An unexpected guest: a green microalga associated with the arsenic-tolerant shrub Acacia farnesiana.

The best-known plant endophytes include mainly fungi and bacteria, but there are also a few records of microalgae growing endophytically in vascular land plants, some of which belong to the genus Coccomyxa. In this study, we isolated a single-celled photosynthetic microorganism from the arsenic-tolerant shrub Acacia farnesiana, thus we hypothesized that it is an endophytic arsenic-tolerant microalga. The microorganism was identified as belonging to the genus Coccomyxa, and the observation of algal cells within the root tissues strongly suggests its endophytic nature. The alga's tolerance to arsenate (AsV) and its influence on the fitness of A. farnesiana in the presence of AsV were evaluated. Coccomyxa sp. can tolerate up to 2000 µM of AsV for periods shorter than 10 days, however, AsV-tolerance decreased significantly in longer exposure periods. The association with the microalga increased the pigment content in aboveground tissues of A. farnesiana seedlings exposed to AsV for 50 days, without changes in plant growth or arsenic accumulation. This work describes the association, probably endophytic, between an angiosperm and a microalga, confirming the ability of the genus Coccomyxa to form associations with land plants and broadening the known variety of plant endophytes.

Thermal treatment and modified atmosphere packaging delay chilling injury and preserve the quality of cactus stems (Opuntia ficus-indica Mill.) cv Atlixco.

Response surface methodology was applied in order to select the optimal thermal treatment (TT) and modified atmosphere packaging (MAP) needed to preserve minimally processed cactus stems, cv Atlixco. Accordingly, a 42 s/48°C TT together with a 10% CO2 MAP were selected, and their effects evaluated during storage at 4°C. Controls lost more weight (3.8%) than TT (3.3%), MAP (1.4%), and TT-MAP (1.3%) cactus stems. Chilling injury (CI) symptoms decreased and were of a similar magnitude in both MAP and TT-MAP cactus stems, whereas TT-MAP cladodes were better able to preserve their characteristic green color and freshness, even after 28 days. Biochemically, no differences were detected in the electrolyte leakage (EL) of cactus stems, regardless of treatment. However, the high levels of adenosine triphosphate and of the reduced form of ascorbic acid, especially in MAP and TT-MAP cladodes, suggest that an efficient antioxidant system was present in their tissues throughout storage. PRACTICAL APPLICATIONS: In Mexico, cactus stems have been eaten as vegetables since pre-Hispanic times, and their current status as functional foods has helped them spread to various other countries. As cactus stems possess abundant spines, minimal processing is necessary in order to remove them. Stems must also be kept at 4°C so that their quality and general safety as food items are adequately preserved. However, we previously found that this temperature caused significant CI after just 14 days of storage. The present study, therefore, describes the selection of optimal conditions for the application of a TT that, together with a modified atmosphere (MA), induce tolerance to CI and maintain the quality of stems for up to 28 days. As a result, this work provides the necessary postharvest tools to further expand the distribution and sale of minimally processed cactus stems into domestic and international markets.

Antioxidant Capacity In Vitro and In Vivo of Various Ecotypes of Mexican Plum (Spondias purpurea L.).

Spondias purpurea L. is a fruit native to Mexico, however, it is found as far away as Brazil. It possesses a high commercial potential owing to its sensorial and nutritional qualities and its low cost of production. There exists a variety of ecotypes that have not been characterized and their adequate selection process, according to their strongest functional characteristics, will allow the establishment of improvement programs for this genetic resource. The object of this study was the chemical characterization and the determination of the in vitro and in vivo antioxidant capacity of 7 Spondias purpurea L. ecotypes. Differences were observed in the antioxidant capacity and the content of functional compounds among all the ecotypes analyzed. A high total phenolic content and a low flavonoid and carotenoid content were found, both in the epicarp and in the pulp. In each ecotype, the hydrophilic phase presented up to 40 times greater antioxidant capacity compared to the lipophilic phase. The hydrophilic phase of the epicarp of "Costeña Tierra Colorada" had the greatest antioxidant capacity and highest total phenolic content, whereas "Jocote" presented the lowest antioxidant capacity and total phenolic content. A positive correlation was observed between phenol levels and the antioxidant capacity in the epicarp. Regarding antioxidant activity in vivo, it was observed that in all analyzed concentrations of hydrophilic extracts of the epicarp of "Costeña Tierra Colorada" and in the highest "Jocote" concentrations, they provided thermo-protection against heat stress as well as a general well-being to the worm as evidenced by their high mobility.

Achiote (Bixa orellana L.): a natural source of pigment and vitamin E.

Commercialization of agricultural products, including seeds and its derived products, represents an important economic source for developing countries. Natural colorants obtained from the seeds of achiote plant (annatto) have been used since pre-Hispanic times. Also, production of this crop has been important for Mayan cuisine. Annual world production of achiote seeds is approximately 14,500 tons (dry weight). Two thirds of the production is commercialized as dried seeds and the rest as colorant. Latin America produces 60% of the total world production, followed by Africa (27%) and Asia (12%). The main producers in Latin America are Peru, Brazil and Mexico. The purpose of the present paper is to review the most recent literature on Bixa orellana L. focusing on bixin, norbixin, tocotrienols and tocopherols biosynthesis, use and industrial applications of annatto extracts, as well as its nutraceutical potential and its benefits for human health.

Cactus stem (Opuntia ficus-indica Mill): anatomy, physiology and chemical composition with emphasis on its biofunctional properties.

Cactus stem (Opuntia ficus-indica Mill) is native to Mesoamerica and marketed in different forms such as fresh, frozen or pre-cooked. Worldwide, this vegetable is recognized for its pharmaceutical actions, including its antioxidant, diuretic, anticarcinogenic, anti-inflammatory, anti-diabetic, and anti-hypercholesterolemic properties, as well as their antiviral and antispermatogenic effects. However, not all of these properties have been associated with its chemical composition; therefore, this review aims to present and integrate information available on the physiology and anatomy of cactus stem and its chemical composition, focusing on some of the many factors that determine its biofunctionality. © 2017 Society of Chemical Industry.

Studies on phytochemical, antioxidant, anti-inflammatory, hypoglycaemic and antiproliferative activities of Echinacea purpurea and Echinacea angustifolia extracts.

CONTEXT: Echinacea (Asteraceae) is used because of its pharmacological properties. However, there are few studies that integrate phytochemical analyses with pharmacological effects. OBJECTIVE: Evaluate the chemical profile and biological activity of hydroalcoholic Echinacea extracts. MATERIALS AND METHODS: Density, dry matter, phenols (Folin-Ciocalteu method), flavonoids (AlCl3 method), alkylamides (GC-MS analysis), antioxidant capacity (DPPH and ABTS methods), antiproliferative effect (SRB assay), anti-inflammatory effect (paw oedema assay, 11 days/Wistar rats; 0.4 mL/kg) and hypoglycaemic effect (33 days/Wistar rats; 0.4 mL/kg) were determined in three Echinacea extracts which were labelled as A, B and C (A, roots of Echinacea purpurea L. Moench; B, roots, leaves, flowers and seeds of Echinacea purpurea; C, aerial parts and roots of Echinacea purpurea and roots of Echinacea angustifolia DC). RESULTS: Extract C showed higher density (0.97 g/mL), dry matter (0.23 g/mL), phenols (137.5 ± 2.3 mEAG/mL), flavonoids (0.62 ± 0.02 mEQ/mL), and caffeic acid (0.048 mg/L) compared to A and B. A, B presented 11 alkylamides, whereas C presented those 11 and three more. B decreased the oedema (40%) on day 2 similar to indomethacin. A and C showed hypoglycaemic activity similar to glibenclamide. Antiproliferative effect was only detected for C (IC50 270 µg/mL; 8171 µg/mL; 9338 µg/mL in HeLa, MCF-7, HCT-15, respectively). DISCUSSION AND CONCLUSION: The difference in the chemical and pharmacological properties among extracts highlights the need to consider strategies and policies for standardization of commercial herbal extracts in order to guarantee the safety and identity of this type of products.

Liver steatosis and nonalcoholic steatohepatitis: from pathogenesis to therapy. / Hígado graso y esteatohepatitis no alcohólica: patogénesis y tratamiento.

Non-alcoholic fatty liver disease refers to a disease spectrum that ranges from steatosis to non-alcoholic steatohepatitis, which leads to fibrosis, cirrhosis and hepatocellular carcinoma. Given the increasing prevalence of obesity worldwide, the incidence of non-alcoholic fatty liver disease has become a world health problem. Non-alcoholic fatty liver disease is considered to be the hepatic manifestation of metabolic syndrome associated with insulin resistance, central obesity, and type 2 diabetes mellitus. Allegedly, insulin resistance plays a pivotal role in its pathogenesis. Here we highlight non-alcoholic fatty liver disease epidemiology and pathophysiology, its progression towards steatohepatitis with particular emphasis in liver fibrosis and participation of advanced glycation end products. The different treatments reported are described here as well. We conducted a search in PubMed with the terms steatohepatitis, steatosis advanced glycation end products, liver fibrosis and adipocytokines. Articles were selected according to their relevance.

La enfermedad hepática no alcohólica se refiere a un espectro de enfermedades que va desde hígado graso, hasta esteatohepatitis y que puede cursar por fibrosis, cirrosis y hepatocarcinoma. Dado que a nivel mundial se ha incrementado la prevalencia de la obesidad, los cambios en el estilo de vida y la alimentación desbalanceada, la enfermedad hepática no alcohólica se ha convertido en un problema de salud pública. Se le considera como la manifestación hepática del síndrome metabólico, asociada a resistencia a la insulina, obesidad central, diabetes mellitus tipo 2, e hipertrigliceridemia. Se estima que la resistencia a la insulina, juega un papel detonador en la patogénesis de la enfermedad hepática no alcohólica. En este artículo se describen diferentes aspectos de la enfermedad hepática no alcohólica: la epidemiología, la patofisiología, su progresión hacia esteatohepatitis con particular énfasis en la fibrosis hepática, la participación de los productos finales de glicación avanzada, y los diferentes tratamientos reportados. Se realizó una búsqueda de artículos en la base de datos de PubMed con los términos esteatohepatitis, esteatosis, productos finales de glicación avanzada, fibrosis hepática y adipocinas. Los artículos fueron seleccionados por su relevancia en el tema.

Tolerance, arsenic uptake, and oxidative stress in Acacia farnesiana under arsenate-stress.

Acacia farnesiana is a shrub widely distributed in soils heavily polluted with arsenic in Mexico. However, the mechanisms by which this species tolerates the phytotoxic effects of arsenic are unknown. This study aimed to investigate the tolerance and bioaccumulation of As by A. farnesiana seedlings exposed to high doses of arsenate (AsV) and the role of peroxidases (POX) and glutathione S-transferases (GST) in alleviating As-stress. For that, long-period tests were performed in vitro under different AsV treatments. A. farnesiana showed a remarkable tolerance to AsV, achieving a half-inhibitory concentration (IC50) of about 2.8 mM. Bioaccumulation reached about 940 and 4380 mg As·kg(-1) of dry weight in shoots and roots, respectively, exposed for 60 days to 0.58 mM AsV. Seedlings exposed to such conditions registered a growth delay during the first 15 days, when the fastest As uptake rate (117 mg kg(-1) day(-1)) occurred, coinciding with both the highest rate of lipid peroxidation and the strongest up-regulation of enzyme activities. GST activity showed a strong correlation with the As bioaccumulated, suggesting its role in imparting AsV tolerance. This study demonstrated that besides tolerance to AsV, A. farnesiana bioaccumulates considerable amounts of As, suggesting that it may be useful for phytostabilization purposes.

Antioxidant responses of damiana (Turnera diffusa Willd) to exposure to artificial ultraviolet (UV) radiation in an in vitro model; part I; UV-C radiation.

INTRODUCTION: Ultraviolet type C (UV-C) radiation has higher energy than the UV-B radiation and has been less studied because it is completely absorbed by the ozone layer. However, artificial UV-C radiation can generate diverse modifications in the plants. Given that exposure to UV-C for short periods of time increases the antioxidant content, improving the appearance and shelf-life of products, its potential application in postharvest treatments to modify the antioxidant content of medicinal plants, such as damiana (Turnera diffusa), is novel and relevant. OBJECTIVE: To determine the effects of UV-C radiation on enzymatic and non-enzymatic antioxidant defenses, as well as oxidative damage levels, in damiana (Turnera diffusa) plants in vitro. RESULTS: UV-C radiation decreased superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1) activities, the concentration of chlorophylls (a and b), carotenes, vitamin C, and total antioxidant capacity. UV-C radiation increased the phenolic compound levels in damiana. Loss of antioxidant defenses was higher in damiana plants exposed to higher UV-C doses and/or for longer periods. This study suggests that UV-C radiation induces oxidative stress, evidenced as increased protein carbonyls and phenolic compound content, in damiana (T. diffusa). CONCLUSION: Low dose, short exposure to UV-C stimulates phenolic compound content in damiana. Thus, controlled UV-C treatments could be used as postharvest treatment to increase phenolic compound content in damiana plants.

Introducción: La radiación ultravioleta tipo C (UV-C) presenta mayor energía y es menos estudiada que la radiación UV-B, debido a que se considera que es totalmente absorbida por la capa de ozono. Sin embargo, la radiación UV-C artificial es capaz de generar diversas modificaciones en las plantas. Dado que la exposición a UV-C por intervalos de tiempo cortos incrementa la concentración de compuestos antioxidantes, mejorando la apariencia y vida de anaquel de los productos, su potencial aplicación en tratamientos poscosecha para modificar el contenido antioxidante de plantas medicinales, como la damiana (Turnera diffusa), es novedoso y relevante. Objetivo: Determinar el efecto de la radiación UV-C sobre las defensas antioxidantes enzimáticas y no enzimáticas, así como en los niveles de daño oxidativo de damiana (Turnera diffusa) in vitro. Resultados: La radiación UV-C disminuyó la actividad de las enzimas superóxido dismutasa (SOD, EC 1.15.1.1) y peroxidasas totales (POX, CE 1.11.1), la concentración de clorofila (a y b), carotenos, vitamina C y la capacidad antioxidante total, e incrementó el contenido de compuestos fenólicos en damiana. La disminución de las defensas antioxidantes fue mayor en plantas de damiana expuestas a dosis más altas de UV-C o por períodos más largos. Estos resultados sugieren que la radiación UV-C induce estrés oxidativo, evidenciado por el incremento del contenido de carbonilos proteicos y el contenido de compuestos fenólicos en damiana (T. diffusa). Conclusión: Dosis bajas y menor exposición a UV-C estimulan la síntesis de compuestos fenólicos en damiana. Por ello, tratamientos controlados con UV-C podrían emplearse como tratamientos poscosecha para incrementar el contenido de compuestos fenólicos en plantas de damiana.

Antioxidant responses of damiana (Turnera diffusa Willd) to exposure to artificial ultraviolet (UV) radiation in an in vitro model; part ii; UV-B radiation.

INTRODUCTION: Ultraviolet type B (UV-B) radiation effects on medicinal plants have been recently investigated in the context of climate change, but the modifications generated by UV-B radiation might be used to increase the content of antioxidants, including phenolic compounds. OBJECTIVE: To generate information on the effect of exposure to artificial UV-B radiation at different highdoses in the antioxidant content of damiana plants in an in vitro model. METHODS: Damiana plantlets (tissue cultures in Murashige- Skoog medium) were irradiated with artificial UV-B at 3 different doses (1) 0.5 ± 0.1 mW cm-2 (high) for 2 h daily, (2) 1 ± 0,1 mW cm-2 (severe) for 2 h daily, or (3) 1 ± 0.1 mW cm-2 for 4 h daily during 3 weeks. The concentration of photosynthetic pigments (chlorophylls a and b, carotenoids), vitamins (C and E) and total phenolic compounds, the enzymatic activity of superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1), as well as total antioxidant capacity and lipid peroxidation levels were quantified to assess the effect of high artificial UV-B radiation in the antioxidant content of in vitro damiana plants. RESULTS: Severe and high doses of artificial UV-B radiation modified the antioxidant content by increasing the content of vitamin C and decreased the phenolic compound content, as well as modified the oxidative damage of damiana plants in an in vitro model. CONCLUSION: UV-B radiation modified the antioxidant content in damiana plants in an in vitro model, depending on the intensity and duration of the exposure.

Introducción: Los efectos de la radiación ultravioleta tipo B (UV-B) sobre las plantas medicinales se han investigado recientemente en el contexto del cambio climático, pero las modificaciones que genera la radiación UV-B podrían emplearse para modificar el contenido de compuestos antioxidantes, incluyendo los compuestos fenólicos. Objetivo: Generar información sobre el efecto de una alta exposición a UV-B artificial en el contenido antioxidante de damiana (Turnera diffusa, Willd) en un modelo in vitro. Método: Plántulas de damiana en cultivo de tejidos (medio Murashige-Skoog) fueron irradiadas con UV-B artificial en 3 diferentes dosis: (1) 0,5 ± 0,1 mW cm-2 (alto) por 2 h diarias, (2) 1 ± 0,1 mW cm-2 (severa) por 2 h diarias, o (3) 1 ± 0,1 mW cm-2 durante 4 horas diarias por 3 semanas. Se cuantificó la concentración de pigmentos fotosintéticos (clorofilas a y b, carotenoides), vitaminas (C y E) y compuestos fenólicos totales, la actividad enzimática de la superóxido dismutasa (SOD, EC 1.15.1.1) y las peroxidasas totales (POX, EC 1.11.1), así como la capacidad antioxidante total y la peroxidación de lípidos para evaluar el efecto de la alta radiación UV-B artificial en el contenido antioxidante de damiana in vitro. Resultados: Dosis altas y severas de radiación UV-B artificial modificaron el contenido antioxidante incrementando el contenido de vitamina C y disminuyendo el contenido de compuestos fenólicos totales, además de modificar el daño oxidativo de plantas de damiana en un modelo in vitro. Conclusión: La radiación UV-B modifica el contenido antioxidante en damiana en un modelo in vitro, dependiendo de la intensidad y el tiempo de exposición.

Antioxidant responses of damiana (Turnera diffusa Willd) to exposure to artificial ultraviolet (UV) radiation in an in vitro model; part I; UV-C radiation / Respuesta antioxidante en damiana (turnera diffusa willd) expuesta a radiación ultravioleta (UV) artificial en un modelo in vitro; parte I; radiación UV-C

Introduction: Ultraviolet type C (UV-C) radiation has higher energy than the UV-B radiation and has been less studied because it is completely absorbed by the ozone layer. However, artificial UV-C radiation can generate diverse modifications in the plants. Given that exposure to UV-C for short periods of time increases the antioxidant content, improving the appearance and shelf-life of products, its potential application in postharvest treatments to modify the antioxidant content of medicinal plants, such as damiana (Turnera diffusa), is novel and relevant. Objective: To determine the effects of UV-C radiation on enzymatic and non-enzymatic antioxidant defenses, as well as oxidative damage levels, in damiana (Turnera diffusa) plantsin vitro. Results: UV-C radiation decreased superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1) activities, the concentration of chlorophylls (a and b), carotenes, vitamin C, and total antioxidant capacity. UV-C radiation increased the phenolic compound levels in damiana. Loss of antioxidant defenses was higher in damiana plants exposed to higher UV-C doses and/or for longer periods. This study suggests that UV-C radiation induces oxidative stress, evidenced as increased protein carbonyls and phenolic compound content, in damiana (T. diffusa). Conclusion: Low dose, short exposure to UV-C stimulates phenolic compound content in damiana. Thus, controlled UV-C treatments could be used as postharvest treatment to increase phenolic compound content in damiana plants (AU)

Introducción: La radiación ultravioleta tipo C (UV-C) presenta mayor energía y es menos estudiada que la radiación UV-B, debido a que se considera que es totalmente absorbida por la capa de ozono. Sin embargo, la radiación UV-C artificial es capaz de generar diversas modificaciones en las plantas. Dado que la exposición a UV-C por intervalos de tiempo cortos incrementa la concentración de compuestos antioxidantes, mejorando la apariencia y vida de anaquel de los productos, su potencial aplicación en tratamientos poscosecha para modificar el contenido antioxidante de plantas medicinales, como la damiana (Turnera diffusa), es novedoso y relevante. Objetivo: Determinar el efecto de la radiación UV-C sobre las defensas antioxidantes enzimáticas y no enzimá- ticas, así como en los niveles de daño oxidativo de damiana (Turnera diffusa) in vitro. Resultados: La radiación UV-C disminuyó la actividad de las enzimas superóxido dismutasa (SOD, EC 1.15.1.1) y peroxidasas totales (POX, CE 1.11.1), la concentración de clorofila (a y b), carotenos, vitamina C y la capacidad antioxidante total, e incrementó el contenido de compuestos fenólicos en damiana. La disminución de las defensas antioxidantes fue mayor en plantas de damiana expuestas a dosis más altas de UV-C o por períodos más largos. Estos resultados sugieren que la radiación UV-C induce estrés oxidativo, evidenciado por el incremento del contenido de carbonilos proteicos y el contenido de compuestos fenólicos en damiana (T. diffusa). Conclusión: Dosis bajas y menor exposición a UV-C estimulan la síntesis de compuestos fenólicos en damiana. Por ello, tratamientos controlados con UV-C podrían emplearse como tratamientos poscosecha para incrementar el contenido de compuestos fenólicos en plantas de damiana (AU)

Antioxidant responses of damiana (Turnera diffusaWilld) to exposure to artificial ultraviolet (UV) radiation in an in vitro model; part II; UV-B radiation / Respuesta antioxidante en damiana (turnera diffusa willd) expuesta a radiación ultravioleta (UV) artificial en un modelo in vitro; parte II; radiación UV-B

Introduction: Ultraviolet type B (UV-B) radiation effects on medicinal plants have been recently investigated in the context of climate change, but the modifications generated by UV-B radiation might be used to increase the content of antioxidants, including phenolic compounds. Objective: To generate information on the effect of exposure to artificial UV-B radiation at different highdoses in the antioxidant content of damiana plants in an in vitro model. Methods: Damiana plantlets (tissue cultures in Murashige-Skoog medium) were irradiated with artificial UV-B at 3 different doses (1) 0.5 ± 0.1 mW cm-2 (high) for 2 h daily, (2) 1 ± 0,1 mW cm-2 (severe) for 2 h daily, or (3) 1 ± 0.1 mW cm-2 for 4 h daily during 3 weeks. The concentration of photosynthetic pigments (chlorophylls a and b, carotenoids), vitamins (C and E) and total phenolic compounds, the enzymatic activity of superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidases (POX, EC 1.11.1), as well as total antioxidant capacity and lipid peroxidation levels were quantified to assess the effect of high artificial UV-B radiation in the antioxidant content of in vitro damiana plants. Results: Severe and high doses of artificial UV-B radiation modified the antioxidant content by increasing the content of vitamin C and decreased the phenolic compound content, as well as modified the oxidative damage of damiana plants in an in vitro model. Conclusion: UV-B radiation modified the antioxidant content in damiana plants in an in vitro model, depending on the intensity and duration of the exposure (AU)

Introducción: Los efectos de la radiación ultravioleta tipo B (UV-B) sobre las plantas medicinales se han investigado recientemente en el contexto del cambio climático, pero las modificaciones que genera la radiación UV-B podrían emplearse para modificar el contenido de compuestos antioxidantes, incluyendo los compuestos fenólicos. Objetivo: Generar información sobre el efecto de una alta exposición a UV-B artificial en el contenido antioxidante de damiana (Turnera diffusa, Willd) en un modelo in vitro. Método: Plántulas de damiana en cultivo de tejidos (medio Murashige-Skoog) fueron irradiadas con UV-B artificial en 3 diferentes dosis: (1) 0,5 ± 0,1 mW cm-2 (alto) por 2 h diarias, (2) 1 ± 0,1 mW cm-2 (severa) por 2 h diarias, o (3) 1 ± 0,1 mW cm-2 durante 4 horas diarias por 3 semanas. Se cuantificó la concentración de pigmentos fotosintéticos (clorofilas a y b, carotenoides), vitaminas (C y E) y compuestos fenólicos totales, la actividad enzimática de la superóxido dismutasa (SOD, EC 1.15.1.1) y las peroxidasas totales (POX, EC 1.11.1), así como la capacidad antioxidante total y la peroxidación de lípidos para evaluar el efecto de la alta radiación UV-B artificial en el contenido antioxidante de damiana in vitro. Resultados: Dosis altas y severas de radiación UV-B artificial modificaron el contenido antioxidante incrementando el contenido de vitamina C y disminuyendo el contenido de compuestos fenólicos totales, además de modificar el daño oxidativo de plantas de damiana en un modelo in vitro. Conclusión: La radiación UV-B modifica el contenido antioxidante en damiana en un modelo in vitro, dependiendo de la intensidad y el tiempo de exposición (AU)