilitates component miniaturization and improved performance characteristics. Growing demand for less weight, high accuracy, high precision, meagre lead time, reduced batch size, less human interference are the key drivers for the micromachining than the conventional machining process. Owned by the authors, published by EDP Sciences, 2015. -
Microplastic pollution and its ecotoxicological impact: Evidence from Vembanad Lake and zebrafish studies
Microplastic (MP) contamination is a threat to Earth and its aquatic systems by destabilizing ecological equilibrium. This study examined the distribution and impact of MPs in Vembanad Lake, an urbanized estuarine system in Kerala, India. MPs were identified at every sampling location, while sites 2, 3, and 4 exhibited peak contamination levels of 79 MPs/L. A survey among local inhabitants reported a decline in fish populations over many years. Analytical characterization using SEM, EDS, FTIR, and Raman spectroscopy revealed the dominance of HDPE, LDPE, PS, PET, PP, and PVC polymers. The presence of chromium (Cr), sodium (Na), aluminum (Al), and silica (SiO?) in MPs further enhances additional toxicity risks. Zebrafish exposed to the prevalent MPs for 21 days exhibited severe epithelial necrosis alongside goblet cell hyperplasia and muscle fiber degeneration, demonstrating systemic cytotoxic effects. These findings underscore the ecological threat of MP pollution and emphasize the urgent need for mitigation strategies to protect aquatic biodiversity. 2025 Elsevier B.V. -
Microplastic residues in clinical samples: A retrospection on sources, entry routes, detection methods and human toxicity
Microplastics (MPs) are emerging toxicants which have been detected in varying environments. Despite MPs adverse effects, reports on MPs detection from human clinical samples are only a few. This is due to several reasons such as inefficiency of current MPs detection techniques to detect them from human clinical samples, lack of understanding about the MPs toxicity to human organs and ethical regulations that restricts study with human placental exposure to MPs. This review gives a comprehensive outlook on the major sources MPs sources and routes into human system and their human toxicity mechanisms. Further an in-depth discussion on the significance and limitations of various MPs detection methods is elaborated in the review. Challenges in current research framework for detection of MPs from human clinical samples and the possible future directions in this imperative research domain are also focused in this review. 2024 Elsevier B.V. -
Microplastics distribution and potential health implications of food and food products
Microplastics, miniscule plastic fragments ubiquitous in the environment, pose a growing threat as they infiltrate our food chain. This review delves into the contamination of various food categories, including seafood, agricultural products, and even processed foods through packaging and processing methods. Developing reliable analytical techniques to accurately detect microplastics levels within complex food matrices is crucial to gauge the true extent of this contamination. Although the entire range of potential health effects associated with microplastic intake is not yet known, there is reason to be concerned about the risks. These include the potential for microplastics to physically hurt the gastrointestinal tract, exposure to chemicals that seep from the polymers themselves, and the potential for microplastics to act as carriers for other dangerous compounds. This analysis identifies important knowledge gaps about the long-term health effects of microplastics exposure. It highlights the urgent need for more investigation to fully assess the possible dangers connected to microplastics in the food chain. Furthermore, it is imperative that efficient mitigation measures be put in place as soon as possible to protect food safety from microplastics contamination. More cooperation is required to create more stringent laws governing the use of plastic, investigate substitute materials for manufacturing and packaging, and create effective filtering systems for the processing of food and water. Through devoted research to close knowledge gaps and the implementation of strong mitigation strategies, can make proactive efforts to safeguard public health and maintain the integrity of our food supply chain for future generations. 2024 Elsevier Inc.