Ruth E. Belmares-Cerda

Ultrasound-assisted extraction of phenolic compounds from Laurus nobilis L. and their antioxidant activity.

Bay leaves (BL) (Laurus nobilis L., Family: Laureceae) are traditionally used to treat some symptoms of gastrointestinal problems, such as epigastric bloating, impaired digestion, eructing and flatulence. These biological properties are mainly attributed to its phenolic compounds. In this paper, ultrasound-assisted extraction of phenolic compounds from Laurus nobilis L. (Laureceae) was studied. Effects of several experimental factors, such as sonication time, solid/liquid ratio and concentration of solvent on extraction of phenolic compounds were evaluated through a randomized complete block design with factorial treatment arrangement (3(3)). The best extraction conditions were: 1g plant sample with 12 mL of 35% ethanol, for 40 min, obtaining a yield of phenolic compounds of 17.32±1.52 mg g(-1) of plant. In addition, free radical-scavenging potential of DPPH and lipid oxidation inhibition, by linoleic acid peroxidation of the selected extract was measured in order to evidence their antioxidant properties. Results indicated that high amounts of phenolic compounds can be extracted from L. nobilis by ultrasound-assisted extraction technology.

Production of thermostable xylanase by thermophilic fungal strains isolated from maize silage

The search for microorganisms able to produce thermostable xylanases with high yield and characteristics desired for industrial applications has been strongly encouraged since such enzymes are widely used in large-scale processes. In the present study, thermophilic fungal strains able to grow at high temperatures (≥55 °C) were isolated from maize silage. The strains were molecularly identified and used for the production of extracellular xylanase by solid-state fermentation using corn cobs as support-substrate material. Species from the genera Rhizomucor and Aspergillus were identified among the isolated strains and these species demonstrated good ability to produce xylanase under solid-state fermentation conditions. Maximal values of enzymatic activity (824 U/g) and productivity (8.59 U/g.h) were obtained with Rh. pusillus SOC-4A (values per g dry weight of fermented medium). The xylanase produced by this fungus presented thermal stability at 75 °C, with maximum activity at 70 °C and pH 6.0, revealing, therefore, great potential for application in different areas.

Aloe vera and Probiotics: A New Alternative to Symbiotic Functional Foods

Providing products that beyond a high nutritional value brings health benefits to consumers is a major challenge to food industry. Functional foods, including prebiotics and probiotic as components, are the protagonists to promote these advantages. Aloe vera is a medicinal plant well characterized in terms of its chemical composition and therapeutic properties. Taking into account these characteristics Aloe vera represents an excellent natural source of prebiotics, as well as a substrate for lactic acid bacteria fermentation. Thus a symbiotic drink using Aloe vera as the main ingredient and lactic acid bacteria as probiotics with significant benefits to human health might represent a promising product to develop. Mini-review Article

Gallic Acid as a Putative Antioxidant in Usage Against Liver Disease

Abstract Hepatitis C virus (HCV) infection causes high level of oxidative stress and hepatic inflammation primarily, and derives in different pathologies as liver cirrhosis, hepatic failure, and hepatocellular carcinoma (HCC). Currently available treatment is a combination of pegylated interferon-α and ribavirin, surgical resection, and liver transplantation. However, more than 50% of patients remain diseased and the treatment prior mentioned causes serious adverse effects and there is still no preventive vaccine available. Considering the limited treatment options, it remains the urgent need to find additional therapeutic agents. Chemoprevention is defined as the use of nontoxic substances and it has been considered as the alternative strategy to reduce the cancer development and carcinogenesis before invasion and metastasis occur. Polyphenols, such as ellagic acid, ellagitannins, and punicalagin and phenolic acids, such as gallic acid are abundant plant phenolic compounds and they are extracted from different fruit peels and seed. Those kinds of compounds are known to reduce the risk of disease and have shown to induce cytotoxicity in several cancer cell lines, including liver cell lines. In vitro and in vivo studies have shown that the GA has a positive effect on various liver diseases, such as hepatitis by HCV infection, hepatocellular carcinoma, steatosis, and fatty liver. Histopathology and serum biochemical studies in mice fed with a diet supplemented with GA, observed that GA protects against hepatic steatosis, obesity, hypercholesterolemia, and insulin resistance. This effect occurs in part through a reversing of the common high fat diet that caused disturbances to a range of metabolic pathways, including lipid metabolism, glucose metabolism (glycolysis and gluconeogenesis), and amino acids metabolism. On the other hand, GA also has in vitro effect in hepatocarcinoma cells that express nonstructural proteins of HCV reducing viral replication. Viral proteins expression and the levels of oxidative stress decreases the viability of liver cancer cells in cell culture. Some of the main action mechanisms are the activation of protein kinase ATM, dehydrogenase UDP-glucose, and NFκB pathway. In addition, when glutathione is depleted, induction of apoptotic, antiangiogenic effect, and inhibition of tumor cell proliferation is activated. For these reasons, the use of antioxidant compounds, particularly gallic acid, has been studied recently because it is a naturally abundant plant phenolic compound, it may be considered a tool as a biomarker, or alternative therapy in the prevention and treatment of liver diseases.

Prebiotics, Probiotics, Synbiotics and Functional Foods in Control and Treatment of Type II Diabetes Mellitus and Colorectal Cancer

Prebiotics, probiotics and synbiotics are components that enhance human health by several mechanisms. Patients suffering from type II diabetes mellitus (T2DM) and colorectal cancer have seen benefits when treated with a prebiotic, probiotic or synbiotic therapy. These benefits include the improvement of their lipid profile, oxidative stress status, as well as the modulation of the inflammatory and immune responses. The associated benefits of prebiotic, probiotic or synbiotic functional foods have been studied, showing promising results into the prevention or control of diabetes and colorectal cancer. This novelty research provides new evidence that the use of functional foods along with medical therapy could be used to further enhance patient’s health.