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The Bifunctional Catalase-Phenol Oxidase of Mycothermus Thermophilum (MtCATPO) Increases the Antioxidant Capacities of its Ortho-Diphenolic Substrates and of Green and Black Tea Extracts
2021
Betül Söyler | Zümrüt Begüm Ögel
Catalase from the thermophilic fungus Mycothermus thermophilus is a bifunctional enzyme with a secondary phenol oxidase activity (CATPO). MtCATPO catalyses the oxidation of catechol, chlorogenic acid, caffeic acid and (+)-catechin to yield mainly dimers, and higher molecular weight oligomers and polymers. The role of this phenol oxidase activity is not known. Here, the antioxidant capacities (AC) of the phenolic substrates in the absence and presence of MtCATPO were compared. The oxidized products displayed enhanced AC reaching a maximum of 2.4-fold with catechol. Other phenol oxidases (laccase and tyrosinase) did not yield AC enhancement to the same extent. MtCATPO-treatment increased AC of green and black tea infusions, as well as water extracts of samples collected from a black tea production line up to 28%. The bifunctional MtCATPO appears to be an important antioxidant enzyme with a wide range of potential applications in the food, neutraceuticals and pharmaceuticals industry.
Show more [+] Less [-]Quantitative Analysis of Phenolic Compounds and Mineral Contents of Rosa canina L. Waste Seeds
2021
Kadriye Özlem Saygı
Natural products play an important role in medicine. They have been used extensively in folk medicine to treat various illnesses. In this work, quantitative analysis of phenolic compounds in methanol, acetonitrile and dichloromethane extracts of Rosa canina L. waste seeds were investigated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) LC-MS/MS. Mineral analysis of R. canina seeds was determined by inductively coupled plasma–atomic emission spectrometry (ICP-OES). Fe, Mn, K and Zn were found as chief elements. Quantitative analysis revealed that catechin was the major flavonoid in all extracts. This work offers a viewpoint for recycling the R. canina waste seeds into the economy due to their bioactive content.
Show more [+] Less [-]Studies of Phenolic Compounds Coupled to Minerals in Cocoa Beans of the “Mercedes” and “Forastero” Varieties from the Divo and Abengourou Regions (Côte d’Ivoire)
2022
Jean Constant Kouablan Karim | Suomion Justin Saki | Tehi Bernard Sea | Kouassi Aboutou Severin Kra | Guillaume Arthur Kouassi Loh Yoboue
The aim of this study is to contribute to the valorization of the cocoa bean varieties “Mercedes” and “Forastero” grown in Côte d’Ivoire. A comparative characterisation of phenolic compounds and minerals in the beans of the “Mercedes” and “Forastero” varieties from two major cocoa production areas of Côte d’Ivoire were determined. The phenolic compounds of cocoa beans were determined by high performance liquid chromatography (HPLC) and the minerals by atomic absorption spectrophotometer. The study showed that a significant difference at the 5% level was observed in the averages of minerals, cinnamic acid, protocatechic acid, quercetin, coumaric acid, rutin, ellagic acid, veratric acid, epicatechin, ferulic acid and naringenin. On the other hand, no significant difference at the 5% level was observed in the averages of arbutin, catechin, vanillic acid and caffeic acid in the bean kernels analysed in the Divo and Abengourou regions. The proportion of cinnamic acid is (6.18±0.63 mg/100g “Mercedes” Divo), that of ellagic acid is (18.48±0.44 mg/100g “Mercedes” Divo) and that of naringenin is (5.95±0.35 mg/100g “Mercedes” Divo). The amount of potassium is (7569.97±1.51 mg/kg “Forastero” of Abengourou) and that of iron is (179.9 ± 0.70 mg/Kg “Forastero” of Divo). The phenolic compounds and minerals in the cocoa bean samples analysed are highly correlated and rich in antioxidants. They would be beneficial for many biological functions. They can be recommended in pharmacology and cosmetics to fight against oxidative stress and cardiovascular diseases.
Show more [+] Less [-]Phenolic compound and antioxidant activity of two slightly consumed wild mushrooms (Lentinus squarrosulus and Auricularia politrich) in three regions from center Ivory Coast
2021
Hermann Fourier Atta Anno | Hyacinthe Attoh Anon | Koffi Amoin Gisèle | Appolinaire Kouamé Kouassi | Jean Parfait Eugène Kouadio
Mushrooms contain a variety of secondary metabolites, including various phenolic compounds, which have been shown to act as excellent antioxidants. In this study, the contents of total phenolic, flavonoids and tannins of mushrooms methanolic extracts were evaluated by colorimetric assays to ranges of 277.36±0.66 to 420.86±0.90 mg (GAE)/100g DW; 31.99±0.90 to 90.90±0.07mg (QE)/100g DW and 150.61±0.16 to 220.47±1.01mg (TAE)/100g DW respectively. HPLC-profiles of methanolic extracts indicated that the individual phenolic compounds found to the samples of the species of mushrooms that are Lentinus squarrosulus and Auricularia politrich revealed us that gallic acid, catechin, acid ρ-hydroxybenzoїc, acid ellagique and naringerin were presented to the level of the two species. With respect to organic acids, the results showed that citric acid and fumaric acid was the major organic acid in all the samples of both mushrooms species. The methanolic extracts of the two mushrooms exhibited the high DPPH radical scavenging activities ranging from 34.10±1.12 to 58.95±0.52%. These data indicated that these mushrooms could constitute a potential good source of natural antioxidant for the local population.
Show more [+] Less [-]Phenolic Contents of Different Potato Genotypes Grown in the Central Northern Region in Turkey
2021
Yasin Bedrettin Karan | Tarık Balkan | Ramazan Erenler
Potato (Solanum tuberosum L.) is one of the most significant vegetable crops for humans along with corn, wheat, and rice. In this study, quantitative analysis of phenolic compounds was carried out for 21 promising potato clones and three commercial cultivars. LC–MS/MS was used for the chemical analyses. The TOGU 3/518 clone had the highest level of 4-hydroxybenzoic acid as 138.51 ± 7.35 µg/kg. TOGU 12/29 and TOGU 2/198 clones, on the other hand, had 126.24 ± 2.29 and 125.29 ± 2.74 µg/kg of 4-hydroxybenzoic acid, respectively. Salicylic acid which is a pharmaceutically significant compound was found in TOGU 3/518 clone (125.66 ± 11.51 µg/kg) as a major product. This compound was also found in TOGU 2/198 (111.27 ±1.31 µg/kg) and TOGU 12/29 clones (111.07 ± 3.68 µg/kg) as the third and fourth most abundant. In terms of caffeic acid, TOGU 3/110 clone contained the highest level (42.50 ± 3.73 µg/kg). While TOGU 7/146 clone included the most protocatechuic acid (53.98 ± 1.47 µg/kg), TOGU 3/480 clone consisted of most gentisic acid (30.79 ± 0.51 µg/kg). Quercetin, an important flavonoid found many aromatic and medicinal plants, was highest in TOGU 12/29 clone (6.27 ± 0.15 µg/kg).
Show more [+] Less [-]Phenolic Compounds and Antioxidant Activity of Local Cultivar of Apple (Malus domestica Borkh) in East of Turkey
2020
Gülden Gökşen | Fevzi Keleş
Apples, rich in phenolic compounds, are widely grown in abundance and consumed as fruit which reduces the risk of many illnesses. In this study, physico-chemical properties old apple cultivars from east of Turkey were investigated. Identification and quantification of phenolic compounds of freeze dried fresh apple varieties (fruit, pulp and peel) were analysed by using the HPLC method. Total phenolic content and antioxidant capacity of samples was also found in 25.00-11.63 mg GAE/g DW and 49.86-86.12 µmol TE/g DW. The highest antioxidant activity was identified in the peel of the Kara Sakı apple whereas the lowest was identified in the pulp of Ak Sakı. Varieties of apple differ significantly in terms of ferulic acid and hidroxycinnamic acid. (-)-Epicatechin was found in the peel of Kara Sakı apple at the very most and p- coumaric acid was found in the pulp of Kara Sakı at the very least. Hidroxycinnamic acid was identified only in the peel. It is approved to these cultivars show unique long shelf life (unusual for apples) without any storage condition due to the significantly presence of ferulic acid.
Show more [+] Less [-]Evaluation of Microbiological, Physicochemical and Sensorial Properties of Purple Basil Kombucha Beverage
2019
Seydi Yıkmış | Sergen Tuğgüm
Kombucha is a beverage prepared from fermented traditionally-flavored black or green tea (Camellia sinensis L.) with symbiotic culture of bacteria and yeast (SCOBY). In this study, the changes in the physicochemical, bioactive components, microbial quality and sensory properties of black tea kombucha and different proportions of purple basil (Ocimum basilicum L.) kombucha after fermentation were evaluated. While the pH values decreased during storage, the total acidity value increased. Purple basil had higher total phenolic content at all storage times than the other samples. At the end of the study, it was concluded that the total amount of phenolic compounds and flavonoids in purple basil was highly conserved compared to the other samples. Antioxidant values on the 30th day determined highest DPPH (radical scavenging activity) (64.19%) and CUPCAC (cupric reducing antioxidant capacity) (41.48%) in the purple basil kombucha beverage. When the color values were examined, it was found that there were statistically significant differences in the overall storage process in all samples. There was no significant change inconsistency, smell, taste and general acceptance with the storage process. As a result, 30-day storage period was found to be more successful and favorable for 100% purple basil kombucha tea.
Show more [+] Less [-]Properties of Antioxidant and Anti-Inflammatory Activity and Phenolic Profiles of Şevketi Bostan (Cnicus benedictus L.) Cultivated in Aegean Region from Turkey
2017
Zehra Can | Nimet Baltaş | Saban Keskin | Oktay Yıldız | Sevgi Kolaylı
The aim of this work was to evaluate the phenolic profiles and anti-inflammatory, antioxidant and gastro-protective activities of Cnicus benedictus L., a type of milk thistle cultivated in Turkey. The total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP) and the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity was measured to determine antioxidant capacity. The anti-urease and anti-xanthine oxidase activities were used to determine the gastro-protective and anti-inflammatory potential of the plant extracts, respectively. The TPC was 337.40 and 635.10 mg of gallic acid equivalents (GAE)/100 g and TFC was 41.05 -119.12 mg of quercetin equivalents (QE)/100 g in the root and leaf extracts, respectively. The root and leaf extracts of Cnicus benedictus L., were exhibited different inhibition values against both of the enzymes. The inhibition effect of the both enzymes were calculated as IC50 (mg/mL) in terms of 50% inhibition of the enzymes. The xanthine oxidase activity of the leaf and root was 18.53 and 19.75 mg/mL and the urease activity were 2.29 mg/mL and 11.53 mg/mL, respectively. Fifteen phenolic compounds were determined by high-performance liquid chromatography (HPLC-UV). Vanillic, silibinin B, ferulic acid and rutin were found major amount of the plant. In conclusion, the plant have high potential beneficial nutraceuticals and consumption of the together with its roots and leafs will be beneficial in terms of nutrition.
Show more [+] Less [-]UV-B Radiations and Secondary Metabolites
2020
İlkay Yavaş | Aydın Ünay | Shafaqat Ali | Zohaib Abbas
Ultraviolet-B (UV-B: 280 to 320 nm) radiations have appeared to be detrimental to plants, due to their damaging effects on proteins, lipids, membranes and DNA. UV-B radiations are a significant regulator of plants’ secondary metabolites. High intensity of ultraviolet radiations may interfere with growth and productivity of crops. But low levels of UV-B radiations give rise to changes in the plants’ secondary metabolites such as phenolic compounds, carotenoids and glucoseinolates. Therefore, low intensity of UV-B radiations may be used to generate plants, enriched with secondary metabolites, having improved reproductive ability, early ripening and tolerance against fungi, bacteria and herbivores.
Show more [+] Less [-]The Effects of Seed Infestation by Fusarium proliferatum on Root and Crown Rot, Plant Growth and Phenolic Compounds in Roots of Some Pumpkin (Cucurbita pepo L.) Cultivars
2023
Ebru Sevinç | Nuray Özer
This study investigates the reactions of four summer pumpkin cultivars (cvs. Çağlayan, Mert Bey, Sena Hanım, TG38) to root and crown rot caused by Fusarium proliferatum by taking into account criteria such as disease severity, plant growth (number of leaves, height, dry and fresh weight of shoot) and the accumulation of phenolic compounds in the roots. Seeds of each cultivar were inoculated with the pathogen and left to develop for 1 month at 25oC in a controlled climate room. The content of phenolic compounds in ethanolic root extracts was determined using high-performance liquid chromatography (HPLC). Cv. Sena Hanım had the lowest disease severity (4.40%) among the cultivars, followed by cvs. Çağlayan (10.62%) and Mert Bey (11.07%). Plants developed from inoculated seeds of cvs. Çağlayan and Sena Hanım had no decrease in the number of leaves and in length, fresh and dry weight of shoots in comparison to the control (plants from non-inoculated seeds), while cv. Mert Bey demonstrated a decrease at very low rates in shoot fresh and dry weight (2.24% and 0.77%, respectively). The phenolic compound that exhibited the highest increase in root extracts of cv. Sena Hanım compared to the control among the cultivars was p-coumaric acid (6.57-fold). This study demonstrates that p-coumaric acid can play an important role in the resistance of pumpkin to seed infestation by F. proliferatum.
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