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1.
Pestic Biochem Physiol ; 168: 104643, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32711776

RESUMO

Essential oils are promising substitute for chemical pesticides with the inherent resistance by pests, environmental and health effects on humans. In this study, the chemical composition of essential oil extracted from Citrus sinensis peel was characterized, the insecticidal activities of the oil and its constituents against Callosobrunchus maculatus (Cowpea weevil) and Sitophilus zeamais (maize weevil) were investigated and the underlying insecticidal mechanism were elucidated. The essential oil was extracted by hydro-distillation and characterized using gas chromatography-mass spectrometry (GC-MS). Insecticidal activity was determined by contact and fumigant toxicity assay. The inhibitory effect of the oil and its constituents on acetylcholinesterase (AChE), Na+/K+-ATPase and glutathione-S- transferase (GST) activity were assayed using standard protocols. The total number of volatile compounds detected in C. sinensis essential oil was eighteen (18). d-limonene (59.3%), terpineol (8.31%) and linalool (6.88%) were the major compounds present in the essential oil. Among the tested essential oil compounds, terpineol showed highest contact toxicity against C. maculatus (LD50 =17.05 µg/adult) while 3-carene showed highest contact toxicity against S. zeamais (LD50 =26.01 µg/adult) at 24 h exposure time. Citral exhibited the highest fumigant toxicity against C. maculatus and S. zeamais with LC50 value 0.19 and 2.02 µL/L air at 24 h respectively. Acetylcholinesterase and Na+/K+-ATPase activities were significantly inhibited by C. sinensis oil and its constituents in both C. maculatus and S. zeamais as compared to control. This study indicates that C. sinensis essential oil and its constituents have potential to be developed into botanical pesticides.


Assuntos
Citrus sinensis , Inseticidas , Óleos Voláteis , Gorgulhos , Animais , Limoneno
2.
Environ Sci Pollut Res Int ; 27(27): 33882-33889, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535830

RESUMO

This study was conducted to analyze the residue levels of tepraloxydim in banana and sweet orange. Successive liquid-liquid extraction and cartridge clean-up method for tepraloxydim determination in banana and sweet orange were developed and validated by HPLC. The developed method was validated, and the recovery and LOQ of tepraloxydim were 79.3-99.5% and 0.02 mg kg-1, respectively. Among the 48 banana and 34 sweet orange samples, tepraloxydim was detected in two (0.03 mg kg-1) and four samples (0.03-0.05 mg kg-1), respectively. A risk assessment of tepraloxydim in banana and sweet orange was conducted by calculating the percent ratio of estimated daily intake (EDI) and acceptable daily intake (ADI). The ADI of tepraloxydim was 0.05 mg kg-1 day-1, and the EDIs of it from banana and sweet orange were 6.3 × 10-6 and 5.1-8.5 × 10-6, respectively. The percent of EDI to ADI of tepraloxydim was 0.013 and 0.010-0.017%, respectively. These results showed that the tepraloxydim levels in this study might not be harmful to human beings.


Assuntos
Citrus sinensis , Musa , Cromatografia Líquida de Alta Pressão , Cicloexanonas , Humanos , Oximas , Medição de Risco
3.
Food Chem ; 329: 127130, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516707

RESUMO

Untargeted metabolomics was used to investigate the differences between orange juices from concentrate or not. Although no distinctive separation could be observed from principal component analysis for all samples, student's t-test, fold change, orthogonal projection to latent structures discriminant and detection rate analyses were conducted to find the latent potential markers. Subsequently, 91 and 42 potential markers were defined in positive/negative mode. Thirteen of them, l-glutamine, carvone, erucamide, lysoPE (16:0/0:0), oleic acid, α-linolenic acid and 7 tripeptides (reported for the first time in orange juice) were identified with standards. A partial least squares discriminant analysis model, based on the potential markers in positive mode by direct analysis in real time mass spectrometry-quadrupole time of flight (DART-QTOF) with 9 s acquisition time, was constructed and validated with 97% and 95% accuracy for training and test. The model was applied to commercial samples successfully, and an NFC brand was found highly suspicious.


Assuntos
Citrus sinensis/metabolismo , Sucos de Frutas e Vegetais/análise , Biomarcadores , Cromatografia Líquida de Alta Pressão , Citrus sinensis/química , Análise Discriminante , Análise dos Mínimos Quadrados , Espectrometria de Massas , Metabolômica
4.
Pestic Biochem Physiol ; 165: 104505, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359555

RESUMO

Blue mold caused by Penicillium italicum is an important postharvest disease of citrus fruit. The antifungal activity of a flavonone pinocembroside compound obtained from the fruit of Ficus hirta Vahl., was evaluated against P. italicum. Pinocembroside showed antifungal activity against in vitro mycelial growth of P. italicum, with the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 200 and 800 mg/L, respectively. The blue mold development on 'Newhall' navel oranges was inhibited by pinocembroside in a dose-dependent manner. Moreover, pinocembroside might exert its antifungal activity via membrane-targeted mechanism with increasing membrane permeability, reduction of antioxidant enzyme activity and acceleration of lipid peroxidation in the pathogen. This pioneering study suggested that pinocembroside suppressed postharvest blue mold by direct inhibition of P. italicum mycelial growth via membrane-targeting mechanism, thus providing a novel mode of action against traditional fungicides for controlling blue mold of citrus fruit.


Assuntos
Citrus sinensis , Citrus , Fungicidas Industriais , Penicillium , Frutas
5.
PLoS One ; 15(5): e0232448, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32433708

RESUMO

Several Botryosphaeriaceae species are known to occur worldwide, causing dieback, canker and fruit rot on various hosts. Surveys conducted in ten commercial citrus orchards in the northern region of Algeria revealed five species of Botryosphaeriaceae belonging to three genera associated with diseased trees. Morphological and cultural characteristics as well as phylogenetic analyses of the internal transcribed spacer (ITS) region and the translation elongation factor 1-alpha (tef1-α) identified Diplodia mutila, Diplodia seriata, Dothiorella viticola, Lasiodiplodia mediterranea and a novel species which is here described as Lasiodiplodia mithidjana sp. nov.. Of these, L. mithidjana (14.1% of the samples) and L. mediterranea (13% of the samples) were the most widespread and abundant species. Pathogenicity tests revealed that L. mediterranea and D. seriata were the most aggressive species on citrus shoots. This study highlights the importance of Botryosphaeriaceae species as agents of canker and dieback of citrus trees in Algeria.


Assuntos
Ascomicetos/patogenicidade , Citrus sinensis/microbiologia , Doenças das Plantas/microbiologia , Argélia , Ascomicetos/classificação , Ascomicetos/genética , DNA Fúngico/genética , Filogenia , Especificidade da Espécie , Virulência
6.
PLoS One ; 15(5): e0233014, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32433657

RESUMO

Citrus trees produce flushes throughout the year, but there are no criteria established for a precise shoot monitoring in orchards under tropical climate. Methods for quantification of flush dynamics would be useful for horticultural and pest management studies because different insect vectors feed and reproduce on flushes. We estimated the minimum number and distribution of trees for sampling and determined the flushing pattern over time in 'Valencia Late' orange trees grafted onto 'Swingle' citrumelo rootstock. Shoots within a square frame (0.25 m2) on two sides of the canopy were counted and classified by their phenological stage. The minimum number of samples was estimated using the mean number of shoots and area under the flush shoot dynamics (AUFSD). The temporal and spatial distribution analysis was performed by Taylor's power law and by multiple correspondence analysis (MCA). Additionally, a shoot maturity index (SMI) based on visual qualitative assessment of flushes is proposed. Considering the mean number of shoots, it was necessary to sample two sides of 16 trees to reach a relative sampling error (Er) of 25%, whereas by the AUFSD, only five trees were necessary to reach an Er of 10%. Flushes were predominantly randomly distributed over time and space. Testing eight transects, sampled trees should be distributed throughout the block, avoiding sampling concentration in a certain area. MCA showed that the west side and the upper sampling positions of trees were more likely to be associated with younger shoots. AUFSD and the evaluation of both sides of the canopy yielded a smaller number of trees to be assessed. The SMI was a reliable metric to estimate the shoot phenology of orange trees, and correlated well (R2 > 70%) with the mean number of shoots within the square frame. Therefore, SMI has the potential to make shoot monitoring in the field more practical.


Assuntos
Citrus/crescimento & desenvolvimento , Animais , Brasil , Citrus/parasitologia , Citrus sinensis/crescimento & desenvolvimento , Citrus sinensis/parasitologia , Produtos Agrícolas/crescimento & desenvolvimento , Vetores de Doenças , Monitorização de Parâmetros Ecológicos , Interações Hospedeiro-Patógeno , Controle de Pragas/métodos , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Brotos de Planta/crescimento & desenvolvimento , Tamanho da Amostra , Clima Tropical , Tempo (Meteorologia)
7.
Int J Food Microbiol ; 324: 108613, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32224332

RESUMO

This study aimed to develop a pasteurization method against Salmonella enterica serovar Typhimurium in orange juice using low concentrations of naturally derived antimicrobials, ß-resorcylic acid and capric acid, under mild temperature conditions based on their synergistic bactericidal interactions. Response surface methodology was used to construct a model based on four variables, namely ß-resorcylic acid (1, 3, 5, 7, and 9 mM), capric acid (0.05, 0.10, 0.15, 0.20, and 0.25 mM), treatment temperature (35, 40, 45, 50, and 55 °C), and time (1, 2, 3, 4, and 5 min), and the resulting model was used to predict the reduction in the content of fastidious bacteria (S. Typhimurium) in orange juice and to identify the optimal treatment combination for juice pasteurization. A second-order quadratic model for Salmonella reduction showed a high regression coefficient (R2 = 0.9503), and the accuracy of the predictive model was also verified (R2 = 0.9317). The optimal conditions determined by ridge analysis were 8.43 mM ß-resorcylic acid combined with 0.10 mM capric acid at 43.46 °C for 3.03 min, and these yielded an estimated 7.41-log reduction. Treatment times <30 s under the optimal conditions also resulted in a >5.7-log reduction. The combined treatment did not affect either the pH or sugar concentration in brix, and average pH and sugar concentration values of 3.86 and 11.05% were observed, respectively. The distinct advantage of the developed method is its ability to effectively reduce the content of S. Typhimurium over a short time under low temperature conditions through the addition of consumer-preferred naturally derived antimicrobials. The predictive model could be used to determine the most cost-efficient amounts of antimicrobial agents and conditions (treatment temperature and time) for sterilizing orange juice.


Assuntos
Anti-Infecciosos/farmacologia , Citrus sinensis , Sucos de Frutas e Vegetais/microbiologia , Pasteurização/métodos , Salmonella typhimurium/isolamento & purificação , Contagem de Colônia Microbiana , Ácidos Decanoicos/farmacologia , Hidroxibenzoatos/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Temperatura , Fatores de Tempo
8.
Food Chem ; 321: 126701, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283502

RESUMO

The antifungal activity of a library of twenty-four aromatic methoximes was examined against five representative postharvest phytopathogenic fungi. The panel included Penicillium digitatum, Penicillium italicum, Rhizopus stolonifer, Botrytis cinerea and Monilinia fructicola, all of which cause relevant economic losses worldwide as a result of affecting harvested fruits. The minimum inhibitory concentrations and minimum fungicidal concentrations of each compound were defined and the main structure-activity relationships were determined. Although other congeners were more potent, drug likeliness considerations pointed to the methoxime derived from 2,4-dihydroxypropiophenone as the compound with the most suitable profile. The morphology of the colonies of the fungal strains treated with the methoxime was examined microscopically and the compound was also tested in freshly harvested peaches and oranges, exhibiting promising control profiles in both fruits, similar to those of the commercial agents Imazalil and Carbendazim.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Frutas/microbiologia , Oximas/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Citrus sinensis/efeitos dos fármacos , Citrus sinensis/microbiologia , Frutas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oximas/farmacologia , Penicillium/efeitos dos fármacos , Prunus persica/efeitos dos fármacos , Prunus persica/microbiologia , Rhizopus/efeitos dos fármacos , Relação Estrutura-Atividade
9.
Shokuhin Eiseigaku Zasshi ; 61(1): 17-21, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32336714

RESUMO

Oranges are consumed worldwide; however, they contain Cit s 2, a major profilin allergen. We aimed to reduce Cit s 2 levels by preparing mixed orange fresh juice with pineapple, as a convenient method for any kitchen. Cit s 2 levels in orange extracts digested with pineapple extract and its protease bromelain were evaluated with quantitative enzyme-linked immunosorbent assay. Cit s 2 levels decreased according to reaction temperature and time, which was inhibited by iodoacetic acid. Treatment with pineapple extract diluted 40-fold and 0.1 mg/mL of bromelain at 37℃ for 30 min contributed to reducing residual Cit s 2 levels below the cut-off of 15%, respectively. Since this condition can increase the proportion of orange juice and reduce the risk of ingesting the pineapple allergen bromelain, it is considered to be more practical. Broad utilization of proteases in hypoallergenic food products is expected following clinical studies for verification.


Assuntos
Alérgenos/isolamento & purificação , Ananas/enzimologia , Bromelaínas/química , Citrus sinensis , Sucos de Frutas e Vegetais/análise , Manipulação de Alimentos/métodos
10.
J Insect Sci ; 20(2)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32252064

RESUMO

Candidatus Liberibacter asiaticus Jagoueix, Bové, and Garnier (Rhizobiales: Rhizobiaceae) is transmitted by the psyllid Diaphorina citri Kuwayama and putatively causes Huanglongbing disease in citrus. Huanglongbing has reduced yields by 68% relative to pre-disease yields in Florida. Disease management is partly through vector control. Understanding vector biology is essential in this endeavor. Our goal was to document differences in probing behavior linked to sex. Based on both a literature review and our results, we conclude that there is either no effect of sex or that identifying such an effect requires a sample size at least four times larger than standard methodologies. Including both color and sex in statistical models did not improve model performance. Both sex and color are correlated with body size, and body size has not been considered in previous studies on sex in D. citri in terms of probing behavior. An effect of body size was found wherein larger psyllids took longer to reach ingestion behaviors and larger individuals spent more time-ingesting phloem, but these relationships explained little of the variability in these data. We suggest that the effects of sex can be ignored when running EPG experiments on healthy psyllids.


Assuntos
Citrus sinensis/fisiologia , Hemípteros/fisiologia , Herbivoria , Pigmentação , Animais , Tamanho Corporal , Cor , Comportamento Alimentar , Florida , Frutas/fisiologia , Hemípteros/microbiologia , Doenças das Plantas/microbiologia , Rhizobiaceae/fisiologia , Fatores Sexuais
11.
Environ Pollut ; 262: 114303, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155556

RESUMO

Low pH and aluminum (Al)-toxicity often coexist in acidic soils. Citrus sinensis seedlings were treated with nutrient solution at a pH of 2.5, 3.0, 3.5 or 4.0 and an Al concentration of 0 or 1 mM for 18 weeks. Thereafter, malate, citrate, isocitrate, acid-metabolizing enzymes, and nonstructural carbohydrates in roots and leaves, and release of malate and citrate from roots were measured. Al concentration in roots and leaves increased under Al-toxicity, but it declined with elevating nutrient solution pH. Al-toxicity increased the levels of glucose, fructose, sucrose and total soluble sugars in leaves and roots at each given pH except for a similar sucrose level at pH 2.5-3.0, but it reduced or did not alter the levels of starch and total nonstructural carbohydrates (TNC) in leaves and roots with the exception that Al improved TNC level in roots at pH 4.0. Levels of nonstructural carbohydrates in roots and leaves rose with reducing pH with a few exceptions with or without Al-toxicity. A potential model for the possible role of root organic acid (OA) metabolism (anions) in C. sinensis Al-tolerance was proposed. With Al-toxicity, the elevated pH upregulated the OA metabolism, and increased the flow of carbon to OA metabolism, and the accumulation of malate and citrate in roots and subsequent release of them, thus reducing root and leaf Al and hence eliminating Al-toxicity. Without Al-toxicity, low pH stimulated the exudation of malate and citrate, an adaptive response of Citrus to low pH. The interactive effects of pH and pH on OA metabolism were different between roots and leaves.


Assuntos
Citrus sinensis , Citrus , Alumínio , Ânions , Concentração de Íons de Hidrogênio , Folhas de Planta , Raízes de Plantas
12.
Food Chem ; 318: 126506, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32126473

RESUMO

Orange peels were applied as precursors to synthesize carbon dots (CDs) via a one-step green hydrothermal method. The relationship between quantum yield and volatile oils in 14 different varieties of orange peels were investigated. The CDs showed strong blue fluorescence and were further modified with EDTA. Compared with the CDs, the CDs@EDTA exhibited higher sensitivity for Cr(VI) detection with a LOD of 10 nM. The CDs@EDTA was proved to be an effective fluorescent sensor element for Cr(VI) detection in water samples with recoveries ranged from 92.09% to 104.87% (RSD < 5%). Moreover, CDs@EDTA/Cr(VI) system was further developed as a fluorescent "off-on" sensor for ascorbic acid (AA) detection with a LOD of 0.1 µM. Further, the sensor had been successfully applied for the analysis of AA in fresh oranges and commercial orange juices. The recoveries of AA in fresh oranges and orange juices were 92.58-106.76% and 91.54-104.95%, respectively.


Assuntos
Ácido Ascórbico/análise , Carbono/química , Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Espectrometria de Fluorescência/métodos , Cromo/química , Ácido Edético/química , Fluorescência , Frutas/química , Pontos Quânticos/química , Sensibilidade e Especificidade
13.
PLoS One ; 15(2): e0228876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32059041

RESUMO

Citrus Huanglongbing (HLB), which is also known as citrus greening, is a destructive disease continuing to devastate citrus production worldwide. Although all citrus varieties can be infected with 'Candidatus Liberibacter asiaticus' (CaLas), a certain level of HLB tolerance of scion varieties can be conferred by some rootstocks. To understand the effects of rootstock varieties on orange fruit under CaLas stress, comparative iTRAQ proteomic profilings were conducted, using fruit from 'Valencia' sweet orange grafted on the sensitive ('Swingle') and tolerant rootstocks (a new selection called '46x20-04-48') infected by CaLas as experimental groups, and the same plant materials without CaLas infection as controls. The symptomatic fruit on 'Swingle' had 573 differentially-expressed (DE) proteins in comparison with their healthy fruit on the same rootstock, whereas the symptomatic fruit on '46x20-04-48' had 263 DE proteins. Many defense-associated proteins were down-regulated in the symptomatic fruit on 'Swingle' rootstock that were seldom detected in the symptomatic fruit on the '46x20-04-48' rootstock, especially the proteins involved in the jasmonate biosynthesis (AOC4), jasmonate signaling (ASK2, RUB1, SKP1, HSP70T-2, and HSP90.1), protein hydrolysis (RPN8A and RPT2a), and vesicle trafficking (SNAREs and Clathrin) pathways. Therefore, we predict that the down-regulated proteins involved in the jasmonate signaling pathway and vesicle trafficking are likely to be related to citrus sensitivity to the CaLas pathogen.


Assuntos
Citrus sinensis/genética , Citrus sinensis/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Rhizobiaceae/patogenicidade , Citrus sinensis/metabolismo , Defensinas/genética , Defensinas/metabolismo , Resistência à Doença/genética , Frutas/genética , Frutas/metabolismo , Frutas/microbiologia , Reguladores de Crescimento de Planta/genética , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Reação em Cadeia da Polimerase , Proteoma/genética , Proteoma/metabolismo , Proteômica , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
J Agric Food Chem ; 68(10): 3286-3296, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32052973

RESUMO

The bacterial disease Huanglongbing (HLB) has been causing large economic losses in the citrus industry worldwide. Aimed at unraveling the mechanisms of scion/rootstock combination on improving HLB-affected orange juice quality, a specific scion/rootstock combination field trial was designed using three sibling rootstocks and two late-maturing sweet orange scion cultivars. Scion/rootstock combination significantly improved the overall consumer liking of orange juice from the HLB-affected trees. Rootstocks showed significant effects on the consumer liking and overall flavor, while scions had significant effects on the freshness and overall orange flavor intensity of the juice. A PLS-DA model combined with KEGG pathway enrichment analysis and some biomarker metabolites further indicated that scions mainly affected metabolism of alanine, aspartate, and glutamate in orange fruits. Meanwhile, rootstocks had an impact on the biosynthetic pathways of secondary metabolites. Sugars and organic acids were not closely correlated with the overall liking and sensory perception of orange juice. Rather, flavonoids, terpenoids, and volatile aromas played important roles in improving consumer overall liking. These results indicated that an optimum tolerant scion/rootstock combination can make a positive contribution toward improved fruit or juice quality from HLB-affected citrus trees.


Assuntos
Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Melhoramento Vegetal/métodos , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Citrus sinensis/genética , Citrus sinensis/metabolismo , Frutas/química , Frutas/genética , Frutas/metabolismo , Humanos , Metabolômica , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Rhizobiaceae/fisiologia , Metabolismo Secundário , Paladar
15.
Electron. j. biotechnol ; 43: 1-7, Jan. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1087465

RESUMO

Background: Biotechnological processes are part of modern industry as well as stricter environmental requirements. The need to reduce production costs and pollution demands for alternatives that involve the integral use of agro-industrial waste to produce bioactive compounds. The citrus industry generates large amounts of wastes due to the destruction of the fruits by microorganisms and insects together with the large amounts of orange waste generated during the production of juice and for sale fresh. The aim of this study was used orange wastes rich in polyphenolic compounds can be used as source carbon of Aspergillus fumigatus MUM 1603 to generate high added value compounds, for example, ellagic acid and other molecules of polyphenolic origin through submerged fermentation system. Results: The orange peel waste had a high concentration of polyphenols, 28% being condensed, 27% ellagitannins, 25% flavonoids and 20% gallotannins. The major polyphenolic compounds were catechin, EA and quercetin. The conditions, using an experimental design of central compounds, that allow the production of the maximum concentration of EA (18.68 mg/g) were found to be: temperature 30°C, inoculum 2 × 107 (spores/g) and orange peel polyphenols 6.2 (g/L). Conclusion: The submerged fermentation process is an effective methodology for the biotransformation of molecules present in orange waste to obtain high value-added as ellagic acid that can be used as powerful antioxidants, antibacterial and other applications.


Assuntos
Gerenciamento de Resíduos , Citrus sinensis/química , Ácido Elágico , Aspergillus fumigatus , Resíduos/análise , Flavonoides/análise , Biotecnologia/métodos , Taninos Hidrolisáveis/análise , Fermentação , Polifenóis/análise , Compostos Fitoquímicos
17.
J Food Sci ; 85(2): 414-420, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31968404

RESUMO

This study aims to evaluate the impact of a nonconventional pretreatment technique "infrareds free solvent" on the intensification of polyphenols extraction from orange peels. Orange peels were pretreated with infrared heating using a ceramic infrared transmitter from 5 to 25 min at 50 °C. After the addition of the solvent on the pretreated peels, ultrasound treatment was applied on the mixture using an ultrasound generator connected to a titanium ultrasound probe, from 5 to 30 min, at 50 °C. Results showed that the application of ultrasounds on untreated peels enhanced the extraction of polyphenols by 62.5% compared to the conventional solid-liquid extraction. Twenty minutes of infrared pretreatment improved the extraction of polyphenols by 47% with solid-liquid extraction, and 112% with ultrasounds after 30 min compared to solid-liquid extraction from untreated peels. Different combinations of infrared pretreatment and ultrasound assisted extraction were then applied on orange peels. The most advantageous combination in terms of energy consumption and polyphenols extraction has been found for a 20 min infrared pretreatment time and 5 min ultrasound assisted extraction of polyphenols. PRACTICAL APPLICATION: Orange peels are valuable sources of natural antioxidants such as polyphenols. Ultrasound-assisted extraction can improve the extraction of polyphenols compared to conventional solid-liquid extraction. To intensify the extraction process, infrared heating can be used as a simple, low cost, and energy saving method. The combined effect of "infrareds free solvent" and ultrasounds allowed the extraction of the highest yields of polyphenols with a high antiradical capacity and a low energy consumption in comparison to conventional extraction.


Assuntos
Citrus sinensis/química , Frutas/efeitos da radiação , Extratos Vegetais/química , Polifenóis/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Citrus sinensis/efeitos da radiação , Frutas/química , Raios Infravermelhos , Extratos Vegetais/isolamento & purificação , Polifenóis/isolamento & purificação
19.
Food Chem ; 310: 125849, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31753686

RESUMO

Orange juice by-products are proposed as a "green" wall material for the encapsulation of pomegranate peel extract. Stability of crude and encapsulated peel extract was studied under accelerated storage conditions, in terms of phenolic content, antiradical activity, and color. The obtained extracts were used as biofunctional components in cookies, at a phenolics concentration of 5000 ppm. Their effects on phenolics content, antioxidant activity, color, and sensory attributes during baking and storage were examined. It was observed that a large amount of phenolic compounds was degraded during baking even if they were coated. However, encapsulation had a significant effect (p < 0.05) on the retention and the activities of phenolic compounds as compared to non encapsulated. Moreover, the results showed that the extracts could be incorporated in cookies without negatively affecting sensory quality.


Assuntos
Citrus sinensis , Indústria Alimentícia , Sucos de Frutas e Vegetais , Polifenóis/análise , Romã (Fruta)/química , Antioxidantes/análise , Fenóis/análise
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