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1.
Int J Biol Macromol ; 242(Pt 1): 124719, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37150373

RESUMEN

The most remarkable characteristic of European pears is extremely perishable and difficult to store after postharvest softening. Low-temperature storage is one of the most commonly used methods to prolong the shelf life of European pears. However, the regulatory mechanism of the low-temperature delay of the softening of European pears is still unclear. In this study, the fruit firmness, pectin polysaccharide content, pectin-degrading enzyme activity, and pectin degradation gene expression of 'Docteur Jules Guyot' pears under low temperature (LT) and room temperature (RT) were analyzed. It was found that water-soluble pectin (WSP) was significantly negatively correlated with fruit flesh firmness, and the activities of several pectin-degrading enzymes were inhibited under LT storage conditions. In addition, it was also found that the gene expression patterns of PcPME2, PcPME3, PcPG1, PcPG2, PcPL, PcGAL1, PcGAL2, PcGAL4, and PcARF1 were inhibited by LT. The C-repeat binding factors PcCBF1 and PcCBF2 were also inhibited by long-term LT storage. Correlation analysis showed that the expression of PcCBFs was positively correlated with pectin-degradation enzyme genes, and we found that the promoters of many pectin-degradation enzyme genes contain the CRT/DRE motif, which CBF can directly bind. Therefore, it is speculated that long-term low-temperature conditions inhibit pectin degradation through PcCBFs.


Asunto(s)
Pyrus , Pyrus/química , Temperatura , Polisacáridos/metabolismo , Pectinas/metabolismo , Frutas/química
2.
Molecules ; 28(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37110793

RESUMEN

BACKGROUND: The genetic diversity of Sardinian pear germplasm has received limited attention regarding its chemical composition. Understanding this composition can aid in the setting up of resilient, extensive groves that offer multiple products and ecosystem services. This research aimed at investigating the antioxidant properties and phenolic compounds of ancient pear cultivars grown extensively in Sardinia (Italy); Methods: the cultivars Buttiru, Camusina, Spadona, and Coscia (as a reference) were compared. Fruit samples were manually peeled and cut. Their flesh, peel, core, and peduncle were frozen separately, lyophilized, and milled before being analysed; Results: The content of total phenolics (TotP), total flavonoids (TotF), condensed tannins (CT), and antioxidant capacity in each fruit part varied significantly among the cultivars. The TotP content was high in the peduncle (42.2-58.8 g GAE kg-1 DM) and low in flesh (6.4-17.7 g GAE kg-1 DM); Conclusions: the highest values of antioxidant capacity, TotP, NTP, TotF, and CT were found in the flesh of the cultivar Buttiru and in the peel of the cultivar Camusina. Chlorogenic acid was the major individual phenolic compound in peel, flesh and core, whereas arbutin was mostly present in the peduncle. Results can contribute to revise target exploitations of underutilized ancient pear cultivars.


Asunto(s)
Proantocianidinas , Pyrus , Antioxidantes/química , Frutas/química , Pyrus/química , Ecosistema , Extractos Vegetales/química , Fenoles/química , Flavonoides/análisis , Proantocianidinas/análisis
3.
Food Chem ; 409: 135302, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-36623358

RESUMEN

Cell wall polysaccharides and physicochemical properties are the major quality characteristics of fruit, but they are significantly affected by the postharvest disease. In this study, the influence of Alternaria alternata-induced disease on the contents of cell wall polysaccharides and physicochemical properties in 'Korla' pear flesh during storage, as well as their relationships of the optical absorption (µa) and reduced scattering (µs') were explored. The infected pear had lower individual sugars, covalent-soluble pectin, cellulose and hemicellulose contents than the healthy ones. The successive decreases of µa and increases of µs' in pears were observed while the process of pathogen infection. Path-coefficient analysis indicated the ionic-soluble pectin was the main reason responsible for the change of µs' in infected pear at 675 nm and 980 nm. This study indicated the optical properties have the possibility to present the physicochemical characteristics and cell wall polysaccharides of pears during postharvest pathogen infection.


Asunto(s)
Pyrus , Pyrus/química , Polisacáridos/química , Pared Celular/química , Pectinas/análisis , Alternaria , Frutas/química
4.
J Ethnopharmacol ; 282: 114628, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34517063

RESUMEN

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.


Asunto(s)
Antiinflamatorios/farmacología , Frutas/química , Inflamación/tratamiento farmacológico , Extractos Vegetales/farmacología , Polifenoles/farmacología , Pyrus/química , Animales , Antiinflamatorios/química , Araquidonato 5-Lipooxigenasa/genética , Araquidonato 5-Lipooxigenasa/metabolismo , Carragenina/toxicidad , Supervivencia Celular/efectos de los fármacos , Edema/inducido químicamente , Edema/tratamiento farmacológico , Lipopolisacáridos/toxicidad , Ratones , Fitoterapia , Extractos Vegetales/química , Polifenoles/química , Células RAW 264.7
5.
Carbohydr Polym ; 273: 118598, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34560998

RESUMEN

The self-assembly and gelation of low-methoxyl diluted alkali-soluble pectin (LM DASP) from pear fruit (Pyrus communis L. cv. Conference) was studied in water and salt solutions (NaCl and CaCl2, constant ionic strength) without pH adjustment at 20 °C. The samples at different LM DASP concentrations were characterized using rheological tests, Fourier-transform infrared spectroscopy, dual-angle dynamic light scattering and atomic force microscopy. LM DASP from pear fruit (Pyrus communis L.) showed gelling ability. The indices (aggregation index and shape factor) based on light scattering may be useful for the characterization of structural changes in polysaccharide suspension, particularly for the determination of a gel point. The results obtained may be important for the food, cosmetic and pharmaceutical industries where pectin is used as a texturizer, an encapsulating agent, a carrier of bioactive substances or a gelling agent.


Asunto(s)
Geles/química , Pectinas/química , Pyrus/química , Cloruro de Calcio/química , Reología , Cloruro de Sodio/química , Soluciones/química , Agua/química
6.
BMC Complement Med Ther ; 21(1): 219, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34470625

RESUMEN

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.


Asunto(s)
Frutas/química , Alimentos Funcionales , Fitoquímicos/farmacología , Pyrus/química , COVID-19 , Flavonoides , Humanos , Fenoles , Triterpenos
7.
Chem Biodivers ; 18(10): e2100446, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34402208

RESUMEN

Dry MeOH extracts of the twig barks of Pyrus communis subsp. pyraster, P. spinosa and their hybrid P.×jordanovii nothosubsp. velenovskyi, collected in wild in Serbia, were analyzed. By LC/MS, the contents of arbutin (99.9-131.0 mg/g), chlorogenic acid (2.2-6.3 mg/g), catechin (1.0-5.3 mg/g) and total dimeric and trimeric procyanidins (42.2-61.3 mg/g), including procyanidin B2 (8.9-17.2 mg/g), were determined. Colorimetrically, high contents of total phenolics (436.2-533.4 mg GAE/g) and tannins (339.4-425.7 mg GAE/g), as well as strong total antioxidant activities (FRAP values 4.5-5.9 mmol Fe2+ /g), and DPPH (SC50 =6.6-7.1 µg/ml) and hydroxyl radical (SC50 =447.1-727.7 µg/ml) scavenging abilities were revealed. In vitro, all extracts exhibited notable inhibition of α-amylase (IC50 =310.8-617.7 µg/ml) and particularly strong inhibition of α-glucosidase (IC50 =2.1-3.7 µg/ml). Molecular docking predicted that among identified compounds procyanidin B2 is the best inhibitor of these carbohydrate-digesting enzymes. Obtained results showed that the barks of investigated Pyrus hybrid and its parent taxa have similar composition and bioactivity.


Asunto(s)
Antioxidantes/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/metabolismo , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Modelos Moleculares , Fenoles/química , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Pyrus/química , alfa-Amilasas/metabolismo
8.
Food Chem ; 350: 129025, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609938

RESUMEN

Silver-coated gold nanoparticles (Au@AgNPs) were optimized with different gold (Au) core sizes and modified surface with mercaptooctane (MCO) to determine fungicide residues in pear fruit extracts. The developed MCO/Au@AgNPs with a gold core size of 28 nm and silver shell thickness of 6 nm exhibited high sensitivity and significant enhancement of Raman scattering in detecting tricyclazole (TCZ) and thiram fungicides in standard and pear fruit samples. The detection limits for TCZ and thiram in the pear fruit extracts were 0.005 and 0.003 ppm with coefficients of determination of (R2) of 0.9984 and 0.9971, percent recovery ranging from 82.7 to 107.4% and 80.7 to 109.8%, and relative standard deviation (RSD) of 1.5 to 7.9% and 3.7 to 9.5%, respectively. Results showed that this easily prepared method could be employed as SERS active platforms for the rapid assessment of trace contaminants of agrochemicals in agriculture production.


Asunto(s)
Fungicidas Industriales/análisis , Oro/química , Nanopartículas del Metal/química , Pyrus/química , Plata/química , Tiazoles/química , Tiram/análisis , Límite de Detección , Extractos Vegetales/análisis , Reproducibilidad de los Resultados , Espectrometría Raman/métodos
9.
Molecules ; 26(3)2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33573272

RESUMEN

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.


Asunto(s)
Quitosano/química , Conservación de Alimentos/métodos , Aceites Volátiles/farmacología , Pyrus/química , Quitosano/farmacología , Respuesta al Choque por Frío/efectos de los fármacos , Frutas/química , Hongos/efectos de los fármacos , Humanos , Aceites Volátiles/química , Aceites de Plantas/química , Pyrus/efectos de los fármacos , Pyrus/microbiología , Ruta/química , Temperatura
10.
J Sci Food Agric ; 101(11): 4473-4480, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33432579

RESUMEN

BACKGROUND: The greatest hurdle to commercial marketing of fresh-cut fruits and vegetables is limited shelf life due to microbial hazards and quality deterioration. Atmospheric cold plasma (ACP) is an emerging non-thermal technology with significant potential to improve the safety and storability of fresh products. The objective of this study was to evaluate the effects of ACP, generated in sealed packaging, on the qualitative, metabolic and microbial stability of fresh-cut pears during simulated cold storage. RESULTS: ACP treatments were effective in inhibiting the growth of mesophilic aerobic bacteria, yeast and mold, particularly CP3 (65 kV, 1 min), which could prolong shelf life to the greatest extent. While decontamination was not always associated with an increase in plasma intensity. Moreover, at 65 kV for 1 min, ACP treatment had the potential to retard respiration, and maintain organoleptic properties and other quality attributes. Additionally, peroxidase and pectin methylesterase (PME) activities were reduced immediately after treatments. These effects were dependent on treatment voltage and time, while a subsequent recovery in activity was only observed for PME. CONCLUSION: The results obtained from this study will contribute to an understanding of the effects of in-package ACP treatments on the storability and microbial safety of fresh-cut pears. This knowledge could be beneficial in reducing quality losses for fresh-cut pears and the preservation of other products. © 2021 Society of Chemical Industry.


Asunto(s)
Conservación de Alimentos/métodos , Frutas/química , Gases em Plasma/farmacología , Pyrus/metabolismo , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Hidrolasas de Éster Carboxílico/metabolismo , Embalaje de Alimentos , Conservación de Alimentos/instrumentación , Frutas/metabolismo , Frutas/microbiología , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Peroxidasa/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/química , Pyrus/microbiología , Control de Calidad
11.
Food Chem ; 338: 128067, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32950871

RESUMEN

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.


Asunto(s)
Antioxidantes/química , Suplementos Dietéticos/análisis , Aceites de Plantas/química , Pyrus/química , Ácidos Grasos Insaturados/análisis , Lipidómica , Espectrometría de Masas , Fitosteroles/análisis , Pyrus/metabolismo , Semillas/química , Semillas/metabolismo , Tocoferoles/análisis , Triglicéridos/análisis , Triglicéridos/química
12.
J Sci Food Agric ; 101(3): 853-862, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32726459

RESUMEN

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.


Asunto(s)
Conservación de Alimentos/métodos , Frutas/efectos de los fármacos , Pyrus/química , Ácido Salicílico/farmacología , Catecol Oxidasa/metabolismo , Frío , Color , Conservación de Alimentos/instrumentación , Almacenamiento de Alimentos , Frutas/química , Frutas/metabolismo , India , Oxidación-Reducción , Fenoles/química , Fenoles/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/efectos de los fármacos , Pyrus/metabolismo
13.
Molecules ; 25(23)2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33260963

RESUMEN

Metabolites play vital roles in shaping the quality of fresh fruit. In this study, Korla pear fruit harvested from twelve orchards in South Xinjiang, China, were ranked in sensory quality by fuzzy logic sensory evaluation for two consecutive seasons. Then, gas chromatography-mass spectrometry (GC-MS) was applied to determine the primary metabolites and volatile compounds. Sensory evaluation results showed that the panelists were more concerned about 'mouth feel' and 'aroma' than about 'fruit size', 'fruit shape' and 'peel color'. In total, 20 primary metabolites and 100 volatiles were detected in the pear fruit. Hexanal, (E)-2-hexenal, nonanal, d-limonene, (Z)-3-hexen-1-yl acetate and hexyl acetate were identified as the major volatile compounds. Correlation analysis revealed that l-(+)-tartaric acid, hexanoic acid, trans-limonene oxide and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate were negatively correlated with sensory scores. Furthermore, OPLS-DA results indicated that the fruit from three orchards with lower ranks in quality could be distinguished from other samples based on the contents of l-(+)-tartaric acid and other eight metabolites, which were all associated with 'mouth feel' and 'aroma'. This study reveals the metabolites that might be closely associated with the sensory quality attributes of Korla pear, which may provide some clues for promoting the fruit quality in actual production.


Asunto(s)
Frutas/química , Odorantes/análisis , Extractos Vegetales/análisis , Pyrus/química , Compuestos Orgánicos Volátiles/análisis , China , Cromatografía de Gases y Espectrometría de Masas , Humanos
14.
Molecules ; 25(18)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957552

RESUMEN

The purpose of this study is to explore the effect of 10% carbon dioxide (CO2) on the fruit quality and sugar metabolism of fresh-cut pear during storage. The results indicated that carbon dioxide treatment maintained fruit quality by delaying the decline of firmness and promoting the accumulation of total soluble solids (TSS). Moreover, carbon dioxide enhanced activities of sucrose synthase (SS), and sucrose phosphate synthase (SPS). The activities of amylase, acid invertase (AI), neutral invertase (NI), SS-cleavage, fructokinase (FK), hexokinase (HK), sorbitol oxidase (SOX), NAD-dependent sorbitol dehydrogenase (NAD-SDH), and NADP-SDH in CO2-treated fruit were inhibited. Expression levels of key genes were found to correspond with the related enzyme activities. As a result, the accumulation of glucose, fructose, sorbitol, and sucrose were accelerated by CO2, which were 12.58%, 13.86%, 24.7%, and 13.9% higher than those of the control at the end of storage, respectively. The results showed that CO2 could maintain the quality of fresh-cut pears by regulating the conversion of various sugar components to enhance soluble sugars content.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Frutas/química , Pyrus/química , Carbohidratos/química , Activación Enzimática , Enzimas/metabolismo , Calidad de los Alimentos , Frutas/metabolismo , Expresión Génica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pyrus/metabolismo , Solubilidad
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 236: 118357, 2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32375074

RESUMEN

Existing approaches for the screening of unsafe materials in food matrices are time-consuming, tiresome and destructive in nature. Therefore, in the current study, a surface-enhanced Raman spectroscopy (SERS) method based on octanethiol-functionalized core-shell nanoparticles (Oct/Au@AgNPs) was established for rapid detection of ziram in apple and pear fruits. The morphology of substrate was evaluated using high-resolution TEM images and superimposed HAADF-STEM-EDS elemental mapping images, which confirmed that Au@AgNPs having gold (Au) core size of 28 nm in diameter and silver (Ag) shell of 5.5 nm in thickness were successfully grafted with octanethiol. The SERS method with the sensitive nanoparticles could detect ziram of up to 0.015 and 0.016 ppm in apple and pear with high coefficients of determination (R2) of 0.9987 and 0.9993, respectively. Furthermore, satisfactory recoveries (80-106%) were also accomplished for the fungicide in real samples. This work demonstrated that the functionalized silver-coated gold nanoparticles were easy to prepare and could be used as sensitive SERS platforms for monitoring of other agrochemicals in foods.


Asunto(s)
Malus/química , Nanopartículas del Metal/química , Pyrus/química , Espectrometría Raman/métodos , Ziram/análisis , Contaminación de Alimentos/análisis , Frutas/química , Fungicidas Industriales/análisis , Oro/química , Límite de Detección , Microscopía Electrónica de Transmisión , Extractos Vegetales/análisis , Extractos Vegetales/química , Sensibilidad y Especificidad , Plata/química , Espectrometría por Rayos X
16.
Int J Biol Macromol ; 157: 444-451, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32335112

RESUMEN

Two neutral polysaccharides (PSNP-1, 104.7 kDa; PSNP-2, 24.5 kDa) were isolated from the pulp of Pyrus sinkiangensis Yu. by using the combined techniques of ion-exchange and gel permeation chromatography. According to the IR, NMR spectra, monosaccharide composition, and methylation analyses, PSNP-1 was mainly composed of glucose and xylose residues, which form a typical xyloglucan. PSNP-2 contained an arabinan region composed of 1,5-linked Araf residues, a xyloglucan region that was mainly composed of t-, 1,2-linked Xylp, and 1,4-, 1,4,6-linked Glcp residues. PSNP-1 and PSNP-2 could stimulate the cell viability, NO release, and cytokine secretion (IL-6 and TNF-α) of RAW264.7 macrophages at the adosage of 250 µg/mL. It was suggested that PSNP-1 and PSNP-2 may increase macrophage-mediated immunostimulatory activity.


Asunto(s)
Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Pyrus/química , Animales , Supervivencia Celular/efectos de los fármacos , Citocinas/biosíntesis , Factores Inmunológicos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Metilación , Ratones , Estructura Molecular , Peso Molecular , Óxido Nítrico , Extractos Vegetales/aislamiento & purificación , Polisacáridos/aislamiento & purificación , Células RAW 264.7 , Relación Estructura-Actividad
17.
J Agric Food Chem ; 68(8): 2493-2505, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-31976665

RESUMEN

Lignin content, composition, and linkage types were investigated in pear fruit cultivars and related species. Lignin content increased during early stages and then decreased toward ripening in the core and flesh of "Gold Nijisseiki" and "Alexandrine Douillard". The lignin content was highest at harvest in Chinese quince. Only trace amounts of lignin were detected in apple flesh. The lignin content was low in Japanese pears "Ohshu", "Hosui", and "Kosui", and the noncondensed lignin index was high in flesh. The lignin type was guaiacyl-syringyl (GS) in these pears and related species. The S/G ratio at harvest varied widely (0.75-2.64) and increased during early stages and remained constant toward harvest in "Gold Nijisseiki" and "Alexandrine Douillard". "Gold Nijisseiki" and "Alexandrine Douillard" were determined to be G- and S-lignin-rich types, respectively. ß-Aryl ether, phenylcoumaran, and resinol interunit linkage types were detected among monolignol bonds, and ß-Aryl ether units were the main linkages in the pear.


Asunto(s)
Lignina/química , Extractos Vegetales/química , Pyrus/química , Frutas/química , Frutas/clasificación , Estructura Molecular , Pyrus/clasificación
18.
Int J Biol Macromol ; 142: 232-236, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31669276

RESUMEN

The antioxidant activities of polysaccharide from balsam pear were studied. It was determined by gel permeation chromatography that the molecular weight distribution of purified polysaccharide was concentrated near 33582 Da. It indicated that the monosaccharide components were rhamnose, galacturonic acid, galactose, xylose and arabinose. Fourier transform infrared spectroscopy, nuclear magnetic resonance and Congo red experiments showed that there are C1, C2, C3, C5 links, and stable ß-triple helix conformation in aqueous solution. It was found that polysaccharide had good scavenging effect on free radicals. So, balsam pear polysaccharide should be a potential antioxidant.


Asunto(s)
Antioxidantes/farmacología , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Pyrus/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Fraccionamiento Químico , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Conformación Molecular , Peso Molecular , Monosacáridos/análisis , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Análisis Espectral
19.
Food Chem ; 299: 125114, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31326758

RESUMEN

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.


Asunto(s)
Antioxidantes/análisis , Frutas/química , Fenoles/análisis , Pyrus/química , Antioxidantes/química , Cromatografía Liquida , Hidrólisis , Fenoles/química , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
20.
J Sci Food Agric ; 99(14): 6380-6391, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31283026

RESUMEN

BACKGROUND: Prickly pears are potential candidates for the development of low-cost functional foods because they grow with low water requirements in arid regions of the world. They are sources of betalains and phenolic compounds, which have been reported to contribute to human health. The study of the biological activity of different varieties and of their isolated bioactive constitutes is fundamental in the design of functional foods. In this context, our objective is the assessment of the ability of Spanish and Mexican prickly-pear cultivars to inhibit enzymes related to type 2 diabetes and the inflammatory response, and the contribution of their bioactive compounds to their nutra-pharmaceutical potential. RESULTS: Prickly pear peels presented the highest antioxidant activity due to their high isorhamnetin glycoside content. Isorhamnetin glycosides showed significantly higher antioxidant and anti-inflammatory activity than aglycone, particularly isorhamnetin glucosyl-rhamnosyl-pentoside (IG2), which also reported antihyperglycemic activity. Morada, Vigor, and Sanguinos whole fruits exhibited moderate α-amylase inhibition and higher α-glucosidase inhibition, which is ideal for lowering glucose absorption in hyperglycemia management. Sanguinos peels presented the highest anti-inflammatory activity because of their high indicaxanthin content and isorhamnetin glycoside profile. CONCLUSIONS: In the design of prickly pear functional foods, technological processing should prioritize the retention or concentration of these bioactive compounds to preserve (or increase) their natural antioxidant, antihyperglycemic and anti-inflammatory activity. Peels of red and orange varieties should be further evaluated for antioxidant and anti-inflammatory purposes while whole fruits of red and purple varieties could be considered possible candidates for hyperglycemia management. © 2019 Society of Chemical Industry.


Asunto(s)
Antiinflamatorios/química , Diabetes Mellitus Tipo 2/enzimología , Inhibidores Enzimáticos/química , Hipoglucemiantes/química , Extractos Vegetales/química , Pyrus/química , Antioxidantes/química , Betalaínas/química , Diabetes Mellitus Tipo 2/metabolismo , Frutas/química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Cinética , Fenoles/química , Pyrus/clasificación , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/química , alfa-Amilasas/metabolismo , alfa-Glucosidasas/química , alfa-Glucosidasas/metabolismo
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