Folic acid encapsulation and evaluation of its stability against thermal treatments and UVA irradiation

Folic acid is a precursor micronutrient of several enzymatic cofactors required for nucleic acid synthesis, amino acid interconversion, DNA methylation, RNA and proteins. Poor folate feeding can lead to various disorders in humans, such as birth defects, heart disease, megaloblastic anemia, Alzheimer's disease, and some types of cancers. In view of the instability of folic acid under different conditions, the purpose of this study was to characterize the fibers and zein capsules prepared by the electrospinning and electrospraying techniques, respectively, and to use them to encapsulate folic acid. Solutions of zein 30% were used for fiber production and 9% for the development of capsules. Folic acid at concentrations of 0.5, 1.0 and 1.5% (w / v) in the polymer solutions was added. The fibers and capsules were evaluated for morphology, diameter, infrared spectroscopy with Fourier transform (FTIR), thermal properties by thermogravimetric analysis (TGA), encapsulation efficiency, thermal stability and light by liquid chromatography high efficiency coupled to mass spectrometry / MS). Solutions of pure zein and folic acid added were able to form uniform fibers and capsules. The mean diameter of the fibers varied from 369 to 702 nm, whereas the capsules were 291 to 339 nm. There was interaction between folic acid and zein observed by FTIR spectra, for both fibers and capsules. The encapsulation of folic acid in the form of fibers or capsules increased its thermal stability, as observed by thermogravimetric curves. Folic acid zein fibers and capsules showed high encapsulation efficiency (> 80%). Pure folic acid showed 70% degradation when exposed to 180 ° C, while fiber or capsule encapsulation provided the stability of folic acid. The photodegradation of pure folic acid was approximately 26%, however, when the vitamin was incorporated into the zein fibers, light stability was observed. The fibers and zein capsules with folic acid developed in this work, presented promising characteristics for application in foods that require thermal processing and exposure to light.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESO ácido fólico é um micronutriente precursor de vários cofatores enzimáticos necessários para a síntese de ácidos nucleicos, interconversão de aminoácidos, metilação do DNA, RNA e proteínas. Uma alimentação deficiente de folatos pode ocasionar vários distúrbios em humanos, tais como defeitos congênitos, doenças cardíovasculares, anemia megaloblástica, doença de Alzheimer e alguns tipos de câncer. Tendo em vista a instabilidade do ácido fólico a diferentes condições, objetivou-se com esse estudo caracterizar as fibras e cápsulas de zeína preparadas pelas técnicas de electrospinning e electrospraying, respectivamente e utilizá-las para encapsular o ácido fólico. Soluções de zeína 30% foram utilizadas para produção de fibras e 9% para o desenvolvimento de cápsulas. Foram adicionados ácido fólico nas concentrações de 0,5, 1,0 e 1,5% (p/v) nas soluções poliméricas. A fibras e cápsulas foram avaliadas quanto a morfologia, diâmetro, espectroscopia de infravermelho com transformada de fourier (FTIR), propriedades térmicas por análise termogravimétrica (TGA), eficiência de encapsulamento, estabilidade térmica e a luz por cromatografia líquida de alta eficiência acoplada a espectrômetro de massa (LC/MS). As soluções de zeína pura e adicionadas de ácido fólico foram capazes de formar fibras e cápsulas uniformes. O diâmetro médio das fibras variou de 369 a 702 nm, enquando das cápsulas foram de 291 a 339 nm. Houve interação entre o ácido fólico e a zeína observada pelos espectros de FTIR, tanto para fibras como para cápsulas. O encapsulamento do ácido fólico na forma de fibras ou cápsulas aumentou sua estabilidade térmica, conforme observado pelas curvas termogravimetricas. As fibras e as cápsulas de zeína com ácido fólico apresentaram alta eficiência de encapsulação (>80%). O ácido fólico puro apresentou 70% de degradação quando exposto a 180°C, enquanto o encapsulado em fibras ou em cápsulas proporcionou a estabilidade do ácido fólico. A fotodegração do ácido fólico puro foi de aproximandamente 26%, no entanto, quando a vitamina foi incorporada as fibras de zeína,foi observado estabilidade a luz. As fibras e cápsulas de zeína com ácido fólico desenvolvidas nesse trabalho, apresentaram características promissoras para aplicação em alimentos que necessitam de processamentos térmicos e exposição a luz

Antioxidant activity of black bean (Phaseolus vulgaris L.) protein hydrolysates

Abstract The objective of this work was to study the effect of enzymatic hydrolysis of black bean protein concentrate using different enzymes. Bean proteins were extracted and hydrolyzed over a period of 120 min using the enzymes pepsin or alcalase. The protein hydrolysates’ molecular weight was assayed by electrophoresis and the antioxidant activity was evaluated by the capturing methods of free radicals ABTS●+ and DPPH. Electrophoretic results showed that the bands above 50 kDa disappeared, when the beans protein was subjected to hydrolysis with pepsin. The bean protein hydrolysate obtained by hydrolysis with alcalase enzyme, showed higher antioxidant activity for inhibition of the radical ABTS●+. However, the hydrolysates obtained by hydrolysis with pepsin had higher antioxidant activity for inhibition of the radical DPPH. The use of pepsin and alcalase enzymes, under the same reaction time, produced black bean protein hydrolysates with different molecular weight profiles and superior antioxidant activity than the native bean protein

Antioxidant activity of black bean (Phaseolus vulgaris L.) protein hydrolysates

Abstract The objective of this work was to study the effect of enzymatic hydrolysis of black bean protein concentrate using different enzymes. Bean proteins were extracted and hydrolyzed over a period of 120 min using the enzymes pepsin or alcalase. The protein hydrolysates’ molecular weight was assayed by electrophoresis and the antioxidant activity was evaluated by the capturing methods of free radicals ABTS●+ and DPPH. Electrophoretic results showed that the bands above 50 kDa disappeared, when the beans protein was subjected to hydrolysis with pepsin. The bean protein hydrolysate obtained by hydrolysis with alcalase enzyme, showed higher antioxidant activity for inhibition of the radical ABTS●+. However, the hydrolysates obtained by hydrolysis with pepsin had higher antioxidant activity for inhibition of the radical DPPH. The use of pepsin and alcalase enzymes, under the same reaction time, produced black bean protein hydrolysates with different molecular weight profiles and superior antioxidant activity than the native bean protein