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PubMed2004

Preparation and functional properties of extracts from bee bread.

Three extracts, namely hot-water fraction (HWF), water-soluble fraction (WSF), and ethanol-soluble fraction (ESF), were prepared from fresh bee bread imported from Lithuania. The protein and total phenolic contents of these samples were very high. Among them, WSF at 100% concentration showed the highest antioxidative ability and scavenging ability. On the other hand, ESF at 10% concentration possessed the highest ability against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. Bee bread will apply more and more as health food and medicine due to its functional properties such as antioxidative ability and scavenging activities of reactive oxygen species.

Anti-Infective Agents↗
PubMed2002

Susceptibility of Prevotella intermedia/Prevotella nigrescens (and Porphyromonas gingivalis) to propolis (bee glue) and other antimicrobial agents.

Black-pigmented gram-negative anaerobes such as Porphyromonas gingivalis and Prevotella intermedia are suspected pathogens in adult periodontitis, whereas Prevotella nigrescens has been associated with health. Antimicrobial resistance among bacteria from this group has been reported in the past decade. This research aimed to evaluate and compare the susceptibility profile of 17 P. intermedia/P. nigrescens isolates recovered from patients with periodontitis and three reference strains to six antimicrobials, prescribed in dentistry in Brazil, and propolis (bee glue). The antimicrobial agents tested were tetracycline, penicillin, clindamycin, erythromycin, metronidazole, meropenem and six ethanolic extracts of propolis (EEPs) from Brazil. The reference strains P. gingivalis ATCC 33277 and P. intermedia ATCC 25611 were used for determination of minimum bactericidal concentration (MBC) and for time-kill assay to the EEPs. All of the strains were susceptible to penicillin, erythromycin, meropenem, metronidazole and 95% of them (n=19) to tetracycline. Thirty six percent (n=7) of the P. intermedia/P. nigrescens strains tested were resistant to clindamycin. As for propolis activity, all strains were susceptible and the minimum inhibitory concentration values ranged from 64 to 256 microg/mL. For the reference strains P. gingivalis ATCC 33277 and Prevotella intermedia ATCC 25611 the MBC was 256 microg/mL and death was observed within 3 h of incubation for P. gingivalis and within 6 h for P. intermedia. The action of propolis (bee glue) against suspected periodontal pathogens suggests that it may be of clinical value.

Journal Article↗
PubMed1997

Unequal subfamily proportions among honey bee queen and worker brood

Queens from three colonies of feral honey bees, Apis mellifera were removed and placed in separate nucleus colonies. For each colony, eggs and larvae were taken from the nucleus and placed in the main hive on each of 3-4 consecutive weeks. Workers in the queenless parts selected young larvae to rear as queens. Queen pupae, together with the surrounding worker pupae, were removed from each colony and analysed at two to three microsatellite loci to determine their paternity. In all three colonies, the paternity of larvae chosen by the bees to rear as queens was not a random sample of the paternities in the worker brood, with certain subfamilies being over-represented in queens. These results support an important prediction of kin selection theory: when colonies are queenless, unequal relatedness within colonies could lead to the evolution of reproductive competition, that is some subfamilies achieving greater reproductive success than others. The mechanism by which such dominance is achieved could be through a system of kin recognition and nepotism, but we conclude that genetically based differential attractiveness of larvae for rearing as queens is more likely.Copyright 1997 The Association for the Study of Animal BehaviourCopyright 1997The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1998

Effects of relatedness on queen competition within honey bee colonies

The influence of relatedness on the pre- and post-emergent survival of honey bee queens was investigated. Workers did not preferentially rear sisters over non-siblings under conditions of natural queen replacement. After queen emergence, however, there was a significant effect of a queen's relatedness to the workers on her survivorship during fights with rival queens. The mechanism of this bias towards related queens is unknown, and several hypotheses are discussed. The difference in post-emergent survivability suggests that kin selection may operate during competition among adult queens at this crucial stage of honey bee reproduction. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1986

Free amino acids in bee hive product (propolis) as identified and quantified by gas-liquid chromatography.

Propolis is a natural resinous product collected by honey bees and containing, among other biochemical constituents, a variety of free amino acids. Acid extraction and quantification of these amino acids by gas-liquid chromatography reveals that their total concentration in this honey bee product is over 40% w/w, and that arginine and proline constitutes over 50% of the crude acid extract. As propolis was shown to stimulate mammalian tissue regeneration, we suggest that the physiological significance of arginine in the propolis product lies in its ability to stimulate mitosis and to enhance protein biosynthesis, and that the biochemical importance of proline in it, stems from its capability to promote build-up of collagen and elastin, two essential components in the matrix of connective tissues.

Amino Acids↗
PubMed1993

Possible mechanisms of action of cobra snake venom cardiotoxins and bee venom melittin.

Cobra snake venom cardiotoxins and bee venom melittin share a number of pharmacological properties in intact tissues including hemolysis, cytolysis, contractures of muscle, membrane depolarization and activation of tissue phospholipase C and, to a far lesser extent, an arachidonic acid-associated phospholipase A2. The toxins have also been demonstrated to open the Ca2+ release channel (ryanodine receptor) and alter the activity of the Ca(2+)+Mg(2+)-ATPase in isolated sarcoplasmic reticulum preparations derived from cardiac or skeletal muscle. However, a relationship of these actions in isolated organelles to contracture induction has not yet been established. The toxins also bind to and, in some cases, alter the function of a number of other proteins in disrupted tissues. The most difficult tasks in understanding the mechanism of action of these toxins have been dissociating the primary from secondary effects and distinguishing between effects that only occur in disrupted tissues and those that occur in intact tissue. The use of cardiotoxin and melittin fractions contaminated with trace ('undetectable') amounts of venom-derived phospholipases A2 has continued to be common practice, despite the problems associated with the synergism between the toxins and enzymes and the availability of methods to overcome this problem. With adequate precautions taken with regard to methodology and interpretation of results, the cobra venom cardiotoxins and bee venom melittin may prove to be useful probes of a number of cell processes, including lipid metabolism and Ca2+ regulation in skeletal and cardiac muscle.

Animals↗
PubMed2001

Thermoregulation of dancing bees: thoracic temperature of pollen and nectar foragers in relation to profitability of foraging and colony need.

The thorax surface temperature of dancing honeybees (Apis mellifera carnica) recruiting nestmates to natural sources of nectar and pollen around Graz (Austria) was measured by real-time infrared thermography without touching them or disturbing social interactions. Thorax temperature during dancing was quite variable (31.4-43 degrees C). In the course of a foraging season it varied considerably and was always lower than in bees foraging from a highly profitable food source (2 molar sucrose 120 m from the hive). It averaged 38.0 degrees C (SD=2.24, n=224 dances) in the nectar foragers and 37.4 degrees C (SD=1.64, n=171) in the pollen foragers, resembling that of dancers foraging 0.5 molar sucrose from feeders with unlimited flow. Hive air temperature accounted only for about 3-8% of total variation. Foraging distance modulated dancing temperature in a way that, according to the decrease of the profitability of foraging with distance, maximum temperatures decreased and, in accordance with the increase of the dancing threshold with distance, minumum temperatures increased with distance, this way providing new support for the hypothesis that the dancing temperature is modulated by the profitability of foraging and the dancing and foraging motivation of the bees. Dancing temperature of both nectar and pollen dancers correlated with several parameters of the hive status, increasing with the amount of brood and decreasing with the amount of honey and pollen. These correlations are discussed with respect to literature reports on a colony's need for pollen and nectar, in particular the effect of brood and the amount of pollen on pollen foraging, and the effect of honey stores and demand for nectar on nectar foraging.

Journal Article↗
PubMed2002

Secretions of stingless bees: cephalic secretions of two Frieseomelitta species.

Gas chromatographic and mass spectrometric analysis of the volatile compounds in the mandibular glands of Frieseomelitta varia and the heads of Frieseomelitta silvestrii have revealed relatively simple or more complex mixtures of volatile oxygenated compounds. 2-Alkanols were found to be important components for both species. In F. varia the composition was essentially the same in samples from two widely separated areas and there were small differences between callows and mature, foraging bees. The first electroantennographic studies on stingless bees, using hexane extracts of heads of both species, have demonstrated a response in the workers' antennae to these, as well as to the pure compounds 2-heptanol and 2-nonanol.

Journal Article↗
PubMed1997

Mandibular Gland Volatiles and Their Ontogenetic Patterns in Queen Honey Bees, Apis mellifera carnica.

Extracts of mandibular glands taken from adult queens of the honey bee, Apis mellifera carnica, were analysed by gas chromatography-mass spectroscopy. More than 100 compounds could be identified among which oxygenated fatty acids with six, eight, 10 and 12 carbon atoms are particularly interesting since they show structural relationships to the queen substance, (E)-9-oxo-2-decenoic acid. Changes in the patterns of volatiles were followed up from emergence until the full dominant status of an egg-laying queen in a strong colony. Generally, the amount of volatiles per gland was found to increase with age. The final level of queen substance (9-ODA) content is reached at the postmating stage about 10 days after emergence. Ontogenetic patterns of concentrations were determined for those components regarded to predominantly contribute to the royal pheromone. Characteristic compositions of signals, possibly involved in the premating, mating and postmating dominance status of a honey bee queen are discussed. Copyright 1997 Elsevier Science Ltd. All rights reserved

Journal Article↗
PubMed2000

Responsiveness of honey bee (Apis mellifera L.) corpora allata to allatoregulatory peptides from four insect species.

Five neuropeptides with known allatotropic or allatostatic activity in other insect species were examined for their effects on honey bee corpora allata. Using an in vitro radiochemical assay, we assessed the ability of these peptides to affect the biosynthesis of juvenile hormone III and its immediate precursor methyl farnesoate, as well as their effects on the conversion of methyl farnesoate into juvenile hormone. None of the allatostatins tested affected JH biosynthesis during the last larval instar of honey bee workers. Manduca sexta allatotropin, however, stimulated JH biosynthesis in a stage-specific and dose-dependent manner. Analysis of intraglandular contents of juvenile hormone and its precursor revealed that the allatotropin significantly increased JH precursor but did not overcome the stage-specific block in the terminal step of JH biosynthesis that is typical for early fifth-instar worker larvae. Studies also indicated that the allatotropic effect was reversible at the level of methyl farnesoate production.

Journal Article↗
PubMed1998

Antibody responses to bee melittin (Api m 4) and hornet antigen 5 (Dol m 5) in mice treated with the dominant T-cell epitope peptides.

BACKGROUND: Mice treated with the dominant T-cell epitope peptides of allergens were reported to have reduced peptide or allergen-specific T-cell responses on subsequent immunization, but the extent of reduction of allergen-specific antibodies is not clear. OBJECTIVE: This study was done to compare the extent of reduction of T-cell and antibody responses in peptide-treated mice. Two allergens were tested. Bee melittin (Api m 4), an allergen of 26 amino acid residues, has a single dominant T- or B-cell epitope. Hornet antigen 5 (Dol m 5), an allergen of 204 amino acid residues, has multiple dominant T- or B-cell epitopes. METHODS: Mice were treated with T-cell peptides of Api m 4 or Dol m 5 and then immunized biweekly with their respective allergen with alum adjuvant. T-cell peptides tested were residues 7-19 of Api m 4 and residues 41-60, 141-160, and 176-195 of Dol m 5. T-cell responses at week 9 or 11 were assayed by proliferation of spleen cell cultures. Antibody responses of different isotypes were measured biweekly by ELISA. RESULTS: Partial reduction of 30% to 50% of T-cell responses to peptide or allergen was observed in bee and hornet peptide-treated mice. About 65% reduction of Api m 4-specific antibody response was observed early in the immune response but gradually subsided to about 40% late in the response. Partial reduction of about 40% of Dol m 5-specific antibody response was only observed early in the immune response. CONCLUSION: Peptide treatment is partially effective in the reduction of T-cell responses of univalent or multivalent allergens. It is also partially effective in the reduction of antibody response of a univalent allergen, but it is poorly effective for a multivalent allergen.

Adjuvants, Immunologic↗
PubMed2006

Determinants of population biology of the chewing louse Brueelia apiastri (Mallophaga, Philopteridae) on the European bee-eater (Merops apiaster).

In this study we examine the population biology of Brueelia apiastri, a chewing louse living on the European bee-eater (Merops apiaster). We investigate the relationships between parasite intensity of infestation, sex ratio, reproductive output, parasite size and their environment i.e. the morphology, condition, age and sex of the host. Chewing lice were collected, their sex and age (developmental stage) identified and parasite body size determined as a measure of parasite condition (larger individuals consume larger meals and larger females may produce larger clutches). The data show that there is variation in intensity as well as body size of B. apiastri between individual bee-eaters and this variation is independent of the sex of the birds. However, size, condition and age of the birds seem to influence the infestation rates with B. apiastri. The study suggested size-dependent depredation, since more, smaller chewing lice (usually nymphs) living on birds in better condition and birds having longer bills. Furthermore, more male chewing lice (males are smaller than females) live on older birds. Intraspecific competition between parasites seems to have a negative effect on female but not male body size but this result could be also explained by size-dependent depredation.

Age Factors↗
PubMed1990

Trophallaxis in a communal halictine bee Lasioglossum (Chilalictus) erythrurum.

Food exchange by means of oral trophallaxis was confirmed for a communal halictine bee Lasioglossum (Chilalictus) erythrurum. These results demonstrate an independent evolution of trophallaxis in bees. The occurrence of trophallaxis in a communal species questions the role of trophallaxis in the evolution of sociality. Neutral arena encounters between one fed and one unfed female indicate that food exchange is not associated with familiarity. Donor females fed nestmates and nonnestmates in the same proportion, even when nonnestmates were from a separate nest aggregation located 7 km away. Such universal acceptance is expected if positive fitness benefits accrue from nearly all interactions with conspecifics in nature.

Journal Article↗
PubMed2005

An Overview of Bee Venom Acupuncture in the Treatment of Arthritis.

Bee venom acupuncture (BVA), as a kind of herbal acupuncture, exerts not only pharmacological actions from the bioactive compounds isolated from bee venom but also a mechanical function from acupuncture stimulation. BVA is growing in popularity, especially in Korea, and is used primarily for pain relief in many kinds of diseases. We aimed to summarize and evaluate the available evidence of BVA for rheumatoid arthritis and osteoarthritis. Computerized literature searches for experimental studies and clinical trials of BVA for arthritis were performed on the databases from PUBMED, EMBASE and the Cochrane Library. In addition, two leading Korean journals (The Journal of Korean Society for Acupuncture and Moxibustion and The Journal of Korean Oriental Medicine) were searched for relevant studies. The search revealed 67 studies, 15 of which met our criteria. The anti-inflammation and analgesic actions of BVA were proved in various kinds of animal arthritic models. Two randomized controlled trials and three uncontrolled clinical trials showed that BVA was effective in the treatment of arthritis. It is highly likely that the effectiveness of BVA for arthritis is a promising area of future research. However, there is limited evidence demonstrating the efficacy of BVA in arthritis. Rigorous trials with large sample size and adequate design are needed to define the role of BVA for these indications. In addition, studies on the optimal dosage and concentration of BVA are recommended for future trials.

Journal Article↗
PubMed2006

Genetic breeding system and investment patterns within nests of Dawson's burrowing bee (Amegilla dawsoni) (Hymenoptera: Anthophorini).

Dawson's burrowing bee is a large solitary ground-nesting bee endemic to the arid zone of Western Australia. In this study, we use microsatellite markers to analyse the genotypes of offspring from individual nests to determine the number of effective mates for each female. From these data we have determined that females almost certainly mate only once which is consistent with male reproductive tactics that include protandry and intense male-male competition for access to virgin females. We also use the molecular data to show that the nesting female is the mother of all the offspring of her nest and that brood parasitism is unlikely in this species. The data indicate that females make daughters at the beginning of the season followed by large sons in the middle, and then small sons at the end. Females often place one brood cell directly above another. The distribution of sex and morph in these doublets follows a pattern with most containing a female on the bottom and a minor male on the top, followed by almost equal numbers of female on top of female and minor male on top of major male. This pattern is likely favoured by emergence patterns, with males emerging before females and minor males emerging before major males. We suggest that although minor males have low reproductive success, their production may nonetheless be beneficial in that minor males open up emergence tunnels for their larger and reproductively more valuable siblings. In addition, minor males may be a best of a bad job product arising from changes in the costs to nesting females of gathering brood provisions over the course of the flight season.

Animals↗
PubMed1994

The architect and the bee: some reflections on postmortem pregnancy.

Do physicians have a duty to sustain the pregnancies of women who die during the first or second trimester? Physicians cannot simply assume that the woman would have wished the pregnancy to continue, nor (in the U.S., at any rate) is it clear that the state has any interest in fetal life before viability. The conditions for beneficence-based duties of fetal rescue will often be unmet, both because sustaining the pregnancy is not always a clear gain to the born child and because it may impose a substantial burden on the benefactor. And duties of special relationship cannot readily be applied in these cases, as it is difficult to see how the relationship between someone who no longer exists and someone who does not yet exist can breed special duties. Further, to draw on Marx's distinction between the architect, who builds purposefully, and the bee, who cannot help what she is doing, I argue that human pregnancy is in a number of respects purposeful, creative, and deliberate, and that postmortem pregnancy, which follows the model of the bee, is a destructive icon that undercuts women's agency.

Altruism↗
PubMed1980

Spore Load of Ascosphaera Species on Emerging Adults of the Alfalfa Leafcutting Bee, Megachile rotundata.

The spore load of Ascosphaera species spores on larval chalkbrood cadavers and newly emergent adults of the alfalfa leafcutting bee, Megachile rotundata, was determined. The spore content of chalkbrood cadavers ranged from 3 x 10 to 5 x 10. Adults emerging through zero to nine cadavers carried spores on all body parts examined by scanning electron microscopy. Estimates of the total number of spores obtained from a series of adult washes ranged from 9 x 10 to 8 x 10. Some adult males which emerged through no cadavers carried 10 to 10 spores, indicating that nesting materials might also have been contaminated. However, the control of chalkbrood in commercial bee populations may not be accomplished simply by providing clean nesting materials as adults may still emerge through diseased larvae.

Journal Article↗
PubMed1996

The knowledge base of bee navigation

Navigation in honeybees is discussed against the background of the types of memories employed in the navigational task. Two questions are addressed. Do bees have goal-specific expectations, and when are novel routes travelled? Expectations are deduced from (1) context stimuli as determinants for local cue memories, (2) landmark-dependent path integration, (3) sequential learning of landmarks, and (4) motivation- and context-dependent memory retrieval. Novel routes are travelled under two conditions: (1) goal-cue-based piloting and (2) integration of simultaneously activated vector memories. Our data do not support the conclusion that memory integration in bees is organised by a cognitive map. The assumption of purely separate memories that are only retrieved according to the chain of events during navigational performance also appears to be inadequate. We favour the view that multiple memories are integrated using external and internal sources of information. Such configural memories lead to both specific expectations and novel routes.

Journal Article↗