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The Hass cultivar is one of the most cultivated and distributed avocado varieties throughout the world, having high productivity, nutritional quality, market acceptance and adaptation to different climatic zones (Dreher and Davenport 2013). Anthracnose affects avocado production in tropical and subtropical regions, causing economic losses, especially post-harvest (Fuentes-Aragón et al. 2020). Correct identification of Colletotrichum species causing anthracnose is essential, as different species vary in important phenotypes such as virulence and sensitivity to fungicides (Chen et al. 2016). Twelve samples from batches of avocados with anthracnose were collected in Minas Gerais State, Brazil, in September 2023. The observed symptoms were brown to black depressed circular spots, ranging from a few millimeters to 3 cm in diameter on the epicarp of the fruits, covered in center by mucilaginous layers of pathogen sporulation. Isolation was performed directly from the spore masses and monoconidial isolates were cultured in PDA at 25°C for 7 days for morphological characterization and preserved in sterile water at 4°C. One of the morphotypes commonly recovered from lesions, represented by isolate UCBV 362 (Culture Collection COAD 3843), formed fast-growing colonies having white aerial mycelium and intense salmon-colored sporulation. The cylindrical conidia were 13 to 17.5 µm long and 4.5 to 7 µm wide (average 14.5 x 5.7 µm, N=100), produced on conidiophores dispersed in the aerial mycelium or aggregated on melanized conidiomata formed on the agar. The partial sequence of the second largest subunit of the RNA polymerase II gene (RPB2) from isolate UCBV 362 (GenBank: PQ034617, 1116 nt) showed 99% of coverage and 99.37% of nucleotide identity with the RPB2 sequence of the ex-epitype strain of Colletotrichum nymphaeae ICMP 17918 (=CBS 515.78) (GenBank: JN985506). In a Maximum Likelihood phylogenetic tree composed with RBP2 sequences from reference strains of the Colletotrichum acutatum species complex, the isolate UCBV 362 formed a highly supported clade with the ex-epitype and other reference strains of Colletotrichum nymphaeae, occupying the Clade 2 of the species complex together with C. scovillae and C. simmondsii (Damm et al. 2012). This result shows the reliability of RPB2 for phylogeny and species delimitation within Colletotrichum. To confirm pathogenicity, 10-mm discs from a 7-day-old colony were inoculated at 3 different points on healthy-looking avocado fruits and incubated at 28°C. Uninoculated fruits served as controls. The first symptoms appeared 5 days after inoculation and were similar to those observed in the original samples, while the fruits in the control group remained asymptomatic. The pathogen was reisolated from the lesions and identified morphologically, fulfilling Koch's postulates. Colletotrichum nymphaeae has been associated with avocado anthracnose in Mexico (Fuentes-Aragón et al. 2020). In Brazil, a study based on molecular phylogeny identified Colletotrichum siamense and C. karsti as etiological agents of this disease (Soares et al. 2021). This report expands the range of species that cause avocado anthracnose in Brazil and provides etiological information for the implementation and monitoring of control methods, especially chemical control.
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The utilization of agroindustrial residues, such as avocado peel, as a source of bioactive compounds with antioxidant properties has garnered significant attention. In this study, we investigated the antioxidant potential using the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (oxygen radical absorbance capacity) methods, along with the antimicrobial activity of phenolic compounds extracted from Hass avocado peel. These soluble polyphenols were quantified and identified using high-performance liquid chromatography (HPLC). The research focused on their effects against three fungal pathogens, Verticillium theobromae, Colletotrichum musae, and Aspergillus niger, which significantly impact banana crops, an essential agricultural commodity in Ecuador. The results have revealed that the application of 80% ethanol as an organic solvent led to increased soluble polyphenol content compared to 96% ethanol. Extraction time significantly influenced the phenolic content, with the highest values obtained at 90 min. Interestingly, despite substantial mycelial growth observed across all extract concentrations, the antifungal effect varied among the pathogens. Specifically, V. theobromae exhibited the highest sensitivity, while C. musae and A. niger were less affected. These results underscore the importance of considering both antioxidant and antimicrobial properties when evaluating natural extracts for potential applications in plant disease management.
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Laurel wilt (LW), a lethal vascular disease caused by the ambrosia fungus Harringtonia lauricola, has severely reduced avocado (Persea americana Mill.) production in Florida and decimated populations of native lauraceous trees across twelve U.S. states. All commercial avocado cultivars evaluated to date succumb to the disease, but the speed at which the tree declines varies. Cultivars with West Indian (WI) genetic background develop severe symptoms faster than those with Mexican (M) and Guatemalan (G) pedigree. Genetic resistance to LW is urgently needed, as management relies on costly cultural practices. We screened non-commercial open-pollinated progenies from 19 Mexican and 6 Mexican x Guatemalan accessions, and 2 Guatemalan x West Indian cultivars recognized as tolerant by growers. From the five disease response parameters evaluated, the final disease intensity index and disease severity on the last evaluation day were used to classify genotypes. A wide variability of responses was observed within and among families. Symptomatic plants were present in all families, while some individuals within 15 families remained asymptomatic. 'Colín V-33' (M×G) family was identified as tolerant, and Libres 3 (M), Bladimiro M-06 (M) 'Colinmex' (M×G), 'Collinson' (G×WI), Libres 5 (M) and Rag-13 (M) families were classified as moderately tolerant. This is the first-time tolerance to laurel wilt in avocado is formally reported, though surviving material needs to be propagated for response validation and field testing. Identifying tolerant accessions can help understand the underlying mechanisms and provide breeders with genetic resources for the future incorporation of resistance genes into commercial cultivars.
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During ripening, 'Hass' avocado skin changes from green to purple/black. Low-temperature storage with a controlled atmosphere (CA) is the most widely used method for avocado storage; however, few studies have simulated this technology and considered the days of regular air (RA) storage prior to CA storage. Herein, the effect of delaying the storage of 'Hass' avocado (>30% dry matter) in a CA was examined. Long-term storage conditions (5 °C for 50 days) corresponded to (i) regular air storage (RA), (ii) CA (4 kPa O2 and 6 kPa CO2) and (iii) 10 days in RA + 40 days in a CA and (iv) 20 days in RA + 30 days in a CA. Evaluations were performed during storage and at the ready-to-eat (RTE) stage. Skin color remained unchanged during storage, but at the RTE stage, more color development was observed for fruits stored under CA conditions, as these fruits were purple/black (>50%). At the RTE stage, the anthocyanin content increased, and compared to fruit under RA, fruit under a CA contained a five-fold greater content. A 20-day delay between harvest and CA storage increased the fruit softening rate and skin color development after cold storage, reducing the effectiveness of CA as a postharvest technology for extending storage life.
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OBJECTIVE: Determine the electrophoretic profiles of the extracts of Manihot esculenta, Actinidia Deliciosa and Persea Americana and their possible relationship with Latex-Fruit Syndrome. METHODS: Protein extracts of M. esculenta, P. Americana and A. Deliciosa were prepared through the processes of maceration and solvent extraction from plant samples. In the case of the avocado, a prior extraction by soxhlet was carried out to eliminate the fat. The extracts were vacuum filtered, dialyzed and finally lyophilized. Separation of proteins based on molecular weight was performed by SDS PAGE electrophoresis. The electrophoretic profiles obtained were compared with the allergenic proteins previously identified in the latex extract, in order to determine a possible relationship with Latex-Fruit Syndrome, depending on the molecular weight. RESULTS: The extracts of M. esculenta and P. Americana showed a wide range of protein fractions with molecular weights varying from 10 to 250 KD, finding that the region with the highest concentration of bands was between 20 and 89 KD, (60 and 65%), respectively. A 20-band profile was obtained for the M. esculenta extract (Figure 1), with seven bands sharing similar weights with the latex allergens (Hev b 1, Hev b 2, Hev b3, Hev b 4, Hev b 5, Hev b 6.03, Hev b 8 and Hev b 10) (3-5). For the P. Americana extract, 20 bands were also observed (Figure 2), seven of which presented approximate weights to the Latex allergens (Hev b 1, Hev b 2 Hev b 4 Hev b 6.01 Hev b 6.03 Hev b 8 , Hev b 10 Hev b 11 Hev b 14). The Kiwi extract showed two bands of 19.1 and 22.9 KD, with weights close to latex proteins (figure 3), (Hev b 3 and Hev b 6.01), and allergens (Act d 2 and Act d 6), reported in the literature for this fruit. CONCLUSIONS: When analyzing the relationship between the separated protein fractions and the latex allergens described in the literature, a possible association of 35% was found for the extracts of M. esculenta and P. Americana, and 10% for A. Delicious, with great relevance being the association found with the allergens Hev b 4, Hev b 2, Hev 8 and Hev b 11, which are involved in Latex-Fruit Syndrome. The electrophoretic profiles of the prepared extracts were determined and compared with the Latex allergens. This information generates a contribution for the development of new research and advances in the standardization of these extracts on a large scale and for their future use in diagnostic tests.
OBJETIVO: Determinar los perfiles electroforéticos de los extractos de Manihot esculenta, Actinidia deliciosa y Persea americana y su posible relación con el Síndrome de Látex Fruta. MÉTODOS: Se prepararon extractos proteicos de M. esculenta, P. Americana y A. Deliciosa, a través de los procesos de macerado y extracción con solventes a partir muestras vegetales. En el caso del aguacate, se realizó una extracción previa por soxhlet, para eliminar la grasa. Los extractos se filtraron al vacío, se sometieron a diálisis y por último se liofilizaron. La separación de las proteínas en función del peso molecular se realizó mediante electroforesis SDS PAGE. Se compararon los perfiles electroforéticos obtenidos con las proteínas alergénicas previamente identificadas en el extracto de látex, con el fin de determinar una posible relación con el Síndrome de Látex-Fruta, en función del peso molecular. RESULTADOS: Los extractos de M. esculenta y P. americana mostraron una amplia gama de fracciones proteicas con pesos moleculares que varían desde 10 a 250 KD, encontrando que la región con mayor concentración de bandas se situó entre 20 y 89 KD, (60 y 65 %), respectivamente. Se obtuvo un perfil de 20 bandas para el extracto de M. esculenta (figura 1), con siete bandas que comparten pesos similares con los alérgenos del látex (Hev b 1, Hev b 2, Hev b3, Hev b 4, Hev b 5, Hev b 6.03, Hev b 8 y Hev b 10) (3-5). Para el extracto de P. americana, también se observaron 20 bandas (figura 2), siete de las cuales presentaron pesos aproximados a los alérgenos de Látex (Hev b 1, Hev b 2 Hev b 4 Hev b 6.01 Hev b 6.03 Hev b 8, Hev b 10 Hev b 11 Hev b 14). El extracto de Kiwi mostró dos bandas de 19,1 y 22,9 KD, con pesos cercanos a proteínas de látex (figura 3), (Hev b 3 y Hev b 6.01), y los alérgenos (Act d 2 y Act d 6), reportados en la literatura para esta fruta. CONCLUSIONES: Al analizar la relación existente entre las fracciones proteicas separadas y los alérgenos de los látex descritos en la literatura, se encontró una posible asociación del 35% para los extractos de M. esculenta y P. Americana, y del 10% para A. Deliciosa, siendo de gran relevancia la asociación encontrada con los alérgenos Hev b 4, Hev b 2, Hev 8 y Hev b 11, los cuales se encuentran implicados en el Síndrome de Látex-Fruto. Se lograron determinar los perfiles electroforéticos de los extractos elaborados y se compararon con los alérgenos del Látex. Está información genera un aporte para el desarrollo de nuevas investigaciones y avances en la estandarización de estos extractos a gran escala y para su uso futuro en pruebas diagnósticas.
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Actinidia , Alérgenos , Hipersensibilidade ao Látex , Manihot , Persea , Proteínas de Plantas , Manihot/química , Alérgenos/análise , Actinidia/química , Persea/química , Proteínas de Plantas/análise , Proteínas de Plantas/imunologia , Frutas/química , Látex/química , Extratos Vegetais/química , Eletroforese em Gel de Poliacrilamida , Síndrome , Peso MolecularRESUMO
Grafting, the careful selection of rootstocks and scions, has played a crucial role maintaining Chilean avocado fruit quality standards in a scenario in which climate change and drought-related issues have considerably decreased avocado fruit production in the last fifteen years. The historical use of seedling rootstocks in Chile has experienced a recent shift towards clonal rootstocks, driven by the potential to produce more consistent and predictable crops. This research aims to compare Hass avocado plants grafted on Mexicola seedling and Dusa® clonal rootstocks in a soilless and protected system using (i) a differential expression analysis of root and leaf samples and (ii) a fruit transcriptomic and metabolomic integration analysis to improve our understanding of rootstock-scion interaction and its impact on avocado tree performance and fruit quality. The results demonstrated that no significant transcriptomic and metabolomic differences were identified at fruit level in the ready-to-eat (RTE) stage for Hass avocado fruit from both rootstocks. However, Hass avocados grafted on the clonal rootstock showed greater aerial growth and slightly increased fruit size than the seedling rootstock due to the enrichment of cell wall-remodeling genes as revealed in leaves and fruit at harvest stage.
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The hexane extract of Persea schiedeana Ness (PSN) was analyzed as corrosion inhibitor for the brass surface immersed in 0.5 M HCl. Fourier-transform infrared spectroscopy and a gas chromatographic (GC) and mass spectrometric (MS) were used to identify the PSN extract's functional groups and compound constituents. The functional groups identified were CH 3 and CH 2 functional alkyl groups, C=O stretching vibration of aldehydes, ketones, and carbonyl groups. The GC/MS determined the presence of fatty acids in the PSN extract, where palmitic acid, oleic acid, and ethyl oleate were the major constituents. Electrochemical characterizations were conducted to observe the effect of PSN as corrosion inhibitor on the brass surface. The Rp and Rn calculated from EIS and ENA give the same behavior. Based on the OCP behavior, it was determined that the PSN works as a mix inhibitor, affecting both anodic and cathodic reactions. The corrosion current density (Icorr) suggests that the extract of PSN reduces the corrosion rate of the brass with efficiencies above 90% for all concentrations. The efficiency obtained for each PSN concentration was attributed to forming a corrosion scale of CuO and Cu 2 O , which reacted with the carboxyl group to form copper carboxylates on the metal surface.
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Colorectal cancer is a widespread neoplasia with high ratios of chemoresistance. Phytochemicals in plant-based extracts could be useful to treat colorectal cancer, and/or reduce chemoresistance. Methanolic extract of avocado mesocarp (MEAM) has demonstrated antitumoral properties, depending on the fruit ripening stage (RS). The aim of this study was to analyze the effects of methanolic extracts of "Hass" avocado fruit at different RS on cytotoxicity, antioxidative, anti-inflammatory, anti-invasive, cell cycle, and epithelial-mesenchymal transition inhibition in colorectal adenocarcinoma cell line HT29. The MEAM showed an increasing concentration of total phenolic compounds as the RS progressed, which was correlated with antioxidant capacity measured by the Ferric Reducing Antioxidant Power assay but not with the 2.2-diphenyl-1-picrylhydrazyl assay. The specific phenolic compounds of MEAM were determined by high-performance liquid chromatography, and it was found that concentrations of epicatechin decreased while concentrations of chlorogenic acid increased as the RS progressed. The HT29 cell line was treated with MEAM for 48 h, and all MEAM had a cytotoxic effect, reported by MTT assay, nevertheless, the strongest effect was associated with the presence of chlorogenic acid. MEAM induced apoptosis and cell cycle arrest in phase G0/G1, reported by flow cytometry. Moreover, MEAM inhibited cell migration evidenced by the wound healing assay. On the other hand, MEAM significantly reduced expression of mRNA of tumor necrosis factor-alpha and cyclooxygenase 2. These effects comprise important inhibition of some hallmarks of cancer. This, in turn, may provide interesting guidelines for developing antitumoral intervention agents.
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Antineoplásicos , Neoplasias Colorretais , Persea , Humanos , Frutas/química , Antioxidantes/metabolismo , Persea/química , Metanol , Ácido Clorogênico/análise , Extratos Vegetais/química , Células HT29 , Neoplasias Colorretais/tratamento farmacológicoRESUMO
BACKGROUND: Avocado fruit is rich in xanthophylls, which have been related to positive effects on human health. Xanthophyl acetyltransferases (XATs) are enzymes catalyzing the esterification of carboxylic acids to the hydroxyl group of the xanthophyll molecule. This esterification is thought to increase the lipophilic nature of the xanthophyll and its stability in a lipophilic environment. Studies on XATs in fruits are very scarce, and no studies had been carried out in avocado fruit during postharvest. The objective of this work was to investigate the changes in the expression of genes encoding XAT, during avocado fruit ripening. RESULTS: Avocado fruits were obtained from a local market and stored at 15 °C for 8 days. The fruit respiration rate, ethylene production, and fruit peel's color space parameters (L*, a*, b*) were measured during storage. Fruit mesocarp samples were taken after 1, 3, 5, and 7 days of storage and frozen with liquid nitrogen. Total RNA was extracted from fruit mesocarp, and the quantification of the two genes designated as COGE_ID: 936743791 and COGE_ID: 936800185 encoding XATs was performed with real-time quantitative reverse transcription polymerase chain reaction using actin as a reference gene. The presence of a climacteric peak and large changes in color were recorded during postharvest. The two genes studied showed a large expression after 3 days of fruit storage. CONCLUSIONS: We conclude that during the last stages of ripening in avocado fruit there was an active esterification of xanthophylls with carboxylic acids, which suggests the presence of esterified xanthophylls in the fruit mesocarp. © 2024 Society of Chemical Industry.
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Frutas , Regulação da Expressão Gênica de Plantas , Persea , Proteínas de Plantas , Persea/genética , Persea/crescimento & desenvolvimento , Persea/metabolismo , Persea/química , Persea/enzimologia , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/enzimologia , Frutas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Armazenamento de Alimentos , Xantofilas/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismoRESUMO
Avocado paste (AP) is the main industrial byproduct of its processing, and retains various phenolic compounds (PCs). PCs are known to normalize the plasma lipid profile, but those from avocado byproducts have been minimally studied. We report the normalizing effects of an AP-derived phenolic extract (PE) on the plasma lipid profile of male Wistar rats. A standard (SD) and high-fat diet (HFD) were formulated, and the same diets were supplemented with 1 g/kg of diet of PE (SD + PE and HFD + PE). Rats were fed these diets during an 8-week period. The HFD induced signs of dyslipidemia, but PE treatment countered the decrease in HDL. Relative mRNA expression (real-time PCR) of the hepatic HDL receptor (SCARB1) increased in both groups (SD + PE and HFD + PE), while the LDR receptor (LDLR) increased in SD + PE group. The mRNA expression of apolipoproteins APOA1 and APOB was unaffected. We conclude that PCs from AP can counter a diet-induced decrease in plasma HDL by acting on the mRNA expression of its hepatic receptor.
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Dieta Hiperlipídica , Persea , Ratos , Masculino , Animais , Ratos Wistar , Dieta Hiperlipídica/efeitos adversos , Persea/metabolismo , Fígado/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
The present study evaluated the performance of some enzymatic and non-enzymatic antioxidant systems against oxidative stress for 10 to 30 d of refrigeration (R) and 15 to 50 d in controlled atmosphere (CA) conditions in both exocarp and mesocarp of Hass avocados from early and late harvests and at shelf life (SL) or consumption maturity. The possible relationship of the antioxidant systems with the occurrence of physiological disorders is also evaluated. The results indicate that the enzymatic system-superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), phenylalanine ammonium lyase (PAL) and polyphenoloxidase (PPO)-as well as the non-enzymatic system-such as phenolic compounds (PC)-showed different responses to the stress generated during storage and shelf life. In general, SOD, CAT, PAL and PPO did not significantly vary in storage (R or CA). At consumption maturity, SOD, POD and PAL activities decreased in the mesocarp (RSL and CASL), while CAT increased in the exocarp for CASL15-50d. PC instead decreased in the exocarp as the harvest period progressed while it increased in the mesocarp. Physiological disorders (dark spots) showed only in refrigeration on the exocarp at R30d and in mesocarp at RSL30d coincident with low SOD and low SOD and POD activity values, as well as low PC contents (p-coumaric and its derivatives and caffeic acid derivatives), respectively. The results support the use of CA as a postharvest technology to prevent the development of physiological disorders through the joint action of antioxidative defenses during avocado transport to distant markets until consumption maturity is reached.
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Hass avocado fruit diseases are one of the main marketing constraints in Colombia. To identify and reveal the diversity of fungi associated with diseases in fruits and peduncles, symptomatic samples were collected from 67 farms in the 9 main Hass avocado-producing municipalities of the department of Cauca located in southwestern Colombia. A total of 237 monosporic isolates were obtained that were subjected to DNA extraction, amplification of the ITS region, sequencing and functional diversity analysis based on Hill numbers by municipality and altitude. The results indicated that the genera Pseudocercospora, Diaporthe, Colletotrichum, Neofusiococcum, Lasiodiplodia and Pestatoliopsis were associated with fruit diseases. The genus with the highest number of effective species was Colletotrichum. The ITS region revealed 100% identity of the species Pseudocercospora norchiensis, which was the first report of this pathogen in the crop. There was a greater richness and diversity of associated species in the three municipalities, revealing that the higher the altitude was, the lower the richness and diversity of fungi associated with fruit diseases. These results will provide a better understanding of the identification and diversity of pathogenic microorganisms present in avocado production systems in this region of Colombia.
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Accurate dry matter determination (DM) in Hass avocados is vital for optimal harvesting and ensuring fruit quality. Predictive models based on NIRS need to capture fruit DM gradient. This work aimed to determine the DM content in Hass avocado whole by NIRS scanning different fruit zones. Spectra were recorded for each zone of the fruit: peduncle (P), equator (E), and base (B). The calibration and validation included fruit from different orchards in two harvest cycles. The results show a DM gradient within the fruit: 24.47% (E), 24.68% (B), and 24.79% (P). The DM gradient was observed within the spectra using the RMSi (root mean square) criterion and PCA. The results show that at least one spectrum per fruit zone was needed to represent the variability within the fruit. The performances of the calibration using the whole set of data were R2: 0.74 and standard error of cross-validation (SECV) = 1.18%. In the validation stage using independent validation sets, the models showed similar performance (R2: 0.75, SECV 1.15%) with low values of the standard error of prediction (SEP): 1.62%. These results demonstrate the potential of near-infrared spectroscopy for high-throughput sorting of avocados based on their commercial quality.
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This review provides the first comprehensive appraisal of bioactive compounds and their biological activities in Persea species from 1950 to 2023. Relevant articles from reputable databases, including PubMed, Web of Science, Science Direct and Google Scholar were collected, leading to the isolation of about 141 metabolite compounds, mainly flavonoids, terpenoids, fatty alcohols, lignoids, and γ-lactone derivatives. These compounds exhibit diverse biological activities, including insecticidal, antifeedant, nematicidal, antibacterial, antifungal, antiviral, cytotoxic, anti-inflammatory, and antioxidant properties. The review emphasizes the significant chemical and pharmacological potential of different Persea species, encouraging further research in various fields and medicine. Valuable insights into potential applications of Persea plants are provided.
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Persea , Extratos Vegetais , Etnofarmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Antifúngicos , Compostos Fitoquímicos/química , FitoterapiaRESUMO
Auxins are responsible for a large part of the plant development process. To exert their action, they must move throughout the plant and from cell to cell, which is why plants have developed complex transport systems for indole-3-acetic acid (IAA). These transporters involve proteins that transport IAA into cells, transporters that move IAA to or from different organelles, mainly the endoplasmic reticulum, and transporters that move IAA out of the cell. This research determined that Persea americana has 12 PIN transporters in its genome. The twelve transporters are expressed during different stages of development in P. americana zygotic embryos. Using different bioinformatics tools, we determined the type of transporter of each of the P. americana PIN proteins and their structure and possible location in the cell. We also predict the potential phosphorylation sites for each of the twelve-PIN proteins. The data show the presence of highly conserved sites for phosphorylation and those sites involved in the interaction with the IAA.
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In Peru, almost 50% of the national agricultural products come from the coast, highlighting the production of avocado. Much of this area has saline soils. Beneficial microorganisms can favorably contribute to mitigating the effect of salinity on crops. Two trials were carried out with var. Zutano to evaluate the role of native rhizobacteria and two Glomeromycota fungi, one from a fallow (GFI) and the other from a saline soil (GWI), in mitigating salinity in avocado: (i) the effect of plant growth promoting rhizobacteria, and (ii) the effect of inoculation with mycorrhizal fungi on salt stress tolerance. Rhizobacteria P. plecoglissicida, and B. subtilis contributed to decrease the accumulation of chlorine, potassium and sodium in roots, compared to the uninoculated control, while contributing to the accumulation of potassium in the leaves. Mycorrhizae increased the accumulation of sodium, potassium, and chlorine ions in the leaves at a low saline level. GWI decreased the accumulation of sodium in the leaves compared to the control (1.5 g NaCl without mycorrhizae) and was more efficient than GFI in increasing the accumulation of potassium in leaves and reducing chlorine root accumulation. The beneficial microorganisms tested are promising in the mitigation of salt stress in avocado.
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Anastrepha spp. (Diptera: Tephritidae) infestations cause significant economic losses in commercial fruit production worldwide. However, some plants quickly counteract the insertion of eggs by females by generating neoplasia and hindering eclosion, as is the case for Persea americana Mill., cv. Hass (Hass avocados). We followed a combined transcriptomics/metabolomics approach to identify the molecular mechanisms triggered by Hass avocados to detect and react to the oviposition of the pestiferous Anastrepha ludens (Loew). We evaluated two conditions: fruit damaged using a sterile pin (pin) and fruit oviposited by A. ludens females (ovi). We evaluated both of the conditions in a time course experiment covering five sampling points: without treatment (day 0), 20 min after the treatment (day 1), and days 3, 6, and 9 after the treatment. We identified 288 differentially expressed genes related to the treatments. Oviposition (and possibly bacteria on the eggs' surface) induces a plant hypersensitive response (HR), triggering a chitin receptor, producing an oxidative burst, and synthesizing phytoalexins. We also observed a process of cell wall modification and polyphenols biosynthesis, which could lead to polymerization in the neoplastic tissue surrounding the eggs.
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Magnoliopsida , Persea , Tephritidae , Animais , Feminino , Oviposição , Tephritidae/genética , FrutasRESUMO
Nutritional interventions have been shown to be an interesting approach for the treatment of chronic diseases, including inflammatory bowel disease (IBD). Persea americana Mill. (avocado), is a potential food to be used for the prevention or treatment of intestinal inflammation, due to its nutritional value and pharmacological effects. In this study we evaluated if the dietary intervention with avocado fruit pulp could as an intestinal anti-inflammatory diet using a trinitrobenzenesulfonic acid (TNBS) model of intestinal inflammation in rats. For this purpose, 5, 10 or 20% of avocado fruit pulp was incorporated in the diet of rats, for 21 days before and 7 days after TNBS-induced intestinal inflammation. Dietary intervention with avocado fruit pulp (20%) decreased the extension of colonic lesions (1.38 ± 0.99 vs. 2.67 ± 0.76 cm), weight/length colon ratio (151.03 ± 31.45 vs. 197.39 ± 49.48 cm), inhibited myeloperoxidase activity (891.2 ± 243.2 vs 1603 ± 158.2 U/g), reduced tumor necrosis factor-α (53.94 ± 6.45 vs. 114.9 ± 6.21 pg/mg), interleukin-1ß (583.6 ± 106.2 vs. 1259 ± 81.68 pg/mg) and interferon gamma (27.95 ± 2.97 vs. 47.79 ± 3.51 pg/mg) levels and prevented colonic glutathione depletion (2585 ± 77.2 vs 1778 ± 167.2 nmol/g). The consumption of enriched diet with 20% avocado pulp by 28 days did not promote any alterations in the biochemical or behavioral parameters evaluated. Avocado showed intestinal anti-inflammatory activity, modulating immune response, and acting as antioxidant. The dietary intervention with avocado was safe, suggesting its potential as a complementary treatment in intestinal inflammation.
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Produtos Biológicos , Persea , Ratos , Animais , Ácido Trinitrobenzenossulfônico , Antioxidantes/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológicoRESUMO
Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.(AU)
Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.(AU)
Assuntos
Persea/química , Antibacterianos/análise , Citotoxinas/análise , Antineoplásicos/análiseRESUMO
Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.