Artificial in Vitro Synthetic Enzymatic Biosystem for the One-Pot Sustainable Biomanufacturing of Glucosamine from Starch and Inorganic Ammonia

Abstract

Glucosamine is a naturally occurring bioactive amino monosaccharide which is widely used in the food, cosmetics, and pharmaceutical industries. It is traditionally produced by acid hydrolysis/enzymolysis of chitin but suffers from possible individual allergenic risk, serious environmental pollution, and low production yield. A recent rising approach for glucosamine production is microbial fermentation using engineered microorganisms to manufacture N-acetylglucosamine, followed by acid hydrolysis of N-acetylglucosamine to glucosamine. However, this approach does not produce glucosamine in one-pot, and suffers from environmental issues caused by the acid hydrolysis process. To produce cost-competitive glucosamine with environmental sustainability, we demonstrated an artificial in vitro synthetic enzymatic biosystem comprised of five cascade enzymes for biomanufacturing glucosamine from maltodextrin and inorganic ammonia in one-pot. This nonshellfish-derived, phosphate-balanced, and coenzymefree synthetic enzymatic biosystem was optimized in terms of pH value, enzyme composition, phosphate concentration, and ammonia concentration. The optimized enzyme cocktail converted 10 g/L maltodextrin to 7.9 g/L glucosamine with a conversion efficiency of 75.8% mol/mol glucose equivalent of maltodextrin. Moreover, a simple scaling-up for this nonfermentative biomanufacturing biosystem was performed to investigate its industrial potential, giving out 23.7 g/L glucosamine from 50 g/L maltodextrin. This in vitro enzymatic platform provides a biorefinery technology for the production of glucosamine featuring predictable security, environmental friendliness, and sustainability, thereby representing a highly promising alternative approach for glucosamine production on an industrial scale.

CuS Nanoparticles Trigger Sulfite for Fast Degradation of Organic Dyes under Dark Conditions

“…The C 1S spectrum (Figure d) was deconvoluted into three peaks: (i) 284.6 eV assigned to C–C and C–H bonds of sp 2 hybridization, (ii) 285.3 eV ascribed to C–O–C bonds, and (iii) 285.6 eV attributed to C–OH, CO, and O–C–O bonds, which further confirmed the presence of starch, the capping molecule . The N 1S spectrum (Figure e) exhibited two peaks at about 400.1 and 401.4 eV, which was ascribed with the amine group (C–NH 2 ) and protonated amine group (C–NH 3 + ) suggesting the interaction of starch and ammonia. , …”

“…The C 1S spectrum (Figure 4d 41 The N 1S spectrum (Figure 4e) exhibited two peaks at about 400.1 and 401.4 eV, which was ascribed with the amine group (C−NH 2 ) and protonated amine group (C−NH 3 + ) suggesting the interaction of starch and ammonia. 42,43 Under dark conditions, the catalytic activity of CuS NPs was evaluated for the degradation of sample dyes (MB, MO, and BB) with or without SO 3 2− . We observed that the CuS NPs/SO 3…”

Wastewater-powered high-value chemical synthesis in a hybrid bioelectrochemical system

“…Since some enzymes are not commercially available in present study, the cost for the lab scale production of enzyme is used first to estimate the cost for commercial ones. In a lab scale, enzyme cost of 1 kg substrate is about $12.7-14.4 (Meng et al, 2020;Han et al, 2020). Thus, we assume that the cost of enzyme in a lab scale in general is $20/kg substrate (higher than the value in literatures) and therefore commercially is $10/kg substrate.…”

Stoichiometric Conversion of Maltose for Biomanufacturing by In Vitro Synthetic Enzymatic Biosystems

“…This emerging biosystem for biomanufacturing features several advantages over in vivo systems (microbial fermentation), including fewer side reactions and easier adjustment of reaction conditions [2] and hence often result in high product yields and fast reaction rates [3][4][5][6]. Carbohydrates such as glucose, sucrose, cellobiose, cellulose, and starch are promising substrates for in vitro synthetic enzymatic biosystems to produce hydrogen [7][8][9], bioelectricity [10][11][12], and biochemicals such as myo-inositol [4,5,13], fructose 1,6diphosphate (FDP) [14], D-allulose [6], glucosamine [15], polyhydroxybutyrate [16], and monoterpenes [17]. The first step of these in vitro biosystems is the phosphorylation of carbohydrate substrates to either glucose 1-phosphate (G1P) or glucose 6-phosphate (G6P), which are two important intermediates for biosynthesis.…”