Herbivory Damage Increased VOCs in Wild Relatives of Murtilla Plants Compared to Their First Offspring.

Murtilla (Ugni molinae) is a shrub native to Chile that has undergone an incipient domestication process aimed at increasing its productivity. The reduction in intrinsic chemical defenses due to the domestication process has resulted in a decrease in the plant's ability to defend itself against mechanical or insect damage. In response to this damage, plants release volatile organic compounds (VOCs) as a means of defense. To understand how domestication has impacted the production of VOCs in the first offspring of murtilla, we hypothesized that their levels would be reduced due to the induction of mechanical and herbivore damage. To test this hypothesis, we collected VOCs from four offspring ecotypes and three wild relatives of murtilla. We induced mechanical and herbivore damage in the plants and then enclosed them in a glass chamber, where we captured the VOCs. We identified 12 compounds using GC-MS. Our results showed that wild relative ecotypes had a higher VOC release rate of 624.6 µg/cm2/day. Herbivore damage was the treatment that produced the highest release of VOCs, with 439.3 µg/cm2/day in wild relatives. These findings suggest that herbivory triggers defenses through the emission of VOCs, and that domestication has influenced the production of these compounds in murtilla. Overall, this study contributes to bridging the gap in the incipient domestication history of murtilla and highlights the importance of considering the impact of domestication on a plant's chemical defenses.

A phenolic-rich extract from Ugni molinae berries reduces abnormal protein aggregation in a cellular model of Huntington's disease.

Accumulation of misfolded proteins in the brain is a common hallmark of most age-related neurodegenerative diseases. Previous studies from our group identified the presence of anti-inflammatory and antioxidant compounds in leaves derived from the Chilean berry Ugni molinae (murtilla), in addition to show a potent anti-aggregation activity in models of Alzheimer´s disease. However, possible beneficial effects of berry extracts of murtilla was not investigated. Here we evaluated the efficacy of fruit extracts from different genotypes of Chilean-native U. molinae on reducing protein aggregation using cellular models of Huntington´s disease and assess the correlation with their chemical composition. Berry extraction was performed by exhaustive maceration with increasing-polarity solvents. An unbiased automatic microscopy platform was used for cytotoxicity and protein aggregation studies in HEK293 cells using polyglutamine-EGFP fusion proteins, followed by secondary validation using biochemical assays. Phenolic-rich extracts from murtilla berries of the 19-1 genotype (ETE 19-1) significantly reduced polyglutamine peptide aggregation levels, correlating with the modulation in the expression levels of autophagy-related proteins. Using LC-MS and molecular network analysis we correlated the presence of flavonoids, phenolic acids, and ellagitannins with the protective effects of ETE 19-1 effects on protein aggregation. Overall, our results indicate the presence of bioactive components in ethanolic extracts from U. molinae berries that reduce the load of protein aggregates in living cells.

Domestication of Plants of Ugni molinae Turcz (Myrtaceae) Interferes in the Biology of Chilesia rudis (Lepidoptera: Erebidae) Larvae.

In terms of the domestication process in murtilla, studies have found changes in the concentration of phenolic compounds, with reduction of chemical defense of plants, depending on the change in the feeding behavior of insects. Thus, we hypothesized that the domestication of Ugni molinae decreases the content of phenolic compounds and modifies the feeding preference of Chilesia rudis larvae. Leaves of three parental ecotypes and four cultivated ecotypes were used in preference experiments to evaluate the mass gain and leaves consumption of larvae. Phenolic extracts from leaves of U. molinae were analyzed by HPLC. Identified compounds were incorporated in an artificial diet to assess their effect on mass gain, consumption, and survival of the larvae. The presence of phenolic compounds in bodies and feces was also evaluated. In terms of choice assays, larvae preferred parental ecotypes. Regarding compounds, vanillin was the most varied between the ecotypes in leaves. However, plant domestication did not show a reduction in phenolic compound concentration of the ecotypes studied. Furthermore, there was no clear relation between phenolic compounds and the performance of C. rudis larvae. Whether this was because of sequestration of some compounds by larvae is unknown. Finally, results of this study could also suggest that studied phenolic compounds have no role in the C. rudis larvae resistance in this stage of murtilla domestication process.

Volatiles induction in response to mechanical damage is reduced by domestication in murtilla / La inducción de volátiles en respuesta al daño mecánico es reducida por la domesticación en murtilla

Volatiles compounds are involved in defensive induction against insects, playing an important role in insect-plant interaction being induced by response to mechanical damage. However, they could decrease according to the domestication degree in cultivated plants. Currently, it has been established that secondary metabolites are reduced due to the domestication process in murtilla. Hence, the follow question emerges: Are volatile organic compounds induced by mechanical damage reduced in cultivated murtilla plants in relation to wild plants? Two cultivated ecotypes and their respective wild counterparts were sampled. Volatiles compounds were obtained using Porapak-Q columns and analyzed by gas chromatography. Results showed that compounds as 2-hexanone, α-pinene, 2-thujene, 3-thujene and 1,8- cineole were more abundant in wild plants exposed to a mechanical damage than cultivated plants. Hence, these compounds have been associated to induced defense, these results suggest that domestication reduced the induction of defensive volatiles in cultivated murtilla in response to mechanical damage.

Los compuestos volátiles están implicados en la defensa inducida contra insectos, desempeñando un papel importante en esta interacción. Sin embargo, estos compuestos podrían disminuir según el grado de domesticación. Actualmente, se ha reportado que algunos metabolitos secundarios son reducidos en plantas de murtilla domesticadas. Por lo tanto, surge la siguiente pregunta de investigación: ¿Los compuestos orgánicos volátiles inducidos por el daño mecánico son reducidos en plantas cultivadas de murtilla en comparación con plantas silvestres? Para dos ecotipos cultivados y sus respectivas contrapartes silvestres, los compuestos volátiles fueron capturados usando columnas de Porapak-Q y las muestras analizadas por cromatografía gaseosa. Los resultados mostraron que compuestos tales como 2- hexanona, α-pineno, 2-tujeno, 3-tujeno y 1,8-cineol fueron más abundantes en plantas silvestres expuestas a daño mecánico que en cultivadas. Debido a que estos compuestos se han asociado a defensa inducida, estos resultados sugieren que la domesticación reduce la inducción de volátiles en plantas cultivadas sometidas a daño mecánico.

Plant Flavonoid Content Modified by Domestication.

Plant domestication can modify and weaken defensive chemical traits, reducing chemical defenses in plants and consequently their resistance against pests. We characterized and quantified the major defensive flavonols and isoflavonoids present in both wild and cultivated murtilla plants (Ugni molinae Turcz), established in a common garden. We examined their effects on the larvae of Chilesia rudis (Butler) (Lepidoptera: Arctiidae). Insect community and diversity indices were also evaluated. We hypothesized that domestication reduces flavonoid contents and modifies C. rudis preference, the insect community, and diversity. Methanolic extracts were obtained from leaves of U. molinae plants and analyzed by high performance liquid chromatography. Results showed higher insect numbers (86.48%) and damage index (1.72 ± 0.16) in cultivated plants. Four new first records of insects were found associated with U. molinae. Diversity indices, such as Simpson, Shannon, and Margalef, were higher in cultivated plants than in wild plants. Furthermore, eight isoflavonoids were identified in U. molinae leaves for the first time. The five flavonols showed higher concentrations in wild U. molinae leaves (89.8 µg/g) than in cultivated plants (75.2 µg/g); however, no differences were found in isoflavonoids between wild and cultivated plants. The larvae of C. rudis consumed more leaf material of cultivated plants than wild plants in choice (3.8 vs. 0.8 mm2) and no-choice (7.5 vs. 3.0 mm2) assays. Our study demonstrates that domestication in U. molinae reduces the amount of flavonoids in leaves, increasing the preference of C. rudis and the insect community.

Phenolic composition and antioxidant capacity of Ugni molinae Turcz. leaves of different genotypes.

Ugni molinae Turcz. is a native shrub of Chile, known for its edible berries and its leaves, which have been the focus of recent attention, as a good source of phenolic compounds to be used in cosmetics and food products. The aim of this study was to assess the differences in the phenolic composition and antioxidant capacity of the ethanolic extracts from the leaves of 10 genotypes of U. molinae, that were cultivated under the same soil, climate and agronomical management. Antioxidant activity was assessed by complementary methods (ORAC-Fl, FRAP and DPPH assay), phenolic composition of each extract was analyzed by LC-MS. Phenolic and flavonoid total contents were determined by Folin-Ciocalteu and AlCl3 methods. Significative differences were found by these methods, and ellagitannins, gallic acid derivatives and flavonols were identified as responsible for these differences, showing the influence of the genotype on the phenolic composition of U. molinae leaves.

Comparative study of anti-inflammatory activity and qualitative-quantitative composition of triterpenoids from ten genotypes of Ugni molinae / Estudio comparativo de la actividad antiinflamatoria y composición química cualitativa y cuantitativa de triterpenoides de diez genotipos de Ugni molinae

The aim of this study was to assess the differences in qualitative-quantitative composition of triterpenoids and total phenolic contents, together with anti-inflammatory activity of Ugni molinae leaves obtained from ten genotypes. The ethyl acetate (EAE) and ethanol extracts (ETE) were obtained and analyzed. The plant genotypes were grown under same soil and climate conditions and under same agronomic management; the leaves were also harvested under the same conditions. Anti-inflammatory activity was evaluated by mice ear edema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) at a single dose of 200 mg/kg BW of each extract. Composition of triterpenoids and total phenolic contents was determined by HPLC-DAD and Folin-Ciocalteu method, respectively. Ugni molinae leaves of different plant genotypes exhibited significant differences in regard to their anti-inflammatory activity, as well as in qualitative-quantitative composition of triterpenoids and total phenolic content.

El objetivo de este estudio fue establecer las diferencias en la composición cualitativa y cuantitativa de triterpenoides y en los contenidos totales de fenoles, junto con la actividad antiinflamatoria de las hojas de Ugni molinae provenientes de diez genotipos. Los extractos de acetato de etilo (EAE) y etanólicos (ETE) fueron obtenidos y analizados. Los genotipos fueron cultivados bajo las mismas condiciones edafo-climáticas y con el mismo manejo agronómico; las hojas fueron cosechadas bajo las mismas condiciones. La actividad antiinflamatoria fue evaluada en ratones a los que se les indujo un edema en la oreja mediante la aplicación del 12-O-tetradecanoilforbol-13 acetato (TPA) y los extractos fueron evaluados a una dosis única de 200 mg/kg de peso corporal. La composición en triterpenoides y los contenidos de fenoles totales fueron determinados por CLAE-DAD y por el método de Folin-Ciocalteu, respectivamente. Las hojas provenientes de los diferentes genotipos de U. molinae, exhibieron significativas diferencias en sus actividades antiinflamatorias, así como, en el contenido cualitativo y cuantitativo de triterpenoides y en el contenido de fenoles totales.

Domestication in Murtilla (Ugni molinae) Reduced Defensive Flavonol Levels but Increased Resistance Against a Native Herbivorous Insect.

Plant domestication can have negative consequences for defensive traits against herbivores, potentially reducing the levels of chemical defenses in plants and consequently their resistance against herbivores. We characterized and quantified the defensive flavonols from multiple cultivated ecotypes with wild ancestors of murtilla, Ugni molinae Turcz, an endemic plant from Chile, at different times of the year, and examined their effects on a native insect herbivore, Chilesia rudis Butler (Lepidoptera: Arctiidae). We hypothesized that domestication results in a decrease in flavonol levels in U. molinae plants, and that this negatively affected C. rudis performance and preference. Ethanolic extracts were made from leaves, stems, and fruit of murtilla plants for flavonol analysis. Flavonols identified were kaempferol, quercetin, rutin, and quercetin 3-D-ß-glucoside, the last two being the most abundant. More interestingly, we showed differences in flavonol composition between wild and cultivated U. molinae that persisted for most of the year. Relative amounts of all four flavonols were higher in wild U. molinae leaves; however, no differences were found in the stem and fruit between wild and cultivated plants. In choice and no-choice assays, C. rudis larvae gained more mass on, and consumed more leaf material of, wild as compared with cultivated U. molinae plants. Moreover, when applied to leaves, larvae ate more leaf material with increasing concentrations of each flavonol compound. Our study demonstrates that domestication in U. molinae reduced the amount of flavonols in leaves as well as the performance and preference of C. rudis, indicating that these compounds stimulate feeding of C. rudis.