Qualities of Whitmania pigra in different-month-age and best harvest time
Quality control study published in China Journal of Chinese Materia Medica (2009)
Abstract
OBJECTIVE: Dynamic changes of quality and growth of Whitmania pigra were investigated to provide theoretical basis for quality control and determination of optimal harvest time. METHOD: The contents of moisture, ethanol-soluble extractive, total ash, and acid-insoluble ash, as well as antithrombin activity were determined according to Chinese pharmacopoeia (2005 edition). RESULT: Qualities of W. pigra collected from different growth stages met the standards of Chinese pharmacopoeia (2005 edition). The highest amount of ethanol-soluble extract was found in 9-month-old, W. pigra, followed by 6-month-aged ones. And there was significant difference between 9-month-old and 4-month-old, 7 month-old and 11 month-old (P < 0.05). The highest antithrombin activity was detected in 6 month-old W. pigra, followed by 10 month-old. Significant differences of antithrombin activity were found between 6-month-old and 4 month-old ones, and 5 month-old (P < 0.05), however, there were no significant difference between 6 month-old ones with other samples. Eleven-month-old W. pigra got the most dry weight, and there were significant difference between 11 month-old ones with other samples (P < 0.05). CONCLUSION: November, namely for 6 month old artificial cultivated W. pigra was the best harvest time in Jiangsu and Zhejiang provinces.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Dynamic monthly quality assessment of cultivated Whitmania pigra leech in Jiangsu/Zhejiang provinces: 6-month-old leeches showed highest antithrombin activity, supporting November harvest for optimal therapeutic potency.
Why This Matters for Hirudotherapy
This comparative study investigated dynamic changes in quality and growth of Whitmania pigra—a leech species used in traditional Chinese medicine—across different month-ages (4 through 11 months), measuring moisture, ethanol-soluble extractive, total ash, acid-insoluble ash, and antithrombin activity per Chinese Pharmacopoeia (2005 edition) standards. The highest antithrombin activity was found in 6-month-old specimens, while the highest ethanol-soluble extract content occurred at 9 months, and the greatest dry weight at 11 months. The authors conclude that November—corresponding to 6-month-old artificially cultivated W. pigra—represents the optimal harvest time in Jiangsu and Zhejiang provinces. For ASH, this study offers relevant data on how antithrombin activity in medicinally used leeches varies with developmental stage, informing quality control considerations. However, W. pigra is a species used in Chinese traditional medicine rather than the Hirudo species standard in Western hirudotherapy, limiting direct applicability.
Citation
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