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Little is known on the use of biodegradable films for the control of diseases in crops of agricultural importance. Consequently, the objective of this work was to determine the efficacy of chitosan hybrid films impregnated with thyme essential oil on Hass avocado fruits previously infected with Fusarium solani isolated from the northeastern highlands of Puebla, Mexico. The native strain of F. solani was morphologically and molecularly identified and the fungistatic activity of three chitosan films supplemented with 0.7% (FT1), 1.0% (FT2) and 1.3% (FT3) of thyme essential oil was evaluated in situ on the growth of F. solani in avocado fruits. Texture, transmittance and opacity of the films were obtained by scanning electron microscopy and UV-Vis spectrometry, respectively. Overall, it was recorded that films with a higher concentration of thyme essential oil (1-1.3% w/v) presented lower transmittance in the UV light range and higher opacity. Avocado fruits infected with F. solani simultaneously treated with FT2 and FT3 reduced the appearance of symptoms while preserved firmness, as well as fiber, fat, reducing sugars, and protein content (p < 0.01). In the same context, these materials promoted the conservation of the content of the nutraceuticals linoleic acid, oleic acid, palmitic acid and palmitoleic acid for 21 days. These results suggest that the hybrid films generated in the present study have the ability to control fusariosis caused by this fungus, prolonging the shelf life of Hass avocado fruit. [ABSTRACT FROM AUTHOR]

The Tehuacán-Cuicatlán Biosphere Reserve in México holds genetic richness and endemism for the genus Jatropha, but the specific use of the plants and the seed chemical profiles are still unknown. We recorded the traditional forms of use of Jatropha species, and analyzed the chemical composition of Jatropha spp. seeds. For this, a semi-structured survey was conducted in 15 towns, and 20 interviews were applied in each one between May and August 2012 to estimate the Significant Use Level and Relative Use Value per species. Besides, seeds from J. neopauciflora, J. rufescens, and J. rzedowskii were collected between August and October 2013, and to seed flour samples we determined total lipids by the Soxhlet method, crude protein by the Kjendahl method, and ashes according to AOAC methods; fatty acid profile and phorbol esters were determined by gas chromatography and by HPLC, respectively. The species J. neopauciflora, J. oaxacana, J. rufescens, J. ciliata, and J. rzedowskii, are used as traditional medicine, food, and ornaments, except for J. ciliata, for which none use was recorded. The Significant Use Level as food was found not significant, but for medicinal purposes, J. neopauciflora obtained the highest Relative Use Value (9.0 %). The latex is used to treat 13 disorders, including dental problems and oral diseases with a Significant Use Level of 32.9 %; it is also used as a hemostatic. The protein content among species varied from 23.37 to 26.06 %, and total lipids from 34.79 to 36.60 %. The principal unsaturated fatty acids were oleic (25.08 to 30.09 %) and linoleic (44.55 to 48.46 %), and the saturated fatty acids were palmitic (10.11 to 16.50 %) and stearic (9.47 to 11.15 %). Phorbol esters, the main cause of seed's toxicity, were absent in J. neopauciflora, J. rufescens, and J. rzedowskii. In conclusion, the Significant Use Level of Jatropha species studied was low, with little cultural acceptance and sporadic utilization. The Relative Use Value was important for medicinal purposes, especially for J. neopauciflora. The dehulled seeds of J. neopauciflora, J. rufescens, and J. rzedowskii are potentially useful as food, having high protein contents, and unsaturated oleic and linoleic fatty acids. With this study we report three non-toxic Jatropha species and recommend to scientifically validate the antimycotic use of J. neopauciflora latex. Rev. Biol. Trop. 66(1): 266-279. Epub 2018 March 01. [ABSTRACT FROM AUTHOR]

The effect of feeding with protected fats on double purpose cows. The objective of this study was to determine the reduction of post-partum anestrum in cows by supplying protected fats. The study was conducted ad the Experimental field La Posta, Paso del Toro, Veracruz, México. The cows were randomly assigned to two groups: supplementation with protected fats (GP; T1, n= 20) or tallow (SGP; T2, n=20) at 2.7% of a dry weight-based diet. Milk production, physical condition (CC), progesterone and tiroid hormone levels were registered. (T3 and T4). Sources of variation were diet, genetic group and number of calf births, and the dependent variables PL were days to the fi rst estrus (DPE), CC and meatabolite levels. Correlations among variables were conducted. No effect (p>0,05) of treatments on milk production were observed, but signifi cant effects (p<0,01) for the fist corpus luteum. Physical condition 4,5 had the best milk production (p<0,01; 16,68±1,076 L/day) and lower number of days to the first estrum (p<0,05; 31,71±7,5 d). Tiroid hormones did not show differences (p>0,05) among treatments: T1= 72,4 and T2 = 72,72 ug/dl. Insuline was higher (p<0,05) in T2 (6,87 UI) than in T1 (5,26 UI). It is concluded that the type of fat did not affect milk production but stimulated the resumption of ovarian activity and reduced the concentration of insulin in the serum. [ABSTRACT FROM AUTHOR]

Fungal metabolites are promising alternatives for the development of biorational pesticides. In this sense, microfungi from tropical regions are valuable sources of natural compounds for pest management. With the aim of broadening the search for new eco-friendly products to manage plant pests, this study was carried out to evaluate the biological activity of 23 tropical fungal extracts on three species of phytophagous insects and a plant parasitic nematode. In addition, the active principles of the most effective extract were identified. The insect deterrent activity of fungal extracts was evaluated on the settling of aphids Myzus persicae and Rhopalosiphum padi, and on the feeding of lepidoptera larva Spodoptera littoralis; the nematostatic activity was evaluated on the mobility of Meloidogyne javanica. Active metabolites from Gliomastix masseei were identified by GC-MS techniques and by comparison with commercial standards. Results showed seven extracts with strong effect on the settling of M. persicae and R. padi (settling inhibition >80%). The calculated median of effective concentration (EC 50 ) values ranged from 8 to 38μg/cm 2 for the extracts of Clonostachys rosea and G. masseei, respectively. Bioassay-guided separation of the ethyl acetate extract of G. masseei revealed the presence of fatty acids and their derivatives, where methyl 9-octadecenoate was the most active compound with EC 50 values of 16μg and 35μg/cm 2 for M. persicae and R. padi, respectively. Extracts of C. rosea and G. masseei could be a promising option in the control of pest aphids in agriculture., (Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)