The most significant and renewable class of polymeric materials are extracellular exopolysaccharides (EPSs) produced by microorganisms. Because of their diverse chemical and structural makeup, EPSs play a variety of functions in a variety of industries, including the agricultural industry, dairy industry, biofilms, cosmetics, and others, demonstrating their biotechnological significance. EPSs are typically utilized in high-value applications, and current research has focused heavily on them because of their biocompatibility, biodegradability, and compatibility with both people and the environment. Due to their high production costs, only a few microbial EPSs have been commercially successful. The emergence of financial barriers and the growing significance of microbial EPSs in industrial and medical biotechnology has increased interest in exopolysaccharides. Since exopolysaccharides can be altered in a variety of ways, their use is expected to increase across a wide range of industries in the coming years. This review introduces some significant EPSs and their composites while concentrating on their biomedical uses.

Marine algal polysaccharides (MAPs) are multifunctional biopolymers with significant potential in biomedical applications. Derived from brown, red, and green algae, key examples include alginate, agar, carrageenan, fucoidan, ulvan, and laminarin. Their structural diversity underlies a broad range of biological activities, particularly among sulfated polysaccharides, which exhibit antiviral, anticancer, anticoagulant, immunomodulatory, and antioxidant effects. Owing to their biocompatibility and tunable physicochemical properties, MAPs are also valuable in wound healing, tissue regeneration, and drug delivery. Advances in ultrasound-, microwave-, and enzyme-assisted extraction methods have enhanced yield and functionality. This review combines structural, extraction, and biomedical views on MAPs, with a focus on how molecular characteristics relate to their potential as drugs. Future work should focus on scalable green extraction, molecular-level characterization, and clinical validation to develop MAPs-based biomaterials for next-generation drug delivery, wound healing, and tissue engineering.

The urgent need to address environmental issues associated with the use of conventional fossil fuels has driven the rapid evolution of the global energy landscape. This review explores the background and significance of 3-G biofuel production, emphasizing the shift towards sustainable alternatives amidst escalating greenhouse gas emissions. While various renewable energy sources have gained prominence, biofuels have emerged as a promising solution for the transportation and industrial sectors, particularly from microalgal biomass. The rationale for focusing on microalgal biomass is based on its technical and environmental advantages. Unlike traditional feedstocks, microalgae boast a high lipid content, enhancing biofuel production efficiency. Their rapid growth rates and efficient carbon dioxide sequestration make microalgae frontrunners in scalable and sustainable biofuel production. This review aims to comprehensively analyze recent breakthroughs in 3-G biofuel production from microalgal biomass, filling gaps in the existing literature. The topics covered included species diversity, cultivation techniques, harvesting, pretreatment, lipid extraction methods, and biofuel production pathways. Genetic engineering, downstream processing, energy-efficient practices, and emerging trends, such as artificial intelligence and cross-disciplinary collaboration, will be explored. This study aims to consolidate recent research findings, identify challenges and opportunities, and guide future directions in microalgal biomass-based biofuel production. By synthesizing unpublished research, this review seeks to advance our knowledge and provide insights for researchers to foster sustainable and efficient 3-G biofuel production.

Biofertilizers derived from microorganisms are an environmentally friendly and economical alternative to chemical fertilizers, supporting sustainable agriculture by enhancing crop productivity. Halo-tolerant plant growth-promoting rhizobacteria (PGPR) can significantly improve the growth of plants in saline soils, which are becoming increasingly prevalent due to climate change. This study isolated and characterized nine rhizobacterial strains from the saline soil of Auraiya district, Uttar Pradesh, India. Among them, two of the isolates identified as (HS7) and (HS3), were selected based on their high salinity tolerance and plant growth-promoting properties. These isolates were formulated with talc and charcoal as carrier materials and tested for their efficacy in improving the growth of wheat plants in saline stress. The results demonstrated that both carriers were equally effective, suggesting that talc could be a more environmentally friendly alternative to charcoal. The study concludes that these PGPR strains can mitigate the negative effects of salinity on wheat crops, highlighting their potential as biofertilizers for sustainable agriculture.

Bioremediation of metallic pollutants using heavy metal-tolerant bacteria is crucial to environmental biotechnology. This biological process involves the removal of heavy metals from contaminated areas. The first step in bioremediation is the screening of metal-tolerant bacteria.In this study, the soil contamination level of a cement plant was investigated by measuring the concentration of certain heavy metals. This study aimed to screen lead-tolerant bacterial strains from contaminated cement soil for use in bioremediation. Sixteen lead-tolerant strains were isolated from the soil of the two cement plant areas. The strains exhibited varying levels of tolerance to lead, with minimal inhibitory concentrations (MIC) ranging from 15 to 33 mg L-1. The most tolerant strains were selected for further research to assess their potential for bioremediation.The metal tolerance levels of a bacterial community isolated from a cement dust-polluted soil environment were assessed using different methods, including agar dilution, gradient plate, and MIC. The results showed that the bacteria were able to tolerate high concentrations of lead and that the MIC method was the most effective in evaluating their tolerance.For further studies, most tolerant isolates were selected with maximum MIC values, including BCN-B1/5/Pb and BCN-B1/9/Pb from the BCN-B1 sample and PCN-P1/1/Pb from the PCN-P1 sample. These isolates demonstrated high tolerance to lead, with MIC values of 33, 33, and 31 mg L-1, respectively.

Centella asiatica, commonly known as Asiatic pennywort and Gotukola, harbors a wide variety of phytochemicals. This complex phytochemical composition of the plant makes it suitable for broad medicinal and commercial applications. The plant body provides a habitat for the growth and survival of various microorganisms and has its microbiome. In this study, efforts were made to isolate and identify bacterial inhabitants from the leaves of the plant. The bacterial isolates were further tested for osmotolerance activity which enables them to survive and grow in high salt concentrations. The high salt concentration is one of the important abiotic parameters which affects the growth of living organisms negatively. High salt concentration induces abiotic stress on the plant by producing an excessive amount of reactive oxygen species which leads to damage to biomolecules and osmotic shock. However, certain living organisms especially bacteria come under the group called osmotolerant and have molecular and biochemical machinery which help in the alleviation of this salt stress and enable them to survive in high salt concentrations. During the study, various bacteria were isolated from the phylloplane of C. asiatica using specific microbial cultural methods. The isolated bacterial populations were subjected to identification and characterization. Various morphological and biochemical methods were applied to characterize the bacterial isolates. The characterized bacteria were further grown on media plates containing an increasing amount of salts such as sodium chloride, mannitol, and sorbitol which help in the isolation of osmotolerant bacteria. The osmotolerant bacteria were finally identified using advanced molecular methods like 16s rRNA sequencing. The results of this study show that the plant has varieties of bacterial inhabitants in its phylloplane and all three bacterial isolates were known and identified for having osmotolerance activity.