Separation of phenolic compounds from roselle (Hibiscus sabdariffa) calyces with aqueous two-phase extraction based on sodium citrate and polyethylene glycol or acetone

Purification of Coffee Polyphenols Extracted from Coffee Pulps (Coffee arabica L.) Using Aqueous Two-Phase System

Coffee pulp is an abundant residue from the coffee industry, but it still contains large amounts of valuable compounds such as polyphenols. The extraction of polyphenols from coffee pulp by the conventional method is accompanied by contaminated compounds. This study, therefore, applied an aqueous two-phase system consisting of different ratios of ethanol/ammonium sulfate to eliminate impurities from coffee-pulp crude extract. The purification efficiency was evaluated via total polyphenol content, antioxidant activity and two major polyphenols in coffee pulps including chlorogenic acid and caffeic acid. Results showed that phenolic compounds mostly predominated in the alcohol-rich phase in which the antioxidant activity was greatly increased after the purification process. Compared to un-purified crude-coffee extract, the antioxidant activity of the purified samples increased approximately 34%, which was assumed to occur due to the slight increase of chlorogenic acid and caffeic acid. Fourier-transform infrared spectroscopy supported the effectiveness of the purification process by eliminating some impurities.

Influence of different PEG/salt aqueous two-phase system on the extraction of 2,3-butanediol

The production of 2,3-butanediol (2,3-BDO), a dialcohol of great interest for the food, chemical, and pharmaceutical industry, through the fermentation of biomass, is a sustainable process strategic position for countries with abundant biomass generated by the agribusiness. However, the downstream process of 2,3-BDO is onerous due to the complexity of fermentation broth and the physical-chemical characteristics of the 2,3-BDO. This study investigated the feasibility of 2,3-BDO extraction from model aqueous solutions using aqueous two-phase systems (ATPS). A central composite rotational design (CCRD) was employed to evaluate different ATPS compositions and the influences on the 2,3-BDO recovery and partition coefficient. The polyethylene glycol (PEG) and different concentrations of sodium citrate, ammonium sulfate, and potassium phosphate were investigated. The concentration of salt and PEG in the ATPS was identified as the most significant factors influencing the recovery and partition coefficient of 2,3-BDO. The recovery of 2,3-BDO reached 94.5% and was obtained when the system was composed of 36.22% (w/w) of PEG 4000 and 4.47% (w/w) of potassium phosphate. The results indicate that ATPS based on PEG-salt has a high potential for industrial application, using mild conditions and a simple process for recovering and purifying the 2,3-BDO produced from microbiological synthesis.

Bioproduction process of natural products and biopharmaceuticals: Biotechnological aspects

Decades of research have been put in place for developing sustainable routes of bioproduction of high commercial value natural products (NPs) on the global market. In the last few years alone, we have witnessed significant advances in the biotechnological production of NPs. The development of new methodologies has resulted in a better understanding of the metabolic flux within the organisms, which have driven manipulations to improve production of the target product. This was further realised due to the recent advances in the omics technologies such as genomics, transcriptomics, proteomics, metabolomics and secretomics, as well as systems and synthetic biology. Additionally, the combined application of novel engineering strategies has made possible avenues for enhancing the yield of these products in an efficient and economical way. Invention of high-throughput technologies such as next generation sequencing (NGS) and toolkits for genome editing Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated 9 (CRISPR/Cas9) have been the game changers and provided unprecedented opportunities to generate rationally designed synthetic circuits which can produce complex molecules. This review covers recent advances in the engineering of various hosts for the production of bioactive NPs and biopharmaceuticals. It also highlights general approaches and strategies to improve their biosynthesis with higher yields in a perspective of plants and microbes (bacteria, yeast and filamentous fungi). Although there are numerous reviews covering this topic on a selected species at a time, our approach herein is to give a comprehensive understanding about state-of-art technologies in different platforms of organisms.