Comparison of antioxidant and antimicrobial activities of extracts obtained from Salvia glutinosa L. and Salvia officinalis L.

Antioxidant and antimicrobial activities as well as total phenols and flavonoids contents of Salvia glutinosa L. (glutinous sage) and Salvia officinalis L. (sage) extracts were studied. Methanol and aqueous ethanol (70% v/v) were used for extraction of bioactive compounds, both in the presence and the absence of ultrasound, from herb and the spent plant material remaining after the essential oil hydrodistillation. The ratio of plant material to extracting solvent was 1:10 g/ml. Antioxidant and antimicrobial activities of the extracts were found to depend on the type of plant material and the extraction conditions. The plant materials from which essential oil had been recovered were proven to be valuable raw materials for making various herbal preparations

Antioxidant activity, the content of total phenols and flavonoids in the ethanol extracts of Mentha longifolia (L.) Hudson dried by the use of different techniques

In this study, we have examined the yield of extracted substances obtained by means of extraction using 70 % ethanol (v/v), the content of total phenols and flavonoids, as well as the antioxidant activity of the extracts obtained from the samples of the herbs dried by means of different techniques. Wild mint Mentha longifolia (L.) Hudson was dried naturally in a laboratory oven at a temperature of 45 °C and in an absorptive low temperature condensation oven at 35°C. The highest yield of extracts was obtained from the naturally dried herbs and the lowest from the herbs dried in the low temperature condensation drying oven. The content of total phenols and flavonoids was determined by spectrophotometric methods with an FC reagent and by the complexation reaction with aluminium-chloride, respectively. The extract of the naturally dried herbs had the highest overall content of phenols (113.8±2.0 mg of gallic acid/g of the dry extract) and flavonoids (106.7±0.3 mg of rutin/g of the dry extract). The highest antioxidant activity determined by the FRAP and DPPH assay was determined in the extracts obtained from naturally dried herbs (2.76±0.15 mmol Fe2+/mg of the dry extract and EC50=0.022±0.001 mg/ml), while the lowest was obtained from the extracts of herbs dried in the laboratory oven (1.13±0.11 mmol Fe2+/mg of the dry extract and EC50=0.033±0.001 mg/ml). The HPLC-DAD analysis result show that the greatest content of phenolic compounds show extract obtained from naturally dried plant material. The dominant phenolic component in the all extracts is Kaempferol 3-O-glucoside. The content of all phenolic compound strongly depend on the drying conditions

Chemical, antioxidant and antimicrobial analysis of the essential oil and extract of artemisia alba tura

This study examines the essential oil and the ethanol extract of Artemisia alba Turra herb, in terms of chemical composition, antioxidant and antimicrobial activities in order to select the active pharmacological isolate for making phytopreparation from the group of bitter aromatics and/or bitter liqueurs. Chemical composition of the essential oils and volatile fractions of the extract was determined by GC-FID/GC-MS and non-volatile fractions of the extract by HPLC. The content of total phenolics and flavonoids in the extracts was determined by Folin-Ciocalteu reagent and aluminum chloride, respectively. The antioxidant activity of isolates was tested by FRAP and DPPH tests and the antimicrobial by microdilution method. Major constituents in the essential oil were camphor, artemisia ketone and 1,8-cineole (23.7%, 15.2% and 14.1%, respectively), and in the volatile fraction of the extract, scopoletin (14.0%) and corymbolone (10.3%). The main components in non-volatile fraction of the extract were kaempferol 3-O-(6 ''-O-malonylglucoside)- 7-O-rhamnoside, chlorogenic acid and rutin (16.1%, 11.4% and 9.5% respectively). The content of total phenolics in the extract, expressed as gallic acid was 77.18 mg/g and flavonoids, expressed as rutin 53.80 mg/g of dry extract. Extract exhibited stronger antioxidant activity than essential oil and better antimicrobial activity on a larger number of tested microorganisms

Direct ultrasound-assisted extraction and characterization of phenolic compounds from fresh houseleek (Sempervivum marmoreum L.) leaves

The effects of ultrasound power and frequency on the yield of total extractive substances (TES), total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AOA) of fresh houseleek leaves extracts obtained by direct ultrasound-assisted extraction (DUAE) were studied. Preliminary extraction of plant material was performed using methanol, acetone and 2-propanol by Soxhlet extraction. It was found that maximum TES yield could be obtained by methanol extraction (2.91±0.02), followed by acetone and 2-propanol with a TES yield of 2.32±0.01 and 2.01±0.03 g per 100 g of fresh plant material, respectively. In the fresh houseleek leaves extracts obtained by DUAE and methanol as the chosen solvent, TPC, TFC and AOA were in the ranges of: 40.5–85.9 mg gallic acid/g dry extract, 12.7–19.3 mg rutin/g dry extract and 24.6–108.2μg/ml, respectively. The results showed that the increase in the ultrasound power and extraction time have positive and significant (p < 0.05) effects on the TPC, TFC and AOA, while the increase in the ultrasound frequency leads to a decrease in the TPC, TFC and AOA of the extracts. A chromatographic analysis of crude extract identified the following: kaempferol 3-O-(6’’-O-malonylglucoside)- 7-O-glucosyde, kaempferol 3-O-glucoside-7-O-rhamnoside, luteolin 5-O-(6’’-O-malonylglucoside), kaempferol 3-O-(6’’-O-acetylglucoside)-7-O-rhamnoside, genkwanin 5-O-glucoside, luteolin 5-O-(6’’-O-malonylglucoside), kaempferol 3-O-(6’’-O-malonylglucoside), kaempferol 3-O-rhamnoside, quercetin, genkwanin 4’-O-glucoside and hyperoside. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172047

JSCS–3742 Original scientific paper

Comparative screening of the anti-oxidant and antimicrobial activities of Sempervivum marmoreum L. extracts obtained by various extraction technique