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1.
Food Chem ; 302: 125141, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416000

RESUMO

Four jams were made using two wild species of Physalis spp., two containing seeds (P1WS and P2WS) and two without seeds (P1WHS and P2WHS). Physicochemical, nutraceutical and rheological properties of the jams were determined and a sensory evaluation made. P1WS and P2WS jams had lower carbohydrates contents, reducing sugars and calories, and higher fiber contents than P1WHS and P2WHS. The presence of seeds in the jams increased phenols and flavonoids. However, the seedless jams had better sensory acceptance. The dynamic rheological testing indicated a gel-like behavior (G'>G'') in whole jams. Also, shearing flow testing showed shear-thinning and thixotropic behaviors, which are shared characteristics with others fruit jams, such as mango or gabiroba. The presence of seeds in the jam affected directly yield stress, apparent viscosity, hysteresis area, and viscoelastic parameters, which were described in the sensory analysis as a "less desirable texture". The use of seeds from wild species of Physalis spp., increased the nutritional value of jam. However, it would be necessary to improve consumer acceptance through technological processes prior to marketing.


Assuntos
Suplementos Nutricionais/análise , Manipulação de Alimentos , Frutas/química , Physalis/química , Reologia , Sementes/química , Paladar , Fibras na Dieta/análise , Flavonoides/análise , Valor Nutritivo , Fenóis/análise , Viscosidade
2.
Food Chem ; 302: 125288, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419774

RESUMO

The effects of benzothiadiazole (BTH) on Penicillium expansum development, mitochondria energy metabolism, and changes in the number and structure of mitochondria in apple fruit were investigated after the fruit were immersed in 100 mg L-1 BTH for 10 min and then stored at 22 °C. The results indicated that BTH treatment significantly decreased the lesion diameter of fruit challenged with P. expansum; further, treatment enhanced the activities of mitochondrial respiratory metabolism-related enzymes, such as succinate dehydrogenase, cytochrome oxidase, H+-ATPase and Ca2+-ATPase, along with high ATP level and energy status in apple fruit during storage. Moreover, transmission electron microscopy results indicated that BTH treatment was beneficial for maintaining the number and structure of mitochondria during storage. The results suggested that BTH treatment enhanced ATP levels via mitochondrial energy metabolism, which might contribute to the induced resistance in apple fruit during storage.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Armazenamento de Alimentos , Frutas/metabolismo , Malus/efeitos dos fármacos , Malus/metabolismo , Mitocôndrias/efeitos dos fármacos , Tiadiazóis/farmacologia , Frutas/microbiologia , Malus/microbiologia , Mitocôndrias/metabolismo , Penicillium/fisiologia
3.
Food Chem ; 302: 125308, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401419

RESUMO

Fruit peelings are increasingly being used as ingredients for the formulation of functional foods. In this study, the antioxidant activity and browning behaviour of free and bound phenolic fractions of mango, apple, orange and banana peelings microwave-blanched at 720 W for 1, 3 and 5 min were determined. The fractions were equally analyzed for their phenolic content and composition. Generally, increased microwave blanching was accompanied by a significant increase of total phenolics content in free and bound fractions. Increased antioxidant activities at 3 and 5 min of blanching varied with the type of fruit peelings. Browning rates decreased with microwave blanching time except in the case of apple peelings. Epicatechin, ferulic acid, caffeic acid, rosmarinic acid, p-coumaric acid and gallic acid were identified in fruit peelings. Generally, microwave blanching for 3 or 5 min was found to preserve antioxidant activities and reduce the browning rate.


Assuntos
Antioxidantes/química , Frutas/química , Fenóis/química , Indústria de Processamento de Alimentos/métodos , Micro-Ondas , Fenóis/análise , Fatores de Tempo
4.
Waste Manag ; 101: 161-170, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610477

RESUMO

Food losses and waste are a global problem, with an estimated 1.3 billion tons lost annually. In Brazil, fruit and vegetable losses amount to approximately 30% and occur in the processing, handling and storage stages. Thus, this study aimed to evaluate the post-harvest losses of fruits and vegetables in the Central Supply (CEASA) of Salvador, Brazil, its determinants and potential solutions to minimize the problem. A cross-sectional, descriptive and quantitative study was carried out in which data were collected by observing the operation of the supply units, registration in a field notebook, and administering a questionnaire to sellers that covered four main dimensions: socioeconomic profile of vendors; hygienic-sanitary conditions; characteristics of acquisition, storage and commercialization of products; and measures used by sellers to reduce losses. Many inadequacies were found, including the transportation and reception of products and their commercialization. Regarding hygiene, there were flaws in the care of the environment, the products and the food handlers. At most sites (75%), there were problems with infrastructure. The loss was estimated to be on the order of 9.5 tonnes/week, especially bananas, papayas, tomatoes, peppers and lettuce. The main causes of loss were exceeding volume in purchases, storage without refrigeration and careless handling by consumers and vendors. Strategies to reduce losses included price reduction, donation practices and consumption by sellers. The study indicates the need for improvements both in the infrastructure and in the hygienic care, management and post-harvest conservation of the fruits and vegetables.


Assuntos
Frutas , Verduras , Brasil , Comércio , Estudos Transversais , Abastecimento de Alimentos
5.
Food Chem ; 304: 125383, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479997

RESUMO

An aqueous two-phase system was used in conjunction with ultrasonic cell disruption to extract and separate solanine (mainly solasonine and solamargine) and Solanum nigrum polysaccharide from Solanum nigrum unripe fruit. The optimized conditions of the present study were determined by a single-factor experiment and a multifactor experiment. The concentration of ethanol was set at 60% and the duration of the ultrasonic cell disruption extraction was 50 min. In the ethanol-K2CO3 aqueous two-phase separation system, the concentration of ethanol was 36%, the concentration of K2CO3 was 0.21 mg·mL-1, and the temperature was 15 °C. The solasonine and solamargine were determined by high-performance liquid chromatography, and the Solanum nigrum polysaccharide was determined by an ultraviolet-visible spectrophotometer in accordance with the phenol-sulfuric acid method. xUnder optimized conditions, the average extraction efficiencies of solasonine, solamargine and Solanum nigrum polysaccharide were 95.86%, 95.95% and 96.95%, respectively, and the average separation efficiencies of solasonine, solamargine and Solanum nigrum polysaccharide were 2.07 mg·g-1, 2.05 mg·g-1 and 8.15 mg·g-1, respectively.


Assuntos
Frutas/química , Polissacarídeos/isolamento & purificação , Solanina/análise , Solanum nigrum/química , Ultrassom , Cromatografia Líquida de Alta Pressão , Polissacarídeos/análise , Alcaloides de Solanáceas/análise , Alcaloides de Solanáceas/isolamento & purificação , Espectrofotometria
6.
Food Chem ; 302: 125366, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442705

RESUMO

Sambucus nigra is one of the richest sources of anthocyanins and other polyphenols being used industrially as a source of antioxidants, colorants, and bioactives. Although cultivars can influence elderberry composition, no study has addressed the effect of harvesting year on elderberries composition and bioactivity. The composition of the main Portuguese cultivars, "Sabugueiro", "Sabugueira" and "Bastardeira", were evaluated during three consecutive years. Harvesting year had a stronger influence on the chemical composition than cultivars, including total sugars, anthocyanins, and phenolic compounds, being related to the different climatic conditions, especially water status. "Bastardeira" was the best cultivar concerning total soluble solids, anthocyanins, polyphenols, and antioxidant activity, but containing a lower total free sugar content compared to "Sabugueiro". The results obtained in this study provide novel information from a nutritional perspective and for breeding programs aiming to select cultivars with enhanced levels of health-promoting compounds or for other industrial applications of elderberries.


Assuntos
Antocianinas/análise , Frutas/química , Fenóis/análise , Sambucus/química , Agricultura , Antioxidantes/análise , Ácido Oleanólico/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Polifenóis/análise , Portugal , Sambucus nigra/química , Especificidade da Espécie , Triterpenos/análise
7.
Food Chem ; 302: 125373, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442706

RESUMO

The aim of this work was to investigate and compare the phenolic profile of 15 wild growing blackthorn (Prunus spinosa L.) genotypes from the slopes of Fruska Gora mountain in north Serbia. Their effect in inhibiting i) α-amylase and α-glucosidase activities and ii) colorectal cancer cell line (HT29) growth was also studied. Blackthorn fruit extracts exhibited high phenolic content being enrich in anthocyanins. Principal component analysis was used to correlate the bioactive response with phenolic composition. It was found that derivatives quercetin and anthocyanin peonidin are the major contributors of the inhibition of carbohydrates hydrolyzing enzymes as well as with the antiproliferative effect of blackthorn. Among all samples, the genotype from Beska locality showed the higher capacity in inhibiting alpha-amylase, alpha-glucosidase and HT29 cell growth. Because of high anthocyanin content and higher bioactive response, these genotypes could be recommended for the further cultivation and investigation.


Assuntos
Polifenóis/análise , Prunus/química , Prunus/genética , Antocianinas/análise , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Genótipo , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Células HT29 , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Análise de Componente Principal , Quercetina/análise , Ácido Quínico/análogos & derivados , Ácido Quínico/análise , Sérvia , alfa-Amilases/antagonistas & inibidores
8.
Food Chem ; 303: 125396, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446365

RESUMO

This study describes the determination of lead at trace levels by slotted quartz tube flame atomic absorption spectrophotometry (SQT-FAAS) after preconcentration by the help of stearic acid coated magnetic nanoparticle (SAC-MNPs) based sonication assisted dispersive solid phase extraction (SA-DSPE). SAC-MNPs were used due to their easy separation advantages by the application of external magnetic field. All extraction parameters were optimized by response surface methodology based experimental design. The experimented data was evaluated by the analysis of variance. Under the optimum conditions, about 31 folds enhancement in detection power was obtained over the conventional FAAS. The recovery results obtained for samples spiked at 60 and 120 ng mL-1 were 106.6 and 102.6%, respectively, validating the method as accurate and applicable to the red pepper matrix. The percent relative standard deviations of the results were under 5.0% even at low concentrations that established high precision for replicate extractions and instrumental readings.


Assuntos
Capsicum/química , Chumbo/análise , Chumbo/isolamento & purificação , Microextração em Fase Líquida/métodos , Magnetismo/métodos , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Contaminação de Alimentos/análise , Frutas/química , Magnetismo/instrumentação , Nanopartículas de Magnetita/química , Quartzo/química , Sensibilidade e Especificidade , Sonicação , Ácidos Esteáricos/química
9.
Food Chem ; 303: 125400, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470275

RESUMO

Siraitia grosvenorii fruit (SGF) has been used as a natural sweetener and traditional medicine in China for more than two centuries. This study evaluated the effect of SGF extract supplementation (0.5%, 1%, and 2%) on the chemical, microbial and sensory properties of probiotic yogurt. The antioxidant, angiotensin-converting-enzyme inhibitory (ACE-I) and antibacterial bioactivities were determined. SGF extract supplementation improved some of the chemical and physicochemical characteristics. Probiotic yogurt with the fruit extract had significantly more Lactobacillus casei and Lactobacillus bulgaricus, whereas there was no significant effect on the number of Streptococcus thermophiles. The bioactivities were significantly increased by SGF extract supplementation. Probiotic yogurt with 2% SGF extract showed the highest antioxidant, ACE-I, and antibacterial activities, whereas the one with 1% SGF extract conferred the highest sensory attributes score. Overall, SGF extract offers a promising option as a dietary supplement to produce novel dairy products that have high nutritional and bioactivity values.


Assuntos
Cucurbitaceae/química , Aditivos Alimentares/análise , Extratos Vegetais/análise , Probióticos/análise , Iogurte/microbiologia , Inibidores da Enzima Conversora de Angiotensina/análise , Antioxidantes/análise , China , Frutas/efeitos dos fármacos , Humanos , Lactobacillus casei/genética , Lactobacillus casei/crescimento & desenvolvimento , Lactobacillus casei/isolamento & purificação , Lactobacillus delbrueckii/genética , Lactobacillus delbrueckii/crescimento & desenvolvimento , Lactobacillus delbrueckii/isolamento & purificação , Peptidil Dipeptidase A/química , Paladar , Iogurte/análise
10.
Food Chem ; 303: 125424, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472384

RESUMO

The aim of our study was to investigate the effect of drop shock on physiological responses and genes expression in harvested apple fruit stored at 20 ±â€¯2 °C. Ethylene production, respiratory rate, firmness, soluble solid content, relative electrical conductivity, LOX (lipoxygenase) activity, MDA (malondialdehyde) content, variation of volatile compounds, ethylene biosynthetic genes, and ethylene receptor genes of apple fruit were examined. The results indicated that drop shock observably resulted in the increase of ethylene production, respiratory rate, soluble solid content, relative electrical conductivity, LOX activity, MDA content and gene expression levels in apples. Furthermore, drop shock significantly decreased firmness and high-intensitive drop shock stimulated the accumulation of aldehydes and esters in harvested apples. Overall, the greater impact on apple quality is the effect of larger amplitude of shock during truck transportation, which seriously reduced storage life and quality of postharvest apples.


Assuntos
Frutas/química , Malus/genética , Proteínas de Plantas/genética , Aldeídos/metabolismo , Fenômenos Biomecânicos , Ésteres/metabolismo , Etilenos/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Lipoxigenase/genética , Lipoxigenase/metabolismo , Malondialdeído/metabolismo , Malus/química , Malus/metabolismo , Proteínas de Plantas/metabolismo , Controle de Qualidade
11.
Food Chem ; 303: 125385, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442899

RESUMO

In this study, the mechanism activated by melatonin treatment at 100 µM for maintaining nutraceutical properties in pomegranate fruits during storage at 4 °C for 120 days was investigated. Our results showed that the higher G6PDH and 6PGDH activities in pomegranate fruits treated with melatonin may be responsible for sufficient supply of intracellular NADPH. Also, higher AA and GSH accumulation in pomegranate fruits treated with melatonin may ascribe to higher APX and GR activities coincided with lower AAO activity. In addition, pomegranate fruits treated with melatonin exhibited significantly higher PAL activity resulting in higher phenols and anthocyanins accumulation as well as higher DPPH scavenging capacity. Additionally, higher AOX gene expression in pomegranate fruits treated with melatonin may be beneficial for ROS scavenging molecules accumulation. Therefore, maintaining nutraceutical properties of pomegranate fruits treated with melatonin may ascribe to sufficient intracellular NADPH supply by promoting G6PDH and 6PGDH activities during cold storage.


Assuntos
Antocianinas/análise , Conservação de Alimentos , Melatonina/farmacologia , Punicaceae/efeitos dos fármacos , Suplementos Nutricionais/análise , Frutas/química , Frutas/efeitos dos fármacos , Punicaceae/química
12.
Food Chem ; 303: 125387, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454759

RESUMO

In the study, the impact of harvest time on total phenolic content, antioxidant activity, and phenolic compounds of prickly pear (Opuntia ficus-barbarica A. Berger) fruit pulp and the oil content and fatty acids profile of the seed were investigated. The highest total phenolic content was determined as 156.77 mg/100 g in July 1 harvest, while the maximum antioxidant activity and total oil content were found as 9.81% and 6.80% at the last stage of maturation (15 August), respectively. The highest oleic (28.51%), palmitic (22.61%) and stearic acid contents (9.20%) in seed oil were observed in June 15 harvest. The highest value for linoleic acid (57.50%) was detected in August 15 harvest. Prickly pear is a vital source of bioactive constituents such as phenolic and antioxidant substances in terms of being useful for human health and the optimum harvesting time to retain high quantities of most phenolic compounds is 1st July.


Assuntos
Antioxidantes/análise , Ácidos Graxos/análise , Frutas/química , Opuntia/química , Fenóis/análise , Estações do Ano , Frutas/metabolismo , Opuntia/metabolismo , Sementes/química
13.
Food Chem ; 303: 125386, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473454

RESUMO

The present work investigated the influences of ultrahigh pressure (UHP), ultrasound (US) and their combination (UHP-US) as pretreatments on properties of vacuum-freeze dried strawberry slices. During vacuum-freeze drying, drying duration and total energy consumption of UHP sample, US sample and UHP-US sample was decreased. After the UHP or US pretreatments, a* value (redness), antioxidative substances (total anthocyanin content, total flavonoid content, total phenolic content, diphenyl picrylhydrazyl (DPPH), hydroxyl (-OH) radical-scavenging assay), hardness and cross-section areas of matrix in the dried slices were significantly (P < 0.05) increased. Transverse relaxation times and peak area corresponding to free water in the pretreated samples were obviously decreased, indicating lower mobility in the pretreated samples. As compared with UHP or US individually, UHP in combination with US increased those parameters more pronouncedly. Therefore, UHP and US are promising techniques for the vacuum-freeze drying processing of strawberry products.


Assuntos
Dessecação , Conservação de Alimentos/métodos , Fragaria/química , Frutas/química , Pressão , Ondas Ultrassônicas , Antocianinas/análise , Antioxidantes/análise , Antioxidantes/química , Cor , Flavonoides/análise , Liofilização , Frutas/efeitos da radiação , Fenóis/análise , Vácuo
14.
Food Chem ; 303: 125346, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446364

RESUMO

The effect of a respiratory quotient dynamic controlled atmosphere (DCA - RQ), which induces ethanol production through low oxygen storage, and ethanol application on softening of Braeburn apples stored at different temperatures was investigated. DCA - RQ storage was associated with the activation of the alcohol dehydrogenase (ADH) and greater anaerobic metabolism in comparison with DCA - CF (chlorophyll fluorescence) and controlled atmosphere (CA) storage. Greater anaerobic metabolism resulted in lower ethylene production, ACC oxidase activity, membrane permeability, -galactosidase activity and, therefore, less softening after long-term storage. Ethanol application after CA storage decreased ethylene biosynthesis, respiration rate and membrane permeability. Storage at 3 °C resulted in the lowest soluble solids and acidity, but not softening. In conclusion, Braeburn apples could be stored at 3 °C under DCA - RQ1.5. Additionally, ethanol produced by the fruit, or applied externally, had a significant effect on inhibiting softening during and after storage.


Assuntos
Atmosfera , Etanol/farmacologia , Malus/efeitos dos fármacos , Malus/metabolismo , Oxigênio/metabolismo , Anaerobiose/efeitos dos fármacos , Frutas/efeitos dos fármacos , Frutas/metabolismo
15.
Food Chem ; 302: 125337, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419770

RESUMO

The composition of volatile compounds in Korla fragrant pears was determined using headspace solid-phase microextraction followed by a gas chromatography-mass spectrometry analysis using fruits at 30, 90, and 150 days after bloom. Hexanal, (E)-2-hexenal, 1-hexanol, (E)-2-hexen-1-ol, (Z)-3-hexen-1-ol, and hexyl acetate were identified as the major compounds. The composition of volatile compounds was associated with fatty acid concentrations and key enzyme activity in the lipoxygenase pathway. In vitro linoleic and linolenic acid feeding experiments conducted using cubes of fruit flesh demonstrated that the concentrations of volatile esters, such as hexyl acetate, in the treated fruits increased significantly after incubation for 12 h compared with those in the control fruits, which was accompanied by a reduction in aldehyde and alcohol concentrations (p < 0.05 or p < 0.01). However, the treatments did not significantly influence the enzyme activity and expression of genes encoding the enzymes.


Assuntos
Frutas/química , Odorantes/análise , Pyrus/química , Pyrus/fisiologia , Compostos Orgânicos Voláteis/análise , Aldeídos/análise , Ésteres/análise , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Análise de Alimentos/métodos , Frutas/efeitos dos fármacos , Frutas/fisiologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Regulação da Expressão Gênica de Plantas , Hexanóis/análise , Ácido Linoleico/farmacologia , Pyrus/efeitos dos fármacos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/metabolismo , Ácido alfa-Linoleico/farmacologia
16.
J Photochem Photobiol B ; 201: 111639, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31698220

RESUMO

Increasing concerns about health safety, social impacts and fair trade have intensified the industrial interest for using natural products in commercial cosmetic formulations. Several studies are currently focusing on plant extracts, but tropical fruits, such as guava, remain yet unexplored and, consequently, underutilized. This research aims to evaluate the potential for using guava-fruit extract as a photoprotective additive agent for sun cream formulations. The phytochemical screening revealed the presence of flavonoids and tannins and the absence of coumarins. Although the Psidium guajava extract showed a low sun protection factor (SPF) value (1.0), it improved in about 134% the photoprotective result (8.1) of 7.5% 2-ethyl-hexyl methoxycinnamate formulation. Therefore, guava-fruit extract supplementation in the formulation shows the potential to reduce the use of synthetic photoprotectors in about 78.9% from the total synthetic organic filters used to achieve the SPF value of 18. Thus, sun cream supplemented with guava-fruit extract show the potential for minimizing the risk of synthetic agent toxicity, and a 65.8% reduction in the cost of the sunscreen production.


Assuntos
Extratos Vegetais/química , Psidium/química , Protetores Solares/química , Raios Ultravioleta , Composição de Medicamentos , Frutas/química , Frutas/metabolismo , Psidium/metabolismo , Espectrofotometria , Fator de Proteção Solar
17.
J Photochem Photobiol B ; 201: 111649, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710925

RESUMO

In the present systematic study, silver nanoparticles have been synthesized using the fruits of Alpinia nigra. Apart from the presence of saponins, glycosides, alkaloids, steroids, the extract of A. nigra fruits are rich in polyphenols. The Total Flavonoid and Phenol Content of A. nigra fruits extract is 718 mgRE/g extract and 74.9 mgGAE/g extract respectively. The formation of the nanoparticles was validated through characterization techniques like UV-Vis spectroscopy, X- ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Energy dispersive X-ray spectroscopy (EDX). The spherical shape of silver nanoparticles is observed in Transmission Electron Microscopy (TEM) images. The average particle size of the silver nanoparticles is 6 nm. The biomolecules of the fruit extract played the dual role of reducing and capping agents which is evident from Fourier Transform Infrared (FTIR) spectrometer and Scanning Electron Microscopy (SEM) image analysis. The A. nigra capped silver nanoparticles exhibited promising antimicrobial activity against gram negative bacteria Klebsiella pneumoniae, gram positive bacteria Staphylococcus aureus and the pathogenic fungus, Candida albicans. Amongst the three pathogens, Klebsiella pneumoniae is the most susceptible to silver nanoparticles. Furthermore, the nanoparticles efficiently catalysed the degradation of the anthropogenic dyes Methyl orange, Rhodamine B and Orange G in the presence of sunlight. The photocatalytic degradation process follows the pseudo-first order kinetics. These results confirm that the silver nanoparticles can be efficiently synthesized via a green route using A. nigra fruits with applications as antimicrobial and catalytic agents.


Assuntos
Alpinia/química , Anti-Infecciosos/síntese química , Nanopartículas Metálicas/química , Prata/química , Alpinia/metabolismo , Anti-Infecciosos/farmacologia , Compostos Azo/química , Catálise , Corantes/química , Frutas/química , Frutas/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Luz Solar
18.
J Agric Food Chem ; 67(46): 12972-12985, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31709797

RESUMO

Controlling the temperature inside a greenhouse during the summer is a problem of increasing importance in the Mediterranean countries, especially in the Spanish southeast. The metabolic profile of greenhouse tomatoes and leaves grown under conventional conditions and within the presence of a shade mesh (∼50% reduction of sunlight radiation) has been monitored. Tomatoes were weekly harvested from May to July 2017 and analyzed by NMR spectroscopy coupled to multivariate data analysis techniques, together with oxygen radical absorbance capacity (ORAC) assays (for antioxidant activity). Fatty acids and carotenoids profiles were unraveled by GC-FID and HPLC-DAD, respectively. To verify whether it would be possible to take advantage of different light growing conditions to potentiate a plant's defense system, leaves of the corresponding plants were collected and their methanolic extracts were analyzed by NMR toward deciphering new biomarkers, which were used to assess their antibacterial and antibiofilm activities. The presence of a shading mesh resulted in a reduction in tomato production and in smaller fruits with lower contents of sugars (glucose and fructose) and carotenoids (lycopene and ß-carotene) and higher contents of organic acids, amino acids, and polyunsaturated fatty acids (linoleic and oleic acids) and of phenylpropanoids and flavonoids (which contributed to an increased antioxidant activity). Methanolic extracts of leaves of nonshaded plants showed a higher antibiofilm activity than that from shaded plants. This activity was well-correlated with an increase of phenolic compounds, together with some specific amino acids and organic acids from tomato leaves.


Assuntos
Frutas/química , Lycopersicon esculentum/efeitos da radiação , Folhas de Planta/química , Antioxidantes/metabolismo , Alimentos Orgânicos/análise , Alimentos Orgânicos/efeitos da radiação , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/efeitos da radiação , Lycopersicon esculentum/química , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Espectroscopia de Ressonância Magnética , Metaboloma/efeitos da radiação , Metabolômica , Valor Nutritivo/efeitos da radiação , Extratos Vegetais/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Luz Solar
19.
Zootaxa ; 4624(1): zootaxa.4624.1.5, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31716237

RESUMO

The immatures and adults of the jujube tube spittlebug, Machaerota planitiae Distant (Hemiptera: Cercopoidea: Machaerotidae) are described and illustrated. A key to nymphal instars is included. Recently introduced to Bangladesh, most likely from adjacent South and Southeast Asian countries, this species has become a serious pest of jujube (Ziziphus jujuba Mill., Rhamnaceae) causing severe damages to jujube production in Bangladesh.


Assuntos
Hemípteros , Ziziphus , Animais , Bangladesh , Frutas
20.
Zootaxa ; 4638(2): zootaxa.4638.2.6, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31712478

RESUMO

A new species of the lace bug genus Physatocheila Fieber, 1844 (Hemiptera: Heteroptera: Tingidae), is described from eastern Honshu, Japan under the name of P. nigrintegerrima. A photograph of a living individual is also given. This species is found on the fruits of Hovenia dulcis Thunb. (Rhamnaceae) and is the first documented fruit-feeder of the genus. A key to the species of the genus from Japan is provided.


Assuntos
Hemípteros , Heterópteros , Distribuição Animal , Animais , Frutas , Japão
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