Decoding the Duality of Antinutrients: Assessing the Impact of Protein Extraction Methods on Plant-Based Protein Sources.

This review aims to provide an updated overview of the effects of protein extraction/recovery on antinutritional factors (ANFs) in plant protein ingredients, such as protein-rich fractions, protein concentrates, and isolates. ANFs mainly include lectins, trypsin inhibitors, phytic acid, phenolic compounds, oxalates, saponins, tannins, and cyanogenic glycosides. The current technologies used to recover proteins (e.g., wet extraction, dry fractionation) and novel technologies (e.g., membrane processing) are included in this review. The mechanisms involved during protein extraction/recovery that may enhance or decrease the ANF content in plant protein ingredients are discussed. However, studies on the effects of protein extraction/recovery on specific ANFs are still scarce, especially for novel technologies such as ultrasound- and microwave-assisted extraction and membrane processing. Although the negative effects of ANFs on protein digestibility and the overall absorption of plant proteins and other nutrients are a health concern, it is also important to highlight the potential positive effects of ANFs. This is particularly relevant given the rise of novel protein ingredients in the market and the potential presence or absence of these factors and their effects on consumers' health.

Screening of α-amylase/trypsin inhibitor activity in wheat, spelt and einkorn by high-performance thin-layer chromatography.

α-Amylase/trypsin inhibitor proteins (ATI) are discussed as possible triggers for non-celiac gluten sensitivity. The potential of high-performance thin-layer chromatography (HPTLC) was studied for the first time to analyse the inhibitory properties of ATIs from flour of wheat, spelt, and einkorn. Inhibition by each flour of the digestive enzymes trypsin or α-amylase was determined by the reduction of released metabolisation products in comparison to non-digested flour, and positive (acarbose) and negative (water) controls. Firstly, amylolysis was carried out in miniaturized form on the HPTLC surface (HPTLC-nanoGIT) after in-vial pre-incubation of the amylase with the inhibitors from flour. α-Amylase inhibition was evident via the reduction of released saccharides, as analysed by normal phase HPTLC. A strong influence of the flour matrix on the assay results (individual saccharides) was evident, caused by an increased amylolysis of further polysaccharides present, making HPTLC analysis more reliable than currently used spectrophotometric sum value assays. The detection and visualization of such matrix influence helps to understand the problems associated with spectrophotometric assays. Only maltotriose was identified as a reliable marker of the amylolysis. The highest α-amylase inhibition and thus the lowest saccharide response was detected for maltotriose in refined spelt, whereas the lowest α-amylase inhibition and thus the highest saccharide response was detected for maltotriose in refined wheat. A comparison of refined and whole grain flours showed no clear trend in the responses. Secondly, trypsin inhibition and proteolysis were performed in-vial, and any inhibition was evident via the reduction of released peptides, analysed by reversed-phase HPTLC. Based on the product pattern of the proteolysis, einkorn and whole wheat showed the highest trypsin inhibition, whereas refined wheat and refined spelt showed the lowest inhibition. Advantageously, HPTLC analysis provided important information on changes in individual saccharides or peptides, which was more reliable and sustainable than spectrophotometric in-vial assays (only sum value) or liquid column chromatography analysis (targeting only the ATI proteins).

Enzymatic and Algebraic Methodology to Determine the Contents of Kunitz and Bowman-Birk Inhibitors and Their Contributions to Total Trypsin or Chymotrypsin Inhibition in Soybeans.

Soybeans are the number one source of plant proteins for food and feed, but the natural presence of protein protease inhibitors (PIs), namely, the Kunitz trypsin inhibitor (KTI) and the Bowman-Birk inhibitor (BBI), exerts antinutritional effects. This communication describes a new methodology for simultaneously quantitating all parameters of PIs in soybeans. It consists of seven steps and featured enzymatically measuring trypsin and chymotrypsin inhibitory activities, respectively, and subsequently determining the contents of reactive KTI and BBI and the contributions of each toward total PI mass and total trypsin or chymotrypsin inhibition by solving a proposed system of linear equations with two variables (C = dB + eK and T = xB + yK). This enzymatic and algebraic (EA) methodology was based on differential inhibitions of KTI and BBI toward trypsin and chymotrypsin and validated by applications to a series of mixtures of purified KTI and BBI, two KTI-null and two conventional soybeans, and by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The EA methodology allowed calculations of PI composition and the contributions of individual inhibitors toward total inhibition with ease. It was first found that although BBI constituted only about 30% of the total PI mass in conventional raw soybeans, it contributed about 80% toward total chymotrypsin inhibitor activity and about 45% toward trypsin inhibitor activity. Therefore, BBI caused more total protease inhibitions than those of KTI. Furthermore, the so-called KTI-null soybean mutants still contained measurable KTI content and thus should be named KTI-low soybeans.

Unsaponifiable Compounds and Phenols Content, Antioxidant and Antitrypsin Activities of Prunus persica Kernel Oil.

Although peach kernels are rich in oil, there is a lack of information about its chemical and biological properties. Therefore, the purpose of this study was to determine the lipid profile, antioxidant capacity, and trypsin inhibitory propriety of peach oil extracted from two varieties (sweet cap and O'Henry) cultivated in Tunisia. The investigated peach kernel oil contains significant amount of unsaponifiable (2.1±0.5-2.8±0.2% of oil) and phenolic compounds (45.8±0.92-74.6±1.3 mg GAE/g of oil). Its n-alkane profile was characterized by the predominance of tetracosane n-C24 (47.24%) followed by tricosane n-C23 (34.43%). An important total tocopherol content (1192.83±3.1 mg/kg oil) has been found in sweet cap cultivar. Although rich in polyphenols and tocopherols, the tested oil did not display an inhibitory effect on trypsin. However, all peach oil samples showed effective antioxidant capacity and the highest values (86.34±1.3% and 603.50±2.6 µmol TE/g oil for DPPH test and ORAC assay, respectively) were observed for sweet cap oil. Peach oil has an excellent potential for application in the food and pharmaceutical industries as source of naturally-occurring bioactive substances.

Effect of different physical pre-treatments on physicochemical and techno-functional properties, and on the antinutritional factors of lentils (Lens culinaris spp).

Lentils have a valuable physicochemical profile, which can be affected by the presence of antinutrients that may impair the benefits arising from their consumption. Different treatments can be used to reduce these undesirable compounds, although they can also affect the general composition and behaviour of the lentils. Thus, the effect of different processing methods on the physicochemical and techno-functional properties, as well as on the antinutritional factors of different lentil varieties was studied. Phytic acid was eliminated during germination, while tannins and trypsin inhibitors are mostly affected by cooking. Functional properties were also altered by processing, these being dependent on the concentration of different nutrients in lentils. All the studied treatments affected the physicochemical profile of lentils and their functional properties. Cooking and germination appear to be the most effective in reducing antinutritional factors and improving the physicochemical profile of the lentils, meeting the current nutritional demands of today's society.

An infrared spectroscopic study on the secondary structure of the black-eyed pea trypsin and chymotrypsin inhibitor - amide I-III and V bands

The infrared spectrum of native black-eyed pea trypsin and chymotrypsin inhibitor (BTCI) in solid film was measured from 550 to 1750 cm-1 and amide I-III, and V regions have been analyzed. By comparison between the observed bands with the modes calculated for several structures (available inthe literature), the occurrence in BTCI of unordered, antipatallel ß-sheet, and ß-turn structures is suggested

The complete amino acids sequence of the Vigna unguiculata (L.) Walp. seed trypsin and chymotrypsin inhibitor

Foi determinado em nosso Laboratório a seqüência completa de aminoácidos de um inhbidor de tripsina e quimotripsina, "double-headed", denominado abreviadamente BTCI, purificado de feijäo caupi Vigna unguiculata (L.) Walp.cv."Seridó". Os peptídeos trípticos e quimiotrípticos foram seqüenciados pelos métodos manuais de Edman-Gray, de Edman-Chang (N-terminais) e de carboxypeptidases (C-terminais). É a seguinte a seqüência de aminoácidos do BTCI: Ser Gly-His-Glx-Asx-Ser-Thr-Asx-Glx-Ala-Ser-Glx-Ser-Ser-Lys-Pro-Cys-Cys-Arg-Glx-Cys-Ala-Cys-Thr-Lys-Ser-Ile-Pro-Pro-Glx-Cys-Arg-Cys-Ser-Asx-Val-Arg-Leu-Asn-Ser Cys-His-Ser-Ala-Cys-Lys-Ser-Cys-Thr=Phe-Ser-Ile-Pro-Ala-Glx-Xys-Phe-Cys-Gly=Asx-Ile-Asx-Asx-Phe-Cys=Tyr-Lys-Pro-Cys-Lys-Ser-Ser-His-Ser-Asx-Asx-Asx-Asx0Trp-Asn. BTCI apresenta alto grau de homologia como vários outros inibidores da família Bowman-Birk

Estudio sobre la composición quimica y contenido de factores antifisiologicos de la pasta residual de jojoba (Simmondsia chinensis) / Chemical composition and content of antiplysiological factors of jojoba (Simmondsia chinensis) residual meal

La jojoba (Simmondsia chinensis) es una planta que últimamente ha despertado grand interés mundial debido a la cera líquida que de ella se obtiene. Aun cuando se ha prestado mucha atención al uso potencial de esta cera como sustituto del aceite de ballena (cachalote), poco ha sido el trabajo efectuado sobre el subproducto, de elevado contenido proteínico, que queda después de la extracción del aceite. Considerando que una de las principales preocupaciones actuales es la búsqueda de nuevas fuentes de alimentos, tanto para consumo humano como animal, es clara la necesidad de efectuar un estudio sobre este producto. Como resultados significativos de la caracterización realizada se obtuvo: proteína cruda, 14.03 y 25.25%; extracto etéreo, 48.89 y 14.73%; fibra cruda, 10.03 y 10.07%; cenizas, 1.59 y 4.72, y extracto libre de nitrógeno, 25.46 y 45.25, siendo los aminoácidos limitantes la metionina, lisina e isoleucina; el inhibidor de tripsina, 13,747 y 11,197 UIT/g, y presencia de glucósidos cianogénicos en la semilla y la pasta, respectivamente. Se puede considerar, que por su valor nutritivo, la pasta residual de jojoba es un suplemento adecuado para la alimentación animal. Sin embargo, requiere de un tratamiento previo a su consumo para eliminar los factores tóxicos

Efeito da maltagem e da extrusäo termoplástica sobre a qualidade tecnológica da cultivar de soja Br 16 / Effect of malting and thermoplastic extrusion on the technologic quality of the derived product of soybean

Sementes de soja cultivar BR 16 foram submetidas à maltagem por 24 e 48 horas e à extrusao obtendo-se flocos, os quais foram moídos e utilizados na fabricaçao de biscoitos. Flocos e biscoitos foram analisados sensorialmente. O efeito da maltagem e da extrusao foram também avaliados em relaçao às características químico-nutricionais. A composiçao em macro nutrientes nao apresentou alteraçoes acentuadas mostrando pequeno decréscimo nos teores de carboidratos totais e discreto aumento relativo nos teores de carboidratos totais e discreto aumento relativo nos teores de lipídeos no produto maltado. Dentre os fatores antinutricionais, os inibidores de tripsina apresentaram queda de 50 por cento após 24h de maltagem e desaparecimento após a extrusao. Os teores de ácido fítico nao sofreram variaçao expressiva, enquanto que os alfa-galactosídeos apresentaram decréscimo de até 80 por cento com os processos combinados de maltagem e extrusao.

Precocción de harine de soya maíz por microonda, y su uso en la preparación de arepas / Precooked of soy flour and corn by the microwave and its use in the preparation of arepas

Se utilizó sémola de maíz y soya descascarada, con una granulometría entre 10 y 20 mesh (ASTM). El proceso de calentamiento por microonda es efectivo para destruir los factoes antinutricionales de la soya. La actividad inhibidora de la tripsina se redujo en un 76%. El título hemaglutinante resultó ser termolábil, obteniéndose valores de +8 a +3 para la soya integral y precocida, respectivamente. La calidad de la proteína medida por el índice de eficiencia proteínica (PER) dio valores de 2.63 para la harina de soya precocida, y de 2.46 y 2.21 para las mexclas maíz: soya (70:30 y 50:50). Estas mezclas crudas tenían valores de 1.17 y 1.04 respectivamente. La harina de maíz enriquecida con 10% de soya precocida presentó un valor de PER de 1.60; con soya precocida los valores de PER no difirieron (P < ou = 0.05) de los valores de PER de la caseína. La soya y mezclas maíz : soya acusaron una lata digestibilidad que no difiere significativamente (P < ou = 0.05) en relación a los índices de absorción de agua, solubilidad en agua, pegajosidad, separación de agua y expansibilidad de la harina y las diferentes mezxlas. Los resultados revelaron que el proceso de calentamiento en microondas mejora notablemente las propiedades funcionales y nutricionales de la harina enriquecida y de las arepas elaboradas con ésta

Valor nutricional y contenido de factores antinutricionales de harinas precocidas de granos de Canavalia ensiformis / Nutritional value and antinutritional factors content of precooked flours prepared from Canavalia ensiformis

Precooked flours obtained five Canavalia ensiformis varieties were prepared by dehydration in double drums. On a dry matter basis, significant differences (P < 0.05) among varieties were detected for crude protein content (25 to 30 percent), starch (36 to 40 percent) and dietary fiber (13 to 15 percent). Hemagglutinins were eliminated as result of the high temperature (146 degrees C/4 min) employed during the drying process. Similar results were not obtained for trypsin inhibitors and canavanine considering that small amounts of these compounds remained in the precooked flours prepared from canavalia seeds. A 10 percent decrease in available lysine was observed. Biological assays yielded Protein Efficiency Ratio (PER) values of 0, 8-1 and Neat Proteic Relation (NPR) values of 2-3-2.6. True digestibility of protein values were improved from 87 to 90 percent. All cultivars had similar starch digestive utilization coefficient (96 percent) and starch fraction (4 percent) resistant to enzymatic hydrolysis in the rat digestive tract

Efectos de la coccion tradicional sobre los factores antinutricionales de los frijoles negros (Phaseolus vulgaris) de Costa Rica / Effects of the traditional cooking on antinutritional factors of the black beans (Phaseolus vulgaris) of Costa Rica

En esta investigación se determinó la presencia de los inhibidores de tripsina, inhibidores de alfa amilase y hemaglutininas en los frijoles (P. vulgares) producidos en Costa Rica. Además, se estudió su comportamiento ante la cocción tradicional. Los factores antinutricionales se determinaron por espectofotometría en los frijoles crudos, y después de diferentes tiempos de cocción. Se observó que los inhibidores de alfa amilase son los más termorresistentes, ya que a los 30 min de cocción existe un 33% de la actividad inicial presente en el frijol crudo. Alrededor del 80% de la actividad antitripsina ha desaparecido de los 9 min de cocción. En cuanto a las hemaglutininas, a los 10 min la actividad es aproximadamente sólo de 1%

Effects of cone opening, initial moisture content and multiple extrusion on the protein quality of extruded soybean using the brady crop cooker

En el estudio aquí descrito se evaluaron los efectos de tres aberturas de cono (0.133, 0.106 y 0.080 cm) y tres contenidos iniciales de humedad (9,15 y 21%) en grano de soya procesado con el extrusor Brady, en la calidad proteínica del producto. El volumen específico, contenido de proteína, aceite y lisina disponible del producto final no fueron afectados por los tratamientos utilizados. Las temperaturas de procesamiento, sin embargo, disminuyeron al aumentarse el contenido inicial de humedad. El índice de solubilidad de nitrógeno se vio afectado por la abertura del cono, pero no por el contenido de humedad de la materia prima. No obstante, las temperaturas de procesamientos descendieron al aumentar el contenido inicial de humedad. Los resultados en cuanto al contenido de inhibidores de tripsina y ureasa, sin embargo, fueron conflictivos en relación al contenido inicial de humedad del grano. Así, cuando la humedad inicial era de 21%, la actividad de los inhibidores de tripsina fue superior a la materia prima, a 9% de humedad. Se detectó un efecto similar en lo referente a la actividad de la ureasa. Los niveles de estos factores antifisiológicos fueron menores en las muestras que contenían 9 y 15% de humedad inicial, respectivamente, debido al proceso térmico, principlamente al nivel de 1% de humedad, que estaban relacionados con la abertura de cono. Los valores de PER, en ratas, fueron influenciados por el contenido de humedada inicial, y no fueron por la abertura de cono. La reducción de esta última favoreció el aumento ponderal y la conversión alimenticia de los pollos, utilizados en las pruebas biológicas para evaluar la calidad nutricional del producto. El aumento en el contenido inicial de humedad, sin embargo, redujo el incremento en peso a las 5 y 8 semanas de estudio, sin afectar por ello la eficiencia de conversión del alimento. Se evaluó también el efecto de la extrusión del grano de soya, tres veces consecutivas, en la calidad nutricional. El producto extruido dos veces acusó un buen valor biológico, probablemente como consecuencia de los bajos valores de actividad de los inhibidores de tripsina y de ureasa. El producto extruido tres veces rindió resultados pobres, debido a la reducción a valores significativamente bajos del contenido de la lisina disponible - que se convierte en limitante- y nivel de índice de solubilidad del nitrógeno de la harina de soya integral