Pulque, a Traditional Mexican Alcoholic Fermented Beverage: Historical, Microbiological, and Technical Aspects

The complete genome of two Lactiplantibacillus plantarum isolates from the traditional Mexican fermented pulque beverage assembled with a combination of PacBio and Illumina platforms

We report the sequence of the complete genome and associated plasmids of two Lactiplantibacillus plantarum isolates from the traditional Mexican pulque beverage assembled with a combination of PacBio and Illumina data. The resulting complete genome for strain LB1_P46 is 3,287,706 bp; for strain LB2_P47, the complete genome is 3,289,072 bp.

Lessons from the history of Agave: ecological and cultural context for valuation of CAM

BACKGROUND AND SCOPE

Crassulacean acid metabolism (CAM) is an intriguing physiological adaptation in plants that are widespread throughout many ecosystems. Despite the relatively recent mechanistic understanding of CAM in plant physiology, evidence from historical records suggests that ancient cultures in the Americas also recognized the value of CAM plants. Agave species, in particular, have a rich cultural legacy that provides a foundation for commercially valued products. Here, we review that legacy and potential relationships between ancient values and the needs of modern-day climate adaptation strategies.

CONCLUSIONS

There are many products that can be produced from Agave species, including food, sugar, fibre and medicines. Traditional knowledge about agricultural management and preparation of plant products can be combined with new ecophysiological knowledge and agronomic techniques to develop these resources in the borderland region of the southwestern USA and Mexico. Historical records of pre-Columbian practices in the Sonoran desert and remnants of centuries-old agriculture in Baja California and Sonora demonstrate the climate resilience of Agave agriculture. Commercial growth of both tequila and bacanora indicates the potential for large-scale production today, but also underscores the importance of adopting regenerative agricultural practices to accomplish environmentally sustainable production. Recent international recognition of the Appellation of Origin for several Agave species produced for spirits in Mexico might provide opportunities for agricultural diversification. In contrast, fibre is currently produced from several Agave species on many continents. Projections of growth with future climate change suggest that Agave spp. will be viable alternatives for commodity crops that suffer declines during drought and increased temperatures. Historical cultivation of Agave affirms that these CAM plants can supply sugar, soft and hard fibres, medicines and food supplements.

Probiotic and functional potential of lactic acid bacteria isolated from pulque and evaluation of their safety for food applications

Pulque is a traditional Mexican non-distilled alcoholic beverage to which several beneficial functions are attributed, mainly associated with gastrointestinal health, which can be explained by the presence of probiotic bacteria in its microbiota. Therefore, the objective of this work was to evaluate the safety, probiotic activity, and functional characteristics of seven strains of lactic acid bacteria (LAB) isolated from pulque using the probiotic strain Lactobacillus acidophilus NCFM as control. The LAB isolates were identified by 16S rRNA sequencing and MALDI Biotyper® MS as belonging to three different Lactobacillaceae genera and species: Lactiplantibacillus plantarum, Levilactobacillus brevis and Lacticaseibacillus paracasei. Most strains showed resistance to gastric juice, intestinal juice and lysozyme (10 mg/L). In addition, all strains exhibited bile salt hydrolase (BSH) activity and antibacterial activity against the pathogenic strain Listeria monocytogenes. Additionally, cell surface characteristics of LAB were evaluated, with most strains showing good hydrophobicity, auto-aggregation, and co-aggregation towards enteropathogenic Escherichia coli and L. monocytogenes. In terms of safety, most of the strains were sensitive to the tested antibiotics and only the Lact. paracasei UTMB4 strain amplified a gene related to antibiotic resistance (mecA). The strains Lact. plantarum RVG2 and Lact. plantarum UTMB1 presented γ-hemolytic activity, and the presence of the virulence-related gene agg was identified only in UTMB1 strain. Regarding functional characterization, the tested bacteria showed good β-galactosidase activity, antioxidant activity and cholesterol reduction Based on principal component analysis (PCA) and heat mapping, and considering the strain Lact. acidophilus NCFM as the probiotic reference, the strains Lacticaseibacillus paracasei UTMB4, Lactiplantibacillus plantarum RVG4 and Levilactobacillus brevis UTMB2 were selected as the most promising probiotic strains. The results of this study highlighted the probiotic, functional and safety traits of LAB strains isolated from pulque thus supporting the health benefits attributed to this ancestral beverage.

Genotypic and Phenotypic Diversity of Kluyveromyces marxianus Isolates Obtained from the Elaboration Process of Two Traditional Mexican Alcoholic Beverages Derived from Agave: Pulque and Henequen (Agave fourcroydes) Mezcal

Seven Kluyveromyces marxianus isolates from the elaboration process of pulque and henequen mezcal were characterized. The isolates were identified based on the sequences of the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacer (ITS-5.8S) region. Genetic differences were found between pulque and henequen mezcal isolates and within henequen mezcal isolates, as shown by different branching patterns in the ITS-5.8S phylogenetic tree and (GTG)5 microsatellite profiles, suggesting that the substrate and process selective conditions may give rise to different K. marxianus populations. All the isolates fermented and assimilated inulin and lactose and some henequen isolates could also assimilate xylose and cellobiose. Henequen isolates were more thermotolerant than pulque ones, which, in contrast, presented more tolerance to the cell wall-disturbing agent calcofluor white (CFW), suggesting that they had different cell wall structures. Additionally, depending on their origin, the isolates presented different maximum specific growth rate (µmax) patterns at different temperatures. Concerning tolerance to stress factors relevant for lignocellulosic hydrolysates fermentation, their tolerance limits were lower at 42 than 30 °C, except for glucose and furfural. Pulque isolates were less tolerant to ethanol, NaCl, and Cd. Finally, all the isolates could produce ethanol by simultaneous saccharification and fermentation (SSF) of a corncob hydrolysate under laboratory conditions at 42 °C.

Analysis of the Microbial Diversity and Population Dynamics during the Pulque Fermentation Process

Pulque is the most-studied traditional Mexican alcoholic beverage prepared by fermentation of the fresh sap (aguamiel, AM) extracted from different Agave species (maguey) cultivated for pulque production. This beverage has been produced mainly in the Central Mexico Plateau since pre-Columbian times. In this contribution, we report the analysis of the bacterial and fungal diversity through 16S rRNA gene V3–V4 fragment amplicon and ITSR1 sequencing associated with the tissue of the walls (metzal) of the cavity or cajete, where the sap accumulates in producing plants for its daily extraction, in AM, and during four fermentation stages for pulque production. The results led to determining which microorganisms detected in the plant tissue are present in AM and maintained during the fermentation process. The results showed that eight bacterial OTUs (Lactobacillus, Leuconostoc, Weisella, Lactococcus, Acetobacter, Gluconobacter, Zymomonas, and Obesumbacterium) and five fungal OTUs (Kazachstania, Kluyveromyces, Saccharomyces, Hanseniaspora, and the OTU O_Saccharomycetales) were present from metzal to AM and during all the stages of the fermentation analyzed. The detected diversity was considered the microbial core for pulque fermentation, comprising up to ~84% of the total bacterial diversity and up to ~99.6% of the fungal diversity detected in the pulque produced from three plants of A. salmiana from the locality of Huitzilac, Morelos, Mexico. This study provides relevant information on the potential microorganisms responsible for pulque fermentation, demonstrating that the core of microorganisms is preserved throughout the elaboration process and their association with the AM and fermented beverage physiochemical profile.

Disappearance and survival of fermented beverages in the biosphere reserve Tehuacán-Cuicatlán, Mexico: The cases of Tolonche and Lapo

Traditional fermented products are disappearing from the local foodscapes due to social pressures and ecological changes that affect their production; it is therefore crucial to document local knowledge, which is crucial to maintain and recover local biocultural heritage and to contribute to food security. This study aims to document and foster the production of local traditional beverages by registering recipes of fermented beverages in the Tehuacán-Cuicatlán biosphere reserve in central Mexico, a region recognized for its great biocultural diversity. We conducted a search of peer-reviewed literature. Additionally, we included ethnographic research and participatory methods to engage residents in different steps of the production process. We identified five main fermented beverages in the research area, the most common beverages are those produced by agave species which include, mescal, pulque and an almost extinct beverage known as lapo which involves sugar cane as main substrate. We also identified a fermented beverage produced with several cacti fruits known as nochoctli and a traditional a fermented beverage produced with fruits of Schinus molle known as tolonche. We highlight the production of lapo and tolonche since these involved the incorporation of foreign substrates into the region after the Spaniard conquest and to their restricted distribution and almost extinction. The beverages tolonche and lapo are nowadays almost lost and only a few producers still prepare them to follow modified versions of the original recipe. Lapo and tolonche were once important in the research area but almost became extinct until local people started to recently recover them. Traditional fermented beverages in Mexico play an important role in cultural identity and contribute to the local diet; nevertheless, several fermented beverages have not been recorded and have even become extinct. This work is an effort to promote and conserve traditional fermented beverages as valuable biocultural heritage by empowering people to make decisions about the use of locally available resources, which is crucial in times when food systems are highly vulnerable.

Microencapsulation of steroidal saponins from agave sap concentrate using different carriers in spray drying

Concentrated agave sap is a product with in vivo proven hypocholesterolemic and hypoglycemic activities, as well as in vitro anticancer potential. In the present work, a factorial design was used to determine the suitable drying conditions of concentrated agave by studying the effect of inlet temperature (150 °C, 180 °C and 210 °C) and the type of carrier agent (maltodextrin, hydroxypropyl methylcellulose, guar gum and xanthan gum). The response variables for each treatment were the product recovery and microencapsulated saponins. Further characterization of concentrated agave powders was performed: solubility in water, hygroscopicity, moisture content, tap density, bulk density, Carr's index followability and morphology by scanning electron microscopy analysis. The hydroxypropyl methylcellulose proved to improve physicochemical properties and enhance product yield, using 210 °C inlet temperature and a mix of carrier agents of maltodextrin/hydroxypropyl methylcellulose/xanthan gum at 50/48.5/1.5 (w/w/w) proportion exhibited the highest saponin recovery of 53.81%. Moreover, different carrier agents in powders revealed two shapes, regular spherical shape with smooth surface and collapsed shapes. The use of polymers excipients helped to decrease the stickiness of the desired product and enhanced the powder stability and microencapsulation of the steroidal saponins.

Biotechnological and Medical Aspects of Lactic Acid Bacteria Used for Plant Protection: A Comprehensive Review

The use of chemical pesticides in agriculture goes hand in hand with some crucial problems. These problems include environmental deterioration and human health complications. To eliminate the problems accompanying chemical pesticides, biological alternatives should be considered. These developments spark interest in many environmental fields, including agriculture. In this review, antifungal compounds produced by lactic acid bacteria (LABs) are considered. It summarizes the worldwide distribution of pesticides and the effect of pesticides on human health and goes into detail about LAB species, their growth, fermentation, and their antifungal compounds. Additionally, interactions between LABs with mycotoxins and plants are discussed.

Traditional Fermented Foods and Beverages from around the World and Their Health Benefits

Traditional fermented foods and beverages play an important role in a range of human diets, and several experimental studies have shown their potential positive effects on human health. Studies from different continents have revealed strong associations between the microorganisms present in certain fermented foods (e.g., agave fructans, kefir, yeats, kombucha, chungkookjang, cheeses and vegetables, among others) and weight maintenance, reductions in the risk of cardiovascular disease, antidiabetic and constipation benefits, improvement of glucose and lipids levels, stimulation of the immunological system, anticarcinogenic effects and, most importantly, reduced mortality. Accordingly, the aim of this review is to corroborate information reported in experimental studies that comprised interventions involving the consumption of traditional fermented foods or beverages and their association with human health. This work focuses on studies that used fermented food from 2014 to the present. In conclusion, traditional fermented foods or beverages could be important in the promotion of human health. Further studies are needed to understand the mechanisms involved in inflammatory, immune, chronic and gastrointestinal diseases and the roles of fermented traditional foods and beverages in terms of preventing or managing those diseases.

Constructing Micro-Landscapes: Management and Selection Practices on Microbial Communities in a Traditional Fermented Beverage

Colonche is a traditional beverage produced in Mexico by the fermentation of fruits of several cacti species. In the Meridional Central Plateau region of Mexico, where this study was conducted, it is mainly produced with fruits of Opuntia streptacantha; there, the producers perform spontaneous fermentation and/or fermentations through inoculums. Several factors can change the microbial community structure and dynamics through the fermentation process, but little attention has been directed to evaluate what type and extent of change the human practices have over the microbial communities. This study aims to assess the microbiota under spontaneous and inoculated fermentation techniques, the microorganisms present in the inoculums and containers, and the changes of microbiota during the process of producing colonche with different techniques. We used next-generation sequencing of the V3-V4 regions of the 16S rRNA gene and the ITS2, to characterize bacterial and fungal diversity associated with the different fermentation techniques. We identified 701 bacterial and 203 fungal amplicon sequence variants (ASVs) belonging to 173 bacterial and 187 fungal genera. The alpha and beta diversity analysis confirmed that both types of fermentation practices displayed differences in richness, diversity, and community structure. Richness of bacteria in spontaneous fermentation (0D = 136 ± 0.433) was higher than in the inoculated samples (0D = 128 ± 0.929), while fungal richness in the inoculated samples (0D = 32 ± 0.539) was higher than in spontaneous samples (0D = 19 ± 0.917). We identified bacterial groups like Lactobacillus, Leuconostoc, Pediococcus and the Saccharomyces yeast shared in ferments managed with different practices; these organisms are commonly related to the quality of the fermentation process. We identified that clay pots, where spontaneous fermentation is carried out, have an outstanding diversity of fungal and bacterial richness involved in fermentation, being valuable reservoirs of microorganisms for future fermentations. The inoculums displayed the lowest richness and diversity of bacterial and fungal communities suggesting unconscious selection on specific microbial consortia. The beta diversity analysis identified an overlap in microbial communities for both types of fermentation practices, which might reflect a shared composition of microorganisms occurring in the Opuntia streptacantha substrate. The variation in the spontaneous bacterial community is consistent with alpha diversity data, while fungal communities showed less differences among treatments, probably due to the high abundance and dominance of Saccharomyces. This information illustrates how traditional management guides selection and may drive changes in the microbial consortia to produce unique fermented beverages through specific fermentation practices. Although further studies are needed to analyze more specifically the advantages of each fermentation type over the quality of the product, our current analysis supports the role of traditional knowledge driving it and the relevance of plans for its conservation.

Probiotic activity traits in vitro and production of antimicrobial peptides by Lactobacillaceae isolates from pulque using Lactobacillus acidophilus NCFM as control

The objective of this work was to determine in vitro probiotic activity traits of 11 lactic acid bacteria (LAB) strains isolated from pulque obtained from three different locations in the Mexican states of Oaxaca and Puebla using the probiotic strain Lactobacillus acidophilus NCFM as a positive control, and to detect their production of antimicrobial peptides, including bacteriocins and peptidoglycan hydrolases (PGH). The LAB isolates were identified by sequencing of their 16S rRNA as belonging to four different genera of the Lactobacillaceae family: Lactiplantibacillus, Levilactobacillus, Lacticaseibacillus and Liquorilactobacillus, corresponding to the species plantarum, brevis, paracasei and ghanensis, respectively. Most of the strains showed resistance to high acidity (pH 2) and bile salts (0.5%), with survival rates up to 87 and 92%, respectively. In addition, most of the strains presented good antimicrobial activity against the foodborne pathogens Listeria monocytogenes, ECEC and Salmonella Typhi. The strain Liquorilactobacillus ghanensis RVG6, newly reported in pulque, presented an outstanding overall performance on the probiotic activity tests. In terms of their probiotic activity traits assessed in this work, the strains compared positively with the control L. acidophilus NCFM, which is a very-well documented probiotic strain. For the antimicrobial peptide studies, four strains presented bacteriocin-like mediated antibiosis and six had significant PGH activity, with two strains presenting outstanding overall antimicrobial peptide production: Lacticaseibacillus paracasei RVG3 and Levilactobacillus brevis UTMB2. The probiotic performance of the isolates was mainly dependent on strain specificity. The results obtained in this work can foster the revalorization of pulque as a functional natural product.

Consumer's acceptability and health consciousness of probiotic and prebiotic of non-dairy products

Human gut microbiota is a protective agent of intestinal and systemic health, and its modulation is of great interest for human wellbeing. In the world of biotics, besides probiotics, prebiotics, and synbiotics, also appears the denomination of "postbiotics" and "psychobiotics". Fermented dairy products are, traditionally, the major source of probiotics. Nevertheless, due to the increasing number of lactose-intolerant individuals and strict vegetarians, there is a need for innovative non-dairy products. Non-dairy biotics are being included in the normal diet and due to technological advances, many products are created using non-conventional food matrices like kombucha tea, herbal tea, baking mix, and cereal-based products. The microorganisms most used as probiotics in many of the non-dairy products are strains belonging to the genera Bifidobacterium, Enterococcus, Lactobacillus, Lactococcus, Streptococcus, and Bacillus, and some yeast strains namely Saccharomyces cerevisiae var. boulardii. Recently, several other yeasts have been described as having probiotic properties. This review describes gut-derived effects in humans of possible microorganisms, such as yeasts, and bacteria, isolated from non-dairy fermented and non-fermented foods and beverages. The microorganisms responsible for the processing of these non-dairy fermented products, together with the prebiotics, form a class of nutrients that have been proven to be beneficial for our gut health.

From Past to Present: Biotechnology in Mexico Using Algae and Fungi

Algae and fungi share a rich history in the fields of basic and applied natural science. In biotechnology, in particular, algae and fungi are of paramount importance, due to the production and development of valuable compounds, such as pharmaceuticals, enzymes, and biofuels. They are also used in waste fermentation, biocontrol of pathogens, and food processing and improvement, among other fields. Although a substantial number of different microorganisms are utilized for these purposes, there lies tremendous potential in uncharacterized microbial species. For this reason, biodiversity hotspots offer a wealth of potential in the discovery of new products and processing strategies based on these microorganisms. This review presents an overview of the use of algae and fungi in pre-Hispanic times/modern-day Mexico for the benefits of mankind. One of our objectives is to raise awareness about the potential of developing research projects for identification and biotechnological utilization of algae and fungi in a megadiverse country, such as Mexico.

Building an Ethnic Food Ethic: The Case of the Ngigua Indigenous People of Southern Puebla, Mexico

Food ethics in the indigenous context is associated with a historical and profound relationship that indigenous groups have with nature. To address this relationship and identify the food uses associated with the maguey plant from a biocultural perspective among the Ngigua indigenous people living in the municipality of Tlacotepec de Benito Juárez in Puebla, the three main communities in the municipality of Tlacotepec de Benito Juárez that make use of the maguey plant were chosen. The study was carried out with a qualitative approach, using a semi-structured interview as a research technique. The analysis carried out recognises the importance of the maguey plant as a biocultural resource for the Ngigua in a context of ethical deliberation. Among the food uses associated with the maguey plant, the following are identified: pulque (a drink of pre-Hispanic origin) and red worm. Women play an important role, participating in 80% of the preparation of both foods. The cultural environment of the maguey is a way of life that, in the case of the Ngigua people, represents a strategic element for survival. In times of food crisis, the study shows how ethnic food strategies in a context of ethical deliberation can constitute an alternative for the design of food solutions in territories with food shortages.

Traditional Fermented Beverages of Mexico: A Biocultural Unseen Foodscape

Mexico is one of the main regions of the world where the domestication of numerous edible plant species originated. Its cuisine is considered an Intangible Cultural Heritage of Humanity and ferments are important components but have been poorly studied. Traditional fermented foods are still diverse, but some are endangered, requiring actions to promote their preservation. Our study aimed to (1) systematize information on the diversity and cultural history of traditional Mexican fermented beverages (TMFB), (2) document their spatial distribution, and (3) identify the main research trends and topics needed for their conservation and recovery. We reviewed information and constructed a database with biocultural information about TMFB prepared and consumed in Mexico, and we analyzed the information through network approaches and mapped it. We identified 16 TMFB and 143 plant species involved in their production, species of Cactaceae, Asparagaceae, and Poaceae being the most common substrates. Microbiological research has been directed to the potential biotechnological applications of Lactobacillus, Bacillus, and Saccharomyces. We identified a major gap of research on uncommon beverages and poor attention on the cultural and technological aspects. TMFB are dynamic and heterogenous foodscapes that are valuable biocultural reservoirs. Policies should include their promotion for conservation. The main needs of research and policies are discussed.

Research opportunities: Traditional fermented beverages in Mexico. Cultural, microbiological, chemical, and functional aspects

In Mexico, close to 200 fermented products have been described, of which, approximately 20 are beverages. They were obtained through rustic and ancestral fermentation methods by different indigenous Mexican communities; most of them were used in ceremonies, agricultural work, and other occasions. For their elaboration, different substrates obtained from plants are used, where uncontrolled and low-scale spontaneous anaerobic fermentation occurs. In Mexico, some of these products are considered as nutritional sources and functional beverages; the study of those products has revealed the presence of multiple compounds of biological importance. Additionally, elder generations attribute healing properties against diverse illnesses to these beverages. The aim of this review is to highlight the available information on twelve traditional Mexican fermented beverages, their traditional uses, and their fermentation processes along with toxicological, chemical, nutritional, and functional studies as seen from different areas of investigation. In the literature, pulque, cocoa, and pozol were the beverages with the greatest amount of described health properties; sendechó and guarapo were less characterized. Polyphenols, gallic and ferulic acid, anthocyanins and saponins were the most abundant molecules in all beverages. Finally, it is important to continue this research in order to determine the microorganisms that are involved in the fermentation process, as well as the organoleptic and beneficial properties they lend to the traditional Mexican fermented beverages.

Microbial interactions in alcoholic beverages

This review examines the different types of interactions between the microorganisms involved in the fermentation processes of alcoholic beverages produced all over the world from cereals or fruit juices. The alcoholic fermentation converting sugars into ethanol is usually carried out by yeasts, mainly Saccharomyces cerevisiae, which can grow directly using fruit sugars, such as those in grapes for wine or apples for cider, or on previously hydrolyzed starch of cereals, such as for beers. Some of these beverages, or the worts obtained from cereals, can be distilled to obtain spirits. Besides S. cerevisiae, all alcoholic beverages can contain other microorganisms and especially in spontaneous fermentation when starter cultures are not used. These other microbes are mostly lactic acid bacteria and other yeasts-the non-Saccharomyces yeasts. The interactions between all these microorganisms are very diverse and complex, as in any natural occurring ecosystem, including food fermentations. To describe them, we have followed a simplified ecological classification of the interactions. The negative ones are amensalism, by which a metabolic product of one species has a negative effect on others, and antagonism, by which one microbe competes directly with others. The positive interactions are commensalism, by which one species has benefits but no apparent effect on others, and synergism, by which there are benefits for all the microbes and also for the final product. The main interactions in alcoholic beverages are between S. cerevisiae and non-Saccharomyces and between yeasts and lactic acid bacteria. These interactions can be related to metabolites produced by fermentation such as ethanol, or to secondary metabolites such as proteinaceous toxins, or are feed-related, either by competition for nutrients or by benefit from released compounds during yeast autolysis. The positive or negative effects of these interactions on the organoleptic qualities of the final product are also revised. Focusing mainly on the alcoholic beverages produced by spontaneous fermentations, this paper reviews the interactions between the different yeasts and lactic acid bacteria in wine, cider, beer, and in spirits such as tequila, mezcal and cachaça.

Sustainable Production of Pulque and Maguey in Mexico: Current Situation and Perspectives

Pulque is a traditional Mexican fermented, non-distilled alcoholic beverage produced by fermenting the fresh sap (aguamiel) extracted from several Agave (maguey) species cultivated for pulque production (mainly A. salmiana). This beverage was produced and consumed since Pre-Hispanic times by Mesoamerican civilizations, mainly in the Mexican Central Plateau, and is one of the essential alcoholic beverages produced and consumed during several centuries in Mexico. By 2019, annual pulque production was reported in 171,482 billion liters. Nevertheless, traditional pulque production faces several significant limitations, including the disappearance of large agave plantations and the extent of time required (at least 5 years) to complete the plant maturation for aguamiel extraction; traditional production practices; and the lack of an efficient stabilization process of the fermented product resulting in low shelf life. In opposition, successful examples of sustainable cultivation of maguey species for aguamiel extraction and the fermentation process's industrialization resulted in high-quality pulque production, with international exportation certification. In this contribution, we present a review of the most relevant aspects of the history and commercial relevance of pulque, the causes that resulted in its production debacle during the first half of the twentieth century, the current situation of its traditional production, and the successful efforts of industrial production of the beverage. We describe recent results on the analysis of the physicochemical characteristics of aguamiel and on the microbiology of the beverage explored by metagenomic techniques that can be proposed as a baseline to redefine the quality criteria of the beverage and to define for the first time a microbiological core to optimize its production. We describe the relevance of maguey species for aguamiel production as a fundamental element of agroforestry and the relevance of its sustainable production, in four sustainable plantation models to maintain a stable plant population to ensure the continuous extraction of aguamiel and pulque production. Finally, we describe some successful examples of beverage industrialization and potential applications of several microorganisms isolated from aguamiel, pulque, aguamiel concentrates, and the maguey to produce high-value bioactive products.

Effect of the Intake of a Traditional Mexican Beverage Fermented with Lactic Acid Bacteria on Academic Stress in Medical Students

Dysbiosis of the gut microbiota has been associated with different illnesses and emotional disorders such as stress. Traditional fermented foods that are rich in probiotics suggest modulation of dysbiosis, which protects against stress-induced disorders. The academic stress was evaluated in medical students using the SISCO Inventory of Academic Stress before and after ingestion of an aguamiel-based beverage fermented with Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus brevis (n = 27) and a control group (n = 18). In addition, microbial phyla in feces were quantified by qPCR. The results showed that the consumption of 100 mL of a beverage fermented with lactic acid bacteria (3 × 10⁸ cfu/mL) for 8 weeks significantly reduced academic stress (p = 0.001), while the control group (placebo intervention) had no significant changes in the perception of academic stress (p = 0.607). Significant change (p = 0.001) was shown in the scores for environmental demands, and physical and psychological factors. Consumption of the fermented beverage significantly increased the phyla Firmicutes and Bacteroidetes but not Gammaproteobacteria. No significant changes were found in the control group, except for a slight increase in the phylum Firmicutes. The intake of this fermented beverage suggest a modulation of gut microbiota and possible reduction in stress-related symptoms in university students, without changing their lifestyle or diet.

Genome and Pangenome Analysis of Lactobacillus hilgardii FLUB-A New Strain Isolated from Mead

The production of mead holds great value for the Polish liquor industry, which is why the bacterium that spoils mead has become an object of concern and scientific interest. This article describes, for the first time, Lactobacillus hilgardii FLUB newly isolated from mead, as a mead spoilage bacteria. Whole genome sequencing of L. hilgardii FLUB revealed a 3 Mbp chromosome and five plasmids, which is the largest reported genome of this species. An extensive phylogenetic analysis and digital DNA-DNA hybridization confirmed the membership of the strain in the L. hilgardii species. The genome of L. hilgardii FLUB encodes 3043 genes, 2871 of which are protein coding sequences, 79 code for RNA, and 93 are pseudogenes. L. hilgardii FLUB possesses three clustered regularly interspaced short palindromic repeats (CRISPR), eight genomic islands (44,155 bp to 6345 bp), and three (two intact and one incomplete) prophage regions. For the first time, the characteristics of the genome of this species were described and a pangenomic analysis was performed. The concept of the pangenome was used not only to establish the genetic repertoire of this species, but primarily to highlight the unique characteristics of L. hilgardii FLUB. The core of the genome of L. hilgardii is centered around genes related to the storage and processing of genetic information, as well as to carbohydrate and amino acid metabolism. Strains with such a genetic constitution can effectively adapt to environmental changes. L. hilgardii FLUB is distinguished by an extensive cluster of metabolic genes, arsenic detoxification genes, and unique surface layer proteins. Variants of MRS broth with ethanol (10-20%), glucose (2-25%), and fructose (2-24%) were prepared to test the strain's growth preferences using Bioscreen C and the PYTHON script. L. hilgardii FLUB was found to be more resistant than a reference strain to high concentrations of alcohol (18%) and sugars (25%). It exhibited greater preference for fructose than glucose, which suggests it has a fructophilic nature. Comparative genomic analysis supported by experimental research imitating the conditions of alcoholic beverages confirmed the niche specialization of L. hilgardii FLUB to the mead environment.

Thermosonication as an alternative method for processing, extending the shelf life, and conserving the quality of pulque: A non-dairy Mexican fermented beverage

The aim of this study was to evaluate thermosonication as an alternative method for the pasteurization of pulque in order to improve its shelf life and retain its quality parameters. Thermosonication was carried out at 50 °C using amplitudes of 75% (for 6 and for 9 min), 85% (for 4 and for 6 min), and 95% (for 3 and for 5 min). These were the optimal conditions found for processing pulque by thermosonication. Physicochemical (acidity, color, alcohol content, and sensory analysis) and microbiological (lactic acid bacteria and yeasts) parameters were determined during 30 days for storage at 4 ± 1 °C. Conventional pasteurization (63 °C, 30 min) and raw pulque were used as controls. According to the results, the shelf life of pulque was extended up to 24 days storage at 4 °C. After this time, the quality of beverage decreased, due that the microbial load increases. Thermosonication treatments at 75% and 85% showed a higher content of LAB (6.58-6.77 log CFU/mL) and yeasts (7.08-7.27 log CFU/mL) than conventional pasteurization (3.64 log CFU/mL of LAB and 3.97 log CFU/mL of yeasts) at 24 days of storage. Raw pulque demonstrated up to 7.77 log CFU/mL of yeasts and 7.51 log CFU/mL of LAB. Pulque processed by thermosonication exhibited greater lightness, sensory acceptance, a maximal acidity of 0.83 g/lactic acid, and an alcohol content of 4.48-4.95% v/v. The thermosonication process preserves sensory and physicochemical properties better than conventional pasteurization. Lactic acid bacteria such as Lactobacillus kefiri, Lactobacillus acidophilus, and Lactobacillus hilgardii and yeasts such as Saccharomyces cereviasiae were identified in thermosonicated pulque.

Production Performance, Nutrient Digestibility, and Milk Composition of Dairy Ewes Supplemented with Crushed Sunflower Seeds and Sunflower Seed Silage in Corn Silage-Based Diets

Simple Summary

In countries such as Mexico and the Unites States, sunflowers can be planted earlier than corn, and can tolerate moderate frosts. Concerning sunflower silage, its feeding value could be up to 80% similar to that of corn silage. The use of sunflower silage for ruminant feeding represents an alternative to the use of corn silage, especially when environmental conditions are adverse for corn crops. Sunflower seeds can also be a protein alternative to soybean by-products. This study determined production performance, nutrient digestibility, and milk composition of dairy ewes fed with crushed sunflower seeds (SF) and sunflower seed silage (SFS) in corn silage-based diets. Compared to control, SF and SFS increased intake and digestibility of fiber components, such as neutral detergent fiber (NDF) and acid detergent fiber (ADF). Nitrogen balance, milk yield, milk fat yield, and milk protein yield were similar between treatments. Results demonstrated that crushed sunflower seeds and ensiled seeds do not change significantly productive parameters of dairy sheep. In corn-silage based diets, both crushed and ensiled sunflower seeds can be used in dairy sheep diets as alternatives to typical protein feedstuffs, such as soybean meal.

Abstract

This study determined production performance, nutrient digestibility, and milk composition of dairy ewes supplemented with crushed sunflower seeds (Helianthus annuus) and sunflower seed silage in corn silage-based diets. Six ewes were grouped in a double 3 × 3 Latin square design with three periods of 21 days. All treatments were based on ad libitum corn silage. Control diet was based on alfalfa hay (333 g/kg DM), sorghum grain (253 g/kg DM), triticale grain (200 g/kg DM), soybean meal (167 g /kg DM), and vitamin and mineral premix (47 g/kg DM). Sunflower seeds (SF) and sunflower seed silage (SFS) treatments consisted of alfalfa hay (333 g/kg DM), sorghum grain (267 g/kg DM), triticale grain (100 g/kg DM), soybean meal (167 g /kg DM), SF or SFS (87 g/kg DM) and vitamin and mineral premix (47 g/kg DM). Compared to control, SF and SFS increased intake and digestibility of fiber components, such as neutral detergent fiber (NDF) and acid detergent fiber (ADF). Body weight, nitrogen balance, milk yield, milk fat yield, milk protein yield, lactose yield and milk urea N were similar between treatments. Overall, results demonstrated that crushed sunflower seeds and ensiled seeds do not change significantly productive parameters of dairy sheep.

Agave: a natural renewable resource with multiple applications

Agaves are a group of succulent plants that thrive in arid or semiarid environments. Indeed, genes associated with their resilience are a potential resource for genetic engineering of other agronomically important crops grown in adverse climates. Agave is mainly used for the production of distilled (spirits) and non-distilled alcoholic beverages, including tequila, mezcal, bacanora, raicilla, and pulque, all of which have special connections to Mexican history and culture, and contribute to the Mexican economy. In recent years, there has been growing interest to maximize the use of agave plant materials for other purposes, as the bulk of their biomass pre- and post-production is wasted. In traditional practice, during the passage from fields to factories, only agave cores are used, and the leaves and bagasse are not always harnessed. To place this in perspective, during the period from 2010 to 2019, 2674.7 × 10⁶  L of tequila was produced in Mexico, which required 9 607 400 tons of agave cores. This generated approximately the same amount of leaves and 3 842 960 tons of bagasse. The economic base of agave plants can be expanded if expended biomass could be transformed into products that are useful for applications in food, forage, ensilage, agriculture, medicine, energy, environment, textiles, cosmetics, and esthetics. This review focuses on the current utility of agave plants, as well as our perspective for future studies and uses of this formidable plant. © 2020 Society of Chemical Industry.

Evolution of Fructans in Aguamiel (Agave Sap) During the Plant Production Lifetime

Aguamiel is the sap collected from agave, while pulque is the result of the natural fermentation of aguamiel. Despite its ancestral origin and numerous publications on pulque production, little is known about the evolution and concentration of sugars and fructo-oligosaccharides in aguamiel, either during its daily accumulation or through the agave production lifetime. In this study, we examined aguamiel composition in three agave plants during their productive lifetime (4 to 9 months). After each collection, the agave pine is scraped to induce aguamiel to flow into an internally created cavity (cajete), producing a residual bagasse (metzal). We found that the concentration of agave fructans and sucrose, as well as the fructan profile, change during the aguamiel production process. During the daily collection, a small amount of agave fructans released from the pine by scraping is drawn into the cajete with the first milliliters of sap where it is then diluted with the inflow of aguamiel. The main component of aguamiel is the sucrose produced in high concentration in the leaves through photosynthesis and then hydrolyzed in the cajete as aguamiel accumulates. We also describe how the fructan profile changes during the accumulation of aguamiel in the cajete. In addition to the varying amount of sucrose that is hydrolyzed in the aguamiel accumulated, we found that fructo-oligosaccharides are either diluted, consumed, or hydrolyzed, depending on the plant and its production stage, thus yielding different fructan profiles. New fructo-oligosaccharides are, in some cases, synthesized by bacteria present in aguamiel. These profiles were also observed in aguamiel collected from ten different plants in the same production region. We also found that a considerable amount of agave fructans is lost in metzal (bagasse), the agave material that is scraped and thrown away twice a day during the production process.

Microbial Fermentation and Its Role in Quality Improvement of Fermented Foods

Fermentation processes in foods often lead to changes in nutritional and biochemical quality relative to the starting ingredients. Fermented foods comprise very complex ecosystems consisting of enzymes from raw ingredients that interact with the fermenting microorganisms’ metabolic activities. Fermenting microorganisms provide a unique approach towards food stability via physical and biochemical changes in fermented foods. These fermented foods can benefit consumers compared to simple foods in terms of antioxidants, production of peptides, organoleptic and probiotic properties, and antimicrobial activity. It also helps in the levels of anti-nutrients and toxins level. The quality and quantity of microbial communities in fermented foods vary based on the manufacturing process and storage conditions/durability. This review contributes to current research on biochemical changes during the fermentation of foods. The focus will be on the changes in the biochemical compounds that determine the characteristics of final fermented food products from original food resources.

Assessment of the bacterial diversity of agave sap concentrate, resistance to in vitro gastrointestinal conditions and short-chain fatty acids production

Low bacterial diversity in the gut has been associated with the development of several diseases. Agave sap concentrate (ASC) is obtained from the thermal treatment of the fresh sap called "aguamiel", an artisanal Mexican food. In this study, we assessed the microbial diversity from three different ASC producing regions in Mexico using high-throughput sequencing of the 16S rRNA gene and evaluated their resistance to an in vitro gastrointestinal process as well as their ability to produce short-chain fatty acids (SCFA). Seven phyla and 120 genera were detected in ASC samples; Firmicutes had the highest relative read abundance at the phylum level, whereas Bacillus was the most abundant genus. Bacterial diversity at phylum and genus levels was highly dependent on the region where ASC was produced. The microbiota from a selected sample was resistant to low pH conditions, bile salts and intestinal enzymes. Moreover, bacteria were able to survive and grow in the colonic environment. SCFA production was comparable with that observed for a well-known probiotic, Lactobacillus plantarum 299v, that was used as control. These findings demonstrate that ASC contains a bacterial ecosystem with potential probiotic benefits.

Genomic profiling of bacterial and fungal communities and their predictive functionality during pulque fermentation by whole-genome shotgun sequencing

Pulque is a culturally important 4,000-year-old traditional Mexican fermented drink. Pulque is produced by adding fresh aguamiel (agave sap) to mature pulque, resulting in a mixture of microbial communities and chemical compositions. We performed shotgun metagenomic sequencing of five stages of pulque fermentation to characterize organismal and functional diversity. We identified 6 genera (Acinetobacter, Lactobacillus, Lactococcus, Leuconostoc, Saccharomyces and Zymomonas) and 10 species (Acinetobacter boissieri, Acinetobacter nectaris, Lactobacillus sanfranciscensis, Lactococcus lactis, Lactococcus piscium, Lactococcus plantarum, Leuconostoc citreum, Leuconostoc gelidum, Zymomonas mobilis and Saccharomyces cerevisiae) that were present ≥ 1% in at least one stage of pulque fermentation. The abundance of genera and species changed during fermentation and was associated with a decrease in sucrose and increases in ethanol and lactic acid, suggesting that resource competition shapes organismal diversity. We also predicted functional profiles, based on organismal gene content, for each fermentation stage and identified an abundance of genes associated with the biosynthesis of folate, an essential B-vitamin. Additionally, we investigated the evolutionary relationships of S. cerevisiae and Z. mobilis, two of the major microbial species found in pulque. For S. cerevisiae, we used a metagenomics assembly approach to identify S. cerevisiae scaffolds from pulque, and performed phylogenetic analysis of these sequences along with a collection of 158 S. cerevisiae strains. This analysis suggests that S. cerevisiae from pulque is most closely related to Asian strains isolated from sake and bioethanol. Lastly, we isolated and sequenced the whole-genomes of three strains of Z. mobilis from pulque and compared their relationship to seven previously sequenced isolates. Our results suggest pulque strains may represent a distinct lineage of Z. mobilis.

Traditional fermented beverages in Mexico: Biotechnological, nutritional, and functional approaches

Preservation of food through fermentation is an ancient practice that, besides extending produce shelf-life, has represented a significant source of nutrients and health-promoting compounds in the human diet throughout history. Traditional fermented beverages are an essential element of the cultural and culinary heritage of many countries. In Mexico, several indigenous fermented beverages have been consumed since prehispanic times, and are still used for ceremonial purposes. The production of these beverages is generally from fruits, plants, maize, and maize dough, which are utilized as a substrate by microorganisms during spontaneous fermentation. This review compiles information from the most relevant studies concerning Mexican fermented beverages. These have generally focused on three principal aspects: (1) the identification and isolation of the endogenous microorganisms involved in the fermentation process, including the addition of specific molds, yeasts, and bacteria under controlled conditions aiming to standardize the fermentation process, (2) an exploration of the functionality of the microorganisms and the subproducts generated during their metabolic process, and (3) an analysis of the nutritional value of the fermented beverages. Hence, this review aims at contributing to the dissemination of biotechnological knowledge of Mexican fermented beverages, towards the identification and advancement of alternative research pathways.

Spontaneously fermented traditional beverages as a source of bioactive compounds: an overview

Fermented food has been present throughout history, since fermentation not only helps preserving food, but also provides specific organoleptic characteristics typically associated to these foods. Most of the traditional fermented foods and artisanal beverages are produced by spontaneous generation, meaning no control of the microbiota, or the substrate used. Nevertheless, even not being standardized, they are an important source of bioactive compounds, such as antioxidant compounds, bioactive beeps, short chain fatty acids, amino acids, vitamins, and minerals. This review compiles a list of relevant traditional fermented beverages around the world, aiming to detail the fermentation process itself-including source of microorganisms, substrates, produced metabolites and the operational conditions involved. As well as to list the bioactive compounds present in each fermented food, together with their impact in the human health. Traditional fermented beverages from Mexico will be highlighted. These compounds are of high interest for the food, pharmaceutical and cosmetics industry. To scale-up the home fermentation processes, it is necessary to fully understand the microbiology and biochemistry behind these traditional products. The use of good quality raw materials with standardized methodologies and defined microorganisms, may improve and increase the production of the desirable bioactive compounds and open a market for novel functional products.

Identifying consumers’ profile and factors associated with the valorization of pulque: A traditional fermented beverage in Central Mexico

The aims of this work were to (i) identify the consumers’ profile of pulque through their consumption frequency and their sensory perception of this beverage and (ii) identify the factors that contribute to the valorization of pulque among Mexican consumers. A survey was designed and conducted with 221 consumers in pulque-selling locations (pulquerías) in a place of Central Mexico. Consumers were characterized according to their consumption frequency. Factors associated with the valorization of pulque were identified through Binary Logistic Regression model. Two types of consumers were identified: Frequent Consumers and Not Frequent Consumers. Both groups were comprised mostly of men, including students with medium to high levels of education. However, the first group showed more traditional and conservative behavior patterns since there was a higher proportion of consumers with a low educational level ( p < 0.05) and they had more years of consumption, spend more time in the selling locations, and preferred “natural pulque.” The second group of consumers was comprised mostly ( p < 0.05) of women, including students with a high educational level who prefer “cured pulque.” In this sense, our results showed that gender and time spent in the pulquerías together with sensory, cultural, and functional characteristics associated with the beverage influence its valorization among consumers. These results can help both producers and marketers to classify segments of consumers according to their preferences and consumption patterns in order to revalorize the pulque market. Finally, it is necessary to highlight that young consumers with high educational level show interest in this beverage, since for years its consumption has been associated with low-income populations.

Physical, Chemical, and Microbiological Characteristics of Pulque: Management of a Fermented Beverage in Michoacán, Mexico

Pulque is a beverage that has been prepared in Mexico since pre-Hispanic times from the fermented sap of more than 30 species of wild and domesticated agaves. We conducted studies in two communities of the state of Michoacán, in central-western Mexico, where we documented its traditional preparation and analyzed the relationship between preparation conditions and the composition and dynamics of microbiological communities, as well as the physical and chemical characteristics of the beverage. In one of the communities, Santiago Undameo (SU), people boil the sap before inoculating it with pulque inoculum; this action causes this local pulque to be sweeter, less acidic, and poorer in bacteria and yeast diversity than in the other community, Tarimbaro (T), where the agave sap is not boiled and where the pulque has more diversity of microorganisms than in SU. Fermentation management, particularly boiling of the agave sap, influences the dynamics and diversity of microbial communities in the beverage.

Management, morphological and genetic diversity of domesticated agaves in Michoacán, México

BACKGROUND

Pulque is a fermented beverage prepared with sap of Agave species in Mexico. Management of agaves for this purpose has motivated domestication of some species and high phenotypic variation that commonly causes uncertainty about the taxonomic identity of varieties traditionally managed by people. This study assumed that varieties of crop species continually arise from mutations, sexual reproduction and hybridization, among other processes, and some of them are favoured and maintained by humans. Identifying these varieties may be difficult and a challenging issue for botanists and evolutionary biologists studying processes of domestication. Through a case study, we analysed the traditional varieties of agaves used to produce pulque in Michoacán, Mexico. We aimed at identifying the varieties, analysing the relatedness among them and developing a methodological approach that could help solve taxonomic problems and study variation under domestication of this and other plant groups. We documented (1) the traditional varieties of agave used and their identity, (2) how these varieties are perceived, used and managed by the local people and (3) how management influences phenotypic and genetic variation among varieties.

METHODS

We interviewed pulque producers in two localities of the state of Michoacán, Mexico, where we recorded management practices of agaves, the traditional varieties used, the attributes characterizing those varieties, the varieties preferred by people, and features and mechanisms of selection. We conducted multivariate analyses of morphological features of the agave varieties, as well as genetic diversity and genetic distance studies among agave varieties through 11 nuclear microsatellites.

RESULTS

Seven traditional varieties of Agave were recorded in the study area. Multivariate analyses of morphology identified varieties belonging to the species A. salmiana, A. mapisaga and, presumably, A. americana. The preferred varieties have morphological features selected to make easier their management and produce higher sap yields. Genetic diversities (HE = 0. 470 to 0.594) were high compared with other Agave species with similar life history traits and use. Genetic distance analyses grouped the varieties "Verde" and "Negro" (identified as A. salmiana), whereas the varieties "Tarímbaro" and "Listoncillo" (identified as A. mapisaga) formed another group. The varieties "Blanco" and "Carrizaleño" (most probably being A. americana) clustered with varieties of A. salmiana, whereas the variety "Cenizo" appeared as a distinct group. Bayesian analysis indicated that most individuals of varieties of A. salmiana form a group and those of the varieties of A. mapisaga form another, whereas individuals of the varieties putatively belonging to A. americana clustered in similar proportions with both groups.

CONCLUSIONS

The traditional pulque production in the study area is an ongoing practice. It is still an important source of products for direct consumption by households and generation of economic incomes and as part of the cultural identity of local people. The most used traditional variety exhibited a marked gigantism, and although these agaves are mainly asexually propagated, populations have high genetic diversity. The local producers promote the maintenance of different traditional varieties. Our study shows the value of an integral research approach including ethnobiological, morphological and genetic information to clarify the state of variation influenced by humans on agaves, but it would be helpful to study other organisms under domestication. In addition, such approach would help to document human and non-human mechanisms generating crop varieties managed by local people.

Undervalued potential of crassulacean acid metabolism for current and future agricultural production

The potential for crassulacean acid metabolism (CAM) to support resilient crops that meet demands for food, fiber, fuel, and pharmaceutical products far exceeds current production levels. This review provides background on five families of plants that express CAM, including examples of many species within these families that have potential agricultural uses. We summarize traditional uses, current developments, management practices, environmental tolerance ranges, and economic values of CAM species with potential commercial applications. The primary benefit of CAM in agriculture is high water use efficiency that allows for reliable crop yields even in drought conditions. Agave species, for example, grow in arid conditions and have been exploited for agricultural products in North and South America for centuries. Yet, there has been very little investment in agricultural improvement for most useful Agave varieties. Other CAM species that are already traded globally include Ananas comosus (pineapple), Aloe spp., Vanilla spp., and Opuntia spp., but there are far more with agronomic uses that are less well known and not yet developed commercially. Recent advances in technology and genomic resources provide tools to understand and realize the tremendous potential for using CAM crops to produce climate-resilient agricultural commodities in the future.

Influence of fermentation by different microflora consortia on pulque and pulque bread properties

BACKGROUND

Pulque bread is a traditional Mexican product obtained by fermentation using microflora present only in pulque. In this study, the possibility of creating a pulque microbial consortium under laboratory conditions and its applications were evaluated. A laboratory-made consortium was compared with a consortium originating in Mexico in bread and pulque production. They were tested in various growth medium systems: pulque made from agave sap and malt extract, Mexican wheat and rye pulque bread, and European wheat and rye bread.

RESULTS

Depending on the growth medium, consortiums showed differing influence on many factors, such as specific volume, weight loss after baking, soluble proteins, and crust and crumb color. Indigenous starters increased sensorial acceptance of pulque and Mexican rye bread, decreased pH, and increased titratable acidity of the breads at the highest level whereas laboratory consortia improved sensory acceptance of wheat breads. The laboratory-prepared starter in some cases improved antiradical activity. All pulques received similar consumer evaluations. However, malt pulque was the least appreciated beverage.

CONCLUSION

The results show the possibility of creating a pulque microbial consortium under laboratory conditions. Depending on the flour type and the breadmaking technique, the use of a particular microbial consortium allowed modification of certain physicochemical parameters. In conclusion, it is feasible to modify bread parameters to obtain features corresponding to consumer demands by using an appropriate microflora, pulque, or flour type. Moreover, this research describes, for the first time, the use of rye malt for pulque and rye flour for pulque bread preparation as raw materials. © 2019 Society of Chemical Industry.

Enzymatic Process Yielding a Diversity of Inulin-Type Microbial Fructooligosaccharides

The specificity of fructooligosaccharides as prebiotics depends on their size and structure, which in turn depend on their origin or the synthesis procedure. In this work we describe the application of an inulosucrase (IslA) from Leuconostoc citreum CW28 to produce high molecular weight inulin from sucrose alongside a commercial endoinulinase (Novozym 960) produced by Aspergillus niger for a simultaneous or sequential reaction to synthesize fructooligosaccharides (FOS). The simultaneous reaction resulted in a higher substrate conversion and a wide diversity of FOS when compared to the sequential reaction. A shotgun MS analysis of the commercial endoinulinase preparation surprisingly revealed an additional enzymatic activity: a fructosyltransferase, responsible for the synthesis of FOS from sucrose. Consequentially, the range of FOS obtained in reactions combining inulosucrase from Ln. citreum with the fructosyltransferase and endoinulinase from A. niger with sucrose as substrate may be extended and regulated.

Microbiome-MX 2018: microbiota and microbiome opportunities in Mexico, a megadiverse country

A weekly conference series paired with lectures entitled "Microbiome-MX: exploring the Microbiota and Microbiome Research in Mexico" was organized to provide a multidisciplinary overview of the most recent research done in Mexico using high-throughput sequencing. Scientists and postgraduate students from several disciplines such as microbiology, bioinformatics, virology, immunology, nutrition, and medical genomics gathered to discuss state of the art in each of their respective subjects of expertise, as well as advances, applications and new opportunities on microbiota/microbiome research. In particular, high-throughput sequencing is a crucial tool to understand the challenges of a megadiverse developing country as Mexico, and moreover to know the scientific capital and capabilities available for collaboration. The conference series addressed three main topics important for Mexico: i) the complex role of microbiota in health and prevalent diseases such as obesity, diabetes, inflammatory bowel disease, tuberculosis, HIV, autoimmune diseases and gastric cancer; ii) the use of local, traditional and prehispanic products as pre/probiotics to modulate the microbiota and improve human health; and iii) the impact of the microbiota in shaping the biodiversity of economically important terrestrial and marine ecosystems. Herein, we summarize the contributions that Mexican microbiota/microbiome research is making to the global trends, describing the highlights of the conferences and lectures, rather than a review of the state-of-the-art of this research. This meeting report also presents the efforts of a multidisciplinary group of scientist to encourage collaborations and bringing this research field closer for younger generations.

Bacterial Diversity and Population Dynamics During the Fermentation of Palm Wine From Guerrero Mexico

Palm wine is obtained by fermentation of palm tree sap. In the Pacific coast of Mexico, palm wine is called Tuba and it is consumed as a traditional fermented beverage. Tuba has empirical applications such as an auxiliary in gastrointestinal diseases and a good source of nutrients. In the present study, a next-generation sequencing of the V3-V4 regions of the 16S rRNA gene was employed to analyze bacterial diversity and population dynamics during the fermentation process of Tuba, both in laboratory controlled conditions and in commercial samples from local vendors. Taxonomic identification showed that Fructobacillus was the main genus in all the samples, following by Leuconostoc, Gluconacetobacter, Sphingomonas, and Vibrio. Alpha diversity analysis demonstrated variability between all the samples. Beta diversity clustered the bacterial population according to the collection origin of the sample. Metabolic functional profile inference showed that the members of the bacterial communities may present the vitamin, antibiotic and antioxidant biosynthesis genes. Additionally, we further investigated the correlation between the predominant genera and some composition parameters of this beverage. This study provides the basis of the bacterial community composition and functionality of the fermented beverage.

Bioprospecting for brewers: Exploiting natural diversity for naturally diverse beers

The burgeoning interest in archaic, traditional, and novel beer styles has coincided with a growing appreciation of the role of yeasts in determining beer character as well as a better understanding of the ecology and biogeography of yeasts. Multiple studies in recent years have highlighted the potential of wild Saccharomyces and non-Saccharomyces yeasts for production of beers with novel flavour profiles and other desirable properties. Yeasts isolated from spontaneously fermented beers as well as from other food systems (wine, bread, and kombucha) have shown promise for brewing application, and there is evidence that such cross-system transfers have occurred naturally in the past. We review here the available literature pertaining to the use of nonconventional yeasts in brewing, with a focus on the origins of these yeasts, including methods of isolation. Practical aspects of utilizing nondomesticated yeasts are discussed, and modern methods to facilitate discovery of yeasts with brewing potential are highlighted.

Saccharomyces cerevisiae populations and other yeasts associated with indigenous beers (chicha) of Ecuador

Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.