Development of an Enzyme-Linked Immunosorbent Assay for Specific Detection of Mulberroside A in Mulberry (Morus alba L.) Using Anti-mulberroside A Polyclonal Antibody

An enzyme-linked immunosorbent assay (ELISA) was developed using polyclonal antibody (PAb) against mulberroside A (MuA), a major active component found in the root bark of mulberry (Morus alba L.). MuA was conjugated with the carrier protein bovine serum albumin for immunization to rabbits. The results showed that the antibodies were specific only for MuA and have very low specificity for its aglycone, oxyresveratrol. The ELISA assay was suitable for quantitating MuA in the range of 0.17–15.62 μg/mL with a relative standard deviation (RSD) of less than 5 % for both intra- and inter-assay precision levels. The recovery rates of MuA in the samples were in the range of 97.6–101.4 % with a RSD of less than 5 %. The developed ELISA exhibited a good correlation value (R ²?=?0.994) with the standard high-performance liquid chromatography method in the crude extracts of plant samples. These results suggest that the developed ELISA method using PAb against MuA can be applied to determine MuA content with high specificity, rapidity, and simplicity in mulberry samples. The developed ELISA method described could prove to be useful as an analytical tool for quality control of mulberry and their products.     

Development of Anti-Asiaticoside Polyclonal Antibody-Based Immunoassay and Applications for Centella asiatica Products and Human Serum

A sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed using polyclonal antibody (PAb) against asiaticoside (AS), one of the triterpenoid saponins found in Centella asiatica (Linn). AS-bovine serum albumin conjugate was immunized to rabbits for producing PAb. The results showed that the antibodies were specific only for AS and very low specific for madecassoside whose basic skeleton is almost the same as AS. The range of the assay extends from 0.05?C25 ??g/ml of AS. A good correlation between ELISA and high-performance liquid chromatography methods was obtained when analysis of AS in the crude extracts of plant samples. In addition, the products containing C. asiatica in various preparations were determined AS content by competitive ELISA. The results showed that the product from tea bag preparation gave the highest yield of AS content (35.59?mg/g dry wt) comparing to other preparations. In order to evaluate the matrix effect of the serum for AS immunoassay, the standard curves of AS in different media were observed. Standard curve of the serum was similar to the water media and both curves showed the measurement range of 0.20?C6.25???g/ml. The developed ELISA method can be used for quality assessment of C. asiatica and their products including AS detection in serum samples.