Acacia aroma, native plant from San Luis, Argentina, is commonly used as antiseptic and for healing of wounds. The present study was conducted to investigate the in vitro cytotoxicity and genotoxicity of hot aqueous extract (HAE) and ethanolic extract (EE) of A. aroma. The cytotoxic activity was assayed by neutral red uptake assay on Vero cell. Cell treatment with a range from 100 to 5000 μg/mL of HAE and EE showed that 500 μg/mL and 100 μg/mL were the maximum noncytotoxic concentrations, respectively. The CC50 was 658 μg/mL for EE and 1020 μg/mL for HAE. The genotoxicity was tested by the single-cell gel electrophoresis comet assay. The results obtained in the evaluation of DNA cellular damage exposed to varied concentrations of the HAE showed no significant genotoxic effect at range of 1–20 mg/mL. The EE at 20 mg/mL showed moderate genotoxic effect related to the increase of the DNA percentage contained in tail of the comet; DNA was classified in category 2. At concentrations below 5 mg/mL, the results of cytotoxicity and genotoxicity of aqueous and ethanolic extracts of Acacia aroma guarantee the safety at cell and genomic level. However further studies are needed for longer periods including animal models to confirm the findings.

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The natural products derived from medicinal plants have proven to be an abundant source of compounds with antibacterial activity. The antibacterial activity of extracts of Azorella trifurcata and M. echegarayii was evaluated against strains of Staphylococcus aureus ATCC 43300, Pseudomonas aeruginosa ATCC 27853, Listeria monocytogenes CLIP 74902 and Escherichia coli ATCC 35218. Organic extracts were prepared using n-hexane, mixtures of n-hexane and ethyl acetate of increasing polarity and a mixture of ethyl acetate and methanol on flash chromatography. All the extracts of A. trifurcata showed antibacterial effects against grampositive bacteria (CIM between 0.5 and 2 mg/ml). Four extracts (100% n-hexane, 40:60/50:50 acetate: nhexane, 70:30 ethyl acetate: n-hexane and 2:98 methanol: ethyl acetate) of A. trifurcata showed antibacterial activity against gram-negative bacteria. M. echegarayii 2:98 methanol: ethyl acetate was active against all gram-negative and gram-positive bacteria (CIM between 1 and 2 mg/ml). The values of MBC of the extracts assayed were one or two times higher than corresponding MIC values. The discovery of organics extracts with antibacterial properties could contribute to the treatment of bacterial infections.

Solid and liquid media supplemented only with a cyanobacterial extract (CE) and free of fetal calf serum (FCS), blood, and its derivatives support the growth of Helicobacter pylori. A total of 11 strains of H. pylori isolated from gastric biopsy samples were successfully subcultured in Mueller-Hinton agar supplemented with 0.4% CE. When this medium was used for primary isolation of H. pylori, a low isolation rate (30%) was observed because of the abundant growth of contaminants. The growth kinetics of eight isolates and H. pylori reference strain NCTC 11638 in Mueller-Hinton broth (MHB) supplemented with 0.7% CE were estimated by use of growth parameters, and the results were compared with those obtained with MHB-5% FCS. For four strains the cellular concentrations obtained with CE were statistically higher (P < 0.05) than those obtained with FCS, and in some cases these values were similar to the highest values reported in the literature. Depending on the strain, the specific growth rates obtained with CE were similar to or increased compared with those obtained with FCS. The replacement of FCS by CE in H. pylori cultures would facilitate the retrieval of cultures with high cellular densities as a source of cellular and extracellular proteins free of serum. Also, CE has advantages over conventional supplements, such as easier conservation and compliance with the pressing tendency at present to avoid the use of products derived from animals.