Michael C. Tims and Lane C. Sander


Green tea (Camellia sinensis) is a popular botanical supplement reported to contain compounds with anticancer and antimicrobial activities that may also provide cardiovascular protection. Catechins make up 25% (w/w) of green tea leaves, and include cis- and trans-flavan 3 α-ols. Methyl xanthines are also present at high levels, and include caffeine and metabolic precursor theobromine. Like many botanical supplements, validated analytical methods and the reference materials necessary to research supplement label claims are lacking. To address this public need, a collaborative effort was initiated among the National Institute of Standards and Technology (NIST), NIH-ODS, and the Food and Drug Administration (FDA), Center for Food Safety and Applied Nutrition (CFSAN) and Center for Drug Evaluation and Research (CDER) to develop botanical dietary supplement Standard Reference Materials (SRMs). Botanical SRMs are being produced in suites that include dried plant, extract and finished product forms and are primarily intended for use in the development of analytical methods and as control materials to provide the basis for accurate measurement of relevant plant constituents. Several analytical challenges are faced in SRM value assignment. Green Tea SRM development, particularly extraction studies, will be discussed. Our findings will also address how understanding the plant biology of green tea helped get “the numbers” right.



Author information:

Michael C. Tims

Mentor: Lane Sander

Analytical Chemistry Division

Bldg 227 room A119

MS 8392        

x 4026 (ph)

x 0685 (fax)


not a member of Sigma Xi


Poster Category:  Chemistry