The medlar security research
|School||Beijing Union Medical College|
|Keywords||Fructus Lycii sulfur dioxide residue tropane-alkaloid safety|
Fructus Lycii is a well-known Chinese herbal medicine, which can be used as both food and medicine in accordance with the report released by Ministry of Health. And it has been widely used as a functional food with a large variety of benefits, such as reducing blood sugar and blood lipid, anti-aging, immunoregulation, anti-cancer, anti-fatigue, and facilitating male fertility. According to the Pharmacopoeia of People’s Republic of China (Vol.1,2010), Fructus Lycii is the dried ripe fruit of Lycium barbarum L while Cortex Lycii Radicis is the dried bark and the root.For the past few years, the export of Fructus Lycii has dramatically and continuously increased along with rising demand, breed improvement and strengthening of production standardization. Meanwhile, Europe and America were constantly raising the standards for Chinese food and agricultural products. Especially since 2007,21 batches of Lycium barbarum L dry fruits and other Lycium barbarum L dry products have been refused entry to United States due to pesticide residues and other safety problems. Therefore, consideration should be given to ways of expanding the Lycium barbarum sales to a larger market. As a result, the safety of Fructus Lycii is our primary concern. Consequently, due to the issues of pesticide residue, sulfur dioxide residue, tropane alkaloids, heavy metal contamination associated with current situation of Fructus Lycii at home and abroad, this research studies the latter three problems in Fructus Lycii to offer guidance for a better understanding of Fructus Lycii safety.The first part of this paper deals with sulfur dioxide residue in Fructus Lycii. According to the Pharmacopoeia of People’s Republic of China, Acid distilled iodine titration was carried out to determine the content of sulfur dioxide in Fructus Lycii from various sources and species. This method is simple and accurate. And the results showed:In 7 samples bought from supermarkets and regular pharmacies in Beijing, sulfur dioxide complied with the standards. But in 4 of 12 samples bought from on-line shops, sulfur dioxide significantly exceeded the limits. And in 3 of 12 samples collected from medicinal markets and habitats, sulfur dioxide went beyond the limit as well. Hence, sulfur fumigation should be our focus.The second part of this paper is about tropane alkaloids in Fructus Lycii. Much of the literature reports that Fructus Lycii contains tropane alkaloids. Harsh, an Indian scholar, addressed that fresh Lycium barbarum L contains atropine and scopolamine in the fruit, the leaf and the extract from tissue culture. Drost-Karbowska K also reported that atropine and scopolamine are present in Lycium halimifolium. Whether Fructus Lycii contains tropane alkaloids is our focus. In the research, LC-MS/MS was employed to detect tropane alkaloids in Fructus Lycii from different sources and species. The results indicated that there was atropine in Fructus Lycii with 3.0 ppb at maximum and scopolamine and anisodamine were not found. The amount of atropine in Fructus Lycii was extremely small and would not affect the human body.The third part of this paper describes heavy metal contamination in Fructus Lycii. At present, metal contamination is serious in many food products. There are two main origins of heavy metal contamination:one is from environmental pollution, including air, water and soil pollution, and the other is from collection, transportation and processing. Heavy metal residues do harm to people’s health. Thus ICP/MS was performed to analyze the heavy metal contamination (Pb, Hg, As, Cd, Cu) in Fructus Lycii. The results showed that Cd and Cu in some examples were out of limit slightly.In conclusion, this research studies the sulphur dioxide residue, tropane-alkaloids and heavy mental residues in Fructus Lycii from various sources and has established sensitive and accurate methods for determination of tropane-alkaloids. The results show that commercial Fructus Lycii is generally safe. But more safety supervision is still needed, together with more reasonable standards.