TY - JOUR T1 - Isolation and antioxidant activity of zeylaniin A, a new macrocyclic ellagitannin from Syzygium zeylanicum leaves. AU - Nomi,Yuri, AU - Shimizu,Saki, AU - Sone,Yasuko, AU - Tuyet,Mai Truong, AU - Gia,Tien Pham, AU - Kamiyama,Masumi, AU - Shibamoto,Takayuki, AU - Shindo,Kazutoshi, AU - Otsuka,Yuzuru, Y1 - 2012/10/03/ PY - 2012/9/15/entrez PY - 2012/9/15/pubmed PY - 2013/3/27/medline SP - 10263 EP - 9 JF - Journal of agricultural and food chemistry JO - J Agric Food Chem VL - 60 IS - 41 N2 - Methanol extract obtained from Syzygium zeylanicum leaves exhibited potent antioxidant activity. The water extract obtained from this methanol extract by sequential extraction with hexane, chloroform, ethylacetate, and n-butanol also showed the strongest antioxidant activity among extracts. This water extract was further fractionated by column chromatography with various concentrations of methanol solutions. Among the 6 resultant fractions, the fraction developed with 20% methanol exhibited the most potent antioxidant activity. The one peak among the three major HPLC peaks in this fraction was isolated and purified using a preparative HPLC. The structure of a pure compound was elucidated as a novel macrocyclic ellagitannin using a (1)H/(13)C NMR and a high-resolution electrospray ionization mass spectrometer. This newly isolated compound, which was named zeylaniin A, exhibited potent antioxidant activities in the assays of DPPH, oxygen radical absorbance capacity, and malonadehyde/gas chromatography. S. zeylanicum leaves can be a possible source of natural antioxidants. SN - 1520-5118 UR - https://www.unboundmedicine.com/medline/citation/22973981/Isolation_and_antioxidant_activity_of_zeylaniin_A_a_new_macrocyclic_ellagitannin_from_Syzygium_zeylanicum_leaves_ L2 - https://doi.org/10.1021/jf302977n DB - PRIME DP - Unbound Medicine ER -