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Functional foods have been used worldwide since ancient times, particularly, the prehispanic civilizations used several plants as medicinal foods. Nowadays, many Mexicans populations preserve their traditions and dietary patterns based on corn, beans, besides other endemic vegetables, mainly diverse varieties of chili, tomatoes and other plant-foods. It is well known that each species has a special complex mixture of bioactive compounds (BC) in which each component contributes to its overall bioactivity. These BC are plant metabolites that benefit human health by means of anti-inflammatory, immune-modulatory, and antioxidant effects. However, it becomes bioactive at human body when these BC must undergo diverse intestinal transformations, due to the action of digestive enzymes, but also by the action of microbiota metabolism. Thus, the intestinal microbiota is the key factor in the mediation of the physiological functions of dietary polyphenols. In fact, limited information is available, especially on dietary phytochemicals and metabolism in commonly available Mexican plant-foods. In this review, the bioaccesibility and bioavailability major BC from traditional Mexican plant-foods products and its potential health benefits will be discussed. Besides, we compile the scientific reports and the evidence of the impact of some Mexican plant-foods on the gut microbiota dynamic composition, specific microbial metabolites and its possible contributions to human health., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

"Quelites" are edible plants that are part of the traditional agro-ecosystems in Mexico. These plants, despite their already known nutritional properties, are now considered neglected and underutilized species. With the objective of promoting their reinsertion in the markets and mainly, in daily diets, efforts have been made to study them from multidisciplinary approaches to demonstrate their beneficial properties. To generate evidence of an added health-promoting value that would encourage quelites consumption, in the present work, the anti-Helicobacter pylori activity of three representative quelite species, Anoda cristata (Alache), Cnidoscolus aconitifolius (Chaya), and Crotalaria pumila (Chepil), was tested. H. pylori is considered the etiological agent of gastritis, ulcer, and gastric cancer, and represents a public health problem in Mexico and worldwide. Aqueous (AQ) and dichloromethane-methanol (DM) extracts were obtained from the three species of quelites to investigate their effect on H. pylori growth and on two of its colonization factors (adherence and urease activity). DM extracts from Chaya, Chepil, and Alache exert the best inhibitory effect on bacterial growth, with minimum inhibitory concentrations of 62.5, 125, and 250 μg/mL, respectively. AQ and DM extracts inhibit bacterial adhesion by 30% to 50%. None of them has an effect on urease activity. The two flavonoids present in A. cristata, acacetin and diosmetin, inhibit H. pylori growth by ∼90% with 3.9 μg/mL. These results provide new information about the anti-H. pylori potential of three edible quelites, and give an added value, since their routine consumption may impact on the prevention and/or control of H. pylori-associated diseases.

Spices are aromatic plants that have been widely used in Mexico to preserve or seasoning different foods, but have also been used as herbal remedies to cure some diseases. These culinary and medicinal properties of spices have been attributed to several food components, including phytochemicals. Among them, polyphenolic compounds have been extensively studied for their effect against several chronic and degenerative diseases, probably due to their antioxidant activity. The study of the antioxidant capacity of Mexican spices may lead to new research on the potential benefits of these spices on human health. This paper analyzes the main studies on the potential beneficial effects of traditional Mexican spices on human health., (Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.)

Jatropha curcas L. has been promoted as an oilseed crop for use to meet the increased world demand for vegetable oil production, and in particular, as a feedstock for biodiesel production. Seed meal is a protein-rich by-product of vegetable oil extraction, which can either be used as an organic fertilizer, or converted to animal feed. However, conversion of J. curcas seed meal into animal feed is complicated by the presence of toxins, though plants producing "edible" or "non-toxic" seeds occur in Mexico. Toxins present in the seeds of J. curcas include phorbol esters and a type-I ribosome inactivating protein (curcin). Although the edible seeds of J. curcas are known to lack phorbol esters, the curcin content of these seeds has not previously been studied. We analyzed the phorbol ester and curcin content of J. curcas seeds obtained from Mexico and Madagascar, and conclude that while phorbol esters are lacking in edible seeds, both types contain curcin. We also analyzed spatial distribution of these toxins in seeds. Phorbol-esters were most concentrated in the tegmen. Curcin was found in both the endosperm and tegmen. We conclude that seed toxicity in J. curcas is likely to be due to a monogenic trait, which may be under maternal control. We also conducted AFLP analysis and conclude that genetic diversity is very limited in the Madagascan collection compared to the Mexican collection., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Unlabelled: Campylobacter spp. is recognized as one of the most common cause of food-borne bacterial gastroenteritis in humans. Campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery-type illnesses with severe complications, such as Guillian-Barre syndrome. Epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been proposed to be critical steps in pathogenesis. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. In this study, 28 edible or medicinal plants species were analyzed for their bactericidal effects on the growth of Campylobacter jejuni and C. coli. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus-indica, and Cynara scolymus were the most effective against these microorganisms at minimal bactericidal concentrations (MBCs) of 0.3, 0.5, 0.4, and 2.0 mg/mL, respectively. No effect on growth was detected with lower concentrations of extract (25%, 50%, or 75% of the MBC) added to the media. The effect of each extract (75% of the MBC) on adherence and cytotoxicity of C. jejuni and C. coli was evaluated in Vero cells. Adherence of Campylobacter to Vero cells was significantly affected by all the extracts. Cytotoxic activity of bacterial cultures was inhibited by A. farnesiana and A. ludoviciana. These plant extracts are potential candidates to be studied for controlling Campylobacter contamination in foods and the diseases associated with this microorganism., Practical Application: Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus-indica, and Cynara scolymus were the most effective against these microorganisms. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces which are critical steps in pathogenesis were decreased by these extracts. Our results point to these plants as potential candidates for the control of Campylobacter contamination in foods, the treatment of the diseases associated with this microorganism, and as feed supplements to reduce on-farm prevalence of Campylobacter., (© 2011 Institute of Food Technologists®)

We evaluated the antiproliferative effect of aqueous extracts of 14 plant foods consumed in Mexico on the breast cancer cell line MCF-7. The plant foods used were avocado, black sapote, guava, mango, prickly pear cactus stems (called nopal in Mexico, cooked and raw), papaya, pineapple, four different cultivars of prickly pear fruit, grapes and tomato. β-Carotene, total phenolics and gallic acid contents and the antioxidant capacity, measured by the ferric reducing/antioxidant power and the 2,2-diphenyl-1,1-picrylhydrazyl radical scavenging assays, were analyzed in each aqueous extract. Only the papaya extract had a significant antiproliferative effect measured with the methylthiazolydiphenyl-tetrazolium bromide assay. We did not notice a relationship between the total phenolic content and the antioxidant capacity with antiproliferative effect. It is suggested that each extract of plant food has a unique combination of the quantity and quality of phytochemicals that could determine its biological activity. Besides, papaya represents a very interesting fruit to explore its antineoplastic activities.

137Cs and 40K specific activity together with major and trace elements were determined in soil samples and in different edible wild mushroom species collected from a seminatural temperate forest ecosystem located in the central part of the Mexican Volcanic Belt. The activity measurements were made using a gamma-ray spectrometer system with a high purity germanium (HpGe) detector. The major and trace elements were determined using emission spectrography and mass spectrometry, respectively. The aggregated transfer factors for 137Cs were estimated in 30 local mushroom species collected from 1993 to 1999. Differences as large as three orders of magnitude were observed. The contribution of mushrooms for the total 137Cs dietary intake by the local population was estimated to be 37%. Mushrooms also showed to be good accumulators for Rb, Cu, Cs and Se.

We analyzed the intake of selected foods that contain phytoestrogens in relation to breast cancer (BC) risk using data from a hospital-based case-control study performed in Mexico City from 1994 to 1995. A total of 198 women with BC, aged 21-79 years, were individually age matched to an identical number of women with no breast disease. By a direct interview, information on socioeconomic characteristics and diet was obtained. A semiquantitative questionnaire was used to estimate the frequency of consumption of 95 foods. The effect of selected foods that contain phytoestrogens on BC risk was estimated using logistic regression models. The adjusted odds ratio for the consumption of more than one slice of onion per day and BC was 0.27 (95% confidence interval = 0.16-0.47), with a statistically significant trend (p < 0.001). This protective effect remained after adjustment for known risk factors of BC. Among premenopausal women, there was also a protective and significant effect due to the intake of lettuce and spinach and nonsignificant protective effects for the consumption of apples and herbal tea. Additional studies aimed at evaluating the potential protective effect of particular phytoestrogens on BC risk are needed.

The protein quality of fruits bodies of three Pleurotus ostreatus Mexican strains (INIREB-8, CDBB-H-896 and CDBB-H-897) was evaluated. The protein concentration (Nx4.38) ranged from 17.26 to 19.97 g/100 g dry weight; chemical scores were between 74 and 93% with available lysine as a first limiting amino acid in either INIREB-8 and CDBB-H-896 strains or leucine in CDBB-H-897 strain. The nutritional evaluation revealed 67.75 to 68.38% in vitro digestibility. Relative protein values were from 100.06-107.85%, which were lower than soybean meal and whole egg but larger than those of rice, maize, beans, fava beans and pasta, no differences were found between these values and those of skim milk powder, casein plus methionine and albumin. In accordance with the last results we concluded that due to their essential amino acids content, mushroom proteins are a good complement of cereals; furthermore, it is highly recommended to include Pleurotus in the daily diet.

Cs-137 and K-40 have been determined in soil samples and in wild edible mushrooms from a forest ecosystem located at the Nuclear Centre of Mexico (NCM) and in several surrounding localities. The transfer factors for Cs-137 were studied in 21 mushroom species from 1993 to 1997. The Cs-137 and K-40 determinations were performed using a gamma spectrometer system of low level counting with a high purity germanium (HPGe) detector. The local mushroom species that were found to show higher Cs-137 transfer factors were Clavariadelphus truncatus, Cortinarius caerulescens, Gomphus floccosus and Lyophyllum decastes. The Cs-137 levels obtained at the NCM in some mushroom samples were slightly lower than those from surrounding localities indicating that the nuclear facility has not emitted Cs-137 to the atmosphere.

Seven seed samples of J. curcas, both in raw and roasted state, sold in some villages in Quintana Roo state, Mexico for human consumption were analyzed for physical characteristics, nutrients and antinutrients. The average seed weight varied from 0.53 to 0.74 g and kernel weight as proportion of raw seed weight was from 61 to 66%. The contents of crude protein, lipid and ash of kernels from raw seeds were 27-30%, 55-62% and 3.7-5.2% respectively. The levels of antinutrients in meal from the raw seeds were: trypsin inhibitor activity (14.6-28.7 mg trypsin inhibited/g), lectin (25.6-52.2 unit; one unit is the reverse of minimum amount of mg meal/ml assay which produced haemagglutination), saponins (1.9-2.3% as diosgenin equivalent) and phytate (8.4-10%). Phorbol esters in kernels from raw seeds were not detected in four samples and in other three samples it ranged from 0.01 to 0.02 mg/g as phorbol-12-myristate 13-acetate equivalent. Roasting of seeds inactivated almost 100% of trypsin inhibitor activity. Although lectin activity reduced on roasting, it was still present in high amounts. Saponins, phytate and phorbol esters were not affected by roasting.

The anti-hyperglycemic effect of 12 edible plants was studied on 27 healthy rabbits, submitted weekly to subcutaneous glucose tolerance tests after gastric administration of water, tolbutamide or a traditional preparation of the plant. Tolbutamide, Cucurbita ficifolia, Phaseolus vulgaris, Opuntia streptacantha, Spinacea oleracea, Cucumis sativus and Cuminum cyminum decrease significantly the area under the glucose tolerance curve and the hyperglycemic peak. Brassica oleracea var. botrytis, Allium cepa and Allium sativum only decrease the hyperglycemic peak. The glycemic decreases caused by Psidium guajava, Brassica oleracea and Lactuca sativa var. romana were not significant (P > .05). The integration of a menu that includes the edible plants with hypoglycemic activity for the control and prevention of diabetes mellitus may be possible and recommendable.

The study of Atriplex suberecta leaf protein concentrate has been included within our work line entitled "Biological value of the leaf protein of Atriplex" amino acid profile and chemical score. In order to evaluate nitrogen retention, net protein utilization (NPU), true digestibility (TD) and biological value (BV) data were obtained. Weight gain was studied after determining net protein ratio (NPR) and relative net protein ratio (RNPR) with the following results: CS = 96, calculated for sulphur amino acids; NPU = 60 +/- 4.00; TD = 76 +/- 5.20; BV = 87; NPR = 3.34 +/- 2.50 and RNPR = 88%, which enable us to infer that its protein is of good quality. These data, therefore, should indicate that the product studied could be a good complement for cereals, considering its high lysine content (CS superior to 100).