Simple methods of analyzing proteins and amino acids in small pollen samples

Abstract

For many hymenopteran insects, floral pollen is essential for survival and development. Nutritional analysis of floral pollen is important to understand plant–pollinator interactions. Here, we evaluated a simple method for measuring proteins and amino acids in pollen; it requires samples far smaller than are required by conventional methods. We used a fluorometer for quantitative analysis of protein and investigated its accuracy with small samples (0.01–2.99 mg). Quantitative and qualitative analysis of amino acids was performed by conventional HPLC methods but with smaller samples (0.05–3.0 mg). The two analyses were highly accurate with samples of ≥1.0 mg. Our method allows nutritional analysis of pollen from a wide range of flower species, including those producing only small amounts of pollen, contributing to a better understanding of the interactions between flowers and flower-visiting insects.