Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts / Propriedades bioativas de extratos de folhas e frutos de Persea lingue Ness (Lauraceae)

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.

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.

In vitro inhibitory potential of avocado fruits, Persea americana (Lauraceae) against oxidation, inflammation and key enzymes linked to skin diseases / Inhibidor potencial in vitro de frutos de aguacate, Persea americana (Lauraceae) contra la oxidación, inflamación y enzimas clave vinculadas a enfermedades de la piel

Abstract Introduction: Avocado (Persea americana Mill.) is a member of Lauraceae with one-seeded berry fruit and cultivated in all tropical, subtropical regions in the world and in the Southern coast region of Turkey. Oxidative damage caused by UV can trigger inflammation, resulting in serious inflammatory skin diseases including eczema, seborrheic dermatitis, hyperpigmentation and ageing. Enzyme inhibitors involved in melanogenesis, such as tyrosinase, have been used recently for hyperpigmentation and skin diseases in cosmetic products. Objective: This study aimed to evaluate the antioxidant, anti-inflammatory, anti-tyrosinase activities and total polyphenolic contents of the different parts of P. americana fruit. Methods: The fruit was divided into exocarp, mesocarp, seed, and then methanol and n-hexane extracts were prepared. DPPH and ABTS free radical scavenging capacities and inhibitory potentials on lipid peroxidation were determined to investigate the antioxidant potentials of the extracts. Anti-inflammatory activities of the extracts were evaluated by measuring the stabilization level of the human red blood cell membrane. The tyrosinase inhibitory activities of the samples were determined using mushroom tyrosinase. Results: In general methanol extracts possessed remarkable higher DPPH free radical scavenging activities than n-hexane extracts. The highest activity was determined in methanol extracts of seed (4.17 ± 0.04 mg/mL) followed by exocarp (5.25 ± 0.05 mg/mL). Overall methanol extracts possessed higher ABTS free radical scavenging activities than n-hexane extracts. The greatest ABTS free radical scavenging activity was obtained in methanol extracts of seed (0.03 ± 0.01 mg/mL). In the anti-lipid peroxidation assay, the greatest activity was noticed in methanol extracts of seed (7.71 ± 0.36 µg/mL) followed by exocarp (12.12 ± 0.34 µg/mL), while all n-hexane extracts were inactive. Overall methanol extracts exhibited higher anti-inflammatory and antioxidant properties than n-hexane extracts. However, the maximum anti-tyrosinase activity was determined in n-hexane extracts of exocarp (0.40 ± 0.01 mg/mL) followed by seed (0.46 ± 0.01 mg/mL). Conclusions: These extracts are promising candidates for use as natural products-based antioxidant and anti-inflammatory properties in inflammation-related disease, and also anti-tyrosinase properties in dermatological applications.

Resumen Introducción: El aguacate (Persea americana Mill.) es un miembro de Lauraceae, es una baya de una semilla que se cultiva en todas las regiones tropicales y subtropicales del mundo y la región costera sur de Turquía. El daño oxidativo causado por los rayos ultravioleta puede desencadenar inflamación, lo que posteriormente da como resultado enfermedades inflamatorias graves de la piel como eccema, dermatitis seborreica, hiperpigmentación y envejecimiento. Los inhibidores de enzimas implicados en la melanogénesis, como la tirosinasa, se han utilizado recientemente para la hiperpigmentación y enfermedades de la piel en productos cosméticos. Objetivo: Evaluar las actividades antioxidantes, antiinflamatorias, antitirosinasas y los contenidos polifenólicos totales de las partes del fruto de P. americana. Métodos: El fruto se dividió en tres partes: exocarpio, mesocarpio y semilla, y se prepararon extractos de metanol y n-hexano. Se determinaron las capacidades de eliminación de radicales libres de DPPH y ABTS y los potenciales inhibidores sobre la peroxidación de lípidos para investigar los potenciales antioxidantes de los extractos. Las actividades antiinflamatorias de los extractos se evaluaron midiendo el nivel de estabilización de la membrana de los glóbulos rojos humanos. Las actividades inhibidoras de tirosinasa de las muestras se determinaron utilizando tirosinasa de hongos. Resultados: En general, los extractos de metanol poseían actividades de eliminación de radicales libres de DPPH notablemente más altas que los extractos de n-hexano. La actividad más alta se presentó en extractos metanólicos de semilla (4.17±0.04 mg/mL) seguido del exocarpio (5.25±0.05 mg/mL). En general, los extractos de metanol poseían una mayor actividad de eliminación de radicales libres ABTS que los extractos de n-hexano. La mayor actividad captadora de radicales libres de ABTS se obtuvo en extractos metanólicos de semilla (0.03±0.01 mg/mL). En el ensayo de anti-peroxidación lipídica, la mayor actividad se observó en los extractos metanólicos de semillas (7.71±0.36 µg/mL) seguidos del exocarpio (12.12±0.34 µg/mL), mientras que todos los extractos de n-hexano estaban inactivos. En general, los extractos de metanol exhibieron mayores propiedades anti-inflamatorias y antioxidantes que los extractos de n-hexano. Sin embargo, la actividad anti-tirosinasa máxima se determinó en extractos de exocarpio de n-hexano (0.40±0.01 mg/mL) seguido de semillas (0.46±0.01 mg/mL). Conclusiones: Estos extractos son candidatos prometedores como productos naturales debido a sus propiedades antioxidantes y antiinflamatorias para tratar enfermedades relacionadas con la inflamación, y también propiedades antitirosinasas en aplicaciones dermatológicas.

Efeito da suplementação com óleo de avocado (Persea americana Mill) na temperatura superficial corpórea de equinos antes e após exercício em esteira / [Effect of supplementation with avocado oil (Persea americana Mill) on body surface temperature of horses before and after exercise on treadmill]

Oito equinos foram distribuídos em delineamento randomizado cruzado, sendo um grupo sem suplementação (GC) e outro grupo suplementado com óleo de avocado (GOAv) por um período de sete semanas. Ao fim da sexta semana, os animais foram submetidos a teste padrão de exercício progressivo (TPEP) e, após sete dias, a teste de baixa intensidade e longa duração (BILD). Após o primeiro ciclo, houve período de descanso "washout" de 30 dias para troca de grupos para o segundo ciclo, que seguiu o protocolo do primeiro. A termorregulação foi avaliada com base na temperatura retal e na temperatura superficial corpórea, obtidas por termografia, de 15 regiões de interesse. A temperatura retal e as imagens termográficas foram obtidas antes, um minuto e 15 minutos após o exercício. Não houve diferença entre os grupos GC e GOAv em nenhum momento. Os resultados obtidos neste estudo revelaram que a suplementação de 5% da matéria seca (MS) com óleo de avocado por seis e sete semanas não influenciou na termorregulação com base na temperatura superficial corpórea dos equinos submetidos ao teste padrão de exercício progressivo (TPEP) e ao exercício de baixa intensidade e longa duração (BILD), respectivamente.(AU)

Eight equines were distributed in a randomized crossover design, one control group (CG) without supplementation and another group supplemented (SG) with avocado oil for a period of six weeks. At the end of the sixth week, the animals were submitted to standard exercise test (SET) and after seven days to the low intensity test (LIT). After the first cycle, there was a 30-day washout rest period to exchange groups for the second cycle, which followed the protocol of the first one. Thermoregulation was evaluated based on rectal temperature and body surface temperature of 15 regions of interest obtained by thermography. Rectal temperature and thermographic images were obtained before, one minute and 15 minutes after exercise. There was no difference between the CG and SG at any time. The results obtained in this study revealed that the supplementation of 5% of dry matter with avocado oil for six and seven weeks did not influence the thermoregulation based on the body surface temperature of the horses submitted to SET and LIT, respectively.(AU)

Caracterización de extractos de piel y hojas de Persea americana Mill. y analisis in vitro de sus potenciales propiedades anti-inflamatorias / Characterization of Persea americana Mill. peels and leaves extracts and analysis of its potential in vitro anti-inflammatory properties

Existe una tendencia mundial de incremento en prevalencia de enfermedades no transmisibles, que se caracterizan por un estado pro-inflamatorio crónico. Por lo tanto, es importante estudiar la relación entre alimentos y salud. La palta (Persea americana), sobresale en la industria por su valor nutricional. El procesamiento de la palta genera gran cantidad de subproductos, que contienen bioactivos con propiedades beneficiosas, como polifenoles. El objetivo del presente trabajo fue caracterizar cuatro extractos de palto (acuoso e hidroalcohólico; de hoja y de cáscara) y analizar sus posibles propiedades anti-inflamatorias in vitro. Fueron determinados polifenoles totales (con el método de Folin­Ciocalteau) y capacidad antioxidante (por FRAP y DPPH) de los extractos. Las propiedades anti-inflamatorias de los extractos fueron determinadas por la liberación de NO y de TNF-, y por la expresión génica de TNF-. Los resultados indican que los extractos hidroalcohólicos presentan más polifenoles (p<0,001) y capacidad antioxidante (p<0,001, por FRAP) que los acuosos. Mas aún, observamos que los extractos hidroalcohólicos de hojas presentaron mayores efectos anti-inflamatorios in vitro, especialmente el hidroalcohólico de hoja en liberación de NO (p<0,001, frente a tratamiento con LPS), acuosos e hidroalcohólicos en liberación de TNF- (p<0,05), y solo los hidroalcohólicos en la expresión de TNF- (p<0,01). En conclusión, los extractos hidroalcohólicos de palto, y especialmente el de hoja, presentan propiedades anti-inflamatorias in vitro que pueden ser consideradas para aplicaciones en mejoría de salud humana.

There is a worldwide trend of increasing prevalence of non-communicable diseases characterized by a chronic inflammatory state. Therefore, it is important to study the relationship between food and health. Avocado (Persea americana) stands out in food industry for its nutritional value. Industrials process of avocado generates a large number of by-products, which contain phytochemical compounds with antioxidant properties, such as polyphenols. The objective of the present research was to characterize four aqueous and hydroalcoholic extracts from avocado leaves and peels and analyze it possible anti-inflammatory properties in vitro. Total polyphenol content (with the Folin-Ciocalteau method) and antioxidant capacity (by FRAP and DPPH) were determined. Extracts inflammatory features were measured by NO and TNF- release, and by TNF- gene expression. Our results indicated that hydroalcoholic extracts present higher total polyphenol content (p<0.001) and antioxidant capacity (p<0.001, by FRAP) than the aqueous ones. Furthermore, we report that hydroalcoholic leaves extract presented greater in vitro anti-inflammatory effect, especially the leave hydroalcoholic regarding NO release (p<0.001, against LPS treatment), aqueous and hydroalcoholics regarding TNF- release (p<0.05), and only the hydroalcoholic in the TNF- gene expression (p<0.01). In conclusion, the avocado hydroalcoholic extracts, and especially from leaves, present in vitro anti-inflammatory features that might be considered for human health improvement applications.

Effect of avocado/soybean unsaponifiables on periodontal repair in rats with arthritis and induced periodontitis

Abstract Objective: This study aimed to evaluate the effect of avocado/soybean unsaponifiables (ASU) on periodontal repair in rats with induced periodontitis and arthritis. Methodology: Forty-five rats were submitted to periodontitis induction by insertion of ligatures into the upper second molars, maintained for 15 days. These animals were randomly allocated to 3 groups according to the presence of induced arthritis (ART) and the application of the ASU: Control (CTR) group-healthy animals, where saline solution was administered; ART-animals with induced arthritis, where saline solution was administered; ART/ASU-animals with induced arthritis, where ASU (0.6 mg/ kg) was administered. The drugs were administered daily by gavage and the animals were euthanized after 7, 15 and 30 days of the ligature removal. Bone resorption, inflammatory infiltrate composition and marker proteins expression of the differentiation and formation of osteoclasts (RANKL and TRAP) were assessed. Results: The ART/ASU group presented higher bone volume than the ART group at 7 and 30 days after the ligature removal. Furthermore, the ART group presented higher quantity of inflammatory cells and expression of TRAP and RANKL than the other groups. Conclusion: ASU administration improves the repair of periodontal tissues in an experimental periodontitis model in rats with induced arthritis.

Effects of avocado/soybean unsaponifiables (ASU) on the treatment of ligature-induced periodontitis in rats

Abstract The purpose of this study is to evaluate the effect of the avocado/soybean unsaponifiables (ASU) on the treatment of induced periodontitis in rats. Periodontitis was induced in 84 rats via ligature placement around the second upper molar, which was removed after 7 days, and scaling and root planning (SRP) was performed at this time. Subsequently, the rats were randomly allocated to four groups with 21 animals each: One SRP group in which saline solution was administered (SS), and three groups in which ASU was administered (0.6 g/kg/day), beginning either 7 days before the induction of periodontitis (SRP/ASU-7), on the day of periodontitis induction (SRP/ASU0), or on the day of treatment (SRP/ASU+7). ASU and SS were administered daily by gavage until the sacrifice of the animals (7, 15, and 30 days after SRP). The % bone in the furcation area was evaluated by histomorphometry and micro-CT. The expression of proteins (TRAP, RANKL, and alkaline phosphatase) and mRNA (IL-1β, TNF-α, IL-6, RANKL, and alkaline phosphatase) were evaluated by immunohistochemistry and qPCR. The SRP/ASU+7 group presented a higher percentage of bone fill in the furcation area and higher expression of alkaline phosphatase than in the SRP group (at 7 and 30 days, respectively). The SRP/ASU0 and SRP/ASU+7 groups presented lower expression levels of RANKL mRNA than the SRP and SRP/ASU-7 groups at 15 days. ASU administration on the day of the SRP treatment of the ligature-induced periodontitis promoted subtle beneficial effects on periodontal repair following the treatment of induced periodontitis within the experimental period of 7 days.

Effect of freeze-drying and production process on the chemical composition and fatty acids profile of avocado pulp / Efecto del liofilizado y del proceso de producción en la composición química y el perfil de ácidos grasos de la pulpa de aguacate

Freeze-drying technology is the best dehydration process to preserve shelf-life and allowing avocado to maintain its sensorial and nutritional characteristics. The aim of this work was to determine if the freeze-drying and production condition have an effect on the nutritional quality of the avocado pulp grown in rain-fed and irrigation orchards. Four treatments were applied: non-freeze-dried rain-fed fruits, non-freeze-dried irrigation fruits, freeze-dried rain-fed fruits and freeze-dried irrigation fruits. Results showed that the fruit is made up of 71.4%, 16%, and 12.6% pulp, seed and skin, respectively. The pulp is made up of 71.51%, 19.96%, 2.81%, 0.51% and 1.51% water, lipids, ashes, crude fiber and protein, respectively. Avocado oil is composed by 61%, 18.8%, 11.6% and 7% oleic, palmitic, linoleic, and palmitoleic fatty acids, respectively. The freeze-drying decreased the linoleic acid by 1.43 g/100g. Under rain-fed conditions 4% and 13% less total fat and oleic fatty acid are produced than in irrigation conditions. We conclude that freeze-dried avocado pulp shows slight changes in their nutritional quality.

La tecnología de liofilización es el mejor proceso de deshidratación para mantener mayor vida de anaquel y conservar las propiedades nutricionales y sensoriales de la pulpa del aguacate. El objetivo de este estudio fue determinar si el liofilizado y condición de producción tienen un efecto sobre la calidad nutrimental de la pulpa de aguacate cultivado en huertas de riego y temporal. Se aplicaron 4 tratamientos: frutos de temporal no liofilizado, frutos de riego no liofilizado, frutos liofilizados de temporal y frutos liofilizados de riego. Los resultados muestran que el fruto está compuesto por 71.39, 16 y 12.6% de pulpa, hueso y cascara respectivamente. La pulpa está compuesta por 71.51, 19.96, 2.81, 0.51 y 1.5 % de humedad, lípidos, cenizas, fibra cruda y proteína, respectivamente. El aceite del aguacate está constituido de 61. 18.8, 11.6 y 7% de ácidos grasos oleico, palmítico, linoléico y palmitoleico, respectivamente. El liofilizado disminuyó 1.43 g/100 g de ácido linoléico. Bajo condiciones de temporal se produce 4 y 13% menos grasa total y ácido graso oleico que en condiciones de riego. Se concluye que la pulpa del aguacate liofilizada presenta ligeros cambios en su calidad nutrimental.

Inhibitory effect of Persea americana Mill leaf aqueous extract and itsfractions on PTP1B as therapeutic target for type 2 diabetes / Efecto inhibidor del extracto acuoso de hojas de Persea americana Mill y sus fracciones sobre PTP1Bcomo diana terapéutica para la diabetes tipo 2

Persea Americana Mill (Lauraceae), is a popular plant in Cuba due to its nutritional and medicinal properties. The fruit of the plant is commonly known as avocado. The leaves of Persea americana Mill have been popularly used in the treatment of diabetes incountries in Latin America and Africa. The present study is aimed to explore one of the underlying mechanisms that mediate the antidiabeticefficacy of Persea americana Mill. The aqueous extract from the leaves of the plant and its fractions were evaluated on the inhibitory activity of the protein tyrosine phosphatase 1B (PTP1B) as target of type 2 diabetes. The results revealed that aqueous extract from Pamericana inhibited the enzymatic activity of PTP1B in an extract concentration dependent manner, resulting mainly active the most polarfraction. The present research demonstrated that aqueous extract from P americana and polar fraction (PaF10) have promissory antidiabetic properties mediated by PTP1B, which is a relevant mechanism involved on insulin resistance in type 2 diabetes.

Persea americana Mill. (Lauraceae), es una planta popular en Cuba, debido a sus propiedades nutricionales y medicinales. El fruto de la planta se conoce comúnmente como aguacate. En la etnomedicina las hojas de Persea americana Mill. se han utilizadopopularmente en el tratamiento de la diabetes en varios países en Latinoamérica y África. El presente estudio tuvo el objetivo de explorar laeficacia antidiabética y el mecanismo subyacente, de las hojas de Persea americana. El extracto acuoso de las hojas de la planta y sus fracciones, se evaluaron en un blanco terapéutico de interés en la de diabetes tipo 2: actividad enzimática de la proteína tirosina fosfatasa 1B (PTP1B). Los resultados revelaron que el extracto acuoso de P americana inhibe la actividad enzimática de la enzima PTP1B en una manera dependiente de la concentración, resultando más activa la fracción de mayor polaridad. La presente investigación demostró que elextracto acuoso de P americana y su fracción polar (PaF10), poseen efecto antidiabético promisorio, debido al efecto inhibitorio de PTP1B, mecanismo relevante en la insulino resistencia en la diabetes tipo2.

Histopathologic effect of Persea americana aqueous leaves extract on the liver and kidney of weaner rabbits (California Species) / Efecto histopatológico del extracto acuoso de las hojas de Persea americana sobre el hígado y riñón de conejos destetados (Especie California)

Persea americana (avocado) is widely grown in parts of Southeastern Nigeria and used as a medicinal plant in the treatment of several ailments by alternative medical practitioners but very little research has been carried out on its pharmacotoxicity. This study therefore intends to study the histopathologic effect(s) of Persea americana aqueous leaf extract on the liver and kidneys of rabbits. Fresh leaves of Persea americana were processed using the Soxhlet extraction to obtain the aqueous extract. Three (3) groups of weaner rabbits namely the control, the recommended dose and the high dose groups were given water, 75mg/kg/ and 150mg/kg per day of the extract respectively for 28 days. The animals were sacrificed, the liver and kidney were harvested, fixed in 10 percent buffered formol saline, processed into paraffin wax, sectioned at 5µm and stained by the Haematoxylin and Eosin method and Perl's Prussain Blue method. Slightly better weight gain by the experimental groups suggests that the extract enhances appetite. Histopathology of the liver and kidney of the recommended and high dosage groups were not different from the control group suggesting that the plant extract is beneficial except for the observed loose stool, suggesting increased bowel emptying. This however did not affect weight gain.

La Persea americana (aguacate o palta) crece ampliamente en algunas partes del sudeste de Nigeria y se utiliza como planta medicinal en el tratamiento de varias dolencias por profesionales de la medicina alternativa, pero muy poca investigación se ha llevado a cabo en relación a su toxicidad farmacológica. Este estudio tiene el objetivo de estudiar el efecto histopatológico del extracto acuoso de hojas de Persea americana sobre el hígado y riñones de conejos. Hojas frescas de Persea americana fueron procesadas mediante extracción con Soxhlet para obtener el extracto acuoso. Tres grupos de conejos destetados denominados control, dosis recomendada y dosis alta se les dio agua con 75mg/kg/día y 150mg/kg/día del extracto respectivamente durante 28 días. Los animales fueron sacrificados. Los hígados y riñones fueron recolectados y fijados al 10 por ciento en formol tamponado y luego procesados en parafina. Se tiñeron cortes de 5 um por los métodos de Hematoxilina-Eosina y de Perl (azul de Prusia). Un aumento ligeramente mayor de peso en los grupos experimentales sugiere que el extracto aumenta el apetito de los animales. La histopatología del hígado y riñón en los grupos dosis recomendada y dosis alta no fueron diferentes al grupo control, sugiriendo que el extracto de la planta es beneficioso, excepto por el informe de heces acuosas.

Los polifenoles antioxidantes extraídos del epicarpio de Palta (Persea americana var. Hass) inhiben la ureasa de Helicobacter pylori / Antioxidant polyphenols extracted from Avocado epicarp (Persea americana var. Hass) inhibit Helicobacter pylori urease

Chronic infection by Helicobacter pylori produce chronic gastritis leading to other more severe pathologies as peptic ulcer and gastric adenocarcinoma. New anti-H. pylori agents has been found in natural products, particularly polyphenols. The inhibition of enzymes such us urease appears to be an interesting strategy by which polyphenols could limit the colonization by H. pylori. From the exocarp of Persea americana (avocado fruit), we obtain a procyanidin-rich extract with a 77 percent of gallic acid equivalents (GAE). Such procyanidins derived from epicatechin. with a mean degree of polymerization DPm = 6.10. The antioxidant capacity was assessed by different methods as TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocin. The extract shown inhibitory activity against H. pylori urease with an IC50 = 1.02 ug GAE/mL. In order to obtain clusters of procyanidins with different molecular weights, avocado peel extract was fractioned. A clear relation between the molecular size of procyanidins and their urease inhibitory activity was observed.

La infección crónica por Helicobacter pylori produce gastritis crónica o patologías más severas como la úlcera péptica y adenocarcinoma gástrico. Nuevos agentes anti-H. pylori se han encontrado en los productos naturales, donde destacan los polifenoles. La inhibición de enzimas como la ureasa, resulta ser una estrategia interesante mediante la cual los polifenoles pueden limitar la colonización por H. pylori. A partir del epicarpio del fruto de Persea americana (palto) se obtuvo un extracto polifenólico (77 por ciento de EAG), rico en procianidinas derivadas de epicatequina, con un grado de polimerización DPm = 6.10. La capacidad antioxidante fue evaluada mediante TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocina. El extracto mostró una actividad inhibitoria de la ureasa de H. pylori con un IC50 = 1.02 ug EAG/mL. El fraccionamiento de las procianidinas permitió agruparlas según su peso molecular, observándose una clara relación entre su tamaño y la capacidad de inhibir la ureasa.

Chemical composition, toxicity and larvicidal and antifungal activities of Persea americana (avocado) seed extracts / Composição química, toxicidade, atividade larvicida e antifúngica de extratos de semente de Persea americana (abacate)

The present study had the aim of testing the hexane and methanol extracts of avocado seeds, in order to determine their toxicity towards Artemia salina, evaluate their larvicidal activity towards Aedes aegypti and investigate their in vitro antifungal potential against strains of Candida spp, Cryptococcus neoformans and Malassezia pachydermatis through the microdilution technique. In toxicity tests on Artemia salina, the hexane and methanol extracts from avocado seeds showed LC50 values of 2.37 and 24.13mg mL-1 respectively. Against Aedes aegypti larvae, the LC50 results obtained were 16.7mg mL-1 for hexane extract and 8.87mg mL-1 for methanol extract from avocado seeds. The extracts tested were also active against all the yeast strains tested in vitro, with differing results such that the minimum inhibitory concentration of the hexane extract ranged from 0.625 to 1.25mg L-¹, from 0.312 to 0.625mg mL-1 and from 0.031 to 0.625mg mL-1, for the strains of Candida spp, Cryptococcus neoformans and Malassezia pachydermatis, respectively. The minimal inhibitory concentration for the methanol extract ranged from 0.125 to 0.625mg mL-1, from 0.08 to 0.156mg mL-1 and from 0.312 to 0.625mg mL-1, for the strains of Candida spp., Cryptococcus neoformans and Malassezia pachydermatis, respectively.

O presente estudo teve como objetivo testar os extratos hexânico e metanólico das sementes do abacate, a fim de determinar sua toxicidade em Artemia salina, avaliar a atividade larvicida frente ao Aedes aegypti, bem como verificar o potencial antifúngico in vitro contra cepas de Candida spp, Cryptococcus neoformans e Malassezia pachydermatis, através da técnica de microdiluição. Os extratos hexânico e metanólico das sementes de abacate apresentaram no teste de toxicidade frente à Artemia salina, valores de LC50 2,37 e 24,13mg L-1, respectivamente; contra as larvas do Aedes aegypti os resultados obtidos foram LC50 16,7mg L-1 para o extrato hexânico e 8,87mg L-1 para o extrato metanólico das sementes do abacate. Os extratos testados também foram ativos contra todas as cepas de leveduras, testadas in vitro, apresentando diferentes resultados, onde o MIC do extrato hexânico variou de 0,625 a 1,25mg mL-1, de 0,312 a 0,625mg mL-1 e de 0,031 a 0,625mg mL-1 para as cepas de Candida spp., Cryptococcus neoformans e Malassezia pachydermatis, respectivamente. O intervalo de MIC para o extrato metanólico foi de 0,125 a 0,625mg mL-1, 0,08 a 0,156mg mL-1 e de 0,312 a 0,625mg mL-1, para as exemplares de Candida spp., Cryptococcus neoformans e Malassezia pachydermatis, respectivamente.