Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among ...the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC–MS (gas chromatography–mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25mgmL−1 for thyme, 5.0mgmL−1 for basil and marjoram, and 10mgmL−1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.
In this study, we investigated the chemical compositions and antioxidant and antimicrobial activities of propolis produced by the stingless bee Frieseomelitta longipes and the honeybee Apis mellifera ...collected from colonies in North Brazil. In terms of volatile composition, both mono- and sesquiterpenes were detected in the propolis of F. longipes while only sesquiterpenes were detected in that of A. mellifera. Out of 50 volatiles identified in all samples, 26 were found exclusively in F. longipes propolis and 8 were found exclusively in A. mellifera propolis. The chemical profiles of the propolis extracts were determined by atmospheric pressure chemical ionization-mass spectrometry and liquid chromatography-electrospray ionization-tandem mass spectrometry allowed to identify several prenylated benzophenones. A. mellifera extracts exhibited major antioxidant activity as assessed by the 2,2-diphenyl-1-picrylhydrazyl method and all extracts exhibited antioxidant activity as assessed by the β-carotene/linoleic acid method. The ethanolic extracts of the propolis showed promisor activity against all tested microorganisms.
Products made by bees are well-known for their beneficial properties and nutritional value. This association has been proven by scientific studies that describe their composition and biological ...activities. The aim of this study is to portray the state of the art on research regarding stingless bee honey. The search for standards that guide the trade of these products is still portrayed as a future perspective, since there are significant differences in relation to honey from
Apis mellifera
and it often requires additional treatments.
Neste trabalho objetivou-se estudar própolis produzidas em Roraima por Apis mellifera com base na composição química e atividade antioxidante. Coletou-se amostras em áreas de floresta (MJ) e savana ...(BF) para posterior obtenção dos extratos etanólicos. Quantificou-se fenólicos e flavonoides, e determinou-se a atividade antioxidante por diferentes métodos. BF apresentou maior teor de fenólicos (40,89 mg ácido gálico/g própolis), flavonoides (3,41 mg quercetina/g; própolis 4,75 mg pinocembrina/g própolis) e se destacou com 85,89 µmol trolox/g própolis no ensaio com DPPH. No entanto, por β-caroteno/ácido linoleico o percentual praticamente não variou entre MJ (85,88%) e BF (84,98%).
Rationale
Propolis has a great diversity in its composition due to numerous factors; therefore, each study is an important contribution to the knoFwledge of its composition and biological action. The ...objective of this study was to determine the chemical profile and biological activity of propolis produced by Scaptotrigona depilis.
Methods
Extracts with 70% ethanol (EPE70) and with cereal alcohol (CAPE) were elaborated, and then characterized using UHPLC‐ESI(+)‐MS/MS. Volatile compounds were extracted and then characterized using gas chromatography mass spectrometry (GC–MS). In addition, antimicrobial activities were verified against resistant strains.
Results
The volatile compounds of propolis predominantly consist of sesquiterpenes. Using the exploratory metabolomic approach, compounds of different classes were putatively identified in the ethanolic extracts, of which the most representative were terpenes, and some of the sesquiterpenes identified among the volatiles were also detected. The extracts were shown to be active against Escherichia coli and Staphylococcus aureus bacteria with a minimum inhibitory concentration (MIC) of 0.5 and 1.0 mg mL−1, respectively.
Conclusions
The molecular network approach proved to be determining the chemical profile of S. depilis propolis rapidly and accurately, and led to the identification of lipophilic compounds. The identification of compounds using GC–MS and UHPLC‐ESI(+)‐MS/MS is complementary and useful for the characterization of propolis.
•The highest pigment and vitamin C concentrations were observed in the fruit peels.•The highest ascorbic acid concentrations occurred at 88 DAA and then decreased.•The maximum antioxidant activity ...indicated by ORAC and DPPH was detected at 88 DAA.•The flavonoids concentrations generally increased during fruit maturation.•Vitamin C conferred a functional potential to camu-camu fruits.
The goal of this study was to determine the antioxidant activities and bioactive compound concentrations in camu-camu fruits during fruit development. For 6 seasons (years), camu-camu fruits were marked and harvested at 53, 60, 67, 74, 81, 88, 95, and 102 days after anthesis (DAA) from a rural property, located in the municipality of Cantá/RR. The highest pigment (carotenoids, flavonoids, and anthocyanins) and vitamin C concentrations were observed in the fruit peels. In contrast, the highest flavonoid and anthocyanin concentrations were measured in the fully ripe fruits that were harvested at 102 DAA. The highest carotenoid concentrations were recorded in fruits harvested at 53 DAA and decreased with fruit ripening. The highest ascorbic acid concentrations occurred at 88 DAA and decreased when the fruits became completely red. In addition, the highest total phenol concentrations and antioxidant activities were observed during this period. Consequently, camu-camu can serve as a functional food.
The total phenolic and flavonoid content, color, and antioxidant activity were evaluated from ten honey samples from Apis mellifera L. collected from Roraima State, Brazil. The total phenolic content ...was determined using the Folin-Ciocalteu reagent and ranged from 250 to 548 mg gallic acid kg-1 of honey. The total flavonoid content was obtained using two methods: total flavones/flavonols were determined with aluminum chloride, and flavonones/dihydroflavonols were determined with 2,4-dinitrophenylhydrazine. The results ranged from 9 to 48.6 mg of quercetine kg-1 of honey and 1805 to 2606 mg of pinocembrin kg-1 of honey, respectively. Antioxidant activity was measured with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavengers, and the results of the IC50 ranged from 3.17 to 8.79 mg/mL. Statistical analysis demonstrated positive correlations between color intensity, flavone and flavonol content, and phenolic content and negative correlations with antioxidant capacity.
Bees are becoming more and more valued for the extremely important role they play in ecological communities, especially for their pollinating action. The state of Roraima, Brazil has areas of native ...vegetation and variety of stingless bees, and this potential is still untapped. The objective of this study was to determine the chemical composition of materials collected from the nests of Frieseomelitta silvestrii (FRIESE, 1902), identified in São Luiz, in Roraima state, Brazil. The chemical composition of the collected material was determined by gas chromatography coupled to mass spectrometry (GC-MS). The dichloromethane extracts of propolis, cerumen threads and resin present in the stingless bee nest presented differentiated profiles with the occurrence of low polarity compounds.
(Rottb.) Maas was collected in Serra do Tepequém, municipality of Amajari, state of Roraima, Brazil. The essential oil was obtained from the fresh leaves by hydrodistillation using a Clevenger ...apparatus and analysed using GC-FID and GC-MS. The oil provided a yield of 0.6% (
), which, in the analysis of its contents, presented a higher concentration of sesquiterpenes, with
-phellandrene (23.10%), 16-oxo-8(17),12(
)-labdadien-15-oic acid (17.05%),
-caryophyllene (10.28%), valencene (5.27%) and
-aromadendrene (3.52%) being the most abundant. The antioxidant activity of the essential oil was determined using two methods, and indicated significant activity by both. Using the DPPH method, the essential oil presented an IC
of 1.470 ± 0.0264 mg.L
and an inhibition of the
carotene/linoleic acid oxidation system of 76.43 ± 0.80%.
Aerial parts of Elyonurus muticus were collected in the four seasons of the year in the Brazilian Pantanal and subjected to extractrion with cold ethanol and to hydrodistillation. Sesquiterpenoids ...(E)-caryophyllene, bicyclogermacrene, spathulenol and caryophyllene oxide were the main components identified in the essential oils and their concentrations varied according to the plant collection period. The essential oils and the ethanolic crude extracts were active against Bacillus cereus MIP 96016, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923 and were not active against Escherichia coli ATCC 25922. The antibacterial activities varied according to the plant collection period.
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