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This research evaluated the physicochemical, nutritional and antioxidant changes of frozen cubes from four mango varieties (Tommy Atkins, Tommy Kent, Keitt, and Kent). The factors were the ripening stage (green-mature or GM and three-quarter or TQ) and freezing with the traditional slow freezing (TSF) or individual quick freezing (IQF). IQF mango cubes kept higher physicochemical, nutritional and antioxidant values (p

Psittacanthus calyculatus es una planta hemiparásita que afecta diversas especies vegetales de gran importancia para el ecosistema. Existen diversos reportes sobre su capacidad antibacteriana debido a que contiene diversos compuestos con actividad antioxidante y antimicrobiana, sin embargo, sobre su actividad antifúngica es prácticamente nula la información disponible. Por lo que el objetivo del presente trabajo fue conocer la actividad antifúngica de extractos de muérdago ante la inhibición de Colletotrichum. gloeosporioides, Fusarium sp. y Curvularia sp. Para ello, se utilizó hoja y flor de muérdago obtenidos de dos hospederos: Prosopis laevigata y Eysenhardtia polystachya. Las muestras se lavaron, deshidrataron y molieron. Posteriormente se realizó una extracción sólido-líquido utilizando el metanol-acetona-agua. Se cuantificó el contenido de fenoles y flavonoides, además el perfil fitoquímico cualitativo. La evaluación de la actividad antifúngica se llevó a cabo con la técnica de dilución en placa con medio PDA. Se determinaron los parámetros de inhibición del crecimiento micelial, esporulación, germinación y se determinó el efecto fungicida o fungistático. Los resultados muestran inhibición mayor al 70% con extractos de hoja y flor, siendo Curvularia sp. el más susceptible con un 98% de inhibición. También hubo reducción de la esporulación y germinación de los fitopatógenos evaluados. Se determinó que la inhibición corresponde a un efecto fungistático. Los resultados revelan alta capacidad de inhibición in vitro de extractos de muérdago contra fitopatógenos de gran importancia para la agricultura.

Biocontrol agents are an environmentally friendly alternative to chemical pesticides against phytopathogens. The effectiveness of metabolites produced by Bacillus atrophaeus B5 for controlling anthracnose produced by Colletotrichum gloeosporioides in harvested fruit and the possible action mechanisms have been studied. Avocado fruit treated with metabolites reduced 54% of anthracnose incidence and nearly 70% of the lesion than untreated fruit. The treatment enhanced the activities of peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase. Additionally, the transcription of PAL and EIN3-like genes related to defense were increased. These results suggest that metabolites produced by B. atrophaeus B5 enhance disease resistance against C. gloeosporioides in avocado fruit. In the fruit, the induced resistance is related to the priming of defense responses. Metabolites in the cell-free supernatant could also be a potential biological preservative for avocado protection.

Fruit losses and wastage are mainly due to postharvest diseases; their control is reduced with pesticides. The excessive use of synthetic fungicides has caused harmful effects on human health and the environment, so it is therefore necessary to reduce their use. The development of new innocuous strategies has led to the use of compounds of natural or biological origin with the capacity to induce the plant defense system, which improves the fruit’s response against future pathogen attacks in addition to reducing the incidence of postharvest diseases. These compounds are known as “elicitors”. Although the use of molecular tools such as RT-qPCR or the measurement of the enzymatic activity of molecular markers makes it possible to determine the activation of the plant defense system in response to the application of an elicitor compound, in recent years, omics technologies such as the transcriptome, proteome, or metabolome have provided new and interesting information that helps to elucidate the molecular aspects involved in the activation of the plant defense system in response to the application of elicitors. This review summarizes recent advances in molecular aspects, highlighting the contribution of omics technologies to a better understanding of fruit defense mechanisms induced by different elicitors.

The quality of tomato (Solanum esculentum L.) fruits is associated with their sensory characteristics and nutrient contents, among which are some secondary metabolites with biological activity. The aim of this study was to assess the effect of ultrasound (US) treatment on the quality and contents of polyphenols, lycopene and rutin in tomatoes after harvest. The application of US under controlled conditions of time and sonication amplitude (SA) induced a significant increase in polyphenol, lycopene and rutin contents in both the pulp and the skin of tomatoes at the beginning and end of the post-harvest evaluation period (0 and 6 days), standing out the 10 min 60% SA and 20 min 20% SA treatments. Additionally, with these treatments, no US effect was observed on the quality parameters (total soluble solids, titratable acidity, pH, firmness, and physiological weight loss). These results reveal that the US application to tomatoes is an attractive technology to increase the content of secondary metabolites in the fruit without affecting its quality.

In this work, the ultrasound-assisted extraction (UAE) (operating conditions of sonication amplitude, pulse-cycle, and extraction time) was investigated to obtain an extract rich in biologically active compounds from Annona muricata leaves. In addition, the content of bioactive compounds from the extract by the optimal UAE conditions (UAE extract) was compared with extracts prepared by decoction and infusion. Moreover, Artemia salina toxicity was evaluated in all extracts. UAE extract (using optimal conditions: 80% amplitude, 0.7 s pulse-cycle, for 4.54 min) contained 178.48 mg/100 mL of soluble phenols, 20.18 mg/100 mL of total flavonoids, 27.81 mg/100 mL of hydrolyzable polyphenols, 167.07 mg/100 mL of condensed tannins, 30.44 mg/100 mL of total alkaloids and 14.62 mg/100 mL of total acetogenins. The UAE extract exhibited a high antioxidant capacity and a higher content of bioactive compounds from ~6 to ~927-fold than decoction or infusion, depending on the type of compound. Twenty-four different phenolic compounds were identified in the samples, and UAE extract produced the highest concentration. All extracts were considered non-toxic using the A. salina test. The UAE extract from A. muricata leaves is a rich source of bioactive compounds and can be utilized to formulate therapeutic drugs or nutraceutical foods.

Los hidrolizados proteínicos son una fuente de péptidos bioactivos (PB) y estos compuestos pueden ejercer un papel importante en la salud humana debido a sus diferentes acividades biológicas. El uso de proteasas de origen vegetal es una alternativa potencial para producir PB. El objetivo de este trabajo fue evaluar la capacidad de inhibición de la hemólisis oxidativa (IHO) y actividad antimicrobiana de hidrolizados y fracciones peptídicas obtenidas de la hidrólisis de proteínas de huevo (ovoalbúmina), leche y soya, con proteasas extraídas de frutos de Bromelia pinguin y Bromelia karatas. En general, todos los hidrolizados y fracciones peptídicas presentaron una alta IHO, siendo la fracción peptídica de ≤1 kDa, obtenida de la hidrólisis de ovoalbúmina con proteasas de B. karatas, la que presentó mayor actividad (98.19%). En contraste, ninguno de los hidrolizados registró actividad antimicrobiana, mientras que las fracciones peptídicas (≤5, ≤10 y ≤30 kDa), obtenidas de la hidrólisis de leche con proteasas de B. pinguin, mostraron la mayor actividad antimicrobina (22.26-23.79% de inhibición), contra Listeria innocua. Los resultados resaltan el potencial de las proteasas de B. pinguin y B. karatas para hidrolizar proteínas de diferentes alimentos y generar hidrolizados y PB con alta actividad antioxidante.

Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), also known as the fall armyworm, is an economically important and widespread polyphagous pest. Microorganisms associated to this insect during life cycle play important ecological roles. We report 3 metagenome-assembled bacterial genomes reconstructed from a metagenome dataset obtained from S. frugiperda larvae F3 3rd-instar reared using artificial diet under laboratory conditions. Genome data for Enterococcus casseliflavus indicated a genome length of 3,659,8333 bp and GC content of 42.54%. Genome data for E. mundtii indicated a genome length of 2,921,701 bp and GC content of 38.37%. Finally, genome data for Lactiplantibacillus plantarum indicated a genome length of 3,298,601 bp, GC content of 44.31%. Genome analysis allowed us to identify genus-specific protein families (PLFams), transporters and antibiotic resistance-related genes among others. DNA sequences were deposited in National Center for Biotechnology Information (https://www.ncbi.nlm.nih.gov/) as Bioproject accession PRJNA899064.