In this study, accelerated solvent extraction (ASE) was applied to the quantitative extraction of bixin. The effects of cyclohexane/ acetone ratios on bixin extraction yield were evaluated. Acetone was used in the process of pigment extraction and also played a major role in its analysis by UV-Vis spectrophotometry. Pure cis-bixin isolated by flash chromatography and characterized by Fourier Transform Infra Red spectrometry was used as a bixin standard for qualitative and quantitative analysis of annatto extracts which were obtained by accelerated solvents extraction. UV-Vis spectrophotometry analysis shows that the extraction using 100 % cyclohexane gives the lowest bixin yield. This is different from the UV-Vis spectra generated with acetone extraction. The difference in percentage of acetone shows significant effects on bixin extraction yields. The use of cyclohexane: acetone (60 % : 40 %) solution at 50 degrees C for 5 min heating time results the highest total bixin extraction yield (48.00 %) as compared to the other solvent ratios, and to the usual extraction methods using the same solvent (29.14 %). High pressure liquid chromatography analysis shows that bixin extracted by this method has purity degree of 68.16 %

Ziziphus jujuba pulps are very much appreciated by the inhabitants and have been recently exported. This article reports on the chemical composition (amino acids, polyphenols and sugars) of the pulps of four Z. jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The major amino acids identified were proline, aspartic acid and glutamic acid. Among these, proline was the most abundant amino acid (17.4 mol). Considerable differences in total phenolic contents (15.85 mg/L) were found. Predominant phenols identified by using HPLC were rutin (1.09 mg/L) and chlorogenic acid (2.57 mg/100 g). Sugars isolated from Ziziphus pulps were found at a rate of 43.52%. Using HPLC method, three sugars from the pulp extract were identified: glucose, galactose and sucrose. The Mahdia ecotype was the richest in these sugars with 0.45, 136.51 and 113.28 mg/L, respectively.