Screening of Centella asiatica drying method based on comprehensive evaluation of quality / 中草药

ABSTRACT

Objective: To explore the effects of different drying methods on the quality of medicinal materials, and screen out the optimal drying process of Centella asiatica. Methods: The whole fresh grass of C. asiatica were dried by hot air, drying in the sun, drying in the sun and hot air combined, drying in the shade, microwave and vacuum respectively. Meanwhile, the drying time and rate were determined. The characters, identification, inspection, and leachable content of C. asiatica were analyzed by the method of pharmacopoeia. The content of asiaticoside, madecassoside, asiatic acid, madecassic acid, kaempferol-3-O-tutinoside, kaempferol, and quercetin were detected by HPLC analysis; The weighted scoring method was used to sort the comprehensive evaluation of multiple indexes. Results: Different drying methods consume different time, among which drying in the sun, shade and drying at 50 ℃ for more than 100 h, and the average drying rate was 24.83%. The effects of different drying methods on the properties of medicinal materials are mainly reflected in color and odor, among which 50-70 ℃ hot air drying had a better color, which was light green, and the odor of hot air drying and microwave drying at 80 ℃ and 85 ℃ also changed significantly. Although there were some differences in moisture and ash content, both of them met the pharmacopoeia standards. The drying method also had certain effects on the leachable, the maximum was 45.70%, and the minimum content of dry extract was 29.67%. The highest content of the total active ingredient was determined by HPLC using the method of drying in the shade, which was 83.032 mg/g, and the lowest was is 75 ℃ hot air drying, which was 40.982 mg/g. The highest total content of madecassoside and asiaticoside was 80 ℃ hot air drying, and the lowest was 75 ℃ hot air drying. Weighted score in the top three of line was 70 ℃, dried at 50 ℃ after drying in the sun, hot air drying at 50 ℃, and 85 ℃ hot air drying ranked the bottom. Conclusion: In summary, the suitable drying method for the production area of C. asiatica was 70 ℃ hot air drying.