CAJ | 학술논문

运用荧光光谱、红外光谱、圆二色谱和拉曼光谱等四种光谱手段，研究了鱼胶原蛋白肽（FC P ）与表没食子儿茶素没食子酸酯（EGCG）在水溶液中的相互作用。荧光结果表明：EGCG使 FCP中的酪氨酸荧光强度减小，促进了二酪氨酸的形成；FCP与EGCG能够形成 FCP-EGCG非共价复合物，同时，EGCG影响了FCP中酪氨酸的微环境。红外光谱分析表明：FCP具有胶原蛋白特征吸收带；EGCG 的加入使3281 cm －1处的吸收峰消失，3076 cm－1处的吸收峰红移，表明EGCG影响了酰胺A带和酰胺B带；1659和1689 cm －1处的吸收峰蓝移，1547 cm －1处的吸收峰红移以及1248 cm －1处吸收峰的消失，表明FC P中酰胺Ⅰ带、酰胺Ⅱ带和酰胺Ⅲ带均受到EGCG的影响。圆二色谱分析表明：添加 EGCG后，FCP 222 nm处的负峰消失，198 nm处的负峰依次红移至200和204 nm ，说明EGCG影响了FCP的二级结构。拉曼光谱分析结果表明：EGCG的加入影响了FCP中酰胺Ⅰ带、酰胺Ⅱ带和酰胺Ⅲ带的吸收；同时，EGCG的添加使863和932 cm －1处的峰红移，前者峰强度降低，后者峰强度大幅增加，表明羟脯氨酸和脯氨酸均参与了与 EGCG的结合，且EGCG浓度的增加使更多的脯氨酸暴漏。
운용형광광보、홍외광보、원이색보화랍만광보등사충광보수단，연구료어효원단백태（FC P ）여표몰식자인다소몰식자산지（EGCG）재수용액중적상호작용。형광결과표명：EGCG사 FCP중적락안산형광강도감소，촉진료이락안산적형성；FCP여EGCG능구형성 FCP-EGCG비공개복합물，동시，EGCG영향료FCP중락안산적미배경。홍외광보분석표명：FCP구유효원단백특정흡수대；EGCG 적가입사3281 cm －1처적흡수봉소실，3076 cm－1처적흡수봉홍이，표명EGCG영향료선알A대화선알B대；1659화1689 cm －1처적흡수봉람이，1547 cm －1처적흡수봉홍이이급1248 cm －1처흡수봉적소실，표명FC P중선알Ⅰ대、선알Ⅱ대화선알Ⅲ대균수도EGCG적영향。원이색보분석표명：첨가 EGCG후，FCP 222 nm처적부봉소실，198 nm처적부봉의차홍이지200화204 nm ，설명EGCG영향료FCP적이급결구。랍만광보분석결과표명：EGCG적가입영향료FCP중선알Ⅰ대、선알Ⅱ대화선알Ⅲ대적흡수；동시，EGCG적첨가사863화932 cm －1처적봉홍이，전자봉강도강저，후자봉강도대폭증가，표명간포안산화포안산균삼여료여 EGCG적결합，차EGCG농도적증가사경다적포안산폭루。
Fish collagen is known to have good moisturising property and antioxidant ability ,which has been increasingly added into cosmetics ,foods and drinks as thicker agent and to increase dietary supply of collagen .Fish collagen peptide (FCP) is a white or pale yellow powder ,obtained by extracting collagen from sources including the scales and bones of fish such as bonito , halibut ,tuna ,and sea bream .It is identical to human collagen and 100% absorbable through the skin .(-)-Epigallocatechin-3-gallate (EGCG) ,the major constituent of green tea ,has lots of beneficial biological and pharmacological effects ,including an-tioxidant ,antimutagenic ,antiviral and antiinflammatory activities .Because proteins have the desirable formulation of EGCG-for-tified food ,the interaction between proteins and EGCG molecules has been widely studied .At the same time ,the interaction of proteins and EGCG was known to affect the content of free EGCG ,structure of proteins ,antioxidant capacity of EGCG in foods . But ,to our knowledge ,the interaction between FCP and EGCG has not been characterised clearly ,and little is known about their interaction mechanism .Therefore ,a better understanding of the interaction between FCP and EGCG would help to control their functional properties in food products during processing ,transportation and storage when we facilitate FCP as the vehicles for EGCG .In view of the above ,we planned to study the interaction of FCP with EGCG by using different spectroscopic tech-niques ,such as fluorescence spectroscopic ,FTIR ,CD and Raman .EGCG caused a concentration dependent quenching of the in-trinsic fluorescence of tyrosine residue in the FCP ,indicating the occurrence of interactions between FCP and EGCG .Excimer-like species and dityrosine were regularly formed with the addition of EGCG into the solution ,and the interaction of FCP and EGCG partly disrupted the structure of the protein .Synchronous fluorescence results indicate that the interaction caused de-crease of the polarity around tyrosine residues resulting in FCP conformation alteration .FTIR showed that the frequency of 3 281 and 1 248 cm -1 declined ,the absorption peaks at 3 076 and 1 547 cm -1 had a slight red-shift ,the absorption peaks at 1 659 and 1 689 cm-1 had a slight blue-shift in the FCP-EGCG complexes .It is interesting to observe that the CD intensity of FCP around 198 nm decreased with high EGCG concentration ,and the peak maximum shifted to a larger wavelength (red shift ) .Raman spectra showed that peaks at 863 and 932 cm -1 had a slight red-shift ,and decreased intensities near 932 cm -1 suggested that more exposure of proline when FCP-EGCG complexes formed .This study provides a theoretical basis for fortifying FCP prod-ucts with EGCG .