Comparison of Bioactive Secondary Metabolites and Cytotoxicity of Extracts from Inonotus obliquus Isolates from Different Host Species.

Inonotus obliquus, a wood-decaying mushroom, has been used as a health-promoting supplement and nutraceutical for centuries. It is a source of bioactive compounds accumulated in both the conks (pseudosclerotia/sclerotia) and the biomass obtained in vitro. This study aimed to qualitatively and quantitatively analyze the bioelements and selected metabolites produced in mycelial cultures obtained from different host species. The mycochemical potential of mycelial cultures isolated from pseudosclerotia grown in Betula pendula, Alnus glutinosa, and Carpinus betulus was compared. Parent cultures were obtained in two types of medium (malt extract agar substrates without and with birch wood). Experimental cultures were developed in 2 L bioreactors for 10 days. The content of bioelements was determined using FAAS and FAES methods. Organic compounds were estimated using the RP-HPLC-DAD method. The cytotoxicity of the extracts was evaluated in human keratinocytes HaCaT, human skin fibroblasts BJ, human liver cancer HepG2, human melanoma A375, and mouse melanoma B16-F10. The extracts showed the presence of bioelements: sodium, potassium, magnesium, calcium, zinc, manganese, iron, and copper; phenolic acids: p-hydroxybenzoic, caffeic, p-coumaric, and protocatechuic; sterols: lanosterol, ergosterol, ergosterol peroxide; triterpene compounds: betulin, betulinic acid, inotodiol; indole compounds: L-tryptophan, tryptamine, 5-methyltryptamine, melatonin. The content of bioactive substances in the biomass was dependent on both the origin of the host species of the fungus isolate and the type of culture medium. Based on the results of this study, mycelial cultures can be proposed as a potential source of bioactive compounds and are promising naturally derived cytotoxic agents.

Photodegradation of Bexarotene and Its Implication for Cytotoxicity.

A detailed understanding of the stability of an active pharmaceutical ingredient and a pharmaceutical dosage form is essential for the drug-development process and for safe and effective use of medicines. Photostability testing as an inherent part of stability studies provides valuable knowledge on degradation pathways and structures of products generated under UV irradiation. Photostability is particularly important for topically administered drugs, as they are more exposed to UV radiation. Bexarotene is a more recent third-generation retinoid approved by the U.S. Food and Drug Administration and the European Medicines Agency as a topically applied anticancer agent. The present study aimed to assess bexarotene photostability, including the presence of UV filters, which have been permitted to be used in cosmetic products in Europe and the USA. The bexarotene photostability testing was performed in ethanol solutions and in formulations applied on PMMA plates. The UPLC-MS/MS technique was used to determine the tested substance. The presence of photocatalysts such as TiO2 or ZnO, as well as the organic UV filters avobenzone, benzophenone-3, meradimate, and homosalate, could contribute to degradation of bexarotene under UV irradiation. Four photocatalytic degradation products of bexarotene were identified for the first time. The antiproliferative properties of the degradation products of bexarotene were assessed by MTT assay on a panel of human adherent cancer cells, and concentration-dependent growth inhibition was evidenced on all tested cell lines. The cytotoxicity of the formed products after 4 h of UV irradiation was significantly higher than that of the parent compound (p < 0.05). Furthermore non-cancerous murine fibroblasts exhibited marked concentration-dependent inhibition by bexarotene, while the degradation products elicited more pronounced antiproliferative action only at the highest applied concentration.

Changes in the Static Balance of Older Women Participating in Regular Nordic Walking Sessions and Nordic Walking Combined with Cognitive Training.

Regular Nordic walking (NW) improves physical fitness, including the ability to maintain balance, in older adults. However, little is known about whether complementing the exercise programme with cognitive training (CT) contributes to increased effects. The aim of the study was to determine and compare the effect of regular NW and NW combined with CT on the ability to maintain static balance in older adults. The study examined 61 women aged 64 to 93 years living in adult day care centres. Twenty people participated in a three-month programme combining NW and CT (group NW + CT), 20 people participated only in NW classes (group NW), and 21 people were a control group (group C). The Romberg balance test, Fullerton Functional Fitness Test, and Attention and Perceptivity Test were used. After the programme, an increase in the time of maintaining the balance (with eyes open on the left and right legs) was observed in groups NW + CT and NW, with no such changes found in group C. This increase was greater in group NW + CT. Increased agility and strength of the hand were predictors of improving the ability to maintain balance. Regular NW improved the ability to maintain balance with eyes open in female residents of adult day care centres.

Feasibility of the use of Lentinula edodes mycelium in terbinafine remediation.

A detailed understanding of the fate of xenobiotics introduced into the environment and the mechanisms involved in their biotransformation, biodegradation, and biosorption is essential to improve the efficiency of remediation techniques. Mycoremediation is a form of bioremediation technique that has become increasingly popular in recent years as fungi are known to produce various effective extracellular enzymes that have the potential to neutralize a wide variety of xenobiotics released into the environment. Hence, mycoremediation appears to be a promising technique for the removal of a wide array of toxins and pharmaceutical residues from a damaged environment and wastewater. This study primarily aimed to investigate whether white-rot fungus (Lentinula edodes) can be utilized for the bioremediation of common antifungal agent terbinafine, which is mainly available in the market as powder or cream. The cultures of L. edodes were cultivated in the medium containing terbinafine powder or terbinafine 1% cream, each at a final concentration of 0.1 mg mL-1. The addition of terbinafine in powder form have a negative effect on biomass growth (p < 0.05). The total amount of terbinafine in the dry weight of mycelium after culture was estimated to be 7.63 ± 0.45 mg and 12.52 ± 2.46 mg for powder and cream samples, respectively. In addition, there were no traces of terbinafine in any of the samples of medium used for culturing L. edodes after the experimental duration period. The biodegradation products of terbinafine were identified for the first time using UPLC/MS/MS. The biodegradation of terbinafine resulted in the loss of 1-naphthylmethanol, which occurred via oxidative deamination, N-demethylation, or tert-butyl group hydroxylation. The results of the study demonstrate that L. edodes mycelium can be effectively used for the remediation of terbinafine.

Changes in perceived quality of life and subjective age in older women participating in Nordic Walking classes and memory training.

BACKGROUND: The aim of the study was to determine the effect of regular Nordic walking (NW) and memory training on the quality of life and subjective age perception in older adults. Relationships between changes in quality of life and subjective age and changes in physical and perceptual fitness were also examined. METHODS: The study examined 61 women aged 64 to 93 years living in adult day care centers. Twenty people participated in a 3-month program combining Nordic walking and cognitive training (group NW+C), 20 people participated only in Nordic walking classes (group NW), and 21 people were a control group (group C). The Fullerton Functional Fitness Test, the Romberg balance test, WHOQOL-Bref Age questionnaire and the Attention and Perceptivity Test were used in the study. RESULTS: After three months of exercises, a decrease in subjective age and an improvement in perceived quality of life was observed in NW+C and NW groups, with no such changes found in group C. Positive correlations were also found for the index of decline in subjective age and quality of life with indices of physical fitness improvement. CONCLUSIONS: Regular physical and intellectual activity has a positive effect on perceived quality of life and subjective age of the residents of adult day care centers.

Mycoremediation of azole antifungal agents using in vitro cultures of Lentinula edodes.

Azole antifungal agents are widely used as active ingredients in antifungal pharmaceuticals and agricultural fungicides. An increase in the use of azole antifungals has resulted in an increase in the concentration of these compounds in wastewater and surface water, with potential implications for agriculture. In the present study, bifonazole (BIF) and clotrimazole (CTZ) were selected for investigation because of their widespread use in topical formulations and persistence in the environment. The mycoremediation capacity of BIF and CTZ by mycelia of Lentinula edodes in in vitro culture was evaluated. The main aim of this study was to identify the presumable biodegradation products of the investigated active pharmaceutical substances using the LC/MS/MS method. For this purpose, the media were enriched with the following active pharmaceutical ingredients selected for this study: BIF powder, CTZ powder, and BIF cream, each of them at the same concentration of 0.1 mg/mL. Subsequently, thin-layer chromatography coupled with densitometry was used to evaluate the content of BIF and CTZ in mycelium from in vitro cultures of L. edodes. The degradation process was found to affect primarily the imidazole moiety of both investigated compounds. In addition, the amounts of undegraded investigated compounds were found to be 4.98, 9.26, and 4.56 mg/g dry weight for BIF powder, CTZ powder, and BIF cream, respectively. Therefore, the findings of this study revealed that L. edodes could be considered for remediation of pollution caused by azole antifungal agents.

The Influence of Viscosity and Non-freezing Water Contents Bounded to Different Hydroxypropyl Celluloses (HPC) and Hydroxypropyl Methylcelluloses (HPMC) on Stability of Acetylsalicylic Acid.

The aim of the study was to examine the influence of non-freezing water (NFW) contents bound to hydroxypropyl methylcellulose (HPMC) or hydroxypropyl cellulose (HPC) binary mixtures using acetylsalicylic acid (ASA) as a model moisture-sensitive ingredient. Polysaccharides with significantly different physicochemical properties were mixed with acetylsalicylic acid at a ratio 1:1 (w/w). The measurements of NFW contents of hydrated samples were carried out using differential scanning calorimetry (DSC). In the method used, the dry mass normalized dependency of melting enthalpy (ΔH) and respective contents of water was found to be linear. NFW values were calculated after extrapolation ΔH to 0. For stability studies, HPC/ASA and HPMC/ASA mixtures were stored at 40°C and 75% RH for 5 weeks in the climatic chamber. The ASA hydrolysis was investigated using UV-Vis spectrophotometry. The amounts of NFW calculated for raw HPMC 3 cP and 100,000 cP were 0.49 and 0.42 g g-1, while for polymer and ASA mixtures, prepared from HPC type LF (126 cP) and MF (6300 cP) as well as from HPMC 3 cP and 100,000 cP were 0.23, 0.28 g g-1, 0.21 g g-1, and 0.33 g g-1 respectively. The measured NFW values were connected with appropriate concentrations of unhydrolyzed ASA.

The evaluation of effect of selected metal ions on the efficiency of passive and active transport of imipramine. / Ocena wplywu wybranych jonów metali na efektywnosc transportu biernego i aktywnego imipraminy.

OBJECTIVES: The aim of the study was to evaluate the effect of zinc as well as magnesium or copper ions on the efficacy of passive transport of imipramine hydrochloride in in vitro model. According to results from passive transport, the next aim of the studies was to check the efficiency of active transport of imipramine hydrochloride in the presence or absence of zinc ions. METHODS: The passive transport study was conducted in specially designed capsules, while CaCo-2 cell lines were used in active transport evaluation. Zinc, magnesium and copper content was determined by F-AAS method. The analysis of imipramine hydrochloride was performed using HPLC method. RESULTS: Mean concentrations of zinc, magnesium, and copper ions obtained in this experiment were as follows: 2.98, 1.34 and 3.52 mg/L, respectively. The presence of zinc ions increased the efficiency of active transport of imipramine hydrochloride by 39%. Furthermore, the transport of zinc ions in the presence of imipramine hydrochloride was 27% greater than that of the zinc-containing solutions without imipramine hydrochloride. The extending of the time of experiment from 30 to 60 minutes resulted in an increase in transport efficiency of more than 10% in both cases. CONCLUSIONS: The efficiency of passive and active transport of imipramine hydrochloride is influenced by the presence of Mg, Zn and Cu ions. The passive transport of imipramine hydrochloride after 90 minutes of experiment was the most effective in the presence of copper and zinc ions. Further studies conducted on the CaCo-2 cell line indicated a clear positive interaction of imipramine - zinc.

Effect of selected drugs on zinc accumulation in teeth of laboratory animals.

BACKGROUND: Zinc (Zn) is a micronutrient and essential element of life and its deficiency causes severe disorders of numerous body systems, such as immune, reproductive and central nervous system. Zinc supplementation affects wound healing and sexual development. The interactions between drugs administration and Zn level in tissues are not fully understood. The aim of the study was to demonstrate differences in Zn content in teeth of laboratory animals that have undergone pharmacological tests. METHODS: The teeth were extracted from laboratory animals after chronic administration of a non-steroidal anti-inflammatory drug (8-[4-[4-(4-chlorophenyl) piperazine-1-sulfonylphenyl]]-1-propylxanthine), a steroid anti-inflammatory drug (deoxycorticosterone) and an anti-cancer drug (oxaliplatin used acutely). The method of flame atomic absorption spectrometry was used to determine the Zn content in the teeth of the laboratory animals. RESULTS: Based on the studies conducted, the administration of the anti-inflammatory drug PSB-603 and deoxycorticosterone results in an increase in Zn accumulation in the teeth of laboratory animals, which may be indicative of the effect of anti-inflammatory drugs on the metabolism of this bioelement. Oxaliplatin has the opposite effect, after which the level of the measured bioelement in the teeth of mice depended on the administered dose. This level was on average 21.0-28.1% lower than the Zn level in the teeth of the control group. Anti-cancer drugs may interfere with Zn accumulation in the teeth and cause the removal of this metal from bone tissue. CONCLUSION: It can be assumed that the Zn content in teeth can be markedly affected by the drugs that were administrated to animals.

The impact of ZnO and TiO2 on the stability of clotrimazole under UVA irradiation: Identification of photocatalytic degradation products and in vitro cytotoxicity assessment.

In order to ensure the safe and effective use of pharmaceutical products especially for topical administration photostability testing is necessary. The current paper presents an in-depth analysis of the stability of one of the most common antifungal agents, namely clotrimazole. Clotrimazole has proven to be stable under UVA irradiation in applied experimental conditions, but the presence of catalysts such as ZnO and TiO2 has contributed significantly to the degradation of this compound. The findings indicate that its photocatalytic degradation reactions followed the pseudo first-order kinetics with rate constant depending on the pH and the used solvent. Using LC-MS/MS, 14 presumable degradation products of clotrimazole were identified and the plausible transformation pathways were proposed. The in vitro cytotoxicity risk evaluation based on photostability of clotrimazole was also performed using the Human skin fibroblast cell line (BJ) ATCC™ CRL-2522. There was no statistically significant difference between cells viability in all analyzed combinations of clotrimazole, TiO2/ZnO, and UVA irradiation (p<0.05).

Nicotine affects hydrogen sulfide concentrations in mouse kidney and heart but not in brain and liver tissues.

Nicotine, a potent parasympathomimetic alkaloid with stimulant effects, is contributing to addictive properties of tobacco smoking and is though used in the smoking cessation therapy. Hydrogen sulfide (H2S) is involved in physiology and pathophysiology of various systems in mammals. The interactions between nicotine and H2S are not fully recognized. The aim of the study is to assess the influence of nicotine on the H2S tissue concentrations in different mouse organs. Adult CBA male mice were administered intraperitoneally 1.5 mg/kg b.w. per day of nicotine (group D1, n = 10) or 3 mg/ kg b.w. per day of nicotine (group D2, n = 10). The control group (n = 10) received physiological saline. The measurements of the free and acid-labile H2S tissue concentrations were performed with the Siegel spectrophotometric modi ed method. ere was a significant increase in H2S concentrations in both nicotine doses groups in the kidney (D1 by 54.2%, D2 by 40.0%). In the heart the higher nicotine dose caused a marked decrease in H2S tissue level (by 65.4%), while the lower dose did not affect H2S content. Nicotine administration had no effect on H2S concentrations in the brain and liver. In conclusion, nicotine affects H2S tissue concentrations in kidney and heart but not in the liver and brain tissues.

Remediation capacity of Cd and Pb ions by mycelia of Imleria badia, Laetiporus sulphureus, and Agaricus bisporus in vitro cultures.

The goal of this study was to evaluate cadmium and lead accumulation ability of in vitro cultures biomass containing selected edible mushroom species derived from the environment (Laetiporus sulphureus, Imleria badia) and those of commercial origin (Agaricus bisporus). Atomic absorption spectrometry was used to evaluate the content of Cd(II) and Pb(II) on the medium supplemented with Cd(II) or Pb(II), each of them at the same concentration of 5·10-5 M. The highest concentration of Cd(II) ions was determined in the biomass from L. sulphureus in vitro cultures, while the highest concentration of Pb(II) ions was found in the biomass from A. bisporus in vitro cultures. The greatest Cd(II) and Pb(II) accumulation ability in mycelium per dry weight was shown for L. sulphureus. Among the test species, biomass of A. bisporus showed the lowest ability for the bioaccumulation of Cd(II); however, comparable ability for the remediation of Pb(II) was provided by the biomasses from A. bisporus and I. badia in vitro cultures. The results confirm the possibility of using these mushroom species for remediation and indicate the relationship between bioaccumulation of heavy metals and the test species.

Zinc transporters protein level in postmortem brain of depressed subjects and suicide victims.

BACKGROUND: Major depressive disorder (MDD) is a serious psychiatric illness, associated with an increasing rate of suicide. The pathogenesis of depression may be associated with the disruption of zinc (Zn) homeostasis. In the brain, several proteins that regulate Zn homeostasis are present, including Zn transporters (ZnTs) which remove Zn from the cytosol. The present study was designed to investigate whether depression and suicide are associated with alterations in the expression of the ZnTs protein. METHODS: Protein levels of ZnT1, ZnT3, ZnT4, ZnT5 and ZnT6 were measured in postmortem brain tissue from two different cohorts. Cohort A contained 10 subjects diagnosed with MDD (7 were suicide victims) and 10 psychiatrically-normal control subjects and cohort B contained 11 non-diagnosed suicide victims and 8 sudden-death control subjects. Moreover, in cohort A we measured protein level of NMDA (GluN2A subunit), AMPA (GluA1 subunit) and 5-HT1A receptors and PSD-95. Proteins were measured in the prefrontal cortex (PFC) using Western blotting. In addition, Zn concentration was measured using a voltammetric method. RESULTS: There was a significant increase in protein levels of ZnT1, ZnT4, ZnT5 in the PFC in MDD, relative to control subjects, while ZnT3 protein level was decreased in MDD. There was no significant difference in the Zn concentration in the PFC between control and MDD subjects. Similarly, in the PFC of suicide victims (non-diagnosed), an increase in protein levels of ZnT1, ZnT4, ZnT5 and ZnT6 was observed. Conversely, protein levels of ZnT3 were decreased in both suicide victims and subjects with MDD, in comparison with control subjects. There was also a significant decrease in the protein level of GluA1, GluN2A, PSD-95 and 5-HT1A in MDD. CONCLUSIONS: Our studies suggest that alterations in Zn transport proteins are associated with the pathophysiology of MDD and suicide.

Cocaine exposure alters H2S tissue concentrations in peripheral mouse organs.

BACKGROUND: Hydrogen sulfide (H2S) is well-known as a physiological mediator in the mammalian brain and peripheral tissues. Among several factors that change the concentration of H2S, oxidative stress and generation of reactive oxygen species, which accompany neurochemical actions of drugs of abuse, are of recent interest. OBJECTIVE: Limited data on the connection of cocaine and H2S levels prompted us to investigate the effect of this psychostimulant on the H2S concentration in the mouse brain and peripheral organs. METHODS: Male BALB/C mice were given several cocaine dosage and treatment regimens, and the free and acid-labile H2S tissue concentrations were determined with a modified spectrophotometric method of Siegel. RESULTS: We demonstrated the dose- and treatment-dependent decreases in the H2S level in the heart (83% of control level), and in the liver and kidney (17-34% of control levels) homogenates, but no changes were seen in the mouse brain. The strongest effect occurred after repeated administration of cocaine (20mg/kg) in all peripheral tissues. CONCLUSION: A reduction in the peripheral tissue H2S level in the heart, liver and kidney homogenates after repeated injections of cocaine may be the result of a strong toxic effect of the drug.

Determination of neomycin in the form of neomycin derivative with dabsyl chloride by thin layer chromatography and densitometry.

A thin layer chromatographic-densitometric method has been developed for identification and quantitative determination of neomycin derivative with dabsyl chloride. The analysis of antibiotic was achieved on the silica gel TLC plates with fluorescent indicator with n-butanol--2-butanone--25% ammonia--water (10 : 6 : 2 : 2, v/v/v/v) as the mobile phase. The densitometric measurements were made at 460 nm. Under these conditions good separation of chosen aminoglycoside antibiotic from reagent used to make a complex was obtained. The method is characterized by high sensitivity, LOD from 0.1953 µg per band and LOQ from 0.5918 µg per band, wide linearity range from 0.5918 to 2.1960 µg per band for neomycin. The precision of the method was good; RSD varied from 1.17 to 2.05%. Satisfactory results of validation of the method were also confirmed by determination of selected antibiotic in pharmaceutical commercial preparation. The results obtained by TLC-densitometric method were compared with those obtained by spectrophotometric method.

Metformin raises hydrogen sulfide tissue concentrations in various mouse organs.

BACKGROUND: The epidemic of diabetes mellitus type 2 forces to intensive work on the disease medication. Metformin, the most widely prescribed insulin sensitizer, exerts pleiotropic actions on different tissues by not fully recognized mechanisms. Hydrogen sulfide (H2S) is involved in physiology and pathophysiology of various systems in mammals and is perceived as a potential agent in the treatment of different disorders. The interaction between biguanides and H2S is unknown. The aim of the study is to assess the influence of metformin on the H2S tissue concentrations in different mouse organs. METHODS: Adult SJL female mice were administered intraperitoneally 100 mg/kg b.w. per day of metformin (group D1, n = 6) or 200 mg/kg b.w. per day of metformin (group D2, n = 7). The control group (n = 6) received physiological saline. The measurements of the free and acid-labile H2S tissue concentrations were performed with Siegel spectrophotometric modified method. RESULTS: There was a significant progressive increase in the H2S concentration along with the rising metformin doses as compared to the control group in the brain (D1 by 103.6%, D2 by 113.5%), in the heart (D1 by 11.7%, D2 by 27.5%) and in the kidney (D1 by 7.1%, D2 by 9.6%). In the liver, massive H2S accumulation was observed in the group D1 (increase by 420.4%), while in the D2 group only slight H2S level enhancement was noted (by 12.5%). CONCLUSION: Our experiment has shown that metformin administration is followed by H2S tissue concentrations increase in mouse brain, heart, kidney and liver.

Stevia, cyclamate and saccharin - natural and artificial sweeteners - exert no effect on sulfane levels in tissues.

The interactions among natural and artificial sweeteners and endogenous sulfur metabolism have never been investigated. CBA strain mice were administered orally stevia, cyclamate or saccharin in doses of 5 mg/kg of body weight in water solutions each. The measurements of the free and acid-labile sulfane (H2S) tissue concentrations in brain, heart, liver and kidney were performed with Siegel spectrophotometric modified method. No differences in comparisons between hydrogen sulfide concentrations in the control group and each sweetener group within every tissue type were noted. In conclusion, stevia, cyclamate and saccharine do not change the endogenous sulfur metabolism to the extent of causing sulfane tissue levels alterations.

Application of chemometrically processed thermogravimetric data for identification of baclofen-excipient interactions.

Studies are constantly being conducted on the elaboration of efficient methods to confirm the compatibility of active pharmaceutical ingredients (APIs) and excipients, since medicinal products, apart from their APIs, also contain numerous excipients that not only have important functions in pharmaceutical preparations but can also initiate or participate in interactions with drug substances, which eventually lead to a decline in drug quality. With this in mind, research was undertaken to evaluate two of the most often applied pattern recognition methods, hierarchical cluster analysis (HCA) and principal component analysis (PCA), as supporting techniques in the identification of potential physicochemical interactions that may occur during the preformulation of solid dosage forms. The investigation performed with the use of baclofen and selected excipients has shown that with thermogravimetric analysis, HCA and PCA fulfill their role as supporting techniques in the interpretation of the data obtained. Based on these methods, it is possible to detect incompatibilities between baclofen and excipients, and the data obtained concur strongly with the results of differential scanning calorimetry and IR spectrometry analyses.

Vitamin D3 (cholecalciferol) boosts hydrogen sulfide tissue concentrations in heart and other mouse organs.

Vitamin D3 is a crucial co-regulator of bone growth and remodeling, neuromuscular function, inflammation, proliferation, differentiation and apoptosis of cells. Intensive research on endogenous sulfur metabolism has revealed that hydrogen sulfide (H2S) is an important modulator of various physiological processes in mammals. Noteworthy, these compounds are perceived as potential agents in the treatment of numerous disorders, including cardiovascular diseases and different types of cancer. The interaction between vitamin D3 and H2S is unknown. The aim of the study is to assess the influence of cholecalciferol (vitamin D3, calcitriol) on H2S tissue concentrations in mouse brain, heart and kidney. Twenty four SJL mice were given intraperitoneal injections of cholecalciferol at 10000 IU/kg body weight (b.w.) per day (group A, n = 8) or 40000 IU/kg b.w. per day (group B, n = 8). The control group (n = 8) received physiological saline. Free H2S tissue concentrations were measured via the SIEGEL spectrophotometric modified method. There was a significant progressive increase in the H2S concentration along with the rising cholecalciferol doses as compared to the control group in the heart (by 29.6% and by 74.1%, respectively). Higher vitamin D3 dose caused H2S accumulation in the brain (by 10.9%) and in the kidney (by 10.1%). Our study has proven that cholecalciferol affects H2S tissue concentration in different mouse organs.

Spectrophotometric determination of bacitracin in bulk drug as dabsyl derivative in a range of visible light.

A fast spectrophotometric method has been developed for bacitracin identification and determination after condensation reaction with dabsyl chloride. In addition, determination of dye stability of sulfonamide derivative and identification of the molar ratio of reagents was done at various time-points. The developed method has a good linearity with very broad spectrum, correlation coefficient of r = 0.9972, good precision (RSD = 1.54 +/- 0.11%), and recovery at three different levels of concentration was found between 98.33% and 103.47%. Usefulness of the method was demonstrated by positive results obtained during determination of bacitracin concentration in bulk drug.