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1.
Heliyon ; 10(4): e25645, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390185

RESUMO

The method of ultrasound-assisted extraction (UAE) was utilized to extract polyphenols from Jerusalem artichokes tuber (JAT). To determine the ideal values for ultrasound power (UP), extraction time (ET), and temperature (TP), a response surface methodology was utilized. JAT extracts were prepared using UAE and their content of total flavonoids (TFC), total polyphenols (TPC), ferric reducing-antioxidant activity (FRAP), and 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) were determined. Accordingly, optimal settings were obtained where TP = 80.0 °C, ET = 14.99 min, and UP = 99.2 °C. These conditions caused TPC, TFC, FRAP, and % DPPH values to reach 4163.6 mg GAE/kg, 2731.6 mg RE/kg, 2.16 mmol/L, and 85.2% respectively, with general-desirability values of 1.00. In addition, DPPH (R = 0.950) and FRAP (R = 0.962) correlated with TPC, indicating that TPC contributed significantly to antioxidant activity. It was found that UAE extraction yields were higher than conventional extraction yields.

2.
Heliyon ; 7(3): e06507, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33817375

RESUMO

BACKGROUND: The risks associated with direct health spending are high in Cameroon, where almost all household income is spent on health care. Moreover, there is no real social security in Cameroon because of the lack of a universal social protection system. OBJECTIVES: This study aimed to assess the willingness of Cameroonian urban dwellers to subscribe and the amount to pay for voluntary (VCHI) or compulsory community-based health insurance (CCHI). METHODS: A cross-sectional study based on a three-stage stratified cluster random sampling design using a bidding game style based on the contingent valuation approach was performed to in the two largest urban areas of Cameroon (Douala and Yaoundé) evaluate the willingness to pay for the VCHI and CCHI. RESULTS: The results shown that 46% of respondent were willing to join the CCHI and 41% for VCHI. Furthermore, household income, working sector, chronic disease, health priority, and family size were factors mostly associated (p < 0.001) with the willingness to join CCHI or VCHI. Increase in household income has a positive effect on household's desire for both CCHI and VCHI. While for VCHI, increase of children number resulted in an increment of the premium, contrary to the occurrence of chronic ailment which led in the decrease of the bid. CONCLUSIONS: From the results, it is clear that city dwellers in Cameroon are ready to join and pay for community health insurance. This willingness was related to their financial power which resulted in an average insurance premium of 9.03 USD and 8.17 USD, respectively for CCHI and VCHI. That bid was found to be enough for an implementation of these types of health insurance in Cameroon.

3.
Int J Food Microbiol ; 339: 109025, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33360297

RESUMO

This research aimed to isolate lactic acid bacteria (LAB) from apple surface and to reveal their potential to inhibit the growth of Penicillium expansum. Besides, their ability to detoxify fruit juices contaminated with mycotoxin patulin, produced by this fungi, was also studied. The isolation was performed on a typical MRS medium under ambient conditions. The molecular identification of the strains was done by sequencing the 16S rRNA genes. Antifungal activities of the isolated strains have been evaluated using dual agar plate assay protocol. A total of 11 LAB isolates was obtained from apples. These isolates showed phenotypic traits consistent with the genera of LAB. They have been identified as Leuconostoc mesenteroides subsp. mesenteroides and Weissella paramesenteroides. Among them, the strain LB7 showed exciting inhibitory activities in vitro against P. expansum. LB7 also successfully detoxified homemade and commercial fruit juices contaminated with patulin. Further research will bring the application prospects of these LABs in food biocontrol and biopreservation strategies.


Assuntos
Antibiose/fisiologia , Sucos de Frutas e Vegetais/microbiologia , Frutas/microbiologia , Leuconostoc/fisiologia , Malus/microbiologia , Penicillium/fisiologia , Sucos de Frutas e Vegetais/análise , Leuconostoc/genética , Leuconostoc/isolamento & purificação , Patulina/análise , RNA Ribossômico 16S , Weissella/genética
4.
J Food Sci ; 84(10): 2847-2858, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31573687

RESUMO

This study explored the effect of different nonthermal pretreatments, osmosonication (OS), osmotic dehydration, and ultrasound methods on the physical and chemical properties of China- and Ghana-sourced ginger samples under relative humidity convective drying. The chemical properties of pretreated dried ginger slices were assessed for antioxidant properties (ABTS and DPPH); total phenolic content; total flavonoids content; and 4-, 6-, 8-, and 10-gingerol and 6-shogaol levels. The physical properties compared were weight loss, rehydration ratio (RR), texture, and drying kinetics. Results revealed that OS pretreatment led to a higher preservation of the chemical properties with the Ghana-sourced ginger exhibiting the highest values. The OS-treated samples obtained the highest weight losses and RRs, but the RR was higher in the Chinese ginger. OS pretreatment also gave the lowest textural value with the China-sourced samples exhibiting the lowest firmness. Weibull model best fitted the experimental results (R2 > 0.99). PRACTICAL APPLICATION: Ginger remains among the most notable medicinal spices worldwide. It is used as a raw material for the pharmaceutical, beverage, cosmetics, and the food industries. Long-term storage of ginger is one of paramount importance, hence any pretreatment that reduces its moisture content and lessens its drying time but preserves its quality is ideal. In this study, we report the effect of different nonthermal pretreatments, osmosonication, osmotic dehydration, and ultrasound on the physical and chemical properties of China- and Ghana-sourced ginger samples under relative humidity convective drying. The present findings will offer more information in the selection of the best pretreatment technique for drying ginger.


Assuntos
Dessecação/métodos , Manipulação de Alimentos/métodos , Extratos Vegetais/química , /química , Antioxidantes/química , Catecóis/química , China , Álcoois Graxos/química , Flavonoides/química , Gana , Fenóis/química
5.
J Food Biochem ; 43(5): e12832, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31353512

RESUMO

The effect of ultrasound (US), osmotic dehydration (OD), and osmosonication (OS) pretreatments on total phenolic content (TPC), total flavonoids content, (TFC), phytochemical constituents (gingerol derivatives and diarylheptanoids), polyphenol oxidase (PPO), peroxidase (POD), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), cupric ion reducing capacity (CUPRAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power capacity (FRAP), and color of ginger slices dried under relative humidity convective dryer was investigated. OS pretreatment improved the preservation of TPC (13.80-34.79 mg GAE/g d.w), TFC (26.46-62.16 mg CE/g d.w), ABTS (30.37%-86.10%), CUPRAC (36.89-73.97 mg/g), DPPH (50.57%-92.60%), FRAP (26.44-83 mg/g), and phytochemical constituents than US and OD. The OS-treated sample was more effective in inactivating both PPO (12.09%-35.93%) and POD (16.21%-39.58%) enzymes compared to US and OD-treated samples. However, US pretreatment retained the color quality of dried ginger slices than the OS and OD treatments. OS pretreatment (5.43) also increased the total color change (ΔE) of the dried ginger samples compared to US (2.81) and OD (4.60). PRACTICAL APPLICATIONS: Ginger is commonly used in the food, beverage, and pharmaceutical industries owing to their distinctive flavor and various health potentials. However, its high moisture content makes its inappropriate for long-term storage which results in its high perishability. Drying is one of the most common techniques to prolong its shelf life. Hence, any pretreatment for ginger that reduces the moistures content and lessens the drying time by preserving the quality of the crop is of vital importance. Ultrasound, osmotic dehydration, and osmosonication are novel pretreatment techniques that are widely used prior to drying of various agricultural products due to its numerous advantages over conventional methods. Its application in drying of foods could help shorten the drying time, reduce processing costs, improve energy consumption and efficiency, and preserve the physical and nutritional properties of the dried product. The current findings will also offer more information for selecting pretreatment techniques for ginger drying.


Assuntos
Antioxidantes/química , Flavonoides/análise , Fenóis/análise , Compostos Fitoquímicos/química , /química , Antioxidantes/metabolismo , Catecol Oxidase/análise , Catecóis/química , Catecóis/metabolismo , Cor , Dessecação , Álcoois Graxos/química , Álcoois Graxos/metabolismo , Flavonoides/metabolismo , Osmose , Peroxidase/análise , Fenóis/metabolismo , Compostos Fitoquímicos/metabolismo , Sonicação , Ondas Ultrassônicas
6.
Food Chem ; 274: 907-914, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30373027

RESUMO

This present study tested the extent to which 2% w/v trehalose enhanced the proteins expression profile of Hanseniaspora uvarum Y3. Furthermore, it explored the relative gene expression of stilbene synthase (StSy), one of the vital defense-related genes found in the skin of grapes. The proteomics profile revealed that 29 proteins were differentially expressed out of which 26 were significantly up-regulated and 3 were download-regulated. The pathogenesis related (PR) and other protein spots were visible at 97.4 kDa and 14.4 kDa. Peroxiredoxin TSA1 and superoxide dismutase were the main proteins involved in defense response and both proteins were significantly up-regulated. The carbohydrate and energy metabolism proteins were also significantly up-regulated. The results revealed that the treatments were associated with substantial increase in peroxidase activity compared to the control. StSy relative gene expression level was observed to increase by 2.5-fold in grapes treated with the pre-enhanced H. uvarum compared to the control.


Assuntos
Agentes de Controle Biológico , Proteínas Fúngicas/metabolismo , Hanseniaspora/metabolismo , Trealose/farmacologia , Vitis/microbiologia , Aciltransferases/genética , Aciltransferases/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Frutas/microbiologia , Proteínas Fúngicas/análise , Regulação da Expressão Gênica de Plantas , Hanseniaspora/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica/métodos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Vitis/metabolismo
7.
Food Chem ; 250: 148-154, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29412905

RESUMO

This study was conducted to investigate the effect of lactic acid bacteria (LAB) strains on color properties, phenolic profile and antioxidant activities of mulberry juice. Mulberry juice was separately fermented at 37 °C for 36 h using Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus paracasei. The results showed that lactic acid fermentation impacted on the color of the juice. Moreover, the study demonstrated that LABs impacted on the phenolic profile of the juice. Syringic acid, cyanidin-3-O-rutinoside and quercetin were the predominant phenolic acid, anthocyanin and flavonol respectively in the lactic-acid-fermented mulberry juice. The degree of radical scavenging activity was species-specific with the L. plantarum fermented juice having the highest radical scavenging activities. The correlation analysis demonstrated that flavonols and anthocyanins were mostly responsible for the increased in 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity while phenolic acids and flavonols were responsible for 2,2-diphenyl-1-picrylhydrazyl scavenging activity and reducing power capacity of the fermented juice.


Assuntos
Fermentação , Sucos de Frutas e Vegetais/microbiologia , Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Morus/metabolismo , Morus/microbiologia , Fenóis/análise , Antioxidantes/análise , Antioxidantes/química , Cor , Morus/química , Fenóis/química
8.
Food Chem ; 239: 470-477, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28873592

RESUMO

The four different methods of color measurement of wine proposed by Boulton, Giusti, Glories and Commission International de l'Eclairage (CIE) were applied to assess the statistical relationship between the phytochemical profile and chromatic characteristics of sulfur dioxide-free mulberry (Morus nigra) wine submitted to non-thermal maturation processes. The alteration in chromatic properties and phenolic composition of non-thermal aged mulberry wine were examined, aided by the used of Pearson correlation, cluster and principal component analysis. The results revealed a positive effect of non-thermal processes on phytochemical families of wines. From Pearson correlation analysis relationships between chromatic indexes and flavonols as well as anthocyanins were established. Cluster analysis highlighted similarities between Boulton and Giusti parameters, as well as Glories and CIE parameters in the assessment of chromatic properties of wines. Finally, principal component analysis was able to discriminate wines subjected to different maturation techniques on the basis of their chromatic and phenolics characteristics.


Assuntos
Morus , Fenóis , Compostos Fitoquímicos , Dióxido de Enxofre , Vinho
9.
Acta Chim Slov ; 65(4): 823-835, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33562953

RESUMO

In this study mulberry leaf extract biocompounds were encapsulated with sodium carboxymethyl cellulose (0.55%, 0.70%, and 0.75% w/v) or maltodextrin (8%, 10%, and 12% w/v). The outcome of this work demonstrated that maltodextrin showed the highest encapsulation efficiency towards the phenolic acids and 1-deoxynojirimycinin whereas the flavonols and gamma-aminobutyric acid were best encapsulated by sodium carboxymethyl cellulose. Moreover, the antioxidant properties of the encapsulated powders were found to be associated with their nutraceutical constituents. In addition, the powders produced with sodium carboxymethyl cellulose were typified by suitable hygroscopicity, wettability time, glass transition temperature, and bulk properties than those obtained with maltodextrin which was characterized by desirable porosity, water solubility, moisture content, water activity, color, particle, and flowability properties.

10.
Food Chem ; 232: 89-97, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490149

RESUMO

The present study was undertaken to assess accelerating aging effects of high pressure, ultrasound and manosonication on the aromatic profile and sensorial attributes of aged mulberry wines (AMW). A total of 166 volatile compounds were found amongst the AMW. The outcomes of the investigation were presented by means of geometric mean (GM), cluster analysis (CA), principal component analysis (PCA), partial least squares regressions (PLSR) and principal component regression (PCR). GM highlighted 24 organoleptic attributes responsible for the sensorial profile of the AMW. Moreover, CA revealed that the volatile composition of the non-thermal accelerated aged wines differs from that of the conventional aged wines. Besides, PCA discriminated the AMW on the basis of their main sensorial characteristics. Furthermore, PLSR identified 75 aroma compounds which were mainly responsible for the olfactory notes of the AMW. Finally, the overall quality of the AMW was noted to be better predicted by PLSR than PCR.


Assuntos
Manipulação de Alimentos , Morus , Vinho , Humanos , Olfato , Dióxido de Enxofre
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