Improvements in fermentation and nutritive quality of elephant grass [Cenchrus purpureus (Schumach.) Morrone] silages: a review.

Elephant grass [Pennisetum purpureum Schumach. syn. Cenchrus purpureus (Schumach.) Morrone], also known as Napier grass and King grass, includes varieties Taiwán, Gigante, Merkerón, Maralfalfa, and others. The grass achieves high biomass production in tropical-subtropical, temperate, and arid areas. The high-water concentration of elephant grass suggests that ensiling could offer an alternative way to preserve the nutritional quality of the grass during storage, however, some considerations should be addressed because of the particularities of the grass. Ensiling elephant grass may produce adequate fermentation but could suffer effluent losses and subsequent losses of nutrients due to leaching. To improve fermentation and nutrient characteristics of elephant grass silages, several studies were conducted with the inclusion of additives. Lactic acid bacteria inocula have reduced pH and increased crude protein content of elephant grass silage, but aerobic stability of silages could be affected by the bacterial inoculation. There is limited information, however, on the potential of different silage inoculants to reduce growth of spoilage microorganisms during the aerobic phase of silage prepared with elephant grass. Exogenous fibrolytic enzymes also may improve elephant grass silage quality by enhancing microbial fiber-degradation with subsequent increase in lactic acid and its associated pH reduction. Another study approach to improve fermentation and nutritional quality of elephant grass silages involved the addition of different feeds at ensiling, including conventional feeds such corn, wheat, rice bran, and molasses or alternative feeds such as different dehydrated by-products obtained from the food industries of juice and jelly. In the manuscript, the presented scientific information shows the great potential of the different manipulations to improve the quality of elephant grass silages and with possible enhance of the economic profit and sustainability of livestock farming in the tropical areas.

Quantification of Major Inorganic Contaminants in a Mediterranean Coastal Lagoon with a Large Dystrophic Crisis.

In August 2021, the Mar Menor, a saltwater lagoon located in the Region of Murcia (Spain), suffered a tragic environmental episode of dystrophic crisis and anoxia. The appearance of numerous dead fish in different areas of the lagoon over the course of days put all the authorities and the population of the area on alert. This paper shows a case study of what happened in the lagoon in terms of the presence of the most common inorganic pollutants. Measurements of the concentration of nitrogen species, phosphates and main heavy metals were carried out at different sampling sites in the Mar Menor from May 2021 to November 2022. Chemical analyses were carried out for each of the species under study. These analyses provide valuable information about the dystrophic crisis caused by a classic eutrophication process that began with the excessive nutrient input into the Mar Menor. Ion chromatography and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were used as instrumentation for the quantification of these samples. The species whose values were greatly increased after the tragic episode described above were nitrates. The concentration varied significantly at the different sampling sites throughout the study. On the last sampling date, decreased concentrations of all the species were measured at each of the sampling sites, coinciding with the apparent good state of the lagoon.

Colorimetric analysis platform based on thin layer chromatography for monitoring gluten cross-contamination in food industry.

Monitoring of the accidental presence of gluten (Glu), resulting from cross-contamination, is imperative in different industries, in particular food industry. The objective of this study was the development of an analytical platform utilizing thin-layer chromatography (TLC) with colorimetric read-out for making binary (yes/no) decisions on surfaces and/or point of these industries. The composition of the extractive phase was optimized with commercial products used in cleaning processing lines. Subsequently, an exploration of TLC separation and detection was undertaken. CN-modified nanosilica plates and 30:70 acetonitrile:water were used to achieve a selective signal for Glu residues. The study of the detection performance showed that both spectroscopic measurement and image analysis were resulted in satisfactory results for quantitate analysis (RSD = 5 %, LOD = 0.12 mg). The practical application of the proposed methodology on surfaces of the food processing lines. This work demonstrated the operational feasibility in detecting gluten cross-contaminations within the food processing industry.

Factores socioeconómicos asociados por nivel de inseguridad alimentaria en adultos mexicanos con diabetes mellitus durante la pandemia de la COVID-19.

OBJETIVOS: estimar la prevalencia de la inseguridad alimentaria e identificar los factores socioeconómicos asociados en adultos mexicanos con diabetes mellitus, durante la pandemia de la COVID-19. MÉTODOS: estudio transversal, análisis secundario de los datos de la Encuesta Nacional de Salud y Nutrición 2020 sobre la COVID-19. Se estudió a 1 232 individuos que representan a 9 569 330 adultos con diabetes mellitus. La inseguridad alimentaria se midió utilizando la Escala Latinoamericana y Caribeña de Seguridad Alimentaria adaptada para México. Se realizó un modelo de regresión logístico binario para cada nivel de inseguridad alimentaria. Se calcularon razón de momios e intervalos de confianza al 95 %. Un valor de p < 0.05 fue estadísticamente significativo. RESULTADOS: el 64.8 % presentó inseguridad alimentaria: 40.7 % leve, 14.2 % moderada y 9.9 % severa. Los factores asociados a inseguridad alimentaria leve fueron: nivel socioeconómico muy bajo (RM 2.6), pérdida del empleo de algún miembro del hogar (RM 2.0) y reducción de gastos en alimentación (RM 5.0); para inseguridad moderada la RM fue de 7.7, 3.4 y 18.6 y en severa la RM 7.1, 3.0 y 46.7, respectivamente. CONCLUSIONES: la COVID-19 ha tenido efectos inmediatos en la inseguridad alimentaria de la población de adultos mexicanos con diabetes mellitus. Identificar los factores socioeconómicos asociados es prioritario para llevar a cabo políticas públicas que permitan redirigir los recursos y cubrir necesidades básicas como la alimentación.

Mejora funcional en personas mayores frágiles mediante el programa de ejercicios Vivifrail, durante dos años de pandemia / Functional improvement in frail older adults through the Vivifrail exercise program, during two years of pandemic

Antecedentes y objetivo El ejercicio físico aumenta la capacidad funcional en personas mayores ayudando a evitar o retrasar situaciones de dependencia. En este estudio se evalúa el impacto de una intervención de ejercicio físico multicomponente basado en el programa Vivifrail realizado en un centro de atención primaria en dos años coincidente con la pandemia COVID. Sujetos y métodos Diseño descriptivo longitudinal con comparación antes-después sin grupo control. Personas mayores de 65 años con alteración de funcionalidad medida mediante test de ejecución, adscritos al centro de salud El Palo, Málaga. La intervención consiste en dos sesiones semanales grupales de ejercicio físico guiadas por monitor, según programa Vivifrail. Variables: índice de Barthel, velocidad de la marcha, categoría Vivifrail, calidad de vida (EuroQol 5-D [EQ-5D]) uso de ayudas para la marcha, número de caídas el año previo. Mediciones: basal, segunda (un año) y final (dos años). Análisis test de Kruskal-Wallis, nivel significación 0,05. Resultados Se incluyen evaluaciones de 20 pacientes. Entre primera y segunda valoración, objetivamos modificación significativa en uso de ayudas para la marcha (p 0,01) y categorías Vivifrail: de B inicial, 50% permanecen, 25% pasa a A, 16,7% C2 y 8,3% D (p 0,048). En análisis valoración basal-final, encontramos mejora estadísticamente significativa en calidad de vida medida por EQ-5D (aumento medio 24 puntos en medición de calidad de vida hoy, termómetro EQ-5D, con IC 95% (9,6-38,3), p 0,004) y de categoría Vivifrail (n=10) 60% permanecen categoría B y 40% pasan a D (autónomos) (p<0,0001). Se observa tendencia a mejoría en velocidad de la marcha, tiempo de paseo diario y número de caídas, sin alcanzar significación estadística. Conclusiones El ejercicio físico multicomponente mejora la calidad de vida percibida medida mediante EQ-5D y produce una tendencia a la mejora en capacidad funcional, estado de ánimo y número de caídas (AU)

Background and objective Physical exercise increases functional capacity in older adults, helping to prevent or delay dependence. This study evaluates the impact of a multicomponent physical exercise intervention based on the Vivifrail program, conducted in a primary care center over two years coinciding with the COVID pandemic. Subjects and methods Descriptive longitudinal design with before-after comparison without control group. Participants were older than 65 years old with functional impairment measured by execution test, enrolled in the El Palo Health Center, Málaga. The intervention consists of two weekly group sessions of physical exercise guided by a monitor, according to the Vivifrail program. Variables: Barthel Index, Gait Speed, Vivifrail Category, Quality of Life (EuroQol 5-D [EQ-5D]), use of walking aids, number of falls in the previous year. Measurements: baseline, second (one year) and final (two years). Analysis of the Kruskal-Wallis test, significance level 0.05. Results Twenty patients were evaluated. Between the first and second evaluation, we observed a significant modification in the use of walking aids (p 0.01) and Vivifrail categories: from an initial B category, 50% remained, 25% moved to A, 16.7% to C2 and 8.3% to D (p 0.048). In the analysis of the baseline-final evaluation, we found a statistically significant improvement in quality of life measured by EQ-5D (mean increase of 24 points in today's quality of life measurement, EQ-5D thermometer, with 95% CI (9.6-38.3), p 0.004) and Vivifrail category (n=10) with 60% remaining in category B and 40% moving to D (autonomous) (p<0.0001). There was a trend towards improvement in gait speed, daily walking time, and number of falls, but without reaching statistical significance. Conclusions Multicomponent physical exercise improves perceived quality of life measured by EQ-5D and leads to a trend towards improvement in functional capacity, mood, and number of falls (AU)

LysR-type transcriptional regulators: state of the art.

The LysR-type transcriptional regulators (LTTRs) are DNA-binding proteins present in bacteria, archaea, and in algae. Knowledge about their distribution, abundance, evolution, structural organization, transcriptional regulation, fundamental roles in free life, pathogenesis, and bacteria-plant interaction has been generated. This review focuses on these aspects and provides a current picture of LTTR biology.

[Functional improvement in frail older adults through the Vivifrail exercise program, during two years of pandemic]. / Mejora funcional en personas mayores frágiles mediante el programa de ejercicios Vivifrail, durante dos años de pandemia.

BACKGROUND AND OBJECTIVE: Physical exercise increases functional capacity in older adults, helping to prevent or delay dependence. This study evaluates the impact of a multicomponent physical exercise intervention based on the Vivifrail program, conducted in a primary care center over two years coinciding with the COVID pandemic. SUBJECTS AND METHODS: Descriptive longitudinal design with before-after comparison without control group. Participants were older than 65 years old with functional impairment measured by execution test, enrolled in the El Palo Health Center, Málaga. The intervention consists of two weekly group sessions of physical exercise guided by a monitor, according to the Vivifrail program. VARIABLES: Barthel Index, Gait Speed, Vivifrail Category, Quality of Life (EuroQol 5-D [EQ-5D]), use of walking aids, number of falls in the previous year. MEASUREMENTS: baseline, second (one year) and final (two years). Analysis of the Kruskal-Wallis test, significance level 0.05. RESULTS: Twenty patients were evaluated. Between the first and second evaluation, we observed a significant modification in the use of walking aids (p 0.01) and Vivifrail categories: from an initial B category, 50% remained, 25% moved to A, 16.7% to C2 and 8.3% to D (p 0.048). In the analysis of the baseline-final evaluation, we found a statistically significant improvement in quality of life measured by EQ-5D (mean increase of 24 points in today's quality of life measurement, EQ-5D thermometer, with 95% CI (9.6-38.3), p 0.004) and Vivifrail category (n=10) with 60% remaining in category B and 40% moving to D (autonomous) (p<0.0001). There was a trend towards improvement in gait speed, daily walking time, and number of falls, but without reaching statistical significance. CONCLUSIONS: Multicomponent physical exercise improves perceived quality of life measured by EQ-5D and leads to a trend towards improvement in functional capacity, mood, and number of falls.

Silencing of the Laccase (lacc2) Gene from Pleurotus ostreatus Causes Important Effects on the Formation of Toxocyst-like Structures and Fruiting Body.

A wide variety of biological functions, including those involved in the morphogenesis process of basidiomycete fungi, have been attributed to laccase enzymes. In this work, RNA interference (RNAi) was used to evaluate the role of the laccase (lacc2) gene of Pleurotus ostreatus PoB. Previously, transformant strains of P. ostreatus were obtained and according to their level of silencing they were classified as light (T7), medium (T21) or severe (T26 and T27). The attenuation of the lacc2 gene in these transformants was determined by RT-PCR. Silencing of lacc2 resulted in a decrease in laccase activity between 30 and 55%, which depended on the level of laccase expression achieved. The silenced strains (T21, T26, and T27) displayed a delay in the development of mycelium on potato dextrose agar (PDA) medium, whereas in the cultures grown on wheat straw, we found that these strains were incapable of producing aerial mycelium, primordia, and fruiting bodies. Scanning electron microscopy (SEM) showed the presence of toxocyst-like structures. The highest abundance of these structures was observed in the wild-type (PoB) and T7 strains. However, the abundance of toxocysts decreased in the T21 and T26 strains, and in T27 they were not detected. These results suggest that the presence and abundance of toxocyst-like structures are directly related to the development of fruiting bodies. Furthermore, our data confirm that lacc2 is involved in the morphogenesis process of P. ostreatus.

Viability and removal assessment of Escherichia coli and Salmonella spp. by real-time PCR with propidium monoazide in the hygienization of sewage sludge using three anaerobic processes.

Sewage sludge should be stabilized for its beneficial use and pathogens, among other factors, should comply with environmental regulations. Three sludge stabilization process were compared to assess their suitability for producing Class A biosolids: MAD-AT (mesophilic (37 °C) anaerobic digestion (MAD) followed by an alkaline treatment (AT)); TAD (thermophilic (55 °C) anaerobic digester); and TP-TAD (mild thermal (80 °C, 1 h) pretreatment (TP) followed by a TAD). E. coli and Salmonella spp. were determined, differentiating three possible states: total cells (qPCR), viable cells using the propidium monoazide method (PMA-qPCR), and culturable cells (MPN). Culture techniques followed by the confirmative biochemical tests identified the presence of Salmonella spp. in PS and MAD samples, while the molecular methods (qPCR and PMA-qPCR) showed negative results in all samples. The TP + TAD arrangement reduced the concentration of total and viable E. coli cells in a greater extent than the TAD process. However, an increase of culturable E. coli was observed in the corresponding TAD step, indicating that the mild thermal pretreatment induced the viable but non-culturable state in E. coli. In addition, the PMA technique did not discriminate viable from non-viable bacteria in complex matrices. The three processes produced Class A biosolids (fecal coliforms < 1000 MPN/gTS and Salmonella spp, < 3 MPN/gTS) maintaining compliance after a 72 h storage period. It appears that the TP step favors the viable but not culturable state in E. coli cells, a finding that should be considered when adopting mild thermal treatment in sludge stabilization process arrangements.

Laccase Production from Agrocybe pediades: Purification and Functional Characterization of a Consistent Laccase Isoenzyme in Liquid Culture.

Laccases are valuable enzymes as an excellent ecological alternative for bioremediation issues because they can oxidize persistent xenobiotic compounds. The production and characterization of extracellular laccases from saprotrophic fungi from disturbed environments have been scarcely explored, even though this could diversify their functional characteristics and expand the conditions in which they carry out their catalysis. Agrocybe pediades, isolated from a disturbed forest, produces an extracellular laccase in liquid culture. The enzyme was purified, identified and characterized. Copper and hexachlorobenzene do not function as inducers for the laccase produced. Partial amino acid sequences were obtained by LC-MS/MS that share similarity with laccases from other fungi. Purified laccase is a monomer with a molecular mass between 55-60 kDa and had an optimum activity at pH 5.0 and the optimum temperature at 45 °C using 2,6-dimethoxyphenol (2,6-DMP) as substrate. The Km and Vmax also determined with 2,6-DMP were 100 µM and 285 µmol∙min-1∙mg-1, respectively, showing that the laccase of A. pediades has a higher affinity for this substrate than that of other Agaricales. These features could provide a potential catalyst for different toxic substrates and in the future laccase could be used in environmental recovery processes.

Point mutations in the glycosyltransferase domain of the pbp1a gene in amoxicillin-resistant Helicobacter pylori isolates.

INTRODUCTION: Helicobacter pylori (H. pylori) eradication treatment includes a proton pump inhibitor and two antibiotics: amoxicillin and clarithromycin. The goal of that treatment is to eradicate the infection in at least 90% of the patients. Failure to eradicate the infection can have multiple causes, among which is the presence of point mutations in the antimicrobial target genes. OBJECTIVE: To characterize the mutations present in the pbp1a gene and their possible association with resistance to amoxicillin in vitro. METHODOLOGY: Susceptibility to amoxicillin was evaluated in 147 isolates of H. pylori from the Colombian municipality of Túquerres. PCR amplification and sequencing of the glycosyltransferase domain of the pbp1a gene were carried out on Túquerres isolates, and the association between mutations and resistance was evaluated. RESULTS: A total of 5.4% (8/147) Túquerres isolates were resistant to amoxicillin in vitro. PCR amplification of the glycosyltransferase domain of the pbp1A gene was performed on 87.5% of the amoxicillin-resistant isolates in vitro, and in the DNA sequencing analysis, a total of 2 changes of amino acids from 3 DNA mutations that encoded the PBP1A-1 protein were observed. CONCLUSION: The present study is the first report on pbp1a gene mutations in H. pylori isolates coming from a population in Túquerres. Mutations that have not been reported in previous studies were found.

Complete and simultaneous removal of ionic silver and silver nanoparticles by using an ionic liquid supported on a magnetic nanoparticle core.

The global pandemic situation due to COVID-19 has given rise to the massive use of disinfectant products, many of them based on silver atoms. After the use of these products, the silver passes into the aqueous effluents, becoming an emerging contaminant in waters. In this work, a novel procedure for the total and simultaneous removal of ionic and nanomeric silver in aqueous samples is introduced, employing magnetic nanoparticles wrapped with an ionic liquid (Fe3O4@IL) as a removal agent. Experimental variables such as pH, contact time, temperature, as well as pollutant and removal agent doses were studied to achieve the total elimination, exhibiting exceptional conditions for the removal of different concentrations of silvers species in water. The approach achieves 100% removal efficiency for the simultaneous removal of both silver species, goal not achieved previously. Also, 100% removal efficiency is reached for the both species separately, since ionic silver is adsorbed onto the Fe3O4, while nanomeric silver is extracted in the IL. Particularly, for concentrations within the range 50-200 µg L-1, total removal efficiency was reached for a wide range of temperatures and a pH range 7-9, achieved in just 15 min, for all cases. Additionally, the doses of Fe3O4@IL employed to remove all concentrations of silver were 13.7 mg. Characterization of Fe3O4@IL surfaces before and after the process was performed by means of Field Effect Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. Fe3O4@IL was recycled by employing 100 µL of 1% HNO3 solution, allowing its use for 10 additional silver removal cycles without loss of efficiency. The study of adsorption kinetics and equilibrium isotherms reveal a Freundlich-type adsorption, which suggests affinity between sites in the complex surface of Fe3O4@IL, and Elovich kinetics, indicative of chemisorption onto a heterogeneous surface, while the temperature shows no effect on the results.

La percepción local de la transformación del paisaje en San Juan Teposcolula, Oaxaca México / Local perception of landscape transformation in San Juan Teposcolula, Oaxaca Mexico

RESUMEN Los suelos degradados y sin plantas de la Mixteca Alta de Oaxaca (México) fueron, por un largo tiempo, como el paisaje habitual de la región; sin embargo, la organización de los campesinos y las intervenciones de los programas de reforestación configuraron un nuevo paisaje con bosques. Desde 1935, la Mixteca Alta experimenta reforestaciones en su territorio, lo que originó una paulatina mejoría del paisaje. Para estudiar esta transformación, se aplicó una metodología cualitativa, la cual, se apoyó en la planeación de escenarios y de entrevistas semiestructuradas con las autoridades comunales. Los resultados muestran que los entrevistados perciben a las forestaciones como el factor que cambió su paisaje y, al mismo tiempo, identifican los servicios ecosistémicos que les brindan, como un clima local más agradable, la aparición de pequeños arroyos y fauna silvestre. Los resultados del estudio muestran la intención que tienen los entrevistados para hacer uso y aprovechamiento de las plantaciones.

ABSTRACT The degraded and deforested soils of the Mixteca Alta of Oaxaca (Mexico) were for a long time the usual landscape of the region. However, the organization of the farmers and the interventions of reforestation programs configured a new forested landscape. Since 1935, the Mixteca Alta has been subject to reforestation processes in its territory, which has led to a gradual improvement of the landscape. To study this transformation, a qualitative methodology was applied, based on scenario planning and semi-structured interviews with community authorities. The results show that the interviewees perceive the forestations as the factor that changed their landscape and at the same time identify the ecosystem services they provide, such as a more pleasant local climate, the appearance of small streams and wildlife. The results of the study show the intention of the interviewees to use and take advantage of the plantations.