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1.
Food Chem ; 337: 127771, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777564

RESUMO

Faveleira (Cnidoscolus quercifolius) is an emerging Brazilian plant, with seeds rich in edible oil. This study investigates physicochemical properties, chemical composition, thermal and oxidative stability, in vitro and in vivo toxicity, antioxidant, antinociceptive and anti-inflammatory activities of faveleira seed oil. It was observed that the oil has low acidity, value of peroxide, chlorophyll, carotenoids, ß-carotene and high concentrations of unsaturated fatty acids. In addition to presenting thermal and oxidative stability and high total phenolic content, with vanillin, eugenol and quercetin were predominating. The oil showed no toxicity in vitro and in vivo, and presented antioxidant, anti-inflammatory and antinociceptive activities. These findings provide relevant and appropriate conditions for processing of faveleira seed oil as functional food.

2.
Int J Biol Macromol ; 163: 1127-1135, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653372

RESUMO

This study aimed to verify the action of edible chitosan-citric acid (CHI-CA) coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava. Chitosan was obtained from Litopenaeus vannamei shells using high temperature and short exposure times. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of CHI-CA against C. gloeosporioides were determined by macrodilutions at 28 °C/120 h in the absence/presence of CHI-CA (0-10 mg/mL). Scanning electron microscopy was used to evaluate morphological changes in the fungus. Guava slices were coated with CHI-CA (MIC) or 5 mg/mL glycerol (control). Rot incidence and physicochemical, physical, and microbiological factors were determined at 0, 3, 7, and 14 days at 24 °C and 4 °C. Chitosan presented typical structural characterization, 64% deacetylation, and a molecular weight of 1.6 × 104 g/mol. CHI-CA exhibited MIC and MFC values of 5 mg/mL and 10 mg/mL, respectively, and promoted changes in the morphology and cell surface of fungal spores. The fresh-cut guava coated with CHI-CA maintained quality parameters during storage and preserved their sensorial characteristics. Therefore, the use of CHI-CA as a coating is a promising strategy for improving postharvest quality of fresh-cut fruits.

3.
Biotechnol Lett ; 42(3): 437-443, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31933056

RESUMO

This study aimed to evaluate the production of carotenoid pigments by Rhodotorula spp. in submerged fermentation, using residual glycerin from biodiesel production as a carbon source. Chromatographic analysis by HPLC showed that the residual glycerin used as substrate was 57.88% composed of glycerol. The best growth conditions were found in the fermentation medium composed of residual glycerin at a concentration of 30 g/L and pH 9. From all the Rhodotorula strains tested, R. minuta URM6693 was selected because of their performance and adaptation in all culture media assayed. The maximum volumetric production of carotenoids was found at 48 h (equivalent to 17.20 mg/L, for the R. minuta). The production of ß-carotene since the first 24 h of fermentation reach a final concentration of 1.021 mg/L. The yeast Rhodotorula minuta proved its capability to efficiently convert the substrate (mainly at the concentration of 50 g/L), obtaining products of biotechnological interest.


Assuntos
Glicerol/metabolismo , Rhodotorula/crescimento & desenvolvimento , beta Caroteno/biossíntese
4.
Int J Dent ; 2018: 1351925, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29853891

RESUMO

An experimental dentifrice containing nano-silver fluoride (NSF) and a sodium fluoride (NaF) toothpaste were tested in vitro, against S. mutans, to evaluate the minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), antiadherence, antiacid, enamel microhardness, and OCT. The microdilution technique was used to determine the MIC and MBC. Fragments of deciduous enamel were treated with dentifrice slurries, containing bacterial suspension and PBS-treated saliva. The quantification of the microorganisms that adhered to the enamel was determined after 24 hours of incubation, and media pH readings were performed after 2 hours and 24 hours. Deciduous teeth were evaluated for microhardness and OCT during 14 days of pH cycling. Data were statistically analyzed using Student's t-test, Mann-Whitney U test, ANOVA, and Tukey tests at 5% of significance. Dentifrices containing NSF presented a lower MIC and higher statistically significant results compared to NaF dentifrices with respect to preventing bacterial adhesion and pH decreases. NSF and NaF dentifrices showed the same ability to avoid enamel demineralization corroborated by the OCT images. The NSF formulation had a better antibacterial effect compared to NaF dentifrices and similar action on the demineralization of enamel indicating their potential effectiveness to prevent caries.

5.
Int J Biol Macromol ; 93(Pt A): 896-903, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27642129

RESUMO

The present study aimed to evaluate the antimicrobial activity and cytotoxicity of colloidal chitosan - silver nanoparticle - fluoride nanocomposites (CChAgNpFNc), with different silver nanoparticle shapes and sizes. The syntheses of CChAgNpFNc were performed with silver nitrate added to a chitosan solution, addition of a sodium borohydride solution and solid sodium fluoride. Solution of ascorbic acid was added to synthesize larger silver nanoparticles. CChAgNpFNc obtained: S1- 100% spherical, 8.7±3.1nm; S2- 97% spherical, 15.0±7.9nm and 2.5% triangular, 22.2±9.5nm; S3- 77.3% spherical, 31.8±10.4nm, 15.9% triangular, 27.1±10.1nm and 6.8% elliptical, 33.2±7.8nm; and S4- 75.2% spherical, 43.2±14.3nm; 23.3% triangular 38.2±14.8nm, and 1.5% elliptical 38.4±11.6nm. The CChAgNpFNc showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans, by microdilution technique. The influence on the growth of microorganisms was evaluated using a fluorescence assay, and showed an increasing lag phase and a decreasing log phase. Cytotoxicity was investigated using Artemia salina and MTT assays. The S3 and S4 samples exhibited low cytotoxicity. The S1 and S2 samples inhibited murine macrophages and revealed lethal dose concentrations above 1000mg/mL that were classified as moderately toxic. Thus, CChAgNpFNc are potential options for the control of multiple-drug-resistant microorganisms and do not represent substantial risks to human health.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Fluoretos/farmacologia , Nanopartículas Metálicas/toxicidade , Nanocompostos/toxicidade , Animais , Antibacterianos/química , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Coloides , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fluoretos/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Nanocompostos/química , Nanocompostos/ultraestrutura , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Células RAW 264.7 , Staphylococcus aureus/efeitos dos fármacos
6.
Molecules ; 20(5): 9054-70, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25996211

RESUMO

In vitro studies have been carried out to establish the nutritional differences between crude and refined vegetable oils; however, the impact of the consumption of these foods on metabolism, in particular the effect of buriti oil, needs to be further evaluated. The aim of this study was to evaluate the biochemical and murine parameters and the vitamin A and E status in young rats fed with diets supplemented with crude or refined buriti oil. The animals (n = 30) were randomized into three groups receiving diet added of soybean oil (control), crude buriti oil (CBO) and refined buriti oil (RBO) for 28 days. Rats fed with diet added of refined buriti oil (RBO) showed reduced total cholesterol (up to 60.27%), LDL (64.75%), triglycerides (55.47%) and enzyme aspartate transaminase (21.57%) compared to those fed with diet added of crude oil. Serum and hepatic retinol and tocopherol were higher by two to three times in CBO and RBO groups compared to the control group, but no differences were observed for murine parameters. The results indicate that buriti oil is an important source of the antioxidant vitamins A and E, and refined buriti oil is suggested as alternative to improve the lipid profile of healthy rats.


Assuntos
Colesterol/metabolismo , Óleos Vegetais/farmacologia , Vitamina A/metabolismo , Vitamina E/metabolismo , Animais , Carotenoides/farmacologia , Colesterol/sangue , Suplementos Nutricionais , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Óleo de Palmeira , Distribuição Aleatória , Ratos , Ratos Wistar
7.
Food Microbiol ; 44: 211-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25084665

RESUMO

The aim of this study was to extract chitosan (CHI) from Mucor circinelloides UCP 050 grown in a corn steep liquor (CSL)-based medium under optimized conditions and to assess the efficacy of the obtained CHI to inhibit the post-harvest pathogenic fungi Aspergillus niger URM 5162 and Rhizopus stolonifer URM 3482 in laboratory media and as a coating on table grapes (Vitis labrusca L.). The effect of CHI coating on some physical, physicochemical and sensory characteristics of the fruits during storage was assessed. The greatest amount of CHI was extracted from M. circinelloides UCP 050 grown in medium containing 7 g of CSL per 100 mL at pH 5.5 with rotation at 180 rpm. CHI from M. circinelloides UCP 050 caused morphological changes in the spores of the fungal strains tested and inhibited mycelial growth and spore germination. CHI coating delayed the growth of the assayed fungal strains in artificially infected grapes, as well as autochthonous mycoflora during storage. CHI coating preserved the quality of grapes during storage, as measured by their physical, physicochemical and sensory attributes. These results demonstrate that edible coatings derived from M. circinelloides CHI could be a useful alternative for controlling pathogenic fungi and maintaining the post-harvest quality of table grapes.


Assuntos
Aspergillus niger/efeitos dos fármacos , Quitosana/farmacologia , Conservação de Alimentos/métodos , Mucor/química , Rhizopus/efeitos dos fármacos , Vitis/microbiologia , Aspergillus niger/crescimento & desenvolvimento , Quitosana/metabolismo , Armazenamento de Alimentos , Mucor/crescimento & desenvolvimento , Mucor/metabolismo , Rhizopus/crescimento & desenvolvimento , Vitis/química , Vitis/crescimento & desenvolvimento
8.
Int J Mol Sci ; 15(5): 9082-102, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24853288

RESUMO

This article sets out a method for producing chitin and chitosan by Cunninghamella elegans and Rhizopus arrhizus strains using a green metabolic conversion of agroindustrial wastes (corn steep liquor and molasses). The physicochemical characteristics of the biopolymers and antimicrobial activity are described. Chitin and chitosan were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, viscosity and X-ray diffraction. The effectiveness of chitosan from C. elegans and R. arrhizus in inhibiting the growth of Listeria monocytogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, Escherichia coli and Yersinia enterocolitica were evaluated by determining the minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC). The highest production of biomass (24.60 g/L), chitin (83.20 mg/g) and chitosan (49.31 mg/g) was obtained by R. arrhizus. Chitin and chitosan from both fungi showed a similar degree of deacetylation, respectively of 25% and 82%, crystallinity indices of 33.80% and 32.80% for chitin, and 20.30% and 17.80% for chitosan. Both chitin and chitosan presented similar viscosimetry of 3.79-3.40 cP and low molecular weight of 5.08×10³ and 4.68×10³ g/mol. They both showed identical MIC and MBC for all bacteria assayed. These results suggest that: agricultural wastes can be produced in an environmentally friendly way; chitin and chitosan can be produced economically; and that chitosan has antimicrobial potential against pathogenic bacteria.


Assuntos
Quitina/metabolismo , Quitosana/metabolismo , Cunninghamella/metabolismo , Rhizopus/metabolismo , Biodegradação Ambiental , Biomassa , Quitina/química , Quitosana/química , Quitosana/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Resíduos Industriais , Testes de Sensibilidade Microbiana
9.
Molecules ; 19(3): 2771-92, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24590203

RESUMO

Microbiological processes were used for chitin and chitosan production with Cunninghamella elegans UCP/WFCC 0542 grown in different concentrations of two agro-industrial wastes, corn steep liquor (CSL) and cassava wastewater (CW) established using a 2² full factorial design. The polysaccharides were extracted by alkali-acid treatment and characterized by infrared spectroscopy, viscosity, thermal analysis, elemental analysis, scanning electron microscopy and X-ray diffraction. The cytotoxicity of chitosan was evaluated for signs of vascular change on the chorioallantoic membrane of chicken eggs. The highest biomass (9.93 g/L) was obtained in trial 3 (5% CW, 8% CSL), the greatest chitin and chitosan yields were 89.39 mg/g and 57.82 mg/g, respectively, and both were obtained in trial 2 (10% CW, 4% CSL). Chitin and chitosan showed a degree of deacetylation of 40.98% and 88.24%, and a crystalline index of 35.80% and 23.82%, respectively, and chitosan showed low molecular weight (LMW 5.2 × 10³ Da). Chitin and chitosan can be considered non-irritating, due to the fact they do not promote vascular change. It was demonstrated that CSL and CW are effective renewable agroindustrial alternative substrates for the production of chitin and chitosan.


Assuntos
Quitina/biossíntese , Quitosana/metabolismo , Cunninghamella/metabolismo , Manihot/química , Águas Residuárias , Zea mays/química , Animais , Biodegradação Ambiental , Biomassa , Caenorhabditis elegans/metabolismo , Quitina/química , Quitina/toxicidade , Quitosana/química , Quitosana/toxicidade , Meios de Cultura , Termodinâmica , Viscosidade
10.
Int J Food Microbiol ; 171: 54-61, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24321603

RESUMO

This study aimed to obtain chitosan (CHI) from Cunninghamella elegans cultivated in corn step liquid (CSL)-based medium under optimized conditions and to assess the efficacy of the obtained CHI in inhibiting Botrytis cinerea and Penicillium expansum in laboratory media and when applied as a coating on table grapes (Vitis labrusca L.). Moreover, the influence of CHI-based coatings on several physical, physicochemical and sensory characteristics of the fruits during storage was assessed. According to the surface response methodology, the best conditions for isolating CHI from C. elegans cultivated in CSL-medium yielded 8.8 g/100mL at pHs between 5.0 and 5.5 and at 180 rpm. CHI from C. elegans inhibited mycelial growth and spore germination and caused morphological changes in the spores of the tested fungal strains. The CHI coatings delayed the growth of the assayed fungal strains in artificially infected grapes. Applying a CHI coating preserved the quality of grapes, as measured by some physical, physicochemical and sensory attributes, throughout the assessed storage time. These results demonstrate the potential of CHI from C. elegans to control post-harvest pathogenic fungi in fruits, in particular, B. cinerea and P. expansum in table grapes.


Assuntos
Botrytis/efeitos dos fármacos , Quitosana/farmacologia , Cunninghamella/química , Frutas/microbiologia , Penicillium/efeitos dos fármacos , Vitis/microbiologia , Botrytis/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Esporos Fúngicos/crescimento & desenvolvimento
11.
Food Microbiol ; 32(2): 345-53, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22986200

RESUMO

This study evaluated the efficacy of the combined application of chitosan (CHI) and Origanum vulgare L. essential oil (OV) in the inhibition of Rhizopus stolonifer URM 3728 and Aspergillus niger URM 5842 on laboratory media and on grapes (Vitis labrusca L.) and its influence on the physical, physicochemical and sensory characteristics of the fruits during storage (25 °C, 12 days and 12 °C, 24 days). The application of mixtures of different CHI and OV concentrations (Minimum Inhibitory Concentration - MIC, 1/2 MIC and 1/4 MIC) inhibited the mycelial growth of the test fungi. The application of CHI and OV at sub-inhibitory concentrations (CHI 1/2 MIC + OV 1/4 MIC; CHI 1/2 MIC + OV 1/2 MIC) inhibited spore germination and caused morphological changes in fungal spores and mycelia, in addition to inhibiting the growth of the assayed fungi strains in artificially infected grapes as well as the autochthonous mycoflora of grapes stored at both room and cold temperature. In general, the application of a coating composed of CHI and OV at sub-inhibitory concentrations preserved the quality of grapes as measured by their physical and physicochemical attributes, while some of their sensory attributes improved throughout the assessed storage time. These results demonstrate the potential of the combination of CHI and OV at sub-inhibitory concentrations to control post-harvest pathogenic fungi in fruits, in particular, R. stolonifer and A. niger in grapes.


Assuntos
Aspergillus niger/efeitos dos fármacos , Quitosana/farmacologia , Conservação de Alimentos/métodos , Óleos Voláteis/farmacologia , Origanum/química , Extratos Vegetais/farmacologia , Rhizopus/efeitos dos fármacos , Vitis/microbiologia , Aspergillus niger/crescimento & desenvolvimento , Quitosana/química , Armazenamento de Alimentos , Frutas/química , Frutas/efeitos dos fármacos , Frutas/microbiologia , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Óleos Voláteis/química , Extratos Vegetais/química , Rhizopus/crescimento & desenvolvimento , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Vitis/química , Vitis/efeitos dos fármacos
12.
Rev. bras. ciênc. saúde ; 12(2): 159-168, 2008. tab
Artigo em Inglês, Português | LILACS | ID: lil-797244

RESUMO

O presente trabalho teve por objetivo avaliar aprevalência da cárie quando utilizadas dietas hipo ehiperglicídicas. Material e Métodos: Realizou-se umexperimento utilizando-se 36 ratos (Rattus norvegicus albinuswistar), de ambos os sexos, distribuídos em 3 grupos: a)dieta hipoglicídica com água fluoretada (1 ppm); b) dietahiperglicídica mais água fluoretada (1 ppm) e c) dietabalanceada mais água fluoretada. Resultados: Em dentesmolares dos animais analisou-se o grau de prevalência e aprofundidade de penetração das lesões de cárie, em funçãodas dietas. Houve efeito diferenciado das dietas, apresentandomaior grau de prevalência de cárie na seguinteordem: hiperglicídica > balanceada > hipoglicídica. Conclusão:Os resultados sugerem que, a diminuição de sacarose nadieta foi importante para reduzir a prevalência da doença cárie...


The present research had the objective ofevaluating the prevalence of caries in hypoglycemic andhyperglycemic. Materials and Methods: An experiment wascarried out with 36 rats (Rattus norvegicus, albinus Wistar),of both sexes, distributed in three groups: a) hypoglycemicdiet with fluoridate water (1ppm); b) hyperglycemic diet plusfluoridate water (1ppm) and c) balanced diet plus fluoridatewater (1ppm). Results: In the animal’s molar teeth was foundthe prevalence level and penetration depth of caries lesions,caused by the diets. Different effects were experience onthe diets, which showed greater level of prevalence of cariesin the following sequence: hyperglycemic > balanced >hypoglycemic. Conclusion: The results indicate that sucrosedecrease on the diet was important to reduce the cariesdisease...


Assuntos
Ratos , Cárie Dentária , Dieta , Flúor
13.
Electron. j. biotechnol ; 10(1): 61-68, Jan. 2007. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-460041

RESUMO

Microbiological processes were used for chitin and chitosan productions by Cunninghamella elegans (UCP 542) grown in a new economic culture medium. The assay was carried out to evaluate the growth of C. elegans using yam bean (Pachyrhizus erosus L. Urban) medium, in different times of growth (24, 48, 72 and 96 hrs), incubated at 28°C in an orbital shaker at 150 rpm. The lyophilized biomass was determined by gravimetry. The polysaccharides were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, titration and viscosity. C. elegans grown in the yam bean medium and produced higher yields of biomass (24.3 g/ mL) in 96 hrs. The high level was chitosan (66 mg/g), and chitin (440 mg/g) were produced at 48 and 72 hrs of growth, respectively. The polysaccharides showed degree of deacetilation and viscosimetric molecular weight as: 6.2 percent and 3.25 x10(4) g/mol for chitin, and 85 percent and 2.72 x 10(4) g/mol for chitosan, respectively. The results obtained suggest high biotechnological potential of yam bean as an economic source to produce chitin and chitosan by C. elegans. In addition, the new medium using yam bean for production of the chitin and chitosan may be used for many purposes to reduce the cost price of fermentation processes.

14.
World J Microbiol Biotechnol ; 23(12): 1719-24, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27517827

RESUMO

An endophytic actinomycete isolated from tubers of yam beam (Pachyrhizus erosus L. Urban) was classified as a novel species nominated Kitasatospora recifensis based in phenotypic and genotypic analysis (16S rDNA gene sequence). Monosporic culture using specific ISP2 media revealed three interspecies, which were identified by DNA southern hybridization (Wild strain 13817 W, Aerial Mycelium strain 13817 AM and Vegetative Mycelium strain 13817 VM). The strains were tested for the production of amylolitic enzymes in alternative media. Maximum yields for both enzymes were observed in starch-casein. Higher α-amylase was obtained with strain 13817 W in starch-urea, and amyloglucosidase with strain 13817 AM in starch-ammonium that are economic sources and may be important for industrial purposes. Type strain (DAUFPE 13817(T) = KCTC 9972(T )= DSM 44943(T)).

15.
Rev. bras. saúde matern. infant ; 5(1): 71-76, jan.-mar. 2005. tab
Artigo em Português | LILACS | ID: lil-399761

RESUMO

OBJETIVOS: verificar a relação da experiência da doença cárie com o grau de ocorrência de Streptococcus mutans, o fluxo salivar e a capacidade tampão da saliva em 111 adolescentes sadios atendidos no Setor de Puericultura do Hospital das Clínicas de Pernambuco MÉTODOS: realizou-se o exame intraoral e o preenchimento de ficha clínica, para determinação do índice CPO-S (Número de superfícies dentárias cariadas, perdidas ou com extração indicada e restauradas). Em seguida coletou-se a saliva para determinação do fluxo salivar e da capacidade tampão. A raspagem dos dentes anteriores foi realizada para quantificação de Streptococcus mutans presente na placa bacteriana. RESULTADOS: a população avaliada foi predominantemente de baixa atividade de cárie, apresentando capacidade tampão da saliva normal e fluxo salivar deficiente. O número de S. mutans da placa bacteriana foi superior a 105 UFC/mg, na maioria da população estudada. CONCLUSÕES: a atividade de cárie foi inversamente proporcional à capacidade tampão e diretamente proporcional a presença de Streptococcus mutans presentes na placa bacteriana. A baixa atividade de cárie na população estudada pode ser atribuída à boa condição do meio bucal promovida pelo número de escovações diárias com dentufícios fluoretados.


Assuntos
Adolescente , Cárie Dentária , Streptococcus mutans
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