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1.
J Agric Food Chem ; 68(8): 2578-2587, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31961151

RESUMO

Chlorpropham is a widely used sprouting inhibitor applied on potatoes during their storage. Currently, severe concerns are raised regarding the potential formation of 3-chloroaniline from chlorpropham during heat treatment. The reactions degrading the molecule in the matrix are quite complex under harsh processing conditions, and a molecular investigation is thus challenging. This study aims to decipher the reaction pathways and to discover new metabolites in typical high-temperature food-processing steps. For this purpose, potatoes were treated with 14C-radiolabeled chlorpropham, stored for up to 6 months, and subjected to the traditional preparation steps of boiling, frying, and baking. A quantification method including an acidic hydrolysis was developed for analysis of free and bound analytes. All conducted processing steps led to a substantial mitigation of chlorpropham residues in the consumable products. Of the residues, 17 ± 6% remained in boiled tubers, while 27 ± 3 and 22 ± 3% remained in the fried and baked products, respectively. Chlorpropham was transferred into the surrounding media (boiling water, frying oil, and air, respectively). 3-Chloroaniline was only (raw tubers) or predominantly (processed tubers) present as a bound analyte and was shown to form during storage but not during processing. Additionally, nonextractable and nonquantified residues were detected in the baked and in the long-term-stored tubers after processing. Future studies will have to balance beneficial (mitigating) and potentially hazardous aspects of these results. By transferring the 14C-food-processing approach to a variety of substances, ingredients, and processes, it will be possible to further understand chemical reactions in food processing, finally leading to safer food.


Assuntos
Clorprofam/química , Herbicidas/química , Solanum tuberosum/química , Culinária , Temperatura Alta , Resíduos de Praguicidas/química , Tubérculos/química
2.
J Agric Food Chem ; 68(6): 1596-1608, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31927925

RESUMO

Purple sweet potato is known as a rich source of protein and anthocyanins. Anthocyanins can form complexes with protein present in food products through non-covalent forces or covalent bonds during processing, transportation, and storage as their protein affinity. We evaluated the hypoglycemic effects of protein-bound anthocyanin compounds of purple sweet potato (p-BAC-PSP) and free anthocyanin compounds of purple sweet potato (FAC-PSP) in high-fat diet/streptozotocin-induced diabetic mice. The results showed that administration of both p-BAC-PSP and FAC-PSP improved diabetic condition, as evidenced by the improvement of glucose tolerance and lipid metabolism, and the decrease of oxidative stress and liver damage. For the mechanism study, we have found that p-BAC-PSP and FAC-PSP induced the expression of AMP-activated protein kinase in liver. With p-BAC-PSP or FAC-PSP treatment, glucose transporter type 2, the protein levels of glucokinase, and insulin receptor α were found to be improved significantly (p < 0.05). Glycolysis key genes, phosphofructokinase and pyruvate kinase, were upregulated in two treatment groups, while gluconeogenic genes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, were downregulated. Our findings suggested that p-BAC-PSP has great potential as a dietary supplement with hypoglycemic activity for general, pre-diabetic, and diabetic population.


Assuntos
Antocianinas/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Ipomoea batatas/química , Fígado/metabolismo , Extratos Vegetais/administração & dosagem , Proteínas de Plantas/administração & dosagem , Animais , Antocianinas/química , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Humanos , Hiperglicemia/metabolismo , Hipoglicemiantes/química , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/química , Proteínas de Plantas/química , Tubérculos/química
3.
J Sci Food Agric ; 100(4): 1702-1710, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31803935

RESUMO

BACKGROUND: The presence of insoluble calcium oxalate druse crystals (CaOx) in sweet potato (Ipomoea batatas) can negatively affect its nutritional quality. Photosynthesis, starch, and protein composition are linked with oxalate synthesis and tuber quality under water scarcity. Our main objective was the oxalate quantitation of sweet potato tubers and shoots and also to assess how drought changes their nutritional value. Eight sweet potato accessions from Madeira, the Canaries and Guinea-Bissau were analyzed for their response to drought stress. Tubers and shoots were analyzed for total (T-Ox), soluble (S-Ox) and insoluble (CaOx) oxalates, protein, chlorophyll content index (CCI), soluble starch, starch swelling power, and starch solubility in water. RESULTS: The S-Ox and CaOx content was higher in shoots. Six accessions were above maximum CaOx levels for raw consumption. Accessions with more favorable responses to drought had decreased CaOx with S-Ox increase content for osmoregulation. They also presented slightly decreased CCI and protein contents. These accessions also had an increased shoot starch content, for further tuber storage starch hydrolysis, and maintained the quality and functional properties of the tuber starch grain. Those with a less favorable response to drought had a higher T-Ox and CaOx content in both organs, hindering water absorption. They also had decreased protein and CCI, with a slight increase in tuber starch hydrolysis. CONCLUSION: Oxalate content was significantly related to carbohydrate metabolism, CCI, and protein synthesis. This study significantly contributed to the screening of the sweet potato stress response to drought, to adapt this crop to climatic change through breeding programs. © 2019 Society of Chemical Industry.


Assuntos
Ipomoea batatas/metabolismo , Oxalatos/química , Tubérculos/química , Água/metabolismo , Metabolismo dos Carboidratos , Secas , Ipomoea batatas/química , Oxalatos/metabolismo , Fotossíntese , Brotos de Planta/química , Brotos de Planta/metabolismo , Tubérculos/metabolismo , Amido/análise , Amido/metabolismo , Água/análise
4.
J Ethnopharmacol ; 247: 112152, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31421183

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tropaeolum tuberosum Ruíz & Pavón (Tropaeolaceae). Sim (commonly called Mashua) is an indigenous plant that has medicinal values for various ethnic groups of the regions of the Andes mountain range of South America, which use it for the treatment of diseases venereal, lung and skin; for the healing of internal and external wounds; and as an analgesic for kidney and bladder pain. AIM OF THE REVIEW: We critically summarised the current evidence on the botanic characterisation and distribution, ethnopharmacology, secondary metabolites, pharmacological activities, qualitative and quantitative analysis, and toxicology of T. tuberosum. MATERIALS AND METHODS: The relevant information on T. tuberosum was gathered from worldwide accepted scientific databases via electronic search (Google scholar, Elsevier, SciFinder, ScienceDirect, PubMed, SpringerLink, Web of Science, Scopus, Wiley Online, Mendeley, Scielo and Dialnet electronic databases). Information was also obtained from the literature and books as well as PhD and MSc dissertations. Plant names were validated by 'The Plant List' (www.theplantlist.org). RESULTS: T. tuberosum has diverse uses in local and popular medicine, specifically for relieving pain and infections in humans. Regarding its biological activities, polar extracts (aqueous, hydroalcoholic) and isolated compounds from the tubers have exhibited a wide range of in vitro and in vivo pharmacological effects, including antibacterial, antioxidant, anti-inflammatory activities. Quantitative analysis (e.g., NMR, HPLC, GC-MS) indicated the presence of a set of secondary metabolites, including hydroxybenzoic acids, tannins, flavanols, anthocyanins, glucosinolates, isothiocyanates, phytosterols, fatty acids and alkamides in the tubers of T. tuberosum. Likewise, glucosinolates have been identified in the seeds and isothiocyanates have been detected in leaves, flowers and seeds. CONCLUSIONS: T. tuberosum has been tested for various biological activities and the extracts (tubers in particular) demonstrated a promising potential as an antibacterial, antioxidant, anti-inflammatory and inhibitors of benign prostatic hyperplasia. A lack of alignment between the ethno-medicinal uses and existing biological screenings was observed, indicating the need to explore its potential for the treatment against respiratory affections, urinary affections and blood diseases. Likewise, it is necessary to analyse deeply the relationship that exists between the different tuber colours of T. tuberosum and its use for the treatment of certain diseases. Validation of clinical studies of the antibacterial, antioxidant/anti-inflammatory, anti-spermatogenic activities and as inhibitors of benign prostatic hyperplasia is required. Moreover, studies on the toxicity, bioavailability, and pharmacokinetics, in addition to clinical trials, are indispensable for assessing the safety and efficacy of the active metabolites or extracts obtained from T. tuberosum. Other areas that need investigation are the development of future applications based on their active metabolites, such as neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease). Finally, the work purposes to motivate other research groups to carry out a series of scientific studies that can fill the gaps that exist with respect to Mashua properties, and thus be able to change the focus of T. tuberosum (Mashua) that currently has in the consumer society.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Tropaeolum/química , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Etnofarmacologia , Humanos , Extratos Vegetais/uso terapêutico , Tubérculos/química , América do Sul
5.
Fitoterapia ; 139: 104404, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31676394

RESUMO

Five new cucurbitane-type triterpenoid saponins Xuedanosides A-E (1-5) were isolated from the medicinal plant Hemsleya amabilis Diels by silica gel column, octadecylsilyl (ODS) column, and pre-HPLC techniques. Their structures were determined by spectroscopic analysis and examined alongside existing data from prior studies. Separated compounds were evaluated for their cytotoxic activity in HeLa, HCT-8, MCF-7 and HepG2 human cancer cell lines, and compounds 1 and 2 showed significant effects against HeLa cells with IC50 values of 3.21 and 8.57 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cucurbitaceae/química , Tubérculos/química , Saponinas/farmacologia , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , China , Glicosídeos , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação
6.
BMC Complement Altern Med ; 19(1): 256, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521162

RESUMO

BACKGROUND: Arisaema jacquemontii is traditionally used in treatment of different diseases. In this study, phytochemical, in vitro biological and chemo-preventive screening of A. jacquemontii was carried out to explore its pharmacological potential. METHODS: The dried tuber of A. jacquemontii was extracted in 11 organic solvent mixture of different polarity. The extracts were screened for phytochemical assays (phenolics and flavonoids), antioxidants potential (free radical scavenging activity, total antioxidant activity, reducing power), biological activities (antibacterial, antifungal, cytotoxic, antileishmanial, protein kinase inhibition), and chemopreventive activities using different cell lines through standard protocols. RESULTS: Significant amount phenolic contents were determined in EtOH and MeOH extracts (210.3 ± 3.05 and 193.2 ± 3.15 µg GAE/mg, respectively). Maximum flavonoid content was determined in MeOH extract (22.4 ± 4.04 µg QE/mg). Noteworthy, DPPH scavenging activity was also recorded for MeOH extract (87.66%) followed by MeOH+EtOAc extract (85.11%). Considerable antioxidant capacity (7.8 ± 0.12 µg AAE/mg) and reducing power (3.1 ± 0.15 µg AAE/mg) was observed in extract of MeOH. The LC50 against brine shrimp and leishmanial parasite was found 9.01 and 12.87 µg/mL for n-Hex and CHCl3 extracts, respectively. The highest zone of inhibition against Streptomyces hyphae formation (12.5 ± 1.77 mm) by n-Hex extract. Growth zone of inhibition 13.8 ± 1.08 mm was recorded for EtOAc and MeOH extracts, respectively against Micrococcus luteus while 10.0 ± 0.11 mm for MeOH extract against Aspergillus flavus. In-vitro cytotoxic assay showed that n-Hex extract had higher cytotoxicity against DU-145 prostate cancer and HL-60 cancer cell lines. NF-kB and MTP potential showed 34.01 and 44.87 µg/mL for n-Hex and CHCl3 extracts, respectively in chemo-preventive potential. CONCLUSION: The study concludes that Arisaema jacquemontii bears significant phytochemical activity and pharmacological activities, this plant can be further explored for isolation of active component against a number of aliments.


Assuntos
Anti-Infecciosos/química , Arisaema/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Artemia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Tubérculos/química
7.
J Agric Food Chem ; 67(41): 11542-11552, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31538781

RESUMO

Two field trials were conducted to investigate the influence of fungicide and fertilization management on the potato tubers' metabolome (Solanum tuberosum L.). Thereby, fungicides and conventional fertilizers were varied in terms of quantities, number and date of applications, physical state, and product composition. Following a water-methanol-based extraction, samples were analyzed using an UPLC-IMS-QToF and multivariate data analysis. Fungicide application led to significant changes in the tubers' metabolome. Flavonoids were increasingly expressed as a natural response to impending fungal or viral infections in an untreated group, while the phytoalexin rishitinol was highly abundant in groups with fungicide application. In contrast to fungicides, the application of conventional fertilizers did not cause significant alterations in the tubers' compound composition. Consequently, the impact of fungicide application could be rated as more important than the fertilization-derived influence, which might be because of a gentler adaption to fertilization than to the acute stress of fungicide applications.


Assuntos
Produção Agrícola/métodos , Fertilizantes/análise , Fungicidas Industriais/farmacologia , Espectrometria de Massas/métodos , Tubérculos/química , Solanum tuberosum/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Metaboloma , Tubérculos/efeitos dos fármacos , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Solanum tuberosum/química , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo
8.
J Mol Model ; 25(9): 295, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478108

RESUMO

Cyanogenesis is an enzyme-promoted cleavage of ß-cyanoglucosides; the release of hydrogen cyanide is believed to produce food poisoning by consumption of certain crops as Cassava (Manihot esculenta Crantz). The production of hydrogen cyanide by some disruption of the plant wall is related to the content of two ß-cyanoglucosides (linamarin and lotaustralin) which are stored within the tuber. Some features about the mechanistic bases of these transformations have been published; nevertheless, there are still questions about the exact mechanism, such as the feasibility of a difference in the kinetics of cyanogenesis between both cyanoglucosides. In this work, we have performed a theoretical analysis using DFT and QTAIM theoretical frameworks to propose a feasible mechanism of the observed first step of the enzyme-catalyzed rupture of these glucosides; our results led us to explain the observed difference between linamarin and lotaustralin. Meanwhile, DFT studies suggest that there are no differences between local reactivity indexes of both glucosides; QTAIM topological analysis suggests two important intramolecular interactions which we found to fix the glucoside in such a way that suggests the linamarin as a more reactive system towards a nucleophilic attack, thus explaining the readiness to liberate hydrogen cyanide.


Assuntos
Glucosídeos/química , Cianeto de Hidrogênio/química , Manihot/química , Nitrilos/química , Biocatálise , Biotransformação , Glucosídeos/metabolismo , Cianeto de Hidrogênio/metabolismo , Cinética , Manihot/enzimologia , Estrutura Molecular , Nitrilos/metabolismo , Tubérculos/química , Tubérculos/enzimologia , Teoria Quântica , Termodinâmica
9.
Fitoterapia ; 138: 104350, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473333

RESUMO

Three new bibenzyl derivatives (bletstrins A-C, 1-3), including two bibenzyls that have hydroxyl-substituted chiral centers on the aliphatic bibenzyl bridge, along with eighteen known stilbenoids (4-21) were isolated from the tubers of Bletilla striata. The structures of new compounds were elucidated by the use of 1D/2D NMR spectroscopic data. The absolute configurations of bletitrins A and B were determined by optical rotation value. Compounds 13-16 were isolated from the Orchidaceae for the first time. Most of the isolated compounds were evaluated for their antibacterial activities against three gram-positive bacterial strains and one gram-negative bacterial strain. Compounds 4, 10, 12, 14, 15, 16 and 18 showed potent inhibitory activities, with MICs of (6-52 µg/mL) against S. aureus ATCC 6538.


Assuntos
Antibacterianos/farmacologia , Orchidaceae/química , Tubérculos/química , Estilbenos/farmacologia , Antibacterianos/isolamento & purificação , Bibenzilas/isolamento & purificação , Bibenzilas/farmacologia , China , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Estilbenos/isolamento & purificação
10.
Molecules ; 24(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510058

RESUMO

Phenolic acids including chlorogenic acids are major polyphenolic compounds found in Jerusalem artichoke (Helianthus tuberosus L.). The plant itself is an emerging biorefinery crop due to the inulin-rich tubers, a bioethanol feedstock, but the aerial parts represent a rich source of bioactive compounds. We have determined the level of major phenolic acids in extracts of four plant organs: tuber, leaf, flower, and stem. Employing three heating conditions (20 °C, 60 °C, and microwaving), corrected total phenolic content (TPC) was highest in the leaves (4.5-5.7 mg gallic acid equivalents g-1 dry substance), followed by flower (2.1-2.9), tuber (0.9-1.4), and lowest in stem extracts (0.1-0.2). A previously overlooked interference of the Folin-Ciocalteu assay, namely a signal contribution from ascorbic acid, caused overestimation of TPC in various organs ranging from 65% to 94%. Radical scavenging activity of extracts correlated significantly with TPC, both on corrected (R2 = 0.841) and uncorrected (R2 = 0.884) values. Out of the identified phenolic acids determined by quantitative HPLC-UV analysis, chlorogenic and dicaffeoylquinic acids accounted for 72-82% of corrected TPC in leaf and tuber extracts. Optimization of leaf extraction was tested in a 23-factorial Central Composite Face (CCF) design. Temperature was the most important model term, and a solvent strength of less than 50% ethanol promoted the highest TPC yields. Further developments in extraction processing of crop residues may open avenues for improving the utilization of Jerusalem artichoke in valuable products.


Assuntos
Antioxidantes/química , Helianthus/química , Hidroxibenzoatos/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Hidroxibenzoatos/farmacologia , Fenóis/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Tubérculos/química , Solventes/química , Temperatura Ambiente
11.
J Dairy Sci ; 102(10): 8691-8695, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421885

RESUMO

Potato pectin has unique molecular characteristics that differentiate it from commercially available pectins sourced from citrus peels or apple pomace, including a higher degree of branching and a higher acetyl content. The objective of this study was to evaluate the ability of potato pectin to stabilize milk proteins at an acidic pH above their isoelectric point, pH 5.5, at which no citrus- or apple-derived pectins are functional. Potato pectin was extracted from raw potato tubers by heating at pH 4.5 and 120°C for 30 min after removing starch solubilized using a dilute HCl solution adjusted to pH 2. The potato pectin was found to have a galacturonic acid content of 17.31 ± 3.29% (wt/wt) and a degree of acetylation of 20.20 ± 0.12%. A portion of the potato pectin was deacetylated by heating it in an alkaline condition. The deacetylation resulted in a galacturonic acid content of 19.12 ± 4.64% (wt/wt) and a degree of acetylation of 3.03 ± 0.03%. Particle size distributions in acidified milk drink (AMD) samples adjusted to pH 5.5 demonstrated that the acetylated and deacetylated potato pectins were capable of inhibiting the aggregation of milk proteins to the largest degree at a pectin concentration of 1.0 and 0.25% (wt/wt), respectively. Pectin molecules that were not bound to milk proteins in these AMD samples were quantified after centrifugally separating milk proteins and pectin bound to them from the serum. We found that, for the acetylated and deacetylated potato pectins, all or approximately half of the pectin molecules were bound to milk proteins at a pectin concentration of 0.25 or 1.0% (wt/wt), respectively. These results suggest that the presence of acetyl groups is a critical factor that determines how potato pectin molecules bind electrostatically to milk protein surfaces, form 3-dimensional structures there, and function as a stabilizer. The present results demonstrate that potato pectin can stabilize milk proteins at pH 5.5 and potentially enable the development of novel AMD products with improved functionality for casein-containing products with moderately acidic pH profiles.


Assuntos
Proteínas do Leite/química , Pectinas/química , Solanum tuberosum/química , Animais , Caseínas/análise , Ácidos Hexurônicos/análise , Concentração de Íons de Hidrogênio , Leite/química , Tubérculos/química , Polissacarídeos/química , Estabilidade Proteica
12.
J Agric Food Chem ; 67(29): 8197-8204, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31287317

RESUMO

Potato pectin contains some proteinaceous components and exhibits emulsifying and emulsion stabilizing abilities. The objective of this study was to elucidate the effect of the pectin moiety of the pectin-protein conjugate present in pectic extracts from potato tubers on their interfacial properties. Potato pectin was extracted from highly purified cell wall materials to avoid the contamination of unconjugated proteins. The abilities of the potato pectin to adsorb to graphite surfaces and to resist surfactant-induced competitive displacement from the air-water interface were investigated using atomic force microscopy. The pectin moiety of the potato pectin was capable of adsorbing to graphite surfaces even after alkali treatment. Furthermore, the potato pectin exhibited enhanced resistance to surfactant-induced competitive displacement from the interface as a result of the formation of network structures of self-assembled pectin moieties at the interface. The present results suggest the importance of the pectin moiety with regard to the interfacial properties of potato pectin.


Assuntos
Pectinas/química , Extratos Vegetais/química , Proteínas de Plantas/química , Solanum tuberosum/química , Tensoativos/química , Ar/análise , Tubérculos/química , Água/química
13.
J Agric Food Chem ; 67(28): 8053-8060, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31276393

RESUMO

The development of analytical methods for acrylamide formed during food processing is of great significance for food safety, but limited by its inherent characteristics, the analysis of acrylamide is a continuing challenge. In this study, an efficient derivatization strategy for acrylamide based on thiol-ene click reaction with cysteine as derivatization reagent was proposed, and the resulting derivative was then analyzed by capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D). After systematic investigation including catalyst dosage (0-20 mM), reaction temperature (30-90 °C) and time (1-60 min), and cysteine concentration (0.2-3.6 mM), acrylamide could be efficiently labeled by 2.0 mM cysteine at 70 °C for 10 min using 4 mM n-butylamine as catalyst. Application of 10 mM triethylamine as separation buffer, the labeled acrylamide was analyzed within 2.0 min, and the relative standard deviations of migration time and peak area were less than 0.84% and 5.6%, indicating good precision. The C4D signal of acrylamide derivative showed a good linear relationship with acrylamide concentration in the range of 7-200 µM with the correlation coefficient of 0.9991. The limit of detection and limit of quantification were calculated to be 0.16 µM and 0.52 µM, respectively. Assisted further by the QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample pretreatment, the developed derivatization strategy and subsequent CE-C4D method were successfully applied for the determination of acrylamide in potato products.


Assuntos
Acrilamida/análise , Química Click/métodos , Eletroforese Capilar/métodos , Solanum tuberosum/química , Culinária , Cisteína/química , Temperatura Alta , Limite de Detecção , Tubérculos/química
14.
J Sci Food Agric ; 99(14): 6572-6581, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31325328

RESUMO

BACKGROUND: As a pretreatment before drying, the purpose of osmotic dehydration (OD) is to reduce the initial water content of samples and shorten the drying time. When OD is combined with pulse vacuum, the mass transfer is enhanced. Furthermore, the properties of materials, which affect the absorption and dissipation of microwaves, can be changed by OD. In this work, pulsed vacuum osmotic dehydration (PVOD) with sucrose solution was adopted before microwave freeze-drying (MFD). The effects of PVOD on the drying characteristics and quality of dried products were studied. RESULTS: Results showed that the unfrozen water content was increased by PVOD, which made the dielectric constant and loss factor of Chinese yam larger than that of untreated samples, and the difference amplified with the increasing temperature. Thus, the shortened drying time (up to 38.5%) and increased average drying rate (up to 16.8%) were achieved by MFD combined with PVOD. While in traditional freeze-drying, PVOD resulted in slightly shortened drying time but decreased drying rate. The mechanism of PVOD on improving drying rate of MFD was analyzed from the perspective of unfrozen water content and dielectric properties. Furthermore, the quality assessments indicated that PVOD treatment retained a better color and improved the total phenolic content of dried yams compared to untreated and dried samples. CONCLUSION: PVOD using sucrose solution was an effective method to change the characteristics of yam, enhancing the MFD rate and improving the product qualities. © 2019 Society of Chemical Industry.


Assuntos
Dessecação/métodos , Dioscorea/química , Conservação de Alimentos/métodos , Tubérculos/química , Água/análise , Cor , Dessecação/instrumentação , Conservação de Alimentos/instrumentação , Liofilização , Micro-Ondas , Osmose , Fenóis/análise
15.
Food Funct ; 10(9): 5312-5322, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31353387

RESUMO

Modulation of the starch digestion rate and extent is a major target for increasing nutritional value of potato-based food. In order to understand the effect of controlled gelatinization on the structure and in vitro digestion properties of whole potato food, intact parenchyma cells were isolated as a model through soaking in mild acid and alkali solutions, and then hydrothermally treated at different incubation temperatures in excess water. The morphological and structural changes of entrapped starch granules as well as in vitro starch digestion properties were investigated. Three classes of starch digestion of potato cells are identified: (1) when the temperature of hydrothermal treatment was set at 55 °C or 60 °C, the efficient physical barrier of intact cell walls resulted in a limited starch digestion extent; (2) when the temperature is set at 65 °C, the cell wall structures apparently reduced the digestion rate but only slightly reduced the final extent compared to the starch counterpart, probably because starch swelling weakens the physical barrier; (3) at 70-95 °C, the damaged cell wall still reduced the digestion rate but did not reduce the digestion extent compared to the starch counterpart. The results suggest that controlling hydrothermal processing temperature is a viable approach to develop potato ingredients with enhanced nutritional functionality.


Assuntos
Solanum tuberosum/metabolismo , Amido/química , Água/análise , Culinária , Digestão , Temperatura Alta , Humanos , Modelos Biológicos , Tubérculos/química , Tubérculos/metabolismo , Solanum tuberosum/química , Amido/metabolismo , Temperatura Ambiente , Água/metabolismo
16.
Environ Monit Assess ; 191(7): 424, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31183582

RESUMO

Honey is a nutritive fluid product of bees with an array of pharmacological/medicinal effects. As a natural product from honeybees, honey is regarded to be safe and free from any contaminants. Cassava tuber (Manihot esculenta)-based meal, Vernonia amygdalina (bitter leaf soup), and honey are common local cuisine in Nigeria. This is a human health risk assessment of heavy metals associated with the consumption of honey (Apis mellifera scutellata), cassava (Manihot esculenta), and bitter leaf (Vernonia amygdalina) in Enugu State, Nigeria. Concentrations of lead (Pb), Cd, As, Cu, Ni, Mn, Fe, Cr, and Fe in honey, soil, Manihot esculenta, and Vernonia amygdalina were determined using an atomic absorption spectrophotometer (AAS). The principal component analysis (PCA) was performed as a factor reduction technique among 12 factors (3 locations against 4 sources of heavy metals). The mean concentration of metals in honey, soil, Manihot esculenta, and Vernonia amygdalina ranged from 0.001 to 4.28 mg kg-1, from 0.0026 to 170.52 mg kg-1, from 0.012 to 80.63 mg kg-1, and from 0.0016 to 126.48 mg kg-1, respectively. Pb showed the highest carcinogenic risk with values of 3.18E-04-1.43E-01 in Vernonia amygdalina and 1.69E-04-3.47E-04 in Manihot esculenta for adults and children, respectively. In honey, Cd showed the highest carcinogenic risk with values of 1.26E-02-1.07E-01. About 51.5% of total cancer risk (TCR) was below 1E-04. Consumption of honey, Vernonia amygdalina, and Manihot esculenta in some urban parts of Enugu may pose some adverse health effects.


Assuntos
Arsênico/análise , Carcinógenos/análise , Mel/análise , Manihot , Metais Pesados/análise , Poluentes do Solo/análise , Vernonia , Adulto , Animais , Criança , Monitoramento Ambiental , Humanos , Nigéria , Folhas de Planta/química , Tubérculos/química , Medição de Risco
17.
J Sci Food Agric ; 99(14): 6227-6233, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250922

RESUMO

BACKGOUND: Potato peels are usually discarded before consumption of the tubers. However, it could be expected that red- and purple-fleshed potato peels contain more minerals. Therefore, the purpose of the study was to evaluate and compare the proximate and mineral composition in flesh and peels of six coloured potato cultivars. Five proximate compositions (dry matter, total soluble solids, protein, fibre, and ash) and nine minerals [phosphorus (P), calcium (Ca), magnesium (Mg), potassium (K), iron (Fe), zinc (Zn), copper (Cu), Boron (B), manganese (Mn)] content were determined. The data obtained were evaluated employing the multivariate analysis techniques: principal component analysis and hierarchical cluster analysis. RESULTS: The results show that proximate and mineral composition depends on potato tissue and cultivar. Potato peels have significantly higher levels of protein, fibre, ash and minerals (except Mg) than the flesh. However, flesh contains the highest contents of dry matter and total soluble solids. Of the studied elements, K has the highest content in both parts of the potato tuber followed by P, Mg, Ca, Fe, Zn, B, Mn, and Cu. Violetta peels had the highest contents of ash, K and Mg, and Highland Burgundy Red peels had the highest protein, fibre, Ca, Mn contents. The flesh of the Highland Burgundy Red cultivar shows the highest contents of dry matter and total soluble solids. CONCLUSION: Based on the present study, it can be concluded that the investigated red and purple potato peels showed significantly higher protein, fibre, ash and element (K, Ca, Mg, P, Fe, Cu, Zn, Mn, B) contents compared to the flesh. © 2019 Society of Chemical Industry.


Assuntos
Minerais/química , Tubérculos/química , Cor , Cobre/análise , Ferro/análise , Magnésio/análise , Manganês/análise , Fósforo/análise , Potássio/análise , Solanum tuberosum/metabolismo , Zinco/análise
18.
Plant Foods Hum Nutr ; 74(3): 350-357, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31209702

RESUMO

Thirteen fruits, eight legumes and three tubers consumed in the Andean regions of Ecuador were studied to determine their bioactive compounds, organic acids, sugars content, total antioxidant capacity, as well as to determine which among them showed the greatest contribution in terms of antioxidant activity and which compounds contributed to it. Among fruits, taxo fruits (Passiflora mollissima (Kunth) L.H. Bailey) presented the highest values of total phenolic, carotene content, and total antioxidant capacity. The ají ratón (Capsicum chinense Jacq) showed the highest content of vitamin C. Taxo showed the highest content of ß carotene, whilst lycopene was identified only in guayaba fruits (Psidium guajava L.) and ají ratón was the principal source of lutein. In legumes, chocho perla (Lupinus mutabilis Sweet) showed the highest values for both total phenolic and flavonoid content, whilst frejol negro (Phaseolus vulgaris L.) and frejol canario (Vigna unguiculata (L.) Walp) showed the highest values for FRAP and DPPH assay, respectively. Between tubers, the jícama (Smallanthus sonchifolius (Poepp.) H. Rob.) had the majors values in terms of total phenolic, flavonoid content, and total antioxidant capacity. In terms of total antioxidant capacity, taxo fruits have the highest contribution in terms of total antioxidant capacity, whilst the dendogram shown the occurrence of five distinct groups in which taxo was located in the first largest group. Our data contributing towards gaining better knowledge about the Andean Ecuadorian diet and the composition of Andean food in order to estimate dietary intakes of health-promoting components.


Assuntos
Antioxidantes/análise , Asteraceae/química , Capsicum/química , Fabaceae/química , Promoção da Saúde , Passiflora/química , Ácido Ascórbico/análise , Carotenoides/análise , Equador , Flavonoides/análise , Frutas/química , Fenóis/análise , Compostos Fitoquímicos/análise , Tubérculos/química , beta Caroteno/análise
19.
Biomed Res Int ; 2019: 8939854, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31111071

RESUMO

Sweet potato (Ipomoea batatas L. Lam.), known as "Shakarqandi" in Pakistan, is an imperative root vegetable with large size, traditionally used as aphrodisiac, antiprostatic, anti-inflammatory, antidiabetic, cardiotonic, and anticancer agent. Present study was conducted to gauge aphrodisiac potential of Ipomoea batatas ethyl acetate (IPT-EA, IPA-EA) and methanol (IPT-M, IPA-M) extracts from tuber and aerial part, respectively, via behavioral and biochemical tests and their possible protective role in BPA-induced gonadotoxicity at the dose 300 mg/kg in male Sprague Dawley rats. Phytochemical analysis was done qualitatively and quantitatively through total phenolic and flavonoid content (TPC and TFC) and high performance liquid chromatographic (HPLC-DAD) fingerprinting while antioxidant profiling used multimode in vitro assays. To calculate sexual excitement mount latency, intromission latency, mount frequency, intromission frequency, ejaculatory latency, and postejaculatory interval were examined while for biochemical ratification semen characteristics, levels of testosterone, follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol were measured. Gonadoprotective ability was assessed through comet assay and histomorphological examination of testes. Qualitative analysis ensured the presence of phenols, flavonoids, tannins, anthocyanin, saponins, coumarins, terpenoids, and betacyanin. Quantitatively maximal TPC (304.32±7.20 µg GAE/mg dry extract) and TFC (214.77±4.09 µg QE/mg DE) were estimated in IPA-EA extract. IPT-EA yielded maximum rutin (7.3±0.12) and myricetin (2.7±0.14 µg/mg DE) while IPA-EA and IPA-M yielded maximum caffeic acid (4.05±0.22 and 1.92±0.17 µg/mg DE, respectively) in HPLC-DAD analysis. Extracts enhanced sexual excitement, improved semen quality, levels of testosterone, FSH, LH, and estradiol, and successfully attenuated toxic effects of BPA. Levels of endogenous antioxidant enzymes (CAT, SOD, POD, and GSH) were restored and NO abundance was minimized. Significant stimulation in sexual behavior, amelioration of toxicity symptoms, elevated spermatic production, raised viability, vitalized levels of gonadal hormones, maintained endogenous enzymes, genoprotection, and reformed testicular histology endorsed I. batatas as a better aphrodisiac alternative and gonadoprotective agent.


Assuntos
Afrodisíacos/farmacologia , Compostos Benzidrílicos/efeitos adversos , Ipomoea batatas/química , Medicina Tradicional/métodos , Fenóis/efeitos adversos , Extratos Vegetais/farmacologia , Testículo/efeitos dos fármacos , Animais , Antioxidantes/química , Comportamento Animal , Cromatografia Líquida de Alta Pressão , Feminino , Flavonoides/química , Hormônios Gonadais , Masculino , Modelos Animais , Paquistão , Fenóis/química , Compostos Fitoquímicos/farmacologia , Tubérculos/química , Ratos , Ratos Sprague-Dawley , Análise do Sêmen , Comportamento Sexual Animal/efeitos dos fármacos , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Testículo/patologia
20.
Phytochemistry ; 162: 216-223, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30953908

RESUMO

Ten previously undescribed bibenzyl derivatives (bletistrins A-J), including 5 that have hydroxyl-substituted chiral centres on the aliphatic bibenzyl bridge, along with twelve known bibenzyl derivatives, were isolated from the rhizomes of Bletilla striata. The structures of bletistrins A-J were primarily elucidated on the basis of their 1D and 2D NMR spectroscopic data. The absolute configurations of bletistrins A, D, F, H and I were determined by electronic circular dichroism (ECD) spectroscopic analysis and optical rotation value. Most of the isolated compounds were evaluated for their antibacterial activities against 3 g-positive bacterial strains and 1 g-negative bacterial strain. Bletistrins F, G, and J, bulbocol, shanciguol and shancigusin B showed inhibitory activities, with MICs of (3-28 µg/mL) against S. aureus ATCC 6538.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bibenzilas/química , Bibenzilas/farmacologia , Orchidaceae/química , Tubérculos/química , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Staphylococcus aureus/efeitos dos fármacos
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