Carotenoids are lipophilic tetraterpenoid pigments produced by plants, algae, arthropods, and certain bacteria and fungi. These biologically active compounds are used in the food, feed, and nutraceutical industries for their coloring and the physiological benefits imparted by their antioxidant properties. The current global carotenoid market is dominated by synthetic carotenoids; however, the rising consumer demand for natural products has led to increasing research and development in the mass production of carotenoids from alternative natural sources, including microbial synthesis and plant extraction, which holds a significant market share. To date, microbial research has focused on C₄₀ carotenoids, but studies have shown that C₃₀ carotenoids contain similar—and in some microbial strains, greater—antioxidant activity in both the physical and chemical quenching of reactive oxygen species. The discovery of carotenoid biosynthetic pathways in different microorganisms and advances in metabolic engineering are driving the discovery of novel C₃₀ carotenoid compounds. This review highlights the C₃₀ carotenoids from microbial sources, showcasing their antioxidant properties and the technologies emerging for their enhanced production. Industrial applications and tactics, as well as biotechnological strategies for their optimized synthesis, are also discussed.

Current Topics in Lactic Acid Bacteria and Probiotics, 한국유산균프로바이오틱스학회 학술지

Luteolin is the most abundant phytochemical phenolic compound contained within peanut hulls and has broad pharmacological characteristics and high bioavailability. In this study, the extraction conditions for luteolin from peanut hulls were optimized. The effects of methanol concentration and reaction temperature on luteolin solubility were determined using the central composite design (CCD) under response surface methodology. Luteolin content within in the extracts increased with increasing temperature and organic solvent-to-water ratios. The optimal conditions for luteolin extraction were 81°C and 87.5% methanol for a predicted extraction value of 174.51 mg/100 g, which was within 1.25% of the experimental value of 172.35 mg/100 g, confirming the predicted model. Additionally, compared to conventional stirring, the luteolin content of reflux-extracted peanut hull had a higher extraction efficiency by 42.50%. The antioxidant compound contents and antioxidant capacity of the extracts were also determined, with the effects of temperature and solvent concentration increasing along with the extracted luteolin. In this study, CCD optimized the conditions for obtaining luteolin from peanut hulls, suggesting that the improved extraction efficiency of the bioactive compound can expand the use of peanut shells in the nutraceutical and food industries.

Current Topics in Lactic Acid Bacteria and Probiotics, 한국유산균프로바이오틱스학회 학술지