Papers by Mustafa A YILMAZ
Journal of the Institute of Science and Technology, 2018
A comprehensive LC-MS/MS method was developed and validated for the quantification of eight plant... more A comprehensive LC-MS/MS method was developed and validated for the quantification of eight plant phytochemicals (cynarin, caffeic acid, syringic acid, p-coumaric acid, o-coumaric acid, vanillic acid, ferulic acid, chlorogenic acid) in plants. The developed analytical method was fully validated in terms of linearity, accuracy (recovery), inter and intra-day precision (repeatability), limits of detection and quantification (LOD/LOQ) and relative standard uncertainty (U% at 95% confidence level (k=2)). Chromatographic separation was performed on a reverse phased UHPLC. MS detection was performed using a triple quadrupole mass spectrometer and negative or positive ionization modes were optimized for each analyte. Multiple reaction monitoring (MRM) was used to quantify the analytes, related molecular ions and transition ions were optimized. After method validation, the phytochemical composition of methanolic extracts of some edible plants including artichoke (Cynara scolymus L.), broccoli (Brassica Oleracea var. Italica), cauliflower (Brassica Oleracea var. Botrytis) and tumble thistle (Gundelia Tournefortii) were investigated by the developed and validated LC-MS/MS method. Among the analysed plants, artichoke was by far the richest one in terms of phenolics. Additionally, chlorogenic acid was the most abundant phenolic compound in all plants. Although the studied edible plants were chosen as real samples, the developed LC-MS/MS method is applicable to a wide range of species in plant kingdom.
Tropical Journal of Pharmaceutical Research, 2016
Purpose: To characterise the phytochemical profile of whole plants of Centaurea balsamita, C. dep... more Purpose: To characterise the phytochemical profile of whole plants of Centaurea balsamita, C. depressa and C. lycopifolia with LC-ESI-MS/MS, and as well as their antioxidant, anticholinesterase and antimicrobial activities. Methods: Organic and aqueous extracts of the three Centaurea species were evaluated for DPPH free radical, ABTS cation radical scavenging and cupric reducing antioxidant capacity (CUPRAC). Acetyland butyryl-cholinesterase enzyme inhibition abilities of the extracts using petroleum ether, acetone, methanol and water were studied to determine anticholinesterase activity, while antimicrobial activity was determined by disc diffusion method using appropriate antimicrobial standards and organisms. The phytochemical components of the methanol extracts were assessed by LC-MS/MS. Results: The methanol extract of C. balsamita exhibited much higher DPPH free and ABTS cation radicals scavenging activities (with IC50 of 62.65 ± 0.97 and 24.21 ± 0.70 mg/ml, respectively) than the other extracts. The petroleum ether extracts of the plant species exhibited moderate inhibitory activity against butyrylcholinesterase enzymes while the acetone extract of C. balsamita showed good antifungal activity against Candida albicans. Quinic acid (17513 ± 813 µg/g, 63874 ± 3066 µg/g and 108234 ± 5195 µg/g) was the major compound found in the methanol extracts of C. balsamita, C. depressa and C. Lycopifolia, respectively. Conclusion: These results indicate quinic acid is the major compound in the three plant species and that Centaurea balsamita has significant antioxidant, anticholinesterase and antimicrobial properties. Further studies to identify the compounds in the extracts responsible for the activities are required.
Background: Halophytes are considered as valuable sources of traditional drugs in different count... more Background: Halophytes are considered as valuable sources of traditional drugs in different countries. Purpose: The present study aimed to evaluate biological and chemical fingerprints of three halophytes (Arthrocnemum macrostachyum (Moric.) C, Koch, Halimione portulacoides (L.) Aellen and Salicornia europaea L.). Materials and methods: The antioxidant and enzymatic inhibitory potential (acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase, and tyrosinase) were assessed. The total phenolic, flavonoid contents, and the chemical profiles were appraised using the ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry. Molecular docking was conducted to provide additional insights of molecular interactions of the enzymes/phytochemicals. Results: Ethyl acetate extract was the most efficient extract, with A. macrostachyum being the most potent towards DPPH and ABTS radicals and phosphomolybdenum assay. Ethyl acetate extract of A. macrostachyum was also the best reducing agent (CUPRAC and FRAP assays). Methanol and ethyl acetate extract of A. macrostachyum, H. portulacoides, and S. europaea showed significant enzyme inhibition potential. Ethyl acetate extract of A. macrostachyum showed the highest total phenolic (29.54 ± 0.78 mgGAEs/g extract) while the ethyl acetate extract of S. europaea was more abundant in flavonoids (18.26 ± 0.11 mgREs/g extract). Phytochemical profiling allowed the identification of several components in the methanolic extracts (16 in A. macrostachyum, 14 in H. portulacoides, and 11 in S. europaea), with quinic acid, p-coumaric acid, and rhamnetin being most abundant. Docking studies revealed that the above compounds showed scores for the enzymes tested. Conclusion: The three halophytes studies could be considered as potential sources of biologically-active compounds for novel phytopharmaceuticals development. Phytomedicine 38 (2018) 35-44 0944-7113/
The extracts of powdered root and nutgall of Iraqian Aleppo oak (Q. infectoria) were obtained by ... more The extracts of powdered root and nutgall of Iraqian Aleppo oak (Q. infectoria) were obtained by using three different solvents along with two extraction methods. Liquid chromatography and tandem mass spectrometry (LC-MS/MS) was implemented to identify phytochemicals in the extracts. Antioxidant activity was determined by DPPH radical scavenging activity. Also, for measurement of antibacterial activity, disc diffusion and microdilution assays were used. Specifically, the nutgall extracts were found to have higher concentration of phenolic acid contents, and to some extent flavonoids and greater antioxidant and antimicrobial activities in comparison with the root extracts. Furthermore, microwave extraction technique was proven to be much more effective than conventional one in view of extraction yield for both plant parts used here.
The present work aimed to determine the chemical characterization of the aerial partand to assess... more The present work aimed to determine the chemical characterization of the aerial partand to assess full thickness excised wound healing activity of the fatty oil of Mentha piperita L. (MPFO) grown in Algerian eastern part. The fatty acid composition of M. piperita L. leaves hexane extract was analysed by GC-MS. Total thickness excised wound healing activity of hexane extract was carried out on the back of nine adult male New Zealand rabbits; comparing to a reference drug effects (Madecassol ® ).The treatments were repeated once daily until complete healing. For each four days of post-excision, the percentage of wound contraction was evaluated, and the different healing times were noted. The results showed that M. piperita L. leaves contain low levels of oil (1.79%), and GC/MS results of its oil have revealed the presence of different fatty acids among which the main constituents were oleic (43.16 ± 1.01%), palmitic (37.70 ± 0.94%) and linoleic (11.13± 0.45%) acids. The wound healing activity and the level of wound contraction were significantly higher in M. piperita L. fatty oil (MPFO) compared to untreated wounds. In addition, both of MPFO and Madecassol® accelerated significantly wound healing activity and their healing times were faster than CONT group. We conclude that M. piperita L. fatty oil promotes significantly (p< 0.05) wound contraction and reduces epithelization period in rabbit model. Center (DUBTAM) for their prodigious contributions. Références Adlouni A. 2010. L'huiled'argan, de la nutrition à la santé. Phytothérapie 8(2), 89-97. http://dx.
Methanolic extracts of Moltkia aurea Boiss. (MA) and Moltkia coerulea (Willd.) Lehm. (MC) were in... more Methanolic extracts of Moltkia aurea Boiss. (MA) and Moltkia coerulea (Willd.) Lehm. (MC) were investigated for their antioxidant capacity and enzymatic inhibitory potential against acetylcholinesterase, butyrylcholinesterase, a-amylase, a-glucosidase, and tyrosinase in vitro. MA and MC were also explored for their antimicrobial effect, as well as for their possible genotoxic/antigenotoxic potential on Drosophila melanogaster in vivo. The total bioactive components (phenolic (TPC) and flavonoid contents (TFC)) were determined and liquid chromatography-tandem mass spectrometry (LC-MS/MS) metabolite profiling of MA and MC appraised. The plausible docking poses of bioactive compounds to key enzymes were further studied using molecular modelling approach. MA proved to be a better antioxidant with higher TPC and TFC compared to MC. Protocatechuic acid, rutin, hesperidin and malic acid were the most abundant in these extracts. Both MA and MC exhibited antigenotoxic potential with a %R in DNA damage of 60.90 and 53.14% respectively. The docking studies revealed that rutin, hesperidin, and rosmarinic acid have the best scores for all the enzymes tested. MA and MC were found to be rich in phytochemicals with potent antioxidant, antimicrobial, and antigenotoxic activities that can be further studied for the management of neurodegenerative complications, diabetes, and hyperpigmentation.
Present work aims to determine the chemical profile and some biological activity of three endemic... more Present work aims to determine the chemical profile and some biological activity of three endemic Astragalus species from Anatolia. The chemical contents of Astragalus leporinus var. hirsutus, Astragalus distinctissimus and Astragalus schizopterus were characterised by LC-MS/MS and GC-MS. In terms of biological activity; the antioxidant, anticholinesterase, antimicrobial and cytotoxic activities were determined. Additionally, the antioxidant properties of the major components were also determined and compared to the antioxidant capacities of these extracts. The most abundant flavonoids in these Astragalus species were determined as rutin (1028.276-13351.76 µg/g extract) and hesperidin (1604.348-9695.435 µg/g extract). A high amount of quinic acid (111302.774 µg/g extract) was detected in A. schizopterus methanol extract. Palmitic acid (C16:0) was found to be the major compound in A. leporinus var. hirsutus (32.9%), A. distinctissimus (32.5%), and A.schizopterus (23.4%). A. schizopterus methanol extract exhibited the highest antioxidant effect in lipid peroxidation (19.62±0.29), DPPH free (54.61±0.38) and ABTS cation radicals scavenging activity (22.01±0.07), and CUPRAC assays. Among all of the extracts, only A. leporinus var. hirsutus petroleum ether extract showed moderate inhibitory activity against acetyl-and butyryl-cholinesterase enzymes. The methanol extracts of the plants exhibited moderate activity against C. albicans. A. leporinus var. hirsutus methanol extract indicated the most viability against L929 fibroblast cells, and the highest cytotoxic effect against A549 cells. In consideration of our findings , these Astragalus species used as animal feed could be a source of naturally, biologically active agents that can be used in food and pharmaceutical industry.
The purpose of the present work was to determine the phenolic and the fatty acids profiles by LC-... more The purpose of the present work was to determine the phenolic and the fatty acids profiles by LC-MS/MS and GC/MS with their antioxidant, anticholinesterase and antimicrobial activities, and aflatoxin contents of Malva neglecta and Malvella sherardiana. The phenolic contents of M. neglecta and M. sherardiana were determined by LC-MS/MS. Malic and 4-OH benzoic acids were found to be the most abundant compounds in M. neglecta and M. sherardiana, respectively. On the other hand, essential oil and fatty acid compositions were determined by GC/MS analysis. The methanol extracts of the plants showed the highest effect in all antioxidant assays in this study. The methanol extract of M. neglecta showed the highest activity among the petroleum ether, acetone, methanol and water extracts against acetyl-and butyryl-cholinesterase enzymes (53.68% and 63.95% inhibition ratio, respectively). The acetone extracts of M. neglacta and M. sherardiana exhibited moderate activity against C. albicans with 18 and 17 mm inhibion zone diameter, respectively. The results of the present study is also showed that the M. neglecta and M.
This paper is the first phytochemical and ABTS cation radical decolorisation activity, cupric red... more This paper is the first phytochemical and ABTS cation radical decolorisation activity, cupric reducing antioxidant capacity, anticholinesterase and DNA damage protection effect of endemic Verbascum pinetorum (Boiss.) O. Kuntze. Phenolic profile of V. pinetorum were qualified and quantified by UHPLC-ESI-MS/MS analysis. Malic acid (47250.61±2504.28 µg/g) and luteolin (7651.96±527.98 µg/g) were found as most abundant compounds for metanol and acetone extracts, respectively. Fatty acid and essential oil compositions were determined by GC-MS analysis. The main components of fatty acid were found to be palmitic (27.1%) and stearic (22.1%) acids. The main compounds of the essential oil were cineole (16.9%) and α-selinene (16.4%). The acetone extract was found to be more active than BHT used as a standard in β-carotene-linoleic acid test system. In DPPH free radical scavenging activity, the acetone and methanol extracts showed higher activity than BHT at all tested concentrations. The acetone, methanol and water extracts showed strong inhibition while the acetone extract showed better activity than BHT and α-tocopherol which were used as standards in ABTS cation radical scavenging and cupric reducing antioxidant capacity assays, respectively. All extracts were found to be inactive in antialzheimer activity. The acetone extract exhibited moderate antimicrobial activity against C. albicans. The methanol extract of V. pinetorum were found no significant effect on DNA cleavage protection.
In this study, Ultra High Performance Electrospray Ionization Ion Trap Time of Flight Mass Spectr... more In this study, Ultra High Performance Electrospray Ionization Ion Trap Time of Flight Mass Spectrometry (UHPLC-ESI-IT-TOF MS) method is used to screen the polymer additives in drinking water that is stored in Polyethylene Terephthalate (PET) bottles. After directly analyzing the commercially available water samples, 3 polymer additives (chimassorb 81, irgafos 168 and oleamide) were detected. However, after exposure to sunshine for 8 days, two additional polymer additives (antioxidant 2246 and Butylated Hydroxytoluene (BHT)) were detected besides the former three additives.
Methods: Organic and aqueous extracts of the three Centaurea species were evaluated for DPPH free... more Methods: Organic and aqueous extracts of the three Centaurea species were evaluated for DPPH free radical, ABTS cation radical scavenging and cupric reducing antioxidant capacity (CUPRAC). Acetyland butyryl-cholinesterase enzyme inhibition abilities of the extracts using petroleum ether, acetone, methanol and water were studied to determine anticholinesterase activity, while antimicrobial activity was determined by disc diffusion method using appropriate antimicrobial standards and organisms. The phytochemical components of the methanol extracts were assessed by LC-MS/MS. Results: The methanol extract of C. balsamita exhibited much higher DPPH free and ABTS cation radicals scavenging activities (with IC50 of 62.65 ± 0.97 and 24.21 ± 0.70 mg/ml, respectively) than the other extracts. The petroleum ether extracts of the plant species exhibited moderate inhibitory activity against butyrylcholinesterase enzymes while the acetone extract of C. balsamita showed good antifungal activity against Candida albicans. Quinic acid (17513 ± 813 µg/g, 63874 ± 3066 µg/g and 108234 ± 5195 µg/g) was the major compound found in the methanol extracts of C. balsamita, C. depressa and C. Lycopifolia, respectively. Conclusion: These results indicate quinic acid is the major compound in the three plant species and that Centaurea balsamita has significant antioxidant, anticholinesterase and antimicrobial properties. Further studies to identify the compounds in the extracts responsible for the activities are required.
This paper is the first report about phytochemical analysis with LC-MS/MS and biological activiti... more This paper is the first report about phytochemical analysis with LC-MS/MS and biological activities of Verbascum flavidum (Boiss.) Freyn & Bornm. Rutin (1077.09±77.47 µg analyte/g extract) and chlorogenic acid (1012.42±97.18 µg analyte/g extract) were determined as the most abundant phenolics in V. flavidum. The main components of fatty acid were found to be palmitic (30.3%) and oleic acids (17.9%); while the major essential oils were determined as arachidic acid (16.4%) and α-selinene (8.9%) by GC-MS analysis. In DPPH free radical scavenging activity the methanol extract showed higher activity than BHT with 72.62% inhibition at 100 µg/mL concentration. The methanol and water extracts of V. flavidum showed 86.01 % and 87.39 % inhibition in ABTS cation radical scavenging assay at 100 μg/mL concentration, respectively. The methanol extract showed moderate activity against E. coli with 250±0.3 MIC value and with 15 mm inhibition zone diameter at 30 mg/mL concentration.
The aim of this study was to determine the chemical characterization and to assess full-thickness... more The aim of this study was to determine the chemical characterization and to assess full-thickness-excised wound-healing activity of the oil of Pistacia lentiscus L. fruits grown in Algeria. The fatty acid composition of P. lentiscus L. extracts were analyzed by GC-MS and their total protein amounts were determined by elemental analysis. Total thickness-excised wound-healing activity of hexane extract was carried out on rabbits; comparing oil and wax effects. The results showed that P. lentiscus L. fruits contain considerable levels of oil and protein. Additionally, oleic (46.91 ± 1.03, 48.34 ± 0.07) in hexane and cold pressure extracts, respectively, palmitic (25.75 ± 0.82, 25.44 ± 0.65) and linoleic (20.59 ± 0.03, 20.27 ± 0.81) acids were the major fatty acids. Wound-healing activity was significantly higher in P. lentiscus L. fatty oil compared to the wax, therefore, fats refining is wildly recommended.
The objectives of this study were to define the phenolic and fatty acid profiles, anticholinester... more The objectives of this study were to define the phenolic and fatty acid profiles, anticholinesterase, antioxidant, antimicrobial activities, and total phenolic-flavonoid contents of Lycopsis orientalis and Tragopogon latifolius var. angustifolius which have been used as food source and food supplement in Anatolia and have never been examined before. Rosmarinic and quinic acids (21.11 and 11.46 mg g -1 extract, respectively) were found to be the most abundant constituents in L. orientalis and T. latifolius var. angustifolius among the studied 27 compounds by liquid chromatography tandem mass spectrometry. In the fatty acid compositions of L. orientalis and T. latifolius var. angustifolius that were determined by gas chromatography mass spectrometry, oleic (29.1%) and palmitic (28.7%) acids were identified as the major components, respectively. The high antioxidant activity of the methanol extract of L. orientalis shows parallelism to its rosmarinic acid content. Besides, this extract showed medium anticholinesterase activity. The results of the present study proves that the L. orientalis might also be used as a food source due to its high phenolic acid content and strong antioxidant property.
Eating habits as well as physical exercise are very important for a healthy lifespan. Ramadan-typ... more Eating habits as well as physical exercise are very important for a healthy lifespan. Ramadan-type fasting, which is food and water avoidance during the daylight period for four weeks, has drawn attention due to its positive impacts on metabolism and health. The aim of this study was to compare the blood and urine catecholamine (CA) levels in fasting and non-fasting rats, in terms of stress response. A total of 20 male rats were randomly divided into a fasting group and a control group. Four weeks later, blood and urine samples were taken after decapitation. Analysis of CAs was done using high-performance liquid chromatography with florescence detection (HPLC-FLD). The dopamine (DA), adrenaline (ADR) and noradrenaline (NA) blood and urine concentrations were found to be higher in the fasting group compared to the control group, but the difference was statistically significant only for the blood DA levels (p < 0.05). In the fasting group, the blood values of ADR and NA correlated with each other but not with the DA levels, whereas there was correlation among the urine levels of DA, ADR and NA. In the control group, the blood and urine values of DA, ADR and NA correlated with each other. The differences observed in the blood and urine CAs indicate a specific regulation of CAs in Ramadan-type fasting, which needs to be investigated thoroughly in future studies.
In the present study, the methanolic extracts of Cytisopsis dorycniifolia and Ebenus hirsuta were... more In the present study, the methanolic extracts of Cytisopsis dorycniifolia and Ebenus hirsuta were analyzed for antioxidant, enzyme inhibitory, antimicrobial and antigenotoxic activities. The identification and quantification of phenolic compounds in these extracts were performed using liquid chromatography coupled with mass spectrometry (LC-MS/MS) technique, and the main components were hyperoside, rutin, hesperidin, tannic acid and p-coumaric acid. The extracts had remarkable biological effects. Generally, C. dorycniifolia had higher level of bioactive components and exhibited stronger in vitro antioxidant effects than E. hirsuta. E. hirsuta was active especially against bacteria Pseudomonas fluorescens and Agrobacterium tumefaciens and fungi Puncturella fastigiata, while C. dorycniifolia was active against bacteria E. faecalis and had moderate activity against Trichoderma species. The extracts displayed strong antigenotoxic effects (98.6% for E. hirsuta and 76.3% for C. dorycniifolia). Our findings suggested that C. dorycniifolia and E. hirsuta could be beneficial for the preparation of high-value pharmaceuticals and functional food ingredients.
The southeastern part of Turkey is quite rich, fertile and mature in terms of hydrocarbon seepage... more The southeastern part of Turkey is quite rich, fertile and mature in terms of hydrocarbon seepages. While the use of the related sources meet the energy demand, it damages the environment and human health. In this study, several geochemical methods were applied to analyze the hydrocarbon sepage samples obtained from seven towns in the province of Adiyaman where is very close to the oil production areas and located in the Southeastern part of Turkey. First of all, Total Organic Carbon (TOC), Rock Evil Paralysis, Gas Chromatography (GC) and Gas Chromatography Mass Spectrometry analyses (GC -MS) were performed for the samples in question. In the light of these results, oil/bitumen mechanisms, source rock correlations, formation and migration mechanisms of the related geological environments were found. Then, Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) analysis of Fe, Al, Mn, Mn, Zn, B, Pb, Ni, Cu metals were performed. Chemical and mineralogical features of the samples were investigated by IR and combined with ESR spectra. The samples display typical ESR spectra of Mn +2 ions hyperfine sextet whose last line was used to check the stones homogenity with respect to manganase content. In this study, heavy metal pollution and hydrocarbon compounds were determined to damage the environment and several suggestions were made to overcome the pollution and to enhance the productivity
This study represents the first report on the chemical composition and biological activity of Tri... more This study represents the first report on the chemical composition and biological activity of Trifolium angustifolium var. angustifolium. The major components of the essential oil were identified as hexatriacontene (23.0%), arachidic acid (15.5%) and α-selinene (10.0%). The main constituents of the fatty acid obtained from the petroleum ether extract were identified as palmitic acid (29.8%), linoleic acid (18.6%) and oleic acid (10.5%). In particular, the water extract exhibited higher activity than α-tocopherol and BHT, which were used as standards in the ABTS cation radical scavenging assay and indicated higher inhibitory effect against acetylcholinesterase enzyme than the reference compound, galanthamine but exhibited weak activity in β-carotene bleaching, DPPH-free radical scavenging, and cupric-reducing antioxidant capacity assays. The petroleum ether extract exhibited higher activity than α-tocopherol which was used as standard in the β-carotene bleaching method at concentration 100 μg/mL. The acetone extract exhibited higher activity than α-tocopherol which was used as standard cupric reducing antioxidant capacity (CUPRAC) method at 100 μg/mL concentration The acetone and methanol extracts were active on all microorganisms tested with a small zone diameter indicating weak activity.
Turkey is one of the most important centers of diversity for the genus Achillea L. in the world. ... more Turkey is one of the most important centers of diversity for the genus Achillea L. in the world. Keeping in mind the immense medicinal importance of phenols, in this study, three species growing in Turkey, A. coarctata Poir. (AC), A. kotschyi Boiss. subsp. kotschyi (AK) and A. lycaonica Boiss. & Heldr. (AL) were evaluated for their phenolic compositions, total phenolic contents (TPC), antioxidant properties, wound healing potencies on NIH-3T3 fibroblasts and cytotoxic effects on MCF-7 human breast cancer cells. Comprehensive LC-MS/MS analysis revealed that AK was distinctively rich in chlorogenic acid, hyperoside, apigenin, hesperidin, rutin, kaempferol and luteolin (2890.6, 987.3, 797.0, 422.5, 188.1, 159.4 and 121.2 µg analyte/g extract, respectively). The findings exhibited a strong correlation between TPC and both free radical scavenging activity and total antioxidant capacity (TAC). Among studied species, the highest TPC (148.00 mg GAE/g extract) and TAC (2.080 UAE),
In this study, it was aimed to investigate the chemical composition and antioxidant activities of... more In this study, it was aimed to investigate the chemical composition and antioxidant activities of two Euphorbia species. The major component of the fatty acid compositions obtained from the petroleum ether extracts was identified as palmitic acid for Euphorbia gaillardotii and Euphorbia macroclada. The main constituents of the essential oils were identified as arachidic acid for E. gaillardotii and tetratetracontane for E. macroclada. Among the 27 studied compounds, hesperidin, rutin, hyperoside and quinic, malic, gallic and tannic acids were found to be the most abundant compounds in the two Euphorbia species. The methanol extracts of E. gaillardotii and E. macroclada showed strong antioxidant activity in all tested methods. Particularly, IC 50 values of E. macroclada methanol extract that was the richest in terms of total phenolicflavonoid contents were found to be lower than a-tocopherol and butylated hydroxytoluene in b-carotene bleaching, 2,2-diphenyl-1-picrylhydrazyl free and ABTS cation radical scavenging methods.
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Papers by Mustafa A YILMAZ