Bacterial cellulase from the intestinal tract of the sugarcane borer

Identification of Cellulose-Degrading Bacteria and Assessment of Their Potential Value for the Production of Bioethanol from Coconut Oil Cake Waste

Bioconversion of lignocellulosic biomass is a highly promising alternative to rapidly reduce reliance on fossil fuels and greenhouse gas emissions. However, the use of lignocellulosic biomass is limited by the challenges of efficient degradation strategies. Given this need, Bacillus tropicus (B. tropicus) with cellulose degradation ability was isolated and screened from rotten dahlia. The strain efficiently utilized coconut oil cake (COC) to secrete 167.3 U/mL of cellulase activity. Electron microscopy results showed significant changes in the structure and properties of cellulose after treatment with B. tropicus, which increased the surface accessibility and the efficiency of the hydrolysis process. The functional group modification observed by Fourier transform infrared spectroscopy indicated the successful depolymerization of COC. The X-ray diffraction pattern showed that the crystallinity index increased from 44.8% to 48.2% due to the hydrolysis of the amorphous region in COC. The results of colorimetry also reveal an efficient hydrolysis process. A co-culture of B. tropicus and Saccharomyces cerevisiae was used to produce ethanol from COC waste, and the maximum ethanol yield was 4.2 g/L. The results of this work show that B. tropicus can be used to prepare biotechnology value-added products such as biofuels from lignocellulosic biomass, suggesting promising utility in biotechnology applications.

The pivotal roles of gut microbiota in insect plant interactions for sustainable pest management

The gut microbiota serves as a critical "organ" in the life cycle of animals, particularly in the intricate interplay between herbivorous pests and plants. This review summarizes the pivotal functions of the gut microbiota in mediating the insect-plant interactions, encompassing their influence on host insects, modulation of plant physiology, and regulation of the third trophic level species within the ecological network. Given these significant functions, it is plausible to harness these interactions and their underlying mechanisms to develop novel eco-friendly pest control strategies. In this context, we also outline some emerging pest control methods based on the intestinal microbiota or bacteria-mediated interactions, such as symbiont-mediated RNAi and paratransgenesis, albeit these are still in their nascent stages and confront numerous challenges. Overall, both opportunities and challenges coexist in the exploration of the intestinal microbiota-mediated interactions between insect pests and plants, which will not only enrich the fundamental knowledge of plant-insect interactions but also facilitate the development of sustainable pest control strategies.

Microbial cellulase production and its potential application for textile industries

Purpose

The textile industry’s previous chemical use resulted in thousands of practical particulate emissions, such as machine component damage and drainage system blockage, both of which have practical implications. Enzyme-based textile processing is cost-effective, environmentally friendly, non-hazardous, and water-saving. The purpose of this review is to give evidence on the potential activity of microbial cellulase in the textile industry, which is mostly confined to the realm of research.

Methods

This review was progressive by considering peer-reviewed papers linked to microbial cellulase production, and its prospective application for textile industries was appraised and produced to develop this assessment. Articles were divided into two categories based on the results of trustworthy educational journals: methods used to produce the diversity of microorganisms through fermentation processes and such approaches used to produce the diversity of microbes through microbial fermentation. Submerged fermentation (SMF) and solid-state fermentation (SSF) techniques are currently being used to meet industrial demand for microbial cellulase production in the bio textile industry.

Results

Microbial cellulase is vital for increasing day to day due to its no side effect on the environment and human health becoming increasingly important. In conventional textile processing, the gray cloth was subjected to a series of chemical treatments that involved breaking the dye molecule’s amino group with Cl − , which started and accelerated dye(-resistant) bond cracking. A cellulase enzyme is primarily derived from a variety of microbial species found in various ecological settings as a biotextile/bio-based product technology for future needs in industrial applications.

Conclusion

Cellulase has been produced for its advantages in cellulose-based textiles, as well as for quality enhancement and fabric maintenance over traditional approaches. Cellulase’s role in the industry was microbial fermentation processes in textile processing which was chosen as an appropriate and environmentally sound solution for a long and healthy lifestyle.

First insights into the gut microbiome of Diatraea saccharalis: From a sugarcane pest to a reservoir of new bacteria with biotechnological potential

A country’s biodiversity is a key resource for the development of a sustainable bioeconomy. However, often the most biodiverse countries on the planet hardly profit from their biological diversity. On the contrary, occasionally components of that biodiversity become a threat to society and its food sustainability. That is the case of the sugarcane borer Diatraea saccharalis. Here, the analysis of the bacteria associated with the digestive tract of D. saccharalis reveals a rich and diverse microbiota. Two types of diets were analyzed under laboratory conditions. The metataxonomic analysis revealed a number of taxa common to most of the larval pools analyzed with relative abundances exceeding 5%, and five families of bacteria which have also been reported in the gut of another Lepidoptera. A large fraction of microorganisms detected by amplicon sequencing were considered to be rare and difficult to cultivate. However, among the cultivable microorganisms, 12 strains with relevant biotechnological features were identified. The strain that showed the highest cellulolytic activity (GCEP-101) was genome sequenced. The analysis of the GCEP-101 complete genome revealed that the values of 16S rRNA identity, the Average Nucleotide Identity, and the digital DNA–DNA hybridization place the strain as a candidate for a new species within the genus Pseudomonas. Moreover, the genome annotation of the putative new species evidenced the presence of genes associated with cellulose degradation, revealing the hidden potential of the pest as a reservoir of biotechnologically relevant microorganisms.

Characterization of Cellulose-Degrading Bacteria Isolated from Soil and the Optimization of Their Culture Conditions for Cellulase Production

The characterization of bacteria with hydrolytic potential significantly contributes to the industries. Six cellulose-degrading bacteria were isolated from mixture soil samples collected at Kingfisher Lake and the University of Manitoba campus by Congo red method using carboxymethyl cellulose agar medium and identified as Paenarthrobacter sp. MKAL1, Hymenobacter sp. MKAL2, Mycobacterium sp. MKAL3, Stenotrophomonas sp. MKAL4, Chryseobacterium sp. MKAL5, and Bacillus sp. MKAL6. Their cellulase production was optimized by controlling different environmental and nutritional factors such as pH, temperature, incubation period, substrate concentration, nitrogen, and carbon sources using the dinitrosalicylic acid and response surface methods. Except for Paenarthrobacter sp. MKAL1, all strains are motile. Only Bacillus sp. MKAL6 was non-salt-tolerant and showed gelatinase activity. Sucrose enhanced higher cellulase activity of 78.87 ± 4.71 to 190.30 ± 6.42 U/mL in these strains at their optimum pH (5-6) and temperature (35-40 °C). The molecular weights of these cellulases were about 25 kDa. These bacterial strains could be promising biocatalysts for converting cellulose into glucose for industrial purposes.

Analysis of Intestinal Microbial Diversity of Four Species of Grasshoppers and Determination of Cellulose Digestibility

Simple Summary

Grasshoppers are typical phytophagous pests, which prefer eating monocotyledons with more cellulose and hemicellulose. Due to its large appetite and high utilization rate, the intestinal contents of grasshoppers have the potential to be developed into a bioreactor, which can be applied to improve straw utilization efficiency in the future. The digestive tract of grasshoppers is a complex ecosystem, inhabited by a large number of microorganisms. The existence of these microorganisms enables grasshoppers to have high decomposition and utilization of plant fibers. However, there are few reports on the microflora structure and diversity of the digestive tract of grasshoppers. In this study, the diversity of symbiotic bacteria in the intestinal tract of four species of grasshoppers, namely Acrida cinerea, Trilophidia annulata, Atractomorpha sinensis and Sphingonotus mongolicus, was studied by using the method of constructing a 16S rRNA gene library and Illumina Miseq sequencing technology. At the same time, the digestibility of cellulose and hemicellulose of the four species of grasshoppers were determined and the relationship between digestibility and intestinal microbial diversity was analyzed. This study provided basic data for the development of the digestible bioreactor of cellulose and hemicellulose, which may provide a new idea for degrading straw.

Abstract

Grasshoppers (Insecta, Orthoptera, Acridoidea) are a large group of agricultural and animal husbandry pests. They have a large food intake with high utilization of plants fibers. However, the composition of the grasshopper gut microbial community, especially the relationship between gut microbial community and cellulose digestibility, remains unclear. In this research, 16S rRNA gene sequences were used to determine the intestinal microbial diversity of Acrida cinerea, Trilophidia annulata, Atractomorpha sinensis and Sphingonotus mongolicus, and Spearman correlation analysis was performed between the intestinal microbes of grasshoppers and the digestibility of cellulose and hemicellulose. The results showed that Proteobacteria was the dominant phylum and Klebsiella was the dominant genus in the guts of the four species of grasshoppers; there was no significant difference in the species composition of the gut microbes of the four species of grasshoppers. Spearman correlation analysis showed that Brevibacterium and Stenotrophomonas were significantly correlated with cellulose digestibility. Brevibacterium, Clavibacter, Microbacterium and Stenotrophomonas were significantly associated with hemicellulose digestibility. Our results confirmed that the gut microbes of grasshoppers were correlated with the digestibility of cellulose and hemicellulose, and indicated that grasshoppers may have the potential to develop into bioreactors, which can be applied to improve straw utilization efficiency in the future.

Harnessing the potential use of cellulolytic Klebsiella oxytoca (M21WG) and Klebsiella sp. (Z6WG) isolated from the guts of termites (Isoptera)

Background

For many years, denim-heavy quality cotton twill colored with indigo colors and with a well-worn/faded look has held a lot of appeal. Machine damage, drainage system blockage, and other issues come with the conventional usage of pumice stones for “stone-washing” denims. In view of the abovementioned information, a range of works has been done to investigate the economic prospects of bacterial cellulase enzymes for use in industrial processes, including biopolishing in the textile sector. Ethiopia has excellent termite diversity to isolate bacterial gut-associated cellulose enzymes for biostoning applications. The main purpose of this study was, therfore, to decipher how to isolate and characterize cellulase enzymes from termite (Isoptera) gut bacteria with the intention of employing it for biostoning of textiles.

Purpose

To use cellulolytic enzymes of Klebsiella oxytoca (M21WG) and Klebsiella sp. (Z6WG) isolated from termite guts in biostoning of textiles and improving garment quality.

Methods

Cellulase enzyme-producing bacteria were isolated and screened from the guts of worker termites sampled from Meki and Zeway termite mounds in the Central Rift Valley region of Ethiopia. Bacterial screening, biochemical, morphological, and 16S rRNA sequence identification techniques were employed to characterize the bacterial strains. In addition, the production, optimization, and purification of the associated cellulase enzymes were employed, and the potential application of the enzymes for biostoning of a textile was demonstrated.

Result

The isolated M21WG was found to be 99% identical to the Klebsiella oxytoca (MT104573.1) strain, while the isolated Z6WG showed 97.3% identity to the Klebsiella sp. strain (MN629242.1). At an ideal pH of 7, a temperature of 37 °C, a 72-h incubation time, and a substrate concentration of 1.5% carboxymethylcellulose sodium, the maximum activity of the crude cellulase extract from these bacteria was assessed. These bacteria produced cellulase enzymes that were moderately efficient. Consequently, it was determined that the cellulase enzymes were effective for biostoning of denim cloth.

Conclusion

It was determined that Klebsiella oxytoca (M21WG) and Klebsiella sp. (Z6WG) could be used as a doorway to better understand harnessing the use of these cellulase-producing bacteria from termite (Isoptera) guts. In this study, it was also attempted to assess the effectiveness of the two bacterial isolates in biostoning in anticipation of their potential application in the textile realm.