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<i>Brunfelsia calycina</i> flowers lose anthocyanins rapidly and are therefore well suited for the study of anthocyanin degradation mechanisms, which are unclear in planta. Here, we isolated an anthocyanin-&#946;-glycosidase from <i>B. calycina</i> petals. The MS/MS (Mass Spectrometry) peptide sequencing showed that the enzyme (72 kDa) was a &#946;-xylosidase (BcXyl). The enzyme showed high activity to p-Nitrophenyl-&#946;-<span style="font-variant: small-caps;">d</span>-galactopyranoside (pNPGa) and p-Nitrophenyl-&#946;-<span style="font-variant: small-caps;">d</span>-xylopyranoside (pNPX), while no activity to p-Nitrophenyl-&#946;-<span style="font-variant: small-caps;">d</span>-glucopyranoside (pNPG) or p-Nitrophenyl-&#946;-D-mannopyranoside (pNPM) was seen. The optimum temperature of BcXyl was 40 &#176;C and the optimum pH was 5.0. The enzyme was strongly inhibited by 1 mM D-gluconate and Ag⁺. HPLC (High Performance Liquid Chromatography) analysis showed that BcXyl catalyzed the degradation of an anthocyanin component of <i>B. calycina</i>, and the release of xylose and galactose due to hydrolysis of glycosidic bonds by BcXyl was detected by GC (Gas Chromatography) /MS. A full-length mRNA sequence (2358 bp) of <i>BcXyl</i> (NCBI No. MK411219) was obtained and the deduced protein sequence shared conserved domains with two anthocyanin-&#946;-glycosidases (Bgln and BadGluc, characterized in fungi). BcXyl, Bgln and BadGluc belong to AB subfamily of Glycoside hydrolase family 3. Similar to <i>BcPrx01</i>, an anthocyanin-degradation-related <i>Peroxidase</i> (<i>POD</i>), <i>BcXyl</i> was dramatically activated at the stage at which the rapid anthocyanin degradation occurred. Taken together, we suggest that BcXyl may be the first anthocyanin-&#946;-glycosidase identified in higher plants.