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A promising drying technology, namely combined freeze-drying and far-infrared drying (FD-FIRD) was employed to dehydrate seed-used pumpkin (SUP) and its effects on physical characteristics (color, microstructure, texture, shrinkage), bioactive components (phenolics and carotenoids) of SUP were evaluated. The low-field nuclear magnetic resonance (LF-NMR) was used to analyze moisture state and distribution during FD process, which is beneficial for choosing appropriate moisture transfer point. Results showed that most free water (87.29 %) was removed when drying time reached 25 h, thus retaining original tissue structure of sample with almost no deformation during later FIRD process. Therefore, FD for 25 h followed by FIRD for 2 h (FD25-FIRD2) sample exhibited similar appearance with FD sample. The free phenolics content of FD-FIRD samples was 14.97 %-26.60 % higher than that of FD depending on FIRD duration. Especially, p-coumaric acid content of FD25-FIRD2 sample increased of 32.23 %. Besides, FD-FIRD performed higher retention for carotenoids showing 3.00-3.39 folds than FIRD.
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Cucurbita , Antioxidantes/química , Carotenoides/análisis , Fenoles/análisis , Semillas/química , TecnologíaRESUMEN
An environmentally friendly physical processing method, hydrothermal treatment (HT), was used to increase the content of specific compounds and antioxidant activities of seed-used pumpkin byproducts. The influence of hydrothermal temperature (80 °C-160 °C) and time (30-150 min) on changes in polyphenols and antioxidation was evaluated. The results revealed that the maximum free polyphenol content (140 °C for 120 min) was 3.96-fold higher than the untreated samples. Elevated temperature and long duration changed phenolic acid contents. For example, p-coumaric acid, rutin and chlorogenic acid exhibited a decreasing trend, and p-hydroxybenzoic acid, quercetin and cinnamic acid showed an increasing trend. Compared to controls, HT was significantly associated with increased antioxidant activities. To comprehensively reveal the influence of hydrothermal temperature and time on changes in polyphenolic content, back propagation artificial neural network (BP-ANN) models with accurate prediction ability were developed, and the results exhibited well-fitted and strong approximation ability (R2 > 0.95 and RMSE < 2 %) and stability.
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Antioxidantes , Cucurbita , Fenoles/análisis , Extractos Vegetales , Polifenoles/análisis , Semillas/químicaRESUMEN
Subcritical water extraction (SWE) of four flavoring compounds from cinnamon was performed at various temperatures and for various extraction times. The extraction temperature (°C) and time (min) corresponding to the maximum content of flavoring compounds were 190 °C and 5 min for cinnamyl alcohol, 200 °C and 20 min for cinnamic acid, 130 °C and 10 min for cinnamaldehyde, and 170 °C and 20 min for coumarin, respectively. Cinnamaldehyde underwent structural conversion to benzaldehyde via hydrolysis at high temperatures, and the rate of conversion rapidly increased above 150 °C. The extraction efficiency using subcritical water was slightly higher or comparable to that using conventional extractants. SWE is a potential and highly selectivity technology for extracting flavoring compounds from cinnamon.
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Cinnamomum zeylanicum , Aceites Volátiles , Cinnamomum zeylanicum/química , Aromatizantes , Hidrólisis , AguaRESUMEN
Cinnamomum verum is the widely used spice for its medicinal and culinary uses since ages. It is native to Sri Lanka and southern India but also distributed in many Asian, Caribbean, Australian and African countries. It is widely used in food preparations and industrial products like candies, chewing gums, mouthwash and toothpaste. It is also used to treat asthma, bronchitis, diarrhea, headache, inflammation and cardiac disorders. Cinnamaldehyde, eugenol, caryophyllene, cinnamyl acetate and cinnamic acid are the major compounds found in its essential oil. These compounds exhibit a wide range of pharmacological activities including antioxidant, antimicrobial, anti-inflammatory, anticancer, antidiabetic, wound healing, anti-HIV, anti-anxiety and antidepressant, etc. This review highlights its comprehensive and up-to-date information on taxonomy, ethnomedicinal uses, phytochemical composition, pharmacological and toxicity activities. Structure-activity relationship, mechanism of action and some research gaps has also been provided. Owing to its immense medicinal importance, more well-designed in-vivo and clinical studies are required.
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Cinnamomum zeylanicum/química , Valor Nutritivo , Fitoquímicos/análisis , Especias/análisis , Animales , Etnofarmacología , HumanosRESUMEN
Multi-response optimization of hot pressurized liquid extraction (HPLE) was applied for the first time to obtain maqui (Aristotelia chilensis [Mol.] Stuntz) leaf extracts. The total polyphenol content (TPC), the antioxidant capacity (AC) as well as the total polyphenol purity of the maqui leaf extracts were accurately predicted (RSD < 8%) at the evaluated extraction scales. The optimum HPLE conditions that prioritized TPC and AC equally (OPT1) recovered ~3 times more TPC (205.14 mg GAE/g leaves) than maqui leaf extracts obtained by maceration, while the extract that prioritized purity over TPC and AC presented the highest purity (36.29%) and an EC50 ~3 times lower than currently reported values. It was found by multi-response optimization that maqui leaves and HPLE are among the best natural sources and extraction techniques, respectively, to recover protocatechuic acid, quercetin, and catechin.
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This study aims at determining the potentials of cinnamon (Cinnamomun burmannii) extracts to improve the health-promoting properties of white chocolate. LC-HRMS analysis was employed to obtain information regarding the phytochemical content while the phosphomolybdenum, FRAP and DPPH assays were used to determine antioxidant activity of cinnamon extract. Furthermore, the cinnamon extract was loaded into nanoparticles before adding it to white chocolate. The results show that cinnamon extracts contained phenols up to 310 mg EE and possessed antioxidant activity up to 260 mg TAE per gram of dry extract depending on the extraction mode (i.e., traditional and ultrasonic-assisted method) and the solvent type. The cinnamon extract contained catechin, epicatechin, procyanidin B2, quercitrin, 3,4-dihydroxybenzaldehyde, protocatechuic acid and cinnamic acid at levels of 51, 53, 1396, 13, 1138, 228 and 934 µg/g of dry extract, respectively. The encapsulated cinnamon extract increased the phenolic content of white chocolate from 47.6 to 1060.6 µg EE/g.
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Antioxidantes/química , Chocolate , Cinnamomum zeylanicum/química , Fitoquímicos/análisis , Extractos Vegetales/química , Biflavonoides/análisis , Catequina/análisis , Chocolate/análisis , Microscopía por Crioelectrón , Industria de Procesamiento de Alimentos , Hidroxibenzoatos/análisis , Fenoles/análisis , Extractos Vegetales/análisis , Proantocianidinas/análisis , Quercetina/análogos & derivados , Quercetina/análisis , UltrasonidoRESUMEN
This study examined the effects of exogenous citrulline (control, 1 and 2 mM) and water availability (100%, 50% and 25% WA) on antioxidant attributes and essential oil constituents of Hyssopus officinalis L. in two successive harvests. Hyssop tolerantly responded to water deficiency by well-promoted antioxidant enzymes (i.e., superoxide dismutase, and catalase), strong DPPH-scavenging activity, and increasing polyphenols; however, the essential oil content was negatively reduced by water stress. External citrulline further increased the activity of antioxidant enzymes. Citrulline application at 2 mM under severe water stress could also improve essential oil (EO) content in the first and second harvests by about 15 and 30%, respectively. Furthermore, under severe drought, citrulline at 2 mM could obtain the highest yield of isopinocamphone (47%) as the main component of EO. The results showed the high potential of this novel applied metabolite agent to be used in a well-fulfilled production of this medicinal plant.
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Antioxidantes/metabolismo , Citrulina/farmacología , Hyssopus/efectos de los fármacos , Hyssopus/fisiología , Aceites Volátiles/metabolismo , Canfanos/metabolismo , Catalasa/metabolismo , Catecol Oxidasa/metabolismo , Deshidratación , Sequías , Hyssopus/química , Aceites Volátiles/análisis , Proteínas de Plantas/metabolismo , Plantas Medicinales/efectos de los fármacos , Plantas Medicinales/fisiología , Polifenoles/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
A research was performed to determine and compare the physicochemical properties, chemical compositions and in vitro antioxidant activities of Paeonia lactiflora Pall seed oils with ultrasonic-assisted solvent extraction, pressing and supercritical fluid extraction. Paeonia lactiflora Pall seed oil contained a high percentage of polyunsaturated fatty acids and monounsaturated fatty acids, especially oleic (31.62-32.88%) and α-linolenic acids (37.55-39.95%). The beneficial multiple dietary phytochemicals (tocopherol, phytosterols and squalene) and in vitro antioxidant activity were significantly influenced by the hull and processing method (Pï¼0.05). However, higher tocopherol (596.67-738.76 mg/kg) and phytosterols (5775.01-6055.62 mg/kg) contents were found in supercritical fluid extraction oils. Additionally, ten individual polyphenols were quantified, and significantly influenced by the hull and processing method (Pï¼0.05), with the content of benzoic acid and several individual flavonoids being the higher. According to the results, pressing might be the best process for extracting oil with a high number of polyphenols.
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Paeonia/metabolismo , Aceites de Plantas/química , Cromatografía con Fluido Supercrítico , Depuradores de Radicales Libres/química , Fitosteroles/química , Fitosteroles/aislamiento & purificación , Extractos Vegetales/química , Aceites de Plantas/aislamiento & purificación , Semillas/química , Semillas/metabolismo , Sonicación , Tocoferoles/química , Tocoferoles/aislamiento & purificaciónRESUMEN
The adulteration of honey is generally a safety and quality concern for consumers and the industry as a whole. Resin technologies allow harmful substances to enter honey, creating substandard honey, which can enter the market. Thus, it is necessary to identify such illegal products quickly and easily. In this study, HPLC-ECD combined with chemometrics was used to identify raw acacia honey that had been treated with macroporous adsorption resins. The chromatography fingerprints of 46 honey samples were established, and principal component analysis (PCA) and the OPLS-DA identified that differences in some of the chromatographic peaks could be used to distinguish raw from resins-treated raw honeys. 100% correct classification was achieved with test samples, based on the chromatographic peaks identified. These results show that HPLC-ECD, combined with chemometric methods, can identify correctly resins-treated honey and can be applied for the quality control of honey.
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Acacia/química , Cromatografía Líquida de Alta Presión/métodos , Miel/análisis , Resinas de Plantas/química , Acacia/metabolismo , Adsorción , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Porosidad , Análisis de Componente PrincipalRESUMEN
The Myrtaceae is one of the most common plant families in Brazil, including >1000 species of native fruit spread from North to South, where around 50% of all species are endemic to the Atlantic Rain Forest Biome. Most Brazilian species belong to Eugenia, Campomanesia, Psidium and Myrciaria genera. In general, they are characterized by the presence of leaves opposite, simple, entire, with pellucid glands containing ethereal oils and produces berry-like, fleshy fruits with a wide diversity of beneficial characteristics. Several parts of these plants are widely used in regional folk medicine as an astringent, anti-inflammatory, antihypertensive, to treat gastrointestinal disorders, and so on. Some species have already been studied and most of their metabolic effects are attributed to the presence of polyphenols, carotenoids as well as sesquiterpenes and monoterpenes. In addition, the Myrtaceae family has great economic potential, because of the sensory characteristics which encourages their commercial exploitation plus the presence of phytochemicals which play an important role in managing several degenerative chronic diseases besides representing a hotspot of technological innovation for food, cosmetic and pharmaceutical purposes. In this context, this review discusses about the importance of some Eugenia genera representatives such as Eugenia uniflora, Eugenia stipitata, Eugenia brasiliensis, Eugenia pyriformis and Eugenia dysenterica, emphasizing its profile of bioactive compounds as well as the knowledge of the nutritional and functional fruit potential, providing information for further studies aiming to stimulate the cultivation of Brazilian wild berries, for consumption and new food ingredients.
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Eugenia , Frutas/química , Fitoquímicos , Extractos Vegetales , Animales , Brasil , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Ratones , Fitoquímicos/análisis , Fitoquímicos/química , Fitoquímicos/farmacología , Extractos Vegetales/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacologíaRESUMEN
In this study, a one-step method for producing phytosteryl phenolates, namely phytosteryl cinnamate and ferulate, has been successfully developed and their chemical structures were confirmed by FT-IR, MS and NMR. The highest yield of phytosteryl ferulate (85.7%) was obtained at 100⯰C for 2â¯h after optimization. A Lewis acid catalyst scandium triflate was selected as the catalyst, and it turned out that it could be reused for at least five times without significant loss of activity. Meanwhile, it has been demonstrated that the solubility of phytosteryl phenolates in soybean oil was much higher than in both phenolic acid and phytosterol, which was conducive to expand their applications in oil-based food. The research finding helps realize convenient, green and efficient synthesis of phytosteryl phenolates.
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Hidroxibenzoatos/análisis , Fitosteroles/química , Catálisis , Cromatografía Líquida de Alta Presión , Cobre/química , Ácidos Cumáricos/química , Hidroxibenzoatos/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray , Espectroscopía Infrarroja por Transformada de Fourier , TemperaturaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: A recent ethnomedical survey on medicinal plants grown in Mexico revealed that Sechium edule (Jacq.) Sw. (Cucurbitaceae) is one of the most valued plant species to treat cardiovascular diseases, including hypertension. Fruits, young leaves, buds, stems, and tuberous roots of the plant are edible. Considering that endothelial dysfunction induced by Angiotensin II plays an important role in the pathogenesis of hypertension and is accompanied by a prooxidative condition, which in turn induces an inflammatory state, vascular remodeling, and tissue damage, and that S. edule has been reported to possess antioxidant, anti-inflammatory and antihypertensive activity, its capability to control endothelial dysfunction was also assessed. AIM OF THE STUDY: To assess in vivo the anti-endothelial dysfunction activity of the acetone fraction (rSe-ACE) of the hydroalcoholic extract from S. edule roots. MATERIALS AND METHODS: Endothelial dysfunction was induced in female C57BL/6â¯J mice by a daily intraperitoneal injection of angiotensin II for 10 weeks. Either rSe-ACE or losartan (as a control) were co-administered with angiotensin II for the same period. Blood pressure was measured at weeks 0, 5, and 10. Kidney extracts were prepared to determine IL1ß, IL4, IL6, IL10, IL17, IFNγ, TNFα, and TGFß levels by ELISA, along with the prooxidative status as assessed by the activity of antioxidant enzymes. The expression of ICAM-1 was evaluated by immunohistochemistry in kidney histological sections. Kidney and hepatic damage, as well as vascular tissue remodeling, were studied. RESULTS: The rSe-ACE fraction administered at a dose of 10â¯mg/kg was able to control hypertension, as well as the prooxidative and proinflammatory status in kidney as efficiently as losartan, returning mice to normotensive levels. Additionally, the fraction was more efficient than losartan to prevent liver and kidney damage. Phytochemical characterization identified cinnamic acid as a major compound, and linoleic, palmitic, and myristic acids as the most abundant non-polar components in the mixture, previously reported to aid in the control of hypertension, inflammation, and oxidative stress, three important components of endothelial dysfunction. IN CONCLUSION: this study demonstrated that rSe-ACE has anti-endothelial dysfunction activity in an experimental model and highlights the role of cinnamic acid and fatty acids in the observed effects.
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Cucurbitaceae/química , Endotelio Vascular/efectos de los fármacos , Extractos Vegetales/farmacología , Enfermedades Vasculares/prevención & control , Acetona/química , Angiotensina II/administración & dosificación , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Antioxidantes/metabolismo , Cinamatos/aislamiento & purificación , Cinamatos/farmacología , Modelos Animales de Enfermedad , Endotelio Vascular/patología , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos/farmacología , Femenino , Losartán/farmacología , México , Ratones , Ratones Endogámicos C57BL , Raíces de Plantas , Enfermedades Vasculares/patologíaRESUMEN
Considering the adverse effect of food additives on humans, thorough research of their physiological effects at the molecular level is important. The interactions of cinnamaldehyde (CNMA), a food perfume, and its major metabolite cinnamic acid (CA) with human serum albumin (HSA) were examined by multiple-spectroscopies. NMR analysis revealed CNMA and CA both bound to HSA, and STD-NMR experiments established CNMA and CA primarily interacted with site I and site II of HSA, respectively. The ligands caused strong quenching of HSA fluorescence through a static quenching mechanism, with hydrophobic and electrostatic interaction between CNMA/CA and HSA, respectively. UV-vis absorption and CD results showed ligands induced secondary structure changes of HSA. Binding configurations were proved by docking method. Furthermore, binding constants of CNMA/CA-HSA systems were influenced by the addition of four other food additives. These studies have increased our knowledge regarding the safety and biological action of CNMA and CA.
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Acroleína/análogos & derivados , Cinamatos/metabolismo , Aditivos Alimentarios/metabolismo , Albúmina Sérica Humana/metabolismo , Acroleína/química , Acroleína/metabolismo , Sitios de Unión , Cinamatos/química , Fluorescencia , Aditivos Alimentarios/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Simulación del Acoplamiento Molecular , Unión Proteica , Estructura Secundaria de Proteína , Albúmina Sérica Humana/química , Espectrometría de Fluorescencia , Análisis Espectral , Electricidad Estática , TermodinámicaRESUMEN
The phenolics profile of two new kiwifruit cultivars, Zespri® SunGold and Zespri® Sweet Green, were characterized and quantified for the first time using cyclic voltammetry, an electrochemical method, combined with HPLC. Results from the cyclic voltammetry revealed high correlations with those obtained from the spectrophotometry and HPLC methods, providing evidence to support the application of cyclic voltammetry as a rapid method in determining the phenolic profile and reducing power of kiwifruit extracts. Catechol-containing phenolics were identified as the major phenolic sub-class in the skins while flavonoids and phenolic acids were abundant in flesh of the tested cultivars. Epicatechin was the predominant phenolic compound and contributor to antioxidant capacity in all samples. Results also showed that SunGold and Sweet Green (both flesh and skin) exhibited significantly higher phenolic contents and antioxidant activities comparing with the well-established commercial 'Hayward' cultivar, indicating their commercial value and potential applications in food and nutraceuticals.
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Actinidia/química , Antioxidantes/análisis , Frutas/química , Fenoles/análisis , Actinidia/crecimiento & desarrollo , Antioxidantes/química , Cromatografía Líquida de Alta Presión , Electroquímica , Fenoles/químicaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Nowadays, bronchial asthma is still a severe disease threatening human health, and it is incumbent upon us to seek effective therapeutic drugs. Mahuang decoction (MHD), a classic famous Chinese prescription, has been used for thousands of years to prevent phlegm from forming, stop coughing and relieve asthma, but the relevant mechanism has not been thoroughly clarified. This study aims to investigate the anti-airway inflammation effect of MHD and the possible molecular mechanism underlying IL21/STAT3 signaling pathway, so as to provide guidance for the treatment of MHD on bronchial asthma. MATERIALS AND METHODS: Specific pathogen free SD rats were randomly divided into 6 groups: normal control group, model group, positive group (Compound methoxyphenamine), MHD-treated groups at doses of 10â¯ml/kg, 5â¯ml/kg and 2.5â¯ml/kg, 10 rats in each group. Except for the normal control group, rats in other groups were sensitized with ovalbumin via introperitoneal injection and challenged with ovalbumin inhalation to trigger asthma model. At 24â¯h after the last excitation, bronchoalveolar lavage fluid (BALF) of every rat was drawn and the number of inflammatory cells was analyzed using cell counting method. ELISA method was performed to determine the concentrations of TXB2, 6-keto-PGF1α, MMP-9, TIMP-1, IL-2, IL-4, IL-5 and TNF-α in rat serum. The protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in murine pulmonary tissues were assessed with western blotting analysis. RESULTS: Compared with the control group, the airway wall and airway smooth muscle of murine pulmonary tissues significantly thickened and massive inflammatory cells infiltration occurred around the bronchus in the model group, and the cell counts of WBC and EOS in BALF were also apparently increased, which indicated the rat asthma model was successfully established. MHD or Compound methoxyphenamine not only alleviated the pulmonary inflammatory pathological damages, but also down- regulated the numbers of WBC and EOS in BALF. What's more, the levels of TXB2, MMP-9, TIMP-1, ILs-(2, 4, 5) and TNF-α in rat serum were lessened by the treatment of MHD. In western blotting analysis, treatment with 10â¯ml/kg or 5â¯ml/kg MHD markedly declined the increased protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in lung tissues of asthmatic rats to normal level. CONCLUSION: MHD intervention demonstrated a strong inhibitory action on the secretion of inflammatory mediators as well as the inflammatory cell infiltration in pulmonary tissues of asthmatic rats, and also depressed the protein expressions of IL-21, IL-21R, STAT3 and p-STAT3 in pulmonary tissues. MHD effectively mitigates airway inflammation and regulates the IL-21/STAT3 signaling pathway in rat asthma model.
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Antiasmáticos , Asma/tratamiento farmacológico , Citocinas/inmunología , Preparaciones de Plantas , Factor de Transcripción STAT3/inmunología , 6-Cetoprostaglandina F1 alfa/sangre , Alérgenos , Animales , Antiasmáticos/farmacología , Antiasmáticos/uso terapéutico , Asma/sangre , Asma/inmunología , Asma/patología , Líquido del Lavado Bronquioalveolar/citología , Citocinas/sangre , Modelos Animales de Enfermedad , Ephedra sinica , Recuento de Leucocitos , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Metaloproteinasa 9 de la Matriz/sangre , Ovalbúmina , Fitoterapia , Preparaciones de Plantas/farmacología , Preparaciones de Plantas/uso terapéutico , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Tromboxano B2/sangre , Inhibidor Tisular de Metaloproteinasa-1/sangreRESUMEN
To study the diversity and cultivar-specific of phytochemicals in sweet potato, Liquid Chromatography-Electrospray Ionization-Mass Spectrometry was used to analyze the metabolic profiles of five sweet potato cultivars exhibiting different flesh colors: purple, yellow/orange, and white. A total of 213 metabolites, including 29 flavonoids and 27 phenolic acids, were characterized. The flavonoid profiles of the five different cultivars were distinguished using PCA, the results suggested the flesh color accounted for the observed metabolic differences. In addition to anthocyanins, quinic acids and ferulic acids were the prominent phenolic acids, O-hexoside of quercetin, chrysoeriol were the prominent flavonoids in sweet potato tubers, and they were all higher in the OFSP and PFSP than WFSP. The main differential metabolic pathways between the OFSP, PFSP and the WFSP included those relating to phenylpropanoid and flavonoid biosynthesis. This study provides new insights into the differences in metabolite profiles among sweet potatoes with different flesh colors.
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Flavonoides/análisis , Ipomoea batatas/metabolismo , Pigmentación/fisiología , Tubérculos de la Planta/metabolismo , Antocianinas/análisis , Cromatografía Liquida , Ácidos Cumáricos/análisis , Flavonas/análisis , Hidroxibenzoatos/análisis , Ipomoea batatas/química , Metabolómica/métodos , Análisis Multivariante , Tubérculos de la Planta/química , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
Cinnamic acid (CA) and methyl cinnamate (MC) have attracted interest of researchers because of their broad therapeutic functions. Here, we investigated the interaction of CA and MC with bovine serum albumin (BSA) at pH 3.5, 5.0, and 7.4 using fluorescence spectroscopy, differential scanning nanocalorimetry, and measurements of interfacial tension, size, and zeta potential. BSA formed a complex with the ligands with stoichiometry of approximately 1.0. At pH 7.4, CA-BSA complex formation was entropically driven. The interaction between MC and BSA was more favorable than with CA and was enthalpically driven under the same conditions. The pH played an important role in BSA conformation, which altered the manner in which it interacts with the ligands. Interestingly, both CA and MC had no effect on the surface tension of BSA/air interfaces. These data contribute to the knowledge of CA/MC-BSA interactions and provide important data for application in the food industry.
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Cinamatos/análisis , Albúmina Sérica Bovina/análisis , Unión Proteica , Espectrometría de Fluorescencia , TermodinámicaRESUMEN
Phenylalanine ammonia lyase (PAL) from Arabidopsis thaliana (AtPAL2) is in general a very good catalyst for the amination of fluoro- and chloro-cinnamic acid derivatives yielding halogenated (S)-phenylalanine derivatives with ≥85% conversion and excellent ee values >99%. We have studied the application of this enzyme as whole cell biocatalyst and immobilized on the cellulose carrier Avicel® for the production of the hypertension drug precursor (S)-2-chloro-phenylalanine using batch, fed-batch, as well as continuous membrane reactor and plug-flow reactor. For immobilization, a C-terminal fusion of the enzyme with a carbohydrate binding module (CBM) was produced, which selectively binds to Avicel® directly from crude cell extracts, thus enabling a fast and cheap immobilization, stabilization and recycling of the enzyme. 1g Avicel was loaded with 10mg enzyme. Best results were obtained with whole cells using the continuous membrane reactor (47gproduct/gDryCellWeight) and using the immobilized enzyme in a repetitive fed-batch (274gproduct/gimmobilized enzyme) or in a continuous plug-flow reactor (288gproduct/gimmobilize enzyme). Therewith the productivity of AtPAL2 outperforms the established fed-batch process at DSM using PAL from Rhodotorula glutinis in E. coli as whole cell biocatalyst with a productivity of 0.14gproduct/gWetCellWeight (ca. 0.7gproduct/gDryCellWeight) (de Lange et al., 2011; doi:10.1002/cctc.201000435).
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Arabidopsis/enzimología , Imidazoles/química , Fenilanina Amoníaco-Liasa/metabolismo , Fenilalanina/metabolismo , Proteínas de Plantas/metabolismo , Reactores Biológicos , Ingeniería Metabólica , Fenilalanina/análogos & derivados , Fenilalanina/química , Fenilanina Amoníaco-Liasa/análisis , Fenilanina Amoníaco-Liasa/química , Fenilanina Amoníaco-Liasa/genética , Proteínas de Plantas/análisis , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas Recombinantes/análisis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , EstereoisomerismoRESUMEN
Light and temperature are two of the most important factors regulating postharvest strawberry aroma. To date the majority of research has been concentrated on the contribution of either light or temperature factors in isolation. In the present study, we investigated integrated effects of light and temperature on the formation of characteristic aromas during postharvest strawberry ripening process. Most volatiles including volatile esters, volatile furanones, and volatile terpenes showed increasing trends, whereas volatile benzenoids showed decreasing trends during postharvest ripening. Biosyntheses of volatile esters and volatile benzenoids were mainly affected by interaction of temperature and dark, whereas formation of volatile furanones and volatile terpenes were mostly influenced by temperature and dark, respectively. This study provided evidence of regulation of strawberry aroma by dual factors for the first time, and characterized a comprehensive profile of formations of strawberry aromas in response to light and temperature during postharvest ripening.
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Vías Biosintéticas/fisiología , Fragaria/metabolismo , Luz , Odorantes/análisis , Temperatura , Ésteres/metabolismo , Aromatizantes/metabolismo , Terpenos/metabolismoRESUMEN
Cinnamon and cocoa are known to be valuable sources of bioactive phytochemicals, mainly the polyphenols. This paper investigates the potential antioxidant activity of cinnamon and cocoa extract and the interaction of their mixtures by various in vitro tests. Moreover, the combination effect of their constituents in a binary mixture was studied. Two representative active compounds of chocolate (epicatechin, catechin) were combined with seven of cinnamon (gallic acid, tannic acid, quercetin, sinapic acid, cinnamic acid, eugenol and cinnamaldehyde) in multilevel ratios. The results indicate that the addition of the cinnamon extract significantly increased the antioxidant activity of the cocoa extract. The interaction ranged from synergetic to antagonistic. The interaction was less synergetic when cinnamon extract was added in higher proportion. The interaction of their constituents substantially influenced the antioxidant activity of the mixture and was dependent on the ratio. The kinetics' study could elucidate how the polyphenols work in a mixture.