Synthesis and evaluation of antibacterial and antitumor activities of new galactopyranosylated amino alcohols.

Three series of d-galactose derivatives linked to a lipophilic aminoalcohol moiety were synthesized and their antibacterial activity was evaluated against Mycobacterium tuberculosis and representative species of Gram positive and Gram negative bacteria. Five out of the thirteen tested compounds displayed activity against M. tuberculosis, with a minimal inhibitory concentration (MIC) of 12.5 µg/mL and seven compounds were active against the four bacterial strains tested. The best results were obtained for amino alcohols 10 and 11 against Staphylococcus epidermidis (MIC = 2 µg/mL). The antitumor activity was evaluated against three tumor cell lines (MCF-7, HeLa and MO59J) and compared to the normal cell line GM07492A. The results showed that the lowest IC50 values were observed for the amino alcohol 16 against MCF-7 (11.9 µM) and MO59J (10.0 µM).

Antiproliferative activity of Solanum lycocarpum alkaloidic extract and their constituents, solamargine and solasonine, in tumor cell lines.

Natural products are some of the important sources of new anticancer drugs. The Brazilian flora is considered one of the most diverse in the word, although not many large-scale pharmacological and phytochemical studies have been conducted to date. With this in mind, in the present study we evaluated the antiproliferative activity of Solanum lycocarpum fruit glycoalkaloid extract (SL) and its major compounds, solamargine (SM) and solasonine (SS), against different tumor cell lines: murine melanoma (B16F10), human colon carcinoma (HT29), human breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), human hepatocellular liver carcinoma (HepG2) and human glioblastoma (MO59J, U343 and U251). The antiproliferative activity was evaluated using XTT assay and results were expressed as IC50. The most pronounced antiproliferative activity was observed for SM, with IC50 values ranging from 4.58 to 18.23 µg/mL. The lowest IC50 values were observed against HepG2, being 9.60 µg/mL for SL, 4.58 µg/mL for SM and 6.01 µg/mL for SS. Thus, SL, SM and SS demonstrated antiproliferative activity against the tumor cell lines tested, and were most effective against the HepG2 cell line.

Evaluation of a Propolis Water Extract Using a Reliable RP-HPLC Methodology and In Vitro and In Vivo Efficacy and Safety Characterisation.

Since the beginning of propolis research, several groups have studied its antibacterial, antifungal, and antiviral properties. However, most of these studies have only employed propolis ethanolic extract (PEE) leading to little knowledge about the biological activities of propolis water extract (PWE). Based on this, in a previous study, we demonstrated the anti-inflammatory and immunomodulatory activities of PWE. In order to better understand the equilibrium between effectiveness and toxicity, which is essential for a new medicine, the characteristics of PWE were analyzed. We developed and validated an RP-HPLC method to chemically characterize PWE and PEE and evaluated the in vitro antioxidant/antimicrobial activity for both extracts and the safety of PWE via determining genotoxic potential using in vitro and in vivo mammalian micronucleus assays. We have concluded that the proposed analytical methodology was reliable, and both extracts showed similar chemical composition. The extracts presented antioxidant and antimicrobial effects, while PWE demonstrated higher antioxidant activity and more efficacious for the most of the microorganisms tested than PEE. Finally, PWE was shown to be safe using micronucleus assays.

Assessment of the genotoxicity and antigenotoxicity of (+)-usnic acid in V79 cells and Swiss mice by the micronucleus and comet assays.

Usnic acid is one of the most common and abundant metabolites found in various lichen genera, which are important sources of biologically active compounds. The aim of this study was to evaluate the genotoxic and antigenotoxic potential of (+)-usnic acid (UA) by the micronucleus and comet assays in V79 cell cultures and Swiss mice. For assessment of genotoxicity, V79 cells were treated with 15, 30, 60, and 120µg/mL UA, established based on clonogenic efficiency cytotoxic assay. Swiss mice were treated with UA doses of 25, 50, 100, and 200mg/kg body weight. The same concentrations of UA were combined with methyl methanesulfonate (MMS) for evaluation of antigenotoxicity. The in vitro results demonstrated that UA induced DNA damage at concentrations of 60 and 120µg/mL in the comet assay. However, no genotoxic effect was observed in the micronucleus test using V79 cells at the concentrations tested. No genotoxic effects were observed for the different UA treatments in in vivo test system. Combined administration of UA and MMS significantly reduced the frequencies of micronuclei and DNA damage in vitro and in vivo when compared to treatment with MMS alone. Although the mechanisms underlying the protective effect of UA are not completely understood, the antioxidant activity of this metabolite may explain its protective effect against MMS-induced genotoxicity.