Oxidation of Polyphenols and the Effect on In vitro Iron Accessibility in a Model Food System

Composição química e antinutrientes presentes nas amêndoas cruas e torradas de chicha (Sterculia striata A. St. Hill & Naudin)

OBJETIVO: Analisar os componentes químicos e antinutrientes antes e após torrefação da amêndoa de chichá da espécie Sterculia striata A. St. Hill & Naudin, oriunda de Corrente, Piauí. MÉTODOS: Foram realizadas análises: centesimal, perfil de ácidos graxos, antinutrientes (taninos, inibidor de tripsina, inibidor de amilase, lectina, fitatos), compostos fenólicos e atividade de peroxidase e polifenoloxidase. RESULTADOS: Os resultados da análise centesimal da amêndoa crua e torrada foram: lipídeos de 25,1% e 26,2%, carboidratos de 44,4% e 45,6%, proteína de 20,8% e 22,1%, cinzas de 3,7% e 4,0%, fibra alimentar total de 12,3% e 10,4%, respectivamente. Nas amêndoas cruas e torradas não foram encontradas lectinas, taninos, inibidores de tripsina e alfa-amilase. Verificou-se a ausência de peroxidase e polifenoloxidase e conteúdo de compostos fenólicos de 107,7mg/100g e 108,9mg/100g para amêndoas cruas e torradas, respectivamente. CONCLUSÃO: A torrefação realizada a 205°C por 11 minutos diminuiu o teor de fitatos de 10,6mg/g para 5,5mg/g. Por fim, as amêndoas de chichá, cruas e torradas, apresentam alto teor de proteínas, fibras, ácidos graxos monoinsaturados e saturados.

Dietary polyphenols affect MUC5AC expression and ciliary movement in respiratory cells and nasal mucosa

BACKGROUND

Dietary polyphenols have been widely consumed in food, and their anti-inflammatory and anticancer activities have been recently studied. Although the effects of dietary polyphenols on mucin hypersecretion have been studied to some extent, the effects of mucociliary movement have not been elucidated thus far. Therefore, we investigated whether dietary polyphenols inhibit MUC5AC gene expression in NCI-H292 cells, and, if so, whether they would have an effect on ciliary beat frequency (CBF) of human nasal mucosa.

METHODS

NCI-H292 cells were pretreated with four different dietary polyphenols ([6]-gingerol, epigallocatechin gallate (EGCG), curcumin, and quercetin) and were treated with IL-1beta (10 ng/mL). Proliferation of NCI-H292 cells was analyzed. The mRNA expression of MUC5AC was determined by real-time polymerase chain reaction. CBF of normal nasal mucosa, which was obtained from the ethmoid sinus and treated with the polyphenols, was assessed via inverted microscope and computerized program.

RESULTS

Minimal inhibitory concentration (MIC) of MUC5AC expression of each polyphenol was found as follows: [6]-gingerol, 1 microM; EGCG, 20 microM; quercetin, 40 microM; and curcumin, 10 microM. No polyphenol influenced cell proliferation at this MIC. CBF was not affected by [6]-gingerol, quercetin, or EGCG, but ciliary movement decreased in curcumin.

CONCLUSION

[6]-Gingerol, quercetin, and EGCG may be considered as antihypersecretory agents because they effectively inhibit mucus secretion of respiratory epithelial cells while maintaining normal nasal ciliary movement.

Effects of phytase, cellulase, and dehulling treatments on iron and zinc in vitro solubility in faba bean (Vicia faba L.) Flour and Legume Fractions

Simulations of gastrointestinal digestion were used to try to identify the nature of the complexes between antinutritional factors and iron and zinc in faba bean and legume fractions. In digestible residue of raw faba bean flour, simultaneous action of cellulase and phytases made it possible to release about 28% units more iron than that released with the treatment without enzymes. About 49.8% of iron in raw faba bean flour was solubilized after in vitro digestion and simultaneous action of cellulase and phytase. In the hull fraction, the action of phytases and the simultaneous action of cellulase and phytase allowed about 7 and 35% units of additional zinc to be solubilized, respectively. Single enzymatic degradation of phytates from dehulled faba bean allowed solubilization from 65 to 93% of zinc, depending upon the treatment. In dehulled faba bean, iron was chelated by phytates and by fibers, whereas zinc was almost exclusively chelated by phytates. In the hull of faba bean, a high proportion of iron was chelated by iron-tannins, while the rest of iron as well as the majority of zinc were chelated in complexes between phytates and fibers.

Stability of Active Ingredients of Traditional Chinese Medicine (TCM)

Studies on stability of active ingredients are fundamental and critical for the rational development of Traditional Chinese Medicine (TCM) in view of its modernization and worldwide use. The stability of both active and marker constituents of plants used in TCM is reviewed for the first time. More than 100 papers, mostly written in Chinese, have been reviewed. Studies concerning plant constituents were analyzed according to their chemical classification of active ingredients. In addition, several crude drugs of animal origin are also reported. Stability of active ingredients is summarized during extraction and/or storage of the herbal drug preparations, and under stress conditions (pH, temperature, solvents, light, and humidity) and in the presence of preservatives, antioxidants, and metals.

Nutritional Value of Cassava for Use as a Staple Food and Recent Advances for Improvement

  Cassava is a drought-tolerant, staple food crop grown in tropical and subtropical areas where many people are afflicted with undernutrition, making it a potentially valuable food source for developing countries. Cassava roots are a good source of energy while the leaves provide protein, vitamins, and minerals. However, cassava roots and leaves are deficient in sulfur-containing amino acids (methionine and cysteine) and some nutrients are not optimally distributed within the plant. Cassava also contains antinutrients that can have either positive or adverse effects on health depending upon the amount ingested. Although some of these compounds act as antioxidants and anticarcinogens, they can interfere with nutrient absorption and utilization and may have toxic side effects. Efforts to add nutritional value to cassava (biofortification) by increasing the contents of protein, minerals, starch, and β-carotene are underway. The transfer of a 284 bp synthetic gene coding for a storage protein rich in essential amino acids and the crossbreeding of wild-type cassava varieties with Manihot dichotoma or Manihot oligantha have shown promising results regarding cassava protein content. Enhancing ADP glucose pyrophosphorylase activity in cassava roots or adding amylase to cassava gruels increases cassava energy density. Moreover, carotenoid-rich yellow and orange cassava may be a foodstuff for delivering provitamin A to vitamin A-depleted populations. Researchers are currently investigating the effects of cassava processing techniques on carotenoid stability and isomerization, as well as the vitamin A value of different varieties of cassava. Biofortified cassava could alleviate some aspects of food insecurity in developing countries if widely adopted.

Preventive effects of Spirulina platensis on skeletal muscle damage under exercise-induced oxidative stress

The effects of spirulina supplementation on preventing skeletal muscle damage on untrained human beings were examined. Sixteen students volunteered to take Spirulina platensis in addition to their normal diet for 3-weeks. Blood samples were taken after finishing the Bruce incremental treadmill exercise before and after treatment. The results showed that plasma concentrations of malondialdehyde (MDA) were significantly decreased after supplementation with spirulina (P < 0.05). The activity of blood superoxide dismutase (SOD) was significantly raised after supplementation with spirulina or soy protein (P < 0.05). Both of the blood glutathione peroxidaes (GPx) and lactate dehydrogenase (LDH) levels were significantly different between spirulina and soy protein supplementation by an ANCOVA analysis (P < 0.05). In addition, the lactate (LA) concentration was higher and the time to exhaustion (TE) was significantly extended in the spirulina trail (P < 0.05). These results suggest that ingestion of S. platensis showed preventive effect of the skeletal muscle damage and that probably led to postponement of the time of exhaustion during the all-out exercise.

Relative contribution of phytates, fibers, and tannins to low iron and zinc in vitro solubility in pearl millet (Pennisetum glaucum) flour and grain fractions

In vitro digestions were performed on pearl millet flours with decreased phytate contents and on two dephytinized or nondephytinized pearl millet grain fractions, a decorticated fraction, and a bran fraction with low and high fiber and tannin contents, respectively. Insoluble residues of these digestions were then incubated with buffer or enzymatic solutions (xylanases and/or phytases), and the quantities of indigestible iron and zinc released by these different treatments were determined. In decorticated pearl millet grain, iron was chelated by phytates and by insoluble fibers, whereas zinc was almost exclusively chelated by phytates. In the bran of pearl millet grain, a high proportion of iron was chelated by iron-binding phenolic compounds, while the rest of iron as well as the majority of zinc were chelated in complexes between phytates and fibers. The low effect of phytase action on iron and zinc solubility of bran of pearl millet grain shows that, in the case of high fiber and tannin contents, the chelating effect of these compounds was higher than that of phytates.