This study investigated the polyphenol content, antioxidant activity, and inhibition ability of mushroom tyrosinase and melanogenesis of Dendrobium tosaense (DT) extract. Ground DT was extracted using deionized water (W) or 50% ethanol (50E) at room temperature (RT) or 50 °C (50T) for 20 min. The 50T + 50E extract exhibited the highest total phenol content 47.0 ± 4.0 mg gallic acid equivalent/g DT extract, the highest level of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging 66.0 ± 3.0 mg Trolox equivalent/g DT extract, and the highest reducing power 12.00 ± 0.50 mg vitamin C equivalent/g DT extract. The RT + W extract had the highest total flavonoid content 110.0 ± 3.0 mg quercetin equivalent/g DT extract. The RT + 50E extract had the lowest half maximal inhibitory concentration 1.30 ± 0.00 mg/mL for 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging, and the lowest half maximal inhibitory concentration 6.40 ± 0.30 mg/mL for mushroom tyrosinase inhibition activity. DT extracts, especially RT + W and 50T + W, exhibited potent inhibitory effects on melanogenesis of B16/F10 cells. These results demonstrated the application potential of DT extract for skincare.

Background. Following petroleum, coffee is the second most commonly traded commodity globally. It is also a popular good with economic value, as well as value in terms of leisure and culture. However, coffee processing generates a large amount of waste, resulting in environmental concerns. Therefore, in this study, ethanol was used to extract coffee waste (coffee pulp). High-performance liquid chromatography was conducted to examine the caffeine content and chlorogenic acid content, and the antioxidant capacity (i.e., the total phenolic content, total flavonoid content, DPPH-free radical scavenging capacity, ABTS-free radical scavenging capacity, and reductive capacity) and the tyrosinase inhibition capacity of the coffee pulp extracted using ethanol were comprehensively evaluated. Results. The results showed that the coffee pulp extract obtained using 70 ethanol had the highest tyrosinase inhibition capacity, whereas that obtained using 50 ethanol had the most satisfactory antioxidant capacity (total phenolic content, total flavonoid content, DPPH-free radical scavenging capacity, ABTS-free radical scavenging capacity, and reductive capacity). Conclusion. The results revealed that coffee pulp has superior antioxidant capacity and tyrosinase inhibition capacity when extracted by ethanol. Increasing the economic value of coffee pulp can solve the environmental concerns caused by coffee waste.

Chenopodium formosanum (CF), rich in nutrients and antioxidants, is a native plant in Taiwan. During the harvest, the seeds are collected, while the roots, stems, and leaves remain on the field as agricultural waste. In this study, di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) radical scavenging ability and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging ability experiments of seeds, leaves, stems, and roots were designed using the Taguchi method (TM) under three conditions: Ethanol concentration (0–100%), temperature (25–65 °C), and extraction time (30–150 min). The result demonstrates that seeds and leaves have higher radical scavenging ability than stems and roots. Many studies focused on CF seeds. Therefore, this study selected CF leaves and optimized DPPH, ABTS, total phenol content (TPC), total flavonoid content (TFC), and reducing power (RP) through TM, showing that the predicted value of the leaf is close to the actual value. The optimized results of CF leaves were DPPH 85.22%, ABTS 46.51%, TPC 116.54 µg GAE/mL, TFC 143.46 µg QE/mL, and RP 23.29 µg VCE (vitamin C equivalent)/mL. The DPPH and ABTS of CF leaves were second only to the results of CF seeds. It can be seen that CF leaves have the potential as a source of antioxidants and help in waste reduction.

Black soldier fly (BSF) larvae efficiently convert organic residues into protein‐ and lipid‐rich biomass, with oil extracted from BSF larvae exhibiting notable antioxidant potential. This study investigated larval growth, oil yield, and antioxidant properties for four feeding substrates made from cereal byproducts: wheat bran, rice bran, sorghum grain, and red quinoa hulls. BSF larvae reared for 7 days on different substrates displayed significant differences in body size, moisture content, and oil extraction efficiency. Wheat‐bran‐fed larvae had the lowest moisture content and largest size, whereas red‐quinoa‐fed larvae exhibited the highest moisture content but smallest size. Sorghum‐fed larvae had the highest oil yield, followed by larvae fed with wheat bran, red quinoa, or rice bran. Oils extracted from larvae reared on the four substrates were analyzed for total phenolic content (TPC) and antioxidant activity using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2,2′‐azinobis‐3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assays. Oil extracted from red‐quinoa‐fed larvae had the highest TPC (79.25 ± 1.04 μg of gallic acid equivalents per gram of oil) and strongest radical scavenging abilities (IC ₅₀ for DPPH = 22.0 ± 1.1 μg/mL, IC ₅₀ for ABTS = 11.6 ± 1.0 μg/mL, and FRAP = 29.24 ± 1.00 μg of vitamin C equivalents per gram of oil), closely followed by oil extracted from rice‐bran‐fed larvae. Pearson correlations indicated that TPC strongly predicted antioxidant performance ( r = −0.995 to 0.962, p < 0.01). Red quinoa optimizes the functional quality of BSF oil. Rice bran offers a balance between oil yield and bioactivity. These findings highlight the effects of feed substrate on BSF oil properties.