ABSTRACT
The spectrophotometric method was established for the determination of total tannin content in gardenia medicinal materials and tannins, and HPLC method was applied to simultaneously determine gallic acid, punical glucoside A, methyl gallate, punny glucoside B, corilagin, pentagalloyl glucose and the content of ellagic acid. Taking gallic acid as a reference substance, a phosphomolybdate tungstic acid colorimetric method (Pharmacopoeia method) was used to determine the total tannin content. With the chromatographic column Agilent ZORBAX SB-Aq-C18 (250 × 4.6 mm, 5 microns), mobile phase for phosphoric acid (0.1％), methanol, water flow rate of 1 ml/min, column temperature 30℃, detection wavelength of 270 nm, gradient elution, 7 kinds of component contents in myrobalan medicinal materials were measured at the same time. The result showed that the average content of total tannins of Radix Scutellariae was 30.31％, RSD was 0.55％; the average recovery rate was 99.70％, and the RSD was 21.97％ (n = 6) . In the scorpion medicinal materials, gallic acid, punical glucoside A, punny glucoside B, methyl gallate, punny glucoside B, creatin, pentagalloglucose and ellagic acid have a good linear relationship in their respective ranges. The recovery rate of the sample is between100.10％ and 102.77％. The establishment of the determination method of total tannin, gallic acid, punical glucoside, methyl gallate, corridain, pentagalloglucose and ellagic acid in the scorpion medicinal materials is simple and accurate, which has strong specificity and can be used for quality control of Terminalia chebular.
ABSTRACT
Objective: To investigate the antioxidant activity, total phenolic and total tannin content of the pericarp and the seed of Coffea benghalensis (C. benghalensis) and Coffea liberica compared to Coffea arabica (C. arabica). Methods: The antioxidant potential, total tannin and polyphenol contents of the immature and mature seed and pericarp of C. benghalensis and Coffea liberica were quantified and compared to C. arabica. Enhanced chemiluminescence (ECL), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, Folin-Ciocalteau method and total tannin content assays were used. Results: Trolox equivalent (TE/g plant material) values obtained by ECL and DPPH methods showed loose correlation (r
ABSTRACT
OBJECTIVE@#To investigate the antioxidant activity, total phenolic and total tannin content of the pericarp and the seed of Coffea benghalensis (C. benghalensis) and Coffea liberica compared to Coffea arabica (C. arabica).@*METHODS@#The antioxidant potential, total tannin and polyphenol contents of the immature and mature seed and pericarp of C. benghalensis and Coffea liberica were quantified and compared to C. arabica. Enhanced chemiluminescence (ECL), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, Folin-Ciocalteau method and total tannin content assays were used.@*RESULTS@#Trolox equivalent (TE/g plant material) values obtained by ECL and DPPH methods showed loose correlation (r(2) = 0.587) while those measured by oxygen radical absorbance capacity assay were higher without correlation in each plant. A closer correlation was detected between the ECL method and the percentage antioxidant activity of the DPPH technique (r(2) = 0.610 7) in each species, however the immature pericarp of C. benghalensis showed much higher DPPH scavenging potential than was seen in the ECL assay. The immature pericarp of C. benghalensis expressed the highest tannin and polyphenol content, and a high polyphenol level was also detected in the immature seed of C. arabica. The immature pericarp of Bengal and Liberian coffees showed the largest amount of phenolic contents.@*CONCLUSIONS@#The obtained data highlight the potential role of C. benghalensis as a new source of natural antioxidants and polyphenols compared to C. arabica.