Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound ...Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound phenolics in three colored quinoas including WQ(white quinoa),RQ(red quinoa)and BQ(black quinoa)were investigated.Result showed a total of 14 phenolics both acted as free and bound form were analyzed in three colored quinoas(WQ,RQ and BQ).Gallic acid,vanillic acid,epicatechin,p-coumaric acid and quercetin existed both as free and bound forms were common phenolics in quinoas.The highest total free phenolics(238.10 mg/kg)and bound phenolics(3377.75 mg/kg)were presented in WQ and RQ,respectively.It indicated WQ and RQ were respectively good source of free and bound phenolics.Moreover,characteristic free and bound phenolics in three colored quinoas could be well analyzed by principal component analysis(PCA),indicating it was an effective and reliable method in distinguishing three colored quinoas based on their characteristic free and bound phenolics,respectively.展开更多
Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free ...Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea.展开更多
Objectives:A comparative study regarding the fatty acid profiles and antioxidant properties of the two most common varieties of rice(Carnaroli and Karnak)cultivated in Sybaris(Southern Italy)was conducted.Carnaroli va...Objectives:A comparative study regarding the fatty acid profiles and antioxidant properties of the two most common varieties of rice(Carnaroli and Karnak)cultivated in Sybaris(Southern Italy)was conducted.Carnaroli variety from Pavia district(Northern Italy)was also investigated.Methods:Free and bound lipids were separately extracted.Fatty acid composition was determined by high resolution gas chromatography(HRGC).Free and bound phenolic acids were determined using high performance liquid chromatography(HPLC).The antioxidant properties were assessed using 2,2’-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging assay.Results:The total lipid content was found to be higher in both Sybaris species with respect to the Pavia variety.The lipid distribution was also significantly different.In particular,the amount of bound lipids(14.2-16.3 mg g−1)was higher than the free lipids(7.2-7.5 mg g−1),and unsaturated fatty acids(USFA)were significantly higher in the free-FA fraction than in bound-FA in both Sybaris varieties.By contrast,Carnaroli variety from Northern Italy displayed a higher content of free(5.3 mg g−1)than bound lipids(2.5 mg g−1)and a higher content of USFA in the bound-FA.The antioxidant activity of Pavia rice extract was higher than that of both Sybaris varieties.Conclusions:The two Sybaris varieties are richer in lipids than the Pavia rice,while exhibiting the same qualitative fatty acid profile with some differences in the content of individual fatty acids.The distribution of lipids(free or bound)was found to be significantly different in the Carnaroli varieties,highlighting the effects of different climatic and pedological areas.展开更多
基金support of Youth Project of Liaoning Provincial Education Department(JYTQN2023334)Anhui Provincial Department of Education Key Research Project on Natural Science in Higher Education Institutions(KJ2021A1072)Science and Technology Plan Project of Chuzhou Science and Technology Bureau(2021ZD023).
文摘Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound phenolics in three colored quinoas including WQ(white quinoa),RQ(red quinoa)and BQ(black quinoa)were investigated.Result showed a total of 14 phenolics both acted as free and bound form were analyzed in three colored quinoas(WQ,RQ and BQ).Gallic acid,vanillic acid,epicatechin,p-coumaric acid and quercetin existed both as free and bound forms were common phenolics in quinoas.The highest total free phenolics(238.10 mg/kg)and bound phenolics(3377.75 mg/kg)were presented in WQ and RQ,respectively.It indicated WQ and RQ were respectively good source of free and bound phenolics.Moreover,characteristic free and bound phenolics in three colored quinoas could be well analyzed by principal component analysis(PCA),indicating it was an effective and reliable method in distinguishing three colored quinoas based on their characteristic free and bound phenolics,respectively.
文摘Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea.
文摘Objectives:A comparative study regarding the fatty acid profiles and antioxidant properties of the two most common varieties of rice(Carnaroli and Karnak)cultivated in Sybaris(Southern Italy)was conducted.Carnaroli variety from Pavia district(Northern Italy)was also investigated.Methods:Free and bound lipids were separately extracted.Fatty acid composition was determined by high resolution gas chromatography(HRGC).Free and bound phenolic acids were determined using high performance liquid chromatography(HPLC).The antioxidant properties were assessed using 2,2’-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging assay.Results:The total lipid content was found to be higher in both Sybaris species with respect to the Pavia variety.The lipid distribution was also significantly different.In particular,the amount of bound lipids(14.2-16.3 mg g−1)was higher than the free lipids(7.2-7.5 mg g−1),and unsaturated fatty acids(USFA)were significantly higher in the free-FA fraction than in bound-FA in both Sybaris varieties.By contrast,Carnaroli variety from Northern Italy displayed a higher content of free(5.3 mg g−1)than bound lipids(2.5 mg g−1)and a higher content of USFA in the bound-FA.The antioxidant activity of Pavia rice extract was higher than that of both Sybaris varieties.Conclusions:The two Sybaris varieties are richer in lipids than the Pavia rice,while exhibiting the same qualitative fatty acid profile with some differences in the content of individual fatty acids.The distribution of lipids(free or bound)was found to be significantly different in the Carnaroli varieties,highlighting the effects of different climatic and pedological areas.
