Putative application of Najas marina L. extracts as a source of bioactive compounds and their antioxidant, antimicrobial, antibiofilm, and genotoxic properties.

In this research paper, the total phenols (TP), flavonoids (TF), and tannins (TT) content in the acetone and ethyl acetate extracts of Najas marina L. and the identification and quantification of phenolic acids and flavonoids from the ethyl acetate extract were performed. Antioxidant, antimicrobial, and antibiofilm properties of the mentioned extracts were investigated in vitro. The genotoxic potential was analyzed in cultured human peripheral blood lymphocytes (PBL). The TP and TF content was higher in the ethyl acetate extract, dominated by quercetin (172.4 µg mg-1) and ferulic acid (22.74 µg mg-1), while the TT content was slightly higher in the acetone extract. Both extracts tested showed limited antioxidant effects compared to ascorbic acid. The strongest antibacterial activity was observed with Gram-positive bacteria, particularly Staphylococcus aureus (MIC and MMC at 0.31 mg ml-1) and S. aureus ATCC 25923 (MIC at <0.02 mg ml-1), while antifungal activity was limited. Both extracts tested showed better activity on preformed biofilms. Acetone extract had no genotoxic activity but showed significant genoprotective activity against mitomycin C-induced DNA damage in cultured PBLs. Results of our research demonstrate the potential for the development of plant-based antibacterial and biofilm agents.

Methanol extracts of Teucrium arduini L. and Teucrium flavum L. induce protective effect against mitomycin C in human lymphocytes in vitro.

The study was designed to evaluate antigenotoxic effect of methanol Teucrium arduini and Teucrium flavum extracts against mitomycin C (MMC)-induced chromosome and DNA damage in vitro. Cytokinesis-block micronucleus (CBMN) and comet assays were used to investigate effect of plant extracts in different concentrations (125, 250, 500 and 1000 µg/mL) on human peripheral blood lymphocytes (PBLs). The obtained results showed that the all tested concentrations of T. arduini and the highest concentration of T. flavum significantly reduced the MMC-induced micronucleus (MN) frequency in comparison to positive control (only MMC). There were significantly negative correlations between the extracts concentrations and MN frequencies (Pearson, r = -0.905, p = 0.0001 for T. arduini; r = -0.861, p = 0.0001 for T. flavum). The extracts of both plants further lowered the MMC-decreased nuclear division index (NDI) in a dose dependent-manner (Pearson, r = -0.837, p = 0.001 for T. arduini; r = -0.598, p = 0.040 for T. flavum), but significantly only in the highest concentration (1000 µg/mL). Comet assay showed that extracts reduced MMC-increased genetic damage index (GDI), significantly in the concentrations of 500 and 1000 µg/mL, in comparison with positive control. Based on our results, it can be concluded that methanol T. arduini and T. flavum extracts possess protective proapoptotic and antigenotoxic effect which is indication of their medicinal relevance and use in treatment.

Comparative study of the genotoxic activity of Artemisia vulgaris L. and Artemisia alba Turra extracts in vitro.

In this study, the genotoxic activity of acetone and aqueous extracts of two species of genus Artemisia (Artemisia vulgaris L. and Artemisia alba Turra), and possible role of their polyphenolic composition in the observed activities were investigated. Polyphenolic contents were evaluated by high-performance liquid chromatography (HPLC-PDA), while the genotoxic activity was tested using cytokinesis block micronucleus (CBMN) assay on human peripheral blood lymphocytes (PBLs) in vitro. HPLC-PDA showed that both A. alba extracts were richer in polyphenolic contents than A. vulgaris extracts. The acetone A. alba extract was the richest of polyphenolic content where we detected six phenolic acids and two flavonoids. CBMN assay showed that aqueous extract of A. vulgaris significantly increased micronucleus (MN) frequency in the PBLs treated with all tested concentrations (10, 50, 100, and 250 µg/mL), while A. alba did not significantly affect the mean MN frequency. Further, both acetone extracts were genotoxic in all tested concentrations, except the lowest tested (10 µg/mL) of A. alba. All tested extracts affected the nuclear division index (NDI) except the aqueous A. alba extract (p < 0.05). Based on our results, we can conclude that both acetone and aqueous A. vulgaris extracts and A. alba acetone extract were genotoxic in PBLs in vitro. A. alba aqueous extract was not genotoxic and cytotoxic in tested concentrations. We suggest that the aqueous extract of A. alba can be used in treatment, which has been confirmed by traditional medicine, but with a high dose of caution and not in high concentrations.

The Health Promoting Effects of the Fruiting Bodies Extract of the Peppery Milk Cap Mushroom Lactarius piperatus (Agaricomycetes) from Serbia.

Antioxidant, antimicrobial, genoprotective, anticancer, and neuroprotective potential of acetone extract of the fruiting bodies of the edible mushroom Lactarius piperatus was studied. The antioxidant activity was evaluated using different methods (DPPH radical scavenging, superoxide anion radicals scavenging, reducing power assay, and determination of total phenolic compounds). The microdilution method was used to reveal the antimicrobial potential. The genoprotective potential was determined by Comet assay. Cytotoxic activity was tested using MTT. The capacity of the extract to inhibit acetylcholinesterase was used for determining its neuroprotective potential. The received results show that L. piperatus extract possessed potent health enhancing effects. In the antioxidant activity, IC50 was 33.97 µg/mL for DPPH radicals scavenging and 22.52 µg/mL for superoxide anion radicals scavenging, whereas the absorbance for the reducing power was from 0.0510 to 0.1451. The total content of phenolic compounds in the extract was 5.08 µg PE/mg. The testing of the antimicrobial activity showed that MIC values were from 0.039 to 10 mg/mL. For Comet assay, all concentrations of extract increased the GDI values from 0.46 ± 0.05 to 0.99 ± 0.31. L. piperatus extract expressed relatively strong cytotoxic activity with IC50 values ranging from 37.83 to 65.94 µg/mL. Finally, the percentage of inhibition of acetylcholinesterase activity of tested extract was within the range 16.75-44.35%. Our results imply that the acetone extract of L. piperatus has rather strong antioxidant, antimicrobial, genoprotective, anticancer, and neuroprotective effects; thus this mushroom represents healthy food that could be used in the pharmaceutical industry and to prevent various diseases.

Genotoxic and cytotoxic properties of two medical plants (Teucrium arduini L.and Teucrium flavum L.) in relation to their polyphenolic contents.

A large number of species belonging to the genus Teucrium are used in pharmacy and traditional medicine for the treatment of different diseases. This study aimed to evaluate the polyphenolic composition as well as genotoxic and cytotoxic effects of methanolic extracts from T. arduini and T. flavum, two native species found in Montenegro. We determined the total phenolic and flavonoid contents of these plants using spectrophotometric methods; the qualitative content of polyphenolic compounds was investigated by high-performance liquid chromatography (HPLC). Genotoxicity in cultured human lymphocytes was measured in the cytokinesis-block micronucleus assay (CBMN) and comet assay in the range between 125 and 1000 µg/mL. Cytotoxicity was assessed by the MTT viability assay in normal human MRC-5 fibroblasts and MDA-MB-231 breast carcinoma cells. The content of total phenolics and flavonoids in T. arduini extract was higher than in T. flavum (200.35 mg GA/g vs. 171.08 mg GA/g; 96.32 mg RU/g vs. 78.14 mg RU/g). The polyphenolic composition of both extracts was qualitatively similar and eight phenol compounds were identified. The most commonly present phenol was caffeic acid and among four flavonoids, the most common was quercetin. Both plant extracts were genotoxic in both the CBMN and comet assays at concentrations of 250, 500 and 1000 µg/mL. After 72 h of exposure, the extracts of T. arduini and T. flavum were found to induce cytotoxicity in MRC-5 fibroblasts but not in MDA-MB-231 breast cancer cells. The results suggest that the constituents of both plant species are genotoxic and cytotoxic, therefore these extracts warrant additional evaluation to be safely applied in humans.

Polyphenolic contents of Teucrium polium L. and Teucrium scordium L. associated with their protective effects against MMC-induced chromosomal damage in cultured human peripheral blood lymphocytes.

Teucrium species have been used in traditional medicine for treatment of different diseases. The aim of this study was to investigate polyphenolic contents by high-performance liquid chromatography (HPLC), and the genotoxic effect of methanolic extracts of Teucrium polium and Teucrium scordium using the cytokinesis-block micronucleus (CBMN) assay on human peripheral blood lymphocytes (PBLs) from healthy donors. The HPLC  analysis  showed that extracts consist of phenolic acid (gallic, vanillic, caefic, chlorogenic, p-coumaric, sinapic) and flavonoids (catechin, rutin, myricetin, luteolin, quercetin and apigenin). Cultures were treated with extracts of both plants separately and in combinations with mitomycin C (MMC). In separate treatments, both herbal extracts significantly induced micronucleus (MN) frequency only at the highest concentrations. All concentrations of T. scordium , except the lowest, and all concentrations of T. polium extracts in combined treatment with MMC significantly reduced the frequency of MN. The extract of T. polium did not significantly aefct the nuclear division index (NDI), whereas T. scordium in higher concentrations, separately and in combined treatment with MMC, significantly decreased the NDI value. Our results suggest that both herbal extracts in combination with MMC have antimutagenic (T. polium) and proapoptotic effects (T. scordium), which indicates their protective effects in PBLs.