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ARS Home » Pacific West Area » Tucson, Arizona » Carl Hayden Bee Research Center » Research » Research Project #442675

Research Project: Nutritional Analysis of Pollen from Bee Pollinated Plants

Location: Carl Hayden Bee Research Center

Project Number: 2022-21000-022-053-I
Project Type: Interagency Reimbursable Agreement

Start Date: Jul 15, 2022
End Date: Sep 30, 2023

1) To quantify concentrations of protein, lipid, amino and fatty acids in pollen from plants that are foraged by bees. 2) To provide the information to collaborators and the Natural Resources Conservation Service (NRCS) PLANTS database for inclusion in the new 'Pollinators' section.

Pollen will be collected from anthers of flowers, and immediately frozen at -80 degrees celcius until analyzed. Nutritional analyses will be conducted using previously published protocols developed in our laboratory. Briefly, protein concentrations will be estimated using a bicinchoninic acid (BCA) analysis, while fatty acid concentrations will be determined using a chromic acid oxidation assay. Amino acids (AAs) will be quantified after fluoroalkyl chloroformate derivatization using an EZFAAST amino acid hydrolysate kit. All essential amino acids except tryptophan and cysteine will be characterized after acid hydrolysis. Glutamine and asparagine will be converted by acidic conditions to their acid equivalents glutamic acid and aspartic acid. Tryptophan will be extracted separately after base hydrolysis and characterized by fluoroalkyl chloroformate derivatization. Cysteine residues will be quantified after phenylisothiocyanate (PITC) derivatization. Individual fatty acids will be analyzed by fatty acid methyl ester (FAME) analysis after conversion to their methyl ester equivalents. FAME compounds will be quantified by comparison of characteristic mass fragments (m/z) with known amounts of authentic standards. The fraction of the total sample injected will be calculated from the amount of internal standard (pentadecanoic acid) detected in each injected sample.