Xanthohumol, a prenylated chalcone in the flavonoid group, naturally occurs in many plants and exhibits antioxidant, anticancer, anti-inflammatory, antibacterial, and antiviral effects. The growing interest in xanthohumol due to its potential therapeutic properties has led to the increase in the pool of products available on the market. The novelty of this study is the proposal of a rapid and cost-effective procedure useful for performing quality control on products containing xanthohumol in the form of dietary supplements and cosmetics as well as testing their stability. For this purpose, the thin-layer chromatography method with densitometric detection was used, which was validated in accordance with ICH (International Conference on Harmonization) guidelines. The mobile phase was toluene, 1,4-dioxane, and glacial acetic acid (37:10:1.5 v/v/v), and TLC silica gel 60 F254 plates were used as the stationary phase. The validation process assessed linearity, with a correlation coefficient (r) of 0.9987. The calculated LOD (limit of detection) and LOQ (limit of quantification) values were 3.82 and 11.57 ng/spot, respectively. Accuracy was evaluated by determining percentage recovery at three concentration levels (80, 100, and 120%), with an average recovery of 100% and RSD below 1%, confirming good accuracy. Precision was indicated by an RSD of less than 2.20%. The average content of xanthohumol in dietary supplements ranged from about 8 to 29% of the content declared by the manufacturers. The stability tests showed that XN decomposes most slowly in water (t0.5 = 10.86 h) compared with acidic (t0.5 = 10.80 h) and alkaline solutions (t0.5 = 7.39 h), as well as in the presence of an oxidizing agent (t0.5 = 18.38 h), at all tested temperatures, which is confirmed by the calculated kinetic parameters. In the tests of antioxidant capacity, xanthohumol shows significantly higher radical scavenging capacity than vitamin C in the entire range of analyzed concentrations (0.03–2.40 mmol/L).

Abiotic elicitation, a well-known strategy in mushroom biotechnology, promotes increased accumulation of secondary metabolites in mycelial cultures. The study aimed the effects of methyl jasmonate (MeJA) on the production of triterpenes in submerged cultures of Ganoderma applanatum. Further, the study evaluated the cytotoxic activity of the extract corresponding to the optimal elicitation variant in selected human cancer cell lines as well as the selectivity against normal cells. MeJA was added on days 1, 4, 6, and 8 in the 10-day growth cycle at concentrations of 10, 50, 100, 150, and 200 µM MeJA. The HPLC-DAD was used to analyze the triterpenes. The cytotoxic activity was tested using the MTTFc assay in grouped panels of skin, prostate, and gastrointestinal cancer cells. The results of the quantitative analyses confirmed the stimulating effect of MeJA on the production of ganoderic acid A and ganoderic acid C. The greatest increase in total triterpenes was found on day 6 of the culture cycle compared to the control group—with the concentration of MeJA—150 µM. Compared to the control samples, mycelial culture extract after the most productive elicitation variant showed significant cytotoxic activity against prostate cancer cells and moderate effects on melanoma cells. Ganoderma applanatum mycelial cultures can be proposed as a model to study the dynamics of the accumulation of compounds with therapeutic values through abiotic elicitation.

The study has proved the stimulating effects of different strategies of treatments with elicitors on the production of glucosinolates (GSLs), flavonoids, polyphenols, saccharides, and photosynthetic pigments in watercress ( Nasturtium officinale ) microshoot cultures. The study also assessed antioxidant and anti-melanin activities. The following elicitors were tested: ethephon (ETH), methyl jasmonate (MeJA), sodium salicylate (NaSA), and yeast extract (YeE) and were added on day 10 of the growth period. Cultures not treated with the elicitor were used as control. The total GSL content estimations and UHPLC-DAD-MS/MS analyses showed that elicitation influenced the qualitative and quantitative profiles of GSLs. MeJA stimulated the production of gluconasturtiin (68.34 mg/100 g dried weight (DW)) and glucobrassicin (65.95 mg/100 g DW). The elicitation also increased flavonoid accumulation (max. 1131.33 mg/100 g DW, for 100 μM NaSA, collection after 24 h). The elicitors did not boost the total polyphenol content. NaSA at 100 μM increased the production of total chlorophyll a and b (5.7 times after 24 h of treatment), and 50 μM NaSA caused a 6.5 times higher production of carotenoids after 8 days of treatment. The antioxidant potential (assessed with the CUPRAC FRAP and DPPH assays) increased most after 24 h of treatment with 100 μM MeJA. The assessment of anti-melanin activities showed that the microshoot extracts were able to cause inhibition of tyrosinase (max. 27.84% for 1250 µg/mL). Key points • Elicitation stimulated of the metabolite production in N. officinale microshoots. • High production of pro-health glucosinolates and polyphenols was obtained. • N. officinale microshoots have got tyrosinase inhibition potential. • The antioxidant potential of N. officinale microshoots was evaluated. Graphical abstract

This study analyzed the content of substances with cosmetologic properties in the extracts obtained from the mycelial cultures of Ganoderma applanatum, Laetiporus sulphureus, and Trametes versicolor. The effect of these extracts on the inhibition of tyrosinase and hyaluronidase was determined, and their values of sun protection factor (SPF) were calculated. The total amount of phenolic acids in the extracts ranged from 2.69 (G. applanatum) to 10.30 mg/100 g dry weight (T. versicolor). The total amount of sterols was estimated at 48.40 (T. versicolor) to 201.04 mg/100 g dry weight (L. sulphureus), and that of indoles at 2.90 (G. applanatum) to 16.74 mg/100 dry weight (L. sulphureus). Kojic acid was determined in the extracts of L. sulphureus and G. applanatum. It was observed that L. sulphureus extract caused dose-dependent inhibition of hyaluronidase, while all the extracts inhibited tyrosinase. The extract of G. applanatum exhibited an SPF value of ~ 9. The results showed that the mycelial cultures of the studied species may be used as an alternative source of substances used in cosmetology.

The TLC method with densitometric detection was used to identify and determine the content of candesartan (CAN), hydrochlorothiazide (HCT), and rosuvastatin (ROS) as active ingredients of a potential FDC (fixed-dose combination) preparations. TLC F-254 plates were used as a stationary phase and a mobile phase was composed of: hexane - ethyl acetate - methanol - water - 99.5% acetic acid (8.4 : 8 : 3 : 0.4 : 0.2 V/V). The obtained chromatograms are characterized by a good separation of the tested substances, enabling the assessment of results in both qualitative and quantitative aspects. The process of method validation has shown that the method is specific for the analyte and is characterized by high sensitivity. The linearity was determined in a wide range. from 0.048 to 1.824 mg/spot for CAN, from 0.058 to 1.102 mg/spot for Her and from 0.032 to 1.216 mg/spot for ROS and determination coefficient (R-2) was between 0.9985-0.9990 depending on the substance being determined. The recovery ranged from 96.8% to 101.12%. The precision of the method was satisfactory, RSD values were in the range from 0.43% to 2.12%.

Problems in polytherapy of hypertension combined with hyperlipidemia and the need of application of several pharmaceutical preparations have been widely explored by patients, physicians, and the pharmaceutical industry through testing and introduction of a fixed-dose-combination products (FDC). The paper presents different analytical methods of qualitative and quantitative analysis or stability testing of FDC preparations and laboratory prepared mixtures of composition consistent with the FDC products collected on the basis of publications from the last decade. It can significantly facilitate the study of the methods and conditions for the determination of active substances in polypills which contain at least three APIs, especially in cases involving this type of preparations used or tested for their application in polytherapy of hypertension.

A new chromatographic-densitometric method has been developed for the qualitative and quantitative determination of the active ingredients in a simulated mixture corresponding to the PolyIran polypill, composed of acetylsalicylic acid, hydrochlorothiazide (HCT), enalapril (ENA), and atorvastatin (ATR), whose efficacy in the treatment and prevention of cardiovascular disease has been documented in clinical trials. Chromatographic separation was performed using TLC silica gel 60 plates with fluorescent indicator F254 as the stationary phase and a mixture of n-hexane-ethyl acetate-methanol-water-acetic acid (8.4 + 8 + 3 + 0.4 + 0.2, v/v/v/v/v) as the mobile phase. Densitometric measurements were carried out at λ = 210 nm when determining ENA and at λ = 265 nm in the case of the other drugs. Peaks of examined substances were well separated in the recorded chromatograms, enabling the evaluation of the results in terms of both qualitative and quantitative analysis. The method was specific for the analyzed components and was characterized by high sensitivity. The LOD was between 0.043 and 0.331 μg/spot, and LOQ was between 0.100 and 0.942 μg/spot. Recovery was in the range of 97.02-101.34%. The linearity range was broad and ranged from 0.600 to 6.000 μg/spot for acetylsalicylic acid, from 0.058 to 1.102 μg/spot for HCT, from 0.505 to 6.560 μg/spot for ENA, and from 0.100 to 1.000 μg/spot for ATR. The method was characterized by good precision, with RSD values that ranged from 0.10 to 2.26%.

Applicability of derivative spectrophotometry for the determination of valsartan in the presence of a substance from the group of statins was checked. The obtained results indicate that the proposed method may be effective by using appropriate derivatives: for valsartan and fluvastatin - D1, D2 and D3, for valsartan and pravastatin - D1 and D3, for valsartan and atorvastatin - D2 and D3. The method was characterized by high sensitivity and accuracy. Linearity was maintained in the following ranges: 9.28-32.48 mg mL-1 for valsartan, 8.16-28.56 mg mL-1 f or fluvastatin, 14.40-39.90 mg mL-1 for atorvastatin and 9.60-48.00 mg mL-1 for pravastatin. Determination coefficients were in the range of 0.989-0.999 depending on the analyte and the order of derivative. The precision of the method was high with RSD from 0.1 to 2.5 % and recovery of individual components was within the range of 100 ± 5 %. The developed method was successfully applied to the determination of valsartan combined with fluvastatin, atorvastatin and pravastatin in laboratory prepared mixtures and in pharmaceutical preparations.

The usefulness of derivative spectrophotometry for the determination of labetalol, sotalol and oxprenolol in binary mixtures and in human spiked serum was checked. To this aim a spectrophotometric analysis of samples in the UV range was carried out and the obtained results revealed that derivative spectropho- tometry allows for the fast, accurate and precise determination of the tested substances in spite of their clear interference in the zero-order spectra. For quantitative determinations "zero-crossing" technique was used to establish wavelengths for zeros of specified component. In a mixture of labetalol and oxprenolol the following wavelengths were established: D1 λ = 245.32 nm and 266.03 nm, D2 λ = 243.30 nm and 301.09 nm. respectively. D3 derivative did not show zeros suitable for quantitative analysis. For the analysis of labetalol and sotalol mixture, D3 derivative spectrophotometry was used at the following wavelengths: = 246.03 nm and λ = 249.91 rum, respectively. In this case, the curves of Dl and D2 derivatives showed no zeros that can be used in quantitative analysis. To determine the concentration of the components in a mixture containing oxprenolol and sotalol the following wavelengths were selected: for oxprenolol DI λ = 245.32 nm, D2 λ = 240.18 run, D3 λ = 232.05 nm and for sotalol Dl λ = 230.56 nm, D2 Xλ= 232.65 nm and D3 X = 238.84 tm, respectively. The developed spectrophotometric method was characterized by high sensitivity and accuracy, LOD determined for sotalol was in the range of 0.21-1.88 μg/mL, for labetalol 1.00-3.43 μg/mL and for oxprenolol 0.16-2.06 μg/mL; LOQ determined for sotalol was in the range of 0.65-5.70 μg/mL, for labetalol 3.11-10.39 μg/mL and for oxprenolol 0.47-6.23 μg/mL, depending on the composition of the tested mixture and the order of the deriv- ative. The recovery of the individual components was within the range of 100 ± 5%. The linearity range was wide and estimated for sotalol in the range of 11.00-38.50 μg/mL, for labetalol 12.80-44.80 μg/mL and for oxprenolol 12.60-44.10 μg/mL with correlation coefficients in the range of 0.9977-0.9999.

We review analytical methods used to determine new substances with hypotensive activity from two pharmacological groups: renin inhibitors and endothelin receptor antagonists.

Fast, accurate and precise method for the determination of zofenopril and fluvastatin was developed using spectrophotometry of the first (D1), second (D2), and third (D3) order derivatives in two-component mixtures and in pharmaceutical preparations. It was shown, that the developed method allows for the determination of the tested components in a direct manner, despite the apparent interference of the absorption spectra in the UV range. For quantitative determinations, "zero-crossing" method was chosen, appropriate wavelengths for zofenopril were: D1 λ=270.85 nm, D2 λ=286.38 nm, D3 λ=253.90 nm. Fluvastatin was determined at wavelengths: D1 λ=339.03 nm, D2 λ=252.57 nm, D3 λ=258.50 nm, respectively. The method was characterized by high sensitivity and accuracy, for zofenopril LOD was in the range of 0.19-0.87 μg mL(-1), for fluvastatin 0.51-1.18 μg mL(-1), depending on the class of derivative, and for zofenopril and fluvastatin LOQ was 0.57-2.64 μg mL(-1) and 1.56-3.57 μg mL(-1), respectively. The recovery of individual components was within the range of 100±5%. For zofenopril, the linearity range was estimated between 7.65 μg mL(-1) and 22.94 μg mL(-1), and for fluvastatin between 5.60 μg mL(-1) and 28.00 μg mL(-1).

Two methods, spectrophotometric and chromatographic-densitometric ones, were developed for determination of losartan potassium, quinapril hydrochloride and hydrochlorothiazide in pharmaceutical preparations. Spectrophotometric method involved derivative spectrophotometry and zero order spectrophotometry. The measurements were carried out at lambda = 224.0 nm for quinapril, lambda = 261.0 nm for hydrochlorothiazide and lambda = 270.0 nm for losartan when the derivative spectrophotometry was applied and lambda = 317.0 nm when zero order spectrophotometry was applied for the determination of hydrochlorothiazide. In chromatographic-densitometric studies high performance thin layer chromatography (HPTLC) plates were used as stationary phase and a mixture of solvents n-butanol : acetic acid : water (15 : 5 : 1, v/v/v) as mobile phase. Under the established conditions good resolution of examined constituents was obtained. Retardation factor for quinapril hydrochloride was R(f) - 0.70, for losartan potassium R(f) - 0.85 and for hydrochlorothiazide R(f) - 0.78. The developed methods are characterized by high sensitivity and accuracy. For quantitative analysis, densitometric measurements were carried out at lambda = 218.0 nm for quinapril, lambda = 275.0 nm for hydrochlorothiazide and = 232.0 nm for losartan.

This is a review of analytical methods, such as spectrophotometry, derivative spectrophotometry and various chromatographic (gas chromatography-GC, high-performance liquid chromatography-HPLC, thin-layer chromatography-TLC, high-performance thin-layer chromatography-HPTLC, liquid chromatography-tandem mass spectrometry-LC-MS, microchip electrophoresis-MCE, capillary electrophoresis-CE) and electroanalytical methods (differential pulse polarography-DPP, cathodic stripping voltammetry-CSV, anodic stripping voltammetry-ASV, differential pulse voltammetry-DPV, cyclic voltammetry-CV, stripping voltammetry-SV, square wave voltammetry-SWV, square wave polarography-SWP) that are used in the analysis of hypotensive complex agents. This review is based on representative publications that were published between 1995 and 2009.

First (DI) and second (D2) order derivative spectrophotometric method with an application of base line to peak technique was used for determination of active pharmaceutical ingredients (API) at two wavelengths: fluphenazine (D1 at lambda = 251 nm and lambda = 265 nm, D2 at lambda = 246 nm and lambda = 269 nm), pernazine (D1 at lambda = 246 nm and lambda = 258 nm, D2 at lambda = 254 nm and lambda = 262 nm), haloperidol (DI at = 235 nm and lambda = 253 nm, D2 at lambda = 230 nm and lambda = 246 nm), and promazine (D1 at lambda = 246 nm and lambda = 251 nm, D2 at lambda = 255 nm and lambda = 262 nm). Linear dependence of derivative values on analyte concentration is maintained in a range 3.12 microg x mL(-1) - 44.80 microg x mL(-1). Detection and determination limits are in the range 0.51 - 3.23 microg x mL(-1) and 1.27 microg x mL(-1) - 9.80 microg x mL(-1), respectively. Determination results of drug constituents are very accurate. Recovery percentage is in a range 95.50% - 103.60%.

Pharmaceutical preparations containing sodium fluoride as an active substance have been examined. To do it, a procedure developed previously that uses the inhibition of redox reaction in the system under investigation was employed. For determination purposes, visible range spectrophotometry and redoxometric titration enabling indirect quantitative determination of fluoride ions in preparations under examination have been applied. The satisfactory results confirmed by statistical parameters were obtained.

A quick and accurate method for determining triamterene and hydrochlorothiazide in complex drugs of diuretic activity by using first-derivative (D1) and second-derivative (D2) spectrophotometry was developed. The zero-crossing technique was employed in measurements, using D1 at lambda = 240.9 nm and D2 at lambda= 278.2 nm for determining triamterene and D1 at lambda = 255.7 nm and D2 at lambda = 283.2 nm for hydrochlorothiazide. The linear relationship between the values of derivatives and analyte concentrations are maintained for concentrations from 2.40 microg x mL(-1) to 12.00 microg x mL(-1) for triamterene and from 1.25 microg x mL(-1) to 6.25 microg x mL(-1) for hydrochlorothiazide. LOD for triamterene was 0.90 microg x mL(-1) or 1.02 microg x mL(-1), while LOQ was 2.73 microg x mL(-1) or 3.08 microg x mL(-1). The corresponding values for hydrochlorothiazide were: LOD 0.25 microg x mL(-1) or 0.17 microg x mL(-1) and LOQ 0.77 microg x mL(-1) or 0.51 microg x mL(-1) depending on the derivative used. The determination results of drug constituents are of high accuracy, percentage recovery ranging from 97.17% to 99.74% for triamterene and from 102.44% to 102.64% for hydrochlorothiazide, and good precision. The computed values of RSD are smaller than 2.73% for triamterene and below 1.63% for hydrochlorothiazide. Selectivity and sensitivity of the developed method are satisfactory.

A UV spectrophotometric method was developed for simultaneous determination of ions: Pb(II), Fe(III) and Bi(III) in complexes with DACT. Zero-order and derivative spectra were used for the determinations. Under the established experimental conditions the described method furnished reliable results with low limit of detection (from 0.09 microg x mL(-1) to 1.75 microg x mL(-1)), high recovery (from 96.08% to 97.81%) and broad range of linearity for the analyzed ions. Good precision of the method was confirmed in experiments on model solutions containing mixtures of ions studied at different concentrations and in statistical analysis of the data obtained.

Athin layer chromatographic method with densitometric UV detection at λ = 285 nm has been developed for quantification of embelin in Lysimachia punctata. TLC analysis was performed on aluminumbacked silica gel 60 F254 plates with n-hexane—ethyl acetate, 7 + 3 (v/v), as mobile phase. Under these experimental conditions the method was highly sensitive (the limit of detection was 12.5 ng) and recovery was satisfactory (from 89.45% to 92.28%). Good results obtained during validation of the method were confirmed in quantification of embelin, because high precision and accuracy were achieved.