Extraction and Concentration of Waste Pueraria lobata Stems with Antioxidants and Anti-Melanogenesis Activity as a Novel Skin Whitening Agent for Natural Cosmetic Prototypes.

The root of Pueraria lobata (Willd.) is used commercially in different products, including dietary supplements, cosmetics, and teas, but its stem part is rarely used and studied. Therefore, this study evaluated the antioxidant and anti-melanogenesis activities of the bioactive fraction of P. lobata stem and investigated whether the activated carbon decolorization technique would have an impact on its activity and chemical composition. We observed that the dichloromethane fraction of P. lobata stem (DCM-PLS) has excellent antioxidant and anti-melanin synthesis activity at a concentration of 50 µg/mL. For the investigation of the anti-melanogenesis mechanism, we evaluated the mRNA expression of tyrosinase, which was depressed by the DCM-PLS. Daidzin was identified as the main active ingredient in DCM-PLS by using a high-performance liquid chromatography-diode array detector-hyphenated with tandem mass spectrometry. In addition, the activated carbon decolorization technology has no negative impact on the main components and bioactivity of DCM-PLS. DCM-PLS also did not induce any skin response in the human skin safety test. Collectively, DCM-PLS could be used as a natural type of skin-whitening agent in skin care products.

Phenolic Profile and Fingerprint Analysis of Akebia quinata Leaves Extract with Endothelial Protective Activity.

In contrast to the stem and fruit of Akebia quinata, A. quinata leaves as a source rich in phenolic compounds with potentially beneficial pharmacological activities have been largely overlooked. To develop and use A. quinata leaves as a resource, we evaluated its potential as a cardiovascular-protective agent. Herein, we investigated the effects and potential mechanisms of A. quinata leaves extract on lipopolysaccharide (LPS)-induced inflammatory responses in human umbilical vein endothelial cells. We found that A. quinata leaves extract pretreatment of 10 µg/mL significantly attenuated LPS-induced protein expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1. Furthermore, this extract also suppressed LPS-induced phosphorylation of nuclear factor-κB p65. In order to elucidate the chemical profiles of the samples, the HPLC fingerprint was established, and prominent peaks were identified via HPLC-electrospray ionization-mass spectrometry. Multivariate statistical analyses, including hierarchical cluster analysis, principal component analysis, and partial least-squares discriminant analysis, were performed to evaluate the clustering of the samples. It was found that isochlorogenic acid C was a key marker for the classification of A. quinata leaves from the Gongju and Muju city in Korea. Collectively, this study not only suggested the potential of A. quinata leaves as a novel therapeutic candidate for inflammatory cardiovascular disease but also developed a quality control method for A. quinata leaves, which could help to expand the application of A. quinata.

Effect of citric acid and heat treatment on the content of less-polar ginsenosides in flower buds of Panax ginseng.

Ginseng flower bud (GFB), as an inexpensive part of Panax ginseng, attracted significant attention as a beneficial functional food with medicinal potentials due to its high content of ginsenosides. A few studies focused on the utilization of heat treatment and citric acid treatment to process ginseng flowers, converting its polar ginsenosides into rare ginsenosides to improve its biological activities. Thus, in this study, we compared the changes of ginsenosides in GFB after citric acid and heat treatment by HPLC method. The results revealed that less-polar ginsenoside, Rg6 and F4, increased to 1.01 and 0.27% by heat treatment, respectively. Further, ginsenoside F2 increased to 1.13% with 1 M citric acid treatment. Furthermore, based on the combination of these two processing methods for the first time, the conversion rate of less-polar ginsenosides surged to 80%. The content of ginsenoside Rg3(s) and Rg5 increased to 1.509 and 1.871%, respectively, by simultaneous heat and citric acid treatment. Therefore, a processing approach that simultaneously performs heat and citric acid treatments has been proposed, and this considerably inexpensive and convenient processing method could be applied to the processing of GFBs and produce less-polar ginsenosides.

Anti-Wrinkle Effect of Isatis indigotica Leaf Extract: Evaluation of Antioxidant, Anti-Inflammation, and Clinical Activity.

Isatis indigotica leaf is an oriental herbal medicine that has been known for various pharmacological effects. However, its anti-wrinkle activity has not been fully evaluated. Therefore, we evaluated the anti-wrinkle effect of I. indigotica leaf extract on human skin. The purified extract inhibited 85.4% of 2,2-diphenyl-1-1picrylhydrazyl and 72.2% of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radicals at a concentration of 1 mg/mL. Nitrite production was reduced by 30% after treatment with 50 µg/mL of extract. Three fractions from the extract downregulated the mRNA expression of matrix metalloproteinase-1 and -3 and upregulated the expression of interleukin 4. Among the three fractions, fraction 2 exhibited the highest activity. The major component of the extract was identified as 3,4,5-trimethoxycinnamic acid by liquid chromatography coupled with mass spectrometry. Molecular docking was conducted to predict the binding mechanism of 3,4,5-trimethoxycinnamic with matrix metalloproteinase-1 and -3, and their binding energies were -5.20 and -4.89 kcal/mol, respectively. In a clinical trial, five roughness values of visiometer and visual score were significantly reduced in treated groups compared with the placebo group after 8 weeks. I. indigotica leaf extract inhibits wrinkle formation, and could be a potential anti-wrinkle agent. This is the first clinical trial demonstrating its anti-wrinkle activity.

Evaluation of Anti-Melanogenesis Activity of Enriched Pueraria lobata Stem Extracts and Characterization of Its Phytochemical Components Using HPLC-PDA-ESI-MS/MS.

The root of Pueraria lobata (Willd.) is a widely used herbal medicine worldwide, whereas the stem of the plant is discarded or used as feed for livestock. To reuse and exploit the stem of P. lobata as a resource, we investigated its potential as a skin-whitening agent. We found that the developed, enriched P. lobata stem (PLS) extract significantly inhibited melanin production in the 3-isobutyl-1-methylxanthine-induced B16/F10 cells at a concentration of 50 µg/mL. To further confirm the mechanism of the antimelanogenic effect of the enriched PLS extracts, we examined the mRNA expression of tyrosinase, which was suppressed by the extracts. To standardize and implement effective quality control of the enriched PLS extracts, its major chemical constituents were identified by high-performance liquid chromatography-photodiode array-electrospray ionization-mass spectrometry. In total, 12 constituents were identified. In silico analysis showed that the main constituents, puerarin and daidzin, had excellent binding affinities for human tyrosinase. Collectively, our results suggest that the PLS extracts could be used as anti-pigmentation agents.