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1.
Microorganisms ; 11(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38004790

RESUMO

Geopropolis has been used in traditional medicine for centuries. In this study, the botanical origin, physicochemical profile, and biological activities of geopropolis from Melipona scutellaris harvested during rainy and dry seasons were investigated. Palynological analysis identified over 50 pollen types, with Schinus terebinthifolius and Cecropia being the predominant types. The analytical results were in line with those reported in the literature. Rainy-season geopropolis exhibited higher total phenol and flavonoid content (determined using High Performance Liquid Chromatography-25.13% and 3.92%, respectively) compared to the dry season (19.30% and 2.09%); the major peaks (naringin, gallic acid, and catechin) were similar among samples. Antioxidant capacity was assessed via DPPH, reducing power, and ß-carotene/linoleic acid discoloration assays. Rainy-season samples displayed superior antioxidant activity across methods. Antimicrobial effects were determined using microdilution, while the impact on the cholinesterase enzyme was quantified using 5-thio-2-nitrobenzoic acid accumulation. Anti-inflammatory and antimutagenic activities were assessed through hyaluronidase enzyme inhibition and by utilizing Saccharomyces cerevisiae ATCC-20113 cells. Both samples exhibited anti-inflammatory and antimutagenic properties. Moreover, a significant inhibition of acetylcholinesterase was observed, with IC50 values of 0.35 µg/mL during the rainy season and 0.28 µg/mL during the dry season. Additionally, the geopropolis displayed antimicrobial activity, particularly against Staphylococcus aureus. These findings suggest the therapeutic potential of M. scutellaris geopropolis in the context of inflammatory, oxidative, and infectious diseases.

2.
Food Res Int ; 170: 112964, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316052

RESUMO

Bee Pollen is a valuable and useful natural food product that can be used for different purposes, among which medical ones. This matrix is deemed a superfood because of its chemical composition, which is rich in nutrients and possesses significant bioactivities, including antioxidant and microbiological properties. Nevertheless, the storage conditions and processing methods must be optimized to maintain their properties and maximise their application. This work investigates the best bee pollen conservation process and its impact on individual constituents. Monofloral bee pollen was analysed for 30 and 60 days after three different storage processes (drying, pasteurization, and high-pressure pasteurization). The results showed a decrease mainly in fatty acid and amino acid content for the dried samples. The best results were obtained with high-pressure pasteurization, maintaining the proteins, amino acids and lipids characteristics of pollen and the lowest microbial contamination.


Assuntos
Dessecação , Pasteurização , Abelhas , Animais , Aminoácidos , Antioxidantes , Pólen
3.
Environ Sci Pollut Res Int ; 28(1): 503-517, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32815014

RESUMO

Natural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities of Euphorbia resinifera and Euphorbia officinarum aqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected in E. officinarum honey, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared with E. resinifera honey, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 - 2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.


Assuntos
Euphorbia , Mel , Antioxidantes , Mel/análise , Marrocos , Fenóis/análise , Extratos Vegetais
5.
Molecules ; 24(12)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248102

RESUMO

A marked decrease in human cancers, including breast cancer, bone cancer, and cervical cancer, has been linked to the consumption of vegetable and fruit, and the corresponding chemoprotective effect has been associated with the presence of several active molecules, such as kaempferol. Kaempferol is a major flavonoid aglycone found in many natural products, such as beans, bee pollen, broccoli, cabbage, capers, cauliflower, chia seeds, chives, cumin, moringa leaves, endive, fennel, and garlic. Kaempferol displays several pharmacological properties, among them antimicrobial, anti-inflammatory, antioxidant, antitumor, cardioprotective, neuroprotective, and antidiabetic activities, and is being applied in cancer chemotherapy. Specifically, kaempferol-rich food has been linked to a decrease in the risk of developing some types of cancers, including skin, liver, and colon. The mechanisms of action include apoptosis, cell cycle arrest at the G2/M phase, downregulation of epithelial-mesenchymal transition (EMT)-related markers, and phosphoinositide 3-kinase/protein kinase B signaling pathways. In this sense, this article reviews data from experimental studies that investigated the links between kaempferol and kaempferol-rich food intake and cancer prevention. Even though growing evidence supports the use of kaempferol for cancer prevention, further preclinical and clinical investigations using kaempferol or kaempferol-rich foods are of pivotal importance before any public health recommendation or formulation using kaempferol.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Quempferóis/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Antioxidantes/química , Antioxidantes/farmacocinética , Antioxidantes/farmacologia , Quimioprevenção , Avaliação Pré-Clínica de Medicamentos , Humanos , Quempferóis/química , Quempferóis/farmacocinética , Redes e Vias Metabólicas
6.
Molecules ; 24(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30986961

RESUMO

Ligustrum lucidum Aiton and its berries have been used in Chinese traditional medicine for around two thousand years. In the present study, L. lucidium berries harvested in two regions of Portugal were studied. Haemolytic activity and inhibition of oxidative haemolysis as well as the enzyme inhibitory activities (α-amylase enzyme and acetylcholinesterase) were assessed. Results suggest that the different biological activities varied according to the region where samples were collected. Results demonstrated that the sample obtained from region R1 was the most efficient extract for all parameters evaluated, presenting the lowest values of IC50, 10.67 ± 0.46 µg/mL for the inhibition of erythrocyte oxidative haemolysis, 58.28 ± 3.77 µg/mL for the α-amylase enzyme and 67.67 ± 2.10 µg/mL for the acetylcholinesterase inhibition. L. Lucidum berries may be an interesting source of compounds for use in the development of the therapeutic armamentarium for diseases where enzymatic disruption is believed to play a role.


Assuntos
Frutas/química , Ligustrum/química , Extratos Vegetais/farmacologia , Acetilcolinesterase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Extratos Vegetais/química , alfa-Amilases/metabolismo
7.
J Agric Food Chem ; 67(2): 688-698, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30575387

RESUMO

This study assessed 16 different honey samples in order to select the best one for therapeutic purposes. First, a study of honey's main bioactive compounds was carried out. Then phenolic profiles were determined and specific compounds quantified using a HPLC system coupled to a mass spectrometer. Then, antioxidant activity, by three in vitro methods, and antibacterial activity against reference strains and clinical isolates were evaluated. Great variability among samples was observed regarding ascorbic acid (between 0.34 ± 0.00 and 75.8 ± 0.41 mg/100 g honey; p < 0.001), total phenolic compounds (between 23.1 ± 0.83 and 158 ± 5.37 mg/100 g honey; p < 0.001), and total flavonoid contents (between 1.65 ± 0.11 and 5.93 ± 0.21 mg/100 g honey; p < 0.001). Forty-nine different phenolic compounds were detected, but only 46 of them were quantified by HPLC. The concentration of phenolic compounds and the phenolic profiles varied widely among samples (between 1.06 ± 0.04 and 18.6 ± 0.73 mg/100 g honey; p < 0.001). Antioxidant activity also varied significantly among the samples. All honey varieties exhibited antibacterial activity against both reference and clinical strains (effective concentrations ranged between 0.05 and 0.40 g/mL depending on the honey sample and bacteria tested). Overall, samples with better combinations of bioactive properties were avocado and chestnut honeys.


Assuntos
Antibacterianos/química , Antioxidantes/química , Mel/análise , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ácido Ascórbico/análise , Ácido Ascórbico/farmacologia , Bactérias/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/farmacologia , Mel/classificação , Espectrometria de Massas , Fenóis/química , Fenóis/farmacologia
8.
Oxid Med Cell Longev ; 2018: 2976985, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050651

RESUMO

Hancornia speciosa Gomes is a fruit tree, commonly known as the mangaba tree, which is widespread throughout Brazil. The leaves of this plant are used in traditional medicine for medicinal purposes. Thus, the objective of this study was to perform a physicochemical characterization, identify the lipophilic antioxidants and fatty acids, and determine the microbiological quality and safety of H. speciosa leaves. In addition, the antioxidant, antimutagenic, and inhibitory activities of the ethanolic extract of H. speciosa leaves (EEHS) against enzymes related to neurodegenerative diseases, inflammation, obesity, and diabetes were investigated. Furthermore, this study aimed at assessing the in vivo effects of the EEHS on the glycemia of normoglycemic and diabetic Wistar rats. Physicochemical characterization was performed by colorimetry and gas-liquid chromatography with flame ionization detection (GC-FID). The total number of colonies of aerobic mesophiles, molds, and yeasts was determined. The total coliforms and Escherichia coli were counted using the SimPlates kit, and sulphite-reducing Clostridium spores were quantified using the sulphite-polymyxin-sulfadiazine agar method. Salmonella spp. were detected using the 1-2 Test. The antioxidant activity of the EEHS was measured by its inhibition of 2,2'-azobis(2-amidinopropane) dihydrochloride- (AAPH-) induced oxidative hemolysis of human erythrocytes. The antimutagenic activity was determined using the Ames test. The acetylcholinesterase, butyrylcholinesterase, tyrosinase, hyaluronidase, lipase, α-amylase, and α-glycosidase enzyme-inhibiting activities were assessed and compared with commercial controls. The in vivo effects of the EEHS were assessed using the oral glucose tolerance test in normoglycemic Wistar rats and measuring the blood glucose levels in diabetic rats. The results demonstrated physical-chemical parameters of microbiological quality and safety in the leaves of H. speciosa, as well as antioxidant and antimutagenic activities and inhibition of enzymes related to neurodegenerative diseases, inflammation, obesity, and diabetes. In in vivo assays, it was shown that the normoglycemic rats challenged with glucose overload show significantly decreased blood glucose levels when treated with the EEHS. Taken together, the results ensure the microbiological quality and safety as well as showing the contents of carotenoids and polyunsaturated fatty acids of H. speciosa leaves. Additionally, the antioxidant, antimutagenic, anti-inflammatory, anti-Alzheimer's disease, anti-Parkinson's disease, antiobesity, and antihyperglycemic activities of the EEHS were demonstrated.


Assuntos
Apocynaceae/química , Extratos Vegetais/farmacologia , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Butirilcolinesterase/metabolismo , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Frutas/química , Humanos , Hialuronoglucosaminidase/metabolismo , Masculino , Extratos Vegetais/efeitos adversos , Ratos , Ratos Wistar
9.
Food Chem ; 267: 36-42, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934179

RESUMO

The aim of this work was to develop computational intelligence models based on neural networks (NN), fuzzy models (FM), and support vector machines (SVM) to predict physicochemical composition of bee pollen mixture given their botanical origin. To obtain the predominant plant genus of pollen (was the output variable), based on physicochemical composition (were the input variables of the predictive model), prediction models were learned from data. For the inverse case study, input/output variables were swapped. The probabilistic NN prediction model obtained 98.4% of correct classification of the predominant plant genus of pollen. To obtain the secondary and tertiary plant genus of pollen, the results present a lower accuracy. To predict the physicochemical characteristic of a mixture of bee pollen, given their botanical origin, fuzzy models proven the best results with small prediction errors, and variability lower than 10%.


Assuntos
Redes Neurais de Computação , Pólen/química , Animais , Abelhas , Plantas/genética , Pólen/classificação , Pólen/genética , Máquina de Vetores de Suporte
11.
PLoS One ; 11(12): e0167531, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27907185

RESUMO

Hancornia speciosa Gomes (Apocynaceae) is a fruit tree, popularly known as mangabeira, and it is widely distributed throughout Brazil. Several parts of the plant are used in folk medicine, and the leaf and bark extracts have anti-inflammatory, antihypertensive, antidiabetic, and antimicrobial properties. In this study, we investigated the chemical composition of the ethanolic extract of Hancornia speciosa leaves (EEHS) and its antioxidant, antimicrobial, and cytotoxic activities as well as the mechanisms involved in cell death. The chemical compounds were identified by liquid chromatography coupled to mass spectrometry (LC-MS/MS). The antioxidant activity of the EEHS was investigated using the method that involves the scavenging of 2,2-diphenyl-1-picrylhydrazyl free radicals as well as the inhibition of oxidative hemolysis and lipid peroxidation induced by 2,2'-azobis (2-amidinopropane) in human erythrocytes. The antimicrobial activity was determined by calculating the minimum inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration, and zone of inhibition. Kasumi-1 leukemic cells were used to assess the cytotoxic activity and mechanisms involved in cell death promoted by the EEHS. The chemical compounds identified were quinic acid, chlorogenic acid, catechin, rutin, isoquercitrin, kaempferol-rutinoside, and catechin-pentoside. The EEHS demonstrated antioxidant activity via the sequestration of free radicals, inhibition of hemolysis, and inhibition of lipid peroxidation in human erythrocytes incubated with an oxidizing agent. The antimicrobial activity was observed against American Type Culture Collection (ATCC) and hospital strains of bacteria and fungi, filamentous fungi and dermatophytes. The cytotoxic activity of the EEHS was induced by apoptosis, reduction of the mitochondrial membrane potential, and activation of cathepsins. Together, these results indicate the presence of phenolic compounds and flavonoids in the EEHS and that their antioxidant, antimicrobial, and cytotoxic activities in acute myeloid leukemia cells are mediated by apoptosis.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Apocynaceae/química , Citotoxinas/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Anti-Infecciosos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Catequina/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácido Clorogênico/isolamento & purificação , Citotoxinas/isolamento & purificação , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Hemólise/efeitos dos fármacos , Humanos , Quempferóis/isolamento & purificação , Testes de Sensibilidade Microbiana , Fenóis/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Ácido Quínico/isolamento & purificação , Rutina/isolamento & purificação
12.
Oxid Med Cell Longev ; 2016: 8405957, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27803764

RESUMO

Natural products can be a source of biomolecules with antioxidant activity which are able to prevent oxidative stress-induced diseases and show antitumor activity, making them important sources of new anticancer drug prototypes. In this context, this study aimed to analyze the chemical composition of an ethanol extract of Senna velutina leaves and to assess its antioxidant and cytotoxic activities in leukemic cells. The antioxidant properties were evaluated using a DPPH free radical scavenging assay and by examining the extract's inhibition of AAPH-induced lipid peroxidation in human erythrocytes. Its cytotoxicity and possible mechanisms of action were assessed in Jurkat and K562 leukemic cell lines. The ethanol extract contained flavonoids, such as epigallocatechin, epicatechin, kaempferol heteroside, rutin, and dimeric and trimeric proanthocyanidin derivatives. The extract exhibited antioxidant activity by scavenging free radicals and antihemolytic action, and it decreased malondialdehyde content in human erythrocytes. Furthermore, the extract also induced leukemic cell death by activating intracellular calcium and caspase-3, decreasing mitochondrial membrane potential, and arresting the cell cycle in S and G2 phases. Hence, S. velutina leaf extract contains antioxidant and antileukemic biomolecules with potential applications in diseases associated with oxidative stress and in the inhibition of tumor cell proliferation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Leucemia/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Senna/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Cálcio/metabolismo , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Células Jurkat , Células K562 , Leucemia/metabolismo , Leucemia/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Fitoterapia , Picratos/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos
13.
Molecules ; 20(7): 12525-44, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26184138

RESUMO

This study aims to assess the microbiological parameters and the chemical composition of 21 samples of stingless bee pollen (Melipona mandacaia) from two regions of Bahia, Brazil (João Dourado and Uibaí), with particular emphasis on the nutritional value, total phenols and flavonoids and fatty acids composition. Regarding the microbiological quality, the studied microorganisms (moulds and yeasts, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella sp., psychrotrophic and sulfite-reducing Clostridia) were absent in all samples. On the other hand, the values obtained for the aerobic mesophilic microorganism ranged from 11.0 ± 1.0 to 1.32 ± 1.2 cfu∙g-1 (JD samples) and from 282 ± 3.82 to 688 ± 10.1 cfu∙g-1 (U samples). The nutritional parameters (moisture, ash, water activity, pH, total acidity, protein, fiber, total phenolic, flavonoids and reducing sugars) were within the stipulated by law, except for pH and moisture content, which presented superior and inferior values, respectively. Polyunsaturated fatty acids (54.1%) were significantly higher than saturated (42.18%) and monounsaturated (3.71%). It was found that the bee pollen is safe from the microbiological point of view and has a good nutritional quality. The influence of the geographical origin on the assessed parameters was evident, especially concerning the fatty acid profile.


Assuntos
Abelhas/fisiologia , Ácidos Graxos/isolamento & purificação , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Pólen/química , Animais , Bactérias Aeróbias/isolamento & purificação , Contagem de Colônia Microbiana , Fibras na Dieta/análise , Proteínas Alimentares/análise , Ácidos Graxos/química , Ácidos Graxos/classificação , Flavonoides/química , Flavonoides/classificação , Concentração de Íons de Hidrogênio , Fenóis/química , Fenóis/classificação , Pólen/microbiologia , Água/análise
14.
Food Chem Toxicol ; 63: 233-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24262487

RESUMO

Bee pollen is considered, since memorable times, a good source of nourishing substances and energy. The present study aimed to evaluate the biological activities of eight commercial bee pollens purchased from the market. The origin of sample A was not specified in the labeling; samples B, C, D and G were from Portugal and the remaining were from Spain. The sample E presented the highest value of phenolics (32.15±2.12 mg/g) and the H the lowest (18.55±095 mg/g). Sample C had the highest value of flavonoids (10.14±1.57 mg/g) and sample H the lowest (3.92±0.68 mg/g). All the samples exhibited antimicrobial activity, being Staphylococcus aureus the most sensitive and Candida glabrata the most resistant of the microorganisms studied. All the samples exhibited antimutagenic activity, even though some samples were more effective in decreasing the number of gene conversion colonies and mutant colonies. Regarding the antioxidant activity, assessed using two methods, the more effective was sample B. The anti-inflammatory activity, assessed using the hyaluronidase enzyme, was highest in samples B and D. Pearson's correlation coefficients between polyphenols, flavonoids, antioxidant activity and antimicrobial activity were computed. It was also performed a discriminant analysis.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Abelhas , Pólen , Animais , Análise Discriminante , Testes de Sensibilidade Microbiana
15.
Molecules ; 18(4): 4573-87, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23599015

RESUMO

Virgin oils obtained from seeds of Camellia oleifera (CO), Camellia reticulata (CR) and Camellia sasanqua (CS) were studied for their triacylglyceride composition, antioxidant and antimicrobial activities. Levels of fatty acids determined by ¹H-nuclear magnetic resonance analysis were similar to those reported for olive oils (82.30%-84.47%; 5.69%-7.78%; 0.26%-0.41% and 8.04%-11.2%, for oleic, linoleic, linolenic and saturated acids, respectively). The CR oil showed the best antioxidant potential in the three in vitro models tested. With regard to EC50 values (µg/mL), the order in DPPH radical-scavenging was CR (33.48) < CO (35.20) < CS (54.87). Effectiveness in reducing power was CR (2.81) < CO (3.09) < CS (5.32). IC50 for LPO inhibition were 0.37, 0.52 and 0.75 µg/mL for CR, CO and CS, respectively. All the oils showed antimicrobial activity, and exhibited different selectivity and MICs for each microorganism tested (E. coli, B. cereus and C. albicans). B. cereus was the less sensitive species (MIC: 52.083 ± 18.042 for CO; 41.667 ± 18.042 for CR; 104.167 ± 36.084 for CS mg/mL) and the E. coli was the most sensitive to camellia oil's effect. The standard gentamicin presented higher MIC for E. coli (4.2) than the CR (MIC= 2.6) and CO (MIC = 3.9) oils.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Camellia/química , Óleos de Plantas/química , Triglicerídeos/farmacologia , Anti-Infecciosos/química , Antioxidantes/química , Ácidos Graxos/química , Concentração Inibidora 50 , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ressonância Magnética Nuclear Biomolecular , Oxirredução/efeitos dos fármacos , Triglicerídeos/química
16.
Molecules ; 18(4): 4233-46, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23579991

RESUMO

This study aimed to determine the factors (phenolic compounds, flavonoids, sugars or H2O2) that contribute the most to the antimicrobial activity of heather honey samples against four yeasts and four bacteria with medical importance. To discard the effect of H2O2 in the antimicrobial activity, catalase was added. To evaluate the osmotic pressure's effect, artificial honey was also used. Phenolic compounds and flavonoids were determined and Pearson's correlation analysis was performed to assess whether these correlated with antimicrobial activity. The amount of phenolic compounds ranged from 630.89 ± 5.21 GAE kg-1 to 718.92 ± 4.41 GAE kg-1, while the flavonoids varied between 450.72 ± 5.67 CAE kg-1 and 673.98 ± 4.33 CAE kg-1. For the bacteria, the minimum inhibitory concentration (MIC) of the honey without catalase ranged from 1.01 ± 0.50% to 10.00 ± 4.72% and was between 2.00 ± 0.94% and 13.27 ± 5.23% for honey with catalase. Concerning the yeasts, the MICs was between 13.16 ± 4.08% and 20.00 ± 5.09% for honey without catalase and between 14.95 ± 4.16% and 25.67 ± 5.50% for honey with catalase. The elucidation of the antimicrobial factors and action mechanisms is essential for the correct use of honey in therapeutic applications.


Assuntos
Ericaceae/química , Mel/análise , Extratos Vegetais/farmacologia , Anti-Infecciosos/farmacologia , Catalase/análise , Catalase/metabolismo , Flavonoides/farmacologia , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Peróxido de Hidrogênio/farmacologia , Testes de Sensibilidade Microbiana , Fenóis/farmacologia
17.
Food Chem Toxicol ; 51: 143-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23022013

RESUMO

This study has the objective of evaluating the stability of B complex vitamins and its vitamers, for a period of 1year of storage. The pollen samples were stored under room temperature (with and without light) and frozen. The vitamins were quantified by HPLC with fluorescence detection. All proposed vitamins were found in the samples and the dehydration process did not interfere in vitamin content. The variations were (dry basis): 0.59-1.09mg/100g (B(1)); 1.73-2.56 (B(2)); 6.43-15.34 (PP) and 0.33-0.68 (B(6)). After 1year of storage, it can be stated that vitamin B(1) concentration remained constant, while for the others, the concentration loss was dependent on time rather than on storage conditions. All samples were considered vitamin B(2) sources. The influence of the storage time in the concentrations of vitamin B(6) and PP was explained mathematically, through linear regression equations of multivariate analysis.


Assuntos
Abelhas , Armazenamento de Alimentos/métodos , Pólen/química , Complexo Vitamínico B/análise , Complexo Vitamínico B/química , Animais , Cromatografia Líquida de Alta Pressão , Congelamento , Análise Multivariada , Riboflavina/análise , Tiamina/análise , Fatores de Tempo , Vitamina B 6/análise
18.
Int J Mol Sci ; 13(9): 11173-11187, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109845

RESUMO

Since the primordial of humanity, pollen has been considered a good source of nutrients and energy. Its promising healing properties have also been referred to. The present study aimed to characterize, for the first time, eight commercial pollens from Portugal and Spain available on the market studying the legislation on labeling, pollinic origin, physicochemical and microbiological analyses and identification of yeasts. Eleven botanical families were found amongst the samples. The most abundant family and the most dominant pollen was Cistaceae. The moisture content, ash, a(w), pH, reducing sugars, carbohydrates, proteins, lipids and energy were analyzed and the specific parameters were within the specifications required by some countries with legislation regarding these parameters. Microbiologically commercial pollen showed acceptable safety for the commercial quality and hygiene. All samples showed negative results for toxigenic species. The microorganisms studied were aerobic mesophiles, yeasts and moulds, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella and sulfite-reducing Clostridium. During the work, six yeasts species were isolated from pollen, with Rhodotorula mucilaginosa being the most abundant, as it was present in four samples.


Assuntos
Suplementos Nutricionais/análise , Rotulagem de Alimentos , Pólen/química , Pólen/microbiologia , Animais , Abelhas , Suplementos Nutricionais/microbiologia , Pólen/metabolismo , Leveduras/classificação , Leveduras/isolamento & purificação
19.
Food Chem Toxicol ; 50(12): 4246-53, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981908

RESUMO

The aim of this work was to study four propolis samples from Trás-os-Montes region of Portugal. The propolis samples' color was different, which pollen analysis showed to be due to different botanical sources: Populus sp., Pinus sp., Quercus sp. and Castanea sativa. The data from physicochemical analysis (moisture, soluble and insoluble solids content, pH, conductivity, ash content, wax, total phenolics and flavonoids content) was treated using multivariate statistical tools as cluster heat map, principal components analysis and linear discriminant analysis with the purpose of classifying the sample accordingly to the botanical/geographical origin. The discriminant analysis was applied with stepwise to select the variables that most contribute to sample identification accordingly to pollinic profile. The cross-validation technique was applied, using the leave-one-out procedure, which showed good prediction capabilities of the samples. Microbiologically, the commercial quality was satisfactory, since the samples didn't contain deterioration or pathogenic microorganisms. All the samples studied presented antimicrobial activity against Methicillin-resistant Staphylococcus aureus, in a dose dependent way. The antimicrobial activity was strictly related to the physicochemical composition. This work will allow connecting a particular chemical propolis type to a specific type of biological activity, what is essential for the use in therapeutic applications.


Assuntos
Pólen/química , Própole/análise , Própole/química , Antibacterianos/análise , Antibacterianos/química , Cannabis/química , Fenômenos Químicos , Clostridium/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Flavonoides/análise , Concentração de Íons de Hidrogênio , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenóis/análise , Pinus/química , Populus/química , Portugal , Quercus/química , Salmonella/efeitos dos fármacos , Esporos Bacterianos
20.
Molecules ; 17(7): 8561-77, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22805507

RESUMO

In this study the characterization of a total of 60 honey samples with Protected Denomination of Origin (PDO) collected over three harvests (2009-2011, inclusive), from the Northeast of Portugal was carried out based on the presence of pollen, physicochemical and microbiological characteristics. All samples were found to meet the European Legislation, but some didn't meet the requirements of the PDO specifications. Concerning the floral origin of honey, our results showed the prevalence of rosemary (Lavandula pedunculata) pollen. The microbiological quality of all the analyzed samples was satisfactory, since fecal coliforms, sulfite-reducing clostridia and Salmonella were absent, and molds and yeasts were detected in low counts. Significant differences between the results were studied using one-way analysis of variance (ANOVA), followed by Tukey's HSD test. The samples were submitted to discriminant function analysis, in order to determine which variables differentiate between two or more naturally occurring groups (Forward Stepwise Analysis). The variables selected were in this order: diastase activity, pH, reducing sugars, free acidity and HMF. The pollen spectrum has perfect discriminatory power. This is the first study in which a honey with PDO was tested, in order to assess its compliance with the PDO book of specifications.


Assuntos
Mel , Rosmarinus , Amilases/análise , Animais , Fungos/isolamento & purificação , Mel/microbiologia , Mel/normas , Humanos , Concentração de Íons de Hidrogênio , Pólen/química , Pólen/fisiologia , Portugal , Rosmarinus/química , Rosmarinus/fisiologia
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