123685-24-5Relevant academic research and scientific papers
Enzymatic Synthesis of Bioactive O-Glucuronides Using Plant Glucuronosyltransferases
Yue, Tian,Chen, Ridao,Chen, Dawei,Liu, Jimei,Xie, Kebo,Dai, Jungui
, p. 6275 - 6284 (2019/06/13)
Many O-glucuronides exhibiting various pharmacological activities have been found in nature and in drug metabolism. The glucuronidation of bioactive natural products or drugs to generate glucuronides with better activity and druggability is important in drug discovery and research. In this study, by using two uridine diphosphate (UDP)-dependent glucuronosyltransferases (GATs, UGT88D4 and UGT88D7) from plants, we developed two glucuronidation approaches, pure enzyme catalysis in vitro and recombinant whole-cell catalysis in vivo, to efficiently synthesize bioactive O-glucuronides by the glucuronidation of natural products. In total, 14 O-glucuronides with different structures, including flavonoids, anthraquinones, coumarins, and lignans, were obtained, 7 of which were new compounds. Furthermore, one of the biosynthesized O-glucuronides, kaempferol-7-O-β-d-glucuronide (3a), potently inhibited protein tyrosine phosphatase (PTP) 1B with an IC50 value of 8.02 × 10-6 M. Some of the biosynthesized O-glucuronides also exhibited significant antioxidant activities.
Polyphenols are intensively metabolized in the human gastrointestinal tract after apple juice consumption
Kahle, Kathrin,Huemmer, Wolfgang,Kempf, Michael,Scheppach, Wolfgang,Erk, Thomas,Richling, Elke
experimental part, p. 10605 - 10614 (2009/10/02)
Polyphenols are secondary plant compounds showing anticarcinogenic effects both in vitro and in animal experiments and may thus reduce the risk of colorectal cancer in man. The identification of polyphenol metabolites formed via their passage through the small intestine of healthy ileostomy subjects after apple juice consumption is presented. Identification and quantification of polyphenols and their metabolites were performed using HPLC-DAD as well as HPLC-ESI-MS/MS. Total procyanidin content (TPA) was measured, and additionally the mean degree of polymerization (DPm) of the procyanidins was determined in the apple juice and ileostomy effluents. As products of polyphenol metabolism, D-(-)-quinic acid and methyl esters of caffeic acid and p-coumaric acid are liberated from the corresponding hydroxycinnamic acid esters. 1-Caffeoylquinic acid and 3-caffeoylquinic acid were determined as products of isomerization. Phloretin 2′-O-glucoside (phloridzin) and phloretin 2′-O-xyloglucoside were metabolized into the corresponding aglycons phloretin and phloretin 2′-Oglucuronide and all were found in the ileostomy effluent. Ninety percent of the consumed procyanidins were recovered in the ileostomy effluent and therefore would reach the colon under physiologic circumstances. The DPm was reduced (DPm of apple juice = 5.7) and varied depending on the time point of excretion. The gastrointestinal passage seems to play an important role in the colonic availability of apple polyphenols.
