Fatty acid methyl esters (FAMEs) were obtained from vegetable oils of soybean, corn and sunflower. The current study was focused on evaluating the antifungal activity of FAMEs mainly against Paracoccidioides spp., as well as testing the interaction of these compounds with commercial antifungal drugs and also their antioxidant potential. FAMEs presented small IC 50 values (1.86-9.42 μg/mL). All three FAMEs tested showed antifungal activity against isolates of Paracoccidioides spp. with MIC values ranging from 15.6-500 µg/mL. Sunflower FAMEs exhibited antifungal activity that extended also to other genera, with an MIC of 15.6 μg/mL against Candida glabrata and C. krusei and 31.2 μg/mL against C. parapsilosis. FAMEs exhibited a synergetic effect with itraconazole. The antifungal activity of the FAMEs against isolates of Paracoccidioides spp. is likely due to the presence of methyl linoleate, the major compound present in all three FAMEs. The results obtained indicate the potential of FAMEs as sources for antifungal and antioxidant activity.

The antibacterial activity of plant extracts of the Lamiaceae family was evaluated against clinical isolates of multi-resistant Gram-negative bacteria by broth microdilution technique. Promising results were obtained considering that all extracts were active for at least two bacterial species with MIC ranging from 0.5 to 2.0 mg/mL.

Ethanol extract and fractions obtained from aerial parts of Smilax campestris were examined in order to determine their phenolic composition, antioxidant capacity and antifungal activities. High-performance liquid chromatography coupled with DAD analysis indicated that quercetin and rutin were the main phenolic compounds present in butanol fraction and ethanol extract, respectively. The antioxidant activity assessed by the scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radical was significantly more pronounced for the ethanol extract and butanol fraction than that of the commercial antioxidant 2,6-di-tert-butyl-4-methylphenol. The antifungal activity of extract and fractions was investigated by using microdilution method against five Candida and two Cryptococcus yeast strains. Ethanol extract and fractions exhibited antifungal activities against Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, Candida tropicalis and Cryptococcus gattii. This work provides the knowledge of profile and content of flavonoids and their antioxidant and antifungal activities in the extract and fractions of aerial parts of S. campestris.

Bacterial infections cause thousands of deaths in the world every year. In most cases, infections are more serious because the patient is already weakened, and often, the bacteria are already resistant to the antibiotics used. Counterparting this negative scenario, the interest in medicinal plants as an alternative to the synthetic antimicrobial drugs is blossoming worldwide. In the present work, we identified the volatile compounds of ethanol extracts of Melissa officinalis, Mentha sp., Ocimum basilicum, Plectranthus barbatus, and Rosmarinus officinalis by gas chromatography/mass spectrometry (GC/MS). Also was evaluated antimicrobial activity of ethanol extracts against 6 bacteria of clinical interest, and was tested the interaction of these extracts with a commercial antibiotic streptomycin. Phytol was a compound identified in all extracts by GC/MS, being majoritary component in Plectranthus barbatus and Rosmarinus officinalis. The Gram-positive bacteria were more sensitive to ethanol extracts, and Plectranthus barbatus and Rosmarinus officinalis were the most active extracts. Ethanol extracts exhibited a synergetic effect with streptomycin. These results encourage additional studies, in order to evaluate the possibilities of using ethanol extracts of Lamiaceae family as natural source for antibacterial activity.

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The species Rosmarinus officinalis L. is popularly known as rosemary, being widely used in traditional medicine. In the present study, the ethanol extract and fractions obtained from R. officinalis were evaluated for allelopathic and antioxidant activities and determined the content of phenolic compounds. The ethanol extract and fractions showed antioxidant activity in five concentrations tested. Regarding the EC 50 values, the ethanol extract and fractions showed better results than the BHT, reference compound. The EC 50 values obtained for the ethanol extract and fractions could not be correlated directly with the content of phenolic compounds present in the samples. For allelopathic activity, the samples showed heterogeneous effects on growth of hypocotyl and radicle of seeds of lettuce and onion observed at different concentrations (50, 100 and 200 mg/mL). For the radicle onion (Allium cepa), the best results were obtained for the ethanol extract and fractions hexane and dichloromethane, which inhibited growth at all concentrations, and the dichloromethane fraction promoted an inhibition greater than 80.0%, at a concentration of 200 mg/mL. Regarding the onion hypocotyl, the effects were heterogeneous. The results for the growth of radicle and hypocotyl of lettuce seeds (Lactuca sativa) showed that the inhibitory effect was more significant than the stimulatory, when the seeds were treated with the ethanol extract and fractions. Regarding the inhibitory effect, they emphasized the dichloromethane fraction with a 100.0% inhibition, at a concentration of 200 mg/mL. Inhibition of hypocotyl was more significant than the radicle for lettuce seeds. The ethanol extract and dichloromethane fraction had an inhibitory effect, at all concentrations tested. In the search for new antioxidants and allelochemicals of natural origin, the species Rosmarinus officinalis may be a good candidate.Keywords: antioxidant; allelophatic; phenol total; Rosmarinus officinalis.

Efeito da administração oral de extrato etanólico de Rosmarinus officinalis L. (alecrim) no desenvolvimento do Tumor Sólido de Ehrlich Effect of oral administration of the ethanol extract of Rosmarinus officinalis L.

Lamiaceae family has a cosmopolitan distribution, including about 300 genus and 7500 species. Numerous diseases have been related to free radicals overproduction. Antioxidant capacity is related to compounds capable of protecting a biological system against the potentially harmful effect of processes or reactions involving reactive oxygen and nitrogen species. In the present study, the ethanol extracts, obtained by maceration of Melissa officinalis, Mentha sp., Ocimum basilicum, Plectranthus barbatus, and Rosmarinus officinalis were evaluated for antioxidant activity, the total phenolic content was determined, and volatile compounds were identified by Gas Chromatography coupled to Mass Spectrometry (GC-MS). Ethanol extracts of M officinalis, Mentha sp., P. barbatus, and R. officinalis were able to reduce the free radical DPPH with IC50 of 3.81, 11.89, 6.92 and 11.54 μg/ml respectively, presenting better activity than the BHT, used as a standard. However, the ethanol extract of O. basilicum showed low activity and high IC50 value. Total phenols of all extracts ranged from 85.18 to 212.74 μg/ml. The highest phenolic concentration was observed in the ethanol extract of M. officinalis. Analysis of volatile compounds showed the presence of phytol in all extracts, being predominant in P. barbatus and R. officinalis, and also nonadecane and heptadecane in M. officinalis. Fractions obtained from the five species of Lamiaceae also presented antioxidant effect. In the most active fractions were mainly phenolic compounds, such as flavonoids, tannins, and coumarins. These results encourage new studies with these species in order to isolate the compounds responsible for this antioxidant activity so that in the future they can be used as natural antioxidants.