Third-generation L-Lactic acid production by the microwave-assisted hydrolysis of red macroalgae Eucheuma denticulatum extract

Emerging technologies for conversion of sustainable macroalgal carrageenan biomass into L-lactic acid: A state-of-the-art review

“…While ED species is cultivated mainly for the extraction of iotacarrageenan phycocolloid, a thickening and emulsifying agent in food industries and a source of human food [23]. Besides being utilized for human consumption, there is a growing opportunity to produce biopolymers from i-carrageenan attributed to their high carbohydrate content, approximately 85.62 ± 0.38 wt% dry weight basis [6,24]. i-carrageenan is a heterogenous sulfated galactan that typically consists of repeating ester sulfate 3,6-anhydrogalactose and D-galactose which showed suitability as feedstock for carbohydrates-based biorefinery [6].…”

“…Besides being utilized for human consumption, there is a growing opportunity to produce biopolymers from i-carrageenan attributed to their high carbohydrate content, approximately 85.62 ± 0.38 wt% dry weight basis [6,24]. i-carrageenan is a heterogenous sulfated galactan that typically consists of repeating ester sulfate 3,6-anhydrogalactose and D-galactose which showed suitability as feedstock for carbohydrates-based biorefinery [6]. The hydrolysis process converts i-carrageenan into galactose, and it is further valorized or fermented using lactic acid bacteria to produce 3G L-LA.…”

“…Recently, PLLA application has seen tremendous growth in various fields, including packaging, biomedical applications (implants, bone fixation, and sutures), printing filament, and regulated drug delivery [5]. Further, the annual production volume of PLLA worldwide had increased by approximately 35% in 2020, corresponding to 395 kilotons as compared to 293 kilotons in 2019 [6]. PLLA is a type of biodegradable and aliphatic polymer of L(+)-lactic acid (L-LA), which is produced via ring-opening polymerization of L-LA; while L-LA can be derived from carbohydrate-rich renewable resources such as starchy materials, cellulosic materials, and agricultural wastes through a biotechnological approach using lactic acid bacteria (LAB) for microbial fermentation [7].…”

Review - New prospect of algae for sustainable production of lactic acid: Opportunities and challenges

“…The pretreatment reduces the crystallinity and degree of polymerization, leading to efficient interaction of enzymes or microbes and enhance enzymatic digestibility of the cellulose. Several reports have revealed that pretreatment of biomass enhanced the production yield in contrast to untreated biomass [31,[34][35][36][37][38]. The complex sugars extracted from algae biomass is further degraded into monosaccharides through hydrolysis process (e.g.…”

“…The details of some studies of the production of lactic acid from algae are tabulated in Table 3. As an example, both components (Carrageenan and Cellulose) in red algae, Eucheuma denticulatum are good sources to produce lactic acid as they contain high concentration of reducing sugar after hydrolysis steps [37,38]. Furthermore, to promote the zero-waste concept in biorefinery processes, the remnant biomass from the lactic acid production can be utilized for algae-biochar production through pyrolysis process.…”