Biocatalyst Potential of Cellulose-Degrading Microorganisms Isolated from Orange Juice Processing Waste

Abstract

Cellulases can be applied as macerating and peeling enzymes in the orange juice processing industry. In this work, indigenous cellulose-degrading microorganisms were isolated from orange juice processing waste through successive enrichment procedures using carboxymethyl cellulose (CMC) as the sole carbon source. A total of 24 microbial isolates were screened for their ability to grow in CMC liquid medium, resulting in the selection of seven isolates. The latter were further assessed by determining their endo-1,4-β-d-glucanase, exo-1,4-β-d-glucanase, and β-1,4-d-glucosidase activities, of which their respective activities were as high as 3.89, 10.67, and 10.69 U/mg protein. All cellulose-degraders selected belonged to the genus Paenibacillus, although to distinct operational taxonomic units related to P. xylanexedens, P. tundrae, and P. pabuli (operational taxonomic unit—OTU#1) and to P. wynnii, P. odorifer, and P. donghaensis (OTU#2) spectrum. Regarding the cellulase activities of the orange juice processing waste, endo-1,4-β-d-glucanase activity (4.00 ± 0.11 U/g) was exerted only extracellularly, whereas exo-1,4-β-d-glucanase (2.60 ± 0.19 U/g) and β-1,4-d-glucosidase (5.69 ± 0.23 U/g) activities were exhibited both extracellularly and intracellularly. In conclusion, orange juice processing waste can be considered as a valuable source for the isolation of cellulose-degrading microbiota with potential uses in beverage industry, solid state fermentation and energy production.

Improved Sugar Recovery from Orange Peel by Statistical Optimization of Thermo-Alkaline Pretreatment

“…Enzymes are required to hydrolyze carbohydrates, such as cellulose and hemicellulose, into monosaccharides [33]. In particular, in an orange peel, cellulase hydrolyzes β-1,4glycosidic bonds into cellulose and cellobiase hydrolyzes cellobiose or oligosaccharides from the non-reducing ends to glucose [34]. Xylanase is used for hydrolysis of xylan, which is a xylose biopolymer [35].…”

Fabrication of Functional Bioelastomer for Food Packaging from Aronia (Aronia melanocarpa) Juice Processing By-Products

“…The fruit juice processing industry has become one of the largest markets in the agro-industrial sector [8]. Juice processing by-products are usually buried directly in the soil, which causes serious environmental pollution [9].…”

Green Production and Biotechnological Applications of Cell Wall Lytic Enzymes

“…The presence of these materials in juice negatively affects the quality of the product and lowers user demand. Cellulases, hemicellulases, and pectinases are employed to degrade these polysaccharides, thus clarifying the juice and increasing the quality of such products [150,151]. During extraction of olive oil, continuous mixing is necessary since it allows the oil droplets to fuse to each other, increasing the oil yield.…”