Functional Foods, Nutraceuticals and Probiotics: A Focus on Human Health.

Functional foods are classified as traditional or staple foods that provide an essential nutritional level and share potentially positive effects on host health, including the reduction of disease by optimizing the immune system's ability to prevent and control infections by pathogens, as well as pathologies that cause functional alterations in the host. This chapter reviews the most recent research and advances in this area and discusses some perspectives on what the future holds in this area.

Antioxidant and Anti-Inflammatory Properties of Probiotic Candidate Strains Isolated during Fermentation of Agave (Agave angustifolia Haw).

Agave species are a source of diverse products for human use, such as food, fiber, and beverages, which include mezcal, a distilled beverage produced by spontaneous fermentation. Agave is an excellent source of high amounts of sugars, minerals, and phenolic compounds, which favor the growth of lactic acid bacteria (LAB) and yeast communities. In this work, 20 promising LAB strains with probiotic characteristics were isolated from the agave fermentation stage in mezcal production. The strains belonged to Lactobacillus plantarum (15), Lactobacillus rhamnosus (2), Enterococcus faecium (2), and Lactococcus lactis (1). These isolates were characterized for their resistance under gastrointestinal conditions, such as lysozyme, acid pH, and bile salts. In addition, the adherence of these LABs to human intestinal epithelial cells (Caco-2 and HT-29 cells) was tested in vitro and their antioxidant and immunomodulatory profile was determined using cellular models. Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 and LM19 strains were selected for their antioxidant properties, and their capacities in an oxidative stress model in intestinal epithelial cells IECs (Caco-2 and HT-29 cells) in the presence of hydrogen peroxide were evaluated. Interestingly, Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 and LM19 strains showed anti-inflammatory properties in TNF-α-stimulated HT-29 cells. Subsequently, bacterial strains exhibiting antioxidant and anti-inflammatory properties were tested in vivo in a mouse model with dinitrobenzene sulfonic acid (DNBS)-induced chronic colitis. Weight loss, intestinal permeability, and cytokine profiles were measured in mice as indicators of inflammation. One of the selected strains, Lactobacillus plantarum LM17, improved the health of the mice, as observed by reduced weight loss, and significantly decreased intestinal permeability. Altogether, our results demonstrate the potential of LAB (and lactobacilli in particular) isolated from the agave fermentation stage in mezcal production. Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 strains represent potential candidates for developing new probiotic supplements to treat inflammatory bowel disease (IBD).

Pretreatment of tamarind pericarp to increase antioxidant availability and its application in a functional food.

Diverse researchers have considered by-products of food and agricultural processing industries as a source of antioxidants. Tamarind (Tamarindus indica) is a leguminous tree, native from tropical Africa bearing edible fruit. The fruit is composed of 30% pulp, 40% seed, and 30% pericarp. Currently, tamarind pericarp is a waste from tamarind processing (approximately 54,400 tons of pericarp in 2012 worldwide) and is contributing to environmental contamination. This research aimed to determine the effect of maceration, microwaves, and ultrasound on the increase in the antioxidant availability in tamarind pericarp and its incorporation as a functional ingredient in cookies (5 and 10% substitution). Antioxidant content, antioxidant activity, proximate, and sensorial analysis of the cookies were conducted. The microwave method was the best pretreatment compared with sonication and maceration since it showed 1.3-fold higher amounts of phenolic compounds and 1.2-fold higher antioxidant capacity. The 10% substitution of tamarind pericarp powder in cookies, significantly increased the fiber content (four-fold) and phenolic compounds content (2.6-fold) and the product presented good acceptance in a sensorial test. Thus, tamarind pericarp powder could be considered as an antioxidant and fiber source and could be used as a functional ingredient in food products.

Obesity and Cardiovascular Risk Improvement Using Cacao By-Products in a Diet-Induced Obesity Murine Model.

In the production of chocolate, only cocoa seeds are used, generating by-products that are generally discarded, increasing the risk of environmental contamination. Given fiber, carbohydrates, proteins, and flavonoid content the use of cacao pod husks can generate nutraceutical products for human consumption. In contrast, obesity represents a major public health problem worldwide. Cacao derivatives are able to modulate overweight and lipid disorders. The objective of present work was to prepare and characterize products using cacao by-products and analyze their effects on altered cardiometabolic risk markers in an obesity model induced by high fat diet and fructose ingestion in rats. The effects of a pellet and extracts made with outer pod husk and kernel husk for 5 weeks were analyzed in an obesity rat model. The treatments significantly decreased body weight by 39%, systolic blood pressure by 27%, triglycerides by 55%, total cholesterol by 24%, low-density lipoprotein cholesterol by 37%, and the triglycerides/high-density lipoprotein ratio by 54%. Cacao by-products improved the metabolic function of obese animals, without causing secondary effects.

Identification of novel anti-inflammatory probiotic strains isolated from pulque.

Probiotics are live microorganisms which when administered in adequate amounts, confer health benefits on the host. Their use is more and more widespread for both prevention and treatment of diseases, including traveler's diarrhea and inflammatory bowel diseases (IBDs). In this work, we isolated and characterized novel candidate probiotic strains from pulque (xaxtle), a traditional Mexican alcoholic fermented beverage. A total of 14 strains were obtained from xaxtle samples isolated from three different Mexican regions. Species identification was performed by biochemical methods and 16S rRNA gene targeted PCR. The isolates belonged to the Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus composti phylogenetic groups, with L. brevis being the most dominant group. Bacteria were tested for lysozyme, low pH, and bile acid resistance. Moreover, the strains were tested for adherence to human intestinal epithelial cells and screened for their immunomodulatory properties using a cellular model. Selected bacterial strains with anti-inflammatory properties were then tested in vivo in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis mouse model, and weight loss, gut permeability, and cytokine profiles were measured as readouts of inflammation. One of the selected strains, Lactobacillus sanfranciscensis LBH1068, improved mice health as observed by a reduction of weight loss, significant decreases in gut permeability, and cytokine modulation. Altogether, our results highlighted the potential of lactobacilli isolated from pulque and in particular the strain L. sanfranciscensis LBH1068 as a novel probiotic to treat IBD.

In vitro starch digestibility and expected glycemic index of pound cakes baked in two-cycle microwave-toaster and conventional oven.

Bread baking technology has an important effect on starch digestibility measured as its predicted glycemic index tested in vitro. The aim of this work was to evaluate the changes in predicted glycemic index of pound cake baked in a two-cycle microwave toaster and a conventional oven. The glycemic index was calculated from hydrolysis index values by the Granfeldt method. Non-significant differences (P > 0.05) were found in hydrolysis index (60.67 ± 3.96 for the product baked in microwave oven and 65.94 ± 4.09 for the product baked in conventional oven) and predicted glycemic index content (60.5 for product baked in microwave oven and 65 for the product baked in conventional oven) in freshly-baked samples. Results clearly demonstrate that the baking pound cake conventional process could be replicated using a two-cycle multifunction microwave oven, reducing the traditional baking time. Further research is required in order to achieve pound cake crumb uniformity.

In vitro starch digestibility and predicted glycemic index of microwaved and conventionally baked pound cake.

The present study compares the effect of baking process (microwave vs conventional oven) on starch bioavailability in fresh pound cake crumbs and in crumbs from pound cake stored for 8 days. Proximal chemical analysis, resistant starch (RS), retrograded starch (RS3) and starch hydrolysis index (HI) were evaluated. The empirical formula suggested by Granfeldt was used to determine the predicted glycemic index (pGI). Pound cake, one of Mexico's major bread products, was selected for analysis because the quality defects often associated with microwave baking might be reduced with the use of high-fat, high-moisture, batted dough. Differences in product moisture, RS and RS3 were observed in fresh microwave-baked and conventionally baked pound cake. RS3 increased significantly in conventionally baked products stored for 8 days at room temperature, whereas no significantly changes in RS3 were observed in the microwaved product. HI values for freshly baked and stored microwaved product were 59 and 62%, respectively (P > 0.05), whereas the HI value for the conventionally baked product decreased significantly after 8 days of storage. A pound cake with the desired HI and GI characteristics might be obtained by adjusting the microwave baking process.