Mohammad Charehsaz

Effect of in vitro gastrointestinal digestion on the bioavailability of phenolic components and the antioxidant potentials of some Turkish fruit wines

This study was designed to evaluate the effects of in vitro gastrointestinal simulation method on the antioxidant potentials and phenolic profile of some Turkish fruit wines and to compare the results with a Turkish red wine prepared from native grape varieties (Papazkarası). For this purpose, blueberry, black mulberry and cherry wines were studied since they are widely consumed in Turkey. Papazkarası wine was chosen due to the lack of studies regarding this type of wine. Antioxidant potentials of samples were measured with four different methods: DPPH radical-scavenging activity, H2O2-scavenging activity, cupric reducing capacity and total antioxidant capacity assays. The phenolic profiles of samples were evaluated by the determination of total phenolic content and HPLC-DAD analysis of seven different molecules. The results of this study provided information not only the effect of gastrointestinal digestion on parameters mentioned above, but also the bioaccessibility about the phenolic compounds found in these four different wine samples.

Nanoparticles Toxicity and Their Routes of Exposures

Due to their small size, nanotechnology based materials have unique characteristics such as magnetic, optical, thermal, mechanical, electrical, electron configuration density when compared with macromolecules. Nanomaterials are generally at the 1–100 nm scale and have a vast range of applications such as in medicine, electronics and energy production. Cosmetics, sunscreens, coatings, batteries, fuel additives, paints, pigments, tires and cement are the examples of consumer products that based on nanotechnology. Nanomaterials may also used for special medical purposes such as to produce novel drug delivery systems, to enhance the performance of medical devices, or to produce diagnostic-imaging materials [1].

Energy Drink Induced Lipid Peroxidation and Oxidative Damage in Rat Liver and Brain When Used Alone or Combined with Alcohol

Energy drinks (ED) are containing large doses of metabolic stimulants and its use with ethanol has increased dramatically among young adults. In this study, we examined the effects of ED exposure either alone or in combination with ethanol on oxidative stress parameters including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and lipid peroxidation parameter malondialdehyde (MDA) in rat. Some histopathological findings were also evaluated. ED exposure led to a dose-dependent increase in liver MDA compared to the control indicating oxidative damage. Histopathological findings also revealed that ED alone may generate liver damage. Ethanol exposure increased MDA level and SOD, CAT, and GSH-Px activity in both the brain and the liver. The combination of ethanol and ED produced greater damage which is considered by further increases in SOD and GSH-Px activity in the brain. Similar results for MDA were observed in both the liver and brain as well. Our findings suggest that ED consumption alone or combination with ethanol may represent a significant public health concern.

Effects of globularifolin on cell survival, nuclear factor-κB activity, neopterin production, tryptophan breakdown and free radicals in vitro.

The potential effects of globularifolin, an acylated iridoid glucoside, on cell survival, inflammation markers and free radicals scavenging were investigated. Viability assay on human myelomomonocytic cell line THP-1 and human peripheral blood mononuclear cells (PBMC) using the Cell-Titer Blue assay proved that globularifolin had no toxic effect at the tested concentrations. Conversely, it is proportional to the dose globularifolin increased growth of THP-1 cells (p <0.01). On human PBMC, globularifolin at 6.25 and 12.5 μM concentrations showed a stimulatory effect, while at 12.5-200 μM it suppressed response of PBMC to stimulation with phytohemagglutinin (PHA). Globularifolin (50-200 μM) enhanced neopterin formation dose-dependently, whereas tryptophan breakdown was not influenced. At 50-200 μM in unstimulated PBMC in THP-1 cells, globularifolin induced a significant expression of nuclear factor-κB (NF-κB) as was quantified by Quanti-Blue assay. By contrast, in lipopolysaccharide (LPS)-stimulated cells, the higher concentrations of globularifolin suppressed NF-κB expression dose-dependently and a significant decrease was observed at 200 μM concentration. A positive correlation was found between increased neopterin and NF-κB activity (p <0.01). Similarly, a positive correlation was observed between neopterin levels in mitogen-induced cells and NF-κB activity in LPS-stimulated cells after treatment with globularifolin (p=0.001). The free radical scavenging capacity of globularifolin evaluated by Oxygen Radical Absorbance Capacity (ORAC) assay showed relative ORAC values of 0.36±0.05 μmol Trolox equivalent/μmol. All together, results show that natural antioxidant globularifolin might represent a potential immunomodulatory as well as proliferative agent, which deserves further in vitro and in vivo studies.

Amygdalin in bitter and sweet seeds of apricots

Hydrogen cyanide (HCN) poisoning due to amygdalin (AMY) in apricot seeds is one of the public health issues in Turkey. The aim of this study was to investigate the AMY content of 13 different apricot seeds including bitter and sweet ones, and which are either sulfurized or roasted. The AMY content was determined by a high-performance liquid chromatography. Release of HCN was predicted and total amount of seeds which can cause poisoning was calculated. The mean AMY content of bitter seeds was 26 ± 14 mg g−1 and that of sweet seeds was 0.16 ± 0.09 mg g−1. The consumption of small amounts of bitter seeds may cause cyanide poisoning.

Antimutagenic and anticlastogenic effects of Turkish Black Tea on TA98 and TA100 strains of Salmonella typhimurium (in vitro) and mice (in vivo)

Abstract Context: Black tea has been reported to have significant antimutagenic and anticarcinogenic properties associated with its polyphenols theaflavins (TF) and thearubigins (TR). Similarly, Turkish black tea (TBT) also contains a considerable amount of TF and TR. Objective: This study investigated the mutagenic, antimutagenic and anticlastogenic properties of TBT. Materials and methods: The mutagenic and antimutagenic effects of TBT (10 to 40000 μg/plate) were investigated in vitro on Salmonella strains TA98 and TA100 with and without S9 fraction. Anticlastogenic effect was studied at concentrations of 300–1200 mg/kg TBT extract by chromosomal aberrations (CA) assay from bone marrow of mice. Results: The results of this study did not reveal any mutagenic properties of TBT. On the contrary, TBT extract exhibited antimutagenic activity at >1000 μg/plate concentrations in TA98 strain with and without S9 activation (40% inhibition with S9 and 27% without S9). In TA100 strain, the antimutagenic activity was observed at >20,000 μg/plate TBT extracts without S9 activation (28% inhibition) and at >1000 μg/plate with S9 activation (59% inhibition). A significant decrease in the percentage of aberrant cells (12.33% ± 1.27) was observed in dimethylbenz(a)anthracene (DMBA) plus highest concentration (1200 mg/kg) of TBT extract-treated group when compared to only DMBA-treated group (17.00% ± 2.28). Discussion and conclusion: Results indicated that TBT can be considered as genotoxically safe, because it did not exert any mutagenic and clastogenic effects. As a result, TBT exhibited antimutagenic effects more apparently after metabolic activation in bacterial test system and had an anticlastogenic effect in mice.

Bioactivites of two common polyphenolic compounds: Verbascoside and catechin.

Abstract Context: Natural products can present remarkable biological and pharmacological activities. In traditional medicine, plants have been used historically in treating cancer, infections, and other inflammatory conditions. Objective: Verbascoside and catechin are widespread polyphenolic plant compounds that could play a role in the anti-inflammatory and health-promoting effects of plants and plant extracts. Materials and methods: This study compares the potential cytotoxic effects of polyphenols verbascoside and catechin (6.25–200 µM) on human peripheral blood mononuclear cells (PBMC) for 48 h and myelomonocytic THP-1 and THP-1 Blue cells for 24 h. The effects of the compounds on immune activation markers such as indoleamine 2,3-dioxygenase (IDO) activity as well as on neopterin formation and nuclear factor-κB (NF-κB) activation were investigated. Cytotoxicity of the compounds was tested using Cell-Titer Blue assay. Results: Verbascoside exhibited significant suppressive effects in mitogen-stimulated PBMC on tryptophan breakdown (>50 µM; IC50 value: 58.6 µM) and the production of neopterin (>6.25 µM; IC50 value: 217 µM). These effects correlated with a decline in cell viability, while THP-1 Blue cells were less sensitive. NF-κB activity was slightly enhanced at lower concentrations (<50 µM verbascoside) in stimulated cells and at the highest concentration used in unstimulated cells. Catechin had no relevant effects on cell viability and on the tested inflammation markers, except NF-κB activation in THP-1 Blue cells. Discussion and conclusion: The results obtained show that verbascoside and catechin represent effective compounds which interfere with immunobiochemical pathways that are highly relevant for immunosurveillance and competing virus infections.

The fruit extract of Berberis crataegina DC: exerts potent antioxidant activity and protects DNA integrity

BackgroundDried fruits of Berberis crataegina (Berberidaceae) have been frequently consumed as food garniture in Turkish cuisine, while its fruit paste has been used to increase stamina and in particular to prevent from cardiovascular dysfunctions in Northeastern Black Sea region of Turkey. This study investigated this folkloric information in order to explain the claimed healing effects as well as to evaluate possible risks.MethodsTotal phenolic, flavonoid and proanthocyanidin contents and antioxidant capacity of the methanolic fruit extract were evaluated through several in vitro assays. The cytotoxic and genotoxic effects of B. crataegina fruit extract were also assessed in both cervical cancer cell line (HeLa) and human peripheral blood lymphocytes.ResultsThe extract showed protective effects against ferric-induced oxidative stress and had a relatively good antioxidant activity. It also ameliorated the H2O2 mediated DNA damage in lymphocytes, suggesting the protective effect against oxidative DNA damage.ConclusionThe methanolic extract of B. crataegina fruits may be a potential antioxidant nutrient and also may exert a protective role against lipid peroxidation as well as oxidative DNA damage.

Developing and validation of an HPLC-DAD method for the determination of eight phenolic constituents in extract of different wine species

Objectives: A new HPLC method was developed and validated for the determination of some phenolic compounds; gallic acid, chlorogenic acid, epigallocatechin, caffeic acid, vanillin, p-coumaric acid, rutin, and quercetin in some local wine and fruit wine samples. Materials and Methods: Analyses were performed on a Zorbax Eclipse C18 column (4.6 x 150 mm, 3.5-µm particle size) using a gradient system. Mobile phase A was a 10-mM phosphoric acid solution and mobile phase B was methanol using a flow rate of 1 mL/min. Phenolic components were monitored using a DAD at three different wavelengths. Results: The developed and validated method was generally linear between the 1-100 ppm concentration range. Recovery values were obtained in the range of 95-105% and repetitive. The method was successfully applied to investigate the phenolic profiles of different wine samples. Conclusion: As a result of the study, an accurate, sensitive and reliable HPLC-DAD method was developed. The method was successfully used to determine the concentrations of antioxidant phenolic constituents from some local wine extracts.

Determination and Safety Evaluation of Furfural and Hydroxymethylfurfural in Some Honey Samples by Using a Validated HPLC-DAD Method

A novel high performance liquid chromatography method has been developed and validated for the simultaneous determination of furfural and hydroxymethylfurfural in 18 honey samples. An Agilent Poroshell 120 ECC18 150x3 mm 2.7μm particle sized column and isocratic elution with a 0.5 mL/min flow rate were used. The mobile phase was 10mM pH 2.5 phosphate buffer and acetonitrile and monitoring of analytes was carried on using a DAD detector at 284 nm wavelength. The method was validated according to USP guideline in terms of accuracy, precision, specificity, linearity and range\ robustness and ruggedness. According to the obtained results, the concentration levels of hydroxymethylfurfural were between 19.56-209.42 mg/kg in honey samples. Observed concentration values of HMF for 5 honey samples were higher than requirements and the highest level of hydroxymethylfurfural was observed in a thyme honey sample (209.42 mg/kg). The concentration values of furfural found in honey samples were in the range of 0.34-2.23 mg/kg. The highest level of furfura was determined in the thyme honey sample (2.23 mg/kg) also containing the highest concentration of hydroxymethylfurfural. In this study, the margins of exposure to furfural were also calculated for investigated honey samples. The margins of exposure for all analyzed samples were above the value of 100, indicating the safety of samples regarding to furfural exposure. The excessive hydroxymethylfurfural contents in some samples is a concerning point for public health and the national authority needs to increase its supervision on the honey.