Atividade antioxidante de Piper arboreum, Piper dilatatum e Piper divaricatum / Antioxidant activity of Piper arboreum, Piper dilatatum, and Piper divaricatum

Os óleos essenciais de P. arboreum, P. dilatatum e P. divaricatum foram obtidos por hidrodestilação e analisados por CG-DIC e CG-EM. Extratos etanólicos foram preparados por extração exaustiva. A atividade antioxidante de óleos e extratos foi avaliada por meio do método de sequestro de radicais livres usando 2,2-difenil-1-picril-hidrazila. Os teores de óleos essenciais foram de 0,98%, 1,50% e 0,99% para P. arboreum, P. dilatatum e P. divaricatum, respectivamente. Esses óleos demonstraram riqueza em sesquiterpenos, sendo os principais componentes: biciclogermacreno (28,7%) e ß-copaen-4-α-ol (13,3%) para P. arboreum; germacreno D (16,7%), α-alaskeno (18,9%) e viridiflorol (12,5%) para P. dilatatum; e germacreno D (9,4%), valenceno (11,1%) e γ-cadineno (11,0%) para P. divaricatum. No teste de atividade antioxidante, com base nas percentagens de sequestro de radicais, foram determinados a concentrações efetivas (CE50) e o Índice de Atividade Antioxidante (IAA). Os seguintes valores de CE50 e IAA foram encontrados: ácido ascórbico (usado como referência) 226,84 µg.mL-1 e 5,30; extrato de P. arboreum 239,60 µg.mL-1 e 4,90, e extrato de P. dilatatum 367,70 µg.mL-1 e 3,20, respectivamente. A metodologia utilizada para a atividade antioxidante mostrou-se inadequada para o extrato da P. divaricatum. Os óleos essenciais não apresentaram atividade antioxidante significativa, entretanto, os extratos etanólicos de P. arboreum e de P. dilatatum apresentaram atividade antioxidante expressiva.

were obtained by means of hydrodistillation and analyzed by GC-FID and GC-MS. The ethanolic extracts were prepared by exhaustive extraction. The antioxidant activity of the oils and extracts were evaluated by applying the free radical scavenging method using the 2,2-diphenyl-1-picrylhydrazyl radical. The yields of the essential oils were 0.98%, 1.50% and 0.99% for P. arboreum, P. dilatatum and P. divaricatum, respectively. The oils are rich in sesquiterpenes, and the main components of P. arboreum are the bicyclogermacrene (28.7%) and ß-copaen-4-α-ol (13.3%); of P. dilatatum, the germacrene D (16.7%), α-alaskene (18.9%) and viridiflorol (12.5%); and of P. divaricatum, the germacrene D (9.4%), valencene (11.1%) and γ-cadinene (11.0%). The antioxidant activity test, based on the percentages of radical scavenging, determined the effective concentrations (CE50) and the Antioxidant Activity Index (AAI). The following CE50 and AAI values were found: 226.84 µg.mL-1 and 5.30 for ascorbic acid (used as the reference), 239.60 µg.mL-1 and 4.90 for P. arboreum, and 367.70 µg.mL-1 and 3.20 for P. dilatatum. The antioxidant evaluation using this methodology is not applicable for the P. divaricatum extract. These essential oils did not present a significant antioxidant activity. However, the ethanolic extracts of P. arboreum and P. dilatatum did show a strong antioxidant

Moscas-das-frutas (Diptera: Tephritidae) e seus parasitoides (Hymenoptera: Braconidae) associados às plantas hospedeiras no sul da Bahia / Fruit flies (Diptera: Tephritidae) and their parasitoids (Hymenoptera: Braconidae) associated to host plants in the Southern Region of Bahia State

The association among Anastrepha species, braconid parasitoids and host fruits in southern Bahia is recorded. Doryctobracon areolatus (Szépligeti) was associated with A. serpentina (Wied.) in Pouteria caimito, A. bahiensis Lima in Helicostylis tomentosa, A. sororcula Zucchi in Eugenia uniflora, and A. obliqua (Macquart) in Spondias purpurea. Anatrepha obliqua was unique in fruits of Averrhoa carambola, but associated with D. areolatus, Asobara anastrephae (Muesebeck) and Utetes anastrephae (Viereck). In Achras sapota, A. serpentina was associated with A. anastrephae and D. areolatus, while in Psidium guajava, A. fraterculus (Wied.) and A. sororcula were associated with D. areolatus and U. anastrephae.