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1.
Food Res Int ; 178: 113970, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309916

RESUMO

Yam bean is an important source of dietary fiber and other components that comprise the total indigestible fraction (TIF), which can be fermented by the colonic microbiota and produce metabolites with beneficial health effects. Therefore, the objective of this study was to evaluate the in vitro colonic fermentation of yam bean TIF and the changes caused by the addition of a polyphenolic extract of mango seed and the lactic acid bacteria Pediococcus acidilactici. The mango seed extract was obtained by ultrasound-assisted extraction, and the microbial growth rate and viability of P. acidilactici were determined using a Neubauer chamber. Yam bean TIF was isolated by triple enzymatic hydrolysis and subjected to in vitro colonic fermentation in combination with treatments with mango seed extract and P. acidilactici suspensions. Changes in pH, total soluble phenols (TSP), and antioxidant capacity (AOX) were evaluated. Furthermore, the production of metabolites was quantified by HPLC-DAD-MS and GC-MS. The Growth rate of P. acidilactici was 0.1097 h-1 with 97.5 % viability at 7 h of incubation. All TIF treatments showed a high capacity of fermentation, and the addition of mango seed extract increased the TSP content and AOX in DPPH and FRAP assays. A total of Forty-six volatile metabolites were detected, with highlighting the presence of esters, benzenes, aldehydes, and short-chain fatty acids. Five phenolic compounds associated with mango by-products were quantified during all fermentation process, despite the concentration of the extract. P. acidilactici did not substantially modify the fermentative profile of TIF. However, further studies such as the evaluation of the abundance of microbial communities may be necessary to observe whether it can generate changes during colonic fermentation.


Assuntos
Mangifera , Pachyrhizus , Pediococcus acidilactici , Polifenóis/farmacologia , Fermentação , Mangifera/química , Fenóis/análise , Sementes/química , Extratos Vegetais/farmacologia
2.
Int J Biol Macromol ; 258(Pt 2): 129095, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158067

RESUMO

Starch attracts food industries due to their availability in nature, cheapness, biodegradability and possibilities of endless applications. The starch properties and their modification affect food quality. Compared to other cereals, tuber and root starches, more systematic information is needed on the jicama starches (JS). This review article summarizes the isolation, composition, morphology, rheological, thermal and digestibility properties of JS. The modifications and its current and potential applications are also discussed. The chemical composition and structure of JS are different from other starches, influencing its properties. JS has been modified by physical and chemical methods to improve the properties of starch. However, there are very few studies on the modification of JS as compared with other commercial starch although it has been used in food formulation as a stabilizer and to improve the texture of food products. It is also applied as an edible coating to preserve the quality of food products and use as a raw material for making edible and bioplastic packaging. However, large-scale utilization of JS is unexplored compared to commercial starches. Therefore, this review would provide useful information and suggestions for more research on Jicama starch and its industrial applications.


Assuntos
Pachyrhizus , Amido , Amido/química , Verduras , Grão Comestível , Indústria Alimentícia
3.
Plant Dis ; 107(5): 1617-1619, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37170421

RESUMO

Pseudomonas bijieensis is a newly established species with antifungal activity. Here, we report the high-quality and complete genome sequence for P. bijieensis strain SP1, created by hybrid assembly using both short reads and long reads. The length of the circular chromosome is about 6.67 Mb, with a GC content of 60.89%. Bioinformatic analyses revealed gene clusters for the biosynthesis of antimicrobial metabolites 2,4-diacetylphloroglucinol as well as bacterial secretion systems (type I to III and type V to VI). Interestingly, this strain can cause soft rot symptoms in the roots of yam bean, showing the potential to be a plant pathogen. The genomic data will be a valuable resource for exploring the virulence mechanism and antifungal activity of this strain.


Assuntos
Pachyrhizus , Pseudomonas , Pseudomonas/genética , Pachyrhizus/genética , Antifúngicos , Virulência , Genoma Bacteriano/genética
5.
J Gen Appl Microbiol ; 68(5): 225-231, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35691844

RESUMO

The present study investigated the efficacy of bacterial cellulose production by K. xylinus TISTR 1011 and K. nataicola TISTR 975 using yam bean juice as a nutrient source, and the physicochemical and sensory characteristics of bacterial cellulose were examined. Bacterial cellulose content, production yield, and production rate were significantly higher when K. xylinus TISTR 1011 rather than K. nataicola TISTR 975 was used as the bacterial strain. The analysis of physicochemical characteristics revealed that bacterial cellulose produced by K. xylinus TISTR 1011 using yam bean juice medium had higher scores for CIE L*, a*, and b* values, wet weight, moisture content, firmness, and gel strength than bacterial cellulose produced by K. nataicola TISTR 975. In contrast, sensory evaluation showed that the acceptability scores and preference of all attributes of bacterial cellulose produced by K. nataicola TISTR 975 using yam bean juice medium were higher than those of bacterial cellulose produced by K. xylinus TISTR 1011. The results of this study indicate that yam bean juice from yam bean tubers, an alternative raw material agricultural product, can be used as a nutrient source for producing bacterial cellulose or nata by Komagataeibacter strains.


Assuntos
Acetobacteraceae , Pachyrhizus , Celulose , Nutrientes
6.
PLoS One ; 17(7): e0270534, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35867657

RESUMO

Plants are constantly threatened by a virus infection, i.e., Potyviruses, the second largest genus of plant viruses which results in several million-dollar losses in various essential crops globally. Yam bean (Pachyrhizus erosus) is considered to be one of the essential tuberous legume crops holding a great potential source of starch. Yam Bean Mosaic Virus (YBMV) of Potyvirus group belonging to the family potyviridae affects Yam bean and several angiosperms both in the tropical and sub-tropical regions causing large economical losses in crops. In this study, we attempted to understand the sequence-structure relationship and mode of RNA binding mechanism in YBMV CP using in silico integrative modeling and all-atoms molecular dynamics (MD) simulations. The assembly of coat protein (CP) subunits from YBMV and the plausible mode of RNA binding were compared with the experimental structure of CP from Watermelon mosaic virus potyvirus (5ODV). The transmembrane helix region is present in the YBMV CP sequence ranging from 76 to 91 amino acids. Like the close structural-homolog, 24 CPs monomeric sub-units formed YBMV a conserved fold. Our computational study showed that ARG124, ARG155, and TYR151 orient towards the inner side of the virion, while, THR122, GLN125, SER92, ASP94 reside towards the outer side of the virion. Despite sharing very low sequence similarity with CPs from other plant viruses, the strongly conserved residues Ser, Arg, and Asp within the RNA binding pocket of YBMV CP indicate the presence of a highly conserved RNA binding site in CPs from different families. Using several bioinformatics tools and comprehensive analysis from MD simulation, our study has provided novel insights into the RNA binding mechanism in YBMV CP. Thus, we anticipate that our findings from this study will be useful for the development of new therapeutic agents against the pathogen, paving the way for researchers to better control this destructive plant virus.


Assuntos
Fabaceae , Pachyrhizus , Potyvirus , Biologia Computacional , Fabaceae/genética , Humanos , Pachyrhizus/química , Pachyrhizus/genética , Potyvirus/genética , RNA Viral/genética
7.
Probiotics Antimicrob Proteins ; 14(5): 884-903, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35710863

RESUMO

The increasing mortality due to hypertension and hypercholesterolemia is directly linked with type-2 diabetes. This shows the lethality of the disease. Reports suggest that the prebiotics along with probiotics help in lowering the effects of type-2 diabetes. Prebiotic like inulin is best known for its anti-diabetic effect. The current study utilizes jicama extract as prebiotic source of inulin along with the bacterial strains with probiotic properties (Lactiplantibacillus plantarum and Enterococcus faecium) for treating type-2 diabetes in high-fat diet-induced Drosophila melanogaster model. The high-fat diet-induced Drosophila showed deposition of lipid droplets and formation of micronuclei in the gut. The larva and adult treated with probiotics and synbiotic (probiotic + prebiotic- inulin) comparatively reduced the lipid deposition and micronuclei number in the gut. The increased amount of triglyceride in the whole body of the fatty larva and adult indicated the onset of diabetes. The overexpression of insulin-like genes (Dilp 2) and (Dilp 5) confirmed the insulin resistance, whereas the expression was reduced in the larva and adult supplemented with probiotics and synbiotic. The reactive oxygen species level was reduced with the supplementation of probiotics. The weight, larva size, crawling speed and climbing were also altered in high-fat diet-induced Drosophila melanogaster. The study confirmed the effects of probiotics and synbiotic in successfully lowering diabetes in Drosophila. The study also proved the anti-diabetic potential of the probiotics. Further, it was also confirmed that the probiotics work better in the presence of prebiotic.


Assuntos
Diabetes Mellitus Tipo 2 , Pachyrhizus , Probióticos , Simbióticos , Animais , Dieta Hiperlipídica/efeitos adversos , Drosophila melanogaster , Inulina , Prebióticos , Probióticos/farmacologia
8.
Inflammopharmacology ; 30(6): 2139-2144, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35467241

RESUMO

Gastroprotective is an effect caused by the compounds that have the capability of protecting the gastric mucosa. Peperomia pellucida L. plants contain alkaloids, flavonoids, saponins, tannins, and terpenoids, while Pachyrhizus erosus L. contains flavonoids, alkaloids, tannins, and saponins. Peperomia pellucida L. reportedly contains dillapiole compounds with a gastroprotective effect. Moreover, its isolation result from Pachyrhizus erosus L. indicates the presence of dulcitol, gentisic acid, and formononetin, which has antioxidant activity. This study aims to determine the gastroprotective effect of the combination of Peperomia pellucida L. and Pachyrhizus erosus L. extract on rats with gastric ulcer models by looking at the ulcer index, percentage of inhibition, and histopathology. The research method used in this study was by making a combination of Peperomia pellucida L. and Pachyrhizus erosus L. extract. The combined extract was then given to five treatment groups. Group I as a negative control, group II as a positive control was given sucralfate, groups III, IV, and V were given a combination of Peperomia pellucida L. and Pachyrhizus erosus L. extract of 100, 200, and 400 mg/kg BW. The treatment was given orally for 14 days, after 1 h of treatment on the 14th day, 96% ethanol induction was given orally at a dose of 5 mg/kg BW. The animal dissection was performed 24 h after the induction. The results from observations showed an increase in body weight before and after the treatment. The ulcer index produced by negative control, positive control in the treatment with doses of 100, 200, and 400 were 4.18; 2.98; 2.42; 2.04; and 1.07. This study showed that the combination of Peperomia pellucida L. and Pachyrhizus erosus L. extract has a gastroprotective effect.


Assuntos
Antiulcerosos , Pachyrhizus , Peperomia , Saponinas , Ratos , Animais , Etanol , Úlcera/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Taninos/farmacologia , Flavonoides/farmacologia , Saponinas/farmacologia , Antiulcerosos/farmacologia
9.
Int J Biol Macromol ; 209(Pt A): 597-607, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398390

RESUMO

The objective of this study was to determine the properties of natural jicama starch and edible film made from the starch. The film was prepared by adding agarwood aetoxylon bouya essential oil and calcium propionate to investigate its properties as an edible coating for fruit or vegetables. The microstructure of the edible film was observed using scanning electron microscopy. The three main materials mostly had significant effects (P < 0.05) on the properties of the sample films, and starch film incorporating essential oil­calcium propionate showed optimum properties as an edible coating material because it had the highest elongation of 10.81%, the lowest stiffness with a Young's modulus of about 2.53 MPa, the lowest of water vapor transmission rate and permeability of 0.117 g h-1 m-2 and 3.092 g mm h-1 m-2 kPa-1, respectively, and the lowest weight loss of 75.30%. It was also found that the microstructure of starch-essential oil­calcium propionate film had a homogeneous surface and the presence of essential oil droplets was not visible.


Assuntos
Filmes Comestíveis , Óleos Voláteis , Pachyrhizus , Embalagem de Alimentos , Permeabilidade , Propionatos , Amido/química , Resistência à Tração , Verduras
10.
Food Chem ; 382: 132413, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35152019

RESUMO

Jicama is a widely cultivated but unexploited crop. This study isolated and characterized polysaccharide from roots of Pachyrhizus erosus (PEP). Optimal extraction conditions were obtained using single-factor experiment and response surface methodology, after which an extraction rate of 41.55% was obtained. Contents of total sugar, uronic acid, moisture, and ash were about 85.24%, 10.82%, 1.55%, and 0.05%, respectively. PEP had relative molecular mass of 18.3 kDa and tangled filaments and loose flaky structure. PEP was thermostable and presented high oil holding capacity but relatively low emulsion properties. Rheological tests indicated that the viscosity of PEP was of concentration and temperature dependence. Salt additions at various concentrations caused only slight increase of viscosity and storage modulus. In a word, PEP from jicama was a type of acidic polysaccharide with high thermostability and oil holding capacity. However, emulsion properties and viscosity are relatively low. Fine chemical structure and bio-function of PEP need further investigations.


Assuntos
Pachyrhizus , Raízes de Plantas/química , Polissacarídeos/química , Reologia , Viscosidade
11.
Chem Pharm Bull (Tokyo) ; 69(11): 1136-1139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34719597

RESUMO

A phytochemical investigation of methanol extract from leaves of Pachyrhizus erosus (L.) Urban, a leguminous shrub distributed in Vietnam and other tropical and subtropical countries led to the isolation of a new prenylated chalcone, erosusone (1) and a new megastigmane glycoside epimer, 3-episedumoside F1 (9), together with thirteen known compounds including flavonoids (2-6), a 3-benzoxepine lactone (7), a pyridine-4,5-diol derivative (8), megastigmanes and megastigmane glycosides (10-15). Their structures were elucidated by means of high resolution-electrospray ionization (HR-ESI)-MS, one dimensional (1D) and two-dimensional NMR (2D-NMR) spectroscopy as well as comparison with the data reported in the literature. The cytotoxic effects on LU-1 (lung carcinoma), HepG2 (hepatocellular carcinoma), and MCF7 (breast carcinoma) cell lines were assessed. Prenylated chalcones 1-2 and isoflavone 3 exhibited cytotoxicity against all tested cell lines with IC50 values ranging from 22.04 to 45.03 µM.


Assuntos
Antineoplásicos Fitogênicos/química , Pachyrhizus/química , Extratos Vegetais/química , Folhas de Planta/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chalconas/química , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/química , Glicosídeos/química , Humanos , Isoflavonas/química , Lactonas/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Vietnã
12.
Plant Foods Hum Nutr ; 76(2): 179-188, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33755896

RESUMO

Pachyrhizus ahipa is an unexploited crop known to be rich in proteins compared to other edible roots and tubers. These proteins are not prolamins, thus ahipa represents an interesting new source of ingredients for gluten-free foods. In this work, ahipa proteins (AP) were extracted and partially characterized in pursuit of their use as food ingredients. The effect of ultrasound treatment on protein extraction efficiency was evaluated. AP were characterized by their size, amino acid composition, surface hydrophobicity, intrinsic fluorescence, FTIR spectra, solubility, and thermal and emulsifying properties. AP were efficiently removed from the vegetal tissue using PBS or water, regardless of the use of ultrasound, but not easily recovered by precipitation. This protein fraction was composed of small proteins, with sizes ranging from 9 to 30 kDa, and highly polar. AP resulted particularly rich in aspartic acid (59% of the total amino acid content), for which they can be classified as Asp-rich proteins. Their elevated content of acidic groups was evidenced in the ATR-FTIR spectrum. The amide I band deconvolution as well as the low surface hydrophobicity and denaturation enthalpy indicated that these proteins are mainly unordered structures. The emulsifying properties of AP were enhanced when the concentration was increased from 0.1 to 1% (w/v) but resulted lower than those of soy protein. The high polarity, small size, and low isoelectric point make AP particularly suitable for acidic food matrices.


Assuntos
Pachyrhizus , Interações Hidrofóbicas e Hidrofílicas , Raízes de Plantas , Solubilidade , Água
13.
Carbohydr Polym ; 251: 117042, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142600

RESUMO

Production of inulin from yam bean tubers by ultrasonic assisted extraction (UAE) was optimized by using response surface methodology (RSM) and genetic algorithms (GA). Yield of inulin was obtained between 11.97%-12.15% for UAE and 11.21%-11.38% for microwave assisted extraction (MAE) using both the methodologies, significantly higher than conventional method (9.9 %) using optimized conditions. Under such optimized condition, SEM image of root tissues before and extraction showed disruption and microfractures over surface. UAE provided a shade better purity of extracted inulin than other two techniques. Degree of polymerization in inulin was also recorded to be better, might be due lesser degradation during extraction. Significant prebiotic activity was recorded while evaluation using Lactobacillus fermentum and it was 36 % more than glucose treatment. Energy density by UAE was few fold lesser than MAE. Carbon emission was far more less in both these methods than the conventional one.


Assuntos
Algoritmos , Fracionamento Químico/métodos , Inulina/isolamento & purificação , Inulina/farmacologia , Pachyrhizus/química , Raízes de Plantas/química , Prebióticos/análise , Fracionamento Químico/instrumentação , Inulina/química , Limosilactobacillus fermentum/efeitos dos fármacos , Micro-Ondas , Propriedades de Superfície , Ondas Ultrassônicas
14.
Environ Res ; 183: 109158, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32044575

RESUMO

Jicama peroxidase (JP) immobilized functionalized Buckypaper/Polyvinyl alcohol (BP/PVA) membrane was synthesized and evaluated as a promising nanobiocomposite membrane for methylene blue (MB) dye removal from aqueous solution. The effects of independent process variables, including pH, agitation speed, initial concentration of hydrogen peroxide (H2O2), and contact time on dye removal efficiency were investigated systematically. Both Response Surface Methodology (RSM) and Artificial Neural Network coupled with Particle Swarm Optimization (ANN-PSO) approaches were used for predicting the optimum process parameters to achieve maximum MB dye removal efficiency. The best optimal topology for PSO embedded ANN architecture was found to be 4-6-1. This optimized network provided higher R2 values for randomized training, testing and validation data sets, which are 0.944, 0.931 and 0.946 respectively, thus confirming the efficacy of the ANN-PSO model. Compared to RSM, results confirmed that the hybrid ANN-PSO shows superior modeling capability for prediction of MB dye removal. The maximum MB dye removal efficiency of 99.5% was achieved at pH-5.77, 179 rpm, ratio of H2O2/MB dye of 73.2:1, within 229 min. Thus, this work demonstrated that JP-immobilized BP/PVA membrane is a promising and feasible alternative for treating industrial effluent.


Assuntos
Azul de Metileno , Redes Neurais de Computação , Pachyrhizus , Poluentes Químicos da Água , Adsorção , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Peroxidase , Peroxidases , Álcool de Polivinil
15.
Am J Emerg Med ; 38(6): 1296.e1-1296.e3, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31956048

RESUMO

A 64-year-old woman presented with coma, seizure, and lactic acidosis after ingesting 80 yam bean seeds. This rotenone-containing seeds cause cellular asphyxia via blockage of the mitochondrial electron transport. Subsequent oxidative stress results in the formation of lipid peroxidation (LPO). Rotenone analysis via liquid chromatography mass spectrometry revealed the following: 31,590 ng/mL in cooked yam bean seed and 100 ng/mL in the blood. We attempted to use N-acetylcysteine to alleviate oxidative stress and documented the continuous decline in the plasma concentration of LPO.


Assuntos
Pachyrhizus/efeitos adversos , Rotenona/análise , Acidose Láctica/complicações , Acidose Láctica/etiologia , Coma/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Rotenona/efeitos adversos , Rotenona/sangue , Convulsões/etiologia
16.
Mar Drugs ; 17(12)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775217

RESUMO

Different composite films composed of tilapia skin collagen (TSC) with Pachyrhizus starch (PS) or rambutan peel phenolics (RPP) were prepared, and the physical properties of these films were determined. The effects of PS and RPP on TSC films were investigated, and our results indicated that PS and RPP could improve the physical properties of TSC films. Opacity and film thickness showed an enhanced trend with increasing PS and RPP contents in TSC films, whereas solubility in water, elongation-at-break (EAB), and water vapor permeability (WVP) showed declining trends. TSC film with 10% PS and 0.5% RPP had the highest tensile strength, and the tensile strength dropped drastically when the content of PS and RPP increased. The light transmittances of the films could decrease with the incorporation of PS and RPP. Differential scanning calorimetry (DSC) demonstrated that the addition of PS and RPP improved the thermal stability of TSC films. In addition, X-ray diffraction indicated that the crystallinity of the films decreased and the amorphous structure of the films tended to become more complex with the addition of PS and RPP. As shown by fourier transform infrared spectroscopy (FTIR) analysis, PS and RPP can strongly interact with TSC, resulting in a modification of its structure. Scanning electron microscope (SEM) analysis showed that there was a good compatibility between TSC, PS, and RPP. The results indicated that TSC film incorporated with 10% PS and 0.5% RPP was an effective method for improve the physical properties of the film. TSC-PS-RPP composite films can be used not only in biomedical applications, but also as active food packaging materials.


Assuntos
Colágeno/química , Pachyrhizus , Fenóis/química , Sapindaceae , Pele/química , Amido/química , Tilápia , Animais , Quitosana/química , Embalagem de Alimentos , Permeabilidade , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Difração de Raios X
17.
Carbohydr Polym ; 213: 199-207, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879661

RESUMO

This work discloses the multi-scale structure and pasting/digestion behaviors of yam bean tuber starches (YB-GD and YB-SC). Compared to potato starch, YB starches exhibited varied pasting/digestion features that were understood from a multi-scale structural view. Especially, YB starches showed relatively polydisperse lamellae, less perfect crystallites, and fewer amylose molecules. These features should reduce the bulk density of starch chain packing, and could facilitate the water or enzyme diffusion in starch matrixes. Consistently, not only was starch's resistance to hydrothermal effects weakened (shown by reduced pasting temperature), but also the enzyme absorption to starch chains and the subsequent hydrolysis events were accelerated. Furthermore, YB starch molecules had more short chains, which played roles in reducing the paste viscosity along with the reduced granule size and in enhancing the paste stabilities during heating and cooling. Also, those molecular features tended to speed up the enzyme diffusion and digestion events.


Assuntos
Pachyrhizus/metabolismo , Tubérculos/metabolismo , Amido/metabolismo , Configuração de Carboidratos , Pachyrhizus/química , Tamanho da Partícula , Tubérculos/química , Amido/química , Propriedades de Superfície
18.
Food Chem ; 283: 83-91, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722929

RESUMO

This work focused in the study of the changes on the physicochemical properties of isolated jícama starch (IJS), and IJS added with 0.15, 0.20, 0.30% Ca(OH)2 w/w. including: the structural, morphological, chemical, vibrational, pasting, rheological, and thermal characteristics. K, Ca, Na, and P were found in IJS. X-ray patterns, which showed that nanocrystals form the IJS according to the PDF-4 simulation. The functional properties were affected by the Ca inclusion, which originated electrostatic interactions. The gelatinization temperatures shifted to high values and exhibited an unfolding. The calculation of the IR absorption coefficient (ß) of the gelatinized samples as a function of the Ca2+ for the C-OH showed that the Van der Waals interaction causes the changes in the rheological-mechanical properties. The SEM images demonstrated that starch without alkali exhibited a porous network structure, while the starch with lime exhibited flakes and porous network. The gels of Jicama starch with Ca(OH)2 showed a viscoelastic behavior (G' > G″) with a reduction of their elastic module.


Assuntos
Hidróxido de Cálcio/química , Pachyrhizus/metabolismo , Amido/química , Amilose/metabolismo , Microscopia Eletrônica de Varredura , Nanopartículas/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Viscosidade , Difração de Raios X
19.
Food Res Int ; 116: 620-627, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716988

RESUMO

Cassava sour starch is a gluten-free product obtained by natural fermentation and sun-drying that outstrips the native starch baking expansion properties. Although maize starch has been subjected to a similar process, this desirable feature could not be achieved. Ahipa, an unexploited tuberous root, renders starch with relatively low gelatinization temperature and amylose content, like that of cassava. The aim of this work was to study the characteristics and technological properties of ahipa starch subjected to different fermentation processes and drying methods (oven- or sun-drying) and compare the bakery quality of its derived products to those from fermented cassava starches. Ahipa starch followed similar fermentation paths to those followed by cassava's, and sun-drying significantly reduced the content of the resultant lactic and butyric acids. Rheological behavior of starch pastes as well as moisture content and hardness of the doughs obtained from fermented and sun-dried ahipa starches differed from those of cassava. Sun-light exposure resulted detrimental for the expansion properties of ahipa sour starches, while the native one showed baking expansion properties like those of fermented sun-dried cassava starch. Thus, ahipa starch represents an interesting ingredient for the elaboration of gluten-free baked products.


Assuntos
Pão/análise , Dieta Livre de Glúten , Fermentação , Manihot/metabolismo , Pachyrhizus/metabolismo , Amido/metabolismo , Luz Solar , Pão/microbiologia , Culinária , Dessecação , Microbiologia de Alimentos , Dureza , Manihot/microbiologia , Pachyrhizus/microbiologia , Raízes de Plantas/metabolismo , Reologia , Viscosidade , Água/análise
20.
Int J Biol Macromol ; 116: 1214-1221, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29772335

RESUMO

This paper reported the results of the characterization of jicama (Pachyrhizus erosus) starch based biocomposite reinforced with varied nanofiber fractions, i.e. 35.4, 70.8 and 106.2 µg per 10 g of starch. The nanofiber was isolated from oil palm empty fruit bunches. During preparation, the biocomposite in form of gel was sonicated using an ultrasonic probe at various powers, i.e. 0, 480, 600, 720 watt at 20 kHz for 5 min. The results show that ultrasonication results in a significant improvement in biocomposite properties for each of the nanofiber fractions. The tensile strength, moisture resistance of the 35.4 µg nanofibers biocomposite increase significantly 278, 11% respectively after 600 watt ultrasonication. Field emission scanning electron microscopy of the fracture surface of the film showed ultrasonication resulted in it becoming smoother and more compact. These results indicate that ultrasonication improves the performance of the film.


Assuntos
Nanofibras/química , Pachyrhizus/química , Amido/química , Ondas Ultrassônicas
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