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1.
Artigo em Inglês | MEDLINE | ID: mdl-38661065

RESUMO

OBJECTIVES: The ethanol extract of Persea americana seeds was found to inhibit the development of estrogen-dependent conditions in female Wistar rats, suggesting the ability of its secondary metabolites to interact with estrogen receptors (ERs), either as partial agonists or as antagonists. To test this hypothesis, the abovementioned extract was assessed for its ability to mimic and/or antagonize estradiol effects. METHODS: Two experiments were conducted in ovariectomized (OVX) rats: (1) animals were treated with estradiol valerate (E2V; 1 mg/kg) or P. americana at doses of 25 and 50 mg/kg; (2) animals were treated with E2V alone (0.75 mg/kg) or in combination with P. americana at the abovementioned doses. Treatments were given orally for 3 days and animals were sacrificed for biochemical and histological analyses of the uterus and vagina. RESULTS: When administered alone, P. americana did not change the histomorphology of both organs (uterus and vagina). In combination with E2V, P. americana decreased uterine weight [30 % decrease (p<0.001) at 25 mg/kg and 24 % (p<0.01) at 50 mg/kg] and epithelium height (37 % decrease). This was associated with decreased estradiol levels (at least 86 % decrease, p<0.001) in the uterus. Similarly, vagina epithelium height decreased by at least 34 % (p<0.05) when E2V was co-administered with P. americana. CONCLUSIONS: The seed extract of P. americana contains ER antagonist secondary metabolites accounting for its ability to inhibit the development of estrogen-dependent conditions in female rats.

2.
Plants (Basel) ; 13(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38475450

RESUMO

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.

3.
J Sci Food Agric ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385790

RESUMO

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.

4.
Ann Bot ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38366557

RESUMO

BACKGROUND AND AIMS: Plant water status is important for fruit development, as many fleshy fruits contain large amounts of water. However, there is no information on vascular flows of Persea americana 'Hass' avocado. The aims of this research were to explore the impact of drought stress on the water relations of the 'Hass' avocado plant, and its fruit growth. METHODS: Well-watered and water-stressed 'Hass' avocado plants were compared. Over four weeks, water flows through the shoot and fruit pedicel were monitored using external sap flow gauges. Fruit diameter was monitored using linear transducers (LTs), and stomatal conductance (gs), photosynthesis (A) and leaf and stem water potential (Ñ°leaf and Ñ°stem) were measured to assess the plants' response to water supply. KEY RESULTS: Under well-watered conditions, the average water inflow to the shoot was 72 g d-1. Fruit water inflow was 2.72 g d-1, but there was water loss of 0.37 g d-1 caused by the outflow (loss back into the tree) through the vascular tissues, and 1.06 g d-1 from the fruit skin. Overall, fruit volume increased by 1.4 cm3 d-1. In contrast, water flow into fruit of water-stressed plants decreased to 1.88 g d-1, with the outflow increasing to 0.61 g d-1. As a result, increases in fruit volume were reduced to 0.4 cm3 d-1. Following re-watering, a substantial recovery in growth rate was observed. A, gs, and sap flow to shoots were also reduced during drought conditions. CONCLUSIONS: In summary, a reduction in growth of avocado fruit was observed with induced water deficit, but the isohydric stomatal behaviour of the leaves helped to minimize negative changes in water balance. Also, there was substantial recovery after re-watering, hence the short-term water stress did not decrease avocado fruit size. Negative impacts might appear if the drought treatment were prolonged.

5.
J Med Food ; 27(3): 211-221, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407926

RESUMO

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.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Persea , Humanos , Frutas/química , Antioxidantes/metabolismo , Persea/química , Metanol , Ácido Clorogênico/análise , Extratos Vegetais/química , Células HT29 , Neoplasias Colorretais/tratamento farmacológico
6.
Cell Biochem Biophys ; 82(1): 119-126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37831306

RESUMO

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.


Assuntos
Dieta Hiperlipídica , Persea , Ratos , Masculino , Animais , Ratos Wistar , Dieta Hiperlipídica/efeitos adversos , Persea/metabolismo , Fígado/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
7.
J Trace Elem Med Biol ; 81: 127324, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944220

RESUMO

BACKGROUND: Cadmium is widely reported to interfere with the proper functioning of cells by disrupting cellular redox balance, causing apoptosis, and leading to hepatocellular damage, neurotoxicity, pulmonary edema, cancer, and cardiac and neurodegenerative diseases. Treatment of Cd toxicity with drugs brings undesirable side effects, making it necessary to remove Cd from the body safely without harmful effects. OBJECTIVE: This study aimed to determine how Cd causing malfunctioning of cells could be treated with antioxidant-rich avocado and papaya fruit juices. This work fixated on elucidating and comparing the effects of avocado and papaya fruit juice on Cd-dependent impairment in memory and spatial learning. In addition, various markers of tissue damage, such as the concentration of biomarkers in liver and kidney tissue, the expression of antioxidant enzymes and Cd-induced lipid peroxidation, were analyzed. METHODOLOGY: in silico studies of the phytochemical constituents of avocado and papaya (ligands) were docked against antioxidant enzymes Catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) as macromolecules showed strong hydrogen binding with significant binding capacities. To develop the Cd in vivo model, rats were administered CdCl2 (200 ppm) in drinking water for 7 weeks. After induction of Cd toxicity, rats were post-treated with avocado and papaya (10% w/v each) in a standard diet. After post-treatment, memory and learning were assessed using the Morris water maze behavioural test. Biochemical tests for liver and kidney biomarkers were monitored. To determine the level of ROS, lipid peroxidation was determined by Malondialdehyde (MDA) assay. Gene expression of SOD, CAT and GPx were determined via qRT-PCR. RESULTS: This study demonstrated that Cd accumulation in the liver, kidney and hippocampal tissues was reduced after treatment with avocado and papaya. SOD, CAT and GPX gene expression were upregulated after avocado and papaya juice treatment. Moreover, a comparative analysis between avocado and papaya fruit juices clarified that papaya has more active potential for improving memory and learning, upregulating the expression of antioxidant enzymes, and reducing lipid peroxidation in the liver, kidney, and hippocampus. CONCLUSION: This study suggests that a diet containing papaya and avocado can help treat the lethal effects caused by Cd. Because their active constituents can improve health at the cellular and molecular levels.


Assuntos
Carica , Doença Hepática Induzida por Substâncias e Drogas , Persea , Ratos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Cádmio/análise , Carica/metabolismo , Persea/metabolismo , Frutas/química , Frutas/metabolismo , Superóxido Dismutase/metabolismo , Biomarcadores/metabolismo , Estresse Oxidativo , Peroxidação de Lipídeos
8.
Virus Res ; 339: 199263, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37940077

RESUMO

Avocado sunblotch viroid (ASBVd) is the type species of the family Avsunviroidae and the causal agent of avocado sunblotch disease. The disease is characterised by the presence of chlorotic lesions on avocado fruit, leaves and/or stems. Infected trees may remain without chlorosis for extended periods of time, though distorted growth and reduced yield has been observed in these cases. The molecular effects of ASBVd on avocado, and members of the Avsunviroidae on their respective hosts in general, remain poorly understood. Host global transcriptomic studies within the family Pospiviroidae have identified several host pathways that are affected during these plant-pathogen interactions. In this study, we used RNA sequencing to investigate host gene expression in asymptomatic avocado nursery trees infected with ASBVd. Transcriptome data showed that 631 genes were differentially expressed, 63 % of which were upregulated during infection. Plant defence responses, phytohormone networks, gene expression pathways, secondary metabolism, cellular transport as well as protein modification and degradation were all significantly affected by ASBVd infection. This work represents the first global gene expression study of ASBVd-infected avocado, and the transcriptional reprogramming observed during this asymptomatic infection improves our understanding of the molecular interactions underlying broader avsunviroid-host interactions.


Assuntos
Persea , Viroides , Persea/genética , Árvores , Viroides/genética , Infecções Assintomáticas , RNA Viral/genética , Perfilação da Expressão Gênica , Expressão Gênica , Doenças das Plantas
9.
Plants (Basel) ; 12(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068643

RESUMO

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.

10.
EFSA J ; 21(12): e8493, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38130321

RESUMO

Following an EFSA commodity risk assessment of bonsai plants (Pinus parviflora grafted on Pinus thunbergii) imported from China, the EFSA Plant Health Panel performed a pest categorisation of Pestalotiopsis microspora, a clearly defined plant pathogenic fungus of the family Pestalotiopsidaceae. The pathogen was reported on a wide range of monocotyledonous, dicotyledonous and gymnosperms, either cultivated or wild plant species, causing various symptoms such as leaf spot, leaf blight, scabby canker, fruit spot, pre- and post-harvest fruit rot and root rot. In addition, the fungus was reported as an endophyte on a wide range of asymptomatic plant species. This pest categorisation focuses on the hosts that are relevant for the EU and for which there is robust evidence that the pathogen was formally identified by a combination of morphology, pathogenicity and multilocus sequencing analyses. Pestalotiopsis microspora was reported in Africa, North, Central and South America, Asia and Oceania. In the EU, it was reported in the Netherlands. There is a key uncertainty on the geographical distribution of P. microspora worldwide and in the EU, because of the endophytic nature of the fungus, the lack of surveys, and because in the past, when molecular tools were not fully developed, the pathogen might have been misidentified as other Pestalotiopsis species or other members of the Pestalodiopsidaceae family based on morphology and pathogenicity tests. Pestalotiopsis microspora is not included in Commission Implementing Regulation (EU) 2019/2072. Plants for planting, fresh fruits, bark and wood of host plants as well as soil and other growing media associated with plant debris are the main pathways for the entry of the pathogen into the EU. Host availability and climate suitability in parts of the EU are favourable for the establishment and spread of the pathogen. The introduction and spread of the pathogen into the EU are expected to have an economic and environmental impact where susceptible hosts are grown. Phytosanitary measures are available to prevent the introduction and spread of the pathogen into the EU. Unless the restricted distribution in the EU is disproven, Pestalotiopsis microspora satisfies all the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest.

11.
Pathogens ; 12(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38133301

RESUMO

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.

12.
Inflammopharmacology ; 31(6): 3243-3262, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37936023

RESUMO

Persea americana Mill. (avocado fruit) has many health benefits when added to our diet due to various pharmacological activities, such as preventing bone loss and inflammation, modulating immune response and acting as an antioxidant. In the current study, the total ethanol extract (TEE) of the fruit was investigated for in vitro antioxidant and anti-inflammatory activity via DPPH and cyclooxygenase enzyme inhibition. Biological evaluation of the antiarthritic effect of the fruit extract was further investigated in vivo using Complete Freund's Adjuvant (CFA) arthritis model, where the average percentages of body weight change, inhibition of paw edema, basal paw diameter/weight and spleen index were estimated for all animal groups. Inflammatory mediators such as serum IL-6 and TNF-α were also determined, in addition to histopathological examination of the dissected limbs isolated from all experimental animals. Eighty-one metabolites belonging to different chemical classes were detected in the TEE of P. americana fruit via UPLC/HR-ESI-MS/MS. Two classes of lyso-glycerophospholipids; lyso-glycerophosphoethanolamines and lysoglycerophosphocholines were detected for the first time in avocado fruit in the positive mode. The TEE of fruit exhibited significant antioxidant and anti-inflammatory activity in vitro. In vivo anti-arthritic activity of the fruit TEE improved paw parameters, inflammatory mediators and spleen index. Histopathological findings showed marked improvements in the arthritic condition of the excised limbs. Therefore, avocado fruit could be proposed to be a powerful antioxidant and antiarthritic natural product.


Assuntos
Artrite Experimental , Persea , Animais , Persea/química , Frutas/química , Extratos Vegetais/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Espectrometria de Massas em Tandem , Anti-Inflamatórios , Artrite Experimental/induzido quimicamente , Etanol/química , Compostos Fitoquímicos/uso terapêutico , Mediadores da Inflamação/metabolismo
13.
BMC Plant Biol ; 23(1): 548, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37936068

RESUMO

A plant's defense against pathogens involves an extensive set of phytohormone regulated defense signaling pathways. The salicylic acid (SA)-signaling pathway is one of the most well-studied in plant defense. The bulk of SA-related defense gene expression and the subsequent establishment of systemic acquired resistance (SAR) is dependent on the nonexpressor of pathogenesis-related genes 1 (NPR1). Therefore, understanding the NPR1 pathway and all its associations has the potential to provide valuable insights into defense against pathogens. The causal agent of Phytophthora root rot (PRR), Phytophthora cinnamomi, is of particular importance to the avocado (Persea americana) industry, which encounters considerable economic losses on account of this pathogen each year. Furthermore, P. cinnamomi is a hemibiotrophic pathogen, suggesting that the SA-signaling pathway plays an essential role in the initial defense response. Therefore, the NPR1 pathway which regulates downstream SA-induced gene expression would be instrumental in defense against P. cinnamomi. Thus, we identified 92 NPR1 pathway-associated orthologs from the P. americana West Indian pure accession genome and interrogated their expression following P. cinnamomi inoculation, using RNA-sequencing data. In total, 64 and 51 NPR1 pathway-associated genes were temporally regulated in the partially resistant (Dusa®) and susceptible (R0.12) P. americana rootstocks, respectively. Furthermore, 42 NPR1 pathway-associated genes were differentially regulated when comparing Dusa® to R0.12. Although this study suggests that SAR was established successfully in both rootstocks, the evidence presented indicated that Dusa® suppressed SA-signaling more effectively following the induction of SAR. Additionally, contrary to Dusa®, data from R0.12 suggested a substantial lack of SA- and NPR1-related defense gene expression during some of the earliest time-points following P. cinnamomi inoculation. This study represents the most comprehensive investigation of the SA-induced, NPR1-dependent pathway in P. americana to date. Lastly, this work provides novel insights into the likely mechanisms governing P. cinnamomi resistance in P. americana.


Assuntos
Persea , Phytophthora , Persea/genética , Phytophthora/fisiologia , Ácido Salicílico/metabolismo , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas
14.
Plants (Basel) ; 12(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687381

RESUMO

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.

15.
Plant Dis ; 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552159

RESUMO

In May 2022, rot symptoms were observed 5 days after storage on fresh avocado fruits cv "Lamb Hass" harvested from a 3.4 ha organic orchard in Chania, Crete exhibiting 30% symptom incidence. Brownish-green sunken lesions and soft rot with dark brown lesions covering up to 50% of the mesocarp on fruits and blackish soft lesions on fruit stem ends were observed. To isolate the pathogens, fruits were surface sterilized using 1% NaOCl for 1 min, placed in 70% ethanol for 30 s and washed twice with sterile distilled water. Then, small pieces were excised from the fruit rot margins and transferred on PDA amended with 0.015% streptomycin-sulfate. Single-spore isolates were incubated on PDA for 10 days and subjected to morphological examination. Two distinct pathogenic fungal isolates were obtained, and their symptoms were re-examined on avocado fruits. The first isolate (A1) obtained from the fruit stem end, initially produced hyaline dense aerial mycelia, being gray and black on the upper and lower surface of the Petri dishes, respectively. The second isolate (A2) obtained from the main body of the fruit, formed round, grayish colonies, with orange conidial aggregates. Based on morphological characteristics (Phillips et al.,2013; Weir et al., 2012), isolates were preliminary identified as Neofusicoccum sp. (A1) and Colletotrichum sp. (A2). Isolates were molecularly identified by sequencing of the ITS-5.8S rRNA, translation elongation factor 1-alpha (tef1) and beta-tubulin (tub2) genes. PCRs were conducted using primer pairs ITS4/ITS5, EF1-728F/EF1986R and Bt2a/Bt2b as well as ITS4/ITS5 and 5'-tef1/3'-tef1 and Bt2a/Bt2b for isolates A1 and A2, respectively (Carbone & Kohn, 1999; Glass & Donaldson, 1995; Rojas et al., 2010; Weir et al., 2012; White et al., 1990). The sequences were deposited into GenBank under the accession numbers OQ852465, OQ867962, OQ867965 for N. luteum and, OQ852466, OQ867963 and OQ867964 for C. gloeosporioides. Based on Multilocus sequence analysis (MLSA), a phylogenetic tree was constructed using concatenated sequences, following Kimura's two parameter model (1980), which confirmed their identity as N luteum and C. gloeosporioides strains. Mature avocado fruits (cv. Hass) were surface sterilized and dried. Consequently, incised fruits were inoculated with mycelial agar plugs (5 mm in diameter) cut from the edge of rapidly growing colonies of N. luteum and C. gloeosporioides strains. Fruits incubated in moist chambers and at 25°C for 5 days in the dark. Fruit bodies and stems were inoculated with the respective isolates and sterile agar plugs in the case of the control. Five fruits were used for each pathogenic trial per fungal isolate, which was repeated twice. After symptom occurrence, these pathogenic isolates were re-isolated successfully and molecularly identified, while exhibiting similar to original symptoms confirming Koch's postulates. While other reports exist on the presence of these pathogens in different countries worldwide, this is the first report of C. gloeosporioides and N. luteum as post-harvest pathogens of avocado, which is an economically important crop of Crete, in Greece (Akgül et al., 2016). This study provides the means for the accurate identification of these fungal pathogens causing avocado fruit rots and taking into consideration the available treatment options can contribute to establishing effective management strategies.

16.
Foods ; 12(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37444254

RESUMO

Avocados (Persea americana) are a unique fruit that can provide health benefits when included in a healthy diet. As health care moves towards precision health and targeted therapies or preventative medicine, it is critical to understand foods and their dietary components. The nutritional composition and plant physiology of the Hass avocado is strikingly different from other fruits. This paper reviews the nutrient and bioactive composition of the edible portion of the Hass avocado (pulp) reported in the literature and from commercial lab analyses of the current market supply of fresh Hass avocados. These results provide comprehensive data on what nutrients and bioactives are in avocado and the quantity of these nutrients. We discuss the reasons for nutrient composition variations and review some potential health benefits of bioactive compounds found in Hass avocados.

17.
Heliyon ; 9(7): e18057, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37483832

RESUMO

Pesticides like Mancozeb are being increasingly indispensable in the control of crop pests. Unfortunately, they have been implicated in genotoxicity due to their ubiquity, toxicological properties, persistence and presence in the food chain. This study sought to evaluate the efficacy of powdered avocado seed on reproductive parameters in the management of oxidative stress in female rabbits caused by the herbicide Mancozeb. Twenty-eight female rabbits aged 7-8 months and weighing between 2780.4 g and 3143.7 g were randomly divided into four groups of seven rabbits each. Each group received for 90 consecutive days distilled water or Mancozeb associated or not with avocado seed powder orally as follows: T1: 10 ml distilled water; T2, T3 and T4: 100 mg/kg bw Mancozeb. This was followed by oral administration of 250, 500, and 0 mg/kg of avocado seed powder for T2, T3, and T4, respectively. Water and feed were distributed ad libitum. Collected data concerned growth, carcass and reproductive performances, hematological and biochemistry characteristics. Results demonstrated that pregnant and lactating female rabbits administered Mancozeb exhibited a significant decrease (P < 0.05) in food intake, body weight, and body weight gain. Female rabbits exposed to Mancozeb had a decrease in litter size and weight from birth to weaning, as well as in weaning body weight and weight increase, fertility and prolificacy rate, milk yield, and daily milk efficiency. However, administration of avocado seed powder reversed (P < 0.05) the trends in these parameters in a dose-dependent manner. The increase in relative weight of the kidney and liver, concentrations of urea, creatinine, alanine and aspartate aminotransferases, mean cell volume, white blood cells, and lymphocytes were all associated with increased Mancozeb rates (P < 0.05). On the contrary, administration of the Mancozeb caused decrease in hemoglobin (Hb), Red blood Cell (RBC) and protein content. Administration of avocado seed powder significantly (P < 0.05) ameliorated the Mancozeb effects on these parameters. Applying 500 mg/kg b.w Avocado seed powder may be suggested as an alternative therapy for reproductive defects induced by Mancozeb in female rabbits.

18.
Plants (Basel) ; 12(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37375905

RESUMO

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.

19.
Med Glas (Zenica) ; 20(2)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37300472

RESUMO

Aim To determine the effectiveness of avocado peel extract (Persea americana Mill) as an antifungal against T. rubrum, which causes dermatophytosis. Methods In vitro laboratory experimental study using a post-testonly control group design analysed active compounds of avocado peel and continued with the antifungal activity test. In each group divided according to the concentration of 0% (negative control), 12.5%, 25%, 37.5%, 50%, 62.5%, 75%, and positive control (2% ketoconazole) antifungal activity test was carried out using the fungus T. rubrum ATCC 28188 for five repetitions. Results The avocado peel extract contained phenolic compounds, flavonoids, tannins, saponins, alkaloids, terpenoids, and glycosides. Antifungal activity test showed a significant difference with the highest mean inhibition zone diameter of T. rubrum, which was demonstrated at a concentration of 75%. Conclusion Avocado peel extract is useful to inhibit growth of Trichophyton rubrum in dose dependent.

20.
Plant Dis ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157101

RESUMO

Adenium (Adenium obesum) and avocado (Persea americana) are commonly grown as exotic houseplants in city apartments of Kazakhstan. In April-May 2020, the wilting symptom was observed on the young stems of five 2-year-old A. obesum plants in a city apartment in Saryarqa District, Astana, Kazakhstan (71°25'E, 51°11'N). Leaves turned yellow and then dried up. Plants were completely wilted within 10 days (Fig. 1A). Similar symptoms were observed in newly grown A. obesum plants in November, 2021. At the same time, lesions were found on the leaves of three 3-month-old P. americana plants. Infected leaves displayed dry, dark-brown lesions and fell off easily (Fig. 2A). Both plants were cultivated side by side. The incidence of affected A. obesum was 80% out of 5 plants and P. americana was 100% out of 3 plants. To isolate the causal agent, the infected tissues from different leaves and stems of A. obesum and P. americana plants were cut into small pieces (5 × 5 mm), washed in 70% ethanol for 5 min, and then rinsed three times with sterile distilled water. Cut pieces were placed on potato dextrose agar (PDA) (Laboratorios Conda S.A., Spain) and incubated at 28°C for 7 days. Ten isolates were obtained from leaves and stems of the A. obesum and P. americana symptomatic samples. All fungal colonies were white initially, turned black gradually, reverse side light yellow (Fig. 1B and Fig. 2B), conidiophores biseriate with globose vesicles, conidia were spherical vesicles, light tan to black color, smooth-walled to roughened, and sizes ranged from 3.0 to 3.5 µm (n = 15) (Fig. 1C and Fig. 2C). These observations indicated that all the isolates resembled Aspergillus spp. (Bryan and Fennell 1965). DNA was extracted using the liquid nitrogen and phenol-chloroform extraction method (Butler 2012). A 526 bp product of the ITS region on rDNA and 568 bp product of the calmodulin protein-coding gene was amplified using following primer pairs ITS4/ITS5 (Abliz et al. 2003) and cmd5/cmd6, respectively (Hong et al. 2005). The PCR reaction was done under the following conditions: initial denaturation at 94°C for 5 min, 35 cycles at 95°C for 30 s to denature, 52°C for 40 s for annealing, and 72°C for 50 s for extension. A final extension step at 72°C for 7 min was also included. The sequencing was done using BigDye® Terminator v3.1 Cycle Sequencing Kit (Applied Biosystems) and the sequence was deposited in GenBank with accession nos. ON519078 (A. obesum ITS), ON519079 (P. americana ITS), OQ358173 (A. obesum calmodulin) and OQ358174 (P. americana calmodulin). These sequences were compared with other sequences of A. niger in GenBank using BLAST analysis (MG569619.1, MT588793.1, MH478660.1, MZ787576.1 and MW086485.1). The results showed that the sequences of ten isolates were identical and had 98-100% identity with those of Aspergillus niger (Fig. 3). The phylogenetic analysis was carried out with MEGA 11 (Tamura et al. 2021). To confirm the pathogenicity, three asymptomatic plants of each were inoculated with a suspension of conidia via pin-prick inoculation (1.0×106 conidia/ml; obtained from 2-week-old cultures). Control plants were inoculated with sterile distilled water. The inoculated plants were placed in climate chamber (BINDER, Germany) and incubated for 10 days at 28°C. Symptoms were developed in leaves of inoculated plants after 2 days in P. americana and after 5 days in A. obesum. Affected leaves turned yellow and their stems started drying. Symptoms of leaves were similar to those observed on naturally infected plants, while control plants remained asymptomatic. Re-isolation of the pathogen confirmed the presence of the A. niger pathogen. To our knowledge, this is the first report of A. niger causing stem rot of A. obesum and leaf spot of P. americana in Kazakhstan. Since different ornamentals are often planted together in gardens and nurseries, growers should be aware of potential transmission of A. niger among them. This finding provides a foundation to further investigate the biology and epidemiology of this disease so the developmentf diagnostic tools and management measures against it.

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