J.A. Gallegos-Infante

Influence of extrusion on the bioactive compounds and the antioxidant capacity of the bean/corn mixtures

The aim of this investigation was to examine the influence of extrusion on the bioactive compounds and the antioxidant capacity of bean/corn mixtures. Whole bean flour and nixtamalized corn were mixed in a 60:40 proportion and extrusion was performed in different moisture (14.5%, 15.4%, 17.1% and 18.0%) and temperature (150°C, 160°C, 170°C, 180°C and 190°C) conditions in order to find the optimal extrusion conditions. According to their functional properties and antioxidant status, the mixtures 142°C/16.3% H, 170°C/16.3% H and 198°C/16.3% H were defined as optimal, moderate and bad, respectively. Total polyphenols and flavonoids in the mixture of 142°C/16.3% H (15.09±1.7 mg gallic acid equivalent [GAE]/g dry weight [DW] and 1.57±0.2 mg catechin equivalent [CE]/g DW) were significantly higher (P<0.05) than in the sample 170°C/16.3% H (9.42±1.1 mg GAE/g DW and 1.4±0.1 mg CE/g DW) and the mixture 198°C/16.3% H (6.46±0.8 mg GAE/g DW and 0.78±0.1 mg CE/g DW). The antioxidant activity (37.02±3.8 and 25.01±2.5 µM Trolox equivalent [TE]/g DW) of mixture 142°C/16.3% H, determined by the cupric reducing antioxidant capacity with Trolox equivalent antioxidant capacity and β-carotene–linoleic acid (β-carotene,% of inhibition) assays, was significantly higher (P<0.05) than in 170°C/16.3% H (25.69±2.8 and 17.02±1.8 µM TE/g DW) and in mixture 198°C/16.3% H (13.93±1.5 and 8.94±0.9 µM TE/g DW), respectively. The free polyphenols, flavonoids and the antioxidant activities showed lower results than the hydrolyzed ones. The correlation coefficients between polyphenols, flavonoids, and cupric reducing antioxidant capacity capacities were between 0.93 and 0.99. In cereal proteins extracted and separated by electrophoresis, some differences were found in the sodium dodecyl sulfate–protein bands in the region from 36 to 45 kDa for 142°C/16.3% H, in comparison with other samples. Therefore, there is a need to find such conditions for the extrusion procedures that would take into consideration the contents of the bioactive compounds and the antioxidant capacity in the end product.

Effect of air flow rate on the polyphenols content and antioxidant capacity of convective dried cactus pear cladodes (Opuntia ficus indica)

The interest in nopal has encouraged the use of dehydration; there are few studies about the effect of process parameters on the nopal polyphenol content and antioxidant activity. The objective of the present work was to evaluate the effect of air-drying flow rates on the amount and antioxidant capacity of extracts of Opuntia ficus indica cladodes. Nopal was dried at 45°C and air flow rates of 3 and 5 m/sec. Samples were analyzed for moisture, total polyphenol, flavonoid, and flavonol contents, chain-breaking activity, inhibition of low-density lipoprotein and deoxyribose oxidation. Nopal drying at an air flow rate of 3 m/sec showed higher values of phenols, flavonoids and flavonols. The best value of low-density lipoprotein inhibition and deoxyribose was found at 1,000 µg/ml. The air flow rate affected the amount of polyphenols and the OH· radical scavenging, but did not modify the chain-breaking activity and the low-density lipoprotein inhibition activity.

Effect of the Addition of Common Bean (Phaseolus vulgaris L.) Flour on the In Vitro Digestibility of Starch and Undigestible Carbohydrates in Spaghetti

Spaghetti is considered to be a slowly digestible starch food, a feature ruled by the particular physical properties of the product. Several studies have been reported to increase nutritional value of spaghetti, using legumes. We have studied the addition of common bean flour on the starch in vitro digestibility. Spaghetti was prepared with semolina and different concentrations of common bean flour (0%, 15%, 30%, and 45%, w/w). Proximate analysis, optimal cooking time, and cooking loss were estimated in crude spaghetti. Total, available, and resistant starches, indigestible fractions, and in vitro starch hydrolysis kinetics were accomplished in cooked spaghetti. Pasta with 30% and 45% of common bean flour showed higher values of protein. Particularly, the lowest cooking time was observed for composite spaghetti with 45% of common bean flour. There was a significant increase in cooking loss when common bean flour in the composite was added. Composite spaghetti samples with increasing common bean flour showed decreasing values of total starch but an important increase in the resistant starch (RS) level and indigestible insoluble fraction values. Plain pasta made with semolina showed the highest enzymatic hydrolysis rate, which decreased when common bean flour was added to the spaghetti. Spaghetti with a higher level of common bean flour was more slowly available, which may have positive implications for human health.

Gastroprotective potential of Buddleja scordioides Kunth Scrophulariaceae infusions; effects into the modulation of antioxidant enzymes and inflammation markers in an in vivo model.

ETHNOPHARMACOLOGICAL RELEVANCE A common plant used to treat several gastric disorders is Buddleja scordioides Kunth, commonly known as salvilla. AIM OF THE STUDY To detect inflammatory markers, in order to evaluate the gastroprotective potential of salvilla infusions, as this could have beneficial impact on the population exposed to gastric ulcers and colitis. MATERIALS AND METHODS The present work attempted infusions were prepared with B. scordioides (1% w/w) lyophilized and stored. Total phenolic content and GC-MS analysis were performed. Wistar rats were divided into five groups (n=8), a negative vehicle control, an indomethacin group, and three experimental groups, named preventive, curative, and suppressive. All rats were sacrificed under deep ether anesthesia (6h) after the last oral administration of indomethacin/infusion. The rat stomachs were promptly excised, weighed, and chilled in ice-cold and 0.9% NaCl. Histological analysis, nitrites quantification and immunodetection assays were done. RESULTS B. scordioides infusions markedly reduced the visible hemorrhagic lesions induced by indomethacin in rat stomachs, also showed down-regulation of COX2, IL-8 and TNFα and up-regulation of COX-1 with a moderate down-regulation of NFkB and lower amount of nitrites. However, this behavior was dependent on the treatment, showing most down-regulation of COX-2, TNFα and IL-8 in the curative treatment; more down-regulation of NF-kB in the preventive treatment; and more up-regulation of COX-1 for the suppressor and preventive treatments. CONCLUSION The anti-inflammatory potential of B. scordioides infusions could be related with the presence of polyphenols as quercetin in the infusion and how this one is consumed.