Browsing by Author "Almeida-Muradian, Ligia Bicudo"
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- Antimicrobial activity of dehydrated bee-pollen produced in four Brasilian States against microorganisms with clinical importancePublication . Almeida-Muradian, Ligia Bicudo; De-Melo, Adriane A.M.; Pereira, Ana Paula; Estevinho, Leticia M.The objective of this study was to determine the antimicrobial activity of eight dehydrated bee pollen samples collected from April to July 2012 in four Brazilian States: Sergipe Bahia; Rio Grande do Sul and São Paulo.
- Avaliação da qualidade nutricional e sanitária de amostras brasileiras de pólen apícolaPublication . Arruda, Vanilda Aparecida Soares de; Santos, Alexandre Vieria; Meira, David Figueiredo S.; Estevinho, Leticia M.; Almeida-Muradian, Ligia BicudoO pólen apícola tem sido utilizado na alimentação humana desde os primórdios da humanidade, devido à sua riqueza em proteínas, vitaminas, minerais e alguns tipos de hidratos de carbono. Contudo, se manipulado ou armazenado incorretamente pode perder o seu valor nutricional rapidamente.
- Brazilian bee pollen: phenolic content, antioxidant properties and antimicrobial activityPublication . Arruda, Vanilda Aparecida Soares de; Santos, Alexandre Vieria; Sampaio, Davi Figueiredo; Araújo, Elias da Silva; Peixoto, André Luís de Castro; Estevinho, Leticia M.; Almeida-Muradian, Ligia BicudoBee pollen has been promoted as a dietary supplement for humans due to its nutritional and bioactive properties. Sixty-two samples of Apis mellifera dehydrated bee pollen collected in Brazil (eight states and Federal District) were analyzed for phenolic compounds, flavonoids, antioxidant activity using DPPH, β-carotene and ORAC methods, and antimicrobial activity. The values obtained for total phenolic compounds ranged from 12.60 to 84.22 mg GAE/g bee pollen while total flavonoids oscillated between 1.90 and 36.85 mg quercetin/g bee pollen. The IC50 ranged from 0.35 to 13.42 mg bee pollen/mL of extract. The inhibition percentages ranged from 52.58 to 98.37% of bee pollen extract using the β-carotene method. When measured by the ORAC method, antioxidant activity was between 132.98 and 575.85 μmols eq. Trolox/g bee pollen. Bee pollen efficiently inhibited the growth of all the microorganisms studied. Candida albicans was the most resistant, while Staphylococcus epidermides was the most sensitive.
- Brazilian samples of bee samples pollen: palynological origin, phenolic content, antioxidant properties and antimicrobial activityPublication . Arruda, Vanilda Aparecida Soares de; Santos, Alexandre Vieria; Figueiredo, Davi; Meira, Sampaio; Estevinho, Leticia M.; Barth, Ortrud M.; Freitas, Alex da Silva; Almeida-Muradian, Ligia BicudoTotal phenolic and flavonoids phytochemical concentration was measured in bee pollen samples, Appis Mellifera , as well as their botanical origin, antioxidant activity and antimicrobial activity. Pollen loads were washed with 70% ethanol and identified using a 400x magnification. The content of total polyphenols and flavonoids was measured spectrophotometrically with gallic acid and quercetin as standard. The antioxidant activity was evaluated by the linking capacity of (i)the free radical DPPH (2,2-Diphenyl-1-picrylhydrazyl), (ii)ORAC and (iii)system β-carotene/linoleic acid. The experiments were performed in triplicate and the results expressed as mean ± standard deviation. All statistical analysis were performed using the program STATISTICA 8.0 and adopting the significance level of 5% (p<0.05). Were using six samples of dehydrated bee pollen collected in Ribeirao Preto, SP, Brazil during the years of 2010 and 2011. Five families were found in the mixture of bee pollen: Mimosa caesalpiniaefolia , Mimosa scabrella, Asteraceae, Poaceae, Zea mays. Each dried bee pollen sample was composed mainly of Mimosa caesalpiniaefolia (Fabaceae-Mimosoideae). The variations were (dry basis): 17.64±1.57 to 32.14±2,88 mg GAE/g of bee pollen for phenolic compounds; 2.51±0.28 to 3.71±0.25 mg quercetin/g of pollen for flavonoids concentration; 77.15±0.72 to 90.56% for antioxidant activity (DPPH) and 3.19±0.25 to 4.61±0.33 mg/mL for EC50; 183.42±16.26 to 338.32± 33.38 μmols eq. Trolox/g for ORAC and 68.96±2.75 to 85.90±2.27% for β -carotene/linoleic acid. Samples of pollen, phenolics and flavonoids have the potential biological, showing high antioxidant activity by the three methods used. It was verified that the presence of pollen differentially affected the growth of bacteria Gram-positive, Gram-negative and yeasts under study, depending this on the microorganism and the pollen used in fact, only one after sample was monofloral Mimosa caesalpiniaefolia. This is an important study since; their characterization can increase their economic value. The opinions, hypothesis and conclusions or recommendations expressed in the article are those of the authors and do not necessarily coincide with those of FAPESP.
- Comparative study of the physicochemical and palynological characteristics of honey from Melipona subnitida and Apis melliferaPublication . Almeida-Muradian, Ligia Bicudo; Stramm, Klaus Martin; Horita, Andreia; Barth, Ortrud M.; Freitas, Alex da Silva; Estevinho, Leticia M.Twenty-four samples of Apis mellifera honey and twenty-four samples of Melipona subnitida (Jandaira) honey were collected in the northeast of Brazil. Moisture, hydroxymethylfurfural, free acidity, insoluble solids in water, diastase activity, ashes, electrical conductivity, proteins, lipids, total carbohydrates, energy and sugars were the parameters analysed. The efficiency of the qualitative tests (Fiehe’s test, Lugol’s reaction, Lund’s reaction) was tested. Pollen types and the corresponding plant species were identified in all samples (3 in Apis and 1 in Melipona). Apis mellifera honey samples demonstrated parameters in accordance with the Brazilian Legislation, while the Melipona subnitida honey samples displayed moisture (24.80%) and diastase activity (null) in discordance with the established by the regulation for Apis mellifera honeys. Apis honey samples presented higher values of electric conductivity (284.00 lS cm 1) than the obtained from the Jandaira honey samples (102.77 lS cm 1) as well as a darker colour (26.67 mmPfund) when compared with Jandaira honey (7.00 mmPfund). The concentration of the glucose, fructose and sucrose was higher in the Apis honeys than in the Jandaira honey. The characteristics of the two types of honey were very different, highlighting the need of developing specific legislation for stingless bees’ honey.
- A diagnosis of the microbiological quality of dehydrated bee-pollen produced in BrazilPublication . De-Melo, Adriane A.M.; Estevinho, Leticia M.; Almeida-Muradian, Ligia BicudoBee-pollen is an apicultural product with potential for medical and nutritional applications; therefore, its microbiology quality should be monitored. In this context, the objective of this study was to diagnose the microbiological quality of 45 dehydrated bee-pollen samples collected from November 2011 to December 2013 in nine Brazilian States. All the samples were negative for sulphite-reducing Clostridium spores, Salmonella, coagulase-positive Staphylococcus and Escherichia coli, which are micro-organisms of public health concern. Total aerobic mesophilic micro-organism counts ranged from < 10 to 1·10 × 10 4 CFU g -1 , with psychrotroph counts ranging from < 10 to 1·12 × 10 3 CFU g -1 and total coliforms from < 10 to 2·80 × 10 3 CFU g -1 , while the values for yeasts and moulds were between < 10 to 7·67 × 10 3 CFU g -1 . According to the literature, the microbiota observed in this study were typical; however, it is important to consider that these micro-organisms may cause spoilage and diminish shelf life, reason by which quality control programs should be implemented. Significance and Impact of the Study: Contamination of bee-pollen can occur during production, collection and processing, but there are few studies of the microbiological quality of this product. Brazil is an important producer of dehydrated bee-pollen, therefore, a diagnosis of the microbiological status is important to ensure the safety of many consumers. Salmonella sp., genus Clostridium, coagulase-positive Staphylococcus, Escherichia coli and even some yeast species are micro-organisms of public health concern and their presence must be monitored. Furthermore, the determination of spoilage micro-organisms indicates whether the production and the processing practices carried out by beekeepers and warehouses were adequate. Significance and Impact of the Study: Contamination of bee-pollen can occur during production, collection and processing, but there are few studies of the microbiological quality of this product. Brazil is an important producer of dehydrated bee-pollen, therefore, a diagnosis of the microbiological status is important to ensure the safety of many consumers. Salmonella sp., genus Clostridium, coagulase-positive Staphylococcus, Escherichia coli and even some yeast species are micro-organisms of public health concern and their presence must be monitored. Furthermore, the determination of spoilage micro-organisms indicates whether the production and the processing practices carried out by beekeepers and warehouses were adequate.
- Efect of Gamma irradiation on the microbiological quality of dehydrated bee-pollenPublication . De-Melo, Adriane A.M.; Estevinho, Leticia M.; Almeida-Muradian, Ligia BicudoThe objective of this study was to determinate some microbiological parameters of seven dehydrated bee-pollen collected from September to December of2012, in Brazil, before and after irradiation, in order to observe if the conservation process influenced the final microbiological load. All bee-pollen samples were collected in the same apiary and processed as usual; then one parcel of each one was gamma-irradiated to achieve dose of 5.0 kGy with a cobalt-60 source (by EMBRARAD/Empresa Brasileira de Radia~aes Ltda, Cotia, SAo Paulo, Brasil). The bee-pollen samples were analysed to enumerate aerobic mesophilic and psychotrophs bacteria, Staphylococcus aureus, total coliforms and yeasts and molds and to determine the presence or absent of sulphite-reducing Clostridium spores and Salmonella. Each sample ( 10 g) was homogenised and serial dilutions were inoculated on specific medium. Afterwards, incubations were performed depending on the microorganism (Estevinho et al., 2012). Results were expressed as colonyforming units per gram of dehydrated bee-pollen (CFU.g-1) for mesophilic, psychotrophs, Staphylococcus aureus, total coliforms and yeasts and molds or as presence or absent for sulphite-reducing Clostridium spores and Salmonella.
- Effect of processing conditions on characteristics of dehydrated bee-pollen and correlation between quality parametersPublication . De-Melo, Adriane A.M.; Estevinho, Leticia M.; Sattler, José Augusto Gasparotto; Souza, Bianca Rodrigues; Freitas, Alex da Silva; Barth, Ortrud M.; Almeida-Muradian, Ligia BicudoThe aim of the present study was to compare the physical, chemical and biological parameters and the microbiological quality of bee-pollen samples treated with different dehydration processes and to correlate the results. The samples came mainly from Eucalyptus (Myrtaceae) and Eupatorium (Asteraceae) plants. The dehydration conditions of the samples influenced the L*a*b* colour parameters and the biological value. Unlike the protein and lipid content, the glucose and fructose content were unaffected. The vitamin E content (27.2 ± 0.3 μg/g, 27.5 ± 0.4 μg/g) in oven-dehydrated samples with forced air circulation was significantly lower (P < 0.05) compared with lyophilized samples (37.5 ± 0.2 g/100 g, 53.7 ± 3.9 g/100 g). Overall, the results were inconclusive for vitamin B complex, minerals and microbiological indicators. There was a positive correlation between the colour parameters L* and b* and the total phenolic content, as well as between phenolic content and the antioxidant and antimicrobial capacity. The data indicate that lyophilization might be a viable alternative to the current process, resulting in dehydrated bee-pollen with higher biological activity.
- Efficiency of the FT-IR ATR spectrometry for the prediction of the physicochemical characteristics of Melipona subnitida honey and study of the temperature’s effect on those propertiesPublication . Almeida-Muradian, Ligia Bicudo; Stramm, Klaus Martin; Estevinho, Leticia M.The efficiency of ATR FT-IR spectrometry was compared with recommended methodologies for physicochemical parameters of eighteen samples of Melipona subnitida honey. Significant differences were found between the values obtained using those techniques for hydroxymethylfurfural, ash and electrical conductivity. The results for the other parameters did not differ significantly, suggesting that this rapid and nondestructive methodology may predict parameters usually used to assess honeys’ quality. The effects of different storage conditions (room temperature, fridge and freezer) on the quality parameters of the product stored during 12 months were studied. Darkening of the honey was observed, particularly in the fridge and freezer. However, the changes occurring in the honey kept on the fridge were not statistically different from those occurring in the product kept on the freezer, except for free acidity. The results obtained for the honey stored at room temperature, best way to preserve, differed significantly from those obtained for the honey kept under the other conditions.
- HPLC- MS Flavonoid determination and antioxidant capacity of Brazilian dehydrated bee pollenPublication . De-Melo, Adriane A.M.; Estevinho, Leticia M.; Moreira, Manuela M.; Delerue-Matos, Cristina; Almeida-Muradian, Ligia BicudoBee-pollen, produced by Apis mellifera bees, is an important source of proteins, lipids, vitamins and minerals for the hive, being considered one of nature's most completely nourishing foods. Its composition may vary according to the geographical region and its quality is influenced by harvest method and processing conditions. Although it has good nutritional components, beepollen contains significant amounts of polyphenols with recognized health benefits, including antioxidant activity. The present study aimed to evaluate the flavonoid composition, using HPLC-MS technique; and the antioxidant activity, using two different methods (DPPH and ORAC), of eight dehydrated bee-pollen samples collected in different Brazilian apiaries. The sample with the highest antioxidant capacity using DPPH method was produced in Rio Grande do Sul State (110.85 mol TE/g) while the sample with the least antioxidant capacity was collected in Bahia State (9.97 mol TE/g). The same sample from Rio Grande do Sul State presented the highest antioxidant capacity using ORAC method (542.00 mol TE/g), while the lowest value was observed in a sample from Mato Grosso State (133.70 mol TE/g). The flavonoid analysis using HPLC-MS revealed the following variations: catechin (0.69 to 0.75 mg/100 g); naringenine (4.57 to 18.36 mg/100 g); rutin (3.36 to 46.80 mg/100 g); quercetin (1.86 to 67.91 mg/100 g) and kaempferol (5.50 to 44.97 mg/100 g). In the sample with the highest antioxidant capacity (Rio Grande do Sul State) was observed 40 peaks in the HPLC-MS, while the samples with the lowest antioxidant capacities the number of peaks were 25 (Mato Grosso State) and 22 (Bahia State); therefore, the variety of compounds may have influenced the antioxidant capacity of the samples.
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