Pueraria candollei var. mirifica (herein after “Pueraria mirifica” or “P. mirifica”) is a member of the family Leguminosaea, sub-family Papilionoideae, belonging to the soybean and pea sub-family of plants. The Pueraria species are strong climbers, creeping in and over low vegetation or climbing high in tall trees. More than 100 different sub-species of Pueraria have been taxonomically identified world-wide, many of which are found in Asia, Australia, Africa and North, Central and South America.

        Pueraria mirifica root is a popular traditional medicine of Thailand known locally as “white Kwaw Krua” or by its other common Thai name, “Kwao keur.” It is found within the boundaries of Thailand in mixed forest areas located in the north, west and northeast parts of the country, at elevations between 300 and 800 meters. Plants harvested for extraction are generally 2-4 years old; older plants having a lower yield per kilo of the desired active compounds. It takes highly skilled harvesters to be able to correctly select P. mirifica roots and not other subspecies’ roots, such as P. Pueraria candollei. Obtaining the proper sub-species from sources in Thailand that are able to obtain only genuine P. mirifica root, and not other Pueraria sub-species, is extremely important in insuring that a therapeutic product is used in manufacturing, to avoid mislabeling or false labeling, as there are 13 species of the Pueraria genus growing in Thailand:

        Confusion about which species to harvest is an outgrowth of local Thai languages. This arose when Thai people linguistically generalized two different species of Pueraria by using a similar Thai word, “Kwao Krua.” Unless care is taken by harvesters, the distinction between several of the Pueraria sub-species is difficult to make for 50 weeks of the year, as there is remarkable similarity in the appearance of the flowers and leaves between each subspecies. Superficial observation cannot adequately distinguish the differences, even for local natives. Two subspecies that are very similar in appearance are P. mirifica and Pueraria candollei.


        The Thai Ministry of Public Health, which includes the Thai Food and Drug Administration (FDA) is very well aware of this situation, and taking progressive steps to correct the situation, especially related to exported product.