Isolation of Polygalacturonase-Producing Bacterial Strain from Tomatoes (Lycopersicon esculentum Mill.)

Isolation and characterization of pectinase-producing bacteria (Serratia marcescens) from avocado peel waste for juice clarification

BACKGROUND

Bacterial pectinase is an enzyme that could be employed in numerous sectors to break down pectin polysaccharide compounds. The goal of this study is to find pectinase-producing bacteria in avocado peel waste and see if the pectinase enzyme produced can be used to make fruit juice clarification.

RESULTS

The researchers isolated four different bacterial strains from avocado peel waste samples. The potential two bacterial isolates that were identified as being Serratia marcescens and Lysinibacillus macrolides. Finally, the analysis of pectinase production and its application in fruit juice clarification were performed using one of the bacterial strains of Serratia marcescens. The clear apple, lemon, and mango juices were further processed to assess each juice's properties. The highest antioxidant activity was recorded in lemon juice samples. The lemon juice showed the highest total titratable acidity and total phenol content. Apple juices contained the highest total soluble solids, reducing sugar content, and viscosity and the mango juices have the maximum pH value recorded.

CONCLUSIONS

The pectinase isolated from the bacterium Serratia marcescens could clear fruit juices. This pectinase needs to be studied more to make sure it works better in the fruit industry and other businesses.

Pectinase from Microorganisms and Its Industrial Applications

The utilization of microbial pectinase in different industries has been increased in its world demand. The major sources of pectinase are microorganisms mainly bacteria, fungi and yeast. The utilization of low-cost agro-industrial wastes as substrates has been preferable in pectinase production. Pectinase production faced various parameters optimization constraints such as temperature, pH and production times which are the main factors in pectinase production. The pectinase enzyme is getting attention due to its several advantages; hence, it needs to be explored further to take its maximum advantage in different industries. This review discusses the pectin substance structure, substrate for pectinase production, factors influencing pectinase production, the industrial application of microbial pectinase and also discusses challenges and future opportunities of applying microbial pectinase in industry.

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.

Characterization and Phylodiversity of Implicated Enteric Bacteria Strains in Retailed Tomato (Lycopersicon esculentum Mill.) Fruits in Southwest Nigeria

BACKGROUND: Tomatoes (Lycopersicon esculentum Mill.) have very huge health-promoting benefits due to high nutritional composition; however, these fruits are potential reservoir of enteric food-borne pathogens causing major public health concerns. AIM: Characterization and phylo-analysis of implicated enteric bacteria strains in retailed Tomato fruits in southwest Nigeria were studied. METHODS: Ready to be retailed fresh tomato fruits were purchased from common food markets in southwest, Nigeria, which lies between latitudes 6° 21′ to 8° 30′ N and longitudes 2° 30′ to 5° 30′ E. Observation of sample storage potentials at different conditions and bio-typing of associated bacterial strains were carried out for consecutive 14 days. Enteric bacteria strains were genotyped with 16S rRNA assay and further profiled for antibiotic susceptibility to common antibiotics. High population rate frequently consume tomatoes. RESULTS: Early spoilage characterized with yellow fluid, fungal growth and visible lesions were observed at 25°C storage compare to few patches of lesion at 4°C after 14 days. Higher bacterial count of 4.0–7.18 Log CFU/g was recorded at ambient storage compare to refrigerated samples with more than 10% occurrence rate of Citrobacter spp., Klebsiella spp. and Enterobacter spp. Identified Citrobacter spp. and Klebsiella spp. showed 100% resistant to beta-lactam antibiotics (ceftazidime, cefuroxime, cefixime, ciprofloxacin, and amoxicillin-clavulanic acid). Two-resistant enteric bacteria strains, Klebsiella aerogenes B18 and Citrobacter freundii B27 obtained from Nigerian tomato clustered with Citrobacter strains in food (China), water strains (India, Poland, Malaysia), milk (Germany), and human fecal (China). CONCLUSION: Implicated multidrug-resistant enteric bacilli in retailed tomatoes can cause severe food-borne diseases which public oriented awareness, strategic farm to market surveillance are needed to be intensified.

Isolation and Screening of Extracellular PGPR from the Rhizosphere of Tomato Plants after Long-Term Reduced Tillage and Cover Crops

Plant growth promoting rhizobacteria provide an innovative solution to address challenges in sustainable agro-ecosystems, improving plant growth as well as acting as agents of biocontrol. In this study autochthonous bacteria were isolated from the rhizosphere of processing tomato plants (Solanum lycopersicum L.) cultivated with conservation agriculture practices (i.e., reduced tillage and cover crops), and evaluated for both growth-promoting activities (PGPAs), and antagonistic potential against the phytopathogenic pest Sclerotinia sclerotiorum. Considering the several activities of PGPR, we decided to structure the screening with a hierarchic approach, starting from testing the capability of fixing nitrogen. The obtained bacteria were processed through the molecular typing technique rep-PCR (Repetitive Extragenic Palindromic) in order to discriminate microbial strains with the same profiles, and identified via 16S rDNA sequencing. Thirty-eight selected isolates were screened in vitro for different activities related to plant nutrition and plant growth regulation as well as for antifungal traits. Isolated bacteria were found to exhibit different efficiencies in indoleacetic acid production and siderophore production, phosphate solubilization and biocontrol activity against the widespread soil-borne plant pathogen S. sclerotiorum. All the 38 bacterial isolates showed at least one property tested. With a view to detect the suitable candidates to be developed as biofertilizers, the selected isolates were ranked by their potential ability to function as PGPR. Thus, consortium of native PGPR bacteria inoculants may represent a suitable solution to address the challenges in sustainable agriculture, to ensure crop yield and quality, lowering the application of chemicals input.