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1.
J Food Prot ; 87(10): 100320, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39214464

RESUMO

Limu smoked chicken is a traditional Chinese delicacy; however, polycyclic aromatic hydrocarbons (PAHs) are generated during the smoking process. We developed a pyrolysis process for pear wood liquid smoke with minimal PAH generation. Pear wood liquid smoke products were prepared under different pyrolysis conditions in a self-made pyrolysis reactor, and the total phenol, carbonyl compound, total acid, and PAH contents and PAH toxicity risk were evaluated. With increasing temperatures, the toxicity equivalent ΣPAH of the smoke liquid reached 3.004 µg/kg. With increasing particle sizes, the total phenol content reached 1.6 mg/mL; the phenol content was 5.95 mg/mL. With increasing particle sizes, the toxicity equivalent ΣPAHs of the smoke liquor reached 2.441 µg/kg. The optimal parameters for treating pear wood smoke liquid in the thermal reaction device were a pyrolysis temperature of pear wood of >350 °C, particle size of S2, and sucrose content of 8%.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Pirólise , Fumaça , Madeira , Hidrocarbonetos Policíclicos Aromáticos/análise , Madeira/química , Pyrus/química , Animais , Humanos , Temperatura Alta , Galinhas , Contaminação de Alimentos/análise
2.
Int J Biol Macromol ; 278(Pt 2): 134771, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151864

RESUMO

Non-specific lipid-transfer proteins (nsLTPs) are a group of small, cysteine-rich proteins that are involved in the transport of cuticular wax and other lipid compounds. Accumulating evidence suggests that dynamic changes in cuticular waxes are strongly associated with fruit russeting, an undesirable visual quality that negatively affects consumer appeal in pears. Currently, the regulatory role of nsLTPs in cuticular wax deposition and pear fruit skin russeting remains unclear. Here, we characterized the variations of cuticular waxes in non-treated (russeted) and preharvest bagging treated (non-russeted) pear fruits throughout fruit development and confirmed that the contents of cuticular waxes were significantly negatively correlated with the occurrence of pear fruit russeting. Based on RNA-Sequencing (RNA-Seq) and quantitative real-time PCR (qRT-PCR) analyses, two nsLTP genes (PpyLTP36 and PpyLTP39) were identified, which exhibited high expression levels in non-russeted pear fruit skins and were significantly repressed during fruit skin russeting. Subcellular localization analysis demonstrated that PpyLTP36 and PpyLTP39 were localized to the plasma membrane (PM). Further, transient Virus-Induced Gene Silencing (VIGS) analyses of PpyLTP36 and PpyLTP39 in pear fruits significantly reduced cuticular wax deposition. In conclusion, PpyLTP36 and PpyLTP39 are involved in the transmembrane transport of cuticular wax and are associated with pear fruit skin russeting.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Pyrus , Ceras , Pyrus/metabolismo , Pyrus/química , Ceras/metabolismo , Ceras/química , Frutas/metabolismo , Frutas/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Membrana Celular/metabolismo , Transporte Biológico , Epiderme Vegetal/metabolismo
3.
Molecules ; 29(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38930808

RESUMO

In this study, a beverage made from a combination of Agave sap (AS) and prickly pear juice (PPJ) was analyzed for its nutrients and bioactive and potentially health-promoting compounds. The beverage was evaluated for its ability to act as an antioxidant, regulate glycemic properties, and undergo gut bacterial fermentation in vitro. The major mono- and oligosaccharides present in the beverage were galacturonic acid (217.74 ± 13.46 mg/100 mL), rhamnose (227.00 ± 1.58 mg/100 mL), and fructose (158.16 ± 8.86 mg/mL). The main phenolic compounds identified were protocatechuic acid (440.31 ± 3.06 mg/100 mL) and catechin (359.72 ± 7.56 mg/100 mL). It was observed that the beverage had a low glycemic index (<40) and could inhibit digestive carbohydrases. The combination of ingredients also helped to reduce gas production during AS fermentation from 56.77 cm3 to 15.67 cm3. The major SCFAs produced during fermentation were butyrate, acetate, and propionate, with valerate being produced only during the late fermentation of the AS. This beverage is rich in bioactive compounds, such as polyphenols and dietary fiber, which will bring health benefits when consumed.


Assuntos
Agave , Antioxidantes , Sucos de Frutas e Vegetais , Agave/química , Sucos de Frutas e Vegetais/análise , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/análise , Fermentação , Hidroxibenzoatos/análise , Polifenóis/análise , Polifenóis/química , Pyrus/química , Fenóis/análise , Fenóis/química , Ramnose/análise , Ramnose/química , Catequina/análise , Catequina/química , Catequina/análogos & derivados , Ácidos Hexurônicos
4.
J Sci Food Agric ; 104(11): 6914-6923, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38597278

RESUMO

BACKGROUND: Browning is the key problem hindering the industrialization of pear wine. The use of high-yield glutathione Saccharomyces cerevisiae in the fermentation of pear wine can inhibit browning. Glutathione reductase (GR) can ensure the reduction of glutathione. Spore immobilization of enzymes is a new technology. It is a new attempt to apply spore-immobilized GR in combination with high-yield glutathione S. cerevisiae to inhibit browning of pear wine. RESULTS: Saccharomyces cerevisiae spore immobilization enzyme technology was used to immobilize GR in the spores of mutant S. cerevisiae dit1∆, osw2∆ and chs3∆ and wild-type S. cerevisiae. The enzyme activity of GR immobilized by chs3∆ spores was the highest of 3.08 U mg-1 min-1. The chs3∆ spore-immobilized GR had certain resistance to ethanol, citric acid, sucrose, glucose and proteinase K. Electron microscopy analysis showed that the spore wall of chs3∆ had moderate size holes, which might be the main reason why it immobilized GR with the highest enzyme activity. And the GR was immobilized between the prespore membrane and mannoprotein layer of the spore wall. When chs3∆ spore-immobilized GR (chs3∆-GR) was added to Dangshan pear wine fermented by high-yield glutathione S. cerevisiae JN32-9, the presence of chs3∆-GR could further protect amino acids, polyphenols and glucose from oxidation, thereby reducing the browning of the pear wine during storage by 47.32%. CONCLUSION: GR immobilized by S. cerevisiae spores was effective in inhibiting the browning of pear wine. The method was simple, green and effective and did not increase the production cost of pear wine. © 2024 Society of Chemical Industry.


Assuntos
Fermentação , Glutationa Redutase , Pyrus , Saccharomyces cerevisiae , Esporos Fúngicos , Vinho , Vinho/análise , Pyrus/química , Glutationa Redutase/metabolismo , Glutationa Redutase/genética , Glutationa Redutase/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Reação de Maillard , Frutas/química , Frutas/microbiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química
5.
J Ethnopharmacol ; 282: 114628, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34517063

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pyrus pashia Buch ham ex. D. Don (Kainth) fruit from the Himalayan region is traditionally consumed by native people in the form of decoctions for various clinical conditions including inflammatory diseases. However, scientific studies on the biofunctional properties of Kainth fruits are still scarce. AIM OF THE STUDY: The study is aimed to investigate the anti-inflammatory effects of Kainth fruit extracts using in vitro and in vivo inflammation models. MATERIAL AND METHODS: Free, esterified and bound fractions from the Kainth ethanolic extracts were prepared for determining the anti-inflammatory effect. The levels of 5-LOX and COX-2 were determined in vitro. The protein levels of cytokines (IL-6, TNF-α & IL-10) were quantitated by ELISA method in lipopolysaccharide-stimulated RAW macrophages. Also, the anti-inflammatory potential of the Kainth fruit extracts was determined using the carrageenan-induced mice paw edema model. The bioaccessibility of Kainth fruit extracts was measured using a simulated in vitro digestion system (salivary, gastric and intestinal). RESULTS: The Kainth fruit extracts were partially purified to yield free, esterified and bound phenolics. Free and bound phenolics of Kainth fruits inhibited 5-Lipoxygenase, Cyclooxygenase-2 activities and pro-inflammatory cytokines (Interleukin-6 and tumour necrosis factor-α) expression in vitro. Also, oral administration of these extracts to the carrageenan-injected mice showed an anti-inflammatory effect by decreasing the pro-inflammatory cytokines and reducing the cellular infiltration in paw tissues. Also, both the extracts showed better bioavailability and bioaccessibility in in vitro and in vivo studies. CONCLUSIONS: The results indicated that free and bound phenolics from Kainth fruits that are rich in catechin, epicatechin, arbutin and chlorogenic acid exhibited anti-inflammatory effects and could potentially be used to treat inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Frutas/química , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Pyrus/química , Animais , Anti-Inflamatórios/química , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Carragenina/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Lipopolissacarídeos/toxicidade , Camundongos , Fitoterapia , Extratos Vegetais/química , Polifenóis/química , Células RAW 264.7
6.
Plant J ; 109(1): 47-63, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34695268

RESUMO

Dwarfing rootstocks and dwarf cultivars are urgently needed for modern pear cultivation. However, germplasm resources for dwarfing pear are limited, and the underlying mechanisms remain unclear. We previously showed that dwarfism in pear is controlled by the single dominant gene PcDw (Dwarf). We report here that the expression of PcAGP7-1 (ARABINOGALACTAN PROTEIN 7-1), a key candidate gene for PcDw, is significantly higher in dwarf-type pear plants because of a mutation in an E-box in the promoter. Electrophoretic mobility shift assays and transient infiltration showed that the transcription factors PcBZR1 and PcBZR2 could directly bind to the E-box of the PcAGP7-1 promoter and repress transcription. Moreover, transgenic pear lines overexpressing PcAGP7-1 exhibited obvious dwarf phenotypes, whereas RNA interference pear lines for PcAGP7-1 were taller than controls. PcAGP7-1 overexpression also enhanced cell wall thickness, affected cell morphogenesis, and reduced brassinolide (BL) content, which inhibited BR signaling via a negative feedback loop, resulting in further dwarfing. Overall, we identified a dwarfing mechanism in perennial woody plants involving the BL-BZR/BES-AGP-BL regulatory module. Our findings provide insight into the molecular mechanism of plant dwarfism and suggest strategies for the molecular breeding of dwarf pear cultivars.


Assuntos
Brassinosteroides/metabolismo , Galactanos/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/genética , Esteroides Heterocíclicos/metabolismo , Mucoproteínas/genética , Mucoproteínas/metabolismo , Mutação , Fenótipo , Filogenia , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Pyrus/química , Pyrus/crescimento & desenvolvimento , Pyrus/ultraestrutura , Nicotiana/química , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Nicotiana/ultraestrutura
7.
BMC Complement Med Ther ; 21(1): 219, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470625

RESUMO

BACKGROUND: Pears have been world-widely used as a sweet and nutritious food and a folk medicine for more than two millennia. METHODS: We conducted a review from ancient literatures to current reports to extract evidence-based functions of pears. RESULTS: We found that pears have many active compounds, e.g., flavonoids, triterpenoids, and phenolic acids including arbutin, chlorogenic acid, malaxinic acid, etc. Most of researchers agree that the beneficial compounds are concentrated in the peels. From various in vitro, in vivo, and human studies, the medicinal functions of pears can be summarized as anti-diabetic,-obese, -hyperlipidemic, -inflammatory, -mutagenic, and -carcinogenic effects, detoxification of xenobiotics, respiratory and cardio-protective effects, and skin whitening effects. Therefore, pears seem to be even effective for prevention from Covid-19 or PM2.5 among high susceptible people with multiple underlying diseases. CONCLUSION: For the current or post Covid-19 era, pears have potential for functional food or medicine for both of communicable and non-communicable disease.


Assuntos
Frutas/química , Alimento Funcional , Compostos Fitoquímicos/farmacologia , Pyrus/química , COVID-19 , Flavonoides , Humanos , Fenóis , Triterpenos
8.
Food Chem ; 356: 129658, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838604

RESUMO

A novel fluorescent probe (RA), based on the rosamine skeleton bearing acrylate group, has been reasonably designed and prepared, which employed an addition-cyclization-elimination sequence reaction mechanism to detect cysteine. RA displayed rapid response to cysteine within 1.5 min, and exhibited satisfactory selectivity for cysteine over H2S, glutathione (Glu), and homocysteine (Hcy), due to the formation of seven-membered lactam favored kinetically. Fluorescence ratio was utilized to detect cysteine from 6.0 to 20.0 µM with a detection limit of 0.29 µM. More, RA was used to monitor cysteine in BSA, water, milk, milk powder, cabbage, radish, apple, and pear.


Assuntos
Cisteína/análise , Corantes Fluorescentes/química , Compostos Heterocíclicos com 3 Anéis/química , Leite/química , Plantas/química , Rodaminas/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência/métodos , Água/química , Animais , Brassica/química , Brassica/metabolismo , Glutationa/química , Homocisteína/química , Limite de Detecção , Malus/química , Malus/metabolismo , Leite/metabolismo , Plantas/metabolismo , Pyrus/química , Pyrus/metabolismo , Raphanus/química , Raphanus/metabolismo
9.
Molecules ; 26(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573272

RESUMO

Pears (Pyrus communis L.) cv. Packham's Triumph are very traditional for human consumption, but pear is a highly perishable climacteric fruit with a short shelf-life affected by several diseases with a microbial origin. In this study, a protective effect on the quality properties of pears was evidenced after the surface application of chitosan-Ruta graveolens essential oil coatings (CS + RGEO) in four different concentrations (0, 0.5, 1.0 and 1.5 %, v/v) during 21 days of storage under 18 °C. After 21 days of treatment, a weight loss reduction of 10% (from 40.2 ± 5.3 to 20.3 ± 3.9) compared to the uncoated pears was evident with CS + RGEO 0.5%. All the fruits' physical-chemical properties evidenced a protective effect of the coatings. The maturity index increased for all the treatments. However, the pears with CS + RGEO 1.5% were lower (70.21) than the uncoated fruits (98.96). The loss of firmness for the uncoated samples was higher compared to the coated samples. The pears' most excellent mechanical resistance was obtained with CS + RGEO 0.5% after 21 days of storage, both for compression resistance (7.42 kPa) and force (22.7 N). Microbiological studies demonstrated the protective power of the coatings. Aerobic mesophilic bacteria and molds were significantly reduced (in 3 Log CFU/g compared to control) using 15 µL/mL of RGEO, without affecting consumer perception. The results presented in this study showed that CS + RGEO coatings are promising in the post-harvest treatment of pears.


Assuntos
Quitosana/química , Conservação de Alimentos/métodos , Óleos Voláteis/farmacologia , Pyrus/química , Quitosana/farmacologia , Resposta ao Choque Frio/efeitos dos fármacos , Frutas/química , Fungos/efeitos dos fármacos , Humanos , Óleos Voláteis/química , Óleos de Plantas/química , Pyrus/efeitos dos fármacos , Pyrus/microbiologia , Ruta/química , Temperatura
10.
Food Chem ; 346: 128934, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33418413

RESUMO

Quality loss in pear fruit during storage reduces its marketability for long run. To increase its storability, the efficacy of postharvest dip treatment donor sodium nitroprusside (SNP) 0.000, 0.001, 0.002 and 0.003 mol L-1 were investigated on pear fruit cv. Patharnakh under storage conditions (low temperature 0-1 °C and relative humidity (90-95%). SNP effectively lowered fruit mass loss, retained colour and higher firmness, suppressed browning and respiration rate and sustained soluble solids content, titratable acidity, total phenol content and ascorbic acid thus conserved the fruit quality for longer period. SNP treatments suppressed the activity of polyphenol oxidase and increased activity of superoxide dismutase enzyme. Additionally, the SNP treated fruit exhibited lesser activities of fruit softening enzymes like pectin methylesterase, polygalacturonase and cellulase. Among all, 0.002 mol L-1 SNP concentration was superior to lengthen storability and sensory quality of pear up to 60 d under cold storage.


Assuntos
Fenômenos Químicos/efeitos dos fármacos , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Frutas/química , Nitroprussiato/farmacologia , Pyrus/efeitos dos fármacos , Frutas/efeitos dos fármacos , Pyrus/química , Pyrus/enzimologia
11.
Food Chem ; 338: 128067, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950871

RESUMO

Kainth fruit, as traditional medicine, has been used in the Himalayan region for its health-promoting properties. However, the phytochemicals and lipidomes of Kainth Seed Oil (KSO) are still scarce. Here, we investigated the physicochemical characterization of KSO and its nutraceuticals, antioxidant potentials. Kainth seeds contain 19-20% oil rich in polyunsaturated fatty acids (PUFA, 82.22%), particularly linoleic acid (C18:2). Lipidome analysis of KSO using high-resolution mass spectrometry showed that trilinoleate (C54:6) was the dominant triacylglycerol (TAG) species. Further, the characteristics of PUFA-rich oil were validated by Fourier transforms infrared spectroscopy (FTIR) and Differential Scanning calorimetry (DSC). The nutraceuticals profiling of KSO depicted the presence of tocopherols (86.72 mg) and phytosterols (32.25 mg) in 100 g oil with significant antioxidant activity. The oil cake contained 19.09% protein and minerals and can be a source for dietary protein. Collectively these results suggest that KSO will be a suitable source for PUFA and nutraceuticals potential.


Assuntos
Antioxidantes/química , Suplementos Nutricionais/análise , Óleos de Plantas/química , Pyrus/química , Ácidos Graxos Insaturados/análise , Lipidômica , Espectrometria de Massas , Fitosteróis/análise , Pyrus/metabolismo , Sementes/química , Sementes/metabolismo , Tocoferóis/análise , Triglicerídeos/análise , Triglicerídeos/química
12.
J Sci Food Agric ; 101(3): 853-862, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32726459

RESUMO

BACKGROUND: 'Patharnakh' pear, a dominant cultivar in the Punjab province of India, has a shorter storage life as it matures during the hot and humid weather. Studies have reported that postharvest chemical treatments have a major role in improving the storage life of the fruit. In this study, the efficacy of different concentrations (1, 2, and 3 mmol L-1 ) of salicylic acid (SA), a well-known signaling molecule, was explored to overcome browning and maintain the postharvest quality of the Patharnakh pear during cold storage. RESULTS: SA treated pears were better than the untreated fruits in all of the studied parameters. SA application alleviated the rate of weight loss and respiration, and lowered the decay percentage. The efficacy of SA in the reduction of polyphenol oxidase (PPO) activity, which correlates negatively with the total phenolic content, was quite noticeable. The SA treated fruits exhibited a slower oxidation of the total phenol content by inhibiting the action of PPO and retaining the total phenolic content, leading to lower incidence of browning. SA effectively maintained the ascorbic acid content and superoxide dismutase activity. Total soluble solids, titratable acidity, ascorbic acid, and pH of the pears were highest with the SA treatment. CONCLUSION: The 2 mmol L-1 SA treatment exhibited the best result of reducing fruit decay and tissue browning, and maintaining the postharvest quality parameters of pear up to 60 days of cold storage. © 2020 Society of Chemical Industry.


Assuntos
Conservação de Alimentos/métodos , Frutas/efeitos dos fármacos , Pyrus/química , Ácido Salicílico/farmacologia , Catecol Oxidase/metabolismo , Temperatura Baixa , Cor , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Índia , Oxirredução , Fenóis/química , Fenóis/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/efeitos dos fármacos , Pyrus/metabolismo
13.
Biosci Biotechnol Biochem ; 84(11): 2374-2384, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32674671

RESUMO

Pear juice concentrate prepared by boiling Japanese pear (Pyrus pyrifolia Nakai cv. Nijisseiki) juice can significantly inhibit the activity of tyrosinase, a key enzyme in melanin synthesis in human skin. Using the ethanol extract of pear juice concentrate, we homogeneously purified an active compound that was identified as 5-hydroxymethyl-2-furaldehyde (5-HMF) through 1H- and 13C-NMR and mass spectroscopy. We observed that 5-HMF inhibited the monophenolase and diphenolase activities of mushroom tyrosinase as a mixed-type inhibitor (K i values of 3.81 and 3.70 mmol/L, respectively). In B16 mouse melanoma cells, treatment with 170 µmol/L of 5-HMF significantly reduced α-melanocyte-stimulated melanin synthesis by suppressing the cyclic adenosine monophosphate-dependent signaling pathway involved in melanogenesis. The results of our study indicated that 5-HMF can be potentially used as a skin-lightening agent in the cosmetic industry. Abbreviations: AC: adenylate cyclase; CREB: cAMP response element-binding protein; dhFAME: S-(-)-10,11-Dihydroxyfarnesoic acid methyl ester; DMEM: dulbecco's modified eagle medium; l-DOPA: 3-(3,4-Dihydroxyphenyl)- l-alanine; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HEPES: 4-(2-Hydroxyethyl)-1-piperazine ethane sulfonic acid; 5-HMF: 5-Hydroxymethyl-2-furaldehyde; MITF: microphthalmia-associated transcription factor; α-MSH: α-Melanocyte-stimulating hormone; PKA: protein kinase A; PVDF: polyvinylidene difluoride; SDS: sodium dodecyl sulfate; TRP1: tyrosinase-related protein 1; TRP2: tyrosinase-related protein 2.


Assuntos
Sucos de Frutas e Vegetais/análise , Furaldeído/análogos & derivados , Melaninas/biossíntese , Melanoma Experimental/patologia , Pyrus/química , Animais , Linhagem Celular Tumoral , Furaldeído/isolamento & purificação , Furaldeído/farmacologia , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Oxirredutases/antagonistas & inibidores
14.
Talanta ; 217: 120998, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32498854

RESUMO

Mixed pesticides are usually applied to agricultural products to enhance agricultural production. However, their presence in the environment and food poses serious health risks to humans. Therefore, rapid and reliable detection methods for mixed pesticides residues are in need to minimize potential health hazards. Herein, a nondestructive and sensitive strategy was developed to determine thiram and thiabendazole (TBZ) mixture on fruit surface using surface-enhanced Raman spectroscopy (SERS) technology coupled with interfacial self-assembly gold nanorods (Au NRs) array substrates together with self-modelling mixture analysis (SMA) method. Firstly, a large area high-density Au NRs array was fabricated by organic-aqueous interfacial self-assembly to serve as a sensitive SERS substrate for simultaneously screening of thiram and TBZ on the fruit surface. Then, an SMA method was employed to identify and separate the Raman spectrum for each pesticide from the Raman spectra of the pesticides mixture on the contaminated fruit surface. Results showed that using SERS technique with the SMA method, qualitative and quantitative analyses of a single component from the spectra of the mixture were simultaneously realized, and the resolved pure spectrum of each pesticide was presented. The limits of detection (LOD) of pesticides on the surface of apple, tomato and pear were 0.041, 0.029 and 0.047 ng/cm2 for thiram, and 0.79, 0.76 and 0.80 ng/cm2 for TBZ, respectively. It was anticipated that the proposed SERS detection approach combined with SMA methods should pave the way for detecting multi-analytes in practical applications for agriculture and food safety inspection.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Tiabendazol/análise , Tiram/análise , Ouro/química , Humanos , Solanum lycopersicum/química , Malus/química , Estrutura Molecular , Nanotubos/química , Tamanho da Partícula , Pyrus/química , Análise Espectral Raman , Propriedades de Superfície
15.
Food Chem ; 308: 125665, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655473

RESUMO

The effects of different dissolved oxygen concentrations (DOC) on the browning degree, amino acids, total phenols, reducing sugars, polyphenoloxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) of pear wine, and the relationship between various quality indicators and browning degree were investigated. Dynamic model fitting analysis of the changes of physiochemical indicators of pear wine in the storage process were performed. The importance of the physiochemical indicators effect on the browning of pear wine during the storage process was analyzed by OPLS (orthogonal partial least squares discriminant analysis), and the effect of dissolved oxygen on the browning of pear wine was systematically revealed. The results showed that dissolved oxygen, total phenols and amino acids had the greatest influence on the browning degree of pear wine. It provided a theoretical basis for revealing the browning mechanism and inhibiting the browning of pear wine.


Assuntos
Pyrus/metabolismo , Vinho/análise , Aminoácidos/metabolismo , Catecol Oxidase/metabolismo , Fermentação , Frutas/química , Frutas/metabolismo , Oxirredutases/metabolismo , Peroxidase/metabolismo , Fenóis/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Pyrus/química
16.
Food Chem ; 309: 125693, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31679848

RESUMO

Pickering emulsion coating (CNCP-CH) composed of oleic acid (OA, 1, 2, and 3%, w/w), cellulose nanocrystal (CNC, 0.1, 0.3, and 0.5%, w/w), and 2% chitosan (CH) was optimized for high emulsion stability. It was found that OA concentration played significant role on emulsion stability. Increasing OA from 1 to 3% reduced emulsion stability ~43%, indicated by the thickness of separated cream layer in the emulsion. 'Bartlett' pears (Pyrus communis L.) coated by CNCP-CH containing 1% OA showed significantly reduced ethylene production than that coated with 2% and 3% OA at 1-month of accelerated cold storage at 1.7 °C. The superficial scald on pear peels was only observed on fruit coated by CNCP-CH with 3% OA, but not that with 1% or 2% OA. Therefore, CNCP-CH coating with 1% OA, 0.1% CNC, and 2% CH was suggested for delaying ripening and superficial scald of 'Bartlett' pears during the long-term cold storage.


Assuntos
Celulose/química , Quitosana/química , Etilenos/análise , Armazenamento de Alimentos/métodos , Nanopartículas/química , Pyrus/química , Cromatografia Gasosa , Temperatura Baixa , Emulsões/química , Etilenos/metabolismo , Frutas/química , Frutas/metabolismo , Análise de Componente Principal , Pyrus/metabolismo
17.
Food Chem Toxicol ; 133: 110769, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31442469

RESUMO

Porcine pancreatic lipase (PPL) was used to degrade the mycotoxin patulin (PAT) in pear juice. The dosage of PPL, the initial concentration of PAT, reaction temperature and time were investigated by batch experiments to study the optimal degradation condition. The concentration of PAT in pear juice was determined by high performance liquid chromatography with an ultraviolet detector (HPLC-UV). The results showed that the optimal condition was 0.02 g PPL/mL pear juice at 40 °C for 24 h. The content of organic acids, volatile flavor components, polyphenols, ascorbic acid and the degree of browning reaction in pear juice, relating to the quality of juice, changed insignificantly. Although the initial PAT concentration was very high, the degradation product was confirmed nontoxic by cytotoxicity test of Caco-2 cells. It suggested that PPL could be further considered to be applied in the degradation of PAT in pear juice.


Assuntos
Lipase/química , Micotoxinas/química , Patulina/química , Animais , Ácido Ascórbico/análise , Ácido Ascórbico/química , Células CACO-2 , Ácidos Carboxílicos/análise , Ácidos Carboxílicos/química , Contaminação de Alimentos/prevenção & controle , Sucos de Frutas e Vegetais , Humanos , Hidrólise , Pyrus/química , Suínos , Temperatura
18.
J Agric Food Chem ; 67(30): 8319-8331, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31287308

RESUMO

The layer of cuticular wax covering fruits plays important roles in protecting against disease, preventing non-stomatal water loss, and extending shelf life. However, the molecular basis of cuticular wax biosynthesis in pear (Pyrus) fruits remains elusive. Our study thoroughly investigates cuticular wax biosynthesis during pear fruit development from morphologic, transcriptomic, and gas chromatography-mass spectrometry metabolomic perspectives. Our results showed that cuticular wax concentrations increased during the early stage [20-80 days after full bloom (DAFB)] from 0.64 mg/cm2 (50 DAFB) to 1.75 mg/cm2 (80 DAFB) and then slightly decreased to 1.22 mg/cm2 during the fruit ripening period (80-140 DAFB). Scanning electron microscopy imaging indicated that wax plate crystals increased and wax structures varied during the pear fruit development. The combined transcriptomic and metabolomic profiling analysis revealed 27 genes, including 12 genes encoding transcription factors and a new structural gene (Pbr028523) encoding ß-amyrin synthase, participating in the biosynthesis, transport, and regulation of cuticular wax according to their expression patterns in pear fruit. The quantitative real-time polymerase chain reaction experiments of 18 differentially expressed genes were performed and confirmed the accuracy of the RNA-Seq-derived transcript expression. A model of VLCFAs and cuticular wax synthesis and transport in pear fruit is proposed, providing a mechanistic framework for understanding cuticular wax biosynthesis in pear fruit. These results and data sets provide a foundation for the molecular events related to cuticular wax in 'Yuluxiang' pear fruit and may also help guide the functional analyses of candidate genes important for improving the cuticular wax of pear fruit in the future.


Assuntos
Epiderme/metabolismo , Frutas/crescimento & desenvolvimento , Pyrus/genética , Ceras/metabolismo , Epiderme/química , Frutas/química , Frutas/genética , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Metabolômica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pyrus/química , Pyrus/crescimento & desenvolvimento , Pyrus/metabolismo , Transcriptoma
19.
Food Chem ; 299: 125114, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31326758

RESUMO

UPLC-ESI-HRMS/MS was used to identify the free, esterified and bound phenolic compounds in Kainth fruit extracts. In total, around 17, 15 and 18 free, esterified and bound phenolic compounds respectively were identified. Among these, Procyanidin B2, Epicatechin, Phloridzin, Hesperetin, etc. are being reported for the first time. The total phenolic content of free, esterified and bound fractions were 178.33 ±â€¯6.90, 151.33 ±â€¯7.73 and 707.16 ±â€¯19.77 mg GAE/100 g of fruit. The major phenolic compounds quantified were chlorogenic acid (7.97 mg/100 g), arbutin (7.05 mg/100 g) and catechin (44.56 mg/100 g) in free, esterified and bound form respectively. Various antioxidant assays (DPPH, ABTS, TAC and FRAP) were performed for all the extracts. Among different extracts, the bound phenolics exhibited the highest antioxidant activity. Systematic identification and quantitative profiling of phenolics in Kainth fruit being presented for the first time would help in utilising this fruit for designing functional food formulations.


Assuntos
Antioxidantes/análise , Frutas/química , Fenóis/análise , Pyrus/química , Antioxidantes/química , Cromatografia Líquida , Hidrólise , Fenóis/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
20.
Oxid Med Cell Longev ; 2019: 6714103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281586

RESUMO

In order to evaluate and identify the antioxidant properties and the phytochemical characteristics, as well as the role of the genetic background and the different fruit parts in the definition of fruit quality, we characterized the existing germplasm through nuclear simple sequence repeats (SSRs) and evaluated the genetic divergence between ancient S. Giovanni varieties (Pyrus communis L.) and different types of grafting in relation to some variables of fruit quality. On the peel and pulp of pear varieties, the contents of flavanols, flavonols, and hydroxycinnamic acids as well as total antioxidant capacity were assessed. Their role in plant defences was confirmed by a significantly higher amount in the peel (206.66 ± 44.27, 48.45 ± 13.65, and 31.11 ± 11.94 mg/100 g, respectively) of S. Giovanni pears than in the pulp (71.45 ± 34.94, 1.62 ± 0.83, and 17.05 ± 5.04 mg/100 g, respectively). Data obtained using capillary analysis of SSR indicate unequivocally that the four samples of San Giovanni varieties can be divided into 3 different genetic groups. Cultivar and the different parts of the fruit can exert an action in the definition of the quality product. The use of local varieties and ecotypes can be considered a valid tool to improve food quality and at the same time to support local agrobiodiversity.


Assuntos
Antioxidantes/química , Frutas/química , Compostos Fitoquímicos/química , Pyrus/química , Humanos
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