Scientia Agropecuaria

**Efecto de la harina de hojas de Erythrina sp. sobre el perfil bioquímico, parámetros biológicos e histopatología del hígado de Cavia porcellus**

El objetivo de este estudio fue determinar el efecto de la harina de hojas de Erythrina sobre los perfiles bioquímicos, parámetros biológicos y tejido hepático de Cavia porcellus. Se utilizaron 75 cuyes machos de 13 días de edad, formándose 5 grupos experimentales con tres repeticiones cada uno. Todos se alimentaron con 100 g/día de King grass y alimento balanceado para cuyes ad libitum. Las hojas con peciolo se secaron y se molturaron a 1 mm de diámetro. La sangre se obtuvo a los 75 días de edad de la vena safena lateral y en suero sanguíneo se determinó perfiles de glucosa, proteína total, albumina, aspartato aminotrasferasa, alanino aminotransferasa, lactato deshidrogenasa y urea. Trozos de hígado se procesaron hasta obtener los cortes histológicos. Los perfiles de proteína total y albumina mostraron regresión lineal positiva (p < 0,05), el rendimiento de carcasa regresión lineal negativa (p < 0,05) y la estructura histológica del hígado no tuvo cambios a medida que incrementó el nivel de harina de Erytrhina en la ración. La Erythrina causó una respuesta contrastante entre los perfiles de proteína total y albumina en sangre y el rendimiento de carcasa y no causó alteración estructural del hígado

The aim of this research was to determine the effect of Erythrine leaves powder on serum biochemical profiles, biological parameters and liver histopathology of Cavia porcellus. 75 thirteen days old male guinea pig distributed in five groups with three replicates each were used. All groups were fed with 100 g/day of king grass and balanced diet ad libitum. Erythrine leaves including petiole were dried, grounded to 1 mm diameter and added to the diet. Blood was obtained from the lateral saphenous vein and in blood serum was measured glucose, total protein, albumin, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and urea. Liver tissue were processed and stained with hematoxylin and eosin. A positive linear regression in the total protein and albumin (p < 0.05) and a negative linear regression for carcasses (p < 0.05) perfomance and no changes in the liver histologic morphology in relation to the increase of Erythrin leaves flour in the diet were shown. Erythrina caused a contrasting response between total protein and albumin profiles in blood and carcass yield and did not cause structural alteration of the liver

**Identificación de parásitos en paiches "Arapaima gigas" juveniles**

El objetivo de este estudio fue identificar parasitosis en paiches juveniles "Arapaima gigas", criados en cautiverio en el instituto de Investigaciones de la Amazonia Peruana (IIAP-Ucayali) Perú. En una población de 190 juveniles se tomó una muestra al azar de 50 ejemplares de 2,5 años de edad. La técnica de evaluación fue visual-directa y microscópica. Se identificaron 5 ectoparásitos: Trichodina sp. (Protozoario ciliado), Dolosp sp. (Crustáceo), Dawestrema cycloancistrium (Monogeneo), Dawestrema cycloancistroides (Monogeneo) y Placobdella sp. (Sanguijuela); se encontraron 3 endoparásitos: Nilonema senticosum (Nemátodo), Caballerotrema sp. (Tremátodo) y Gymnodinium sp. (Protozoario flagelado); no se identificaron hemoparásitos en los frotis sanguíneos. Los parásitos se localizaron en los siguientes órganos: filamentos branquiales (Trichodina sp. Dawestrema cycloancistrium y Dawestrema cycloancistroides), piel y aletas (Trichodina sp., Placobdella sp. y Dolosp sp.), vejiga aerífera o seudo pulmón (Nilonema senticosum), intestino (Caballerotrema sp.) y estómago (Gymnodinium sp.).

The aim of this research was to identify parasitosis in juvenile paiches "Arapaima gigas", raised in captivity at the Peruvian Amazon Research Institute (IIAP-Ucayali), Peru. In a population of 190 juveniles, a random sample of 50 individuals of 2.5 years of age was taken. The evaluation technique was visual-direct and microscopic. 5 ectoparasites were identified: Trichodina sp. (Protozoan cilia), Dolosp sp. (Crustacean), Dawestrema cycloancistrium (Monogeneo), Dawestrema cycloancistroides (Monogeneo) and Placobdella sp. (Leech); 3 endoparasites were found: Nilonema senticosum (Nemátodo), Caballerotrema sp. (Tremátodo) and Gymnodinium sp. (Protozoario flagellate); no hemoparasites were identified in the blood smears. Parasites were found in the following organs: gill filaments (Trichodina sp. Dawestrema cycloancistrium and Dawestrema cycloancistroides), skin and fins (Trichodina sp., Placobdella sp. and Dolosp sp.), aerial bladder or pseudo lung (Nilonema senticosum), intestine (Caballerotrema sp.) and stomach (Gymnodinium sp.).

**Development of functional cookies with wheat flour, banana flour (Musa paradisiaca ), sesame seeds (Sesamum indicum ) and storage stability**

Functional cookies were developed using banana flour (BF) and sesame seeds (SS). Protein, moisture and ash were determined, and farinographic analyzes of flours were performed. The attributes odor, color, flavor, crunch and the IC50 value of the cookies were determined. The results were evaluated with the Complete Randomized Design and the Tukey and Kruskall Wallis test. The flour mixture presented higher protein (10.2%), humidity (14.40%) than BF, but lower than wheat flour. Cookies with 10%, 15% and 20% BF and 8% sesame seeds were selected. Flours with 10%, 15% and 20% BF had similar values of water absorption (≤ 60%) and different values statistically (p ≤ 0.05) for development time, mass stability and degree of softening. Cookies with 20% BF and 8% SS (SC) had IC50 = 17.52 ± 0.25 mg / mL, with moisture, protein, fat, crude fiber, ash and carbohydrates of 1.88%, 10.65%, 22.01%, 1.01%, 1.54% and 62.91%, respectively. SC did not present sensorial statistical differences (p ≤ 0.05) the first two months, the third month decreased the acceptability of the crunch and flavor. In ninety days of storage the IC50 value (29.07 ± 0.92 mg / mL), reducing sugars (1.20 ± 0.02) and pH (5.24 ± 0.01) decreased and humidity (3.83 ± 0.03) increased.

Aislamiento, propagación y crecimiento de hongos comestibles nativos en residuos agroindustriales

La investigación tuvo como objetivo aislar el micelio secundario de Auricularia spp y Pleurotus spp procedente de tres áreas naturales de la región San Martín, así como evaluar el crecimiento en medio agar papa dextrosa y en sustratos estériles a base de residuos agroindustriales. Se obtuvieron 10 aislamientos de micelios secundarios a través de carpóforos desinfectados de Pleurotus spp y otros 10 aislamientos de carpóforos desinfectados de Auricularia spp. La mayor velocidad de crecimiento en Auricularia spp fue de 62,5 µm h-1 (A1) y de 75 µm h-1 (B10) para Pleurotus spp. En una segunda parte del experimento se produjo semilla de las cepas nativas más veloces en granos de maíz esterilizado durante un periodo de incubación de 40 días. La semilla fue inoculada en sustratos estériles a base de residuos agroindustriales. Las cepas A1 de Auricularia spp y B10 de Pleurotus spp desarrollaron mejor en sustrato a base de residuos de pulpa de café, logrando una eficiencia biológica de 30,33% y 18,20%, respectivamente. Se concluye que las cepas nativas A1 y B10 de hongos comestibles pueden ser utilizadas en la propagación de semilla y producción de hongos comestibles, brindando al agricultor una alternativa complementaria de alto valor nutritivo.

The objective of the research was to isolate the secondary mycelium of Auricularia spp and Pleurotus spp from three natural areas of the San Martín region, as well as to evaluate the growth in agar potato dextrose medium and in sterile substrates based on agro industrial residues. Ten isolates of secondary mycelia were obtained through disinfected carpophores of Pleurotus spp and another 10 isolates of disinfected carpophores of Auricularia spp. The highest growth rate in Auricularia spp was 62,5 µm h-1 (A1) and 75 µm h-1 (B10) for Pleurotus spp. In a second part of the experiment, seed of the fastest strains was produced in sterilized maize grains during a 40-day incubation period. The seed was inoculated into sterile substrates based on agro industrial residues. The native strains A1 of Auricularia spp and B10 of Pleurotus spp developed better in substrate based on coffee pulp residues, achieving a biological efficiency of 30.33% and 18.20%, respectively. It is concluded that the native strains A1 and B10 of edible fungi can be used in seed propagation and edible fungus production, providing the farmer with complementary food of high nutritional value.

PCR en tiempo real para el sexaje y análisis citológico de la sinapsis del bivalente más pequeño en espermatocitos en paquiteno de Oreochromis niloticus

El objetivo de la presente investigación fue dar a conocer nuevos marcadores moleculares para la PCR en tiempo real asociados a los cromosomas sexuales y el análisis de la sinapsis del bivalente más pequeño en espermatocitos en paquiteno de Oreochromis niloticus. Se diseñaron cuatro pares de cebadores y se pusieron a prueba por PCR punto final y por PCR en tiempo real utilizando el fluorescente SYBR® Green en muestras de ADN de hembras XX, machos XY y supermachos YY. Los tamaños de los fragmentos amplificados por PCR punto final fueron concordantes a los valores esperados y por PCR en tiempo real se demostró igual especificidad pero con ventaja en rapidez en la detección de amplificación de marcadores asociados a los cromosoma X y Y, de acuerdo con las condiciones de la PCR establecidas. Las diferencias genéticas entre las regiones de los cromosomas X y Y demostradas con los marcadores específicos no fueron perceptibles citológicamente en los espermatocitos en paquiteno de O. niloticus XY. En base a las diferencias y homologías de las secuencias de ADN entre las accesiones KC710223 y KC710224 de los cromosomas X y Y se propone un modelo de sinapsis del bivalente XY.

The aim of the present study was to report new molecular markers for real-time PCR associated with X and Y sex chromosomes, and perform analysis of the synapsis of the smallest bivalent in pachytene spermatocytes of XY male Oreochromis niloticus. Four pairs of primers were designed and were tested by endpoint PCR and real-time PCR using SYBR Green detection system in DNA samples from XX females, XY males and YY supermales. In order to assess the smallest bivalent synapsis, testicular samples from XY males were used to make chromosomal spreads in pachytene. Size range of fragments amplified by endpoint PCR was concordant with the expected values. Real-time PCR assay showed equal specificity but speed advantage in amplification detection of markers associated with X and Y chromosomes according to the established PCR conditions. Genetic differences between regions of the X and Y chromosomes (smallest bivalent) proven with specific markers were not cytological perceptible in pachytene spermatocytes from XY O. niloticus. A model of XY bivalent synapse was suggested based on the DNA sequences homologies and differences between KC710223 and KC710224 accessions from X and Y chromosomes.

YY super males have better spermatic quality than XY males in red tilapia Oreochromis niloticus

The influence of sex-related chromosomal arrangement in an YY and XY population of Oreochromis niloticus males was investigated in this study. A better spermatic mobility, motility, viability, confluence and less abnormality were found in double Y-chromosome males (YY-males), compared to XY-males; however, this better spermatic quality did not correlate with the body weight of individuals which was significantly better in XY-males. This study establishes the influence of YY-related sequences over spermatic quality and indicates the usefulness of the YY technology as a strategy to obtain better fish breeders and genetically male individuals for a tilapia farming program.

**Impacto del abonamiento integral en el rendimiento y calidad de fresa (Fragaria x ananassa Duch.) cv. Selva bajo sistema de riego por goteo y cobertura plástica**

El objetivo de la investigación fue determinar el efecto del abonamiento integral en la calidad y rendimiento de fresa cv. Selva, su incidencia en la tasa de respiración y fertilidad del suelo; se realizó en el fundo Santa Teresa de Cayma, Arequipa Perú. Los tratamientos resultaron de integrar 3 niveles de abonamiento químico: 0%; 50% y 100% de la formulación: 200 N, 60 K2O y 60 P2O5 y 3 niveles de abonamiento orgánico: 0%; 50% y 100% de la formulación: 100 L de Humega, 12 L de Bioflora Phos y 60 L de Bioflora Potash; evaluándose 9 tratamientos con 3 repeticiones, en diseño de bloques completos al azar; con arreglo factorial 3 x 3. No hubo efecto estadístico significativo sobre la calidad de frutos. El tratamiento con 50% de abonamiento químico y 50% orgánico logró el mayor rendimiento de frutos de fresa (17114,63 kg·ha-1) siendo 13,25% de categoría extra; 57,62% de primera; 25,18% de segunda; 2,06% de tercera y 1,90% de descarte. La tasa de respiración y la fertilidad del suelo no mostraron diferencia estadística significativa; excepto a 80 días del trasplante, donde el abonamiento orgánico al 100% incrementó la tasa de respiración.

The objective of the research was to determine the effect of integral fertilization on fruit quality and yield of strawberry cv. Selva, its incidence in the respiration rate and soil fertility; it was carried out in the Santa Teresa farm of Cayma, Arequipa Peru. The treatments resulted from integrating 3 levels of chemical fertilization: 0%; 50% and 100% of the formulation: 200 N, 60 K2O and 60 P2O5 and 3 levels of organic fertilization: 0%; 50% and 100% of the formulation: 100 L of Humega, 12 L of Bioflora Phos and 60 L of Bioflora Potash; evaluating 9 treatments with 3 repetitions, in randomized complete block design with factorial arrangement 3 x 3. There was no significant statistical effect on fruit quality. The treatment with 50% of chemical fertilization and 50% of organic fertilization achieved the highest yield of strawberry fruits (17 114.63 kg · ha-1) being 13.25% of extra category; 57.62% of first; 25.18% of second; 2.06% of third and 1.90% of waste. The respiration rate and soil fertility showed no significant statistical difference; except at 80 days after the transplant, where 100% organic fertilization increased the respiration rate.

Aplicación de modelos cinéticos no estructurados en el modelamiento de la fermentación láctica de subproductos de pesca

En el presente trabajo se evaluaron cinco modelos en su capacidad de predecir la cinética de producción de ácido en la fermentación láctica de sub productos de pesca. Los modelos no estructurados evaluados fueron: Gompertz, Baranyi-Roberts, Özilgen, Peleg y Vasquez-Murado. La evaluación estadística entre modelos comprendió la Suma Cuadrado del Error (SCE), la Prueba de Fisher y los Índices de Sesgo y Precisión de Ross. Los modelos que presentaron menores valores de SCE, ausencia de diferencias significativas entre sí (p < 0,05) y mejores Índices de Sesgo y Precisión fueron el modelo empírico de Gompertz y el modelo mecanicista de Baranyi-Roberts, ello debido a su capacidad de modelar curvas simétricas y asimétricas en el primer caso y a su flexibilidad a diferentes condiciones en el segundo caso. El modelo empírico de Peleg y modelo logístico de Vasquez-Murado no lograron dar un ajuste adecuado para el tipo de fermentación láctica analizada. La diferencia en la capacidad predictiva entre los modelos ensayados se debió a que la fermentación se realizó con un arrancador de dos cepas con diferentes velocidades de producción de ácido láctico, lo que generó una curva de producción de ácido láctico con una asimetría que los modelos de Peleg y Vasquez-Murado no lograron fijar en forma adecuada.

In the present work, five models were evaluated in their ability to predict the kinetics of acid production in the lactic fermentation of sub-fishery products. The non-structured models evaluated were from the Gompertz, Baranyi-Roberts, Özilgen, Peleg and Vasquez-Murado models. Statistical evaluation of models included the Residual Sum of Square (SCE), Fisher's Test and Ross's Bias and Precision Indices. The models that presented lower values of SCE, absence of significant differences between them (p < 0.05) and better Bias and Precision Indices were the empirical models of Gompertz and the mechanistic model of Baranyi-Roberts, due to their ability to model symmetric and asymmetric curves in the first case, and their flexibility to different conditions in the second case. The Peleg empiric model and Vasquez-Murado logistic model failed to provide adequate fit for the type of lactic fermentation analyzed. The difference in the predictive capacity of the tested models was due to the fact that the fermentation was carried out with a starter of two strains with different rates of production of lactic acid, which generated a production curve with an asymmetry that the models of Peleg and Vasquez-Murado failed to fix properly.

**Bocadito con alto contenido proteico: un extruido a partir de quinua (Chenopodium quinoa Willd.), tarwi (Lupinus mutabilis Sweet) y camote (Ipomoea batatas L.)**

La presente investigación tuvo como objetivo la elaboración de un bocadito extruido de elevado tenor proteico, a partir de quinua (Chenopodium quinoa Willd.), tarwi (Lupinus mutabilis Sweet) y fécula de camote (Ipomoea batatas L.). Para su formulación se aplicó el método de diseño de mezclas usando la herramienta computacional estadística Design Expert® versión 7.0, siendo las variables independientes las harinas de quinua, tarwi y fécula de camote; y las variables dependientes el contenido de proteína, índice de expansión, densidad aparente y dureza de los extruidos. La formulación óptima se determinó aplicando la prueba de deseabilidad basada en los modelos de regresión ajustado, dicha formulación se obtuvo maximizando el contenido de proteína e índice de expansión; y minimizando la dureza y densidad aparente de los extruidos. La formulación óptima tuvo un porcentaje de quinua, tarwi y fécula de camote de 57%, 26% y 17 % respectivamente. El análisis fisicoquímico de la fórmula óptima dio como resultado 20,16% de proteína, 2,19 de índice de expansión, 0,220 g/cm3 densidad aparente y 9,31 N de dureza. La calidad proteica de la formulación óptima fue determinada mediante los ensayos de digestibilidad verdadera y valor biológico verdadero en ratas, obteniéndose 83,5% y 62,9% respectivamente

The aim of this research was to elaborate a high-protein extruded snack from quinoa (Chenopodium quinoa Willd.), tarwi (Lupinus mutabilis Sweet) and sweet potato starch (Ipomoea batatas L.). For its formulation, the mixture design method was applied using Design Expert® 7.0 software. Quinoa, tarwi and sweet potato starch were the independent variables and the dependent variables were the protein content, expansion index, bulk density and hardness of the extrudates. The optimal formulation was determined by applying the test of desirability based on adjusted regression models, this formulation was obtained by maximizing the protein content and expansion index, and minimizing the hardness and bulk density of the extrudates. The optimal formulation was obtained from a mixture of quinoa, tarwi and sweet potato starch of 57%, 26%, and 17% respectively. Physicochemical analysis of the optimal formula resulted in 20.16% protein, 2.19 expansion index, 0.220 g/cm3 bulk density and 9.31 N hardness. The protein quality of the optimal formulation was determined by the assays of true protein digestibility and true biological value in rats, obtaining 83.5% and 62.9%, respectively

Are sensory attributes and acceptance influenced by nutritional and health claims of low-sodium salami? Preliminary study with Brazilian consumers

The first contact between consumers and the food product is usually the packaging and its labelling. Therefore, it is the primary means to generate consumers expectations. The aim of the present work was to evaluate the influence of nutritional and health claims on acceptance of salami with reduced sodium content, aimed at finding guidance for the product reformulation. Sixty consumers evaluated four samples of salami. The overall acceptance was evaluated using a nine-point hedonic scale, and the attributes color, tenderness, characteristic flavor and salt content, were evaluated by 7 - point just-about-right (JAR) scale. For the expectation test, overall liking of salami with reduced sodium content was evaluated by consumers under three conditions: (1) blind test (B); (2) expectation generated by nutritional and health claims (E), and (3) consumers re-tasted the salami having the nutrition and health claims available (R). Students t-tests performed on data indicated no significant differences (p > 0.05) between the mean acceptance under the blind (B) and real (R) conditions, although expectation ratings (E) were significantly higher than (B) (p ≤ 0.05). However, linear regression of (R - B) x (E - B) ratings revealed a major assimilation effect of expectation, especially under negative disconfirmation (E > B). Contrast effect was also observed, but to a lesser extent. The results showed that saltiness attribute was not decisive in decreased acceptance according to the JAR scale, but it was relevant in the aftertaste generated by adding salt substitutes. Finally, nutritional and health claims had little effect on consumer acceptance.

**Efecto del aceite esencial de Cymbopogon citratus sobre propiedades fisicoquímicas en películas de quitosano**

Se investigó el efecto de la incorporación de aceite esencial de zacate limón (Cymbopogon citratus), en concentraciones de 0, 200 y 400 ppm, en las propiedades fisicoquímicas (espesor, humedad, solubilidad, permeabilidad al vapor de agua, color, transparencia) y mecánicas (resistencia a la tensión y elongación) de películas de quitosano a dos concentraciones (1 y 3%). Los resultados mostraron un efecto significativo (p ≤ 0,05) en los valores del espesor de las películas a las dos concentraciones de quitosano. Se observó un efecto significativo (p ≤ 0,05) en los valores de humedad a concentraciones de 0, 200 y 400 ppm de aceite esencial. La adición de aceite esencial en películas de quitosano mostró un efecto significativo (p ≤ 0,05) en los valores de permeabilidad al vapor de agua. La concentración de quitosano mostró un efecto significativo (p ≤ 0,05) en transparencia y en los parámetros de color L*, a*, b*. Al variar la concentración de quitosano se observó un incremento significativo (p ≤ 0,05) en los valores de resistencia a la tensión de las películas de quitosano

The effect of the incorporation of lemon grass (Cymbopogon citratus) essential oil at concentrations of 0, 200 and 400 ppm in the physicochemical (thickness, moisture, solubility, water vapor permeability, color, transparency) and mechanical properties (tensile strength and elongation) of chitosan films at concentrations of 1 and 3% was assessed. Results showed a significant effect (p ≤ 0.05) on the thickness values of films at concentrations of 1 and 3% of chitosan. A significant effect (p ≤ 0.05) was observed in the moisture content at concentrations of 0, 200 and 400 ppm of essential oil. The addition of essential oil to chitosan films showed a significant change (p ≤ 0.05) in the water vapor permeability values. The chitosan concentration showed a significant effect (p ≤ 0.05) on transparency and the L*, a*, and b* color parameters. By varying the chitosan concentration, a significant increase (p ≤ 0.05) in the tensile strength values of the chitosan films was observed

**Physicochemical and nutraceutical characterization of sirimbache fruit (Gaultheria glomerata (Cav.) Sleumer)**

The consumption of vegetables with the greatest nutraceutical potential, especially those with high levels of antioxidants such as anthocyanin and phenolic compounds, has become popular among health conscious consumers. The aim of this research was to determine the nutraceutical potential of sirimbache fruits (Gaultheria glomerata (Cav.) Sleumer). Characterization of the berries resulted in the following: 11.4 °Brix, 3.25 pH, 0.35% acidity, 83.74% moisture, 0.16% ash, monomeric anthocyanins (112.88 mg cyanidin 3-glucoside / 100 g of sample), total phenolic compounds (344.37 mg of gallic acid / 100 g of sample) and vitamin C (13.87 mg ascorbic acid/ 100 g of sample). These values indicate that sirimbache is a nutraceutical food of great interest. Therefore, the expansion of sirimbache to health conscious markets may be feasible. Such expansion is of great importance for rural agribusiness, as it could promote the development of new agroindustrial projects in the province of Celendin and other Andean areas of Peru.

Efficiency of three buffers for extracting β-glucosidase enzyme in different soil orders: Evaluating the role of soil organic matter

The objective of this research was to evaluate extraction methods for β-glucosidases comparing three buffer solutions (MUB, acetate, and maleate) at different incubation times (0.5 h to 10 h) and in three different soil orders (Mollisols, Andisols and Ultisols). Seven acidic soils were evaluated, showing differences in pH, OM, and clay contents. To evaluate the effect of OM as enzymes source, one soil of each order was treated to partially remove its OM and then the enzyme assay was performed. When using MUB and maleate buffers the highest (32 and 31 µg-pNP g-soil-1h-1 in average, respectively) were found, and the latter was significantly (p < 0.050) correlated with the soil clay content. The activity obtained with acetate buffer was much lower (38.2 µg-pNP g-soil-1h-1 in average). The use of MUB buffer with 1 h of incubation is suggested as extraction method, showing good reproducibility and allowing to express higher enzyme potential for soil comparisons. For the Andisol and Ultisol, the enzyme activity significantly decreased with the OM removal (%) indicating that OM is the major source of the measured β-glucosidase activity, while a different trend was observed for the Mollisol, in which the mineral fraction (mainly 2:1 type clay) appears to be involved in the increased enzyme activity displayed after the initial OM removal

Energy balance and quality diagnosis of cotton cultivated with native seeds in Lima, Peru

Estudos que apontem o fluxo energético dos agroecossistemas são de grande importância para a produção agrícola mundial, a fim de alcançar uma agricultura mais sustentável. O objetivo deste trabalho foi caracterizar a eficiência energética e realizar o diagnóstico de qualidade em um sistema de cultivo do algodoeiro em Lima, Peru. Foram adotadas metodologias participativas para promover maior interação entre o agricultor e os pesquisadores, a fim de obter o maior número possível de informações a respeito do agroecossistema. O balanço energético foi realizado pela relação entre a produção alcançada (saída) e os gastos energéticos (entrada). Já o diagnóstico de qualidade foi construído através das notas observadas pelo agricultor. Conclui-se que o sistema de cultivo do algodoeiro apresentou balanço energético positivo não satisfatório e baixos indicadores de qualidade para as características aspecto nutricional, competição com plantas espontâneas e arborização.

Studies of energy flow in agroecosystems are very important in agricultural production worldwide, in order to achieve a more sustainable agriculture. The objective of this study was to characterize the energy efficiency and to perform a quality diagnosis of cotton in a cultivation system in Lima, Peru. Participatory methodologies have been adopted to promote greater interaction between farmers and researchers to obtain information about the agroecosystem. The energy balance was achieved by the ratio between achieved production (output) and energy expenditure (input). The quality diagnosis was constructed through the scores observed by the farmer. In conclusion, the cotton cultivation system presented an unsatisfactory positive energy balance and low quality diagnosis related to nutritional factor, weed competition and afforestation.

Aislamiento de péptidos inhibidores de bacterias a partir de bacterias ácido lácticas del tracto digestivo del lechón e identificación mediante prueba proteómica

En la alimentación porcina se usan antibióticos los cuales son un riesgo latente para la salud animal y pública. Los microorganismos son adquiridos del entorno durante las diferentes etapas de su vida, algunas bacterias que colonizan y logran ser parte de la flora natural digestiva ejercen acción antibiótica (sustancias extracelulares llamadas bacteriocinas), las cuales se obtuvieron de sustancias extracelulares de ocho bacterias ácido lácticas (BAL) nativas aisladas de dos lechones (Sus scrofa domesticus); las BAL se identificaron mediante pruebas bioquímicas y pruebas de antagonismo frente a Escherichia fergunsonii y Shigella sannei. La identificación molecular de las bacterias y la sustancia proteica se realizó mediante proteómica, por el método Q proteome™ (método de extracción de la proteína directamente del cultivo de bacterias) donde inicialmente se realizó la digestión bacteriana con el Kit, los productos se sometieron a migraciones, en el gel de policrilamida, seleccionando aquellas de 5 a 2500 KD cortados del gel y una segunda digestión con método convencional con tripsina. Los productos fueron analizados mediante espectrometría de masas en Maldi TOF TOF, obteniendo fragmentos de péptidos que fueron comparados molecularmente a organismo pertenecientes al género Bacillus y luego con Lactobacillus, donde se encontró dos péptidos, llamado ornithine monooxygenase ( Bacillus firmus) y RNase J family beta-CASP ribonuclease (Lactobacillus saerimneri) péptidos que tienen efecto inhibidor de bacterias, antimicrobiano que pueden ser bacteriocinas

In pig feed antibiotics are used which are a latent risk to animal and public health. Microorganisms are acquired from the environment during different stages of life, some bacteria that colonize and become part of the natural digestive flora and exert antibiotic action (extracellular substances called bacteriocins), Extracellular substances of eight lactic acid bacteria native to the digestive tract (Sus scrofa domesticus) were isolated from two post weaned piglets; BALs were identified by biochemical tests and tests of antagonism against Echerichia fergunsonii and Shigella sannei. The molecular identification of the bacteria and the protein substance was performed proteomically mediated by the Q proteome ™ method (method of extraction of the protein directly from the culture of bacteria) where the bacterial digestion was initially performed with the Kit, the products were subjected to Migrations in the polycrylamide gel, selecting those of 5 and 2500 KD cut from the gel and a second digestion with conventional trypsin method. The products were analyzed by mass spectrometry in Maldi TOF TOF, obtaining fragments of peptides that were molecularly compared to organisms belonging to Bacillos and later with genus Lactobacilli, where two peptides named ornithine monooxygenase (Bacillus firmus) and RNase J family Beta-CASP ribonuclease (Lactobacillus saerimneri) peptides that have antimicrobial, inhibitory effect of bacteria that can be bacteriocins