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Evaluation of Oxidative Stress in Cardiomyocytes during the Aging Process in Rats Treated with Resveratrol

The substantial increase in the number of elderly people in our societies represents a challenge for biology and medicine. The societies of the industrialized countries are subject to a progressive aging process that translates into an increase in the cardiovascular risk of the population. In the present work, the activity of catalase and superoxide dismutase was evaluated, as well as markers of oxidative stress (concentration of nitric oxide and total lipoperoxidation in its main components: malondialdehyde and 4-hydroxyalkene) in cardiomyocytes during the aging process in rats treated with resveratrol. Rats were divided into 4 groups according to the following categories: control (without treatment), negative control group (administered with physiological solution with 10% ethanol), positive control group (administered with vitamin E, 2 mg/kg/day), and group administered with resveratrol (10 mg/kg/day); these groups in turn were divided into 2, 4, 6, and 8 months of treatment. The analysis of nitric oxide showed a decreased level in the cardiac tissue in the groups treated with resveratrol; the same occurs when total lipoperoxidation is analyzed. The enzymatic activity studied (catalase and superoxide dismutase) did not present significant changes with respect to the controls. It is concluded that the cardioprotective effect of resveratrol is due to the antioxidant effect and other antiaging effects and not to the activation of the enzymes catalase and superoxide dismutase.

Growth modeling to control ( in vitro ) Fusarium verticillioides and Rhizopus stolonifer with thymol and carvacrol

The aim of this study was to evaluate the antifungal activity (in vitro) of thymol and carvacrol alone or in mixtures against Fusarium verticillioides and Rhizopus stolonifer, and to obtain primary growth models. Minimal inhibitory concentration (MIC) was evaluated with fungal radial growth with thymol or carvacrol concentrations (0-1600mg/l). Mixtures were evaluated using concentrations below MIC values. Radial growth curves were described by the modified Gompertz equation. MIC values of carvacrol were 200mg/l for both fungi. Meanwhile, MIC values of thymol were between 500 and 400mg/l for F. verticillioides and R. stolonifer, respectively. A synergistic effect below MIC concentrations for carvacrol (100mg/l) and thymol (100-375mg/l) was observed. Significant differences (p<0.05) between the Gompertz parameters for the antimicrobial concentrations and their tested mixtures established an inverse relationship between antimicrobial concentration and mycelial development of both fungi. Modified Gompertz parameters can be useful to determine fungistatic concentrations.

Chapter 47 – Combinational Approaches for Antimicrobial Packaging: Chitosan and Oregano Oil

Abstract The aim of this chapter is to present recent advances regarding chitosan and oregano essential oil as well as approaches of their combination for antimicrobial packaging. Materials currently utilized for the manufacture of food packaging can be replaced by biopolymers (including chitosan) because some of their properties are similar to those of synthetic polymers. Furthermore, there could be mixtures of different biopolymers or mixtures thereof with synthetic polymers; selection of mixtures depends on needed application and type of food product to be packaged. Barrier properties (water vapor, oxygen, and carbon dioxide permeability) and mechanical properties (tensile strength and elongation) will determine the feasibility of formed films to meet desired functionality for the product to be packed. Chitosan is, after cellulose, one of the most abundant biopolymers in nature, with antimicrobial, antioxidant, and antiviral properties. When combined with oregano essential oil that has antimicrobial and antioxidant activities, it may produce effective edible films and packaging materials.

Effect of pH and Mexican Oregano (Lippia berlandieri Schauer) Essential Oil Added to Carboxymethyl Cellulose and Starch Edible Films on Listeria monocytogenes and Staphylococcus aureus

The aim of this work was to evaluate the effect of pH and Mexican oregano essential oil (MOEO) added to carboxymethyl cellulose (CMC) and starch (S) edible films on Listeria monocytogenes and Staphylococcus aureus. CMC and S edible films were formulated with different concentrations (0%, 0.25%, 0.50%, 0.75%, and 1%) of MOEO at different pH (5, 6, or 7). Antimicrobial assay was performed. Inhibition curves were fitted to the Fermi model. Significant differences ( ) were found in tc (time to reduce 50% of microbial population) and (slope of the curve around ), being lower at acidic pH. For L. monocytogenes, CMC films exhibited a higher antimicrobial effectiveness (0.50% of MOEO) compared to S films which need a higher concentration of MOEO (0.75%). S. aureus was inhibited with CMC films at 0.50% MOEO and pH 5 and 6. Microbial modeling has allowed estimating key intrinsic factors as pH and MOEO concentration with the synergistic effect against two important food-borne pathogens.

Biotic and Abiotic Factors to Increase Bioactive Compounds in Fruits and Vegetables

Abstract Plants, including fruits and vegetables contain a high amount of phytonutrients, biologically active compounds resulting from their secondary metabolism, which represent an important source of pharmaceuticals or nutraceutics. Historical documents indicate the use of plants to obtain medications and their use for several therapies; nowadays, approximately 25% of commercial drugs are derived from plants. These metabolites perform a significant role in plants’ adaptation and they are responsible of plant protection from different biotic or abiotic stress factors. These substances promote a defense response of plants, involving genes that encode proteins to repair and prevent cell damage, enhance the fortification of cell wall and middle lamella, produce protease inhibitors and lytic enzymes, as well as synthesize secondary metabolites with antimicrobial and antioxidant characteristics, among other responses. There are more than 200,000 known plant secondary metabolites with different functions. Therefore, the aim of this chapter is to revise, analyze, and describe the most important biotic and abiotic factors, emphasizing current investigations regarding the effect of novel methods to increase secondary metabolites in fruits and vegetables.