Assessment of the Antioxidative Potential of Rosmarinus officinalis L. (Lamiaceae) Irrigated with Static Magnetic Field-Treated Water

Abstract Phenolic compounds are one of the main groups of secondary metabolites in plants and are known for their antioxidant activity. Rosmarinus officinalis L. (rosemary) contains different phenolic compounds including carnosol, carnosic acid and rosmarinic acid. In Cuba, rosemary cultivation is limited because it is difficult to propagate and has a low yield. As a result, it was removed from the Herbal Medicine National Formulary. However, the National Public Health System has a strong interest in rosemary because of its value as a natural antioxidant medicine. Irrigation with water treated with a static magnetic field (SMF) is a possible strategy to increase rosemary yield. This technology has been applied to accelerate plant growth and increase crop quality. The aim of this study was to evaluate the content of phenolic compounds and antioxidant activity in aqueous leaf extracts from plants irrigated with SMF-treated water in comparison to control plants. Significant differences in phenolic content and antioxidant activity were observed between aqueous extracts of control plants and plants irrigated with SMF-treated water. Therefore, irrigation with SMF-treated water is a promising technology to improve the cultivation of rosemary as a raw material to obtain pharmaceutical products with high antioxidant activities.

In vitro Antifungal Activity of Plant Extracts, Hydrolates and Essential Oils of Some Medicinal Plants and Control of Cucumber Anthracnose

Aims: This study is aimed to evaluate the in vitro antifungal activity effect of the crude aqueous extract (CAE), hydrolate (HY) and essential oil (EO) of Corymbia citriodora, Cymbopogon citratus, Cymbopogon flexuosus and Curcuma longa against the phytopathogenic fungi Alternaria steviae, Botryosphaeria dothidea, Colletotrichum gloeosporioides and Sclerotium rolfsii, and assess, in situ, the effectiveness of CAE of medicinal plants in reducing the severity of the cucumber anthracnose. Methodology: The EOs and HYs were obtained by hydrodistillation. The CAEs were prepared by the turbolysis method. Mycelial growth of the fungi was measured daily, by the diametrically opposite method. In the in vivo test, the CAEs were sprayed on the cotyledon leaves of healthy cucumber plants with three days after were inoculated with C. lagenarium. The severity of assessment of the disease was based on a scale of notes. Results: The medicinal plants studied showed antifungal activity against all or almost all pathogens. In general, treatment with CAE and HY of C. longa revealed the highest inhibition against the fungi tested. With the exception of the EO of C. longa, the other EOs showed total inhibition against all the fungi and in all the concentrations tested. Compared to control, in in vivo assays CAE of C. citratus presents a potential for control of cucumber anthracnose reducing the severity of the disease. Conclusion: The medicinal plants studied produce compounds associated with antimicrobial activity.