Quality evaluation of Angelicae acutilobae radix: individual differences and localization of (Z)-ligustilide in Angelica acutiloba root

Kampo herbal ointments for skin wound healing

The management of skin wound healing problems is a public health issue in which traditional herbal medicines could play a determining role. Kampo medicine, with three traditionally used ointments, provides interesting solutions for these dermatological issues. These ointments named Shiunkō, Chuōkō, and Shinsen taitsukō all have in common a lipophilic base of sesame oil and beeswax from which herbal crude drugs are extracted according to several possible manufacturing protocols. This review article brings together existing data on metabolites involved in the complex wound healing process. Among them are representatives of the botanical genera Angelica, Lithospermum, Curcuma, Phellodendron, Paeonia, Rheum, Rehmannia, Scrophularia, or Cinnamomum. Kampo provides numerous metabolites of interest, whose content in crude drugs is very sensitive to different biotic and abiotic factors and to the different extraction protocols used for these ointments. If Kampo medicine is known for its singular standardization, ointments are not well known, and research on these lipophilic formulas has not been developed due to the analytical difficulties encountered in biological and metabolomic analysis. Further research considering the complexities of these unique herbal ointments could contribute to a rationalization of Kampo's therapeutic uses for wound healing.

Elucidation of Chemical Interactions between Crude Drugs Using Quantitative Thin-Layer Chromatography Analysis

To elucidate the interactions between crude drugs in Kampo medicines (traditional Japanese medicines), it is important to determine the content of the constituents in a cost-effective and simple manner. In this study, we quantified the constituents in crude drug extracts using thin-layer chromatography (TLC), an inexpensive and simple analytical method, to elucidate the chemical interactions between crude drugs. We focused on five crude drugs, for which quantitative high-performance liquid chromatography (HPLC) methods are stipulated in the Japanese Pharmacopoeia XVIII (JP XVIII) and compared the analytical data of HPLC and TLC, confirming that the TLC results corresponded with the HPLC data and satisfied the criteria of JP XVIII. (Z)-ligustilide, a major constituent in Japanese Angelica Root, for which a method of quantification has not been stipulated in JP XVIII, was also quantitatively analyzed using HPLC and TLC. Furthermore, Japanese Angelica Root was combined with 26 crude drugs to observe the variation in the (Z)-ligustilide content from each combination by TLC. The results revealed that combinations with Phellodendron Bark, Citrus Unshiu Peel, Scutellaria Root, Coptis Rhizome, Gardenia Fruit, and Peony Root increased the (Z)-ligustilide content. Quantifying the constituents in crude drug extracts using the inexpensive and simple TLC method can contribute to elucidating interactions between crude drugs in Kampo medicines, as proposed by the herbal-pair theory.

Efficient fertilization in the cultivation of Angelica acutiloba (Siebold & Zucc.) Kitag. in Hokkaido: Effect of amount of supplied nitrogen on growth, yield, and quality of A. acutiloba

Angelica acutiloba (Siebold & Zucc.) Kitag., the source plant of the crude drug Angelicae acutilobae radix, is traditionally cultivated in western regions of Japan. Since A. acutiloba is now also grown in Hokkaido, the northernmost prefecture of the country, the cultivation method, especially the quantity of fertilizer, needs to be adapted because of the cooler climate and shorter growing period. In this study, we compared plant growth and harvest yield of A. acutiloba cultivated with different amounts of nitrogen (N) fertilizer. When plants were fertilized with 24 kg N/10 a, the aerial part was lush, and the diameter at the top of the root was about 1.3 times thicker than that in plants treated with 12 kg N/10 a. On the other hand, the weight of the harvested root grown with 24 kg N/10 a was slightly, although not significantly, less than that in plants grown with 12 kg N/10 a. In addition, we found that the content of (Z)-ligustilide, a major essential oil contained in A. acutiloba root, is affected by nitrogen application. Interestingly, it increased with increasing amounts of supplied nitrogen. However, the importance of Angelicae acutilobae radix as the crude drug is not limited to its (Z)-ligustilide content, and there are also other crucial quality features, such as having thick lateral roots, which were generated in this study with a moderate nitrogen application. We conclude that about 12 kg N/10 a is the optimal amount of nitrogen for healthy growth of A. acutiloba in Hokkaido.

Studies on cultivation of Angelica acutiloba using paper pot (Part 2): effect of difference in taproot base diameter of seedlings on growth after planting and quality of toki produced from paper pot seedlings

By using Angelica acutiloba seedlings produced by short-period raising in paper pot (PP), we investigated the effect of taproot base diameter on the growth after planting and evaluated the quality of toki (, Angelicae Acutilobae Radix) produced from PP-grown seedlings (PT). In this study, PP-grown seedlings of seven classes which are sorted difference taproot base diameter (P1-P7) were transplanted. As a result, the survival rates were not less than 90% for P6 (taproot base diameter: 10.0-12.7 cm) and P7 (taproot base diameter: 12.8-17.3 cm), and the bolting rates were 20.5% and 24.1% for P6 and P7, respectively. The traditionally grown seedling (TS) showed the highest available harvest rate of 82.3%, followed by P6 (71.8%) and P7 (69.0%). P7 showed the highest fresh weight and dry weight per 1a (100 m²), followed by P6 and TS. However, PP-grown seedlings are prone to bolting, and it is expected the yield can be increased by preventing bolting. In addition, PT satisfied the regulations of JP17 in terms of, for example, dilute ethanol-soluble extract content, total ash content, and acid-insoluble ash content. It was also found that PT has a higher proportion of lateral roots with respect to the total weight than toki produced from traditionally grown seedlings (TT). The total (Z)-ligustilide contents were 0.07% in PT and 0.12% in TT. It was revealed that it is possible to produce toki that satisfies JP17 regulations; moreover, the period required for toki production was shortened by 6 months with PP-grown seedlings.