Heavy metal and pesticide pollution have become an inevitable part of the modern industrialized environment that find their way into all ecosystems. Because of their persistent nature, recalcitrance, high toxicity and biological enrichment, metal and pesticide pollution has threatened the stability of the environment as well as the health of living beings. Due to the environmental persistence of heavy metals and pesticides, they get accumulated in the environs and consequently lead to food chain contamination. Therefore, remediation of heavy metals and pesticide contaminations needs to be addressed as a high priority. Various physico-chemical approaches have been employed for this purpose, but they have significant drawbacks such as high expenses, high labor, alteration in soil properties, disruption of native soil microflora and generation of toxic by-products. Researchers worldwide are focusing on bioremediation strategies to overcome this multifaceted problem, i.e., the removal, immobilization and detoxification of pesticides and heavy metals, in the most efficient and cost-effective ways. For a period of millions of evolutionary years, microorganisms have become resistant to intoxicants and have developed the capability to remediate heavy metal ions and pesticides, and as a result, they have helped in the restoration of the natural state of degraded environs with long term environmental benefits. Keeping in view the environmental and health concerns imposed by heavy metals and pesticides in our society, we aimed to present a generalized picture of the bioremediation capacity of microorganisms. We explore the use of bacteria, fungi, algae and genetically engineered microbes for the remediation of both metals and pesticides. This review summarizes the major detoxification pathways and bioremediation technologies; in addition to that, a brief account is given of molecular approaches such as systemic biology, gene editing and omics that have enhanced the bioremediation process and widened its microbiological techniques toward the remediation of heavy metals and pesticides.

The intensive use of inorganic fertilizers and pesticides in the agricultural field has globally destroyed soil fertility, killed beneficial microorganisms, and also decreased natural resistance in crops, thereby making them more vulnerable to diseases besides affecting human health and the environment. To overcome these problems, it is very important to shift our attention towards eco-friendly alternatives like vermicompost and vermicompost tea which not only can increase crop growth and yield, suppress diseases and pests sustainably but can also protect human health and the environment. Vermicompost with its rich nutrient content, plant growth promoters like auxins, gibberellins, cytokinins, and beneficial microbes not only improves the growth and yield of crops but also increases the diversity and activity of antagonistic microbes and nematodes, which helps to suppress pests and diseases caused by soil-borne phytopathogens. Vermicompost tea also has a tremendous potential to protect plants from diseases and its application to plants can coat leaf surfaces and reduce available sites for pathogen infection or increases microbial diversity that can kill harmful pathogens. Here, we review recent scientific achievements towards the management of crop diseases and pests by these organic amendments and the major points are the following: (1) production of vermicompost and vermicompost tea, (2) management of crop pests and diseases by vermicompost and vermicompost tea, and(3) the possible mechanisms and some important factors involved in the suppression of diseases and pests. Finally, we conclude that by using these eco-friendly organic amendments as a replacement to inorganic pesticides and fungicides, diseases and pests can be managed successfully without affecting human health and the environment and chemical-free food can be provided to humankind in the future.

More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes.

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