ANTIADHESIVE AND ANTIBIOFILM POTENTIAL OF SUBCRITICAL WATER EXTRACTS DERIVED FROM MASHROOM INONOTUS OBLIQUUS

Mushroom Inonotus obliquus has been traditionally used in China, Korea, Russia and in most Baltic countries as health promoting remedy. The study was designed to investigate antimicrobial activity of subcritical water extracts derived from mushroom I. obliquus originating from Mongolia (IM) and from mountain Vlasina, Serbia (IS), including their antiadhesive and antibiofilm capability. Antimicrobial potential of subcritical water extracts was tested by microdilution method. The antiadhesive and antibiofilm abilities were monitored using Gram positive bacteria Listeria monocytogenes, Enterococcus faecalis and Staphylococcus aureus, as well as Gram negative Salmonella enteritidis, Escherichia coli and Pseudomonas aeruginosa. The most significant biofilm production was observed in E. faecalis (the third category) and S. aureus (the second category). It was noticed that IS and IM were able to provide up to 90% of E. faecalis and S. aureus adhesion and biofilm reduction, i.e. to decrease the ability of these two bacteria to adhere and form a biofilm (the first or almost zero category, after contact with extracts). In general, Gram positive bacteria appeared as more susceptible to the presence of both tested subcritical water extracts (MBC - 20 mg/mL in all experiments). According to the obtained MIC values, IM (5 mg/mL, 2.5 mg/mL, 2.5 mg/mL) exhibited a stronger effect than IS (10 mg/mL, 5 mg/mL, 5 mg/mL) on L. monocytogenes, E. faecalis and S. aureus, respectively. This study revealed that tested subcritical I. obliquus water extracts are very effective in preventing the formation of biofilms, especially those of selected Gram-positive bacteria. This discovery could be very useful in combating biofilms, taking into account all the problems and dangers that they brin

Kinetics and modeling of the extraction of flax seed oil (Linum usitatissimum L.) by supercritical carbon dioxide

The object of this study is supercritical carbon dioxide extraction of flax seed oil (Linum usitatissimum L.) at the pressures of 30, 40 and 50 MPa, temperatures of 47 and 52 °C, extraction time of 4 h, special flows of solvent of 8.8 kg/(kg h), and particle size fractions of grinding material of 0.16-0.315, 0.315-0.80 and 0.80-2.00 mm. Supercritical fluid extraction (SFE) of the flax seed oil on the laboratory scale, with the special interest in the influence of the extraction pressure, temperature, extraction time, and grinding of ground material on the overall yield of the flax seed oil was investigated. Experimental results of the oil yields were compared with the data obtained by the mathematical model of Hong et al. [I.K. Hong, S.W. Rho, K.S. Lee, K.P. Yoo, Korean J. Chem. Eng. 7 (1990) 40], presented in the literature

Determination of optimal parameters of basil supercritical fluid extraction by response surface methodology

The supercritical fluid extraction of aroma compounds from basil (Ocimum basilicum L.) was studied. Response surface methodology was used to optimize the parameters of the process. Full factorial design was applied to evaluate the effects of two independent variables (pressure and temperature) on the extraction yield and linalool yield. From the response surface plots, pressure and temperature exhibited independent and interactive effect on the extraction yield. The optimal conditions to obtain the highest extraction yield (1.91%) of O. basilicum were the pressure of 29.7 MPa and temperature of 59.2oC, whereas the highest yield of linalool (1.998 g•kg-1) was obtained at the pressure of 20 MPa and temperature of 40oC. The experimental values agreed with the predicted ones, indicating suitability of the response surface methodology for optimizing the extraction process. [Projekat Ministarstva nauke Republike Srbije, br. TR 31013

Determination of extraction conditions of Ginkgo biloba L. leaves by supercritical CO2 using response surface methodology

The effects of process parameters on the extraction of Ginkgo biloba L. leaves with supercritical carbon dioxide were investigated. The investigated parameters include particle size (mean particle diameter 0.19, 0.467 and 1.009 mm), solvent flow rate (1.5810-3, 3.2210-3 and 4.1610-3 kg CO2/min) and pressure (100-300 bar), which were obtained by the response surface methodology (RSM) under the following condition ranges: temperature 40-50-60ºC, pressure 100-140-180 bar and extraction time of 2-3-4 h at the flow rate of 3.2210-3 kg/min. Based on the experimental results of kinetics of Ginkgo biloba leaves extraction with supercritical carbon dioxide, modeling of the extraction system of Ginkgo biloba-supercritical CO2 was done. Two mathematical models (Reverchon-Sesti Osseo and Sovová) were applied to correlate the experimental data. RSM was applied to optimize the process parameters of supercritical carbon dioxide extraction of Ginkgo biloba L. leaves. A second-order polynomial response surface equation was developed indicating the effect of variables on Ginkgo biloba extraction yield. The statistical analysis of the experiment indicated that pressure (X1), extraction time (X3), the quadratic of temperature (X22), and the interaction between pressure and extraction time (X1X3), show significant effect on the extraction yield. The results showed that the data were adequately fitted into the second-order polynomial model. It was predicted that the optimum extraction process parameters within the experimental ranges would be the extraction temperature of 52.7ºC, the pressure of 184.4 bar, and the extraction time of 3.86 h. Under these conditions, the predicted extraction yield is 2.39% (g/100 g drug)

Basil (Ocimum basilicum L.) essential oil and extracts obtained by supercritical fluid extraction

The extracts obtained from sweet basil (Ocimum basilicum L.) by hydrodistillation and supercritical fluid extraction (SFE) were qualitative and quantitative analyzed by GC-MS and GC-FID. Essential oil (EO) content of basil sample, determined by an official method, was 0.565% (V/w). The yields of basil obtained by SFE were from 0.719 to 1.483% (w/w), depending on the supercritical fluid (carbon dioxide) density (from 0.378 to 0.929 g mL-1). The dominant compounds detected in all investigated samples (EO obtained by hydrodistillation and different SFE extracts) were: linalool, as the major compound of basil EO (content from 10.14 to 49.79%, w/w), eugenol (from 3.74 to 9.78%) and ä-cardinene (from 3.94 to 8.07%). The quantitative results of GC-MS from peak areas and by GC-FID using external standard method involving main standards, were compared and discussed. [Projekat Ministarstva nauke Republike Srbije, br. TR 31013

Free radical scavenging activity, total phenolic and flavonoid contents of mulberry (Morus spp. L., Moraceae) extracts

Mulberry (Morus spp. L., Moraceae) fruits, leaves, bark and branch have been used in traditional medicine as diuretic, hypoglycemic and hypotensive. The mechanism of their effects is correlated with the content of active components. Objective of this work was to evaluate and compare antioxidant properties of different extracts of two Morus species growing in Serbia: Morus alba L. (white mulberry) and Morus nigra L. (black mulberry). Potential antioxidant activity, content of antioxidant compounds (phenolics and flavonoids) and radical scavenging capacity, tested by DPPH method, were evaluated. The phenolic and flavonoid composition of different Morus extracts was determined by the HPLC method. The extracts prepared from fruits, leaves and roots of M. alba and M. nigra exhibited different characteristics. The highest extraction yield was achieved by M. alba leaves extraction (23.40%). M. nigra roots extract shown the highest total phenolics (186.30 mg CAE/g), while highest total flavonoids content (67.37 mg RE/g) was determined for M. nigra leaves extracts. In addition, black mulberry leaves extracts with the highest antioxidant activity had the highest phenolic acids contents. The dominant phenolic components in the samples were rutin and chlorogenic acid. All investigated mulberry dry extracts shown high content of phenolic compounds and significant antioxidant activity. This work contributes to knowledge of the antioxidant properties of Morus species. The obtained results may be useful in the evaluation of new dietary supplements and food products

Optimization of the Ocimum basilicum L. extraction process regarding the antioxidant activity

The levels of input variables (temperature and extraction solvent) that optimize a particular response (total phenols content, total flavonoids content and antioxidant activity) of the Ocimum basilicum L. extraction process were determined by the response surface methodology (RSM). The influence of theextraction temperature on extraction process was investigated in the range from 33.8ºC to 76.2ºC, as well as of extraction solvent ethanol, in the range of concentrations from 21.7% to 78.3%. For the preparation of basil dry extract, characterized with minimal IC50 value, the calculated optimal values of temperature and ethanol concentration were: 75.33ºC and 73.66% (w/w). [Projekat Ministarstva nauke Republike Srbije, br. TR 31013