Multivariate Statistical Techniques: A New Approach to Identify the Commercial Properties of Mixtures of Flours of Lentinula edodes and Cocoa Pod Husk.

Lentinula edodes is known to show high nutritional and organoleptic properties and can be mixed with different by-products in the production of new foods with important functional characteristics. Cocoa pod husk (CPH) is the main by-product in the cocoa industry and presents important bioactivities. In this research, two mixtures were applied based on Lentinula edodes mushroom flour from fifty different strains (strain 1 to strain 50) and cocoa pod husk flour (CPHF): 60% Lentinula edodes mushroom flour from each strain mixed with 40% CPHF (Mixture 1), and 80% Lentinula edodes mushroom flour from each strain mixed with 20% CPHF (Mixture 2). The parameters evaluated were moisture, proteins, fat, total dietary fiber (TDF), ash, carbohydrates, antioxidant capacity, antimicrobial activity, pH and water activity (aw). The multivariate statistical techniques evaluated those samples that exhibited the highest degree of correlation with the distinct chemical and commercial parameters, showing that sample 13 of both mixture flours (M1 and M2) obtained by the mushrooms of L. edodes (strain 13) with CPH indicated the higher significant of the parameters. In addition, the sensory test of the best flour (sample 13) was applied to 50 panelists, presenting the best sensory characteristics, such as color, aroma, texture and general acceptability.

Susceptibility to Organophosphates in Culex quinquefasciatus from Colombia.

Susceptibility to organophosphates was evaluated in 2 populations of Culex quinquefasciatus from the department of Atlantico, Colombia. Bioassays for temephos, malathion, and pirimiphos-methyl were performed with 3rd-stage larvae and adult females of Cx. quinquefasciatus from the municipalities of Soledad and Puerto Colombia, following the methods of the World Health Organization and Centers for Disease Control and Prevention, respectively. The median lethal concentration (LC50) and 90% lethal concentration (LC90) resistance ratios (RRLC50 and RRLC90) were determined for each insecticide in the field populations evaluated, using the Cartagena strain as the susceptible control. Relative to LC50 and LC90 of the Cartagena strain, the population from Puerto Colombia was moderately resistant to temephos (RRLC50 5.7-fold) and malathion (RRLC50 8.6-fold, RRLC90 9-fold) and susceptible to pirimiphos-methyl (RRLC50 and RRLC90 < 5-fold). The population from Soledad was susceptible to temephos and pirimiphos-methyl (RRLC50 and RRLC90 < 5-fold) and showed moderate resistance to malathion (RRLC50 7.5-fold). It is important to emphasize that routine monitoring of insecticide resistance in Cx. quinquefasciatus helps us detect resistance early and improve the effectiveness of control strategies.

Data-Mining Techniques: A New Approach to Identifying the Links among Hybrid Strains of Pleurotus with Culture Media.

In this study, a data set of mycelial and cultural characteristics of hybrid strains of Pleurotus ostreatus and Pleurotus djamor were analyzed using three data-mining techniques: the K-medoids clustering algorithm, PCA biplot and the association rules algorithm. The characteristics evaluated were as follows: maximum velocity; lag phase; biomass; and exopolysaccharides content in the cultivation of 50 hybrid strains of Pleurotus ostreatus and 50 hybrid strains of Pleurotus djamor. Different mixtures of culture media were used to supplement Ecuadorian agricultural products. Data of the parameters obtained in the experimental methods were grouped into four clusters, obtaining a presentation of the hybrid strains of Pleurotus with a higher relation to each characteristic measured. Data-mining tools showed the hybrid strains cultivated on solid-culture media (M1 = malt extract agar and rice flour) and liquid-culture media (L1 = maltose, yeast extract and rice flour) presented the highest mycelial and cultural characteristics. These results are good indicators to improve the industrial production of edible fungi by using rice flour in the cultivation, contributing to the mushroom market and circular economy.

Application of K-Means Clustering Algorithm to Commercial Parameters of Pleurotus spp. Cultivated on Representative Agricultural Wastes from Province of Guayas.

Data of the commercial parameters of Pleurotus ostreatus and Pleurotus djamor were analyzed using the data mining technique: K-means clustering algorithm. The parameters evaluated were: biological efficiency, crop yield ratio, productivity rate, nutritional composition, antioxidant and antimicrobial activities in the production of fruit bodies of 50 strains of Pleurotus ostreatus and 50 strains of Pleurotus djamor, cultivated on the most representative agricultural wastes from the province of Guayas: 80% sugarcane bagasse and 20% wheat straw (M1), and 60% wheat straw and 40% sugarcane bagasse (M2). The database of the parameters obtained in experimental procedures was grouped into three clusters, providing a visualization of the strains with a higher relation to each parameter (vector) measured.

Influence of Calcium Silicate on the Chemical Properties of Pleurotus ostreatus var. florida (Jacq.) P. Kumm.

Supplementation of mushroom substrates has been linked to a higher resistance against insect pests, although few studies show the impact of this supplementation on the different agronomical parameters of mushrooms or even their chemical composition. In this work, the variation in the biological and chemical composition of oyster mushroom (Pleurotus ostreatus var. florida (Jacq.) P. Kumm) was analysed after varying the substrate supplementation of calcium silicate (0, 0.5, 1, 2, and 4% (w/w%)) during two harvest flushes. Overall, supplementation did not change the weight, the number of fruiting bodies, biological efficiency, yield ratio, and productivity rate of the mushrooms, although the harvest flushes did show significant differences. Furthermore, slight changes were found in the chemical composition with an increase in vitamin D2 and tocopherols for the mushrooms with higher amounts of calcium silicate. Overall, the substrate supplementation did not seem to induce expressive changes or decrease production yields, and can, therefore, continue to be researched as a potential application to fight agronomical pests.

Susceptibility to Pyrethroids and the First Report of L1014F kdr Mutation in Culex quinquefasciatus (Diptera: Culicidae) in Colombia.

The use of insecticides for the control of Aedes aegypti (L.) (Diptera: Culicidae) in Colombia has indirectly influenced the susceptibility status of Culex quinquefasciatus Say populations. We evaluated pyrethroid susceptibility in two populations of Cx. quinquefasciatus in the Atlantico Department of Colombia and its possible resistance mechanism (kdr mutation). Bottle bioassays were performed for permethrin, deltamethrin, and λ-cyhalothrin in female mosquitoes of Cx. quinquefasciatus. The resistance ratios (RRs) for KC50 and LC50 for each insecticide in the field populations examined were determined, using the Cartagena strain as the susceptible control. The L1014F kdr mutation was identified in the para gene of the voltage-gated sodium channel (vgsc), along with its allelic and genotypic frequency. Low knockdown resistance (RRKC50) to deltamethrin was found in Puerto Colombia and Soledad populations as well as low resistance to λ-cyalothrin in this latter population. Moderate knockdown resistance to permethrin was found in both populations. At 24 h post-exposure on the other hand, there was low resistance (RRLC50) to permethrin in Puerto Colombia and moderate resistance in Soledad. Moderate resistance to deltamethrin was found in Puerto Colombia and low resistance in Soledad. Low resistance to λ-cyhalothrin was seen in Puerto Colombia and moderate resistance in Soledad. Variability was found in the susceptibility to the pyrethroids in the populations of Cx. quinquefasciatus evaluated, and the L1014F kdr mutation is reported for the first time as a possible pyrethroid resistance mechanism in this species in Colombia.

Characterization of Pleurotus djamor neohaplonts recovered by production of protoplasts and chemical dedikaryotization.

Production of hybrid strains is accomplished by mating monosporic isolates or neohaplonts, obtained either by chemical dedikaryotization or by production of protoplast. However, differences in growth rate among recovered neohaplonts have been reported. The presence of phenotypic and genetic changes among the neohaplonts recovered either by chemical dedikaryotization or by production of protoplast, was evaluated by measuring growth and morphology, and by molecular characterization using six ISSR markers to identify polymorphisms. Neohaplonts recovered by both methods presented variation in growth rate depending on their compatibility type and recovery method. Using ISSR markers, 59.2% polymorphism was established. Neohaplonts recovered by both monokaryotization procedures presented differences in growth rate and polymorphism.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water: Oyster mushroom and substrate treatment.

The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20min by using two different procedures: (i) 0.5-2.0% Ca(OH)2 in 100L water, and (ii) 50-250L water. As a result, 1% Ca(OH)2 dissolved in 100L water and 3.5kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water

Abstract The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20 min by using two different procedures: (i) 0.52.0% Ca(OH)2 in 100 L water, and (ii) 50250 L water. As a result, 1% Ca(OH)2 dissolved in 100 L water and 3.5 kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water

Abstract The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20 min by using two different procedures: (i) 0.5-2.0% Ca(OH)2 in 100 L water, and (ii) 50-250 L water. As a result, 1% Ca(OH)2 dissolved in 100 L water and 3.5 kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

Aislamiento e Identificación de Hongos filamentosos tolerantes a aceites dieléctricos usados y los Bifenilos Policlorados (PCBs) de suelos contaminados / Isolation and Identification of Filamentous Fungi Tolerant to Used Dielectric Oils and Contaminated Soil Polychlorinated biphenyls (PCBs)

Los PCBs por sus propiedades físicas y químicas son usados en diferentes sectores industriales; sus productos de desechos y su almacenamiento inadecuado han contaminado ambientes como suelos y aguas poniendo en peligro la supervivencia en los ecosistemas. Sin embargo, algunos seres vivos son capaces de adaptarse. Los bifenilos policlorados (PCBs) son compuestos orgánicos de hidrocarburos sintéticos formados por dos anillos de benceno unidos por un enlace de carbono; comprenden una clase de 209 compuestos individuales, isómeros y congéneres. Su objetivo fue aislar e identificar hongos filamentosos capaces de tolerar y adaptarse para sobrevivir en condiciones adversas en el ecosistema suelo contaminado por el xenobiótico PCBs, presente en aceites dieléctricos usados (ADU) en un sector industrial de Barranquilla. Los hongos aislados de los géneros Aspergillus sp, Alternaría sp, Phoma sp, Rhizopus sp. sobrevivieron a concentraciones de ADU 20 %, y a 200 ppm de PCBs

PCBs for their physical and chemical properties are used in different industrial sectors; waste products and inadequate storage have polluted environments such as soils and water that endanger ecosystem survival. However, some living beings are able to adapt. Polychlorinated biphenyls (PCBs) are organic synthetic hydrocarbon compounds formed by two benzene rings bonded by a carbon bond, comprise a class of 209 individual compounds, isomers and congeners. Its objective was the isolation and identification of filamentous fungi capable of tolerating and adapting to survive in adverse conditions in the soil ecosystem contaminated by the xenobiotic PCBs, present in used dielectric oils (ADU) in an industrial sector of Barranquilla. The isolated fungi of the genus Aspergillus sp, Alternaria sp, Phoma sp, Rhizopus sp. survived concentrations of 20% ADU, and 200 ppm of PCBs.

Outbreak of multiresistant OXA-24- and OXA-51-producing Acinetobacter baumannii in an internal medicine ward.

Here we describe the clinical, microbiological, epidemiological, and molecular characterization of an outbreak of multidrug-resistant Acinetobacter baumannii (MRAB) involving 5 patients admitted to the internal medicine ward of our hospital. Over a 6-week period, 5 MRAB isolates were recovered from 5 patients, including 1 with fatal meningitis, 3 with skin and soft tissue infections, and 1 with respiratory colonization. One sample obtained during environmental monitoring in the ward was A. baumannii-positive. According to the pulsed-field gel electrophoresis typing results, the strains isolated from all patients and the environmental sample belonged to a single clone, identified as ST79 by multilocus sequence typing. The blaOXA-24 and blaOXA-51 carbapenemases were detected in all isolates. Four patients died, but only the death of the meningitis patient was probably related to the A. baumannii infection. The infection source was probably the hands of the healthcare workers because the outbreak strain was isolated from the surface of a serum container. The results of the present study revealed the importance of strict adherence to control measures by all healthcare workers because the consequences of noncompliance can be very serious.

Synthesis and structural study of highly constrained hybrid cyclobutane-proline γ,γ-peptides.

Two diastereomeric series of hybrid γ,γ-peptides derived from conveniently protected derivatives of (1R,2S)- and (1S,2R)-3-amino-2,2-dimethylcyclobutane-1-carboxylic acid and cis-4-amino-L: -proline joined in alternation have efficiently been prepared through convergent synthesis. High-resolution NMR experiments show that these compounds present defined conformations in solution affording very compact structures as the result of intra and inter residue hydrogen-bonded ring formation. (R,S)-cyclobutane containing peptides adopt more twisted conformations than (S,R) diastereomers. In addition, all these γ-peptides have high tendency to aggregation providing vesicles of nanometric size, which were stable when allowed to stand for several days, as verified by transmission electron microscopy.