Selected Mesoamerican Crops - Anti-Obesity Potential and Health Promotion. A Review.

Mesoamerica is the center of origin of a great number of food crops that nowadays are part of a healthy diet. Pre-Columbian civilizations utilized more than 90% of these foods as ingredient or in main dishes, as well as for remedies and religious ceremonies. Since several years ago, Mesoamerican foods have been recognized by their outstanding concentration of bioactive compounds, including, phenolic compounds, pigments, essential fatty acids, amino acids, peptides, carbohydrates and vitamins, which provide a great number of health benefits. As a result of their unique composition, these ancient crops have several positive effects, such as hypoglycemic, antioxidant, anti-obesity, anti-inflammatory, anti-ageing, neuroprotective, anti-diarrheal, and anti-hypercholesterolemic capacity. Hence, this review is focused mainly in the anti-obesity and antioxidant potential of some of the most cultivated, harvested, as well as commercialized and consumed, food crops native of Mesoamerica, like, nopal and its fruit (Opuntia ficus indica spp.), chia (Salvia hispanica L.), pumpkin (Cucurbita spp.) and cacao (Theobroma cacao).

Fruits of Wild-Grown Shrubs for Health Nutrition.

Cultivated fruits and berries, such as raspberries, strawberries, black currants, cherries, blueberries, are generally recognized sources of antioxidants, vitamins, minerals, and other substances beneficial to human health and well-being. However, there are also wild berries and fruits that are of undoubted interest as food products having valuable medicinal properties due to the presence of phenolic compounds, antioxidants, and vitamins. These fruits have a great potential to be used in functional food making. The present review is dedicated to fruits of wild-grown shrubs Bird cherry (Prunus padus L.), Rowan berry (Sorbus aucuparia L.), Guelder rose (Viburnum opulus L.), Black elderberry (Sambucus nigra L.), and Barberry (Berberis vulgaris L.) The chemical compositions of these wild berries are described as well as their effects on the improvement of human health proved by clinical trials and epidemiological studies. The possibilities of using the fruits of wild-grown shrubs in the preparation of functional foods and examples of their implementation for the manufacturing of dairy, bakery and meat products are considered.

Seeds from ancient food crops with the potential for antiobesity promotion.

Populations like to have a healthy diet without changing their fundamental dietary pattern. The importance of dietetic foods with health potential has increased the interest of consumers on crops with nutraceutical messages. Several plant food products from selected ancient crops like flax, chia, black cumin, sunflower, sesame, and pumpkin seeds contain substances with high health benefits. These crops are usually rich sources in fatty acids, sterols, phenolic compounds and dietary fiber which have mainly shown the ability to increase satiety and obesity control, among chronic degenerative diseases and others. These plant seeds offer outstanding features for the food and nutraceutical industries, due to their functional components. This review focuses on scientific evidence of the different potential benefits of these crops on human antiobesity promotion.

New Advances in Short Peptides: Looking Forward.

It is beyond doubt that short peptides hold significant promise in bio-medicine, as the most versatile molecules, both structurally and functionally [...].

Capsicum annuum (hot pepper): An ancient Latin-American crop with outstanding bioactive compounds and nutraceutical potential. A review.

Hot pepper (Capsicum annuum) fruits, usually termed as chili, have been used since ancient times as food vegetables, flavoring ingredients, natural colorants, and in traditional medicines. Nowadays, a wide variation of sweet and pungent peppers are consumed worldwide in a large variety of forms. Interestingly, the most important hot pepper at the global level in commercial terms is C. annuum with a high number of varieties. This review compares C. annuum to other Capsicum species for plant agronomic traits, biochemical composition, the content of capsaicin and capsaicinoids and their nutraceutical and medical potentialities, and the effects of processing on quality and key components of the fruit, among other aspects. Chili contains important levels of pigments (i.e., chlorophyll, anthocyanin, and lutein) with potential health benefits; it also contains additional outstanding health-promoting chemical compounds, such as vitamins, minerals, flavonoids, carotenoids, and capsaicinoids, in general. And capsaicin, the major active compound responsible for the pungent taste of these species has been proven to have a positive role in health. We report here on how dietary chili and capsaicinoids consumption, especially capsaicin, are involved in body weight reduction and their potential antiobesity effects, in urinary disorders, as well as antioxidants, antimicrobial, anticancer, and analgesic capacity. Selected characteristics of processing for the fruit preservation on its quality and content of these compounds are described as well. However, additional clinical research on the mechanism of action and efficacy of frequent capsaicinoid consumption on human health is needed.

Bioactive peptides from selected latin american food crops - A nutraceutical and molecular approach.

This review reported an updated survey on the molecular functional properties of bioactive peptides derived from different Latin American ancient grains such as Maize, common Bean, Amaranth, Quinoa and Chia seeds. Seed storage proteins ecrypt in their sequences diverse peptides associated with a wide range of beneficial effects on the human health and the most studied are antihypertensive, anti-cholesterolemic, antioxidant, anti-inflammatory, anticancer, antimicrobial and immunomodulatory properties. Additionally, in the last decades molecular properties have been also used for their characterization to understand their activities and it makes them highly attractive to be incorporated into food formulations and to complement or replace some conventional cereal grains. Due to the nutraceutical effects, today, these seeds are one of the main gastronomic trends of consumption worldwide due to their nutritional benefits and are part of the shopping lists of many people, among them vegetarians, vegans, celiacs or lovers of raw food. These seeds are a legacy of pre-Columbian civilizations reason why in our time they are considered as "Superfoods of the Gods", "The pre-hispanic superfoods of the future" and "The new golden seeds of the XXI century".

Antioxidant and Antihypertensive Potential of Protein Fractions from Flour and Milk Substitutes from Canary Seeds (Phalaris canariensis L.).

Canary seed (Phalaris canariensis) is used to feed birds but it has been recently considered a promising cereal with nutraceutical potential for humans. The aim of this work was to analyze the protein fractions from canary seed flour and from milk substitutes (prepared by soaking the seeds in water 12 and 24 h), and to evaluate antioxidant and antihypertensive capacity of peptides obtained after in vitro digestion. Prolamins were the major protein fraction, followed by glutelins. After digestion, albumins and prolamins fractions from milks presented higher levels of peptides than flour, globulins showed more peptides in flour and glutelins were found in similar concentrations in all samples; 24 h milk prolamins had the highest concentration of peptides. Purification by high performance liquid chromatography (HPLC), sequencing of peptides, in vitro antioxidant ABTS (2,2'-azino-bis, 3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays, and antihypertensive capacity (angiotensin converting enzyme (ACE) assay), indicated that peptides from canary seed prolamins were the most efficient compounds with antioxidant and antihypertensive activity. Canary seeds may be considered an accessible and cheap source to prepare milk substitutes with high contents of bioactive peptides with remarkable functional properties to promote better human health and healthy ageing.

Phenolic Compounds, Antioxidant Activity and Lipid Profile of Huitlacoche Mushroom (Ustilago maydis) Produced in Several Maize Genotypes at Different Stages of Development.

Huitlacoche mushroom (composed by the fruiting bodies growing on the maize ears from the basidiomycete Ustilago maydis) is a culinary delicacy with a great economic and nutraceutical value. In this work, phenolic content, antioxidant activity, ergosterol and fatty acids profile from huitlacoche produced in 15 creole and in one hybrid maize genotypes, and harvested at different stages of development were determined. The hybrid crop was studied in raw and cooked samples. Total phenolic content ranged from 415.6 to 921.8.0 mg gallic acid equivalents per 100 g of flour. Samples exhibited attractive antioxidant activities: 75 % of antiradical activity on average by DPPH methodology, and ORAC values up to 7661.3 µmol Trolox equivalents /100  g. Important quantities of ferulic acid, quercetin, ergosterol, linoleic and oleic acids were observed. Stage of development and cooking process had an effect on evaluated compounds, sometimes negative and sometimes positive. Results suggest that huitlacoche is an attractive food source of phenolics with excellent antioxidant potential and interesting lipidic compounds.

Healthy Ready-to-Eat Expanded Snack with High Nutritional and Antioxidant Value Produced from Whole Amarantin Transgenic Maize and Black Common Bean.

The snack foods market is currently demanding healthier products. A ready-to-eat expanded snack with high nutritional and antioxidant value was developed from a mixture (70:30) of whole amarantin transgenic maize (Zea mays L.) and black common bean (Phaseolus vulgaris L.) by optimizing the extrusion process. Extruder operation conditions were: feed moisture content (FMC, 15-25 %, wet basis), barrel temperature (BT, 120-170 °C), and screw speed (SS, 50-240). The desirability numeric method of the response surface methodology (RSM) was applied as the optimization technique over four response variables [expansion ratio (ER), bulk density (BD), hardness (H), antioxidant activity (AoxA)] to obtain maximum ER and AoxA, and minimum BD, and H values. The best combination of extrusion process variables for producing an optimized expanded snack (OES, healthy snack) were: FMC = 15 %/BT = 157 °C/SS = 238 rpm. The OES had ER = 2.86, BD = 0.119 g/cm (3) , H = 1.818 N, and AoxA = 13,681 µmol Trolox equivalent (TE)/100 g, dry weight. The extrusion conditions used to produce the OES increased the AoxA (ORAC: +18 %, ABTS:+20 %) respect to the unprocessed whole grains mixture. A 50 g portion of OES had higher protein content (7.23 vs 2.32 g), total dietary fiber (7.50 vs 1.97 g), total phenolic content (122 vs 47 mg GAE), and AoxA (6626 vs 763 µmol TE), and lower energy (169 vs 264 kcal) than an expanded commercial snack (ECS = Cheetos™). Because of its high content of quality protein, dietary fiber and phenolics, as well as high AoxA and low energy density, the OES could be used for health promotion and chronic disease prevention and as an alternative to the widely available commercial snacks with high caloric content and low nutritional/nutraceutical value.

Comparative Study of Phenolic Profile, Antioxidant Capacity, and Color-composition Relation of Roselle Cultivars with Contrasting Pigmentation.

Roselle is a plant that accumulates anthocyanins significantly, hence its importance as food coloring and as a source of antioxidant compounds for human health. This study was aimed to determine phenolic composition and antioxidant capacity of methanolic extracts, and beverages obtained from native roselle cultivars in Mexico (Negra, Sudan, Rosa and Blanca) with different degrees of pigmentation, and to establish the color-composition relationship. Chromatographic methods were used to determine phenolic compounds: flavanols, flavonols, benzoic, hibiscus and phenolic acids as well as two main anthocyanins (cyanidin 3-sambubioside and delphinidin 3-sambubioside). The antioxidant capacity was evaluated by ABTS and FRAP assays. Tristimulus colorimetry showed to be a useful technique to determine the color-composition relationship, leading to equations that allowed to predict anthocyanin content of roselle (R > 0.84). Also, a stepwise linear discriminant analysis (SLDA) was developed in order to classify roselle cultivars. The obtained mathematical model could be an important tool to be used in colorimetric characterization of functional compounds used in food processing.

Extracellular endoglucanase activity from Paenibacillus polymyxa BEb-40: production, optimization and enzymatic characterization.

Endoglucanase activity produced by Paenibacillus polymyxa BEb-40 was studied. In submerged culture with minimal medium supplemented with carboxymethylcellulose (CMC), this microorganism produced up to 0.37 U/mL endoglucanase activity with high specific activity (14.3 U/mgtotal protein). Detection of endoglucanase activity through zymography revealed at least 14 isoenzymes with molecular weights between 38 and 220 kDa. This high variety of secreted endoglucanases has not been described previously in Paenibacillus genus. The optimum conditions, determined by response surface methodology, were 48 °C and pH 3.4, which allowed an increase of 33.7 % in the relative endoglucanase activity obtained with respect to the standard conditions. Nevertheless, high levels of hydrolysis of at least 70 % of the maximum activity could be obtained at wide ranges of pH (2-9) and temperature (40-60 °C). Under optimal conditions, high levels of CMC hydrolysis were reached, of about 40 %, after only 12 h of reaction with substrate/total protein ratios between 19 and 76. Kinetic analysis revealed that endoglucanase activity followed a mixed inhibition model (K m = 8.4 mM, K ic = 0.03 mM, K iu = 0.35 mM, V max = 33.3 U/mgtotal protein). These results allow to consider P. polymyxa BEb-40 as a promising microorganism for the production of endoglucanases, with possibilities of application in the breakdown of lignocellulosic biomass. The high specific activity at wide ranges of pH and temperature can allow its use in a wide variety of processes, under both acidic and alkaline conditions, as well as in mesophilic and thermophilic temperatures, further reducing the amount of enzymes used.

Fruit quality: new insights for biotechnology.

At ripening fruits undergo many changes which include the development of color and aroma and improvements in flavor and texture that make them attractive to potential consumers. Fruits provide an important source of health-related substances, plus minerals and vitamins, and the quality of a fruit is influenced by variety, nutritional status, and environmental conditions during plant growth and fruit development. Ripening is considered to be the main process in fruit development, and all studies had been focused on this process which included physicochemical, biochemical, and molecular analysis. With the development of genomic analysis the strategies to study fruit ripening have been changing and now there are new perspectives and opportunities. The objective of this review is to describe the state of the art in the studies related to fruit ripening with emphasis in molecular studies.

Study of plastid genome stability in tobacco reveals that the loss of marker genes is more likely by gene conversion than by recombination between 34-bp loxP repeats.

In transformed tobacco (Nicotiana tabacum) plastids, we flank the marker genes with recombinase target sites to facilitate their posttransformation excision. The P1 phage loxP sites are identical 34-bp direct repeats, whereas the phiC31 phage attB/attP sites are 54- and 215-bp sequences with partial homology within the 54-bp region. Deletions in the plastid genome are known to occur by recombination between directly repeated sequences. Our objective was to test whether or not the marker genes may be lost by homologous recombination via the directly repeated target sites in the absence of site-specific recombinases. The sequence between the target sites was the bar(au) gene that causes a golden-yellow (aurea) leaf color, so that the loss of the bar(au) gene can be readily detected by the appearance of green sectors. We report here that transplastomes carrying the bar(au) gene marker between recombinase target sites are relatively stable because no green sectors were detected in approximately 36,000 seedlings (Nt-pSS33 lines) carrying attB/attP-flanked bar(au) gene and in approximately 38,000 seedlings (Nt-pSS42 lines) carrying loxP-flanked bar(au) gene. Exceptions were six uniformly green plants in the Nt-pSS42-7A progeny. Sequencing the region of plastid DNA that may derive from the vector indicated that the bar(au) gene in the six green plants was lost by gene conversion using wild-type plastid DNA as template rather than by deletion via directly repeated loxP sites. Thus, the recombinase target sites incorporated in the plastid genome for marker gene excisions are too short to mediate the loss of marker genes by homologous recombination at a measurable frequency.

Berries: improving human health and healthy aging, and promoting quality life--a review.

The importance of the diet in relation to human health has increased the interest of consumers on nutraceuticals rich foods, and especially on fruits and vegetables. Berries are rich sources of a wide variety of antioxidant phenolics; these phytochemicals include flavonoids, stilbenes, tannins, and phenolic acids. Reactive oxidant species and free radicals are produced in an extensive range of physiological processes. In addition to the antioxidant defenses produced in the body, there are exogenous sources supplied by the diet; this is the case of berry fruits, among others. The insufficiency of antioxidant defense mechanisms is associated to the pathology of chronic disorders such as cardiovascular diseases, inflammation, and diabetes. Therefore, the enforcement of the latter mechanisms is of the utmost importance. The isolation and characterization of compounds that may delay the onset of aging is receiving intense research attention; some berry phenolics are being associated with this functional performance. Berry phenolics may also act as antimicrobials which may be of help in the control of the wild spectra of pathogens, in view of recent problems associated with antibiotic resistance. Most of the research works on the antioxidant activity of bioactive constituents of berries has been carried out using in vitro assays. In view of this, the human studies investigating the bioavailability and potential toxicity of phenolics are receiving more attention. Finally, we would like to emphasize the necessity of associating new plant breeding and genetic studies of berries with the expression and overexpression of compounds for human health and healthy aging.

Next generation synthetic vectors for transformation of the plastid genome of higher plants.

Plastid transformation vectors are E. coli plasmids carrying a plastid marker gene for selection, adjacent cloning sites and flanking plastid DNA to target insertions in the plastid genome by homologous recombination. We report here on a family of next generation plastid vectors carrying synthetic DNA vector arms targeting insertions in the rbcL-accD intergenic region of the tobacco (Nicotiana tabacum) plastid genome. The pSS22 plasmid carries only synthetic vector arms from which the undesirable restriction sites have been removed by point mutations. The pSS24 vector carries a c-Myc tagged spectinomycin resistance (aadA) marker gene whereas in vector pSS30 aadA is flanked with loxP sequences for post-transformation marker excision. The synthetic vectors will enable direct manipulation of passenger genes in the transformation vector targeting insertions in the rbcL-accD intergenic region that contains many commonly used restriction sites.

Antioxidant activity of an unusual 3-hydroxyindole derivative isolated from fruits of Aristotelia chilensis (Molina) Stuntz.

3-Hydroxyindole was isolated from the EtOH extract of fruits of Aristotelia chilensis during analyses by HPLC/MS and GC/MS and identified by its mass fragmentation pattern and spectrophotometric data. Additionally, this extract showed an interesting antioxidant activity in DPPH, crocin and TBARS assays. The presence of this type of compound in this fruit species permits us to explain its strong antioxidant activity and its important part in the biosynthetic pathway of phenolic and alkaloid compounds in this plant. Therefore this compound could be useful for the development of future nutraceutical and antioxidant protective agents.

Physicochemical, nutritional and antibacterial characteristics of the fruit of Bromelia pinguin L.

Bromelia pinguin L. is a plant native to Sinaloa, Mexico, where its fruit is used as food or as a phytotherapeutic agent. The fruits of B. pinguin were characterized and they could be considered as a functional food. These fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, L* = 74.5). The values for acidity (4.6%, as citric acid) and pH (3.7) of B. pinguin fruit are similar to those of citrics. The edible portion is characterized by a high content of vitamin C (126 mg/100 g), ash (10.6 g/100 g d.w.), crude fiber (3.4 g/100 g d.w.), calcium (1290 mg/100 g d.w.), magnesium (500 mg/100 g d.w.), manganese (2.95 mg/100 g d.w.) and it is a good source of zinc (2.8 mg/100 g d.w.). Polar fractions extracted from the pulp fruit showed activity against several genera of human pathogenic-bacteria (Staphylococcus, Streptococcus, Enterococcus, Salmonella, Shigella, Escherichia and Pseudomonas).

Factors affecting genetic transformation by particle bombardment of the prickly pear cactus (O. ficus-indica).

In the present study, a novel transformation protocol for Opuntia ficus-indica was generated by means of particle bombardment. The best conditions obtained were: 900 psi rupture disk pressure, 8 cm microprojectile travel distance, and 4 h of exposition to 0.2 M mannitol. For all experiments, gold particles coated with 1.0 µg/µL of pBI426 plasmid DNA were used. With all these conditions, a 23% of transformation efficiency in terms of regeneration in selection media (100 mg/L kanamycin) was obtained. Interestingly, the presence of both transgenes: nptII and uidA, by means of PCR and RT-PCR assays was detected. The regeneration percentage achieved in terms of stable integration for both genes was 10%. In addition, we also detected adequate amounts of ß-glucuronidase activity by means of the GUS fluorometric assay. The procedure described in the present investigation reveals the feasibility of using nopal for the introduction, expression, and possible production of heterologous proteins.

Comparative transcriptome analysis of cultivated and wild seeds of Salvia hispanica (chia).

Salvia hispanica (chia) constituted an important crop for pre-Columbian civilizations and is considered a superfood for its rich content of essential fatty acids and proteins. In this study, we performed the first comprehensive comparative transcriptome analysis between seeds from cultivated varieties and from accessions collected from native wild populations in Mexico. From the 69,873 annotated transcripts assembled de novo, enriched functional categories and pathways revealed that the lipid metabolism was one of the most activated processes. Expression changes were detected among wild and cultivated groups and among growth conditions in transcripts responsible for triacylglycerol and fatty acid synthesis and degradation. We also quantified storage protein fractions that revealed variation concerning nutraceutical proteins such as albumin and glutelin. Genetic diversity estimated with 23,641 single nucleotide polymorphisms (SNPs) revealed that most of the variation remains in the wild populations, and that a wild-type cultivated variety is genetically related to wild accessions. Additionally, we reported 202 simple sequence repeat (SSRs) markers useful for population genetic studies. Overall, we provided transcript variation that can be used for breeding programs to further develop chia varieties with enhanced nutraceutical traits and tools to explore the genetic diversity and history of this rediscovered plant.

Nopal (Opuntia spp.) and its Effects on Metabolic Syndrome: New Insights for the Use of a Millenary Plant.

BACKGROUND: Nopal (Opuntia spp.) is by excellence the most utilized cactus in human and animal nutrition. It is also a very noble plant; its main physicochemical, nutritional and nutraceutical characteristics allow the use of nopal in diverse food applications. Special focus has been given over the past decades in the use of Opuntia for the treatment of metabolic syndrome (MetS), which is predominantly related to Diabetes Mellitus. In this sense, the prevalence of MetS is increasing at a worldwide level. This in turn has led to a notorious demand for natural and nutraceutical food sources. METHODS: The objective of this work was to summarize the main contributions in the field of Opuntia spp. research highlighting the potential use of nopal fruits or cladodes in MetS treatment, providing the reader with historical and novel information in this field. Nevertheless, the present work is not a meta-analysis. We included mainly information from recognized scientific databases, such as PubMed, Scopus, Web of Science and Google Scholar. No homeopathic based studies were included since they lack scientific validation. To the best of our knowledge, this is the first review that fairly categorizes the majority of the information in this field into subsections, which can be of interest for the reader, such as the effect of nopal against cardiovascular disease, type 2 diabetes mellitus, and obesity among others. CONCLUSION: Nopal constitutes one of the most studied members of the Cactaceae family; its potential effects on human health have been described since ancient times, mostly through traditional medicine. The present work highlights the importance of this plant in the treatment of MetS related maladies and points out the importance of elucidating new compounds and their validation for the interactions of nutraceutical compounds which could be related to MetS.