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1.
CienciaUAT ; 18(2): 91-106, ene.-jun. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1569023

RESUMO

Resumen: Los métodos de extracción de fitoquímicos convencionales presentan bajos rendimientos o largos tiempos de proceso. El ultrasonido ofrece alternativas para incrementar el rendimiento en extractos vegetales. El objetivo de este trabajo fue evaluar el efecto de tres métodos de extracción en rendimiento, composición de compuestos fenólicos, actividad antioxidante y estabilidad de extractos de hojas de Plectranthus amboinicus (oreganón). Los métodos de extracción usados fueron: convencional con agitación (EC), asistida con baño de ultrasonidos (EABU) y asistida con sonda de ultrasonido (EASU). Se usó una proporción 1:10 (p/v) orégano:etanol a 35 ± 2 °C. Los rendimientos se calcularon como materia seca del extracto (% ms). Se usó un modelo de pseudo-segundo orden para ajustar las curvas de extracción experimentales de los tres métodos y obtener los parámetros cinéticos. Se determinaron compuestos fenólicos totales (CFT) y actividad antioxidante (AA) mediante los métodos de Folin-Ciocalteau y DPPH, respectivamente. Se evalúo la estabilidad del CFT y AA durante el almacenamiento. La EASU aumentó 33.93 % el rendimiento en los extractos con respecto a EC. La mayor concentración de CFT (P ≤ 0.05) se obtuvo mediante EABU (10.32 mg EAG/ms) y para AA mediante EC (19.43 mg ET/g ms). El modelo cinético de pseudo-segundo orden ajustó adecuadamente las cinéticas experimentales. La constante de velocidad (k) de CFT más alta fue de 0.016 g ms/mg EAG·min para la EASU, siendo esta técnica la que demostró una disminución significativa de AA con respecto al tiempo de extracción. Los CFT de los extractos obtenidos mediante EABU, EASU y EC (3.7 mg EAG/g ms, 4.4 mg EAG/g ms y 7.2 mg EAG/g ms, respectivamente), al igual que la AA se mantuvieron estables y sin cambios significativos (P ≥ 0.05) durante los 34 d de almacenamiento, mostrando nuevamente la ventaja de utilizar la técnica extractiva de ultrasonidos, en función del tiempo.


Abstract: Conventional phytochemicals extraction methods have shown low yields or very long processing times for obtaining. The ultrasound offers alternatives to increase the yields of plant extracts. The objective of this work was to evaluate the effect of three extraction methods on the yield, phenolic compound composition, antioxidant activity and stability of Plectranthus amboinicus (oregano) leaf extracts. The extraction methods used were: conventional heat-assisted extraction (CE), ultrasound water bath assisted (UBAE) and ultrasound probe assisted extraction (UPAE). A 1:10 (w/v) oregano:ethanol ratio was used at 35 ± 2 °C. Yields were calculated as extract dry matter (% ms). A pseudo-second-order model was used to fit the experimental extraction curves of the three methods and obtain the kinetic parameters. Total phenolic compounds (TPC) and antioxidant activity (AA) were determined by Folin-Ciocal-teau and DPPH methods, respectively. The stability of TPC and AA was evaluated during storage. UPAE increased 33.93 % yield in extracts concerning CE. The highest concentration of CFT (P ≤ 0.05) was obtained by UBAE (10.32 mg EAG/ms) and for AA by CE (19.43 mg ET/g ms). The pseudo-second-order kinetic model adequately fitted the experimental kinetics. The highest TPC rate constant (k) was 0.016 g ms/mg EAG·min, for UPAE, this technique being the one that demonstrated a significant decrease in AA with respect to extraction time. The TPC of the extracts obtained by UBAE, UPAE and CE (3.7 mg EAG/g dms, 4.4 mg EAG/g dms and 7.2 mg EAG/g ms, respectively), as well as the AA remained stable and without significant changes (P ≥ 0.05) during the 34 d of storage, again showing the advantage of using the ultrasound extractive technique, as a function of time.

2.
Artigo | IMSEAR | ID: sea-194776

RESUMO

Siddha Medicine (Tamil Citta- or Tami?-maruttuvam) is a system of traditional medicine originating in Tamil Nadu in South India. The drugs used by the Siddhars could be classified into three groups: Thaavaram, Thaathu and Jangamam seeraga chooranam is a drug under the category of Thaavaram. It is a poly herbal formulation which is mentioned in the text Pullipanivaithyam 500 which has been therapeutically used for Pithanoigal, Kirukirupu, Vaanthi, Mayakkam, Ajeeranam, Kaangai, Veppam.Siddha system emphasis mainly on healthy long life by preventing ageing and degenerative disease with medicines having antioxidant activity. Even though this drug has been used based on traditional knowledge no scientific work has been done to evaluate the antioxidant properties of Seeraga choornam based on various in vitro assays. The study result confirmed that the drug Seeraga choornam has promising therapeutic antioxidant activity when compared with the standard drug. This research work can help for medical practitioners to use this polyherbal compound for the treatment of cancer.

3.
Artigo em Chinês | WPRIM | ID: wpr-845480

RESUMO

Objective To explore the effect of Cortex Eucommiae (CE) extract on oxidative stress markers of brain aging mice. Methods Brain aging mice model was made via subcutaneously administered D-galactose. The ethanol extract of CE was intra-gastrically administered to the model mice. Apoptosis ratio of brain cells of mice was determined by a flow cytometry to evaluate the anti-aging function of CE extract. A series of biomarkers related to oxidation, including malonyldialdehyde (MDA), superoxide dis-mutase (SOD), protein carbonyl (PCO), and nitric oxide (NO) in serum of mice were determined by ELISA. Results Compared with the model mice, the apoptosis ratio of brain cells in the CE extract group decreased significantly (P<0.01). ELISA test results showed that,compared with the normal group, NO and SOD levels in serum of CE extract group were significantly higher (P<0.01). Compared with the model group, MDA and PCO levels in serum of CE extract group were significantly lower (P<0.01), and SOD level was obviously higher (P<0.01). Conclusion The CE extract might play the role of brain anti-aging by the effective attenuation of oxidative damage.

4.
Artigo em Chinês | WPRIM | ID: wpr-605618

RESUMO

Objective To explore the effect of Cortex Eucommiae(CE)extract on oxidative stress markers of brain aging mice. Methods Brain aging mice model was made via subcutaneously administered D-galactose. The ethanol extract of CE was intra?gastrically administered to the model mice. Apoptosis ratio of brain cells of mice was determined by a flow cytometry to evaluate the an?ti-aging function of CE extract. A series of biomarkers related to oxidation,including malonyldialdehyde(MDA),superoxide dis?mutase(SOD),protein carbonyl(PCO),and nitric oxide(NO)in serum of mice were determined by ELISA. Results Compared with the model mice,the apoptosis ratio of brain cells in the CE extract group decreased significantly(P<0.01). ELISA test results showed that,compared with the normal group,NO and SOD levels in serum of CE extract group were significantly higher(P<0.01). Compared with the model group,MDA and PCO levels in serum of CE extract group were significantly lower(P<0.01),and SOD level was obviously higher(P<0.01). Conclusion The CE extract might play the role of brain anti-aging by the effective attenuation of ox?idative damage.

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