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Ginsenosides Rb₁ and Rd are the two main types of ginsenosides in Panax ginseng and have been used as an additive to against alopecia. However, the mechanisms involved are largely unknown. To determine how ginsenosides prevent hair loss, we topically applied protopanaxadiol-type ginsenosides Rb₁ and Rd over the shaved skin of B57CL/6 mice, and monitored and assessed them for 35 days. We then investigated the effects of ginsenosides on cell genesis in different phases of adult hair follicles (HFs), using 5-bromo-2'-deoxyuridine as a marker for dividing cells. Moreover, p63, a specific marker and a major regulator of keratinocyte progenitor cells of the multi-layered epithelia, was detected in epidermis. Results indicated that treatment with ginsenosides Rb₁ and Rd increased cell proliferation in both anagen and telogen of HFs. However, it had no significant effect on the survival of cells in the bulge and upper follicle region. Investigation of p63 demonstrated that up-regulation of p63 expression in the matrix and outer root sheath might be one of the mechanisms by which ginsenosides Rb₁ and Rd promote cell proliferation in HFs. Our study reveals a novel mechanism by which ginsenoside promotes hair growth through p63 induction in follicular keratinocytes and indicates that ginsenosides Rb₁ and Rd might be developed as a therapeutic agent for the prevention of hair loss., (Copyright © 2012 John Wiley & Sons, Ltd.)

In this study, rare ginsenoside Rf was transformed into 20(S)-protopanaxatriol (PPT(S)) by glycosidase from Aspergillus niger. By investing the reaction conditions, the optimal conditions were obtained, as follows: pH 5.0, temperature 55 degrees C, and substrate concentration 1.25 mmol/l. Under optimal conditions, PPT(S) (1.13 micromol) prepared from 1.25 mumol Rf showed a higher yield (90.4%). The enzymatic reaction was analyzed by reversed-phase HPLC, suggesting the transformation pathway: Rf-->Rh1(S)-->PPT(S).

A high-performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) has been developed to identify and quantify 19 ginsenosides (Rg(1), Re, Rf, Rb(1), Rc, Rb(2), Rd, F(4), Rg(6), Rk(3), Rh(4), 20(S)-, 20(R)-Rg(3), 20(S)-, 20(R)-Rs(3), Rk(1), Rg(5), Rs(4), and Rs(5)) in black ginseng (BG, Korean white ginseng that was subjected to nine cycles of steam treatment). Ultrasonication is employed for sample preparation, and the analysis is achieved on a Discovery C(18) column using gradient elution of CH(3)CN-H(2)O-CH(3)COOH without buffer in 40min. The method was validated by linearity (r(2)> or =0.9994), precision (92.0-107.5%), intra- and inter-day accuracy (R.S.D.<3.21%), and limit of detection (LOD< or =93ng). The quantification method was applied to analyze the composition of ginsenosides in Korean white, red, and black ginsengs. During the preparatory process of BG, ginsenosides transform into constituents of low polarity by hydrolysis, isomerization, and dehydration at C-20, and hydrolysis also occurs at C-3 or C-6. The validated HPLC method is expected to provide the basis for the quality assessment of ginseng products.

To optimize ginsenosides hydrolyzing beta-glucosidase production from Aspergillus niger, response surface methodology was carried out in two stages. The Plackett-Burman design was achieved to screen the important variables that influence beta-glucosidase production. Among 10 variables (wheat bran, soybean powder, CaCl(2), ginsenosides, KH(2)PO(4), MgSO(4), polyethylene glycol (PEG), medium volume, inoculum size, and stirring speed), it was found that wheat bran, KH(2)PO(4), and stirring speed had significant effect on beta-glucosidase activity due to very low p-values (p<0.05). Subsequently, wheat bran, KH(2)PO(4), and stirring speed were further optimized using central composite design. The optimal beta-glucosidase production was predicted to be 4650.14 U/ml with the combination of factors (wheat bran, 34.51 g/l; KH(2)PO(4), 1.78 g/l; stirring speed, 161.60 rpm/min). Finally, under optimal fermentation conditions, ginsenoside Rb(1) was converted to Rd and F(2) by A. niger within 10 min. Little compound K was detected at 30 min, and finally F(2) was completely transformed to compound K within 8 h. The putative conversion pathway of Rb(1) by A. niger was Rb(1), Rd, F(2), and compound K.