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Soil salinity is one of the major limiting factors for poor crop yield in the world. Increasing salinity in the soil is a challenge for agriculture. In the recent past, plant growth-promoting rhizobacteria (PGPR) are being used to enhance plant growth in various conditions. However, the saline-tolerant PGPR are of great use for plant growth under saline condition. In the present study, saline-tolerant E. hormaechei (MF957335) was isolated from saline water. E. hormaechei (MF957335) was tested for its potassium and calcium solubilizing efficiency using Scanning Electron Microscopy–Energy Dispersive X-Ray (SEM–EDX). E. hormaechei (MF957335) and K-Feldspar treatments significantly increased plant growth as compared to untreated plants (negative control). E. hormaechei (MF957335) significantly increased fresh biomass, shoot and root length of tomato plants. Among all the NaCl treatments, maximum fruits (9.66) were achieved in 250 mM NaCl + E. hormaechei treatment. Similar results with increased fruit numbers were obtained in K-Feldspar-treated plants. Apart from the plant growth, fresh biomass and fruit numbers, tomatoes from K-Feldspar-treated plants were large, fleshy and deep red colored. The study could demonstrate bioavailability of potassium from K-feldspar for tomato cultivation. Control plants tomato were small, non-fleshy, yellowish red, and infected with calcium deficiency disease blossom-end rot. The present study demonstrates the role of E. hormaechei (MF957335) in plant growth, yield promotion and disease tolerance by potassium and calcium solubilization, respectively. The study showed that E. hormaechei (MF957335) could be applied to saline and non-saline soils to enhance tomato yield.

Humans have been using natural resources for their daily life support. The population boom around the world has created a need to develop a new technique for increased crop production. Chemical fertilizers used in modern agriculture lead to pollution, besides increase in farming costs. To solve this problem, the present study deals with a natural halotolerant Enterobacter hormaechei which can fix N and solubilize desired macronutrients P and K. Enterobacter hormaechei was able to solubilize K-feldspar into potassium (97.5 ± 1.76 mg/L), tri-calcium phosphate into phosphate (99.7 ± 02 µg/mL) and it also produced IAA (47.87 ± 0.85 mg/L). Experiments, including morphological and chemical analysis, have provided a new growth pattern in Lycopersicum esculentum. Tomato seeds (Lycopersicum esculentum) treated with Enterobacter hormaechei enhanced biomass and an increase in shoot length when compared to control. It enhanced not only plant growth but modified the root architecture leading to improved crop productivity.

In recent years, the application of agricultural waste materials as an inexpensive source of substrate for the production of a high-value product is catching the eye of researchers. It is a fact that commercial cellulase is a high-cost product and also it is one of the significant industrial catalysts which in this study was produced from different agricultural wastes under solid-state fermentation. Bacillus licheniformis KY962963 an epiphytic bacterial strain of marine algae Chlorococcum sp. was used for cellulase production. The purpose of this study was to evaluate the effect of nutritious and ecological factors on the cellulase production from marine Bacillus licheniformis KY962963 . The efficacious parameters were primarily screened using the “Plackett- Burman” design. Subsequently, the key parameters such as P source, moisture content, time of incubation and incubation temperature were optimized by the “one factor at a time” approach. Lastly, the consequential parameters such as moisture content 75%, K2HPO4 2 g/L, incubation temperature 35 °C, and an incubation time of 3 days were found as the final optimum condition for higher production of cellulase.

The co-occurrence of arsenic, fluoride, and pathogens in water is a serious environmental issue. Thus, simultaneous mitigation of both ions, along with microbial contamination is a need base research effort in today’s scenario. ZrMAgo adsorbent having three-dimensional and porous architecture consists of intact zirconium and silver in its structural moiety is explored for this purpose. The adsorption isotherm models, i.e., Freundlich, Langmuir, and thermodynamic kinetics, have been studied to evaluate the kinetic behavior of ZrMAgo. The highest adsorption capacities (qmax) were obtained as 64 mg g−1 and 1.75 mg g−1 for F- and As(v) respectively (pH: 7.0 ± 0.2, initial F−: 50 mg L−1, As(v):1.0 mg L−1 and dose: 0.5 g L−1). Binding energies (−304 kJ mol−1 and −279 kJ mol−1) calculated by density functional theory, for F- and As(v) respectively supports good physical interactions at atomic and molecular levels. The disinfection behavior of ZrMAgo was examined against both Gram-positive and Gram-negative bacteria (Enterobacter hormaechei, Bacillus megaterium, and Bacillus bataviensis) in the presence of arsenic and fluoride in water. The process delivers safe water without leaching of ions while maintaining the pH (6.0 ± 0.2–8.0 ± 0.2).

Juncus rigidus is important halophyte with high cellulose content, but no studies has been made on micropropagation of the plant and cellulose extraction from in vitro shoots. To optimize an effective system for shoot multiplication, explants were grown in agar medium, liquid static culture, and bioreactor. Best shoot bud induction was obtained in liquid MS medium supplemented with2.27 μM thidiazuron (TDZ) over 0.46–4.65 μM Kinetin (KN) and 2.22–6.66 μM 6-benzyl aminopurine (BAP). Maximum number of shoot bud (36 ± 1.3) were achieved in static liquid MS medium supplemented with 2.22 μM BAP and 0.57 μM indole acetic acid (IAA). Upon subsequent subcultures >80 shoot buds were achieved in static liquid MS medium supplemented with 1.11 μM BAP, 0.57 μM IAA, and 0.46 μMKN within 30 days of culture. Being halophytic plant NaCl did not have any significant effect on shoot proliferation. Elongated shoots cultured in MS medium supplemented with 0.44 μM BAP, and 0.57 μM IAA developed 97% rooting in filter paper boat culture vessel. Sapling production cost in liquid culture medium was 90% less as compared to solid medium. Cellulose was extracted from the in vitro shoots and 17.64% cellulose achieved from liquid medium cultured shoots. For the first time micro-shoots are tested for in vitro cellulose production.

Cellulose is the salient constituent of plant biomass and a prolific renewable energy feedstock. The waste from industrial and agricultural matrices consists of sustainable amounts of cellulose that can effectively be utilized for the production of highly valued by-products. Extremophile bacterial cellulase is currently garnering the focus of researchers due its stability across broad temperature (40°C–130°C) and pH (6–10) ranges, making application for its use in food processing, paper/pulp industry, as an additive in the animal feed industry, textile industry, biofuel, and bioremediation. Cellulase activity is controlled via various metal ions that either induce or reduce the enzyme activity. In an attempt to achieve an efficient bioethanol production process, cellulase enzyme is under consideration as a potential biocatalyst. This chapter provides an overview of cellulase enzyme, specifically covering its bioconversion and utilization in biochemistry, genetics, and proteomics sectors.