Fermentative lactic acid production from coffee pulp hydrolysate using Bacillus coagulans at laboratory and pilot scales

Abstract

In this study, the lignocellulosic residue coffee pulp was used as carbon source in fermentative l(+)-lactic acid production using Bacillus coagulans. After thermo-chemical treatment at 121°C for 30min in presence of 0.18molL(-1) H2SO4 and following an enzymatic digestion using Accellerase 1500 carbon-rich hydrolysates were obtained. Two different coffee pulp materials with comparable biomass composition were used, but sugar concentrations in hydrolysates showed variations. The primary sugars were (gL(-1)) glucose (20-30), xylose (15-25), sucrose (5-11) and arabinose (0.7-10). Fermentations were carried out at laboratory (2L) and pilot (50L) scales in presence of 10gL(-1) yeast extract. At pilot scale carbon utilization and lactic acid yield per gram of sugar consumed were 94.65% and 0.78gg(-1), respectively. The productivity was 4.02gL(-1)h(-1). Downstream processing resulted in a pure formulation containing 937gL(-1)l(+)-lactic acid with an optical purity of 99.7%.

From Upstream to Purification: Production of Lactic Acid from the Organic Fraction of Municipal Solid Waste

“…The final volume of the fermentation was 35.6 L (due to base addition) with a LA concentration of 58.7 g L −1 and, by the end of the downstream, the product was 1.06 L of a solution containing 930 g L −1 . Therefore, LA overall recovery yield was 45%, a value comparable to previous reports in the literature that used organic and agricultural residues [16,22]. In this case, most of the LA losses (about 60%) were the result of the micro-and nanofiltration steps.…”

Valorising Agro-industrial Wastes within the Circular Bioeconomy Concept: the Case of Defatted Rice Bran with Emphasis on Bioconversion Strategies

“…Various acids (organic and inorganic) have been proposed in the literature, such as sulphuric acid, hydrochloric acid, phosphoric acid, and citric acid, as efficient means for hemicellulose solubilisation [33]. Dilute sulphuric acid hydrolysis has been successfully employed in a variety of biomasses, including sugar beet pulp [34], coffee pulp and coffee mucilage [35,36] among others. The main disadvantage of this method is the production of inhibitory compounds (acetic acid, furfural, 5-hydrolxymethylfurfural (HMF)) that could hamper the fermentability of the produced hydrolysate.…”

“…Companies like Galactic and NatureWorks have already included agricultural and food wastes in their production line [61]. Among the different renewable feedstocks proposed in the literature for LA production, such as municipal solid wastes [62], coffee byproducts [35,36] and food wastes [63][64][65], many researchers have also attempted to produce LA from DRB using various microbial strains.…”

Techno-Economic Analysis of Bio-Based Lactic Acid Production Utilizing Corn Grain as Feedstock

“…U.S. Department of Energy's National Laboratories have also identified lactic acid as one of the few promising platform chemicals that can be further converted to other important chemicals, such as acrylic acid, propylene glycol, acetaldehyde, and 2,3-pentanedione and polymers such as poly-lactic acid [3]. Bio-based lactic acid can be produced from different sources, including agricultural residues and food waste [4][5][6][7][8]. Lactic acid production using sugarcane bagasse feedstock showed that cellulose-based processes have larger lactic acid production rates and lower production costs than hemicellulose-based processes; and gypsum-free scenarios had the lowest production costs [9].…”