Arch. Pharm. Res. Vol.21, No.5, pp. 514-520, 1998 The Developement of a New Method to Detect the Adulteration of Commercial Aloe Gel Powders Kyeong Ho Kim 1, Jin Gyun Lee 1, Do Gyuun Kim 1, Min Ki Kim 1, Jeong Hill Park z, Yong Geun Shin 2, Seung Ki Lee2, Tae Hyung Jo 3 and Sun Tack Oh 3 1College of Pharmacy, Kangwon National University, Chunchon 200-701, Korea, 2College of Pharmacy, Seoul Na- tional University, Seoul 151-742, Korea and 3Namyang Aloe Co., Jincheon 365-850, Korea (Received February 26, 1998) Simple and accurate methods to detect the adulteration of commercial aloe gel powder were developed. Crude polysaccharide in aloe gel powder was isolated by precipitating with excess ethyl alcohol and total hexose in isolated polysaccharide was determineded by Dubois assay. After hydrolysis of non-dialysable polysaccharides, resultant free sugar was determined by gas chromatography for sugar recognition and ash contents was considered simultaneously. In some products, the content of ash was very low while the content of total hexose was very high. And polysaccharides of these products revealed typical dextran pattern, therefore, these products could be identified that adulterated with commercial maltodextrin. The content of maltodextrin in adulterated product was determined by HPLC and TLC analysis which could be adopted as a part of a certification process. Key words : Aloe gel powder, Adulteration, Maltodextrin INTRODUCTION Aloe has long been used in folk medicine for the treatment of diarrhea, burns and dermatitis. Generally, several anthraquinones, anthrones, chromones and their C-glycosyl derivatives was known to have various biological activities, such as wound-healing effect, anti- inflammatory effect, antibacterial and immuno-mo- dulating effect, antigastric ulcer effect, hypoglycemic and antidiabetic effect and so on (Heggers et aL, 1995; Hikino et al., 1986; Hirata eta/., 1978; Obata et al., 1993; Saito et al., 1989; Yamamoto eta/., 1991). Therefore, in recent years considerable attention has been directed to the use of aloe species as healthy foods and new drugs and sales of products derived from aloe species are growing rapidly. Large numbers of aloe products are commercial in various fields of industry, and therefore many kinds of aloe gel powders are merchandised. But as in all food industries, where opportunities exist to realize large margins, unscrupulous people will exploit the situation. For protecting the image of Aloe as a safe and pure product, quality control of aloe products is necessary. After L-malic acid was proposed as a marker of aloe products (Pelley eta/., 1992; Pelley eta/., 1993), artificial addition of synthetic D-malic acid to the Correspondence to: Kyeong Ho Kim, College of Pharmacy, Kangwon National University, Chunchon 200-701, Korea adulterated aloe products could be found out, but it was impossible to find out the adulteration if L-malic acid was added. We tried the quality control with phenolic compounds in aloe species such as aloesin, methylaloesol, aloeresinD, barbaloin and aloe-emodin etc., but failed because the contents of them were varied significantly according to the processes of maufacturing. In order to detect the adulteration of aloe product with polysaccharide, many researchers have developed various methods. Carbohydrate pattern in aloe plant was studied (Mandel et a/., 1980a, Mandel eta/., 1980b). Polysaccharides were isolated by alcohol precipitation method and determined by the phenol-sulfuric acid colorimetric method (Hodge et aL, 1962; Whistler et a/., 1962). The isolated crude polysaccharids were purified by dialysis across a membrane with a cut- off approximately 5,000 MW for removal of small molecular interfering substances. They were hydrolyzed and the resultant free sugars were determined (Gowda et aL, 1979; Waller et al., 1994). But the analysis of polysaccharide in aloe products cannot reveal the adulteration completely. We have tried many methods and found that com- mercial aloe products were adulterated with maltod- extrin. The qualitative TLC method and quantitative HPLC method were developed for the tranditional polysaccharide analysis. 514