Enzymes and biosurfactants, often referred to as “green chemicals,” play pivotal roles in enhancing the washing performance of bio-based detergents—a growing trend driven by environmentally conscious consumers. However, the widespread adoption of such bio-based detergents faces challenges, including high costs, limited efficiency, and the need for ongoing innovations. Bacillus species have long been universally acknowledged and exploited for industrial applications, and Bacillus spp. are largely differentiated from other microorganisms for their enzymatic applications, particularly in detergent production. Recent developments in bio-surfactant production by Bacillus sp. support the adoption of green detergents, and these bacterial biosurfactants are a promising source for detergent manufacturing. This article provides an overview of the current understanding of promising Bacillus species and their potential to advance and accelerate the production of bio-based detergents.

The increasing demand for industrial enzymes calls for cost-effective and sustainable production strategies. This study investigates the potential of industrial wastewater as an alternative fermentation medium for enzyme synthesis, aligning with the principles of the circular bioeconomy. Four wastewater types from Québec, Canada—beverage wastewater (BW), pulp and paper mill activated sludge (PPMS), food industry wastewater (FIW), and starch industry wastewater (SIW)—were evaluated for their potential to support protease, amylase, and lipase production using Bacillus licheniformis, Bacillus amyloliquefaciens, and Bacillus megaterium. Initial screening identified SIW as optimal for amylase production with B. amyloliquefaciens, and PPMS for protease production with B. megaterium. Optimization using the Box–Behnken design was then performed, followed by scale-up experiments in 5 L bioreactors. B. amyloliquefaciens achieved 5.73 ± 0.01 U/mL of amylase at 48 h under 40 g/L total solids, 30 °C, and a 2% inoculum size, while B. megaterium produced the highest protease of 55.41 ± 3.54 U/mL at 24 h. Lipase production remained negligible across all media and strains. These findings demonstrate the feasibility of the potential of wastewater-based enzyme production, reducing reliance on expensive synthetic substrates, mitigating environmental burdens, and contributing to the transition to a circular bioeconomy.

Bioremediation is a biological process to remove or neutralize environmental pollutants. This study was carried out to investing at the efficacy of arsenic resistant endophytic bacteria isolated from Pteris vittata, Pityrogramma calomelanos, Blenchum orientale, and Nephrolepis exaltata, which grow in a highly arsenic (As) contamination mining site in Vietnam. Their segmented roots, stems, and leaves were homogenized separately and inoculated on LB agar plates containing 5mM As(III) and As(V). A total of 31 arsenic resistant endophytic strains were selected, in which strain R2.5.2 isolated from the root of P. calomelanos had the highest arsenic resistant capability. Strain R2.5.2 tolerated up to 320 mM and 160 mM of arsenate and arsenite, respectively. The strain developed well on a media of 0.1 5% NaCl, at 20-40ºC and pH 5 9, and actively utilized most of the sugar sources. It had a high IAA biosynthesis capacity with an average concentration of 19.14 mg/L, tolerated to 0.5-16 mM concentration of Ag+, Hg2+, Co2+, Ni2+, Cu2+, Cr4+, and reduced As(V). Based on 16s rDNA, R2.5.2 was identified as Priestia megaterium. The ars C gene coding for arsenate reductase catalyzing reduction of As(V) was successfully amplified in P. megaterium R2.5.2. The selected strain may have potential use for bioremediation practice.

This study explores the potential of using paper pulp mill sludge (PPMS) as an economical substrate for producing high-value protease enzymes with an indigenous bacterial strain, Bacillus tropicus P4. Isolated directly from PPMS, B. tropicus P4 showed high protease-producing ability, approximately 134 U/mL after 48 h—more than three times the yield of the benchmark strain (B. megaterium). Among various additives tested to boost enzyme production, Tween 80 emerged as the most effective, increasing enzyme activity by more than threefold compared to the control. Scale-up experiments in bioreactors of 5 L and 150 L confirmed that B. tropicus P4 maintains high protease yields under typical cultivation conditions with minimal modifications, specifically the addition of Tween 80 (1%) and increased total solids concentration (25 g/L). In the 5 L bioreactor, enzyme production peaked at approximately 755 U/mL within 24 h, while the 150 L bioreactor consistently achieved high enzyme activity (~848 U/mL). These results support the feasibility of a simple and scalable approach for converting industrial sludge into high-value protease enzymes, contributing to resource recovery and circular bioeconomy strategies.