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1.
Food Chem ; 337: 127751, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777575

RESUMO

The type of container (airtight and pouches with different O2 permeability) and packing conditions (cover brine, air or N2 atmosphere) has been studied to preserve black ripe olives in acid medium for a year. Unlike the traditional sterilized product, these acidified olives only needed pasteurization to assure its microbial safety, the absence of acrylamide being an additional advantage. Surprisingly, an increase in the oxygen diffusion through the films (i) faded the black color of the olives, (ii) softened the fruit that lost around 33% of its initial firmness in only 6 months, and (iii) produced the lipid́s oxidation forming volatile compounds that transmitted an abnormal flavor which tasters identified as rancid. Therefore, ripe olives in acid medium must be packed in airtight containers such as glass jars, cans o metallic pouches with cover brine or N2 atmosphere. The addition of calcium is recommended to avoid olive softening.


Assuntos
Embalagem de Alimentos/métodos , Olea/química , Acrilamida/análise , Cor , Frutas/química , Concentração de Íons de Hidrogênio , Fenômenos Mecânicos , Oxirredução , Pasteurização , Paladar
2.
J Oleo Sci ; 69(9): 973-984, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788511

RESUMO

China has taken olive cultivation as a significant part of its agricultural development. Longnan city of Gansu province was marked into the world olive distribution map by International Olive Oil Council in 1998. However, so far, little research has been done on the growth and development stages of Chinese olives. The objective of this study was to investigate the dynamics changes of several quality characteristics of olive oil at different sampling times. Olive fruit of 'Chenggu-32' grown in Longnan were harvested at twenty-four time periods and used for determination of phenotypic traits and oil quality characteristics: total polyphenols and flavonoids contents, as well as fatty acid composition by using Gas Chromatography-Mass Spectrometer (GC-MS) and analysed by using Principal Components Analysis (PCA). Towards maturation, fruit moisture content decreased while oil content increased. Levels of both total flavonoids and total polyphenols contents slightly decreased first then increased. The ratio of unsaturated to saturated fatty acids was close to three. The ratio of monounsaturated fatty acids (MUFA)/ polyunsaturated fatty acids (PUFA) was from 2.28 to 4.05. The oleic acid (C18:1)/linoleic acid (C18:2) ratio was varied between 5.23 and 10.67 according to different sampling dates. The olive oil had lower oleic acid (C18:1) levels, higher linoleic acid (C18:2), linolenic acid (C18:3), and palmitic acid (C16:0) levels compared to Codex values (2017) in some periods, which is the characteristics fatty acid composition of 'Chenggu-32' variety in Longnan, China.


Assuntos
Olea/química , Olea/genética , Azeite de Oliva/análise , Fenótipo , China , Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Insaturados/análise , Flavonoides/análise , Análise de Alimentos , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/análise , Olea/classificação , Ácido Oleico/análise , Ácido Palmítico/análise , Polifenóis/análise
3.
PLoS One ; 15(7): e0232811, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614852

RESUMO

In the present work, the olive mill solid waste (OMSW)-derived biochar (BC) was produced at various pyrolytic temperatures (300-700°C) and characterized to investigate its potential negative versus positive application effects on pH, electrical conductivity (EC), and nutrients (P, K, Na, Ca, Mg, Fe, Mn, Zn, and Cu) availability in a calcareous loamy sand soil. Therefore, a greenhouse pot experiment with maize (Zea mays L.) was conducted using treatments consisting of a control (CK), inorganic fertilizer of NPK (INF), and 1% and 3% (w/w) of OMSW-derived BCs. The results showed that BC yield, volatile matter, functional groups, and zeta potential decreased with pyrolytic temperature, whereas BC pH, EC, and its contents of ash and fixed carbon increased with pyrolytic temperature. The changes in the BC properties with increasing pyrolytic temperatures reflected on soil pH, EC and the performance of soil nutrients availability. The BC application, especially with increasing pyrolytic temperature and/or application rate, significantly increased soil pH, EC, NH4OAc-extractable K, Na, Ca, and Mg, and ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA)-extractable Fe and Zn, while AB-DTPA-extractable Mn decreased. The application of 1% and 3% BC, respectively, increased the NH4OAc-extractable K by 2.5 and 5.2-fold for BC300, by 3.2 and 8.0-fold for BC500, and by 3.3 and 8.9-fold for BC700 compared with that of untreated soil. The results also showed significant increase in shoot content of K, Na, and Zn, while there was significant decrease in shoot content of P, Ca, Mg, and Mn. Furthermore, no significant effects were observed for maize growth as a result of BC addition. In conclusion, OMSW-derived BC can potentially have positive effects on the enhancement of soil K availability and its plant content but it reduced shoot nutrients, especially for P, Ca, Mg, and Mn; therefore, application of OMSW-derived BC to calcareous soil might be restricted.


Assuntos
Carvão Vegetal/farmacologia , Nutrientes/análise , Olea/química , Areia/química , Solo/química , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Minerais/metabolismo , Nutrientes/metabolismo , Fatores de Tempo , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
4.
J Oleo Sci ; 69(7): 719-726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612021

RESUMO

Residues of olive fruit (ROF) after the extraction of oils are an increasing source of industrial waste, because olive oil is becoming more popular as a healthy food. It has been reported that olives have some polyphenols that have an antioxidation capability. On the other hand, excess oxidative stress disrupts epidermal barrier function. This study was conducted to determine whether ROF could be utilized as an antioxidant source to reduce industrial wastes and to identify possible active materials to maintain healthy skin. Olive fruits are categorized into two groups depending on the time of harvest, young fruit (YF) and mature fruit (MF). Thus, we examined the antioxidant potentials of extracts from YF and from MF to remove reactive oxygen species (ROS) from biological and chemical aspects. HaCaT keratinocytes cultured with extracts of YF or MF had reduced levels of intracellular ROS in spite of the relatively low chemical capability against ROS scavenging. The biological effects of the YF extract were superior to those of the MF extract. The YF extract showed effective reductions of intracellular ROS and carbonylated proteins that were elevated by the stress-related hormone cortisol. In addition, the YF extract reinforced the intracellular antioxidation capability through the activation of Nrf2 signaling. Taken together, the YF extract was an effective source to reinforce the intracellular antioxidation capability. We conclude from these results that utilizing ROF would lead to the reduction of industrial wastes and would supply active materials to maintain healthy skin.


Assuntos
Queratinócitos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Olea/química , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Antioxidantes , Células Cultivadas , Humanos , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
5.
Food Chem ; 329: 127153, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512392

RESUMO

Olive leaves are an under valorized residue of olive tree pruning and olive fruit harvesting and that are usually removed by either burning or grinding and scattering them on fields. However, as plant material easily available, they may be used as raw material in biorefineries, or for the industrial manufacture of many diverse products, given their lignocellulosic composition. Like other lignocellulosic biomasses, the composition of olive leaves depends on cultivar and to know it is essential for an adequate use. Therefore, this work tackles a characterization analysis of the lignocellulosic fraction of some olive leaf cultivars, both commercial and wild. In general, the cultivars studied did not show large differences in their quantitative composition, except for the content of ethanolic extractives and cellulose of the commercial and wild cultivars. In addition, the high lignin content (around 15%) is remarkable.


Assuntos
Lignina/química , Olea/química , Açúcares/química , Biomassa , Extratos Vegetais/química , Folhas de Planta/química
6.
Food Chem ; 329: 127191, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32505985

RESUMO

The awareness of the functional and nutraceutical properties of olives and olive oil bioactive constituents contributed to oliviculture recent increase. Olives' metabolism and nutritional quality are determined by how the olive-tree is coping to climate change-related episodes, which increasingly occur in the Mediterranean. We characterize the most relevant lipophilic and phenolic compounds of olives from Olea europaea cultivars [Cobrançosa, Cordovil de Castelo Branco and Cordovil de Serpa (C.Serpa)] exposed to drought + heat. Olives from the three cultivars presented a similar qualitative profile but differed in their relative richness. Cobrançosa olives are richer in organic acids, esters and carbohydrates, while C.Serpa olives have higher levels of phenolic compounds, particularly under control conditions. Drought + heat changed the quantitative profile of olives, in a way dependent on the cultivar, and C.Serpa olives showed the highest stress susceptibility. Climate change-related conditions stimulate the accumulation of relevant bioactive compounds in olives, contributing to increasing its nutritional value.


Assuntos
Secas , Lipídeos/análise , Olea/química , Azeite de Oliva/análise , Fenóis/análise , Mudança Climática , Flavonoides/análise , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Iridoides/análise , Limite de Detecção , Olea/metabolismo , Fenóis/metabolismo , Análise de Componente Principal , Temperatura
7.
PLoS One ; 15(5): e0232997, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442165

RESUMO

In this study, activated carbons prepared from the green and black olive stone (green OSAC and black OSAC) were used as adsorbents to investigate their removal efficiencies for oxidation products and polar compounds from used sunflower and corn cooking oils. The degree of oxidation level and polar compounds were evaluated using Fourier transform infrared (FTIR) with the principal component analysis and ultra-performance liquid chromatography. Two FTIR absorption peaks were used for the oil evaluation, namely 3007-3009 cm-1, which is related to C-H symmetric stretching vibration of the cis double bonds, and ~1743 cm-1, which is related to = CH and ester carbonyl stretching vibration of the functional groups of the triglycerides, C = O. The principal component analysis results showed significant variations in the oxidation level of the sunflower and the corn oils occurred after consecutive heating and French fries frying for 10 days. The oxidation products that are adsorbed on the surface of the OSAC forms π-complexes with the C = C parts of the OSAC system. It can be concluded that the prepared adsorbents can be promising, efficient, economically effective, and environmentally friendly alternative adsorbents for oil treatment applications.


Assuntos
Carvão Vegetal/isolamento & purificação , Olea/química , Óleos Vegetais/química , Adsorção , Culinária , Óleo de Milho/química , Efeito Estufa/prevenção & controle , Temperatura Alta , Microscopia Eletrônica de Varredura , Análise Multivariada , Olea/ultraestrutura , Azeite de Oliva/química , Oxirredução , Análise de Componente Principal , Catar , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Óleo de Girassol/química
8.
Adv Exp Med Biol ; 1194: 243-251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468540

RESUMO

Olive oil is a key ingredient in the Mediterranean diet and offers many health benefits. However, many factors affect the quality and quantity of olive oil such as olive tree diseases and olive-related pests. Unfortunately, the procedure of identifying pests or the outbreak of a disease is time-consuming, and it depends heavily on the size of the olive grove. Through the use of ICT, remote monitoring of the olive grove can be achieved, by collecting environment-related data and having an overview of the olive grove's overall health. In this paper we propose a low-cost dense network of sensors that collects daily data regarding the olive grove, thus, providing the possibility to prevent infestation of olive fruit fly and/or the outbreak of olive tree-related disease.


Assuntos
Azeite de Oliva , Preparações Farmacêuticas , Tecnologia de Sensoriamento Remoto , Dieta Mediterrânea , Frutas/química , Olea/química , Azeite de Oliva/química , Azeite de Oliva/isolamento & purificação , Doenças das Plantas/prevenção & controle , Óleos Vegetais/isolamento & purificação , Tecnologia de Sensoriamento Remoto/tendências
9.
Food Chem ; 320: 126630, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32224421

RESUMO

The development of a new comprehensive two-dimensional liquid chromatographic method is described, to obtain the profiles of polyphenolic compounds present in olive (Olea europaea L.) leaves and pulps from different genetic origin. Optimisation of the stationary phase nature, particle size, column length and internal diameter, as well as other separation conditions, was performed. Along the study, three stationary phases (C18, PFP and phenyl) in the first dimension (1D), and five (C18, amide, cyano, phenyl and PFP) in the second dimension (2D) were combined to obtain the maximal number of resolved peaks. The optimised method successfully characterised the presence of 26and 29 common polyphenols in olive leaves and pulp extracts, respectively. Peak volume ratios were used to develop linear discriminant analysis models able to distinguish olive leaves and pulp extracts among seven cultivars from several Spanish regions. The results demonstrate that polyphenolic profiles were characteristic of each cultivar.


Assuntos
Olea/química , Extratos Vegetais/química , Polifenóis/química , Cromatografia Líquida de Alta Pressão/métodos , Folhas de Planta/química
10.
J Chromatogr A ; 1620: 461008, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32252985

RESUMO

Table olives, a widely consumed delicacy, are often selected by consumers based on the shade of their green color. The appealing coloration of fresh olives fades to brown or pale yellow during the industrial processing necessary for commercialization and storage, as a result of the degradation of chlorophyll a and b to their corresponding pheophytins and other chlorophyll degradation products (CDP). The re-greening of table olives may be achieved by complexation of CDP with Cu2+, to form stable bright green copper CDP (Cu-CDP) complexes. To study this phenomenon, we developed a novel method to separately extract lipophilic and hydrophilic Cu-CDP and quantify Cu-CDP by UHPLC combined with inductively coupled plasma isotope dilution mass spectrometry (UHPLC-ICP-ID-MS) using post-column isotopic dilution with 65Cu. This technique does not require species-specific calibration standards and was applied to survey the Cu-CDP composition of the various types of table olives sold in the US market. The CDP and Cu-CDP extracted from table olives were identified by high resolution full-scan mass spectrometry. Total elemental Cu in table olives was measured by microwave digestion followed by ICP-MS detection and correlated with the content of Cu-CDP. Pale yellow olives contained <1 mg/kg lipophilic Cu-CDP and <3.5 mg/kg total elemental Cu. Bright green table olives contained 4-22 mg/kg lipophilic Cu-CDP and 14.4-161 mg/kg total elemental Cu in contrast to <6 mg/kg reported for natural abundance, indicating the formation of Cu-CDP was achieved by addition of copper salts. A dark green sample with 2.5 mg/kg of total copper and 0.267 mg/kg lipophilic Cu-CDP may have been processed by addition of sodium copper chlorophyllin (SCC); the higher content of Cu isochlorin e4 compared to Cu 152-Me-chlorin e6 supports this conclusion.


Assuntos
Clorofila/análise , Cromatografia Líquida de Alta Pressão/métodos , Cobre/análise , Espectrometria de Massas/métodos , Sulfato de Cobre/química , Interações Hidrofóbicas e Hidrofílicas , Técnicas de Diluição do Indicador , Isótopos , Olea/química , Porfirinas/química , Sódio/análise
11.
J Food Sci ; 85(5): 1500-1512, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32267966

RESUMO

Olive pomace is considered a solid by-product and a rich source of valuable compounds such as polyphenols, flavonoids with antioxidant properties, and proteins. Nonthermal technologies, which cause alterations to cell permeability, are being explored to assist conventional recovery techniques. The aim of this study was to assess the effect of pulsed electric fields (PEF) and high pressure (HP) on improved recovery yield of the high-added-value compounds or to shorten the extraction time of these compounds. Olive pomace (Tsounati cv) was pretreated with PEF (1.0 to 6.5 kV/cm, 0.9 to 51.1 kJ/kg, and 15 µs pulse width) or HP (200 to 600 MPa and 0 to 40 min). Evaluation of the intracellular compounds extracted via solid-liquid extraction (50% ethanol-water solution) was performed. More intense PEF and HP conditions resulted in a significant increase of the phenolic concentration up to 91.6% and 71.8%, respectively. The increased antioxidant capacity of each extract was correlated to phenolic compound concentration. The protein concentration that was achieved with PEF pretreatment was doubled; however, HP-pretreated extracts reached 88.1% higher yield than untreated for pressures up to 200 MPa. HP and PEF pretreatment decreased extraction completion time t98 (needed time to recover the equal amount of phenolics and proteins of untreated after 60 min of conventional extraction) to 12 min and lower than 1 min, respectively. To conclude, both pretreatments are effective in improving the conventional extraction process for increased yield recovery of high-added-value compounds from olive pomace.


Assuntos
Manipulação de Alimentos/métodos , Olea/química , Extratos Vegetais/isolamento & purificação , Resíduos/análise , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Eletricidade , Flavonoides/análise , Flavonoides/isolamento & purificação , Manipulação de Alimentos/instrumentação , Frutas/química , Extratos Vegetais/análise , Polifenóis/análise , Polifenóis/isolamento & purificação
12.
J Agric Food Chem ; 68(14): 4237-4244, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32186189

RESUMO

Previous studies demonstrated that peptides produced by the hydrolysis of olive seed proteins using Alcalase enzyme showed in vitro multifunctional lipid-lowering capability. This work presents a deeper insight into the hypolipidemic effect of olive seed peptides. The capability of olive seed peptides to inhibit endogenous cholesterol biosynthesis through the inhibition of HMG-CoA reductase enzyme was evaluated observing a 38 ± 7% of inhibition. Two in vivo assays using different peptides concentrations (200 and 400 mg/kg/day) were designed to evaluate the hypolipidemic effect of olive seed peptides in male and female mice. A low concentration of hydrolysate reduced total cholesterol in male mice in a 20% after 11 weeks compared to the mice feeding with hypercholesterolemic diet. A higher hydrolysate concentration showed a greater reduction in total cholesterol (25%). The analysis of the olive seed hydrolysate by reverse phase high-performance liquid chromatography mass spectrometry (RP-HPLC-MS) enabled the identification of peptides that could be responsible for this hypolipidemic effect.


Assuntos
Hipolipemiantes/química , Olea/química , Peptídeos/química , Extratos Vegetais/química , Sementes/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/biossíntese , Colesterol/metabolismo , Cromatografia Líquida de Alta Pressão , Dieta , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Hidrólise , Hidroximetilglutaril-CoA Redutases/metabolismo , Hipolipemiantes/farmacologia , Masculino , Camundongos , Peptídeos/farmacologia , Extratos Vegetais/farmacologia , Hidrolisados de Proteína/química , Espectrometria de Massas em Tandem
13.
Food Chem ; 320: 126626, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222659

RESUMO

Olive leaves are considered a promising source of bioactives such as phenolic compounds and mannitol. The extraction of high added value products is an issue of great interest and importance from the point of view of their exploitation. However, the content of these compounds can differ between cultivars and extraction methods. In this work, six olive leaves cultivars, including three wild cultivars, and two extraction processes (an innovative and alternative technique, pressurized liquid extraction, and a conventional Soxhlet extraction) were evaluated and compared towards the selective recovery of bioactive compounds. The wild cultivars showed the highest content of phenolic and flavonoid compounds, being oleuropein the compound present in higher amount. Findings also revealed that the highest mannitol content in the extracts was observed with the commercial cultivars, specifically in Arbequina. It is thus possible to decide which cultivars to use in order to obtain the highest yield of each bioproduct.


Assuntos
Manitol/análise , Olea/química , Fenóis/análise , Extratos Vegetais/química , Flavonoides/análise , Iridoides/análise , Folhas de Planta/química , Pressão , Espanha
14.
J Chromatogr A ; 1621: 461038, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199674

RESUMO

A QuEChERS method was optimized and validated for the LC-MS/MS analysis of perfluoro-n-pentanoic acid (PFPeA), perfluoro-1-butanesulfonic acid (PFBuS), perfluoro-n-hexanoic acid (PFHxA), perfluoro-n-heptanoic acid (PFHpA), perfluoro-1-hexanesulfonic acid (PFHxS), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), perfluoro-1-octanesulfonic acid (PFOS) and perfluoro-n-decanoic acid (PFDA) in freeze-dried strawberry and olive, as model fruits characterized by very different chemical compositions. The method was evaluated for apparent recovery, intra-day and inter-day precision, matrix effect and recovery. The method optimized for strawberry provided for most compounds absolute values of matrix effect (|ME%|) ≤ 11%, except for PFHxA, which showed a signal suppression of 22%. The extraction efficiency was tested at the spike levels 500-5000 pg/g d.w. for PFPeA, PFBuS, and PFHxA, and 100-1000 pg/g d.w. for the other target analytes, evidencing as a whole recoveries in the range of 65-89%. For olive fruits, due to their high fat content, an ultrasound-assisted extraction was necessary to obtain an efficient sample disgregation so as to increase the extraction yield and its precision. Moreover, a d-SPE clean-up with GCB allowed to achieve |ME%| ≤ 8% (except for PFBuS, which showed a signal enhancement of 19%) and recoveries calculated at the aforementioned spike levels were in the range 75-97%. The two methods provided very good linearity (R2 ≥ 0.9984) from 10,000 pg/g down to compound specific quantification limits, which were included in the ranges of 2.9-393 pg/g and 2.6-127 pg/g for strawberry and olive fruit, respectively. The methods were applied to the analysis of PFAAs in strawberry and olive fruits commercially available in two Italian supermarkets, as well as obtained under irrigation with various treated wastewaters (TWWs), evidencing in both cases a higher PFAAs occurrence in olives than in strawberry. However, PFAAs concentrations determined in the investigated fruit matrixes were quite low, being their sum 1.9 ng/g d.w. in the worst case (i.e. olive fruits grown under irrigation with TWWs).


Assuntos
Cromatografia Líquida/métodos , Fluorcarbonetos/análise , Fragaria/química , Frutas/química , Olea/química , Espectrometria de Massas em Tandem/métodos , Irrigação Agrícola , Produtos Agrícolas/química , Águas Residuárias
15.
Biochim Biophys Acta Biomembr ; 1862(6): 183258, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32142819

RESUMO

Ole e 7 allergen from Olea europaea pollen possesses a major clinical relevance because it produces severe symptoms, such as anaphylaxis, in allergic patients exposed to high olive pollen counts. Ole e 7 is a non-specific lipid transfer protein (nsLTP) characterized by the presence of a tunnel-like hydrophobic cavity, which may be suitable for hosting and, thus, transporting lipids -as it has been described for other nsLTPs-. The identification of the primary amino acid sequence of Ole e 7, and its production as a recombinant allergen, allowed characterizing its lipid-binding properties and its effect at air-liquid interfaces. Fluorescence and interferometry experiments were performed using different phospholipid molecular species and free fatty acids to analyse the lipid-binding ability and specificity of the allergen. Molecular modelling of the allergen was used to determine the potential regions involved in lipid interaction. Changes in Ole e 7 structure after lipid interaction were analysed by circular dichroism. Changes in the IgE binding upon ligand interaction were determined by ELISA. Wilhelmy balance measurements and fluorescence surfactant adsorption tests were performed to analyse the surface activity of the allergen. Using these different approaches, we have demonstrated the ability of Ole e 7 to interact and bind to a wide range of lipids, especially negatively charged phospholipids and oleic acid. We have also identified the protein structural regions and the residues potentially involved in that interaction, suggesting how lipid-protein interactions could define the behaviour of the allergen once inhaled at the airways.


Assuntos
Imunoglobulina E/metabolismo , Metabolismo dos Lipídeos/imunologia , Olea/imunologia , Proteínas de Plantas/metabolismo , Modelos Moleculares , Estrutura Molecular , Olea/química , Olea/metabolismo , Ácido Oleico/metabolismo , Fosfolipídeos/metabolismo , Proteínas de Plantas/química , Ligação Proteica
16.
Sci Rep ; 10(1): 1666, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015351

RESUMO

Plant nutritional quality and chemical characteristics may affect the fitness of phytophagous insects. Here, the olfactory preferences of Bactrocera oleae (Rossi) females toward olives with different maturation and infestation status were evaluated in three cultivars: Ottobratica, Roggianella and Sinopolese. Volatile profiles from olives were identified by SPME/GC-MS. Choice tests were performed to determine the responses of B. oleae adult females toward fruits and pure chemicals linked to infestation degree. Cultivar was the main source of variability explaining the differences recorded in volatile emissions. Moreover, three VOCs [ß-myrcene, limonene and (E)-ß-ocimene] were associated to infestation status across all olive varieties. In choice-tests, B. oleae females always preferred the olfactory cues from low-infested over high-infested fruits. Therefore, choice-tests using synthetic VOCs, emitted in greater amount by high-infested fruit, were arranged in order to identify putative B. oleae kairomones. While females were indifferent to ß-myrcene, the highest dosages of limonene and (E)-ß-ocimene were unfavoured by the tested flies, which preferentially moved toward the empty arm of the Y-tube. Furthermore, females preferred the lowest concentration of ß-ocimene compared to the highest one. These results supported our hypothesis that fruit VOCs may serve as kairomones for female flies.


Assuntos
Olea/química , Olea/parasitologia , Tephritidae/fisiologia , Monoterpenos Acíclicos/química , Alcenos/química , Animais , Quimiotaxia/fisiologia , Feminino , Preferências Alimentares/fisiologia , Frutas/química , Frutas/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Especificidade de Hospedeiro , Limoneno/química , Odorantes/análise , Oviposição/fisiologia , Feromônios/química , Feromônios/fisiologia , Olfato/fisiologia , Compostos Orgânicos Voláteis/química
17.
Food Chem ; 316: 126351, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32050114

RESUMO

The debittering of natural table olives is a very slow process. The effect of acetic, lactic and citric acids on the hydrolysis rate of oleuropein was studied in vitro and at pilot plant scale. The acid hydrolysis of oleuropein was faster with lactic and citric acids than acetic acid, running the experiments at the same pH of 3.8-4.0 units. The temperature exerted a high effect of the hydrolysis of oleuropein in a range of 10-30 °C and the concentration of the organic acid did not show a significant trend. Moreover, the in vitro results were confirmed with three lots of olives that presented a higher content of oleuropein after 3-7 months of preservation when they were processed with acetic acid rather than lactic acid and the opposite for hydroxytyrosol. These results open the possibility of accelerating the debittering of natural olives by preserving them with lactic acid instead of acetic acid.


Assuntos
Ácido Acético/química , Iridoides/química , Ácido Láctico/química , Olea/química , Hidrólise
18.
Mikrobiyol Bul ; 54(1): 79-94, 2020 Jan.
Artigo em Turco | MEDLINE | ID: mdl-32050880

RESUMO

While acyclovir, a nucleoside analogue, is widely used for herpes simplex virus type 1 (HSV-1), emergence of drug-resistant viruses due to frequent usage of this class of medicines, and their toxic side effects require exploring novel active molecules. Despite the studies on developing synthetic molecules in medical sciences and pharmacology, herbs as a natural source of biologically-active compounds remain popular. In this in vitro study, olive leaf extract (OLE) and propolis alone or in combination with acyclovir were investigated for their antiviral efficacy in HSV-1.Toxic doses of OLE, propolis, and dimethyl sulfoxide, propolis diluent, for Hep-2 (ATCC, CCL-23) cells were determined by conventional cell culture. Using "endpoint" method, the viral dose infecting half of the cell culture (TCID50) was calculated, and viral quantity was determined with Spearman-Karber method. Antiviral effects of OLE and propolis on HSV-1 were investigated by conventional cell culture and real-time cell analysis (RTCA). Combinations of the two extracts with one another and with acyclovir were evaluated by RTCA. Active substances prepared at three different dilutions were added to tubes with HSV-1 of logTCID50: 11.5 in descending order starting from the highest non-toxic concentration, and they were left at room temperature for two different durations (one hour and three hours). The aliquots taken from the tubes were cultured in plates containing Hep-2 cells and evaluated after 72 hours. Combinations of extracts and acyclovir at concentrations at least four times lower than the lowest concentration showing antiviral efficacy against HSV-1 were cultured with Hep-2 cells in the e-plates of the xCELLigence RTCA device, measurements were obtained at 30 minute intervals, and data were recorded in real time. In the test with two different durations and at different concentrations of OLE and propolis, antiviral efficacy was observed both with one-hour and three-hour incubation at a concentration of 10 µg/ ml for propolis and 1.2 mg/ml for OLE with RTCA. The duration and concentration of the greatest decrease in viral quantity were in the first one hour and 10 µg/ml for propolis, and in the first one hour and 1.2 mg/ ml for OLE. Combination of propolis and OLE with acyclovir caused no cytopathic effects, and the combination of extracts led to delayed cytopathic effect. According to these results, propolis and OLE, alone and in combinations with acyclovir, have antiviral efficacy against HSV-1. These agents may reduce the dose and side effects of acyclovir in case of co-administration since they exert their effects through a different mechanism than acyclovir,possibly through direct virucidal activity, inhibition of virus internalization or viral inhibition in early stages of replication (inhibition of adsorption/binding of viral particles to the cell). These extracts that do not require conversion to active form have the potential to reduce infectivity in oral lesions, prevent spread, and be used in the topical treatment of acyclovir-resistant HSV infections, particularly in immunocompromised patients. However, in vivo studies should be conducted to determine their medicinal properties and potential toxicities. These results should be supported by further comprehensive studies and the efficacy against other viruses should also be investigated.


Assuntos
Aciclovir , Antivirais , Herpesvirus Humano 1 , Olea , Extratos Vegetais , Própole , Aciclovir/farmacologia , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Humanos , Olea/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Própole/farmacologia
19.
J Agric Food Chem ; 68(10): 3171-3183, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32052628

RESUMO

Reversed-phase liquid chromatography with electrospray ionization-high-resolution/accuracy Fourier transform mass spectrometry (RPC-ESI-FTMS) and chemometrics were exploited to evaluate the influence of horizontal centrifugation by two- or three-phase decanters on the content of major phenolic secoiridoids in extravirgin olive oils (EVOOs). Despite the occurrence of other potential sources of variability typical of commercial olive oils, horizontal centrifugation was found to play a primary role, with a general increase of secoiridoid content occurring when two-phase decanters were used. As emphasized by principal component analysis (PCA), the increase involved preferentially oleacin and oleocanthal, when oxidative deterioration was purposely minimized during and/or after production, and oleuropein and ligstroside aglycones, when no vertical centrifugation was performed at the end of the productive cycle. The influence of the type of horizontal centrifugation was also emphasized by the elaboration of RPC-ESI-FTMS data based on hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA).


Assuntos
Centrifugação/métodos , Manipulação de Alimentos/métodos , Iridoides/química , Azeite de Oliva/química , Fenóis/química , Cromatografia de Fase Reversa , Frutas/química , Olea/química , Oxirredução , Espectrometria de Massas por Ionização por Electrospray
20.
Bioelectrochemistry ; 132: 107404, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31911357

RESUMO

Malathion (MAL) is an organophosphorus (OP) insecticide. It is a cholinesterase inhibitor, which can pose serious health and environmental problems. In this study, a sensitive and selective molecular imprinted polymer (MIP) based on screen-printed gold electrodes (Au-SPE) for MAL detection in olive oils and fruits, was devised. The MIP sensor was prepared using acrylamide as the functional monomer and MAL as the template. Subsequently, the morphology of the electrode surface was studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The electrochemical characterization of the developed MIP sensor was performed by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) techniques. The operational repeatability and stability of the sensor were studied. It was found to have a dynamic concentration range of (0.1 pg mL-1-1000 pg mL-1) and a low limit of detection (LOD) of 0.06 pg mL-1. Furthermore, the sensor was employed to determine MAL content in olive oil with a recovery rate of 87.9% and a relative standard deviation of 8%. It was successfully applied for MAL determination in real samples and promise to open new opportunities for the detection of OP pesticides residues in various food products, as well as in environmental applications.


Assuntos
Técnicas Eletroquímicas/instrumentação , Contaminação de Alimentos/análise , Inseticidas/análise , Malation/análise , Impressão Molecular , Olea/química , Azeite de Oliva/química , Polímeros/química , Limite de Detecção , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes
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