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Plant natural products are a seemingly endless resource for novel chemical structures. However, their extraction often results in high prices, fluctuation in both quantity and quality, and negative environmental impact. The latter might result from the extraction procedure but more often from the high amount of plant biomass required. With the advent of synthetic biology, producing natural plant products in large quantities using yeasts as hosts has become possible. Here, we focus on the recent advances in metabolic engineering of the yeasts species Saccharomyces cerevisiae and Yarrowia lipolytica for the synthesis of ginsenoside triterpenoids, namely, dammarenediol-II, protopanaxadiol, protopanaxatriol, compound K, ginsenoside Rh1, ginsenoside Rh2, ginsenoside Rg3, and ginsenoside F1. A discussion is provided on advanced synthetic biology, bioprocess strategies, and current challenges for the biosynthesis of ginsenoside triterpenoids. Finally, future directions in metabolic and process engineering are summarized and may help reify sustainable ginsenoside production.

Acyl-CoA-binding protein (ACBP) is an important protein with a size of about 10 kDa. It has a high binding affinity for C12–C22 acyl-CoA esters and participates in lipid metabolism. ACBP and its family of proteins have been found in all eukaryotes and some prokaryotes. Studies have described the function and structure of ACBP family proteins in mammals (such as humans and mice), plants (such as Oryza sativa, Arabidopsis thaliana, and Hevea brasiliensis) and yeast. However, little information on the structure and function of the proteins in filamentous fungi has been reported. This article concentrates on recent advances in the research of the ACBP family proteins in plants and mammals, especially in yeast, filamentous fungi (such as Monascus ruber and Aspergillus oryzae), and fungal pathogens (Aspergillus flavus, Cryptococcus neoformans). Furthermore, we discuss some problems in the field, summarize the binding characteristics of the ACBP family proteins in filamentous fungi and yeast, and consider the future of ACBP development.

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It is well-known that excessive cholesterol leads to hypercholesterolemia, arteriosclerosis, coronary heart disease, stroke, and other diseases, which seriously threatens human health. Lactobacillus, a prokaryote, is reported to utilize cholesterol in the environment. However, little research focuses on the cholesterol utilization by eukaryote. Hence, the objectives of the present study were to investigate the mechanism of cholesterol utilization by the eukaryote and determine the role of oxysterol binding protein in this process. Our results showed for the first time that Aspergillus oryzae, a food-safe filamentous fungus, can utilize cholesterol efficiently. Our results also demonstrated that cholesterol utilization by A. oryzae might promote the conversion of ergosterol to ergosterol peroxide. Osh3, an oxysterol binding protein, can bind sterols (e.g., cholesterol, ergosterol, and ergosterol peroxide) and plays an important role in sterols transportation. This research is of considerable significance for developing low-fat food and cholesterol-lowering probiotics.