Isolation of a Leuconostoc mesenteroides ssp. jonggajibkimchii strain from Parona leatherjacket (Parona signata): behavior in vegetal matrices fermentation

A Gram-positive, facultatively anaerobic, gas-forming, catalase-negative, nonmotile, non-sporeforming, vancomycin-resistant, and ovoid-shaped bacterium, designated strain Tw234, was isolated from the intestinal tract of Parona leatherjacket (Parona signata). The strain grew in the presence of 0–6% (w/v) NaCl, at pH 3.5–8.5 and 8–40 °C; optimum growth was achieved at 1% (w/v) NaCl, at pH 6.0 and 30–32 °C. Exopolysacharides production was detected by the solidification test of skim milk supplemented with sucrose in the temperature range of 8 to 30 °C. Results of phylogenetic analysis based on the 16S rRNA gene sequence similarity indicated that strain Tw234 was closed related to the genus Leuconostoc and 100% homology with the type strain Ln. mesenteroides ssp. jonggajibkimchii DRC1506 (KCCM 43249, JCM 31787). The evaluation of growth and acidification rates were carried out in white cabbage and Chinese cabbage and compared with the strain Ln. mesenteroides ssp. jonggajibkimchii RCTw1.1, isolated from the spontaneous fermentation of red cabbage. No significant differences were observed between the behaviors of the two strains. The strain Tw234 displayed higher growth and acidification rates in controlled fermentation of white cabbage compared with those obtained in Chinese cabbage. New trends are targeted on the isolation and selection of strains to achieve controlled fermentation of vegetables that may ensure uniform quality. The results obtained in this work suggest that strain Tw234 harbored technological useful properties for its potential use as a starter in controlled vegetable fermentations.

Arbuscular mycorrhiza symbiosis in quinoa (Chenopodium quinoa Willd.): A systematic review

The crop of quinoa has gained relevance during the last decade in different parts of the world, due to its adaptability to difficult edaphic and climatic conditions and the great nutritional potential of its seeds. However, climate change scenarios are increasingly adverse, so the search for strategies that favor greater adaptability of quinoa to areas where other crops fail to adapt is a scientific priority. For this reason, a systematic review was carried out, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis methodology, with documents published on Scopus and Clarivate Web of Science databases. This methodology describes the diversity of fungi that favors symbiosis and the services offered by arbuscular mycorrhizal fungi in the physiological activity of the quinoa plant, in addition to their interaction with the edaphic conditions, mainly related to nitrogen and phosphorus. The results identified a projection of interest in research related to the symbiosis between these two organisms, but a very limited advance in relation to the study that has been developed around the microbiological activity of quinoa in the soil.

Antifungal effect from Zingiber officinale, Aloe vera and Trichoderma sp. for control of Moniliophthora roreri in Theobroma cacao in Huánuco, Peru

Theobroma cacao is the main raw material to produce chocolate, as well as for use in the food, cosmetic, and pharmaceutical industries. However, Moniliophthora roreri is one of the most destructive fungal diseases and the main limiting of cacao production worldwide. Thus, this work aimed to assess the inhibitory effect of extracts of Zingiber officinale (T1) and Aloe vera (T2), and Trichoderma harzianum + Bacillus subtillis. (T3) on Moniliophthora roreri infection in Theobroma cacao; in addition, a control (T4) was also evaluated. Each treatment was applied to six plants of cacao. Incidence of monilia infection and fruit weight were monitored every 15 days (in total four periods) after the application of the treatment by spray. Significant differences (P<0.05) were found among treatments for incidence. It was observed that spraying entire cacao trees after two times (approximately 30 days) showed a reduction of monilia infection. After all periods, T1, T2, and T3 showed an incidence of monilia infection by 20.5, 17.7, and 14.9% respectively, compared to cultural control of 41.1%. This reduction of moniliasis infection translates into an increase in fruit weight average for T3 (8.4 kg), T2 (7.3 kg), and T1 (6.9 kg). In contrast, in the control (T3), the fruit weight average decreased by 5.3 kg. Biological control showed efficient management of pathogens as M. roreri. It is recommended to use such antifungal (Aloe vera) spray over at least 120 days which would decrease infection incidence even more.

Assessing the influence of cereal-legume mixtures on the productivity of degraded pastures in the Kostanay region of northern Kazakhstan

This study presents the results of some options to restore pastures with low productivity in the arid steppes of the Kostanay region of northern Kazakhstan, describing the effects associated with grass-legume mixtures. The effects of grass-legume mixtures, contribution to the preservation and maintenance of pasture forage crops, and the productivity of pastures were discussed. Mixtures of grasses and legumes were selected that are promising crops for arid regions.The plant density and its condition were determined based on test plots of adjacent rows of 0.5 m each, followed by counting. The plant height was determined before the yield of green mass by measuring 25 plants of each species. The yield of green mass in the maturity phase of the grass was determined by mowing and weighing the green mass in the plots, followed by the analysis of the species composition in the grass mixture and drying until air dry. The density of plants, the height of the plants, and the safety of the forage plants according to the sowing method were the data collected. In addition, the effect of grass mixtures on the productivity of forage crops to improve pastures was compared. According to these results, the highest productivity under experimental conditions was found in the wheat grassalfalfa-bromegrass variant. This information can contribute to the improvement of the state of the pastures since it is complete and inexpensive food for farm animals.

Commercial meat cuts hardness of dual-purpose cattle from Cundinamarca (Colombia) high tropics zone

Este estudio tuvo como objetivo determinar el efecto del biotipo, la edad al sacrificio, la condición sexual y el sistema de alimentación sobre la dureza de cuatro cortes comerciales: Lomo (Longissimus dorsi), Bota (Biceps femoris), Muchacho (Semitendinosus) y Paletero (Infraspinatus), provenientes de 50 bovinos pertenecientes a sistemas de doble propósito del trópico alto en el departamento de Cundinamarca, Colombia. Para la obtención de los valores en este atributo se emplearon los métodos de medición instrumental de fuerza de corte con cuchilla de Warner-Bratzler y la evaluación sensorial, cuya correlación fue del 71%. Esto permitió la elaboración de una escala de dureza en la cual los cortes Lomo y Paletero se ubicaron en la categoría de “suave” (blando) y se comportaron estadísticamente igual en ambos métodos de medición, mientras que los cortes Bota y Muchacho se ubicaron en la categoría de “medio” y tuvieron diferencias estadísticas de acuerdo con la percepción dada por el panel sensorial. Así mismo, los resultados obtenidos mostraron diferencias significativas entre los cortes, destacando al Paletero por su menor valor de dureza y comportamiento similar al Lomo. Efectos significativos sobre la dureza de la carne fueron encontrados para todos los factores a excepción de la edad, lo cual muestra la influencia que tienen estos y su manejo en finca sobre la calidad de la carne.

Selecting optimal parameters for obtaining the extract of red grape pomace

Due to the industrial processing of grapes, large amounts of by-products are produced. The main varieties of by-products are pomace, which is comprised of skins, seeds and any other solid remaining after pressing process and sediments. It is necessary to implement new effective ways of processing to minimize these residues. This problem is relevant for all the wine-producing countries, including Georgia. It is well-known fact that pomace is an important source of phenolic compounds, which are characterized by high antioxidant activity and possess healing-prophylactic properties. It is also worth mentioning that pomace is an easily spoiled product, and without the proper processing, it cannot be stored for a long time. Thus, this research aimed to obtain optimal parameters for extraction, preserving the antioxidant characteristics. The optimal range of the following parameters for extraction was determined: the temperature for drying 45-50 °C, grinding level 1.5 mm, diluent concentration 70% ethanol/water solvent, extraction module 1:20, extraction temperature 50-55 °C, and duration 2 h. This determination of technological parameters of extraction was done according to the best physical-chemical measures and antioxidant activity level. The physical-chemical tests were performed according to the European Union standards. These parameters can produce an extract with distinct antioxidant characteristics that can be used in the food industry as a natural antioxidant. The extract with distinct antioxidant properties was obtained, which can be used in the food industry as a natural antioxidant.

Epidemiological study of Colletotrichum spp. associated with Enterolobium cyclocarpum (Jacq.) Griseb. and Platymiscium pinnatum (Jacq.) Dugand in the Colombian Caribbean Region

Epidemiological analyzes of foliar diseases associated with Colletotrichum spp. in Enterolobium cyclocarpum and Platymiscium pinnatum were performed under field conditions and without any type of intervention. At the Universidad del Magdalena (Santa Marta, Colombia), four trees for each species and four equidistant monitoring sites per tree were established. The incidence and severity were recorded for 33 weeks (March to November 2016), including two follow-up periods: dry and rainy season. Disease development curves were elaborated. Moreover, the development rate (r) and the area under the disease progress curve (AUDPC) were calculated for each follow-up period. The effect of the meteorological variables was statistically analyzed by correlation and multiple regression. In E. cyclocarpum, the highest incidence and severity were recorded between September and November with 100 and 19.6%, respectively, showing a positive correlation with relative humidity and negative with average temperature, solar radiation and wind speed. In P. pinnatum, the maximum values of incidence and severity were observed between March and April with 68.9 and 1.3%, respectively. However, correlation analyzes did not support their relationship with the environmental factors. The r values during the dry months were 0.136 and 0.107 units week-1 and the AUDPCs were calculated at 51 and 4 units week-1 for E. cyclocarpum and P. pinnatum, respectively. In the rainy months, the r values were 0.187 and 0.016 units week-1 and the AUDPCs were 186 and 2 units week-1, respectively. In conclusion, the development of the disease varies according to the forest species, time of year and some meteorological variables.

Optimization of the extraction and precipitation process of a leaf protein concentrate from Moringa oleifera Lam.

This study aimed to determine the best extraction and precipitation conditions of Moringa oleifera Lam. leaf protein. The influence of pH (10, 11, 12) and the concentration of NaCl (0, 0.25, 0.5) for the protein extraction process were studied through a Completely Randomized Design (CRD) with factorial arrange 32. The combination of pH 11 and 12 with 0 M NaCl had the best yield (P<0.05). The treatment of pH 11 without NaCl followed a precipitation stage for its purification, and the effect of different levels of pH (4, 4.5, 5) and temperature (40, 60, 80 °C) were evaluated using a CRD with factorial arrange 22 and 6 central points. The temperature did not affect the yield of the process in a significant way and the amount of precipitate was maximized at pH 4 and 4.5. From 100 g of the dry leaf, 7.26±0.19 g of protein was isolated with a recovery of 26.93±0.22 g 100 g-1 from the total protein. Due to their astringency and bitterness, consuming large amounts of Moringa oleifera Lam leaves is not a solution; therefore, obtaining a leaf proteinconcentrate could be useful for diverse applications in nutritional supplements, and as raw material for functional products development.

Agri-food safety optimized by blockchain technology: review

Blockchain technology is a distributed database, an innovation tool in the agri-food supply chain in processes such as production, distribution, marketing. In this research work, the blockchain technology application in agri-food security processes was evaluated, establishing the best conditions for its adoption in companies, this proposal synthesizes the contributions as a disruptive technology, for this, the information was collected from the period 2018-2020 from the Scopus and Web of Science bases, performing an analysis of the information using the Atlas TI 8.4 software, establishing the focus of the research on a network of codes suggested by some authors. It was found that the contribution of Blockchain for the years of study was traceability 26%, supply chain 17.5%, technological development 10.4%, trust 9.8%, among others. It is concluded that establishing the theoretical link between technology and traceability processes in supply chains, traceability in the agri-food sector is essential to certify information of interest to the stakeholder group. This is because traceability is the transcendental element of the food safety system that allows guaranteeing control in the supply chain when processes are being recorded and enriching the databases, which can be available to the final consumer to check the details of the production cycle and that technological elements generate competitiveness in companies with blockchain in their procedures, promote high levels of transparency, data security, decentralization, among other terms associated with trust, and a better relationship with the consumer is developed and a greater number of sale increasing profitability.

Quality of tomato (Solanum lycopersicum L.) fruits inoculated with Escherichia coli under different storage conditions

The study evaluated the effect of storage temperatures of 7 and 22 °C for 168 h on tomatoes (Charleston cv.) inoculated with 107 CFU mL-1 of the enterotoxigenic Escherichia coli pathogroup (ETEC) strain on color indexes (hue angle, h°, and chroma, C*), firmness, titratable acidity (% citric acid), ascorbic acid, total soluble sugars and reducing sugars (glucose, fructose, and sucrose). ETEC survived with populations of 7 and 9.2 Log CFU g-1 at 7 and 22 °C, respectively until 120 h. Bacterial adherence and colonization under both storage conditions were confirmed by scanning electron microscopy. The index C* and ascorbic acid had higher values at 22 °C, while the parameters h°, firmness, and citric acid had lower values at the same storage temperature. At 7 °C, the concentration of total soluble sugars was affected; glucose and fructose showed lower values (0.054 and 0.057 g 100 g-1, respectively). Finally, the inoculated fruits exhibited significant differences in the parameters of consumer preference of fresh tomatoes such as color, firmness, sugars, and organic acids, which were affected depending on the storage temperature.