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1.
Food Res Int ; 179: 113958, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342522

RESUMO

Bee pollen is considered an excellent dietary supplement with functional characteristics, and it has been employed in food and cosmetics formulations and in biomedical applications. Therefore, understanding its chemical composition, particularly crude protein contents, is essential to ensure its quality and industrial application. For the quantification of crude protein in bee pollen, this study explored the potential of combining digital image analysis and Random Forest algorithm for the development of a rapid, cost-effective, and environmentally friendly analytical methodology. Digital images of bee pollen samples (n = 244) were captured using a smartphone camera with controlled lighting. RGB channels intensities and color histograms were extracted using open source softwares. Crude protein contents were determined using the Kjeldahl method (reference) and in combination with RGB channels and color histograms data from digital images, they were used to generate a predictive model through the application of the Random Forest algorithm. The developed model exhibited good performance and predictive capability for crude protein analysis in bee pollen (R2 = 80.93 %; RMSE = 1.49 %; MAE = 1.26 %). Thus, the developed analytical methodology can be considered environmentally friendly according to the AGREE metric, making it an excellent alternative to conventional analysis methods. It avoids the use of toxic reagents and solvents, demonstrates energy efficiency, utilizes low-cost instrumentation, and it is robust and precise. These characteristics indicate its potential for easy implementation in routine analysis of crude protein in bee pollen samples in quality control laboratories.


Assuntos
Pólen , Algoritmo Florestas Aleatórias , Animais , Abelhas , Pólen/química , Proteínas/análise , Suplementos Nutricionais
2.
Neotrop Entomol ; 52(1): 11-23, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36525241

RESUMO

This paper provides the first description of the nesting biology of Ancistrocerus flavomarginatus (Brèthes) (Hymenoptera, Vespidae, Eumeninae), the only species of the genus found in Brazil. Our trap-nest experiments were conducted in two Mixed Ombrophilous Forest fragments and two adjacent matrices in Guarapuava (Paraná state, Brazil) from August 2017 to July 2018. In each area, we set 192 trap nests divided into six groups of 32 units, totalling 768 trap nests. We obtained a total of 47 nests of A. flavomarginatus, the vast majority of them (43, 91.5%) founded in the forest fragments. Most nests were built in wooden traps with a bore diameter of either 5 or 7 mm (19 nests in each type, 80.8%). Nests comprised 1-12 subcylindrical brood cells arranged linearly and separated from one another by transverse partitions of soil mastic. Larvae consumed 6-10 lepidopteran caterpillars before spinning the cocoon. Ancistrocerus flavomarginatus produced up to 6 annual generations (multivoltinism) and its immature forms were parasitized by chrysidid and ichneumonid wasps. The calculated sex ratio (1.78:1) was statistically biased towards males, but since they (21.3 ± 2.0 mg) were significantly lighter than females (50.9 ± 4.0 mg), the resulting investment ratio (1.34:1) was female biased. Males emerged from more external cells and developed significantly faster (27.2 ± 0.46 days) than females (30.1 ± 0.66 days), hence a case of protandry. We demonstrated that A. flavomarginatus is largely dependent on the Atlantic Rainforest and thus that deforestation poses a critical threat to this important species.


Assuntos
Vespas , Masculino , Feminino , Animais , Brasil , Comportamento de Nidação , Larva , Biologia
3.
J Food Sci Technol ; 59(8): 3312-3317, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35872735

RESUMO

Abstract: Rancid taste, pH, and TBARS are important quality parameters of food oxidation, analyzed in a time-consuming and destructive way. Non-destructive characterization of food can be achieved correlating this data with computational vision. Thus, the present study aimed to use RGB digital images to predict sensory rancid taste, pH, and TBARS results in fish burgers. A mobile obtained the digital images, in a controlled environment, and 768 grayscales were performed using RGB histograms. The pH, showed a peak at 21st day of storage, which PCA confirmed by isolating the 21st samples, corroborated by HCA grouping 21st day samples. PLS models from RGB digital images and sensory rancidity, pH and TBARS data, using mean center method and SIMPLS algorithm found models with > 0.97 R2. Thus, any digital image of this batch of burgers, inserted into the model to predict rancid taste, pH and TBARS has high confidence level of prediction.

4.
J Environ Sci Health B ; 55(11): 959-967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32781888

RESUMO

Ipomoea species are troublesome weeds in crop systems through Brazil. Drought stress typically reduces glyphosate efficacy by reducing the foliar uptake of herbicides and their translocation. Using both glyphosate tolerant (GT) and sensitive (GS) plants from Ipomoea grandifolia, I. indivisa and I. purpurea species, this research aimed to (a) correlate amounts of epicuticular wax and tolerance to glyphosate in plants and (b) determine the effect of drought stress (DStress) on changes in the quantity and chemical composition of plant epicuticular waxes. The dose that causes 50% inhibition of growth (GR50) of the biotypes varied between 62 and 1208 (I. grandifolia), 159 and 913 (I. indivisa), and 389 and 1925 g a.e. ha-1 of glyphosate (I. purpurea). There was low inverse correlation (-0.46) between the amount of epicuticular wax and the sensitivity to glyphosate. GT biotypes of the species presented greater plastic capacities than GS biotypes for increasing the amount of epicuticular wax under DStress. The three Ipomoea species exhibited different chemical profiles of waxes supported by IR spectra, which allows for their differentiation. For I. grandifolia and I. purpurea, there was an increase in the polar components in the state without DStress, while for the species I. indivisa, no differences in infrared spectra were detected between the two water conditions.


Assuntos
Glicina/análogos & derivados , Ipomoea/química , Ipomoea/efeitos dos fármacos , Ceras/química , Brasil , Desidratação , Relação Dose-Resposta a Droga , Secas , Glicina/farmacologia , Resistência a Herbicidas , Herbicidas/farmacologia , Folhas de Planta , Glifosato
5.
Bull Environ Contam Toxicol ; 105(1): 127-133, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32548730

RESUMO

In this work the toxicity caused by explosive industries effluent (yellow water) at different levels of toxicity (genetic, cellular and organismal level) was evaluated by the Allium cepa test and the Sorghum sudanense germination. The results showed that the effluent paralyze the mitotic process, keeping the cells in the interphase, decreasing the mitotic index in A. cepa. Chromosomal abnormalities such as c-metaphases, adhesions, breaks, early ascending chromosomes and irregular nucleus were observed for this receptor species. The germination of S. sudanense was reduced, and the development of the radicles were affected, showing reduced tolerance index at the highest concentrations of the effluent. Thus, it is concluded that the effluent from the explosive industry is extremely toxic to the tested organisms, both in cellular and chromosomal level and also for seed germination.


Assuntos
Substâncias Explosivas/toxicidade , Germinação/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Aberrações Cromossômicas , Índice Mitótico , Cebolas/genética , Cebolas/fisiologia , Sorghum
6.
Molecules ; 25(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455579

RESUMO

The aim of this study was to evaluate the most effective extraction condition (temperature, solvent type and time) for recovery of high-value phytochemicals present in the Tabernaemontana catharinensis leaves (TC) and to assess their effect on biochemical parameters in streptozotocin-induced diabetic rats. The extraction of phenolic compounds from TC using a factorial design (FD) 2³, high performance liquid chromatography (HPLC), response surface methodology (RSM) and principal component analysis (PCA) were studied. It was found that the optimal conditions for extraction of phenolics were higher temperature (65 °C) and time (60 min) using ethanol as extractor solvent. In this condition of extraction (A8), total phenolic compounds (TPC) and antioxidant activity (AA) were determined. Additionally, this extract was used to evaluate their effect on antioxidant enzyme activities (superoxide dismutase (SOD) and catalase (CAT)) as well as lipid peroxidation (LP) and protein thiols level (PSH) in the liver and kidneys of normal and diabetic rats. As result, T. catharinensis extract presented TPC content of 23.34 mg EAG/g (equivalent gallic acid) and AA of 34.26 µmol Trolox/g. Phenolic acids (ferulic acid and coumaric acid) and flavonoids (quercetin, rutin and pinocembrin) could be recovered and identified by HPLC. This study indicated an important role of the T. catharinensis extract on free radical inactivation and on the antioxidant defense system in diabetic rats. In fact, the use of T. catharinensis extract restored the normal activity of SOD (p < 0.05) and suppressed malondialdehyde levels in liver and kidney tissues. Thus, the T. catharinensis extract, rich in phenolic compounds, can be responsible for the recover the enzymatic changes in the liver and kidney tissues provoked by diabetes in rats. In addition, the lipid peroxidation rate decreased in the diabetic rats treated with T. catharinensis.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Fenóis/química , Tabernaemontana/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus/patologia , Diabetes Mellitus Experimental/patologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos
7.
Braz J Microbiol ; 44(4): 1049-57, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24688492

RESUMO

Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.


Assuntos
Ácido Clavulânico/metabolismo , Engenharia Metabólica , Mutagênese , Mutação , Streptomyces/metabolismo , Meios de Cultura/química , Lipase/metabolismo , Metanossulfonato de Metila , Streptomyces/efeitos dos fármacos , Streptomyces/genética , Streptomyces/efeitos da radiação , Raios Ultravioleta
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