Screening and Molecular Identification of Novel Pectinolytic Bacteria from Forest Soil

Abstract

Pectinases are a group of enzymes with broad application, including in plant fiber processing, pectic wastewater treatment, paper pulping, fruit juice extraction, and clarification. With an increasing industrial demand for these enzymes, it is useful to isolate organisms that produce large amounts of pectinase and possess wide ranges of stability factors like temperature and pH. In this study, 17 out of 29 bacteria (58.62%) from forest soil samples were pectinolytic. However, only four bacteria (S-5, S-10, S-14, and S-17) showed high pectin hydrolysis zones (ranging from 0.2 cm to 1.7 cm). These four bacteria were identified based on colony morphology, microscopic characterization, biochemical characteristics, and 16S rDNA sequencing. They were designated as Streptomyces sp. (S-5, S-14), Cellulomonas sp. (S-10), and Bacillus sp. (S-17). Interestingly, bacteria showed cellulase and xylanase activity in addition to pectinase. The quantitative assay for pectinase activity of the four isolates provided proof that they are pectinase producers and can be considered potential candidates for industrial uses. The crude enzyme extracts of these bacteria are applicable in oil and juice extraction from sesame seeds and apples, respectively.

Optimization of multiple enzymes production by fermentation using lipid-producing Bacillus sp.

“…The presence of a relative enzyme hydrolyzes the substrate around the colony, and a clear hydrolysis zone around the colony is observed. However, the substrate not hydrolyzed by relative enzymes forms a complex and does not show a clear zone ( Soares et al, 1999 ; Meddeb-Mouelhi et al, 2014 ; Shrestha et al, 2021b ; Al Mousa et al, 2022 ). On this basis, the bacterium was pectinase, amylase, cellulase, and xylanase producer.…”

“…Samples from inoculated flasks were collected at regular intervals of 24 h, and enzyme activities were assayed and compared. Pectinase activity was calculated by measuring the reducing sugar content released from the substrate following the 3,5-dinitrosalicylic acid (DNS) method ( Miller, 1959 ), as mentioned in a previous study ( Shrestha et al, 2021b ). In brief, 10 μl of crude enzyme extract was added to 20 μl of 1% citrus pectin solution as a substrate solution in the wells of a microplate, incubated in a 50°C water bath for 10 min, cooled, and 60 μl of DNS reagent was added.…”

Effect of Fermentation Response on Biosynthesis of Endopolygalacturonase by Utilizing Polymeric Substrates of Agricultural Origin from a Potent Strain of Bacillus

“…Similarly, Adeyefa and Ebuehi [33] also reported the production of pectinase enzyme by Bacillus subtilis strongly supporting our findings. Some novel pectinolytic bacteria were screened and identified by gene sequencing by Shrestha [34].…”

Isolation and characterization of exopectinase from Bacillus licheniformis FMB9 isolated from agricultural soil

“…They are classified into three groups, protopectinases, esterase, and depolymerases. 39 Protopectinases break down protopectin to soluble pectin, Esterase which removes methoxyl and acetyl esters from pectin forming polygalacturonic acid and Depolymerases which breakdown α-(1 → 4)-glycosidic bonds in units either by hydrolysis or by trans elimination. 38,40 Most of the polygalacturonase enzymes stimulate the rate of hydrolysis at an ideal pH ranging from 3.5 to 5.5 with a suitable temperature that ranges from 30 to 50°C.…”