The accumulation of chromium in renal tissues promotes the generation of reactive oxygen species (ROS), leading to oxidative stress, genomic and cellular harm, and ultimately necrotic and apoptotic cell death induced by free radicals. Hence, the utilization of antioxidant phytochemicals becomes crucial for cellular defense against oxidative damage. This study endeavors to explore the potential protective effects of an aqueous avocado seed extract (ASE) on rabbit kidneys exposed to chromium-induced damage. Fifteen adult rabbits were distributed into three groups: Group 1 was kept as the control. The second and third groups received a daily dose of K2Cr2O7 (5 mg/kg) intraperitoneally for 2 weeks. While the third group was given an oral dose of ASE (400 mg/kg). In rabbits administered with Cr (VI), kidney homogenates showed a marked increase in Malondialdehyde (MDA) (69.3 ± 4.1 nmol/g) along with a decrease in glutathione (59 ± 5.8 nmol/mg) content and the activity superoxide dismutase (SOD) (0.5 ± 0.05 U/mg protein), glutathione peroxidase (GPx) (16.7 ± 1.1 μmol/mg protein), and catalase (CAT) (73.8 ± 3.9 U/g protein) compared to the levels in control group. Also, the gene expression data for the enzymes SOD, GPx, and CAT dropped dramatically in kidney tissue following Cr (VI) injection. Additionally, Bowman\'s capsule and glomerulus showed degenerative alterations in the kidney\'s histopathology and immunohistochemistry. ASE treatment when administered along with Cr (VI) enhanced the activity and gene expression of antioxidant enzymes and improved histopathological conditions. The findings of this study unequivocally show that avocado seed extract, which is rich in phenolic derivatives, is a potent nephroprotective agent that inhibits nephrotoxicity induced by Cr (VI) in rabbits.

BACKGROUND: Avocado intake improves dietary fat quality, but the subsequent impact on red blood cell (RBC) saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans fatty acid (TFA) composition and association with cardiometabolic health, has not been elucidated.
OBJECTIVE: To compare the effect of consuming one avocado/day relative to habitual diet on RBC-FA profiles, and their association with visceral adiposity and cardiometabolic risk factors (CMRFs) in individuals with abdominal obesity.
METHODS: RBC-FA profiling at baseline, 3- and 6-months was conducted in participants (n=994) from the Habitual Diet and Avocado Trial (HAT). HAT was a multi-site, free-living, parallel-arm intervention study in which participants were randomized to either the Avocado Supplemented group (AVO, usual diet with one avocado/day), or the Habitual Diet group (HAB, usual diet with limited avocado intake) for 6-months. Changes in RBC-FA profiles, a secondary outcome measure, were determined within and between groups using linear regression and mixed effect models, adjusting for age, sex, BMI, clinical site, smoking status and % energy intake from fat at baseline. Association between changes in RBC-FAs with visceral adiposity and CMRFs was assessed after covariate and FDR (<0.05) adjustment.
RESULTS: No major differences in RBC-FA profiles were observed between groups, with the exception of MUFA cis-vaccenic [18:1n-7c], which was significantly higher in AVO (β=0.11 [0.05, 0.17]) compared to the HAB (β=0.03 [-0.03, 0.08]) participants. In the HAB but not AVO group, increases in MUFA cis (18:1n-7c, oleic [18;1n-9c], erucic [22:1n-9c]) and MUFA trans (palmitelaidic [16:1n-7t], vaccenic [18:1n-7t], elaidic [18:1n-9t] and petroselaidic [18;1n-10-12t), as well as PUFA γ-linolenic [18:3n-6], dihomo-γ-linolenic [20:3n-6], arachidonic [20:4n-6] and α-linolenic [18:3n-3] were associated with unfavorable changes in visceral adiposity measures, lipid profiles, glucose, insulin and hsCRP concentrations.
CONCLUSIONS: Daily avocado intake over 6-months modified RBC-MUFA composition, notably 18:1n-7c, and potentially mitigated some of the unfavorable individual RBC FA-CMRF associations observed over time in the HAB group.
BACKGROUND: https://clinicaltrials.gov/study/NCT03528031.

Avocado oil is rich in nutrients beneficial to human health, such as monounsaturated fatty acids, phenolic compounds, tocopherol, and carotenoids, with numerous possibilities for application in industry. This review explores, through a comparative approach, the effectiveness of the supercritical oil extraction process as an alternative to the conventional cold-pressing method, evaluating the differences in the extraction process steps through the effect of temperature and operating pressure on bioactive quality and oil yield. The results reveal that supercritical avocado oil has a yield like that of mechanical cold pressing and superior functional and bioactive quality, especially in relation to α-tocopherol and carotenoids. For better use and efficiency of the supercritical technology, the maturation stage, moisture content, fruit variety, and collection period stand out as essential factors to be observed during pre-treatment, as they directly impact oil yield and nutrient concentration. In addition, the use of supercritical technology enables the full use of the fruit, significantly reducing waste, and adds value to the agro-industrial residues of the process. It produces an edible oil free of impurities, microorganisms, and organic solvents. It is a green, environmentally friendly technology with long-term environmental and economic advantages and an interesting alternative in the avocado market.

In this research, qualitative characteristics were studied under different post-harvest treatments in Hass and Fuerte cultivars of avocado (Persea americana) fruits. The post-harvest treatments performed in fruits of these cultivars comprised Ethrel application and plastic film (membrane) covering. The measurements of qualitative characteristics were related to color; flesh consistency; measurements of titratable acidity, total soluble solids, percentage of total phenolic contents, and ascorbic peroxidase activity; and the real-time (quantitative) polymerase chain reaction (qPCR) of gene expression and enzyme activities of phenylalanine ammonia-lyase (PAL) and beta-galactosidase (β-gal). The experiments found that the application of plastic film has excellent results in retaining qualitative characteristics and enzyme activities via maintaining firmness in higher levels. The plastic film covering appeared to delay ripening without the use of chemicals and, therefore, it has the potential to extend the duration of the post-harvest life of the avocado fruit. Variations between the two cultivars were found in the measurements of total soluble solids (Fuerte cultivar showed an increase of 22%, whereas Hass cultivar showed an increase of 120% in Brix values) and total phenolic contents (Fuerte cultivar showed a decrease of 16% and Hass cultivar showed an increase of 29%). It is worth noting that PAL\'s activity increased significantly (over 44%), as compared to other treatments, and β-galactosidase\'s activity decreased, as compared to other treatments. In conclusion, plastic film covering results in a decrease in the activity of β-galactosidase, as shown by the reaction of hydrolysis (enzyme activity) but also from the expression of the related genes.

The aim of this study was to analyze the content of fatty acids and tocopherols in various components (pulp, seeds, peel) of avocado (Persea americana), which are often neglected as by-products. In addition, the effects of different drying processes on these components were investigated and the health benefits of the main fatty acids contained in avocados were highlighted. The samples were subjected to three drying processes: hot air (HAD), vacuum (VD), and hot-air microwave (HAMD). In all parts of fresh avocado, oleic acid was the most abundant (41.28-57.93%), followed by palmitic acid (19.90-29.45%) and linoleic acid (8.44-14.95%). Drying led to a significant reduction in the oleic acid content, with palmitic acid showing the greatest stability. HAD resulted in higher levels of oleic acid and linoleic acid in dried pulp and peel samples compared with VD and HAMD, while HAMD had the highest content of α-linolenic acid in all parts. In addition, HAMD had the shortest drying time. HAMD duration was 35 min, which was 76.7% shorter than HAD (150 min) and 82.5% shorter than VD (200 min). Considering fatty acid retention and drying efficiency, HAMD appears to have been the most effective method, especially for the avocado peel. Remarkably, the avocado peel consistently contained higher total tocopherol, with δ-tocopherol generally being the most abundant form. The high content of tocopherols, oleic acid, and linoleic acid in the avocado peel suggests promising health benefits.

Avocado lace bug, Pseudocysta perseae (Heidemann) (Hemiptera: Tingidae), is a sap-feeding insect that feeds on the underside of avocado leaves. First observed in 2019, P. perseae has spread throughout the Hawaiian islands, causing premature leaf drop and decrease in avocado yield. Due to Hawai\'i\'s approximately 200 cultivars comprised of all 3 avocado races with extensive racial hybrids, we were able to investigate whether certain cultivars were more prone to experiencing higher P. perseae abundances and infestations compared to others. We conducted longitudinal abundance surveys on Hawai\'i Island across several common avocado varieties monitoring changes in P. perseae abundance. These surveys were supplemented with longitudinal infestation severity surveys across 4 avocado lineages (Mexican, Guatemalan, West Indian, and Guatemalan × West Indian hybrid). Additionally, we collected leaves of \'Sharwil\', \'Hass\', \'Kahalu\'u\', and \'Nishikawa\' cultivars looking at associations between P. perseae abundance and cultivar, herbivory-related biomechanical traits, and soluble sugar content. We found that some cultivars, such as \'Malama\', typically experience lower P. perseae abundances compared to cultivars such as \'Kahalu\'u\', \'Beshore\', and \'Sharwil\'. Guatemalan × West Indian hybrid trees were also shown to have a higher probability of experiencing more severe P. perseae infestations compared to other lineages. Lastly, soluble sugar content, specifically fructose content, had a positive effect on juvenile P. perseae abundance. These findings suggest that cultivar differences in P. perseae infestations may exist, but tree-to-tree leaf compositional differences, such as soluble sugar content, may be a large driver of variation in P. perseae abundance.

Avocado fruit is a rich source of phytonutrients such as vitamins, minerals, carotenoids, carbohydrates, polyphenols and unsaturated fatty acids. However, due to its climacteric nature, fruits are highly susceptible to storage temperature, resulting in poor shelf life and reduced quality. In the present study avocado fruits (Accession CHES-HA-I/I) were stored at different low temperatures (5, 9 and 12 °C with 90-95% relative humidity, RH) to identify optimum low temperature for cold storage. In a further experiment, avocado fruits were treated with 1-methylcyclopropene (1-MCP, 500 ppb) and chitosan (0.5%) to extend the shelf life with better fruit quality. The results showed that storage temperatures had significant effect on physiological, biochemical and antioxidant activities of fruits. Lower physiological loss in weight (PLW), reduced respiration and ethylene production, and higher carbohydrates, protein and fat content were recorded in fruits stored at 9 °C as compared to 12 °C. Similarly, maximum antioxidant properties in terms of free radical scavenging activity (FRSA) and ferric reducing ability of plasma (FRAP) was found in avocado fruits stored at 9 °C. It was also noticed that chilling injury was developed in fruits stored under 5 °C. In addition, exogenous application of 1-MCP significantly reduced respiration and ethylene production rate at 9 °C and extended the shelf life up to 42 days with better fruit quality and more antioxidant activities. However, chitosan treated and control fruits had shelf life up to 28 and 21 days respectively, with minimum nutritional content. From this study it is concluded that a storage temperature of 9 °C and 1-MCP treatment significantly enhanced the shelf life of avocado fruits with better fruit quality as compared to other storage temperatures (5 and 12 °C) and postharvest treatment (chitosan).

Polyphenols from agro-food waste represent a valuable source of bioactive molecules that can be recovered to be used for their functional properties. Another option is to use them as starting material to generate molecules with new and better properties through semi-synthesis. A proanthocyanidin-rich (PACs) extract from avocado peels was used to prepare several semi-synthetic derivatives of epicatechin by acid cleavage in the presence of phenol and thiol nucleophiles. The adducts formed by this reaction were successfully purified using one-step centrifugal partition chromatography (CPC) and identified by chromatographic and spectroscopic methods. The nine derivatives showed a concentration-dependent free radical scavenging activity in the DPPH assay. All compounds were also tested against a panel of pathogenic bacterial strains formed by Listeria monocytogenes (ATCC 7644 and 19115), Staphylococcus aureus (ATCC 9144), Escherichia coli (ATCC 11775 and 25922), and Salmonella enterica (ATCC 13076). In addition, adducts were tested against two no-pathogenic strains, Limosilactobacillus fermentum UCO-979C and Lacticaseibacillus rhamnosus UCO-25A. Overall, thiol-derived adducts displayed antimicrobial properties and, in some specific cases, inhibited biofilm formation, particularly in Listeria monocytogenes (ATCC 7644). Interestingly, phenolic adducts were inactive against all the strains and could not inhibit its biofilm formation. Moreover, depending on the structure, in specific cases, biofilm formation was strongly promoted. These findings contribute to demonstrating that CPC is a powerful tool to isolate new semi-synthetic molecules using avocado peels as starting material for PACc extraction. These compounds represent new lead molecules with antioxidant and antimicrobial activity.

Avocado tree wilt is a disease caused by Phytophthora cinnamomi Rands. Recently, this disease has been associated to Pythium amazonianum, another causal agent. Avocado tree wilt is being currently controlled with synthetic fungicides that kill beneficial microorganisms, polluting the environment and leading to resistance problems in plant pathogens. The current research work aims to provide alternative management using extracts from Proboscidea parviflora W. and Phaseolus lunatus L. to control the development of mycelia in P. amazonianum in vitro. Raw extracts were prepared at UAAAN Toxicology Laboratory, determining the inhibition percentages, inhibition concentrations and inhibition lethal times. Several concentrations of the plant extracts were evaluated using the poisoned medium methodology, showing that both extracts control and inhibit mycelial development, in particular P. lutatus, which inhibits mycelial growth at concentrations lower than 80 mg/L, being lower than P. parviflora extracts. These extracts are promising candidates for excellent control of Pythium amazonianum.

The root microbiota plays a crucial role in plant performance. The use of microbial consortia is considered a very useful tool for studying microbial interactions in the rhizosphere of different agricultural crop plants. Thus, a consortium of 3 compatible beneficial rhizospheric Pseudomonas strains previously isolated from the avocado rhizosphere, was constructed. The consortium is composed of two compatible biocontrol P. chlororaphis strains (PCL1601 and PCL1606), and the biocontrol rhizobacterium Pseudomonas alcaligenes AVO110, which are all efficient root colonizers of avocado and tomato plants. These three strains were compatible with each other and reached stable levels both in liquid media and on plant roots. Bacterial strains were fluorescent tagged, and colonization-related traits were analyzed in vitro, revealing formation of mixed biofilm networks without exclusion of any of the strains. Additionally, bacterial colonization patterns compatible with the different strains were observed, with high survival traits on avocado and tomato roots. The bacteria composing the consortium shared the same root habitat and exhibited biocontrol activity against soil-borne fungal pathogens at similar levels to those displayed by the individual strains. As expected, because these strains were isolated from avocado roots, this Pseudomonas-based consortium had more stable bacterial counts on avocado roots than on tomato roots; however, inoculation of tomato roots with this consortium was shown to protect tomato plants under high-temperature stress. The results revealed that this consortium has side beneficial effect for tomato plants under high-temperature stress, thus improving the potential performance of the individual strains. We concluded that this rhizobacterial consortium do not improve the plant protection against soil-borne phytopathogenic fungi displayed by the single strains; however, its inoculation can show an specific improvement of plant performance on a horticultural non-host plant (such as tomato) when the plant was challenged by high temperature stress, thus extending the beneficial role of this bacterial consortium.