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Leafcutter ants (Atta spp.) are one of the mos t economically harmful pests in agriculture, considered dominant in the Neotropics and South America. Mature colonies of A. mexicana have a great economic impact on Mexico's agriculture. Microbial agents in the form of biopesticides are an effective component of integrated pest management (IPM) strategies and may present a better alternative to synthetic insecticides. Among the fungi most used as biological insecticides there are Beauveria bassiana and Metarhizium anisopliae. The objective of this research was to evaluate the effect of the entomopathogenic fungi B. bassiana and M. anisopliae of commercial origin and a native strain of B. bassiana from México (MA-Bb1) on adults of Atta mexicana under controlled conditions. In the bioassay, five formulations and a control group were tested (B. bassiana MA-Bb1, B. bassiana MA-Bb1+ Diatomin®, B. bassiana®, M. anisopliae®, Diatomin®, and Tween 80 (0.01%). The MA-Bb1+ Diatomin® biopreparation induced the highest mortality (100%) in four-week-old A. mexicana, followed by the MA-Bb1, M. anisopliae®, and B. bassiana® biopreparations, which caused mortality of 83.33%, 73.98%, and 68.70%, respectively. Treatments containing B. bassiana and M. anisopliae were efficient in controlling A. mexicana under controlled conditions. The most efficient biological control was achieved with the B. bassiana fungus and Diatomin®, which presented the highest total death rate in A. mexicana 96 h post infection, in contrast to the control group (Tween 80), which attained the lowest speed of death in the present investigation. [ABSTRACT FROM AUTHOR]

Featured Application: Based on our results, the studied edible resources may be included in the local eat-well plate through diets to ameliorate some disorders of the metabolic syndrome. Herein, we present an integrative investigation of the nutritional and nutraceutical potential of Lactarius indigo, Clitocybe nuda, Clitocybe subclavipes, Russula delica, Russula brevipes, Clitocybe squamulosa, and Amanita jacksonii, which are edible mushrooms consumed in the northeastern highlands of Puebla, Mexico. The content of protein oscillated from 4.8 to 10.9 g 100 g−1 fresh weight (FW) whereas that of fiber ranged from 8.8 to 19.7 g 100 g−1 FW. The edible species presented low amounts of fat (1.5–3.4 g 100 g−1 FW) and reducing sugars (0.8–2.9 g 100 g−1 FW), whereas the content of vitamin C oscillated from 6.5 to 84.8 mg 100 g−1 dry weight (DW). In addition, four vitamins of B complex (thiamine, riboflavin, vitamin B6, and folate) were determined in different concentrations. A high abundance of potassium (92.3–294.3 mg 100 g−1 DW), calcium (139.1–446.9 mg 100 g−1 DW), and magnesium (81.3–339.1 mg 100 g−1 DW) was determined in most of the edible mushrooms, as well as detectable levels of p-hydroxybenzoic acid (2.2–48.7 mg 100 g−1 DW), protocatechuic acid (0.5–50.8 mg 100 g−1 DW), oleic acid (14.2–98.3 mg 100 g−1 DW), linoleic acid (748–1549.6 mg 100 g−1 DW), and linolenic acid (from 9.1 to 83.6 mg 100 g−1 DW). The total phenol content and antioxidant capacity significantly (p < 0.05) varied among the studied species, and their capacity to inhibit enzymes involved in glucose, lipid, and polyamine metabolism. Nevertheless, the hydroalcoholic extracts from A. jacksonii and L. indigo efficiently inhibited alpha-glucosidase and ornithine decarboxylase (IC50 < 50 µg mL−1), respectively. The evaluation of the same extracts on microorganisms associated with the gastrointestinal tract showed negligible toxicity on probiotics (MIC > 500 µg mL−1) and moderate toxicity against pathogenic bacteria (MIC < 400 µg mL−1). Based on the studied parameters, principal component analysis and orthogonal partial least squares discriminant analysis clustered these edible mushrooms into two main groups with similar biological or chemical properties. [ABSTRACT FROM AUTHOR]

There are several by-products obtained in agricultural systems that can contribute to small-scale production systems within backyards, in this sense, the production of oyster mushrooms (Pleurotus ostreatus) has been integrated into the rural family economy in Mexico. After harvesting the fruiting bodies, the remainder is known as sold-out substrate, this by-product has been destined for other agricultural uses such as: medium for seedlings, vermiculture or fertilizer; however, there are studies where it has been used in the diet of bovine cattle. In this study, the effects of sold-out substrate (corn stubble) of P. ostreatus in the diet of broilers with different percentages of protein, on feed conversion ratio, carcass yield, and broiler meat quality were evaluated. A total of 120 broilers Ross 308 were randomly assigned in 12 pens with concrete floor and curly shaving with an area of 3 m2. During the initial period (1 to 28 days), all broilers were fed commercial feed® mixture. On day 29, the broilers were weighed and divided into four treatment groups and fed diets with different percentages of protein until the end of the experiment. Feed conversion ratio was significantly higher in treatment control (TC) compared to the other treatments; however, the performance parameters were not affected by the diet supplemented with sold-out substrate, likewise, the color and quality of the meat were in a normal range (48 < L* < 51) and with a good amount of crude protein. Sold-out substrate of P. ostreatus from corn stubble presented a high mineral content of Mg, Na, K, Fe, Cu, and Mn suitable to be considered in diets for feeding backyard broilers. [ABSTRACT FROM AUTHOR]

Phaseolus vulgaris is the most legume cultivated in the world; in Mexico, it is considered the second most important crop after corn. The aim of this research was to determine the characteristics of Xanthomonas campestris strain "Xcf1-APJR" isolated from the leaves of bean crops, and determine the antimicrobial activity of cinnabarin on this strain. Bacterial cultures were obtained from leaves with necrotic leaf spot symptoms of bean plant variety "Flor de Mayo M38" in Puebla, Mexico. The antimicrobial activity of cinnabarin was tested at 7, 14 and 21 days on X. campestris pv. campestris. The Xcf1-APJR strain showed 100% identity with X. campestris pv. campestris as a causal agent of necrotic leaf spot. Treatment with a potato dextrose medium with a dehydrated sugar cane (PDA+C) showed a higher orange pigmentation than the other treatments after 7, 14 and 21 days of incubation and a higher concentration of cinnabarin (54.33 InU/g) with in vitro antimicrobial activity against X. campestris pv. campestris. [ABSTRACT FROM AUTHOR]

Featured Application: The synthesis of the nutraceutical resveratrol by filamentous fungi represents a new and exciting area for bioprocess research. Considering that resveratrol was initially placed as a natural phytoalexin from plants, its biosynthesis by fungi may be regulated by several factors including a broad spectrum of small molecules and enzymes involved in chemical defense. This work reports on the effect of some elicitors that promote resveratrol biosynthesis in fungi and how they can be used to produce this stilbene under controlled conditions. The chemical factors that regulate the synthesis of resveratrol (RV) in filamentous fungi are still unknown. This work reports on the RV production by Arcopilus aureus MaC7A under controlled conditions and the effect of amino acid precursors (PHE and TYR), monoterpenes (limonone, camphor, citral, thymol, menthol), and mixtures of hydrolytic enzymes (Glucanex) as elicitors for boosting fungal RV. Batch cultures with variable concentrations of PHE and TYR (50–500 mg L−1) stimulated RV production from 127.9 ± 4.6 to 221.8 ± 5.2 mg L−1 in basic cultures developed in PDB (pH 7) added with 10 g L−1 peptone at 30 °C. Maximum levels of RV and biomass were maintained during days 6–8 under these conditions, whereas a dramatic RV decrease was observed from days 10–12 without any loss of biomass. Among the tested volatiles, citral (50 mg L−1) enhanced RV production until 187.8 ± 2.2 mg L−1 in basic cultures, but better results were obtained with Glucanex (100 mg L−1; 198.3 ± 7.6 mg L−1 RV). Optimized batch cultures containing TYR (200 mg L−1), citral (50 mg L−1), thymol (50 mg L−1), and Glucanex (100 mg L−1) produced up to 237.6 ± 4.7 mg L−1 of RV. Our results suggest that low concentrations of volatiles and mixtures of isoenzymes with β-1, 3 glucanase activity increase the biosynthesis of fungal RV produced by A. aureus MaC7A in batch cultures. [ABSTRACT FROM AUTHOR]

Featured Application: This work was focused in the generation of six yeast lines able to produce resveratrol from p-coumaric acid. Industrial use of these strains may be contemplated. Resveratrol is a nutraceutical with relevant benefits to human health. This investigation reports on the generation and evaluation of six recombinant yeast lines that produce resveratrol from p-coumaric acid. The yeast lines contained a single p-coumaric acid-Co-A ligase from Plagiochasma appendiculatum combined with the stilbene synthases from Parthenocissus henryana, Polygonum cuspidatum, Morus alba var. atropurpurea, Rheum tataricum, Vitis vinifera and Arachis hypogaea. Codon optimized versions of these sequences were inserted in an expression vector flanked by the constitutive PGK and GPD promoters before expression in Saccharomyces cerevisiae. Batch fermentation (60 h) revealed that yeast lines had different capacities (p < 0.01) to produce resveratrol. Slightly acidic pH (6) and concentrations <100 mg L−1p-coumaric acid improved resveratrol yields. Among the six lines, those containing the stilbene synthases (STS) from P. cuspidatum and M. alba produced up to 39 mg L−1 using 70 mg L−1p-coumaric acid. On the other hand, lines expressing STS from V. vinifera, A. hypogaea and R. tataricum generated resveratrol faster than other lines but accumulated lower amounts at the end of the batch period (27–30 mg L−1). The simultaneous consumption of ethanol and p-coumaric acid corroborates the role of ethanol as a carbon source involved in the conversion of p-coumaric acid into resveratrol. [ABSTRACT FROM AUTHOR]