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The nutritional and chemical properties of three Chinese pollens, sorghum (Sorghum sp.), rapeseed (Brassica napus) and sunflower (Helianthus annuus), were studied. All three pollens were highly preferred, with sunflower pollen the highest, by young honey bees (Apis mellifera). Rapeseed pollen increased honey bee's longevity the greatest; however, sorghum and sunflower pollens also increased the longevity relative to the no-pollen group. All three pollens had high energy (about 5 kcal/g) and carbohydrate quantities (58%). The protein, fat, and fiber levels were 27%, 7%, and 9% in rapeseed pollen, 26%, 5%, and 13% in sorghum pollen, and 15%, 5%, and 10% in sunflower pollen. alpha-Tocopherol was high in sunflower pollen (61 μg/g), lower in rapeseed (33 μg/g) and sorghum pollen (15 μg/g). K, Ca, Mg, Fe, Cu, and Mn were high in all three pollens. These data suggest that a pollen which is highly preferred by honey bees is not necessarily the most nutritious.

Vitamin E (α-TH), the primary lipid soluble antioxidant, can protect tissues from oxidative insult. Oxidant-producing pulmonary alveolar macrophages (PAM), may depend on α-TH to prevent oxidative damage. α-TH levels in cultured PAM declined rapidly during the first 12-18 hours in culture. Approximately 60% of the decrease was detected as unoxidized alpha-TH released to RPMI 1640 (containing 5% fetal bovine serum (FBS)) culture medium. α-TH was not detected in serum-free Ham's F12 medium. PAM appeared to reabsorb α-TH from the medium. PAM activation with phorbol myristate acetate (PMA) did not affect cellular α-TH depletion. However, the amount of α-TH detected in the medium of PMA treated cultures was only 50% of that detected in medium from untreated controls. Inhibition of superoxide production with iodoacetate had no effect on cellular depletion kinetics, however medium α-TH levels were still 50% of controls. Inhibition of nitric oxide, synthesis appeared to have no effect on α-TH status.

Marine oils contain eicosapentaenoic acid, a fatty acid that competes for cyclooxygenase and reduces the synthesis of dienoic prostanoids including prostaglandin E2 (PGE2). Since PGE2 plays an important role in the release of hypothalamic GnRH and the maturation of ovarian follicles and ova release, it was postulated that a diet containing fish oil (FO) would delay first ovulation through inhibitory effects on GnRH release, follicle development and ovulation. Immature female Sprague-Dawley rats were fed a FO diet ad libitum. Controls were pair-fed an identical diet with the substitution of safflower oil. The age of the FO-fed rats was significantly increased at first estrus, and first ovulation was either delayed or inhibited. Preoptic area/hypothalamic and ovarian PGE2 levels were reduced by FO feeding whereas hypothalamic GnRH was significantly increased. A FO-containing diet may delay the onset of puberty through attenuation of preovulatory GnRH release and local impairment of the ovulatory process.