The Experts below are selected from a list of 99 Experts worldwide ranked by ideXlab platform
Bertrand Matthäus - One of the best experts on this subject based on the ideXlab platform.
-
Phenolic compounds of three unconventional Sudanese oils
Acta scientiarum polonorum. Technologia alimentaria, 2015Co-Authors: Abdalbasit Adam Mariod, Bertrand Matthäus, Karl Eichner, Ismail HusseinAbstract:Background. The total amount and content of phenolic and flavonoid compounds using the Folin-Ciocalteu and Aluminum chloride methods of the methanolic extracts of Sclerocarya birrea oil (SCO), Melon bug oil (MBO), and Sorghum bug oil (SBO) were studied. Material and methods. Dry samples of Sclerocarya birrea, Aspongopus vidiuatus and Agonoscelis pubescens were used in this study. The oil was extracted using n-hexane following AOCS method. The phenolic compounds were extracted following a well known method and the total amounts of phenolic and flavonoids were determined using Folin-Ciocalteau and aluminum chloride methods, respectively and were identified by HPLC. Results. The concentration of total phenolic compounds was determined as 3.3, 20.7 and 0.9 mg/100 g oil, in SCO, MBO and SBO, respectively, calculated as gallic acid equivalents. The polar fraction of the three oils was separated using solid phase extraction method. The variation of simple and complex oils phenols studied by high-performance liquid chromatography with diode-array detection (DAD) using sephadex eluted by acetone revealed six phenolic compounds which were identified as vanillic acid, Callistephin, sinapic acid, t-cinnamic acid, epicatechin, and luteolin in SCO, and four phenolic compounds were identified as vanillin, sinapic acid, o-coumaric acid, and quercetin, in SBO, while in MBO four phenolic compounds were identified as t-cinnamic, syringic acid, quercetin and pelargonin. Conclusions. The phenolic compounds found in SCO, SBO, and MBO can be divided into phenolic compounds and flavonoids.
-
fatty acids tocopherols sterols phenolic profiles and oxidative stability of cucumis melo var agrestis oil
Journal of Food Lipids, 2008Co-Authors: Abdalbasit Adam Mariod, Bertrand MatthäusAbstract:Oil extracted from the seeds of Cucumis melo var. agrestis, collected from Ghibaish (sandy soil) and Gezira (heavy clay soil) provinces in Sudan, was studied in terms of the profile of fatty acids, tocopherols and sterols as well as phenolic compounds and oxidative stability by Rancimat (Metrohm AG, Herisau, Switzerland). The predominant fatty acid was 18:2n-6, representing 61.3 and 61.4% for Ghibaish and Gezira samples, respectively. There were no variations among the contents of 16:0, 18:0, 18:1n-9 and 18:2n-6 between the two samples. γ-Tocopherol was the predominant tocopherol in both samples, representing 80.7 and 77.6% of the total tocopherols, respectively, followed by α-tocopherol at 18 and 21%, respectively. Total sterol content was 3,879.0 and 3,785.0 mg/kg for Ghibaish and Gezira samples, respectively. The main sterol of the two oils was β-sitosterol. The two samples showed an oxidative stability of 5.9 and 5.7 h, respectively. The content of total phenolic compounds was determined in each sample according to the Folin-Ciocalteau method as 33.0 and 31.9 mg/g of dry product, respectively. The phenolic compounds of the oil were separated using a solid phase extraction. The fractions were studied by high-performance liquid chromatography with diode-array detection, which revealed four peaks in the two samples. The major components were catechin, vanillic acid, sinapic acid and Callistephin. There was little variability according to location between the two samples. PRACTICAL APPLICATIONS Two samples from dried seeds of Cucumis melo var. agrestis were collected. Seeds were crushed and ground using a grinding mill; the oil was extracted from the ground seeds by extraction with petroleum ether in a Soxhlet apparatus, and the physicochemical properties of C. melo var. agrestis oil were determined. The fatty acid and sterol composition were investigated using gas chromatography; the different tocopherol homologs were identified by high-performance liquid chromatography (HPLC), and the oil oxidative stability was studied by Rancimat (Metrohm AG, Herisau, Switzerland) apparatus. The phenolic compounds were extracted from the obtained oil and then identified by HPLC with diode-array detection.
D Balamurugan - One of the best experts on this subject based on the ideXlab platform.
-
Performance analysis of $$\hbox {TiO}_{2}$$ TiO 2
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength ( f ), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ ( Δ G inject ) and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ ( Δ G regen ) . The short-circuit current density $$({J}_{\mathrm{sc}})$$ ( J sc ) , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ ( λ total ) and open-circuit voltage $$({V}_{\mathrm{oc}})$$ ( V oc ) were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications. Graphical Abstract
-
performance analysis of hbox tio _ 2 tio 2 flavylium compound based dye sensitized solar cell dssc a dft tddft approach
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength (f), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ . The short-circuit current density $$({J}_{\mathrm{sc}})$$ , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ and open-circuit voltage $$({V}_{\mathrm{oc}})$$ were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications.
-
Performance analysis of $$\hbox {TiO}_{2}$$ TiO 2 -flavylium compound-based dye-sensitized solar cell (DSSC): a DFT–TDDFT approach
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength (f), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ . The short-circuit current density $$({J}_{\mathrm{sc}})$$ , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ and open-circuit voltage $$({V}_{\mathrm{oc}})$$ were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications.
Abdalbasit Adam Mariod - One of the best experts on this subject based on the ideXlab platform.
-
Phenolic compounds of three unconventional Sudanese oils
Acta scientiarum polonorum. Technologia alimentaria, 2015Co-Authors: Abdalbasit Adam Mariod, Bertrand Matthäus, Karl Eichner, Ismail HusseinAbstract:Background. The total amount and content of phenolic and flavonoid compounds using the Folin-Ciocalteu and Aluminum chloride methods of the methanolic extracts of Sclerocarya birrea oil (SCO), Melon bug oil (MBO), and Sorghum bug oil (SBO) were studied. Material and methods. Dry samples of Sclerocarya birrea, Aspongopus vidiuatus and Agonoscelis pubescens were used in this study. The oil was extracted using n-hexane following AOCS method. The phenolic compounds were extracted following a well known method and the total amounts of phenolic and flavonoids were determined using Folin-Ciocalteau and aluminum chloride methods, respectively and were identified by HPLC. Results. The concentration of total phenolic compounds was determined as 3.3, 20.7 and 0.9 mg/100 g oil, in SCO, MBO and SBO, respectively, calculated as gallic acid equivalents. The polar fraction of the three oils was separated using solid phase extraction method. The variation of simple and complex oils phenols studied by high-performance liquid chromatography with diode-array detection (DAD) using sephadex eluted by acetone revealed six phenolic compounds which were identified as vanillic acid, Callistephin, sinapic acid, t-cinnamic acid, epicatechin, and luteolin in SCO, and four phenolic compounds were identified as vanillin, sinapic acid, o-coumaric acid, and quercetin, in SBO, while in MBO four phenolic compounds were identified as t-cinnamic, syringic acid, quercetin and pelargonin. Conclusions. The phenolic compounds found in SCO, SBO, and MBO can be divided into phenolic compounds and flavonoids.
-
fatty acids tocopherols sterols phenolic profiles and oxidative stability of cucumis melo var agrestis oil
Journal of Food Lipids, 2008Co-Authors: Abdalbasit Adam Mariod, Bertrand MatthäusAbstract:Oil extracted from the seeds of Cucumis melo var. agrestis, collected from Ghibaish (sandy soil) and Gezira (heavy clay soil) provinces in Sudan, was studied in terms of the profile of fatty acids, tocopherols and sterols as well as phenolic compounds and oxidative stability by Rancimat (Metrohm AG, Herisau, Switzerland). The predominant fatty acid was 18:2n-6, representing 61.3 and 61.4% for Ghibaish and Gezira samples, respectively. There were no variations among the contents of 16:0, 18:0, 18:1n-9 and 18:2n-6 between the two samples. γ-Tocopherol was the predominant tocopherol in both samples, representing 80.7 and 77.6% of the total tocopherols, respectively, followed by α-tocopherol at 18 and 21%, respectively. Total sterol content was 3,879.0 and 3,785.0 mg/kg for Ghibaish and Gezira samples, respectively. The main sterol of the two oils was β-sitosterol. The two samples showed an oxidative stability of 5.9 and 5.7 h, respectively. The content of total phenolic compounds was determined in each sample according to the Folin-Ciocalteau method as 33.0 and 31.9 mg/g of dry product, respectively. The phenolic compounds of the oil were separated using a solid phase extraction. The fractions were studied by high-performance liquid chromatography with diode-array detection, which revealed four peaks in the two samples. The major components were catechin, vanillic acid, sinapic acid and Callistephin. There was little variability according to location between the two samples. PRACTICAL APPLICATIONS Two samples from dried seeds of Cucumis melo var. agrestis were collected. Seeds were crushed and ground using a grinding mill; the oil was extracted from the ground seeds by extraction with petroleum ether in a Soxhlet apparatus, and the physicochemical properties of C. melo var. agrestis oil were determined. The fatty acid and sterol composition were investigated using gas chromatography; the different tocopherol homologs were identified by high-performance liquid chromatography (HPLC), and the oil oxidative stability was studied by Rancimat (Metrohm AG, Herisau, Switzerland) apparatus. The phenolic compounds were extracted from the obtained oil and then identified by HPLC with diode-array detection.
Ilhami Gulcin - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant and antiradical properties of selected flavonoids and phenolic compounds
Biochemistry Research International, 2017Co-Authors: Zubeyir Huyut, şukru Beydemir, Ilhami GulcinAbstract:Phenolic compounds and flavonoids are known by their antioxidant properties and one of the most important sources for humans is the diet. Due to the harmful effects of synthetic antioxidants such as BHA and BHT, natural novel antioxidants have become the focus of attention for protecting foods and beverages and reducing oxidative stress in vivo. In the current study, we investigated the total antioxidant, metal chelating, Fe3+ and Cu2+ reduction, and free radical scavenging activities of some phenolic and flavonoid compounds including malvin, oenin, ID-8, silychristin, Callistephin, pelargonin, 3,4-dihydroxy-5-methoxybenzoic acid, 2,4,6-trihydroxybenzaldehyde, and arachidonoyl dopamine. The antioxidant properties of these compounds at different concentrations (10–30 μg/mL) were compared with those of reference antioxidants such as BHA, BHT, α-tocopherol, and trolox. Each substance showed dose-dependent antioxidant activity. Furthermore, oenin, malvin, arachidonoyl dopamine, Callistephin, silychristin, and 3,4-dihydroxy-5-methoxybenzoic acid exhibited more effective antioxidant activity than that observed for the reference antioxidants. These results suggest that these novel compounds may function to protect foods and medicines and to reduce oxidative stress in vivo.
-
Inhibition properties of some flavonoids on carbonic anhydrase I and II isoenzymes purified from human erythrocytes.
Journal of Biochemical and Molecular Toxicology, 2017Co-Authors: Zubeyir Huyut, şukru Beydemir, Ilhami GulcinAbstract:Carbonic anhydrases (CAs, E.C.4.2.1.1) play a critical role in many important physiological events and treatment of some diseases. Flavonoids or phenolic compounds have been discovered as novel CAs inhibitors instead of the traditional sulfonamides, with different binding to CAs, pro-drug activities, and new inhibition mechanisms. Here, we investigated the inhibition effects of some flavonoids including malvin, Callistephin, oenin, pelargonin, silychristin, and 1-(4-methoxyphenyl)-2-methyl-3-nitro-1-H-indol-6-ol (ID-8) against hCA I and II, which purified from human erythrocytes by affinity column chromatography. Both hCA isoenzymes were inhibited by flavonoids, with IC50 and Ki values in the range of 2.34 nM to 346.5 μM and 51.01–99.55 μM for hCA I and 86.60–750.00 μM for hCA II, respectively. These results showed that flavonoids especially malvin and oenin effectively inhibited hCA I and II isoenzymes. Hence, they may be used as an effective CA inhibitor in medical applications for treatment of certain diseases such as glaucoma, in the future.
Muthaiyan Lakshmanakumar - One of the best experts on this subject based on the ideXlab platform.
-
Performance analysis of $$\hbox {TiO}_{2}$$ TiO 2
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength ( f ), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ ( Δ G inject ) and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ ( Δ G regen ) . The short-circuit current density $$({J}_{\mathrm{sc}})$$ ( J sc ) , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ ( λ total ) and open-circuit voltage $$({V}_{\mathrm{oc}})$$ ( V oc ) were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications. Graphical Abstract
-
performance analysis of hbox tio _ 2 tio 2 flavylium compound based dye sensitized solar cell dssc a dft tddft approach
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength (f), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ . The short-circuit current density $$({J}_{\mathrm{sc}})$$ , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ and open-circuit voltage $$({V}_{\mathrm{oc}})$$ were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications.
-
Performance analysis of $$\hbox {TiO}_{2}$$ TiO 2 -flavylium compound-based dye-sensitized solar cell (DSSC): a DFT–TDDFT approach
Journal of Computational Electronics, 2018Co-Authors: Muthaiyan Lakshmanakumar, S Sriram, D BalamuruganAbstract:The computational study of flavylium compound consists of anthocyanin pigments: Callistephin, Chrysanthemin, oenin and mytrillin, and anthocyanidin pigments: peonidin and petunidin dyes are used to identify the potential photosensitizer for dye-sensitized solar cell (DSSC). Density functional theory is adopted to study methoxyl and hydroxyl groups in six pigments. The computed results of six dyes show good oscillator strength (f), light harvesting efficiency, electron injection $$(\Delta G^\mathrm{{inject}})$$ and electron regeneration $$({\Delta } G^\mathrm{{regen}})$$ . The short-circuit current density $$({J}_{\mathrm{sc}})$$ , total reorganization energy $$({\uplambda }_{\mathrm{total}})$$ and open-circuit voltage $$({V}_{\mathrm{oc}})$$ were also discussed. Intermolecular charge transfer of six dyes was examined using frontier molecular orbital. However, Peonidin/Titanium dioxide system has shown a significant response in density of states. Hence, this study confirms peonidin dye can be used as a photosensitizer for DSSC applications.
