Model uv 1700

Quantitative assessment of the antioxidant activity of red propolis EEP and its fractions were performed according to the methods described in the literature [33 (link), 34 (link)] with a few modifications. The solvent ethanol was used as blank. The inhibition of free radical DPPH by the samples was monitored by measuring the decrease in absorbance of solutions with different concentrations.
The EEP, hexane, chloroform and ethyl acetate fractions of EEP at an initial concentration of 1.0 mg•mL⁻¹ were diluted with ethanol until achieving final concentrations of 25.0, 15.0, 10.0, 5.0 and 2.5 μg•mL⁻¹. Then, 1.0 mL of 0.3 mM DPPH in ethanol was added to 2.5 mL of the EEP and it fractions, and the reaction was left to develop in dark at room temperature (26 °C) over 30 min. The absorbance readings were then performed with a spectrophotometer (Model UV-1700, Shimadzu, Kyoto, Japan) at 518 nm.

Ethanol (50% w/w) was added to the tubes containing nanoliposome (the ratio of nanoliposome to ethanol was 1:7). This mixture was transferred to an amicon filter (Millipore Amicon Ultra-15) and centrifuged (Nüve NF 1200R, Nüve, Ankara, Turkey) at 4000 rpm for 5 min. The resulting filtrate was used for identifying free essential oil content. For total essential oil (free and encapsulated oil) content, samples were combined with chloroform via continuous mixing for 15 min. The organic phase was removed and used for measuring the total essential oil content. The absorbance of the filtrate and organic phase was read against a blank at λmax = 270 nm using a UV–vis spectrophotometer (Model UV-1700, Shimadzu Corp., Kyoto, Japan). For the blank, nanoliposomes without essential oil were mixed with chloroform for 15 min and the absorbance of the organic phase was measured. The following Equations (1) and (2) were utilized to compute the encapsulation efficiency [36 (link),40 (link)]: $$Essential oil\left(\frac{mg}{mL}\right)=48.219\left({Abs}_{270}\right)-1.9634(R^2=0.99)$$
$$Encapsulation Efficieny\left(\%\right)=\frac{encapsulated essentail oil content}{total essential oil content}\times 100$$

UV/visible spectrophotometer (Model-UV-1700, Shimadzu, Japan) was employed for the spectral measurements. Lornoxicam was a generous gift sample from Life Care Formulations Pvt. Ltd., Pondicherry. Commercial tablets of lornoxicam (LORSAID 4, Abbott Healthcare Pvt. Ltd., Mumbai) were purchased from the local pharmacy. All other chemicals and solvents used were of analytical grade.

Cultured media from each bacterial strain was harvested in microtubes and the genomic DNA of each strain was extracted using the Genomic DNA extraction kit for bacteria (iNtRON Biotechnology, Seoul, Korea), according to the manufacturers instructions. Genomic DNA concentration was measured using a UV-spectrophotometer (Model UV-1700, Shimadzu, Tokyo, Japan) and genomic DNAs with spectrophotometric ratios of 1.8 to 2.0 (A₂₆₀/A₂₈₀) were used. Genomic DNAs were stored at −20 °C.

The EEP and its fractions were subjected to triplicate assessment at a concentration of 2.0 mg/mL. A total of 0.5 mL of 2 N Folin-Ciocalteu reagent and 1.0 mL of water were added per 0.5 mL of the propolis sample, and the tubes were agitated over two minutes. Next, 0.5 mL of 10 % sodium carbonate (Na₂CO₃) was added. Following incubation for two hours at room temperature with the tubes protected from light, absorbance was measured using a spectrophotometer (Model UV-1700, Shimadzu, Kyoto, Japan) at 750 nm. Methanol was used as blank [33 (link)].
Gallic acid (100 mg) was exactly weighted and transferred for volumetric flask (10 mL) and solubilised with methanol to obtain a stock solution (10.0 mg/mL). Gallic acid stock solution was diluted for concentrations of 1.0 mg/mL and solubilised with methanol to obtain work solution and aliquots of 0.150, 0.100, 0.050, 0.025, 0.010 and 0.005 mL were transferred for volumetric flask of 10 mL and solubilised with methanol to obtain concentration of 15.0, 10.0, 5.0, 2.5, 1.0 and 0.5 μg/mL and they were used for the calibration curve. The values of the total phenolic compounds were expressed as gallic acid equivalents (mg of gallic acid (GA)/g of sample) [33 (link)].