Sustainability potentials of novel laccase tinctures from Stenotrophomonas maltophilia BIJ16 and Bordetella bronchiseptica HSO16: From dye decolourization to denim bioscouring

John O Unuofin

doi:10.1016/j.btre.2019.e00409

Abstract

The aim of this present study was to investigate the environmental proficiency of two laccase producing bacterial strains, Hb16c and Berl11b2. Here, laccases, which were secreted in media containing environmental wastes, were characterized for biochemical and kinetic novelty and applied in the decolourization of some synthetic dyes and subsequently, denim bleaching. The laccases exhibited enhanced pH-, thermo-, psychro-, metal-, halo-, and surfacto-tolerance, eliciting residual activities of at least ca. 71%. Thereafter, the enzymes were able to decolourize novel high concentrations of synthetic dyes (0.2% w v−1) at 56 h of incubation, and also elicit a mediator-assisted perpetual wash up and decolourization of indigo pigment from fabric under 6 h. The outcomes observed in this study therefore warrant the adoption of these isolates for applications toward a sustainable and total environment through production of fine biochemicals, and the minimization of environmental wastes.

Highlights

According to the United Nations (UN), under the United Nations Development Programme (UNDP), the sustainable development goals (SDG) or Global Goals, which were inaugurated in January 2016, were intended for the alleviation or extermination of overarching global challenges, such as: poverty, climate and environmental degradation, inequality, injustice, feuds and hostilities, worldwide
The sustainability annals of the present study had begun from preceding studies, which had expounded the isolation of some remarkable laccase producing bacteria from some environmental wastes and detritus in milieus proposed as ideal mesocosms [4; Unuofin et al unpublished], and the subsequent valorization of inexpensive agroindustrial wastes as feedstock for the tremendous outputs of laccase, using the auspicious bacterial strains that had been identified [2,3]
Some unique biochemical properties of the laccase secretions appraised in this study have been outlined in Tables 2a and 2b

Summary

Introduction

According to the United Nations (UN), under the United Nations Development Programme (UNDP), the sustainable development goals (SDG) or Global Goals, which were inaugurated in January 2016, were intended for the alleviation or extermination of overarching global challenges, such as: poverty, climate and environmental degradation, inequality, injustice, feuds and hostilities, worldwide. Unuofin / Biotechnology Reports 25 (2020) e00409 the espousal of bespoke laccase-based products for denim bleaching by enzymes companies, such as Novozyme (Denmark), Prozyme LAC (China) Hypozyme (USA), who have constantly produced fungal laccases, and MetGen (Finland), who launched the first commercial bacterial laccase, Metzyme, has motivated for the heuristic search for sustainable sources of laccase production, and the sustainability evaluation of laccase application In this regard, this study aimed at presenting the life cycle assessment of some bacterial laccases, which had been produced from some environmental wastes [2,3], in the decolourization of some synthetic dyes and the bleaching of indigo stained denims. Especial focus was devoted to the novel characteristics exhibited by these secretions, and a molecular snapshot of multi-homologous laccase coding genes was inferred, just we had discovered in a previous study [4]

Objectives

Methods

Results

Conclusion