Levan Production by Suhomyces kilbournensis Using Sugarcane Molasses as a Carbon Source in Submerged Fermentation.

The valorization of byproducts from the sugarcane industry represents a potential alternative method with a low energy cost for the production of metabolites that are of commercial and industrial interest. The production of exopolysaccharides (EPSs) was carried out using the yeast Suhomyces kilbournensis isolated from agro-industrial sugarcane, and the products and byproducts of this agro-industrial sugarcane were used as carbon sources for their recovery. The effect of pH, temperature, and carbon and nitrogen sources and their concentration in EPS production by submerged fermentation (SmF) was studied in 170 mL glass containers of uniform geometry at 30 °C with an initial pH of 6.5. The resulting EPSs were characterized with Fourier-transform infrared spectroscopy (FT-IR). The results showed that the highest EPS production yields were 4.26 and 44.33 g/L after 6 h of fermentation using sucrose and molasses as carbon sources, respectively. Finally, an FT-IR analysis of the EPSs produced by S. kilbournensis corresponded to levan, corroborating its origin. It is important to mention that this is the first work that reports the production of levan using this yeast. This is relevant because, currently, most studies are focused on the use of recombinant and genetically modified microorganisms; in this scenario, Suhomyces kilbournensis is a native yeast isolated from the sugar production process, giving it a great advantage in the incorporation of carbon sources into their metabolic processes in order to produce levan sucrose, which uses fructose to polymerize levan.

Color and Stability of Anthocyanins of Chagalapoli (Ardisia compressa K.) Fruit Added to an Isotonic Beverage as Microcapsules and as Free Extract.

The demand for natural pigments in the food industry is increasing. Color and stability of anthocyanins of chagalapoli (Ardisia compressa K.) fruit added to an isotonic beverage as microcapsules and free extract were evaluated at two temperatures (4 and 25 °C) in the absence of light. Anthocyanins degradation followed first-order kinetics in the evaluated conditions. The stability of anthocyanins, measured by the variables reaction rate (K), half-life time (t1/2), and anthocyanin retention (AR), was affected significantly (p < 0.01) by temperature. At the end of storage at 4 °C, AR was 91.2 ± 0.28% and 89.63 ± 0.22% in the beverages with microcapsules (BM) and with anthocyanins from extract (BE), respectively, without a significant difference (p ≥ 0.05) between them. However, at 25 °C, AR in the BM was 53.72 ± 0.27%, a significantly lower value (p ≤ 0.05) than that in BE (58.83 ± 1.37%). The color difference values (ΔE) in beverages stored at 4 °C were 3.81 and 2.17 for BM and BE, respectively, while at 25 °C, it was 8.57 and 8.21, respectively. The most stable anthocyanin was cyanidin 3-galactoside. Chagalapoli anthocyanins, both as microcapsules or as an extract, are adequate for adding natural color to isotonic beverages.

Impact of Metarhizium robertsii on Adults of the Parasitoid Diachasmimorpha longicaudata and Parasitized Anastrepha ludens Larvae.

Biological control of the Mexican fruit fly, Anastrepha ludens, is mainly carried out by releasing parasitoids, such as Diachasmimorpha longicaudata, and by applying entomopathogenic fungi (EPF), such as Metarhizium anisopliae, Beauveria bassiana, or Isaria fumosorosea, which can be applied to the soil or dispersed using infective devices. The combined use of two or more biocontrol agents could improve A. ludens control, but IGP between natural enemies, if it occurs, may have negative effects. We evaluated the effects of EPF on D. longicaudata. First, we determined the susceptibility of adults of D. longicaudata to strains of EPF (Metarhizium robertsii strain V3-160 and M. anisopliae strain MAAP1). We also evaluated the infection of these two fungi on A. ludens larvae parasitized by D. longicaudata. Finally, we determined sub-lethal effects on adults of D. longicaudata that emerged from larvae that had been exposed to low concentrations of M. robertsii. Both fungi caused moderate mortality to D. longicaudata adults. There were no adverse effects on the longevity of parasitoids that emerged from parasitized larvae exposed to M. robertsii. Based on these results, we argue that M. robertsii has the potential to be used for biocontrol of A. ludens, with limited risk to D. longicaudata adults.

Occurrence, Identification, and Virulence of Native Fungal Pathogens Isolated From Mexican Fruit Fly (Diptera: Tephritidae) Larvae From Soils of Three Cropping Systems.

The Mexican fruit fly, Anastrepha ludens Loew, is a significant pest in mango and citrus production areas of Mexico. In this study, we evaluated the effects of some geographic characteristics, rainfall period, soil micro-environmental, and soil coverage variables on the occurrence of entomopathogenic fungi (EPF) associated with A. ludens larvae in soils of mango, grapefruit and mixed crops in central Veracruz state, Mexico. EPF isolates were characterized morphologically and identified by sequence analysis of elongation factor (EF1-1018F, EF1-1620R). We recorded four species of EPF (Metarhizium robertsii J.F. Bisch, S.A. Rehner & Humber [Hypocreales: Cordycipitaceae], M. brunneum Petch [Hypocreales: Cordycipitaceae], M. pinghaense Q.T. Chen & H.L. Guo [Hypocreales: Cordycipitaceae], and Beauveria bassiana (Balsamo) Vuillemin [Hypocreales: Cordycipitaceae]), of which Metarhizium robertsii was the most abundant and the most virulent. Also, we found that rainfall period, organic matter, coverage of herbs and forbs, and calcium levels modulated EPF occurrence. We estimated lethal concentrations for A. ludens larvae of the four most promising isolates, V3-123, V3-160, V1-332, and V3-369. Our results suggest that M. robertsii obtained from agricultural soils holds potential as a biological control agent for A. ludens.

What Has Been the Focus of Sugarcane Research? A Bibliometric Overview.

Sugarcane is one of the main crops worldwide, and it has an important impact on environmental issues. A bibliometric mapping analysis of the research on sugarcane was carried out, using data on the titles, abstracts, and keywords of articles published in leading journals and other peer-reviewed documents available in the SCOPUS database from 1858 to 2019 (27 August), and this was subsequently analyzed with the software VOSviewer. The three most important countries that publish research and were most-cited regarding sugarcane were Brazil, the USA, and India. The analysis of the co-occurrence of terms shows that the main research areas were sugarcane bagasse and terms related to bioenergy, and on a second level of relevance agronomy topics related to increasing crop yields. This first attempt to visualize the abundance of publications regarding sugarcane in their totality is in itself a good starting point for further scientific discussion.

Microstructure and physical changes in the Mexican cooked lamb meat barbacoa made with chilled and frozen meat.

Longissimus dorci (LD) samples of different origin (imported and domestic) with pre-treatments (imported meat stored at -18°C for 6months, domestic meat stored at -18°C for 10days, and domestic meat stored at 4°C for 24h) were cooked as barbacoa and frozen using two treatments (air blast and liquid immersion) and then evaluated after 30days of storage. The results showed that the origin and pre-treatment of meat affected L*, a*, instrumental texture and microstructure; that the storage time affected pH, aw, b* and microstructure; and that the freezing treatments did not affect the meat. Overall, the frozen cooked lamb dish barbacoa could present some problems at the conservation stage due to an increase in pH, aw and changes in microstructure; however, the physical traits (color and texture) remained mostly unchanged and depended more on the quality of the raw meat.

Análisis de la variación intraespecífica de Conidiobolus coronatus usando RAPD y secuencias ITS / Intraspecific variation analysis of Conidiobolus coronatus using RAPD and ITS sequencing

Introducción El hongo Conidiobolus coronatus (C. coronatus) tiene una extensa distribución de hábitats y organismos; se encuentra en forma saprófita, ataca insectos y mamíferos, incluido el humano, aunque de este los reportes son pocos y están restringidos a zonas tropicales. El objetivo de este trabajo fue determinar si existe o no variación genética entre aislamientos de C. coronatus provenientes de lesiones en humanos y otras fuentes. Métodos Once aislamientos de C. coronatus obtenidos de suelo, insectos y humanos se analizaron con las técnicas de polimorfismo derivado de la amplificación aleatoria de ADN (RAPD) y secuenciación del espaciador interno transcrito (ITS1-5.8S rADN-ITS2); para el análisis de las regiones ITS se usaron los métodos de máxima parsimonia, neighbour-joining (NJ) y mínima evolución. Resultados El análisis de los polimorfismos de C. coronatus con las técnicas RAPD e ITS evidenció altos niveles de variación intraespecífica en los aislamientos evaluados. Los aislamientos obtenidos de lesiones en humanos presentan la mayor divergencia genética respecto de los obtenidos de otras fuentes; la mayor distancia genética entre grupos de aislamientos se da entre los provenientes de humanos y los tomados del insecto Lycoriella ingenua. Conclusiones Este trabajo es el primero en evaluar y demostrar que existe variación intraespecífica a nivel molecular de C. coronatus que, a su vez, está relacionada con la fuente de la que se obtuvieron (AU)

Introduction The fungus Conidiobolus coronatus (C. coronatus) has an extensive distribution of habitats and hosts. It is found saprophytically, and attacks insects and mammals, including humans. Although there are few reports on humans, and they are restricted to tropical areas. The aim of this work was to determine whether genetic variation exists between C. coronatus isolates coming from human lesions and other sources. Methods A total of 11 C. coronatus isolates obtained from soil, insects and humans were analyzed with the random amplification of polymorphic ADN (RAPD) and internal transcribed spacer (ITS) techniques; the maximum parsimony, neighbour-joining and minimum evolution methods were used for the ITS analysis. Results The analysis of the C. coronatus polymorphisms showed high intra-species variation levels between the evaluated isolates. The isolates coming from human lesions showed the greatest genetic divergence compared with the remaining isolates. The greatest genetic distance between isolate groups was found between those coming from humans and those taken from the insect Lycoriella ingenua. Conclusions This is the very first work evaluating and demonstrating that within species variation exists at molecular level in C. coronatus, and is related to the source where the isolates were taken from (AU)

[Intraspecific variation analysis of Conidiobolus coronatus using RAPD and ITS sequencing]. / Análisis de la variación intraespecífica de Conidiobolus coronatus usando RAPD y secuencias ITS.

INTRODUCTION: The fungus Conidiobolus coronatus (C. coronatus) has an extensive distribution of habitats and hosts. It is found saprophytically, and attacks insects and mammals, including humans. Although there are few reports on humans, and they are restricted to tropical areas. The aim of this work was to determine whether genetic variation exists between C. coronatus isolates coming from human lesions and other sources. METHODS: A total of 11C. coronatus isolates obtained from soil, insects and humans were analyzed with the random amplification of polymorphic ADN (RAPD) and internal transcribed spacer (ITS) techniques; the maximum parsimony, neighbour-joining and minimum evolution methods were used for the ITS analysis. RESULTS: The analysis of the C. coronatus polymorphisms showed high intra-species variation levels between the evaluated isolates. The isolates coming from human lesions showed the greatest genetic divergence compared with the remaining isolates. The greatest genetic distance between isolate groups was found between those coming from humans and those taken from the insect Lycoriella ingenua. CONCLUSIONS: This is the very first work evaluating and demonstrating that within species variation exists at molecular level in C. coronatus, and is related to the source where the isolates were taken from.

Inhibición in vitro de aislamientos nativos de Trichoderma en presencia de la cepa comercial T22 / In vitro inhibition from native isolates of Trichoderma against commercial strain T22

El objetivo de este trabajo fue evaluar 14 aislamientos nativos del género Trichoderma (Tn) obtenidos de la rizósfera del cultivo de caña de azúcar de acuerdo con su efecto de inhibición in vitro en cultivos duales contra la cepa comercial de Trichoderma harzianum (T22). Los aislamientos nativos con mayor índice de inhibición fueron los denominados Palma (T12) y Hubero (T11), con un valor de 2, mientras que T01, T04, T05 y T08 presentaron un valor de 1. Además, el mayor porcentaje de inhibición fue causado por el aislamiento T03, con una media de 92.32 ± 2.64%, sin diferencias estadísticas con los nativos T07, con un valor inhibición de 88.99 ± 1.46%, T01 87.93 ± 2.28%, y T12; 87.71 ± 3.16. En este caso, los aislamientos T07 y T12 mostraron capacidad inhibitoria con mayores atributos para su selección como agentes de control biológico. Al evaluar la tolerancia in vitro de los aislamientos nativos de Trichoderma a la actividad del agua (aw), se observó efecto significativo sobre el desarrollo micelial de los aislamientos de Trichoderma nativo evaluados. Los aislamientos T03 (7919.3 ± 932.53) y T12 (6388.2 ± 623.40) presentaron el mejor desarrollo radial. Estos resultados sugieren que los aislamientos T03 y T12 podrían desarrollarse mejor bajo condiciones de estrés hídrico. Por lo anterior, concluimos que los aislamientos T07 y T12, son los mejores candidatos como agentes inhibidores y se sugiere evaluarlos in vitro o invernadero contra el agente causal de la enfermedad del muermo rojo en caña de azúcar (Colletotrichum falcatum).

The objective of this work was to evaluate 14 native e Trichoderma genus isolates (Tn) obtained from the rhyzosphere of sugarcane plantations in accordance with their inhibitory in vitro effect on dual cultures against a commercial strain of Trichoderma harzianum (T22 strain). The native isolates with the highest inhibition levels were the named Palma (T12) and Hubero (T11), with a type value 2, although the T01, T04, T05 and T08 presented activity type 1. The highest percentage of inhibition of the strain T22 was caused by the isolate T03 (average of 92.32 ± 2.64%), with no statistical difference (P >0.05) from the natives isolates T07 (inhibition average of the 88.99 ± 1.46%), T01 (average 87.93 ± 2.28%), and T12 (average 87.71 ± 3.16%). In this case, T07 and T12 isolates showed inhibitory capacity in more attributes for selection as biological control agents. In assessing tolerance in vitro native isolates of Trichoderma to water activity (aw), we observed significant effect on mycelia growth of native Trichoderma isolates evaluated. In addition, isolates T03 (average 7919.3 ± 932.53) and T12 (average 6388.2 ± 623.40) had the best radial development. These results suggest that the isolates T03 and T12 could develop better under water stress conditions. Therefore, we conclude that the isolates T07 and T12 are the best candidates as inhibitory agents and we suggest evaluating under in vitro condition or in greenhouse against with the causal agent of the red rot disease from the sugarcane (Colletotrichum falcatum).