Lawson L D, Wang Z J
Research Department, Nature's Way Products, Incorporated, Springville, Utah 84663, USA.
J Agric Food Chem. 2001 May;49(5):2592-9. doi: 10.1021/jf001287m.
Most garlic supplements are standardized on allicin potential and are enteric-coated to prevent gastric acid inactivation of the allicin-producing enzyme, alliinase. To determine whether these products release the claimed amount of allicin under simulated gastrointestinal conditions, USP dissolution method 724A for drug release was applied to all 24 known brands of enteric-coated tablets. It was found that nearly all brands employed effective coatings and that they met their claims for allicin potential when crushed and suspended in water. However, all brands except one gave low dissolution allicin release, with 83% of the brands releasing less than 15% of their potential. The low allicin release was found to be due to both impaired alliinase activity, mostly caused by tablet excipients, and to slow tablet disintegration, which also impairs alliinase activity. Only when tablets had high alliinase activity and disintegrated rapidly did they show high allicin release. The ability of USP 724A to estimate allicin release in vivo was validated by monitoring breath levels of the allicin metabolite, allyl methyl sulfide. In conclusion, garlic powder supplements should no longer be standardized on allicin potential, but rather on dissolution allicin release.
大多数大蒜补充剂都以蒜素潜力为标准进行标准化生产，并采用肠溶包衣来防止胃酸使产生蒜素的酶——蒜氨酸酶失活。为了确定这些产品在模拟胃肠道条件下是否能释放出宣称量的蒜素，美国药典（USP）药物释放的溶出度测定方法724A被应用于所有24个已知品牌的肠溶包衣片。结果发现，几乎所有品牌都采用了有效的包衣，并且当它们被碾碎并悬浮于水中时，能达到其宣称的蒜素潜力。然而，除了一个品牌外，所有品牌的蒜素溶出度释放都很低，83%的品牌释放量不到其潜力的15%。发现蒜素释放量低是由于蒜氨酸酶活性受损（主要由片剂辅料引起）以及片剂崩解缓慢（这也会损害蒜氨酸酶活性）。只有当片剂具有高蒜氨酸酶活性且迅速崩解时，它们才会显示出高蒜素释放量。通过监测蒜素代谢物烯丙基甲基硫醚的呼出水平，验证了USP 724A估计体内蒜素释放的能力。总之，大蒜粉补充剂不应再以蒜素潜力为标准进行标准化，而应以溶出蒜素释放量为标准。
