Abstract：
A few Capsicum (pepper) species produce yellow-colored floral nectar, but the chemical identity and biological function of the yellow pigment are unknown. A combination of analytical biochemistry techniques was used to identify the pigment that gives Capsicum baccatum and Capsicum pubescens nectars their yellow color. Microbial growth assays, visual modeling, and honey bee preference tests for artificial nectars containing riboflavin were used to assess potential biological roles for the nectar pigment. High concentrations of riboflavin (vitamin B2) give the nectars their intense yellow color. Nectars containing riboflavin generate reactive oxygen species when exposed to light and reduce microbial growth. Visual modeling also indicates that the yellow color is highly conspicuous to bees within the context of the flower. Lastly, field experiments demonstrate that honey bees prefer artificial nectars containing riboflavin. Some Capsicum nectars contain a yellow-colored vitamin that appears to play roles in (1) limiting microbial growth, (2) the visual attraction of bees, and (3) as a reward to nectar-feeding flower visitors (potential pollinators), which is especially interesting since riboflavin is an essential nutrient for brood rearing in insects. These results cumulatively suggest that the riboflavin found in some Capsicum nectars has several functions.
摘要：
一些辣椒（胡椒）物种产生黄色的花蜜，但黄色素的化学身份和生物学功能尚不清楚。使用分析生物化学技术的组合来鉴定赋予辣椒和辣椒蜜汁黄色的色素。微生物生长测定，可视化建模,蜜蜂对含有核黄素的人造花蜜的偏好测试用于评估花蜜色素的潜在生物学作用。高浓度的核黄素（维生素B2）赋予花蜜强烈的黄色。含有核黄素的蜜罐在暴露于光时产生活性氧并减少微生物生长。视觉建模还表明，在花的背景下，黄色对蜜蜂非常明显。最后,田间试验表明，蜜蜂更喜欢含有核黄素的人造蜜腺。一些辣椒蜜汁含有黄色维生素，似乎在（1）限制微生物生长中起作用，(2)蜜蜂的视觉吸引力,和（3）作为奖励花蜜喂养花卉游客（潜在的传粉者），这是特别有趣的，因为核黄素是昆虫育巢的必需营养素。这些结果累积表明，在一些辣椒蜜汁中发现的核黄素具有多种功能。
