The interaction between biomacromolecules and ligands has attracted great interest because of their biological properties. Calf thymus DNA (ctDNA) can interact with bioactive compounds to form complexes. Here, ctDNA-ligand complexes were studied using fluorescence, absorption, and infrared spectroscopy, circular dichroism, ABTS assay and competitive displacement. The binding constants of bioactive compounds at the intercalative site of ctDNA ranked in order kaempferol > apigenin > quercetin > curcumin > riboflavin, while the binding constants at minor groove sites ranked quercetin > kaempferol > naringenin ~ apigenin > hesperetin > curcumin ~ resveratrol ~ riboflavin > caffeic acid. CtDNA maintained stable B-form with an enhancement of base stacking and a decrease of right-handed helicity in the presence of these bioactive compounds, except for hesperetin and caffeic acid. Bioactive compounds preferentially bound to guanine bases and tended to transfer into a more hydrophobic environment upon complexation with ctDNA. The DNA complexation did not affect the ABTS·⁺ scavenging capacity of quercetin, kaempferol, resveratrol and apigenin but increased the ones of naringenin, caffeic acid, curcumin, hesperetin and riboflavin. The data gathered here should be useful to understand the binding modes of DNA with ligands for their potential application in pharmaceutical and food industries.

生物大分子与配体之间的相互作用由于其生物学特性而引起了极大的兴趣。小牛胸腺DNA（ctDNA）可以与生物活性化合物相互作用形成复合物。在这里，使用荧光，吸收和红外光谱，圆二色性，ABTS分析和竞争置换研究了ctDNA-配体复合物。生物活性化合物在ctDNA插入位点的结合常数按山ka酚>芹菜素>槲皮素>姜黄素>核黄素的顺序排列，而在小沟部位的结合常数按槲皮素>山ka酚>柚皮素〜芹菜素>橙皮素>姜黄素〜白藜芦醇〜核黄素咖啡酸。在含有这些生物活性化合物的情况下，除橙皮素和咖啡酸外，CtDNA保持稳定的B型，增加了碱基堆积，并减少了右旋螺旋度。生物活性化合物优先结合鸟嘌呤碱基，并在与ctDNA络合后倾向于转移到疏水性更高的环境中。DNA络合不影响ABTS·⁺槲皮素，山emp酚，白藜芦醇和芹菜素的清除能力，但增加了柚皮素，咖啡酸，姜黄素，橙皮素和核黄素的清除能力。此处收集的数据应有助于理解DNA与配体的结合模式，以将其潜在地应用于制药和食品行业。