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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. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-022-00684-7.

The objective of this work was to evaluate the effectiveness of the putative biocontrol agents (PBA) Bacillus paralicheniformis and Trichoderma asperelloides in vitro and in vivo to control two of the most important tomato plant diseases: vascular wilt (Fusarium oxysporum) and early blight (Alternaria alternata). The assessment of the in vitro interactions between the PBA and the phytopathogenic fungi was performed by dual confrontation assays. The biocontrol effectiveness of the individual and combined PBA treatments towards individual phytopathogen inoculations was evaluated in tomato plants. T. asperelloides was able to exert an outstanding mycoparasitic effect on both phytopathogenic fungi in the in vitro tests by hyphal strangulation and penetration. In addition, the individual PBA treatments were effective in the biocontrol of A. alternata and F. oxysporum in tomato plants reducing the plant disease severity in more than 53.8 and 66.7% for each of the pathogens, respectively. On the other hand, the combined use of the tested strains showed similar effectiveness in the biocontrol of A. alternata, but no synergism was observed. In addition, it was concluded that B. paralicheniformis protected the plants from the attack of A. alternata through the induction of the systemic resistance of the plant. This study demonstrated the effectiveness of the individual and combined use of the strains tested for the biocontrol of A. alternata and F. oxysporum in tomato plants.

Resumen Antecedentes La caracterizacion molecular de cepas silvestres de Pleurotus es importante para la conservacion del germoplasma y su posterior uso en la mejora genetica. No se han realizado estudios moleculares con los monocariontes utilizados para la produccion de cepas hibridas, ni de las cepas reconstituidas obtenidas al aparear tales monocariontes. Por consiguiente, la caracterizacion molecular de cepas dicarioticas parentales, hibridas y reconstituidas, asi como de cepas monocarioticas, es de suma importancia. Objetivos Caracterizar molecularmente cepas dicarioticas silvestres e hibridas, asi como cepas monocarioticas de Pleurotus djamor. Metodos Se recolectaron cinco cepas silvestres de P. djamor en diferentes estados de Mexico y se identificaron molecularmente mediante la secuenciacion de la region ITS1-5.8-ITS2 con los oligonucleotidos universales ITS1 e ITS4. Se seleccionaron dos cepas silvestres y se generaron cuatro cepas hibridas por apareamiento de neohaplontes compatibles. Para la caracterizacion molecular de las cepas monocarioticas y dicarioticas seleccionadas y producidas se utilizaron seis marcadores ISSR. Resultados Con los marcadores ITS se obtuvo un producto de amplificacion de 700 pb en las cinco cepas silvestres con una similitud del 99-100% con la especie P. djamor. Con los marcadores ISSR se obtuvieron un total de 95 fragmentos con un 99% de polimorfismo. Conclusiones Las cepas silvestres se identificaron como P. djamor. Los marcadores ISSR generaron bandas polimorficas en las cepas monocarioticas y dicarioticas, y separaron ambos tipos de cepas. El alto grado de polimorfismo indica la diversidad genetica de P. djamor, una ventaja para la produccion de hongos y para la mejora de la especie.

Huauzontle (Chenopodium berlandieri subsp. Nuttalliae) is a species native to Mexico. Over the centuries, important nutritional and medical properties have been attributed to this species in ancient Mexican tradition. In contrast, quinoa (Chenopodium quinoaWilld.), an Andean crop genetically related to huauzontle, has been widely studied and acknowledged for its outstanding potential as a high quality protein source. Considering this, the main objective of this study was to obtain and purify the protein fractions of huauzontle seeds using alkaline extraction, isoelectric precipitation, and ultrafiltration membrane technology. Different pH settings were tested for the extraction and precipitation operations and pH 11 and 3.5 were selected, respectively. The protein mass balance for both extraction and precipitation, accounted for 96.6% and 98.7% of the proteins respectively. Using a 10 kDa ultrafiltration membrane, the protein was concentrated and purified by ultrafiltration and diafiltration at 45-50 °C with a concentration factor of 4 and a diafiltration volume of 4. A precipitated protein isolate was obtained with 78.96% purity. In this study, a process that combines alkaline extraction, isoelectric precipitation and ultrafiltration membrane technology was successfully employed to separate and purify huauzontle protein fractions to a level comparable to those reported in the literature for other proteinaceous seeds. In addition, this work will help to establish huauzontle, an ancient native Mexican crop, as an important source of protein, which can also be used as a protein supplement for staple foods.

The genus Pleurotus is the third most commonly produced edible fungi in the world. In addition, species of genus Pleurotus have functional properties such as anticancer, antiviral, antimicrobial, anti-inflammatory, and antioxidant activities, which are mainly attributed to phenolic compounds. For these reasons, this study evaluated the productivity and antioxidant activity (AA) of 2 wild strains (white and pink), 2 reconstituted strains (called "BB" and "RR"), and 4 hybrid strains (H1, H2, H3, and H4) of P. djamor from monokaryotic components (neohaplonts). The results showed that the white wild-type strain and the reconstituted strains exhibited the best production potential, expressed as biological efficiency and mycelial growth rate. The carpophores of hybrid strains H1 and H3 had the greatest AA, as evaluated with DPPH radical scavenging and reducing power assays, respectively. The H3 strain had the highest total phenol (TP) content. Pearson correlations led us to conclude that the mycelial growth rate has a regular inverse correlation with TP and a regular direct correlation with AA of methanolic extracts from carpophores and myce-lia. This is, to our knowledge, the first report in the literature about the effect of Pleurotus strain hybridization through a chemical de-dikaryotization process on TP content.

The food industry is becoming more specialized and processing methods are continuously being developed to meet consumer needs. Consumers demand products that are safe and preferably free of synthetic additives. These additives are associated with health effects, in most cases without reasonable justification. Consequently, consumers are looking for clearly labelled products that guarantee the absence of synthetic additives. This has led to the need to search for natural additives, which the food industry claims arenatural antioxidant preservatives. The sources of natural antioxidants can be extremely varied, because practically all plants contain antioxidants that allow them to protect themselves from solar radiation and pests, as well as to regulate the production of chemical energy. However, the best alternatives for the food industry are fruits and spices, because they are already foods themselves. This article will describe fruits and spices considered as important sources of phenolic antioxidants. The main medicinal properties are related to phenolic compounds and their uses as additives, depending on their chemical structure.

Molecular characterisation of wild type Pleurotus species is important for germplasm conservation and its further use for genetic improvement. No molecular studies have been performed with monokaryons used for producing hybrid strains, either with the reconstituted strains obtained by pairing those monokaryons. The molecular characterisation of parental dikaryons, hybrid, and reconstituted strains as well as monokaryotic strains, is therefore of utmost importance.To carry out the molecular identification of Pleurotus djamor strains, i.e. dikaryotic wild type strains, hybrid strains, and the monokaryotic strains used for the hybrid formation.Five wild type strains of P. djamor from different states in Mexico were collected and molecularly identified by sequencing the ITS1-5.8-ITS2 region using ITS1 and ITS4 universal oligonucleotides. Four hybrid strains were obtained by pairing neohaplonts of two wild type strains selected. Six ISSR markers were used for the molecular characterisation of monokaryotic and dikaryotic strains.Using the ITS markers, an amplified product of 700bp was obtained in five wild type strains, with a 99-100% similarity with P. djamor. A total of 95 fragments were obtained using the ISSR markers, with 99% of polymorphism.Wild type strains were identified as P. djamor, and were clearly grouped with Mexican strains from other states of Mexico. ISSR markers allowed the generation of polymorphic bands in monokaryotic and dikaryotic strains, splitting both types of strains. The high degree of polymorphism indicates the genetic diversity of P. djamor, an advantage in mushroom production and in the improving of the species.

Despite microalgae recently receiving enormous attention as a potential source of biodiesel, their use is still not feasible as an alternative to fossil fuels. Recently, interest in microalgae has focused on the production of bioactive compounds such as polyunsaturated fatty acids (PUFA), which provide microalgae a high added value. Several considerations need to be assessed for optimizing PUFA production from microalgae. Firstly, a microalgae species that produces high PUFA concentrations should be selected, such as Nannochloropsis gaditana, Isochrysis galbana, Phaeodactylum tricornutum, and Crypthecodinium cohnii, with marine species gaining more attention than do freshwater species. Closed cultivation processes, e.g., photobioreactors, are the most appropriate since temperature, pH, and nutrients can be controlled. An airlift column with LEDs or optical fibers to distribute photons into the culture media can be used at small scale to produce inoculum, while tubular and flat panels are used at commercial scale. Depending on the microalgae, a temperature range from 15 to 28 °C and a pH from 7 to 8 can be employed. Relevant conditions for PUFA production are medium light irradiances (50-300 μmol photons m(-2) s(-1)), air enriched with (0-1 % (v/v) CO2, as well as nitrogen and phosphorous limitation. For research purposes, the most appropriate medium for PUFA production is Bold's Basal, whereas mixotrophic cultivation using sucrose or glucose as the carbon source has been reported for industrial processes. For cell harvesting, the use of tangential flow membrane filtration or disk stack centrifugation is advisable at commercial scale. Current researches on PUFA extraction have focused on the use of organic solvents assisted with ultrasound or microwaves, supercritical fluids, and electroporation or are enzyme assisted. Commercial-scale extraction involves mainly physical methods such as bead mills and expeller presses. All these factors should be taken into account when choosing a PUFA production system, as discussed in this review.

El huauzontle (Chenopodium berlandieri subsp. nuttalliae) es una especie mexicana a la cual se le atribuyen importantes propiedades nutrimentales de manera tradicional. Asimismo, considerando que el huauzontle comparte una estrecha relación genética con una fuente de proteína vegetal de alta calidad, la quinoa; es probable que el huauzontle comparta estos atributos nutricionales. El objetivo de este estudio fue encontrar las condiciones ideales para el aislamiento de la proteína de semilla de huauzontle empleando técnicas de extracción alcalina, ultrafiltración y diafiltración con membranas, así como caracterizar las proteínas por su contenido de aminoácidos vía HPLC y las fracciones proteicas por electroforesis SDS-PAGE. Se compararon dos diferentes pesos moleculares de corte de la membrana (5 y 10 kDa) y del proceso se obtuvieron dos principales productos: el aislado de proteína precipitada (APP) y el aislado de proteína soluble (APS). El proceso de purificación de proteína con la membrana de 5 kDa tuvo mejores rendimientos y purezas proteicas. Se observó que con el uso de la membrana de 5 kDa se obtuvo un APP con una pureza cercana al 70%, así como una recuperación total de la proteína superior al 90%, mostrando de esta manera la alta eficiencia del proceso. Por otro lado, la proteína de huauzontle resultó con 5 aminoácidos esenciales con contenidos superiores a los niveles de ingesta recomendados por la FAO, destacando el alto contenido de lisina y metionina. Asimismo, en las fracciones proteicas se encontró la presencia de proteínas con pesos moleculares similares a las globulinas 7s y 11s, características del género Chenopodium. Se puede concluir que el uso de las técnicas de extracción alcalina y precipitación isoeléctrica acopladas a la tecnología de ultrafiltración constituyen un proceso adecuado para el aislamiento y la purificación de las proteínas de la semilla de huauzontle. Los resultados de este proyecto pueden contribuir a la revalorización del huauzontle como una fuente alimenticia de alta calidad proteica para la población vulnerable y a despertar el interés científico por el increíble potencial nutricional que tiene esta especie endémica mexicana.

Pleurotus spp. (seta) es un hongo comestible que ocupa el tercer lugar en producción a nivel mundial. En nuestro equipo de trabajo se aislaron previamente cepas silvestres de P. djamor (UTMB y UTMR), obteniendo nuevas cepas reconstituidas (BB y RR) e híbridas (H1, H2, H3 y H4) a partir de componentes monocarióticos. La presente investigación evaluó la productividad y la actividad antioxidante (AA) de extractos metanólicos de carpóforos y micelios de las cepas antes mencionadas. La cepa silvestre UTMR y las cepas reconstituidas fueron las que presentaron mejor potencial productivo. Los carpóforos de las cepas híbridas presentaron mejor AA. H3 tuvo un IC50 = 3.26 ± 0.03 mg/mL, en el ensayo de reducción del radical DPPH y H1 un IC50 = 3.52 ± 0.05 mg/mL con el método de Poder Reductor (PR). Mientras que los micelios de las cepas híbridas presentaron mejor contenido de fenoles totales (FT), H3 tuvo 1.77 ± 0.03 mg EAG/g ms. Se concluyó que la velocidad de crecimiento micelial no tuvo relación con la productividad de las cepas y que la AA de los extractos metanólicos de carpóforos y micelio no se relacionó con los flavonoides.