Bennick Anders
Department of Biochemistry and Faculty of Dentistry, University of Toronto, 1 King's College Circle, Toronto M5S 1A8, Ontario, Canada.
Crit Rev Oral Biol Med. 2002;13(2):184-96. doi: 10.1177/154411130201300208.
Tannins are polyphenols that occur widespread in plant-based food. They are considered to be part of the plant defense system against environmental stressors. Tannins have a number of effects on animals, including growth-rate depression and inhibition of digestive enzymes. Tannins also have an effect on humans: They are, for example, the cause of byssinosis, a condition that is due to exposure to airborne tannin. Their biological effect is related to the great efficiency by which tannins precipitate proteins, an interaction that occurs by hydrophobic forces and hydrogen bonding. Two groups of salivary proteins, proline-rich proteins and histatins, are highly effective precipitators of tannin, and there is evidence that at least proline-rich proteins act as a first line of defense against tannins, perhaps by precipitating tannins in food and preventing their absorption from the alimentary canal. Proline plays an important role in the interaction of proline-rich proteins with tannins. In contrast, it is primarily basic residues that are responsible for the binding of histatins to tannin. The high concentration of tannin-binding proteins in human saliva may be related to the fruit and vegetable diet of human ancestors.
单宁是广泛存在于植物性食物中的多酚类物质。它们被认为是植物抵御环境应激源防御系统的一部分。单宁对动物有多种影响，包括生长速率降低和消化酶抑制。单宁对人类也有影响：例如，它们是棉尘病的病因，棉尘病是由于接触空气中的单宁所致。它们的生物学效应与单宁沉淀蛋白质的高效性有关，这种相互作用是通过疏水作用力和氢键发生的。两组唾液蛋白，富含脯氨酸的蛋白质和富组蛋白，是单宁的高效沉淀剂，并且有证据表明至少富含脯氨酸的蛋白质作为抵御单宁的第一道防线，可能是通过沉淀食物中的单宁并阻止其从消化道吸收。脯氨酸在富含脯氨酸的蛋白质与单宁的相互作用中起重要作用。相比之下，主要是碱性残基负责富组蛋白与单宁的结合。人类唾液中单宁结合蛋白的高浓度可能与人类祖先的水果和蔬菜饮食有关。
