SUPPLEMENTARY MATERIAL

Transcription

1 SUPPLEMENTARY MATERIAL Artepillin C, is it a good marker for quality control of Brazilian Green Propolis? Cui-ping Zhang 1, Xiao-ge Shen 1, Jia-wei Chen 1, Xia-sen Jiang 1, Kai Wang 2, Fu-liang Hu 1 * 1. College of Animal Sciences, Zhejiang University, No.866 Yuhangtang Road, Hangzhou , China 2. Institute of Apicultural Research, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China Abstract: As commercialization of Brazilian green propolis is going on, quality evaluation and authenticity are important. The result demonstrated that artepillin C only found by far in Brazilian green propolis by HPLC-ESI-MS/MS analysis, while a small interferent may be mistaken as artepillin C in some propolis from China. A new HPLC quality control method as artepillin C for marker was developed, which is the primary assessment criteria for quality control of Brazilian green propolis. Key words: HPLC; Brazilian green propolis; Artepillin C; Quality control

2 Experimental Chemicals and reagents HPLC-grade methanol was obtained from Merck (Darmstadt, Germany). HPLC-grade water was obtained from Yjd-upws ultra-pure water system (Hangzhou, China). Absolute alcohol and acetic acid were analytical grade. Artepillin C (purity 98%) was purchased from Wako (Japan). Propolis samples Brazilian green propolis samples were supplied by Fengnaibao Benpu(Nanjing) Health-care Food Co., Ltd and Hangzhou Bee Words Bee Industry Stock Corp. LTD. In total 35 Chinese propolis samples were harvested by local beekeepers in 20 provinces from China (Fig.S1). Birch-type propolis, Ecalyptus-type and Macaranga-type propolis samples were supplied by the China Bee Products Association (Beijing, China). These samples were frozen at -20 until analysis. Sample preparation Raw samples (0.25g) of different types were first ground, homogenized, then mixed with 85% ethanol (1:15)and agitated in an ultrasonic water bath for 15min. The resulting mixture was filtered and the residue was re-extracted twice under the same conditions. After the 3rd extraction, the filtered solution was combined and transferred into a volumetric flask and then adjusted to 50 ml, filtered through a 0.45 μm membrane filters before injection. The peak was assigned by comparing its retention time with that of artepillin C. The content of artepillin C was determined from the corresponding calibration curve. HPLC-MS/MS The chromatographic system consisted of an Agilent Technologies 6460, equipped with a quaternary pump G4220A, an auto-samplerg4226a, a VWD G1314E, and a Thermostatted Column Compartment G1316C (Agilent Technologies, Inc., Santa Clara, Calif., U.S.A.). A SepaxHP-C18 column (150 mm 4.6 mm, 5 μm)was applied for all analyses. The column was maintained at 30 ; The separation was performed by means of a linear gradient elution (elute A, 1.0% aqueous acetic acid

3 (v/v); elute B, methanol). The gradient was as follows: 25% to 55% (B) at0 to 30 min, 55% to 80% (B) at 30 to 60 min, 80% to 95% (B)at 60 to 70 min,95% to 25% (B) at 70 to 80 min at a flow rate of 1.0mL/min. The effluent was monitored at 310 nm. The injection volume was 2 μl. Electrospray ion source (ESI)-MS 2 spectra were acquired in both positive and negative ion modes, and the interface and MS detector parameters were as follows: the capillary voltages were4 KV and 3.5 KV for positive and negative ion modes, respectively, and nitrogen was used as the nebulising gas. The desolvation temperatures were set at 350 C. and the drying gas flow andtemperaturewere5.0 L/min and 350, sheath gas temperature, 350 C;sheathgasflow, 11 L/min; nebuliser gas, 45.0 psig. For full scan MS analysis, the spectra were recorded in the range of m/z HPLC procedure The chromatographic system system consisted of an Agilent 1200 series, equipped with a vacuum degasser G 1322A, a quaternary pump G1311A, an auto-samplerg1329a, a programmable variable wavelength detectorg1314b, and a Thermostatted Column Compartment G1316A (Agilent Technologies, Inc., Santa Clara, Calif., U.S.A.). The HPLC analysis conditions are same as HPLC-MS/MS..

4 Table S1: Artepillin C content (%) in different batches of Brazilian green propolis Samples Content(%) Samples Content(%) Samples Content(%) Samples Content(%)

5 Figure S1Distribution of sampling locations. The numbers in parentheses indicate the sample size of each province.

6 mau A B C D E F min Figure S2 HPLC chromatogram of artepillin C and the other 4 different types of propolis: A, Standard solution of artepillin C(0.3mg/mL); B, Brazilian green propolis; C, Macaranga-type propolis;d, Eucalyptus-type propolis; E, Birch-type propolis; F, Poplar-type propolis.

7 Fig S3a Negativie and positive ion MS 2 spectra of artepillin C Fig S3b Negativie and positive ion MS 2 spectra of artepillin C in Brazilian green propolis Fig S3c Negativie and positive ion MS 2 spectra of unknown peak in Chinese propolis FigureS3 Artepillin C in Chinese and Brazilian green propolis by MS/MS

8 a b c a b c FigureS4 Artepillin C in Brazilian green propolis and Chinese by HPLC-ESI/MS a: artepillin C; b: Brazilian green propolis; c: Chinese propolis