Quality analysis of Citri Trifoliatae Fructus in different harvest time by HPLC combined with electronic eye technology / 中国中药杂志

As a local variety of medicinal material, Citri Trifoliatae Fructus is widely used in many places, whereas its harvest time remains unclear. Therefore, studying its harvest time can make more reasonable use of this medicinal material. In this study, we determined the flavonoids content and compared the color of Citri Trifoliatae Fructus harvested in different time, aiming to guide the harvest of this medicinal material. The fresh fruits of Citrus trifoliata were collected from Xinxiang city, Henan province, graded according to the diameter range, and then dried. The contents of isonaringin, naringen, and poncirin in Citri Trifoliatae Fructus were determined by HPLC, and the color values of the samples were detected by electronic eye. The correlation analysis of the obtained data was carried out to explore the relationships of color and diameter with quality. The results showed that the contents of isonaringin, naringen, and poncirin varied significantly in different harvest time, within the ranges of 0.21-1.20, 2.21-11.59, and 3.73-23.16 mg·g~(-1), respectively. With the delay of harvest time, Citri Trifoliatae Fructus showed the color changing from green to yellow, gradually increased diameter, and gradually decreased contents of isonaringin, naringen, and poncirin. The contents of isonaringin, naringen, and poncirin were negatively correlated with the degree of red and green(a~*) and positively correlated with the degree of yellow and blue(b~*). The contents of naringen and poncirin had significantly negative correlations with the diameter. This study indicates that the quality of Citri Trifoliatae Fructus can be judged by its diameter and skin color, which provides a theoretical basis for the rational harvest of this medicinal material.

Extraction, isolation, and identification of a new lectin from Tibetan medicine Auricularia auricula / 中草药

Objective To extract and isolate the lectin from Tibetan medicine Auricularia auricula. Methods The lectin from Tibet A. auricula was separated by sephadex column chromatography and ion exchange chromatography, and then its relative molecular weight was determinated by using matrix assisted laser desorption ionization time of flight mass spectrometry (5 800 MALDI-TOF/TOF). N-terminal sequential detection results suggested the amino acid sequences by comparing with the UniProt database. Results A kind of lectin was obtained from the separation of Tibet A. auricula with the molecular weight of of 18 913.22, in which the N- terminal amino acid sequence was detected as ITAPTTTSSAATE by the full automatic protein polypeptide sequencing instrument. The amino acid sequences of four peptide fragments were QIDAERK, TNHSVVTWNDK, RLNFTAGNPFPR, and VRELEQQVDSMTK. Conclusion These sequences are not found in the existing protein database of A. auricula, indicating that the isolated lectin should be a new type protein and it is confirmed as a new kind of lectin.