Bast fiber plants require a post-harvest process to yield useable natural cellulosic fibers, denoted as retting or degumming. It encompasses the degradation of the cell wall’s non-cellulosic gummy substances (NCGs), facilitating fibers separations, setting the fiber’s quality, and determining downstream usages. Due to the inconvenience of traditional retting practices, bacterial inoculum and enzyme applications for retting gained attention. Therefore, concurrent changes of agroclimatic and socioeconomic conditions, the conventional water retting confront multiple difficulties, bast industries become vulnerable, and bacterial agents mediated augmented bio-retting processes trying to adapt to sustainability. However, this process’s success demands a delicate balance among substrates and retting-related biotic and abiotic factors. These critical factors were coupled to degrade bast fibers NCGs in bacterial retting while holistically disregarded in basic research. In this study, a set of factors were defined that critically regulates the process and requires to be comprehended to achieve optimum retting without failure. This review presents the bacterial strain characteristics, enzyme potentials, specific bast plant cell wall’s structure, compositions, solvents, and interactions relating to the maximum NCGs removal. Among plants, associated factors pectin is the primary biding material that determines the process’s dynamics, while its degree of esterification has a proficient effect through bacterial enzymatic degradation. The accomplished bast plant cell wall’s structure, macerating solvents pH, and temperature greatly influence the bacterial retting process. This article also highlights the remediation process of water retting pollution in a biocompatible manner concerning the bast fiber industry’s endurance.

A degumming approach is used in this paper with alkalophilic pectinase-producing bacteria (APPB) and two sources of water solvents to address the existing conventional water retting complexities of kenaf. The incorporation of APPB was confirmed based on their retting feasibilities and multiple cell-wall-degrading enzymatic delicacy. The combinations of APPB with seawater offered retting achievements within six-day retting in non-sterile conditions. These retting niches showed maximum (14.67 U/mL) pectinase activity with fiber separation feasibilities of 4.75 Fried test score. The yielded fiber composition analysis showed a higher cellulose composition (84.65%) and the least amount of hemicellulose, pectin, and ligneous gummy substances. The transmission electron microscopy scan of the yielded fibers showed smooth fiber surfaces, 84.20 µm fiber diameter, and 7.65 g/tex fine fiber compared with uninoculated and combinations of freshwater treatments. The FTIR spectra revealed the cellulosic discrepancies of the retting treatments by monitoring O-H and C=O stretching at ~3300 cm−1 and ~1730 cm−1 wavenumbers. These findings are compelling to yield kenaf fibers of quality considering the existing retting difficulties.

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