Dioscorea batatas Decne (Chinese yam) has been widely cultivated in East Asia for the purposes of food and medicinal uses for centuries. Along with its high nutritional value, the medicinal value of D. batatas has been extensively investigated in association with phytochemicals such as allantoin, flavonoids, saponins and phenanthrenes. Phenanthrenes are especially considered the standard marker chemicals of the Chinese yam for their potent bioactivity and availability of analysis with conventional high performance liquid chromatography with ultraviolet detection (HPLC-UV) methods. In order to investigate how much the contents of phenanthrenes are in the actual food products provided for consumers, D. batatas tuber was peeled and separated into its peel and flesh as in the conventional processing method. A quantitative analysis using the HPLC-UV method revealed that phenanthrenes are concentrically present in the D. batatas peel, while phenanthrenes are present in the flesh under the limit of detection. The difference in the contents of phenanthrenes is estimated to have arisen the considerable difference of antioxidant potential between the peel and the flesh. The results from this study suggest the high value of the discarded biomass of the Chinese yam peel and the necessity for the utilization of the Chinese yam peel.

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Background and objectives: Sargassum miyabei Yendo, belonging to the family Sargassaceae, has been reported to have various biological effects such as anti-tyrosinase activity and anti-inflammation. However, the anti-obesity effect of Sargassum miyabei Yendo has not yet been reported. Materials and Methods: The effects of Sargassum miyabei Yendo extract (SME) on 3T3-L1 adipocytes were screened by3-(4,5)-dimethylthiazo-2-yl-2,5-diphenyltetrazolium bromide (MTT), Oil red O staining, western blot, and Real-time reverse transcription polymerase chain reaction analyses. Results: Here, we show that SME had potent 2,2’-azinobis-3-ehtlbezothiazoline-6-sulfonic acid radical decolorization (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity with half maximal inhibitory concentration (IC50) value of 0.2868 ± 0.011 mg/mL and 0.2941 ± 0.014 mg/mL, respectively. In addition, SME significantly suppressed lipid accumulation and differentiation of 3T3-L1 preadipocytes, as shown by Oil Red O staining results. SME attenuated the expression of adipogenic- and lipogenic-related genes such as peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT-enhancer-binding protein alpha (C/EBPα), CCAAT-enhancer-binding protein delta (C/EBPδ), adiponectin, adipose triglyceride lipase (ATGL), fatty acid synthase (FAS), hormone-sensitive lipase (HSL), and lipoprotein lipase (LPL). Conclusions: These findings suggest that SME may have therapeutic implications for developing a new anti-obesity agent.

The yellow‐legged hornet, Vespa velutina nigrithorax, is an invasive social wasp found in temperate regions and is recognized as a hazardous insect, as it often attacks humans and honeybees. Nidus vespae (nests of social wasps) are traditionally used as a medicinal ingredient; thus, V. v. nigrithorax may be useful as a biological resource. Extracts of Nidus vespae built by V. v. nigrithorax were examined for their antibacterial activity screening against six food‐borne pathogenic bacteria, and the ethyl acetate and butanol layer of the extract exhibited inhibitory activity against the pathogenic bacteria. We determined the antibacterial activity of Nidus vespae built by V. v. nigrithorax for the first time.

Objectives Maca (Lepidium meyenii) is a biennial herbaceous plant of family Brassicaceae with various bioactivities such as reproductive health enhancement, antifatigue, antioxidation, neuroprotection, anticancer, hepatoprotection, and immunomodulation. But studies on molecular mechanisms beyond the phenomenal physiology are rare because the putative bioactive chemical constituents, macamides, a series of unique N-benzylamides with long-chain fatty acids are difficult to isolate from the natural maca specimen. In this study, ten macamides were chemically synthesized to investigate biological mechanisms underlying the various bioactivities. Methods Macamides were synthesized from benzylamides and commercially available fatty acids adding 1,1'-carbonyl diimidazole. Nrf2 activation of macamides were measured using U2OS cells in CP0. Quantitative analysis of bioactive macamides were performed using LC-MS/MS system and synthesized standard macamides. The difference in composition of macamides among three cultivars, yellow, red and black macas was also examined. Results Three of macamides exhibited moderate nuclear factor erythroid 2-related factor 2 (Nrf2) activation was observed from cell-based assay (EC50 7.3–16.5 μM), which might account for some of the known bioactivities of maca. Quantitative analysis of macamide compositions in maca specimen using LC-MS/MS was followed, which revealed the macamides with Nrf2 activation activity consist the majority among macamides contained in maca. Conclusions Among the bioactivities that have known as the beneficial effects of maca, bioactivities related to antioxidation might be accounted for the Nrf2 activation of macamides contained in maca. Funding Sources This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (2019R1F1A1051041).