Influence of the commercial processing and floral origin on bioactive and nutritional properties of honeybee‐collected pollen

Pollen is characterised for having a low fat content, a relatively high content of dietary fibre and an important amount of minerals and essential amino acids. With regard to bioactive compounds, honeybee‐collected pollen exhibits an important source of phytochemical compounds and antioxidant activity. The purpose of this research was to study how the nutritional properties and the stability of the bioactive compounds found in honeybee‐collected pollen were affected by the commercial processing and its floral origin. To achieve this goal, pollen pellets of different floral origin were harvested directly from hives and immediately stored at ?80 °C. Pollen pellets were dried by placing them into hot‐air chambers (traditional drying methodology) or by means of freeze‐drying. We found a slight influence of floral origin on the nutritional properties of pollen pellets (multifloral pollen had higher contents of fat, carbohydrates, proteins and mineral elements than monofloral‐type pollen), whereas the abundance of bioactive compounds was correlated with the origin factor as well as the methodology employed to dry the fresh pollen pellets, especially carotenoid pigments such as lutein (5.73 ± 1.80, 4.93 ± 1.16 and 0.81 ± 0.16 μg of lutein per g of pollen for fresh, lyophilised and hot‐air‐dried multifloral pollen).     

Honeybee corpses as an available source of chitin

Corpses of naturally died honeybees were used as a raw material for chitin isolation. Process of deproteinization of the powder made from clean bee corpses was carried out in the presence of 1M NaOH at 80°C. Influence of time of alkaline treatment on the yield and molar mass of chitin was studied and optimal conditions of proteins removal were found. Process of final depigmentation of protein‐free remainders was carried out using oxidization–reduction reagents. Dependences of the yield of reaction and molar mass of the obtained chitin samples from concentration of oxidizing agent KMnO₄ and from time of discoloring treatment were determined. Final product—high quality chitin with molar masses in range from 318 × 10³ to 424 × 10³ Da—was obtained in amount of 18% from initial mass of honeybee corpses. Chemical structure of chitin was determined in ¹H NMR investigation. It was found that honeybee chitin has high degree of acetylation of about 96%. FTIR spectra of honeybee chitin did not differ from FTIR spectrum of control sample of shrimps chitin with degree of acetylation about 95%. Results of quantitative determination of isolated chitin and its molar characteristic showed that applied treatment of honeybee corpses allowed to acquire successfully chitin of high quality in wide range of molar masses. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

蜂花粉生物活性物质的研究进展

蜂花粉含有多种必需氨基酸、不饱和脂肪酸、黄酮类化合物和多糖等活性物质,具有多种生理功能,如抗氧化、抗癌、降低胆固醇和增强免疫等作用。本文综述了蜂花粉中的生物活性物质及其生理功能的研究进展。同时,对蜂花粉保健食品和药品的开发方向进行了展望。     

Discovery of 3-methyl-2-buten-1-yl acetate,a new alarm component in the sting apparatus of Africanized honeybees

We analyzed the alarm pheromone components from five colonies of Africanized honeybees and three colonies of European honeybees collected in Mexico. Analyses revealed a novel alarm pheromone component that was only present in appreciable quantities in the Africanized bee samples. Analysis of the mass spectrum and subsequent synthesis confirmed that this compound is 3-methyl-2-buten-1-yl acetate (3M2BA), an unsaturated derivative of IPA. In Africanized honeybees, sampling from stings of guards showed that 3M2BA was present at levels of 0–38% the amount of isoamyl acetate (IPA). Behavioral assays from three colonies each of Africanized and European bees showed that 3M2BA recruited worker bees from hives of both Africanized bees and European bees at least as efficiently as isopentyl acetate IPA, a compound widely reported to have the highest activity for releasing alarm and stinging behavior in honeybees. However, a mixture of of 3M2BA and IPA (1:2) recruited bees more efficiently than either of the compounds alone. None of the compounds differed in their efficacy for inducing bees to pursue the observers.     

Responsiveness to inhibitory signals changes as a function of colony size in honeybees (Apis mellifera)

Biological collectives, like honeybee colonies, can make intelligent decisions and robustly adapt to changing conditions via intricate systems of excitatory and inhibitory signals. In this study, we explore the role of behavioural plasticity and its relationship to network size by manipulating honeybee colony exposure to an artificial inhibitory signal. As predicted, inhibition was strongest in large colonies and weakest in small colonies. This is ecologically relevant for honeybees, for which reduced inhibitory effects may increase robustness in small colonies that must maintain a minimum level of foraging and food stores. We discuss evidence for size-dependent plasticity in other types of biological networks.     

Functional amphiphilic block copolyethers as carriers of caffeic acid phenethyl ester

Amphiphilic diblock copolymers consisting of hydrophilic polyglycidol (PG) and hydrophobic poly(allylglycidyl ether) (PAGE) were prepared by sequential anionic ring‐opening polymerization of allylglycidyl ether and ethoxyethyl glycidyl ether followed by removal of the protective ethoxyethyl groups. The polymerization was initiated by partially deprotonated dodecanol and performed in solvent‐free conditions. The copolymers were composed of a hydrophobic dodecyl residue attached to a block of PAGE with a fixed degree of polymerization (dp = 44) and differing in length of the PG block (dp = 16 and 66, corresponding to PG contents of 25 and 60 mol%, respectively). The two copolymers were spontaneously soluble in water. Above a certain critical concentration, they formed well‐defined self‐assembled nanoparticles. Their characterization parameters were determined by static and dynamic light scattering. The aggregates of the more hydrophobic copolymer, C₁₂‐PAGE‐PG25, were characterized by considerably larger dimensions and molar mass, reaching 78.6 nm and 253.0 × 10⁶ g mol^?1, respectively, than those of the more hydrophilic copolymer, C₁₂‐PAGE‐PG60. The hydrophobic moieties were proved to create a favorable environment for solubilization of caffeic acid phenethyl ester (CAPE) (the main active ingredient of propolis with cytotoxic and antioxidant activities), whereas the numerous hydroxyl groups from the PG moieties brought additional benefits related to the biocompatibility of the copolymers. Preliminary experiments with L929 fibroblast cells showed that the aggregates displayed no signs of toxicity in the applied in vitro test system, suggesting their appropriateness as a drug delivery platform. The CAPE‐loaded aggregates, however, showed dose‐dependent cytotoxic effects, indicating that CAPE retained its cytotoxic activity. © 2019 Society of Chemical Industry     

Identification of kakusei,a Nuclear Non-Coding RNA,as an Immediate Early Gene from the Honeybee,and Its Application for Neuroethological Study

The honeybee is a social insect that exhibits various social behaviors. To elucidate the neural basis of honeybee behavior, we detected neural activity in freely-moving honeybee workers using an immediate early gene (IEG) that is expressed in a neural activity-dependent manner. In European honeybees (Apis mellifera), we identified a novel nuclear non-coding RNA, termed kakusei, as the first insect IEG, and revealed the neural activity pattern in foragers. In addition, we isolated a homologue of kakusei, termed Acks, from the Japanese honeybee (Apis cerana), and detected active neurons in workers fighting with the giant hornet.     

Regional brain variations of cytochrome oxidase staining during olfactory learning in the honeybee (Apis mellifera).

Regional brain variations of cytochrome oxidase (CO) staining were analyzed in the honeybee (Apis mellifera) after olfactory conditioning of the proboscis extension reflex. Identification of brain sites where stimuli converge was done by precise image analysis performed in antennal lobes (AL) and mushroom bodies (MB). In Experiment 1, bees received 5 odorant stimulations that induced a transient decrease of CO activity in the lateral part of the AL. In Experiment 2, bees were trained with 5-trial olfactory conditioning. CO activity transiently increased in the lips of the MB calyces. There was also a delayed increase in the lateral part of the AL. An olfactory stimulus presented alone and an odor paired to a sucrose stimulation are treated by different pathways, including both AL and MB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cuticle alkanes of honeybee larvae mediate arrestment of bee parasiteVarroa jacobsoni

The ectoparasitic miteVarroa jacobsoni invades worker brood cells of the honeybeeApis mellifera during the last 20 hr before the cells are sealed with a wax cap. Cuticle extracts of 8-day-old worker honeybee larvae occupying such brood cells have an arrestment effect on the mite. The mites run for prolonged periods on the extract, systematically returning onto the stimulus after touching the borders of the treated area. Mites increase walking speed and path straightness in response to increasing doses of a nonpolar fraction of the cuticle extract. Saturated straight-chain odd-numbered C₁₉–C₂₉ hydrocarbons were identified by thin-layer argentation chromatography and gas chromatography-mass spectrometry as the most active constituents, with branched alkanes also contributing to the arrestment effect of this active fraction. Analysis of the behavior responses to syntheticn-alkanes indicate that the response is probably based on a synergism between the different alkane components of the fraction rather than to an individual compound.