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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Antibacterial and phytochemical studies of selected South African honeys on clinical isolates of Helicobacter pylori

Manyi-Loh, Christy E January 2012 (has links)
Infection with Helicobacter pylori has been associated with the pathogenesis of numerous stomach and gastroduodenal diseases that pose threats to public health. Eradicaftion of this pathogen is a global challenge due to its alarming rate of multidrug resistance. Consequently, to find an alternative treatment, the search is increasingly focused on new antimicrobial product from natural sources including honey. Honey has been used as medicine in several cultures since ancient time due to its enormous biomedical activities. Its beneficial qualities have been endorsed to its antimicrobial, antioxidant, anti-inflammatory properties added to its phytocomponents. In this study, the anti-H. pylori activity of South African honeys and their solvent extracts as well as the phytochemicals present in the two most active honeys were evaluated. Agar well diffusion test was used to investigate the antimicrobial activity of six honey varieties obtained from different locations in the country. Subsequently, the honeys were extracted with four organic solvents viz n-hexane, diethyl ether, chloroform and ethyl acetate employed in order of increasing polarity. The antibacterial activity of the different solvent extracts of each honey was evaluated by agar well diffusion; broth micro dilution and time kill assays. Different chromatographic techniques (Thin layer & column chromatography) were employed to enumerate the phytochemical constituents in the most active solvent extracts of Pure Honey (PH) and Champagne Royal Train (CRT); and were identified by gas-chromatography linked mass-spectrometry. Linalool pure compound was equally evaluated for anti-H. pylori activity in a bid to trace the antibacterial agent among the variety of compounds identified. Data were analyzed by One-way ANOVA test at 95% confidence interval. Crude honeys and their solvent extracts demonstrated potent anti-H. pylori activity with zone diameter that ranged from [16.0mm (crude) to 22.2mm (extract)] and percentage susceptibilities of test isolates between 73.3% (crude) and 93.3% (extract). The chloroform extracts of PH and CRT were most active with MIC50 in the ranges 0.01- viii 10%v/v and 0.625-10%v/v respectively, not significantly different from amoxicillin (P> 0.05); and efficient bactericidal activity (100% bacterial cells killed) at 1/2MIC and 4xMIC over different time intervals, 36-72hrs and 18-72hrs respectively. The appearance of bands on the thin layer chromatography (TLC) chromatogram spotted with the chloroform extracts of PH and CRT; and developed with hexane: ethyl acetate: acetic acid (HEA) and methanol: acetic acid: water (MAAW) solvent systems indicated the presence of compounds. Purification of the compounds contained in these extracts over silica gel column yielded numerous fractions which were evaluated for antibacterial activity and purity. PHF5 was the most active fraction with a mean MIC50 value of 1.25mg/mL. Volatile compounds belonging to different known chemical families in honey were identified in all the active fractions obtained from PH. Conversely, only four compounds were identified in the active fractions obtained from CRT hence the non volatile constituents could be of prime relevance with respect to antibacterial activity of this honey. Of novelty was the presence of thiophene and N-methyl-D3-azirdine compounds, essential precursors used for the synthesis of natural products and pharmaceuticals with vital biomedical properties. Linalool demonstrated potent inhibitory (MIC95, 0.002- 0.0313mg/mL) and bactericidal activity (0.0039-0.313mg/mL) against the test isolates. On the other hand, a significant difference was recorded (P < 0.05) in comparing the activity of linalool compound to the fractions. PH could serve as a good economic source of bioactive compounds which could be employed as template for the synthesis of novel anti-H. pylori drugs. However, further studies are needed to determine the non volatile active ingredients in PH and CRT as well as toxicological testing
142

Ressources pollinifères et mellifères de l'Abeille domestique, Apis Mellifera, en paysage rural du nord-ouest de la France / Polliniferous and melliferous resources available for honeybees (Apis mellifera) in a rural landscape of North-Western France

Piroux, Mélanie 21 October 2014 (has links)
Depuis le début du XXème siècle, l’évolution de l’agriculture et l'intensification des pratiques agricoles ont conduit à des modifications profondes du paysage induisant des pertes importantes d’habitats naturels et semi-naturels. Ces changements, entraînant notamment la diminution des ressources végétales et impliquant l'utilisation systématique de pesticides, ont des répercussions sur les colonies d’abeilles. C’est dans ce contexte que, durant deux saisons apicoles, des inventaires botaniques ont été réalisés au sein de l’aire de butinage de deux ruchers situés en paysage de grande culture du nord-ouest de la France et que des échantillons de pelotes de pollen et de miels prélevés dans ces ruchers ont été analysés. L’objectif était de comparer les ressources floristiques disponibles et celles réellement exploitées par les abeilles et d’entrevoir les stratégies de butinage mises en place dans ce cadre paysager. Les relevés floristiques ont permis de distinguer d’une part, de larges surfaces d’espèces cultivées, à floraison ponctuelle et d’autre part, des surfaces non cultivées, de plus petite taille, occupées par de nombreuses espèces sauvages dont la floraison s’étale sur la totalité de la saison apicole. Les analyses palynologiques montrent que ces espèces floristiques sauvages sont exploitées en continu y compris pendant la période de floraison des espèces cultivées. Bien que cette étude ne soit pas en mesure de le démontrer, il est possible que les espèces sauvages procurent aux colonies un apport nutritionnel que la floraison ponctuelle des plantes cultivées ne peut totalement compenser. Une meilleure connaissance de la valeur nutritionnelle des différents pollens d’essences végétales, ainsi que des besoins alimentaires basiques nécessaires au développement et à la pérennisation des colonies devraient aider à éprouver cette hypothèse. / Since the beginning of the XXth century, the evolution of agriculture and the intensification of farming practices have led to landscape changes with the loss of natural and semi-natural habitats. These changes, involving a decrease of plant resources and a use of pesticides, may have noticeable impact on honey bee colonies. In this framework of weakened biodiversity, the initiative was taken of recording botanical species growing in the foraging area of two apiaries in cultivated landscapes of Western France and sampling pollen pellets and honey for pollen species determination during two successive beekeeping seasons. The aim of this study was to compare the available flora resources with those really exploited by the honey bees, to get a glimpse of the foraging strategies developed by the colonies in this landscape context. The floristic readings enabled to distinguish wide areas of cultivated plant species characterized by temporary blossoms from areas of wild species characterized by much smaller superficies and by flowerings spread over the year. Palynological analyses indicate that wild floristic species are exploited throughout the beekeeping season including during blooms of cultivated plant species. Even though not conclusively stated by the present study, it is possible that wild species provide colonies with nutritional intakes that cannot be totally compensated by temporary blooms of cultivated plants. A more extended knowledge of the nutritional values of pollens produced by plant species together with a better understanding of basic food needs for development and perennisation of colonies should help to test this hypothesis.
143

Study of airborne particulate matter (PM) contaminating the honey bee Apis mellifera Linnaeus, 1758 and bee products

PAPA, GIULIA 25 March 2021 (has links)
Apis mellifera Linnaeus (1758) è un insetto eusociale conosciuto in tutto il mondo sia per la produzione di miele sia per il suo ruolo di impollinatore, uno dei servizi ecosistemici fondamentali per la biodiversità del pianeta. Durante la sua attività di foraggiamento, l’ape è esposta agli inquinanti ambientali tra cui il particolato atmosferico aerodisperso (PM). Il particolato atmosferico può depositarsi sul corpo dell’insetto e infine contaminare anche i prodotti apistici come polline e miele. Il PM può avere diverse dimensioni (es. PM10, PM2.5, PM0.1), composizione chimica, morfologia e fonti di emissione (naturale o antropica). Nel presente elaborato di tesi, tecniche di microscopia elettronica a scansione (SEM-EDX) sono state utilizzate per caratterizzare la contaminazione da PM di origine antropica del corpo dell’ape e dei suoi prodotti (Capitolo 2 e Capitolo 3) e analisi molecolari per studiare gli eventuali effetti sub-letali sul microbiota intestinale di api esposte ai PM per via orale (Capitolo 4). / Apis mellifera Linnaeus (1758) order Hymenoptera family Apidae, is a eusocial insect widely known for its role in pollination, a fundamental ecosystem service for plant biodiversity and ultimately for the planet. During flight and foraging activity, the honey bee can collect airborne particulate matter (PM) on their own body, especially on the forewings, and can also contaminate bee products as pollen and honey. Particulate matter can originate from natural or anthropic sources, and is characterised by size (e.g., PM10, PM2.5, PM0.1), chemical composition, and morphology. In this thesis, honey bee, pollen and honey were used as bioindicator of PM – from coarse to ultrafine – in industrial areas of the Po Valley, Italy (Chapter 2 and Chapter 3). The (sub-lethal) effects of Titanium dioxide – a widespread airborne PM1 pollutant – on the honey bee through oral exposure was then investigated (Chapter 4). The technique used to analyse the PM contaminating bees and bee products is the scanning electron microscopy (SEM) coupled with X-ray spectrometer (EDX). EDX spectra allowed us to obtain chemical information from specimens, while backscattered-electron (BSE) imaging and elemental mapping provided both compositional and topographic information of PM.
144

Characterization of Giant Proteins from Lactobacillus kunkeei

Schol, Martin January 2020 (has links)
Lactobacillus kunkeei is the most common and dominant bacterium in the honey stomach of honeybees. L. kunkeei has been isolated from honeybees all over the world. Genome sequencing has identified 5 genes for exceptionally large proteins in the genome of L. kunkeei. These proteins do not show any similarity to sequences of proteins with a known structure. These giant proteins all have a conserved region of 60 amino acids in their C-terminus. This conservation led to the hypothesis that the C-terminal domains of the giant proteins are important for their function with possibly a role in the attachment to the cell wall. In this study, a total of eight different constructs were made for two of these giant proteins. The boundaries for the constructs were determined based on bioinformatic predictions. The eight constructs all have different start positions and all end at the very C-terminal end of the protein. These constructs were cloned into an expression vector. One of the full-length giant protein was cloned into an expression vector as well.  The C-terminal constructs and the full-length proteins were recombinantly produced in Escherichia coli. Expression of six C-terminal constructs was observed and an attempt was made to purify two of the C-terminal constructs. Expression of the full-length giant protein was observed as well and purification was attempted. Neither the C-terminal constructs nor the full-length giant protein could be purified at full length. The results for the C-terminal constructs show that no folded C-terminal domain has been found for the giant proteins. A purified protein construct of the N-terminal of one of the giant proteins was available. This protein was analyzed using biophysical techniques. Circular dichroism was used to test the thermal stability. The construct did not refold after being thermally denatured. Circular dichroism measurements indicated that the N-terminal construct is composed of a mixture of α-helices and ß-sheets. Small-angle X-ray scattering data indicated that the N-terminal construct had an elongated shape with knot-like parts. Protein crystals have been obtained for the N-terminal construct and these will be analyzed using X-ray diffraction.
145

Draft genome sequences of two Bifidobacterium sp. from the honey bee (Apis mellifera)

Anderson, Kirk, Johansson, Andreas, Sheehan, Tim, Mott, Brendon, Corby-Harris, Vanessa, Johnstone, Laurel, Sprissler, Ryan, Fitz, William January 2013 (has links)
BACKGROUND:Widely considered probiotic organisms, Bifidobacteria are common inhabitants of the alimentary tract of animals including insects. Bifidobacteria identified from the honey bee are found in larval guts and throughout the alimentary tract, but attain their greatest abundance in the adult hind gut. To further understand the role of Bifidobacteria in honey bees, we sequenced two strains of Bifidobacterium cultured from different alimentary tract environments and life stages.RESULTS:Reflecting an oxygen-rich niche, both strains possessed catalase, peroxidase, superoxide-dismutase and respiratory chain enzymes indicative of oxidative metabolism. The strains show markedly different carbohydrate processing capabilities, with one possessing auxiliary and key enzymes of the Entner-Doudoroff pathway.CONCLUSIONS:As a result of long term co-evolution, honey bee associated Bifidobacterium may harbor considerable strain diversity reflecting adaptation to a variety of different honey bee microenvironments and hive-mediated vertical transmission between generations.
146

Pollination ecosystem services to onion hybrid seed crops in South Africa

Brand, Mariette Rieks 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Insect pollination contributes in various degrees toward the production of a variety of agricultural crops that ensure diversity and nutritional value in the human diet. Although managed honeybees (Apis mellifera L.) are still the most economically valuable pollinators of monoculture crops cultivated globally, wild pollinator communities can contribute substantially toward crop pollination through pollination ecosystem services sourced from neighbouring natural habitats. Pollination ecosystem services are thus valuable and can motivate for the protection of natural ecosystems hosting diverse insect pollinator communities. F1 onion hybrid seed production is entirely dependent on high insect pollinator activity to ensure cross pollination, seed set and profitable seed yields. Data was collected on 18 onion hybrid seed crops grown in the semi‐arid Klein Karoo and southern Karoo regions of the Western Cape, South Africa. These two main production regions are located within the Succulent Karoo biome, recognized as a global biodiversity hotspot of especially high plant diversity. It is also habitat to the indigenous Cape honeybee (Apis mellifera capensis Esch.). Sites selected varied in the percentages of available natural habitat and managed honeybee hives stocking density. Diverse anthophile assemblages were sampled with pan traps within all the onion fields, regardless of the percentage of available natural habitat near the crop. Crop management practices significantly affected the diversity of anthophile species caught within onion fields, although less than 20% of this diversity was observed actually visiting onion flowers. The honeybee (managed and wild) was by far the most important pollinator because of its high visitation frequency and regular substantial onion pollen loads carried on their bodies. Honeybee visitation significantly increased onion hybrid seed yield, while anthophile diversity and non‐Apis visitation had no effect on seed yield. Neither managed hive density, nor percentage natural habitat were important in determining honeybee visitation or seed yield. Total annual rainfall was the only significant factor determining honeybee visitation. Secondary factors caused by rainfall variability, such as wild flower abundance or soil moisture, may have significantly affected honeybee visitation. In addition, the positive correlation between honeybee visitation and the diversity of hand‐sampled insects from onion flowers; indicate that either or both onion varietal attractiveness and/or pollinator population size may have had significant effects on overall insect visitation. Honeybees showed marked discrimination between hybrid onion parental lines and preferred to forage on one or the other during single foraging trips. Hybrid onion parents differed significantly in nectar characteristics and onion flower scent which would encourage selective foraging through floral constancy. Interspecies interactions were insignificant in causing increased honeybee pollination because of the scarcity of non‐Apis visitors. Most farming practices are subjected to favourable environmental conditions for successful production. However, and especially in the South African context, the dependence of onion hybrid seed crops on insect pollination for successful yields, increase its reliance on natural ecosystem dynamics that may deliver abundant wild honeybee pollinators, or attract them away from the crops. Nevertheless, this dependence can be mitigated effectively by the use of managed honeybee colonies to supplement wild honeybee workers on the flowers. / AFRIKAANSE OPSOMMING: Insek bestuiwing dra in verskillende grade by tot die produksie van landbou gewasse wat variteit en voedingswaarde in die mens se dieet verseker. Al is die heuningby (Apis mellifera L.) steeds die waardevolste ekonomiese bestuiwer van verboude enkelgewasse, kan wilde bestuiwers wesenlik bydra tot gewasbestuiwing deur middel van ekosisteem dienste afkomstig van natuurlike habitatte. Bestuiwing ekosisteem dienste is daarom waardevol en kan dus die bewaring van natuurlike ekosisteme, wat diverse gemeenskappe huisves, regverdig. F1 basterui saadproduksie is totaal afhanklik van hoë insek‐bestuiwer aktiwiteit om kruisbestuiwing, saadvorming en winsgewende saadopbrengste te verseker. Data is ingesamel op 18 basterui saad aanplantings in die half‐droë Klein Karoo en suid‐Karoo streke van die Weskaap, Suid‐Afrika. Hierdie twee hoof produksie streke is geleë binne die Sukkulente Karoo bioom wat erken word as ʼn globale biodiversiteits “hotspot” met hoë plant diversiteit. Dit is ook die habitat van die inheemse Kaapse heuningby (Apis mellifera capensis Esch.). Aanplantings is gekies om verskillende grade van beskikbare natuurlike habitat en bestuurde heuningby korf digthede te verteenwoordig. Diverse versamelings blom‐besoekers is versamel met water‐wippe in al die aanplantings, ongeag die persentasie natuurlike habitat beskikbaar by elke aanplanting. Gewas bestuurspraktyke het die diversiteit van blombesoekers betekenisvol beïnvloed. Tog is minder as 20% van hierdie diversiteit as aktiewe besoekers op die uiekoppe waargeneem. Heuningbye (bestuur of wild) was oorwegend die belangrikste bestuiwers as gevolg van hoë besoek frekwensies en wesenlike ladings uiestuifmeel op hulle liggame. Heuningby besoeke het saadopbrengs betekenisvol verhoog, maar blom‐besoeker diversiteit en nie‐Apis besoeke het geen effek op saadopbrengs gehad nie. Bestuurde korf digtheid en persentasie natuurlike habitat was nie belangrik in die bepaling van heuningby besoeke of basterui saadopbrengste nie. Totale jaarlikse reënval was die enigste betekenisvolle faktor wat heuningby besoeke bepaal het. Sekondêre faktore wat versoorsaak word deur reënval veranderlikheid, soos veldblom volopheid of grondvog, kon betekenisvolle effekte op die aantal heuningby besoeke gehad het. Bykomend, dui die positiewe korrelasie tussen heuningby besoeke en die diversiteit van hand‐versamelde insekte vanaf die uiekoppe op die moontlike betekenisvolle effek van elk of beide basterui variteit aantreklikheid en/of bestuiwer populasie grote op algehele insek besoeke. Heuningbye het noemenswaardige diskriminasie getoon tussen die basterui ouerlyne en het verkies om op een of die ander te wei tydens enkele weidingstogte. Basterui ouerlyne het betekenisvol verskil in nektar eienskappe en blomgeur wat die selektiewe weiding van heuningbye, toegepas deur blomkonstantheid, sal aanmoedig. Tussen‐spesie interaksies was onbetekenisvol in die verhoging van heuningby bestuiwing omdat nie‐Apis besoekers baie skaars was. Meeste boerdery praktyke is onderhewig aan gunstige omgewings toestande vir suksesvolle produksie. Maar, en veral in die Suid‐Afrikaanse konteks, omdat basterui saad aanplantings afhanklik is van insek bestuiwing vir suksesvolle opbrengste, word daar meer staat gemaak op natuurlike ekosisteem dinamika wat volop wilde heuningby bestuiwers kan voorsien, of selfs bestuiwers van die aanplanting kan weg lok. Nietemin, hierdie afhanklikheid kan effektief verlaag word deur die gebruik van bestuurde heuningby kolonies om die aantal wilde heuningby werkers op die blomme aan te vul.
147

Body Size and the Neural, Cognitive and Sensory Basis of Sociality in Bees

Riveros Rivera, Andre J. January 2009 (has links)
Body size is a universal property affecting biological structure and function, from cell metabolism to animal behavior. The nervous system, the physical generator of behavior, is also affected by variations in body size; hence potentially affecting the way animals perceive, interpret and react to the environment. When animals join to form groups, such individual differences become part of the structure of the society, even determining social roles. Here, I explore the association between body size, behavior and social organization in honeybees and bumblebees. Focusing on bumblebees, I explore the link between body size, brain allometry and learning and memory performance, within the context of task specialization. I show that body size goes along with brain size and with learning and memory performance, and that foraging experience affects such cognitive and neural features. Next, I explore the association between body size and foraging task specialization in honeybees. Previous evidence showed a link between specialization on pollen or nectar foraging and sensory sensitivity, further associating sensitivity to the quality and/or quantity of resource exploited. I hypothesize that, as in solitary bees, larger body size is associated with higher sensory sensitivity. I test this hypothesis by comparing body size and the quality and quantity of the resource exploited by wild Africanized and European honeybees. I show that nectar foragers are smaller and have fewer olfactory sensilla, which might underlie their lower sensitivity to odors. Also, larger bees collect more pollen (within pollen foragers) and more dilute nectar (within nectar foragers). To further test this `size hypothesis', I compare strains of bees selected to store large ("high strain") or small ("low strain") amounts of pollen surplus. As these strains differ in sensory sensitivity, I predict that the more sensitive high strain bees are larger and have more sensory sensilla. I show that high strain bees are generally bigger, but have fewer sensory sensilla than low strain bees. These results show that in bees, body size is associated with an individual's sensory, neural and cognitive features, further suggesting that body size plays a more important role in the organization of bee societies than generally assumed.
148

Allometric Scaling of Brain, Brain Components and Neurons with Body Size of Social Bees

Gowda, Vishwas, Gowda, Vishwas January 2016 (has links)
Animals in general vary immensely in body size, which greatly affects their morphology, physiology, survival, and nutritional requirements. The nervous system is also affected by variation in body size, which, in turn, shapes the perception of environmental stimuli and the behavior of animals. Comparative studies of vertebrates suggest that larger brains and their integrative centers comprise more and generally larger neurons (Jerison, 1973; Kaas, 2000), but much less is known about brain - body size relations in invertebrates. Closely related social bee species are well suited to study correlations between body size and brain composition. Different honey bee species vary in body size yet differ little in their ecological requirements and behavior and bumble bees feature a large range of body sizes even within a single colony.
149

Aspectos da biologia destinados à criação de Tetragona clavipes (Fabricius, 1804) (Apidae, Meliponini) / Biological aspects intended for beekeeping of Tetragona clavipes (Fabricius, 1804) (Apidae, Meliponini)

Duarte, Raoni da Silva 01 November 2012 (has links)
As abelhas sem ferrão eram criadas pelos Maias e indígenas da América do Sul. Desde então as técnicas evoluíram, surgindo vários modelos de caixas. No entanto alguns, na colheita, contaminam o mel e submergem os ovos no alimento larval. Na Amazônia surgiu um modelo mais vantajoso, utilizado por meliponicultores e pesquisadores. Das mais de 220 espécies de abelhas sem ferrão nativas do Brasil, criar um só modelo de caixa para todas não tem lógica. Tetragona clavipes, conhecida como borá, derivado de \'\'hebora\'\', que significa \'\'o que há de ter (mel)\'\', reserva grande quantidade de alimento, interessante para produção de mel. Portanto, pretendeu-se conhecer a arquitetura do ninho, o potencial de produção de mel, a preferência polínica e as propriedades antimicrobianas do mel e da própolis. O estudo foi realizado em Ribeirão Perto/SP, em vegetação urbana. Foram transferidas 18 colônias, a maioria de dentro de troncos. Nove sucumbiram, devido principalmente aos forídeos (Diptera, Phoridae). O volume médio dos ninhos de 10 colônias foi de 3994,8 cm³ e os favos de cria, de formato espiral, um diâmetro médio de 13,9 cm. De uma colônia foram calculadas as médias do peso da rainha (101,4 mg), largura dos favos de cria (11,1 cm), largura (5,98 mm) e altura (3,11 mm) das células de cria e células reais (8,5 mm; 6,1 mm, respectivamente), o número de células de cria por área de favo (10,9/cm²), altura dos pilares entre os favos (3,7 mm), altura e largura dos potes de mel (3,5 cm; 2,38 cm, respectivamente) e de pólen (3,71 cm; 2,33 cm, respectivamente), e volume de mel (6,55 ml) e peso do pólen (6,09 g) dentro de potes fechados. Um equipamento de ultrassom auxiliou a identificação de estruturas de ninhos dentro de troncos, porém nem todas. De oito enxames foram monitoradas as área de ocupação em caixa e o peso. Cinco morreram e o restante não cresceu, provavelmente devido ao frio. Não foi quantificada a produção de mel. De outra colônia foram coletadas abelhas regressantes com pólen, entre agosto de 2010 e julho de 2011. Foram identificados 45 tipos polínicos pertencentes a 17 famílias, além de sete não identificáveis. A família com mais tipos foi a Fabaceae e o coletado por maior período o tipo Amaranthus, gênero de uma planta comercial. Foram poucas plantas de relevância econômica, incluindo o tipo Citrus, entretanto, considerou-se possibilidades na polinização. Foram avaliadas as atividades antimicrobianas do mel e própolis frente à Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Paenibacillus larvae, Escherichia coli e Candida albicans. O mel não foi ativo contra E. coli. A própolis teve leve atividade contra S. aureus e S. epidermidis. Manejar e criar esta espécie de abelha requer cuidados. É necessário um modelo de caixa, que atenda às suas exigências. A diversidade polínica serviu para conhecer parte do recurso alimentar, e não, necessariamente, o potencial polinizador. O mel apresentou relevância na medicina e apicultura, mas a própolis teve atividade singela. Destacando o mel como alternativa contra micro-organismos resistentes. / The Mayas and the Indians of South America reared the stingless bees. Since then techniques have evolved, arising several hive models. However, in these, when harvesting, the honey is contaminated, and the eggs are submerged in larval food. In the Amazon, beekeepers and researchers use a more advantageous hive. With more than 220 species of stingless bees native in Brazil, creating a single hive model for all is not logical. Tetragona clavipes, known as borá, which comes from hebora, that means the one that has honey\', stores lots of food, interesting aspect for honey production. Therefore, we sought the knowledge about the nest architecture, the potential for honey production, pollen preference and the antimicrobial properties of honey and propolis. The study was conducted in Ribeirão Preto/SP in urban vegetation. Eighteen colonies were transferred, mostly from tree trunks. Nine died mainly due to phorid flies (Diptera, Phoridae). The average volume of the nest of 10 colonies was 3994.8 cm³ and combs, all with spiral format, had an average diameter of 13.9 cm. From one colony means were calculated such as, the weight of the queen (101.4 mg), width of the combs (11.1 cm), width (5.98 mm) and height (3.11 mm) of brood cells and royal cells (8.5 mm, 6.1 mm, respectively), the number of cells per area of comb (10.9/cm²), height of the pillars between the combs (3.7 mm), height and width of honey pots (3.5 cm and 2.38 cm, respectively) and pollen (3.71 cm and 2.33 cm, respectively) and the volume of honey (6.55 ml) and weight pollen (6.09 g) in closed pots. An ultrasonic apparatus assisted identification of structures of nests within trunks, but not all. Eight colonies were monitored the occupation inside the hives and the weight. Five died and the rest did not grow, probably due to the cold. The honey production was not quantified. From another colony were collected returning bees with pollen, between August 2010 and July 2011. Forty-five pollen types belonging to 17 families were identified, and seven were not possible to identify. The family Fabaceae had more types and the one collected for a longer period was type Amaranthus, genus of a commercial plant. Few plants of economic importance appered, including the type Citrus, however it was considered a few possibilities for pollination. The antimicrobial activity of honey, and propolis against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Paenibacillus larvae, Escherichia coli, and Candida albicans was evaluated. Honey was not active against E. coli. Propolis has mild antibacterial activity against S. aureus and S. epidermidis. Rearing this bee specie requires care. A hive model that meets its requirements is necessary. The pollen diversity served to know part of the food resource, and not necessarily the potential as a pollinator. Honey demonstrated its relevance in medicine and beekeeping, but propolis not as well. Highlighting, the honey seems to be an alternative against resistant micro-organisms.
150

Caracterização de méis monoflorais de eucalipto e laranja do Estado de São Paulo por técnicas termoanalíticas / Characterization of monoflorais eucalyptus and orange honeys from the State of São Paulo by thermoanalytical techniques

Maria Lurdes Felsner 06 December 2001 (has links)
Este trabalho apresenta o desenvolvimento e a otimização de metodologias analíticas para avaliação da temperatura de transição vítrea (Tg) por DSC e determinação do teor de umidade e cinzas por TG/DTG de amostras de mel. Além disso, foi realizado também um estudo da variabilidade nestes parâmetros físico-químicos e na temperatura de transição vítrea de amostras de méis monoflorais de eucalipto e laranja de algumas regiões do Estado de São Paulo. Para a avaliação termogravimétrica das amostras de mel, inicialmente foi realizado um estudo do comportamento térmico de padrões de carboidratos por TG/DTG, DSC e DTA Os resultados obtidos permitiram diferenciar as etapas de decomposição térmica correspondentes aos açúcares dos demais componentes presentes no mel. A variabilidade nos conteúdos de umidade e cinzas de méis de eucalipto e laranja foram investigadas por planejamento hierárquico e pela análise de variância (ANOVA) e verificou-se que estes parâmetros físico-químicos são significativamente diferentes no nível de 95% de confiança. Para o desenvolvimento e otimização de metodologias analíticas para a determinação do teor de umidade e de cinzas em mel por TG/DTG foram utilizados os métodos oficiais e aplicados planejamentos experimentais e um teste-F para a comparação entre variâncias. Os resultados sugeriram que para a obtenção de conteúdos médios de umidade e cinzas em mel por TG/DTG, similares aos encontrados pelos métodos oficiais, é necessário utilizar cadinho de alumina (150 &#181;L), taxas de aquecimento de 5ºC/min e papel de microfibra de vidro. Além disso, a comparação entre a variabilidade do método termogravimétrico com os métodos oficiais para estas determinações sugeriu que não existem diferenças significativas entre os métodos investigados. Para as amostras de méis monoflorais de laranja e eucalipto foram determinadas temperaturas de transição vítrea médias de -47 e -55ºC, respectivamente sugerindo uma diferença significativa nesta propriedade física para estes tipos de méis. Além disso, entre o conteúdo de umidade e a temperatura de transição vítrea destes tipos de méis foi verificada uma correlação linear negativa significativa no nível de 95% de confiança (r = - 0,916). Assim pode-se dizer, que os parâmetros fisico-químicos umidade e cinzas obtidos pelos métodos oficiais ou pelo método termogravimétrico e a temperatura de transição vítrea determinada por DSC podem ser utilizados para a caracterização da origem floral destes tipos de méis. / This work presents the optimization and development of analytical methodologies for evaluation of glass transition temperature (Tg) by DSC and for moisture and ash content determinations by TG/DTG of honey samples. Beyond this, a study of variability in these physicochemical parameters determined by conventional methods was realized for eucalyptus and citrus monofloral honeys of some regions of São Paulo State. For the thermogravimetric evaluation of honey samples, initially a study of thermal behavior of standard of carbohydrates was carried out by TG/DTG, DSC and DTA The results obtained allowed to distinguish the decomposition steps corresponding to the sugars in relation to other components present in honey. The variabilities in average moisture and ash contents of eucalyptus and citrus monofloral honeys were investigated by a hierarchical design and by an analysis of variance (ANOVA). These physicochemical parameters are significantly different at the 95% confidence level. For the development and optimization of analytical methodologies for moisture and ash contents in honey by TG/DTG conventional methods, experimental designs and a F-test for the comparison between variances were utilized. The results suggest that to get average moisture and ash contents in honey by TG/DTG similar to those found by conventional methods an alumine crucible (150 &#181;L ), heating rates of 5ºC/min and microfiber glass paper should be used. Besides this, the comparison between the thermogravimetric method and the conventional ones for these determinations suggest that there are no significant differences between the methods investigated. For eucalyptus and citrus monofloral honeys average glass transition temperatures of -47 and -55ºC, respectively, were determined suggesting a significant difference in this physical property for these honey types. Besides this, a significant negative linear correlation at 95% confidence level (r = - 0.916) was verified between the moisture contents and glass transition temperatures of these honey types. So, it may be said that the physicochemical parameters, moisture and ash, obtained by conventional and thermogravimetric methods and the glass transition temperature determined by DSC can be utilized for the characterization of the floral origin of these types of honey.

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