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The blue corn-based products are considered functional foods due to their high concentration of anthocyanins. The aim of this study was to estimate the kinetic and thermodynamic parameters of the thermal degradation of anthocyanins from extruded nixtamalized corn products. A comparative study of anthocyanins thermal stability in these matrices in a buffer solution (pH 2.5) was investigated at different temperatures (60, 75 or 90 °C). Results showed the mechanism of anthocyanins degradation followed first-order reaction kinetics. The values of the reaction rate constant (k) were found to be in a range of 0.027–0.037 h−1 at 60 °C, 0.107–0.113 h−1 at 75 °C and 0.340–0.354 h−1 at 90 °C. The higher the k value was, the shorter the half-life time and D-value. The activation energy (Ea) and z-values were in the range of 75.1–89.2 kJ/mol and 28.8–35.1 °C, respectively. The coefficient Q10 indicated the reaction rate approximately doubles with every 10 °C temperature increase. ∆H, ∆S and ∆G indicated the degradation of anthocyanins was an endothermic and nonspontaneous reaction. Even the major susceptibility of the anthocyanins in extruded nixtamalized corn products at the time–temperature combination applied, there was not difference between flour and tortilla, this imply that most of the anthocyanins were degraded during the nixtamalization extrusion process and no significative further degradation occur in the cooking step. This study provides and advance in the knowledge on the effect of nixtamalization extrusion process and tortillas making on the stability of anthocyanins from blue corn. However, further studies are needed.

In this investigation, the purified sulphoraphane from broccoli seed meal was evaluated in a range of 5–400 μg mL⁻¹ against Escherichia coli. The results showed that levels above 200 μg mL⁻¹ can inhibit 100% growth of 10⁶ CFU mL⁻¹ up to 5 h and cause a deformation of sigmoid behaviour in the growth kinetics, and even the bacterial population is reduced. On the other hand, low sulphoraphane levels such as 5–25 μg mL⁻¹ also have effects on the bacterium, such as the decrease in the maximum specific growth rate and the loss of ability to adjust to a growth model when maintained in isothermal conditions. In addition, sulphoraphane has an effect on swimming motility and swarming motility in semi‐solid medium. The interaction of natural sulphoraphane–E. coli and the effect in the short periods can draw attention in research on food science and technology.

Arginine, taurine, and choline are conditionally essential nutrients, and their dietary deficiency manifests as certain hepatic disorders. Arginine is an amino acid protein that aids in the detoxification and treatment of hepatic lesions. Taurine is a nonprotein amino acid that protects liver cells against oxidative stress and against various drugs. Choline is a water-soluble vitamin, and its deficiency is related to liver dysfunction. This review focuses on the scientific evidence that links arginine, taurine, and choline to the liver and liver diseases.

The aim of this study was to evaluate the effect of extrusion factors on the properties of extruded nixtamalized corn flours (ENCFs), determine the optimal conditions, and produce a tortilla with texture and nutraceutical characteristics acceptable for consumers. The processing factors used were feed moisture (FM, 15 to 30%), extruder temperature (T, 70 to 110 °C), and screw speed (SS, 50 to 145 rpm). The properties evaluated in the flours were total anthocyanins (TA), subjective water absorption capacity, and peak viscosity (PV). Response surface methodology and analysis of variance were used in the evaluation. The linear and quadratic terms of FM had a greater effect on all evaluated parameters. The optimization was performed using the numerical method of global desirability. The response variables that were optimized in the ENCF were TAs (maximize) and PV (maximize). The optimal region was the following: FM (18.17%), T (92.03 °C), and SS (76.61 rpm). The experimental value for the TA in the optimized ENCF was 226.07 mg/kg, and the PV was 1063.9 cP. The results of this study could help develop nixtamalized corn flours with desirable characteristics to make tortillas using the extrusion process. PRACTICAL APPLICATION: The results obtained would be useful for the tortilla industry, developing nixtamalized corn flours with desirable characteristics to make healthy tortillas using the extrusion process, with minimum losses in biologically active compounds such as anthocyanins (health promoters) without affect negatively the eating quality of the product (good texture).

Sulforaphane has received attention in recent years due to its biological properties; it is found in broccoli seeds but must be released by enzymatic action from its precursor molecule. In this study, a novel process to purification of sulforaphane from broccoli seeds is described. The procedure is divided in three consecutive steps: 1) hydrolysis and extraction, 2) adsorption/desorption of crude extract, and 3) bleaching step. The adsorption capacity (65–74 mg/g) and sulforaphane recovery (67–79%) were consistent in the adsorption/desorption step, which is important because it is possible to obtain up to 40% of sulforaphane content. Maximum bleaching was reached at 15–20 min, increasing the purity of sulforaphane considerably. It is possible to obtain 90% of bleaching and good recoveries. Purified sulforaphane from broccoli seed extracts was identified by mass spectrometry. Infrared and ultraviolet spectroscopy confirms the presence of sulforaphane in each step as well its separation and purification.

The objective of this study was to evaluate the in vitro effectiveness of membranes developed with pure chitosan and chitosan in a mixture with glycerol-honey against gram-negative bacteria isolated from skin ulcers. The membranes were prepared by the solvent evaporation technique. The identification and antibiotic sensitivity of microorganisms were determined in microplates, and in vitro tests were developed by the agar diffusion technique. The most frequently isolated microorganism was Escherichia coli with 43.75 % prevalence. All membranes showed antimicrobial effects by direct contact against Proteus mirabilis, Escherichia coli, Enterobacter aerogenes, Pseudomonas aeruginosa, Klebsiella pneumoniae and Morganella morganii. Antibiograms showed that most of these microorganisms are multi-resistant to antibiotics. All of this suggests that chitosan-based membranes are a safe alternative for the treatment of infected cutaneous ulcers compared to traditional antibiotics. The outcomes of this study confirm that membranes made of a biodegradable polymer, such as chitosan have activity against multidrug-resistant gram-negative bacteria that grow in infected skin ulcers.

Maillard reaction products (MRP) have gained increasing interest owing to their both positive and negative effects on human health. Aqueous amino acid-sugar model systems were studied in order to evaluate the antioxidant and chelating activity of MRP under conditions similar to those of food processing. Amino acids (cysteine, glycine, isoleucine and lysine) combined with different sugars (fructose or glucose) were heated to 100 and 130 °C for 30, 60 and 90 min. Antioxidant capacity was evaluated via ABTS and DPPH free radical scavenging assays, in addition to Fe2+ and Cu2+ ion chelating capacity.; Results: In the ABTS assay, the cysteine-fructose model system presented the highest antioxidant activity at 7.05 µmol mL-1 (130 °C, 60 min), expressed in Trolox equivalents. In the DPPH assay, the cysteine-glucose system presented the highest antioxidant activity at 3.79 µmol mL-1 (100 °C, 90 min). The maximum rate of chelation of Fe2+ and Cu2+ was 96.31 and 59.44% respectively in the lysine-fructose and cysteine-glucose systems (100 °C, 30 min).; Conclusion: The model systems presented antioxidant and chelating activity under the analyzed temperatures and heating times, which are similar to the processing conditions of some foods. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Sulforaphane is a phytochemical that has received attention in recent years due to its chemopreventive properties. However, the uses and applications of this compound are very limited, because is an unstable molecule that is degraded mainly by changes in temperature and pH. In this research, the use of food grade polymers for microencapsulation of sulforaphane was studied by a complex coacervation method using the interaction of oppositely charged polymers as gelatin/gum arabic and gelatin/pectin. The polymers used were previously characterized in moisture content, ash and nitrogen. The encapsulation yield was over 80%. The gelatin/pectin complex had highest encapsulation efficiency with 17.91%. The presence of sulforaphane in the complexes was confirmed by FTIR and UV/visible spectroscopy. The materials used in this work could be a new and attractive option for the protection of sulforaphane.

This study focuses on the isolation and quantification of astaxanthin and its esters in the oils extracted from shrimp waste. The content of astaxanthin was determined by high performance liquid chromatography and ranged from 1.5 to 2.1 mg g−1. The astaxanthin and its esters were isolated by thin layer chromatography in three fractions: free astaxanthin, monoester, and diester of astaxanthin, with percentages of 44, 32, and 26%, respectively. Oleic acid was the major fatty acid in the monoester fraction, while palmitic, oleic, and stearic acids were present predominantly in the diester fraction. Free radical-scavenging activity of the oils and the three fractions was evaluated. All oils showed an effect on the decrease in the absorbtion of 1,1-diphenyl-2-picrylhydrazyl solutions, while among the fractions no significant difference occurred. Pigmented oil from shrimp waste is an organic source of pigment and antioxidant astaxanthin, the esters, and fatty acids, such as eicosapentaenoic and docosahe...

Moringa oleifera tree has been recognized internationally for its nutritional, therapeutic and medicinal properties. Dry seeds are rich sources of oil with a high potential of commercial exploitation. The present study reports the physicochemical characterization, polyphenol content, DPPH radical scavenging capacity and fatty acid profile of moringa seed oil, and the chemical composition of the seed cultivated in Sonora, Mexico. Moisture, ash, protein and lipid contents in the seed were found to be 4.7, 5.8, 26 and 39%, respectively. The oil showed a refractive index of 1.4642. The saponification number was 183 mg KOH/g oil, iodine value: 75 g I/100 g of oil, acid value: 0.49 (% oleic acid). The polyphenol content was 0.137 mg of gallic acid equivalent/g and DPPH radical scavenging capacity was 87.39%. The moringa seed oil was rich (68%) in the major fatty acid, oleic acid (C18:1n9). Moringa oil extracted by sonication showed a fatty acid profile and physicochemical properties comparable to the oil from s...

Aloin is an anthraquinone-C-glycoside present in Aloe vera. This compound is extremely variable among different species and highly depends on the growing conditions of the plants. The quantification of aloin in different extraction preparations has been a frequent problem due to the high instability of the compound. The aim of the present study is to develop and validated an analytical method for aloin detection in fresh and dry samples of Aloe barbadensis gel and latex using high performance liquid chromatography coupled to a diode array detector (HPLC-DAD). Phosphate buffered saline (pH 3) was selected as the extraction solvent. The aloin was separated using a Zorbax Eclipse AAA column (4.6 × 150 mm) at 35°C, and water and acetonitrile were used as the mobile phase at a flow rate of 0.9 mL/min. The linearity was satisfactory with a correlation coefficient greater than 0.999. Under these conditions, the method precision (relative standard deviation) was 3.71% for FL, 4.41% for dry latex, 0.81% for fresh gel and 4.42% for dry gel samples. Aloe latex was determined to have a greater amount of aloin than aloe gel. The method validation was satisfactory and exhibited adequate linearity, repeatability and accuracy. This research was financed by project PROFAPI no. 2016-0025 from Instituto Tecnológico de Sonora. info:eu-repo/semantics/publishedVersion

Maillard reaction products (MRP) have gained increasing interest owing to their both positive and negative effects on human health. Aqueous amino acid-sugar model systems were studied in order to evaluate the antioxidant and chelating activity of MRP under conditions similar to those of food processing. Amino acids (cysteine, glycine, isoleucine and lysine) combined with different sugars (fructose or glucose) were heated to 100 and 130 °C for 30, 60 and 90 min. Antioxidant capacity was evaluated via ABTS and DPPH free radical scavenging assays, in addition to FeIn the ABTS assay, the cysteine-fructose model system presented the highest antioxidant activity at 7.05 µmol mLThe model systems presented antioxidant and chelating activity under the analyzed temperatures and heating times, which are similar to the processing conditions of some foods. © 2017 Society of Chemical Industry.

The objective of this research was to study the functional properties and proximate composition of three different flours prepared from cactus pear cladodes. Immature cactus pear cladodes were dried at 60 °C, 70 °C and 80 °C. The flours were analyzed for chemical composition, amino acid profile, fatty acid composition, functional properties and color. The analyses showed no significant differences in crude protein, total lipid, crude fiber and total ash content in the flours, possibly due to the drying temperature effect. Nevertheless, during the drying at 80 °C, a reduction of the water holding capacity (55%) was observed, along with a reduction of the green color intensity (34%) - characteristic of cactus pear. The heating produced larger concentrations of tyrosine, proline, aspartic acid, and glutamic acid. In the lipids of the flours, the most abundant fatty acids were palmitic acid (C16:0), linoleic acid (C18:2n6), linolenic acid (C18:3n3), and oleic acid (C18:1n9). The cladodes flours prepared at 60 °C presented a higher quality regarding their nutritional and functional properties. O objetivo desta pesquisa foi estudar as propriedades funcionais e a composição centesimal de três diferentes farinhas preparadas dos cladódios da palma forrageira. Palmas forrageiras não maturadas foram secadas a 60 °C, 70 °C e 80 °C, e as farinhas obtidas foram analisadas na sua composição química, no perfil dos aminoácidos, na composição de ácidos graxos, nas propriedades funcionais e na cor. Não houve diferenças significativas nos teores de proteína bruta, lipídios totais, fibra bruta e de cinzas totais nas farinhas pelo efeito da temperatura de secagem. No entanto, durante a secagem a 80 °C foi observada uma redução da capacidade de retenção de água (55%) e da intensidade da cor verde (34%), característica da palma forrageira. A tirosina, a prolina, o ácido aspártico e o ácido glutâmico foram encontrados em alta concentração. Nos lipídios das farinhas os ácidos graxos mais abundantes foram o ácido palmítico (C16: 0), o ácido linoleico (C18: 2n6), o ácido linolênico (C18: 3n3) e, o ácido oleico (C18:1n9). As farinhas dos cladódios da palma forrageira preparadas a 60 °C apresentaram uma alta qualidade em termos de suas propriedades nutricionais e funcionais.

Physicochemical changes of starch and loss of texture were determined in maize tortillas during 72 h storage at room and refrigeration temperatures. Properties analyzed included apparent amylose content, content of enzyme resistant starch (RS) type III, and thermal properties determined with differential scanning calorimetry (DSC) and X-rays diffraction. In addition, tortilla firmness was assessed using an uniaxial compression test with a texture analyzer. Storage temperature did not significantly affect firming rate or starch properties, except from thermal properties. Firmness was developed mainly during the first 24 h storage, remained nearly the same during 24—48 h and slightly increased after 72 h storage. Resistant starch (RS) formation followed the same trend as development of firmness. A first order endothermic transition that can be attributed to amylopectin retrogradation was observed after 2 h storage at both temperatures. This transition shifted to higher temperatures during storage, the effect was specially evident for refrigerated tortillas. X ray diffraction patterns of stored tortillas suggested that crystallinity slightly increased during storage. Most of the loss of tortilla texture, determined as firmness, occurred during the first 24 h storage at room and refrigeration storage conditions. This loss of texture was likely due to starch retrogradation and the latter possibly increased content of resistant starch.

Summary The proximate composition, amino acids content, fatty acid profile, total polyphenols, total flavonoids, DPPH radical scavenging capacity and sulforaphane content in broccoli seeds and sprouts were evaluated in this study. The results showed significant differences in the nutritional composition and the phytochemical level in the different stages of germination. Aspartic acid, glutamic acid, serine-histidine, proline and threonine were found in larger concentrations. Polyphenols and flavonoids content ranged from 9 to 77 mg GAE g−1 and 33 to 117 μg QE g−1, respectively. DPPH radical scavenging capacity ranged from 174 to 674 μmol TE g−1. The sulforaphane content in seeds and sprouts ranged from 273 to 3632 μg g−1–the highest values were found in seeds and the 8- and 11-day-old sprouts. The results suggest that the broccoli sprouts are a rich source of nutrients and phytochemicals, these have a high potential as functional food.

Biogenic amines in high concentration can affect the quality of foods and cause several diseases since they are present in products like seafood, wines, and other fermented products. Shrimp by-products are a rich source of protein hydrolysate that can be used as dietary supplements. Samples (from shrimp by-products) of dry protein powder, liquid protein hydrolysate and flour of shrimp head were analyzed to evaluate the histamine and tyramine contents. Amines were extracted with trichloroacetic acid 5% and derivatized with o-phthaldialdehyde. The chromatographic separation was performed in an analytical column, Chrom SEP SS C18 5 µm (4.6 mm × 150 mm) and a fluorescence detector was used with wavelengths at λex = 335 nm and λem = 440 nm. The mobile phase was a mixture of tetrahydrofuran, methanol and phosphate buffer at a flow rate of 0.6 mL min-1 using elution gradient. Under these conditions, the repeatability (relative standard deviation, RSD < 6.55%), reproducibility (< 5.60%) and accuracy were of satisfying quality. The recovery values were 84.51, 90.75, 95.37, 98.68 and 84.29% for L-tyrosine, L-tryptophan, L-lysine, tyramine and histamine, respectively. This method has been successfully applied for the quantification of precursor amino acids and biogenic amines in different matrices. Aminas biogênicas em alta concentração podem afetar a qualidade dos alimentos e causar várias doenças, pois estão presentes em produtos como frutos do mar, vinhos e outros produtos fermentados. Subprodutos do camarão são uma fonte rica de proteína hidrolisada que podem ser usadas como suplemento alimentar. Amostras (de subprodutos de camarão) de proteína seca em pó, proteínas hidrolisadas líquidas e farinha da cabeça de camarão foram analisadas para avaliar o conteúdo de histamina e tiramina. As aminas foram extraídas com ácido tricloroacético 5% e posteriormente derivatizadas com o-ftaldialdeído. A separação cromatográfica foi realizada em uma coluna analítica, Chrom SEP C18 SS 5 mm (4,6 mm × 150 mm) com eluição por gradiente, os comprimentos de onda foram λex = 335 nm e λem = 440 nm. A fase móvel utilizada foi uma mistura de tetrahidrofurano, metanol e tampão fosfato a uma vazão de 0,6 mL min-1. Sob essas condições, a repetibilidade (desvio padrão relativo < 6,55%), reprodutibilidade (< 5,60%) e exatidão foram satisfatórias. Os valores de recuperação foram 84,51, 90,75, 95,37, 98,68 e 84,29% para L-tirosina, L-triptofano, L-lisina, tiramina e histamina, respectivamente. Este método tem sido aplicado com sucesso para a quantificação de aminoácidos precursores e aminas biogênicas em matrizes diversas.

Sulforaphane (1-isothiocyanato-4-(methylsulfinyl)-butane) content in cruciferous vegetables. Sulforaphane is an isothiocyanate which has antimicrobial and anticarcinogenic properties, this compound is found in a wide variety of plants from genus Brassica oleracea, being the most important broccoli and cabbage. The objective of this research was to quantify sulforaphane in the edible parts of broccoli and cabbage leaves by high-performance liquid chromatography (HPLC). Sample preparation for the quantification of sulforaphane include the conversion of glucoraphanin to sulforaphane (45 +/- 2 degrees C for 2.5 h), extracted with dichloromethane, purification of the extract in columns of solid phase extraction and detection by HPLC- UV. Sulforaphane concentration in broccoli is in the range of 214 microg/g DW (stems) to 499 microg/g DW (inflorescences). The purple cabbage (101.99 microg/g DW) has values greater than the green cabbage (7.58 microg/g DW). The inflorescences of broccoli and red cabbage leaves are rich in sulforaphane.

La riboflavina (B2) es una vitamina hidrosoluble del complejo B, cuyo aporte nutritional es imprescindible para el buen funcionamiento del organismo. La leche es una de las principales fuentes de riboflavina en la dieta humana, sin embargo, en la mayoría de los alimentos se degrada durante los procesos térmicos convencionales y en el almacenamiento. En el presente trabajo se determinó el contenido de riboflavina en productos lácteos comerciales, leches para consumo directo y yogurt, por cromatografía líquida de alta resolución (HPLC) con detección por fluorescencia. La preparación de la muestra incluye una hidrólisis acida (HC10. IN), seguida por una digestión enzimática, y por último, la precipitación de proteínas (TCA100 %). En el análisis cromatográfico se utilizó un sistema isocrático (acetato de amonio 5 mM-metanol, 72:28 v/v). El contenido de riboflavina de las muestras de yogurt estuvo en el rango de 0,289 - 3,078 µ/g BS, mientras que en la leche ultrapasteurizada y pasteurizada de 0,61-13,64 µg/gBS y 11,73-15,41 µg/ g BS, respectivamente. Las leches para consumo directo y el yogurt comercial son fuentes de riboflavina, y su consumo regular puede ayudar a satisfacer los requerimientos diarios.

The objective of this research was to study the biochemical composition and physicochemical properties of three different flours prepared from broccoli crop remains. Florets, leaves and stalks of broccoli were dried at 60 degrees C, and the flours obtained were analysed for proximate composition, amino acid profile, fatty acid composition, and physicochemical properties. The florets flour showed the highest protein content (22.41 g/100 g dry weight); ash was higher in leaves flour (14.67 g/100 g dry weight), and the lipid content was similar in the flours of leaves and stalks. The stalks flour had high crude fibre content and low protein content. All flours presented a high water absorption index. Tyrosine, aspartic acid, glutamic acid, proline and valine were found in larger concentration. The most abundant fatty acids in the lipids were linolenic acid (C18:3n3), palmitic acid (C16:0) and linoleic acid (C18:2n6). Broccoli flours prepared in this study are good source of nutrients and could be utilized as dietary supplements.

A simple and specific analytical method was developed and tested for the determination of sulforaphane in broccoli by-products. The method includes the optimization of the conversion of glucoraphanin to sulforaphane, followed by purification of extracts using solid-phase extraction and high-performance liquid chromatography (HPLC) analysis. The response surface methodology was used to find optimum conditions for the preparation and purification procedure. Chromatographic conditions for reversed-phase HPLC with UV photodiode array detection were as follows: column, Exil ODS C(18), 25 x 0.46 cm, 5 microm; column temperature, 36 degrees C; mobile phase, a 30 : 70 (v/v) mixture of acetonitrile:water; flow rate, 0.6 mL/min. The detection wavelength was UV 202 nm. Under these conditions, excellent linearity was obtained (r(2) = 1), and the overall recovery was 97.5 and 98.1% for fresh florets and lyophilized florets, respectively. The precision results showed that the relative standard deviation of the repeatability for florets fresh and lyophilized was 3.0 and 4.0%, respectively. Sulforaphane contents were determined in the edible portion of fresh broccoli, and broccoli crop remains.