Effect of Harpin protein as an elicitor on the content of phenolic compounds and antioxidant capacity in two hydroponically grown lettuce (Lactuca sativa L.) varieties.

Abstract Harpin protein was used as an elicitor in green (butterhead) and red (oak leaf type) varieties of hydroponically grown lettuce (Lactuca sativa L.). Its impact on polyphenolic content and antioxidant capacity was evaluated. Harpin protein was sprayed three days before harvesting in concentrations of 45, 60, and 120 mg/L. Green lettuce samples showed a positive response to Harpin by significantly increasing its phenolic content from 12 (control) to 16.43 mg gallic acid equivalents (GAE)/100 g dry weight (DW) (120 mg/L Harpin treatment) which means a 36.9% increase. Chlorogenic acid was the only phenolic compound that increased its concentration after lettuce induction with Harpin treatment. Antioxidant capacity, evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH˙) and ferric reducing antioxidant power (FRAP) methods, also showed a significant increase (46.5 and 64.3%, respectively) in Harpin-treated green lettuce. The red lettuce variety showed none or a negative response to Harpin treatment for all parameters evaluated. These results show that elicitation may be an effective strategy to enhance phenolic content in lettuce varieties

Cinética de secado y efecto de la temperatura sobre las características físicas y compuestos fenólicos de chile jalapeño rojo (Capsicum annuum L.)

En este trabajo se evaluó el impacto de cuatro diferentes temperaturas de secado sobre las características físicas y contenido de compuestos fenólicos de chile jalapeño rojo. Para ello se determinaron cinéticas de secado para cada temperatura ensayada (55, 65, 75 y 85°C), monitoreando la humedad residual. Así mismo, se evaluó el contenido de compuestos fenólicos, flavonoides, capacidad antioxidante y perfil de compuestos fenólicos en las muestras por HPLC/ MS-ESI-QTOF al inicio y al final de cada proceso de secado. A todas las temperaturas, las cinéticas de secado se ajustaron a los modelos de “Midilli”, “Wang” y “logarítmico”. El coeficiente efectivo de difusividad fue dependiente de la temperatura, obteniendo una energía de activación de 34.66 KJ/mol. Los parámetros colorimétricos se vieron modificados, reflejando la aparición de un color marrón en las muestras secas. El contenido de compuestos fenólicos, flavonoides y la capacidad antioxidante no varió durante el proceso de secado. Por HPLC-MS se identificaron 24 compuestos fenólicos: 13 ácidos fenólicos, 2 antocianinas y 9 flavonoides, mismos que se mantuvieron durante el secado

Seed Characteristics and Nutritional Composition of Pine Nut from Five Populations of <i>P. cembroides</i> from the States of Hidalgo and Chihuahua, Mexico

The aim of this study was to analyze the seed characteristics and nutritional composition of five pine nut P. cembroides samples from two Mexican states. Morphometry, proximal composition, phenolic compounds, and antioxidant capacity were determined. Samples differed in several morphometric trails, but important differences were documented between SMCH and JCZH samples from Hidalgo State. JCZH and FMH had the highest contents of water, lipids, protein, flavonoids, and antioxidant activity, while CMCC population from Chihuahua State had presented the highest content of ash and carbohydrates. Morphometry and chemical composition data were subjected to clustering analysis. This analysis showed that SMCH and LFCH from Hidalgo State were well separated from the JCZH and FMH populations from Hidalgo State, which showed a strong similarity between them, while the CMCC from Chihuahua State was the most distant population. Principal components analysis showed that the variables that strongly contributed to PC1 were the antioxidant activity determined by FRAP assay, flavonoids, and water content. These data have provided biochemical markers that could help to establish phylogenetic associations between populations, and also to reveal potentially account as an alternative source for dietary nutrition

Effect of Moringa oleifera seed extract on antimicrobial activity and in vitro fertilization ability of cryopreserved ram semen

Cryopreservation has adverse effects on the post-thaw sperm quality due to oxidative stress and the presence of bacteria. To minimize such effects, plant extracts have been included in the composition of the semen diluents. The objective of the present study was to evaluate the antimicrobial and antioxidant effects of Moringa oleifera seed extract (MOSE) on cryopreserved ram semen, as well as its impact on in vitro fertilization. Semen from six hair rams was treated with five treatments before cryopreservation: Control (without any antibiotic), Standard (conventional antibiotic), 1.0, 10.0, and 50.0 mg/ml of MOSE. Post-thawing sperm characteristics were evaluated by the computer-assisted semen analysis. Antimicrobial activity was assessed by counting colony-forming units (CFU) and the antioxidant capacity by the ferric reducing antioxidant power method. A heterologous in vitro fertilization technique was implemented to measure the fertilization rate. Progressive and rapid motility, membrane and acrosome integrity, and active mitochondria were higher (p < .05) in the 10.0 mg/ml treatment compared with Standard after thawing. All M. oleifera treatments showed inhibition of CFU. The antioxidant capacity of M. oleifera seed extract was higher in the 10.0 and 50.0 mg/ml treatments. Fertilization rate (cleavage percentage) was higher (p < .05) in the 10.0 mg/ml (82.9 ± 10.0) and Control (82.5 ± 9.9) treatments compared with Standard (73.7 ± 9.1). The addition of 10.0 mg/ml of MOSE to ram semen inhibits the development of microorganisms and improves sperm characteristics and the in vitro fertility of the semen

Incorporation of Moringa oleifera pods onto breads improves nutrient contents, phytochemicals bioaccessibility and reduces the predicted glycemic index

This work aimed to evaluate Moringa oleifera immature pod flour’s effect on the nutritional content and bioaccessibility of phytochemicals in partially substituted wheat flour breads. Different bread preparations were made and the most accepted formulation by panelists was chosen for this study. The composition of macro-components, the content of polyphenolic compounds, and the antioxidant capacity of the samples were measured. The bioaccessibility of polyphenolic compounds associated with dietary fiber was also analyzed. Finally, an in vitro kinetics on the release of the polyphenolic compounds was conducted. Breads containing 13% of flour from M. oleifera immature pods presented the highest acceptance among the substituted breads; meantime, its dietary fiber content was three times higher than white breads. Also, the content of polyphenolic compounds and the antioxidant capacity was higher in the substituted bread, compared to the white ones. Soluble fiber correlated with the increase of polyphenolic compound concentrations in both substituted and white breads. The most significant in vitro release of phenolic compounds was shown in those prepared with M. oleifera. Taken together, the results demonstrated that breads partially substituted with M. oleifera pod flour exhibited the highest nutrient and phytochemical content along with a better bioaccessibility.Keywords: Dietary fiber; Functional food; Non-conventional food; Wheat-based bread; Polyphenolic compound

Incorporation of Moringa oleifera pods onto breads improves nutrient contents, phytochemicals bioaccessibility and reduces the predicted glycemic index

This work aimed to evaluate Moringa oleifera immature pod flour’s effect on the nutritional content and bioaccessibility of phytochemicals in partially substituted wheat flour breads. Different bread preparations were made and the most accepted formulation by panelists was chosen for this study. The composition of macro-components, the content of polyphenolic compounds, and the antioxidant capacity of the samples were measured. The bioaccessibility of polyphenolic compounds associated with dietary fiber was also analyzed. Finally, an in vitro kinetics on the release of the polyphenolic compounds was conducted. Breads containing 13% of flour from M. oleifera immature pods presented the highest acceptance among the substituted breads; meantime, its dietary fiber content was three times higher than white breads. Also, the content of polyphenolic compounds and the antioxidant capacity was higher in the substituted bread, compared to the white ones. Soluble fiber correlated with the increase of polyphenolic compound concentrations in both substituted and white breads. The most significant in vitro release of phenolic compounds was shown in those prepared with M. oleifera. Taken together, the results demonstrated that breads partially substituted with M. oleifera pod flour exhibited the highest nutrient and phytochemical content along with a better bioaccessibility.Keywords: Dietary fiber; Functional food; Non-conventional food; Wheat-based bread; Polyphenolic compound

Inhibition of Urease by Disulfiram, an FDA-Approved Thiol Reagent Used in Humans

Urease is a nickel-dependent amidohydrolase that catalyses the decomposition of urea into carbamate and ammonia, a reaction that constitutes an important source of nitrogen for bacteria, fungi and plants. It is recognized as a potential antimicrobial target with an impact on medicine, agriculture, and the environment. The list of possible urease inhibitors is continuously increasing, with a special interest in those that interact with and block the flexible active site flap. We show that disulfiram inhibits urease in Citrullus vulgaris (CVU), following a non-competitive mechanism, and may be one of this kind of inhibitors. Disulfiram is a well-known thiol reagent that has been approved by the FDA for treatment of chronic alcoholism. We also found that other thiol reactive compounds (l-captopril and Bithionol) and quercetin inhibits CVU. These inhibitors protect the enzyme against its full inactivation by the thiol-specific reagent Aldrithiol (2,2′-dipyridyl disulphide, DPS), suggesting that the three drugs bind to the same subsite. Enzyme kinetics, competing inhibition experiments, auto-fluorescence binding experiments, and docking suggest that the disulfiram reactive site is Cys592, which has been proposed as a “hinge” located in the flexible active site flap. This study presents the basis for the use of disulfiram as one potential inhibitor to control urease activity