Studies On The Analytic Method For Non-anthocyanin Phenolic Compounds In Raspberry Fruits

Non-anthocyanin phenol is a secondary metabolite in raspberry fruits,which has various health functions such as reducing blood sugar,anti-inflammatory,sterilization,preventing cancer and cardiovascular disease.This study used the raspberry fruits(‘Autumn Bliss’)as the experimental material,which were collected at the horticultural experiment station of Northeast Agricultural University.And the optimal conditions were established to detect the non-anthocyanin phenol in raspberry fruits by UHPLC-MS/MS in order to provide atechnical support and theoretical basis for exploiting and utilizing the non-anthocyanin phenol in raspberry fruits.The results are showed as follows:(1)This experiment take the content of total phenol extracted as an indicator,and investigate five factors including methanol concentration,solid-liquid ratio,extraction temperature,extraction time and extraction times,which affects the total phenol extraction quantity,then orthogonal test were employed to optimize the extraction conditions.As a result,the optimum extraction technology for total phenol extraction in raspberry fruits was obtained as follows: methanol concentration 70%,solid-liquid ratio 1:70(g/m L),extraction temperature 40°C,extraction time 1.5 h,extraction times 3 times.(2)The optimum conditions were established for the determining the non-anthocyanin phenols in raspberry fruits by UHPLC-MS/MS.The Chromatographic detection condition: ACQUITY UHPLC BEH C18 chromatographic column(100 mm×2.1 mm,1.7 μm);The mobile phase A was ultrapure water containing 0.1% formic acid,and mobile phase B was pure acetonitrile;Column temperature was 25°C;Sample volume was 5 μL;The flow rate was 0.4 m L/min;Detection wavelength was 280 nm;Detection time was 25 min.Gradient elution conditions:0-3 min,5%-15% B;3-3.5 min,15% B;3.5-6 min,15%-30% B;6-6.5 min,30% B;6.5-12 min,30%-70% B;12-12.5 min,70% B;12.5-18 min,70%-95% B;18-22 min,95% B;22-22.5 min,95%-5% B;22.5-25 min,5% B.The Mass spectrum detection condition: Negative ion scanning pattern;The scanning range of ESI-MS was 100-1200 m/z;Nebulizer gas was 55 psi;Source gas 2 was 55 psi;Curtain gas was 35 psi;Temperature was 500°C;Ionspray voltage floating was-4500 V;Collision energy was-10 V;Declustering potential was-100.0 V.The scanning range of ESI-MS2 was 50-1000 m/z;Nebulizer gas was 55 psi;Source gas 2 was 55 psi;Curtain gas was 35 psi;Temperature was 500°C;Ionspray voltage floating was-4500 V;Declustering potential was-100 V;Collision energy was-40 V;Collision energy spread was 20 V.(3)There are five kinds of non-anthocyanin phenolic compounds were detected in raspberry fruits(‘Autumn Bliss’),including caffeic acid,catechin,vanillic acid,ellagic acid and quercetin.Quantitative analysis showed that the content of ellagic acid was 116.98 μg/g,which was the highest among the five kinds of non-anthocyanin phenolic compounds,secondly were catechin and quercetin,there were 106.59 μg/g and 35.73 μg/g respectively.The contents of vanillic acid and caffeic acid were lower,there were 14.63 μg/g and 4.17 μg/g respectively.