Ferrous Ion Chelating Assay Research Articles

Polyphenol Compositions and Antioxidant Activity of Non-centrifugal Sugars Prepared by Ceramic Membrane Filtration Process

The polyphenol contents and ingredients of non-centrifugal sugars (NCS) obtained from juices clarified with ceramic membrane were measured and their antioxidant activities were investigated via 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, 2,2ʹ-azinobis (3-ethylbenzothiazoline-6-sulfonic acid assay (ABTS), and ferrous and cupric ion chelating assays. According to this research, the results showed that there were significant differences in the six NCSs, the contents of total phenolics and flavonoids were in range of 2846.21~4073.48 and 1999.24~2438.63 µg/g respectively and during the results of high performance liquid chromatography (HPLC), gallic acid showed the highest value. As for the antioxidant effect, DPPH, ABTS and cupric ion chelating showed better effects than control experiments, which suggested NCS had a decent antioxidant effect. In these results, D(GUC23-2) showed the best effects in the experiments of DPPH, ABTS and ferrous ion chelating. Combined with the correlation analysis, it was found that polyphenol had a high correlation with the antioxidant activity. Therefore, it could preliminarily consider that the structure and content of polyphenols had an important effect on the antioxidant activity of NCS. In summary, the sugarcane varities affect the contents of NCS and the antioxidant effect, and this study would provide some theoretical basis for the screening of sugar cane special type of sugar cane and the further study of cultivation.The difference of sugarcane varieties was the main factor that caused the difference of the kinds and contents of brown sugar polyphenols, and the difference of polyphenols content and composition was the main reason for the difference of antioxidant activity of different varieties of brown sugar.

Determination of the Chemical Composition, Antioxidant, and Enzyme Inhibitory Activity of Onosma mollis DC

Onosma species have long been used traditionally for respiratory tract infections, abdominal pain, wound treatment, burns, and constipation. This study aims to investigate the chemical composition and in vitro antioxidant and enzyme inhibitory activities of ethyl acetate (EtOAc), methanol (MeOH), and water extracts of Onosma mollis DC. MeOH extract was richer in both phenolics and flavonoids than other extracts (44.06 mg GAEs/g and 41.57 mg QEs/g, respectively). The findings obtained from the results of the chromatographic analysis also supported the results of the spectrophotometric analysis. The MeOH extract was the richest in terms of most of the phytochemicals screened. Apigenin 7-glucoside, luteolin 7-glucoside, rosmarinic acid, vanillic acid, and pinoresinol were over 1000.0 μg/g in MeOH extract. The extract in question showed the highest activity in phosphomolybdenum, DPPH, and ABTS radical scavenging and CUPRAC and FRAP reducing power activity assays (2.01, 3.33, 2.30, 1.48, and 0.79 mg/ml, respectively). The water extract presented the highest activity in the ferrous ion chelating assay (1.01 mg/ml). While EtOAc extract showed high activity in acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase inhibitory activity tests (1.11, 1.49, and 1.07 mg/ml, respectively), MeOH extract showed significant efficacy in tyrosinase and α-amylase inhibitory activity assays (2.94 and 2.08 mg/ml, respectively). There was a high correlation between the total phenolics/flavonoids of the extracts and their antioxidant activities (correlation coefficients were over 0.9). In addition, the phytochemicals mentioned above were found to contribute significantly to the antioxidant activity. It was concluded that a more detailed analysis should be done to determine the compounds responsible for the enzyme inhibitory activities of the extracts.

Sagan Dalya Tea, a New "Old" Probable Adaptogenic Drug: Metabolic Characterization and Bioactivity Potentials of Rhododendron adamsii Leaves.

Adams’ rhododendron (Rhododendron adamsii Rehder) or Sagan Dalya tea is a famous Siberian evergreen medical plant of the Ericaceae family used in traditional medicines of Buryats, Yakuts, and Mongols as a tonic, stimulant, and adaptogenic drug. The high popularity of R. adamsii coupled with poor scientific knowledge prompted the addressing of gaps related to metabolic and biomedical data of Sagan Dalya tea. The application of solid-phase extraction and liquid chromatography-mass spectrometric techniques for the metabolomic study of R. adamsii leaf extracts resulted in the identification of more than 170 compounds, including carbohydrates, organic acids, simple phenol glycosides, triterpene glycosides, flavonoids, prenylated phenols, benzoic acid derivatives, hydroxycinnamates, dihydrochalcones, catechins, and procyanidins, most of which were identified for the first time in the plant. Extended surveys of the seasonal content of all detected compounds prove that specific metabolite variations reflect the bioactivity of R. adamsii extracts. Regarding in vitro methods, the expressed antioxidant potential of R. adamsii extracts was investigated via radical-scavenging, nitric oxide scavenging, and ferrous (II) ion chelating assays. The animal-based swimming to exhaustion test demonstrates the stimulating influence of R. adamsii extract on physical performance and endurance, concluding that the drug could act as an adaptogen. Thus, Sagan Dalya tea (R. adamsii) has confirmed its “old” application as a tonic remedy and requires further precise study as a novel adaptogenic plant.

Chemical Composition, Antioxidant and Enzyme Inhibitory Activities of Onosma bourgaei and Onosma trachytricha and in Silico Molecular Docking Analysis of Dominant Compounds.

The aim of this study was to investigate the chemical composition, antioxidant and enzyme inhibitory activities of methanol (MeOH) extracts from Onosma bourgaei (Boiss.) and O. trachytricha (Boiss.). In addition, the interactions between phytochemicals found in extracts in high amounts and the target enzymes in question were revealed at the molecular scale by performing in silico molecular docking simulations. While the total amount of flavonoid compounds was higher in O. bourgaei, O. trachytricha was richer in phenolics. Chromatographic analysis showed that the major compounds of the extracts were luteolin 7-glucoside, apigenin 7-glucoside and rosmarinic acid. With the exception of the ferrous ion chelating assay, O. trachytricha exhibited higher antioxidant activity than O. bourgaei. O. bourgaei exhibited also slightly higher activity on digestive enzymes. The inhibitory activities of the Onosma species on tyrosinase were almost equal. In addition, the inhibitory activities of the extracts on acetylcholinesterase (AChE) were stronger than the activity on butyrylcholinesterase (BChE). Molecular docking simulations revealed that luteolin 7-glucoside and apigenin 7-glucoside have particularly strong binding affinities against ChEs, tyrosinase, α-amylase and α-glucosidase when compared with co-crystallized inhibitors. Therefore, it was concluded that the compounds in question could act as effective inhibitors on cholinesterases, tyrosinase and digestive enzymes.

Antioxidant, cytotoxicity, and anti-human lung cancer properties of Linum usitatissimum seed aqueous extract in in vitro conditions: a pre-clinical trial study

IntroductionLinum usitatissimum seed or flax seed is known as a potential candidate as a remedy to treat various diseases in many traditional medicines around the world. In the current study, the antioxidant, cytotoxicity, and anti-human lung cancer properties of Linum usitatissimum seed were investigated in in vitro conditions.Material and methodsAntioxidant activity of the plant was analyzed using radical scavenging activity and ferrous ion chelating assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to evaluate anti-lung cancer properties of the plant.ResultsThe plant extract scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) as a free radical with an IC50 of 34.2 ±0.9 µg/ml. The plant was also found to be rich in phenolic compounds with 294.8 ±2.3 mg GAE/g for total phenolic content. Cell viability of Linum usitatissimum seed was very low against lung poorly differentiated adenocarcinoma (PC-14), lung moderately differentiated adenocarcinoma (LC-2/ad), and lung well-differentiated bronchogenic adenocarcinoma (HLC-1) cell lines without any cytotoxicity towards the normal cell line. The best anti-human lung cancer properties of Linum usitatissimum seed against the above cell lines were observed in the case of the PC-14 cell line. According to the above findings, Linum usitatissimum seed may be administered for the treatment of several types of human lung cancer in humans. According to the results, the IC50 values of plant extract against lung poorly differentiated adenocarcinoma (PC-14), lung moderately differentiated adenocarcinoma (LC-2/ad), and lung well-differentiated bronchogenic adenocarcinoma (HLC-1) cell lines were found to be 392, 483, and 564 µg/ml, respectively.ConclusionsIt appears the recent formulation can be used as a novel chemotherapeutic supplement in humans.

Onosma gracilis (Trautv.) and O. oreodoxa (Boiss. & Heldr.): Phytochemistry, in silico docking, antioxidant and enzyme inhibitory activities

In this study, it was aimed to determine the in vitro antioxidant and enzyme inhibitory activities of methanol (MeOH) extracts isolated from Onosma gracilis (Trautv.) and O. oreodoxa (Boiss. & Heldr.). O. oreodoxa was found to be richer in both phenolics and flavonoids than O. gracilis. The amounts of total phenolics and flavonoids in O. oreodoxa were 53.76 mg GAEs/g and 25.29 mg QEs/g, respectively. In addition to spectrophometric analysis, in chromatographic analyzes, twenty-four and twenty-six compounds were identified in O. gracilis and O. oreodoxa, respectively. High amounts of hesperidin (6647.2 and 5260.75 µg/g extract, respectively), hyperoside (7153.26 and 10216.74 µg/g extract, respectively) and rosmarinic acid (21824.33 and 87493.19 µg/g extract, respectively) were found in O. gracilis and O. oreodoxa. While O. oreodoxa showed higher activity in cupric reducing antioxidant power (CUPRAC), ferric reducing antioxidant power (FRAP), phosphomolybdenum, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, and ferrous ion chelating assays (324.22, 175.41, 719.50, 125.60 mg TEs/g extract and 25.11 mg EDTAEs/g extract, respectively), ABTS radical scavenging activity of O. gracilis (164.55 mg TEs/g extract) was higher than that of O. oreodoxa. O. gracilis also exhibited higher inhibitory activity on acetylcholinesterase (AChE), butyrylcholinesterase (BChE) (2.57 mg GALAEs/g extract) and α-glucosidase (1674.24 mg ACEs/g extract). On the other hand, the sample showing the most effective inhibition on α-amylase and tyrosinase was O. oreodoxa (417.34 mg ACEs/g extract and 136.18 mg KAEs/g extract, respectively). As a result of the molecular docking analysis performed to determine the contribution of hesperidin, hyperoside and rosmarinic acid to the enzyme inhibitory activity, the binding affinity and inhibition constant of hyperoside to all enzymes were quite high and therefore it was concluded that it may be the compound that contribute to the activity.

Phenolic composition and biological activities of Turkish endemic plant: Stachys cretica subsp. kutahyensis

Stachys cretica L. subsp. kutahyensis is a Turkish endemic plant specie and used in flock medicine against many diseases. To our knowledge, no data are available on the chemical composition and the biological activities of this plant. In this study, the phytochemical composition, the enzyme inhibition and antioxidant activity of this specie were assessed. The Liquid chromatography-electrospray ionization-tandem mass spectrometry (LC–ESI–MS) analysis allowed the determination of 26 phenolic compounds with predominance of chlorogenic acid and verbascoside. The concentration of phenolic acids and flavonoid compounds significantly changed according to solvent used (water and methanol). From five different methods used, the antioxidant activity was important and significantly different between extracts for ferrous ion chelating and ABTS assays where the aqueous extract expressed higher antioxidant activity. However, interesting enzyme inhibition activities were observed for the extracts of S. cretica subsp. kutahyensis using α-amylase and tyrosinase. The highest α-amylase and tyrosinase inhibition activities were recorded with the methanol extract. The results confirm that S. cretica subsp. kutahyensis could be used as valuable new natural source with beneficial biological properties for food and pharmacology applications.

Synthesis, Characterization and antioxidant activities of Semicarbazide and Thiosemicarbazide Derivatives

In this research work Semicarbazide, thiosemicarbazide derivatives 3 to 25 were synthesized by conventional methods with high percentage yield and reaction rate. 1H-NMR and EIMS spectroscopic techniques were used to elucidate the structure of the synthesized compounds. The effect of thiosemicarbazide and semicarbazide derivatives as an antioxidant agents were studied by DPPH free radical scavenging, ferric ion reducing, ferrous ion chelating assays. Higher DDPH radical scavenging activity exhibited by most of the compounds as compared to standard vitamin C. Excellent ferric ion reducing activity was indicated by compounds of theseriesas compared to standard vitamin C. However most of the compounds generally showed average ferrous ion chelating activity than standard EDTA.

Synthesis, Characterization and antioxidant activities of Semicarbazide and Thiosemicarbazide Derivatives

In this research work Semicarbazide, thiosemicarbazide derivatives 3 to 25 were synthesized by conventional methods with high percentage yield and reaction rate. 1H-NMR and EIMS spectroscopic techniques were used to elucidate the structure of the synthesized compounds. The effect of thiosemicarbazide and semicarbazide derivatives as an antioxidant agents were studied by DPPH free radical scavenging, ferric ion reducing, ferrous ion chelating assays. Higher DDPH radical scavenging activity exhibited by most of the compounds as compared to standard vitamin C. Excellent ferric ion reducing activity was indicated by compounds of theseriesas compared to standard vitamin C. However most of the compounds generally showed average ferrous ion chelating activity than standard EDTA.

Antioxidant Activity-guided Phytochemical Investigation of Artemisia aucheri Boiss.: Isolation of Ethyl Caffeate and a Spinacetin Glycoside.

Antioxidant activity of five different extracts (petroleum ether, dichloromethane, ethyl acetate, ethanol and ethanol-water) of Artemisia aucheri aerial parts was investigated by three various methods: ferrous ion chelating (FIC) assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and β-carotene bleaching (BCB) test. Total phenolic contents (TPC) were measured by Folin–Ciocalteu method. The hydroethanolic extract exhibited the stronger inhibitory activity in BCB and FIC assays than the other extracts. Among the extracts analyzed, the ethyl acetate and ethanolic extracts exhibited the highest TPC and DPPH radical scavenging activity, respectively. Reversed phase vacuum liquid chromatography of ethanolic extract (with the highest extraction yield) produced five fractions (A to E) which were subjected to all antecedent experiments. The same sample (Fraction C) showed the highest TPC and DPPH radical scavenging activity while there were no statistically significant correlations between TPC and EC50 values of various antioxidant assays. Ethyl caffeate and a spinacetin glycoside were isolated from the most active fraction and their structures were established using spectroscopic analysis including NMR and MS.

Furoate Based Functionalised Ionic Liquid: Antimicrobial and Antioxidant Studies

A tetraalkyl ammonium cation and furoate anion based functionalised ionic liquid (FIL), N-methyl-N,N,N-trioctylammonium furoate ([MTOA]+[FA]–) has been synthesised and characterised using FT-IR, NMR, and UV spectroscopic techniques. The invitro antimicrobial activity of the synthesised FIL against two types of Gram-positive bacteria, namely Staphylococcus aureus and Enterobacter faecalis as well as Gram-negative bacteria, namely Escherichia coli and Pseudomonas aeruginosa was tested using a well diffusion method. Similarly, an antifungal test was done against Candida albicans. [MTOA]+[FA]– showed significant inhibitory effect against all the organisms tested as compared with the chosen standards. Antibacterial activity against gram-positive bacteria (zone of inhibition: 16 to 30mm) was found to be higher than that of Gram-negative bacteria (zone of inhibition: 11 to 19mm). Moreover, the antioxidant activity of the synthesised FIL from a ferrous ion (Fe2+) chelating assay and its scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, H2O2, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical using spectrophotometric methods are reported. The FIL, [MTOA]+[FA]– showed a moderate antioxidant activity.

Antioxidant Potential of Mung Bean (Vigna radiata) Albumin Peptides Produced by Enzymatic Hydrolysis Analyzed by Biochemical and In Silico Methods.

The objective of this study was to investigate the biochemical antioxidant potential of peptides derived from enzymatically hydrolyzed mung bean (Vigna radiata) albumins using an 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay, a ferrous ion chelating assay and an oxygen radical absorbance capacity (ORAC) assay. Peeled raw mung bean was ground into flour and mixed with buffer (pH 8.3, 1:20 w/v ratio) before being stirred, then filtered using 3 kDa and 30 kDa molecular weight cut-off (MWCO) centrifugal filters to obtain albumin fraction. The albumin fraction then underwent enzymatic hydrolysis using either gastrointestinal enzymes (pepsin and pancreatin) or thermolysin. Peptides in the hydrolysates were sequenced. The peptides showed low ABTS radical-scavenging activity (90–100 μg ascorbic acid equivalent/mL) but high ferrous ion chelating activity (1400–1500 μg EDTA equivalent/mL) and ORAC values (>120 μM Trolox equivalent). The ferrous ion chelating activity was enzyme- and hydrolysis time-dependent. For thermolysin hydrolysis, there was a drastic increase in ferrous ion chelating activity from t = 0 (886.9 μg EDTA equivalent/mL) to t = 5 min (1559.1 μg EDTA equivalent/mL) before plateauing. For pepsin–pancreatin hydrolysis, there was a drastic decrease from t = 0 (878.3 μg EDTA equivalent/mL) to t = 15 (138.0 μg EDTA equivalent/mL) after pepsin was added, but this increased from t = 0 (131.1 μg EDTA equivalent/mL) to t = 15 (1439.2 μg EDTA equivalent/mL) after pancreatin was added. There was no significant change in ABTS radical scavenging activity or ORAC values throughout different hydrolysis times for either the thermolysin or pepsin–pancreatin hydrolysis. Overall, mung bean hydrolysates produced peptides with high potential antioxidant capacity, being particularly effective ferrous ion chelators. Other antioxidant assays that use cellular lines should be performed to measure antioxidant capacity before animal and human studies.

Two endemic Onosma species (O. sieheana and O. stenoloba): A comparative study including docking data on biological activity and phenolic composition

There are convincing evidences that species belonging to the Onosma genus have been used in the treatment of various diseases for centuries. In this study, antioxidant and tyrosinase and α-amylase inhibitory activities of the methanol (MeOH) extracts of two endemic Onosma species (O. sieheana Hayek and O. stenoloba Hausskn. ex Riedl), which are endemic to the flora of Turkey, were compared. Phosphomolybdenum, reducing power [Cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP)], radical scavenging [on '2,2-diphenyl-1-picrylhydrazyl' (DPPH) and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS)] and ferrous ion chelating assays were used to determine the antioxidant activities of the extracts. All test systems except for the ferrous ion chelating assay resulted in O. sieheana's superiority. The antioxidant activity of O. sieheana in the test systems mentioned above was found to be 2.11, 1.57, 1.01, 3.54 and 3.19 mg/mL, respectively. However, in ferrous ion chelating activity assay, O. stenoloba showed higher activity with an IC50 value of 2.98 mg/mL. In the tyrosinase inhibitor activity test, O. stenoloba extract showed higher activity (1.89 mg/mL), while in the α-amylase inhibitory activity assay, O. sieheana was found to be more effective (3.02 mg/mL). As a result of total phenolic and flavonoid compound analysis, O. sieheana was found to be richer than the other in terms of both groups. LC–ESI–MS/MS analysis revealed that rosmarinic acid, apigenin 7-glucoside, luteolin 7-glucoside, chlorogenic acid, hesperidin, pinoresinol, hyperoside and 4-hydroxybenzoic are the main compounds of the extracts. According to the results of docking analysis performed to reveal the interactions of the main components with tyrosinase, it is thought that pinoresinol, hesperidin, luteolin 7-glucoside, apigenin 7-glucoside, and hyperoside may be phytochemicals responsible for the inhibitory activity. Additionally, the binding energies of pinorecinol, apigenin 7-glucoside, luteolin 7-glucoside, hyperoside, chlorogenic acid, and rosmarinic acid to α-amylase were found to be quite high.

Onosma aucheriana, O. frutescens, and O. sericea: Phytochemical profiling and biological activity

It is known that Onosma species are frequently used in the treatment of various ailments such as bronchitis, strangury, leucoderma, abdominal pain and fever. The aim of this study was to investigate the antioxidant, tyrosinase and α-amylase inhibitory activities of the MeOH extracts obtained from the aerial parts of Onosma aucheriana DC., O. frutescens Lam., and O. sericea Willd. Total phenolic/flavonoid and liquid chromatography electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) analyzes were also performed to determine the chemical composition of the extracts. In antioxidant activity tests, except for ferrous ion chelating, the activity of O. frutescens was found to be significantly higher than the others. The antioxidant activity of this species in 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), and phosphomolybdenum tests were found to be 1.14, 1.04, 0.53, 0.35 and 1.18 mg/mL, respectively. The ferrous ion chelating assays resulted in the superiority of O. aucheriana [the half maximal inhibitory concentration (IC50): 2.57 mg/mL]. In tyrosinase and α-amylase inhibitory activity tests, it was found that the activity potentials of O. aucheriana and O. sericea extracts were quite close to each other. Tyrosinase and α-amylase inhibitory activity of O. aucheriana were determined as 2.19 and 2.51 mg/mL. Additionally, the IC50 values of O. sericea on the same enzymes were measured as 2.28 and 2.50 mg/mL. As a result of the spectrophotometric analysis, when compared with the others, it was understood that O. frutescens and O. sericea extracts were richer in phenolics and flavonoids, respectively. Chromatographic analyzes have shown that the extracts contain high amounts of rosmarinic acid, apigenin 7-glucoside, luteolin 7-glucoside, hesperidin, hyperoside, ferulic acid, vanillic acid, caffeic acid and 4-hydroxybenzoic acid.

Anthemis chia: Biological capacity and phytochemistry

Anthemis species are also of great importance in the cosmetics and pharmaceutical industries. In this study, phytochemical compositions, antioxidant and enzyme inhibitory activities of ethyl acetate (EtOAc), methanol (MeOH) and water extracts obtained from Anthemis chia L. flowers were investigated. The total phenolic and flavonoid compound analysis revealed that the richest one in terms of these compounds was the MeOH extract [65.22 mg gallic acid equivalents (GAEs)/g extract and 73.32 mg quercetin equivalents (QEs)/g extract, respectively]. As a result of liquid chromatography electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) analysis, it was determined that the main components of the extracts were chlorogenic acid, protocatechuic acid, hyperoside, caffeic acid, apigenin 7-glucoside and luteolin 7-glucoside. Except for the ferrous ion chelating assay, all other antioxidant activity tests resulted in the superiority of the MeOH extract. As a result of the relative antioxidant capacity index (RACI) analysis (including total phenolic and flavonoid compound contents) performed in order to compare the data obtained from antioxidant activity tests, it was confirmed that the antioxidant activity potential of MeOH extract was higher than other extracts. The activity values of this extract in the phosphomolybdenum, cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were determined to be 350.36, 655.18, 435.78, 265.33 and 325.25 mg trolox equivalents (TEs)/g extract, respectively. In addition to the total phenolic and flavonoid contents of the extracts, chlorogenic acid, caffeic acid, hyperoside and apigenin 7-glucoside are also thought to contribute to antioxidant activity. MeOH extract also exhibited the highest activity in α-amylase and tyrosinase inhibitory activity tests. α-Amylase and tyrosinase inhibitor activity of the MeOH extract was measured as 413.66 mg acarbose equivalents (ACEs)/g extract and 290.22 mg kojic acid equivalents (KAEs)/g extract, respectively. Flavonoids seem to contribute more to enzyme inhibitory activity than phenolics. However, caffeic acid is also thought to contribute significantly to the tyrosinase inhibitory activity. As a result, it was concluded that A. chia flowers could be used as an alternative antioxidant, skin whitening and anti-diabetic agent in the food, cosmetic and medical industries.

Astragalus gymnolobus, A. leporinus var. hirsutus, and A. onobrychis: Phytochemical analysis and biological activity

Astragalus is a genus with many important medicinal plant species. The historical background of Astragalus species dates back to 2000–3000 years. In this study, it was aimed to investigate the phytochemical composition, antioxidant, tyrosinase and α-amylase inhibitory activities of the MeOH (methanol) extracts obtained from three different Astragalus species (A. gymnolobus Fisch., A. leporinus Boiss. var. hirsutus (Post) D.F. Chamb., and A. onobrychis L.). It was understood that A. gymnolobus and A. onobrychis extracts are richer than A. leporinus var. hirsutusin terms of phenolics and flavonoids. According to the results of Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC–ESI–MS/MS) analysis, it was determined that hesperidin and hyperoside were found in high amounts in the extracts. A strong correlation was found between the phytochemical compositions of the plants and their antioxidant activities. The order of the antioxidant activity of A. gymnolobus from strongest to the weakest was as follows: Ferric Reducing Ability of Plasma (FRAP) (1.13 mg/mL), ferrous ion chelating (1.53 mg/mL), Cupric Reducing Antioxidant Capacity (CUPRAC) (1.58 mg/mL), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) (2.52 mg/mL), phosphomolybdenum (2.91 mg/mL), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) (3.86 mg/mL). In the case of A. onobrychis, the order of the antioxidant activity was found to be: FRAP (1.25 mg/mL), ferrous ion chelating assays (1.69 mg/mL), CUPRAC (1.93 mg/mL), ABTS (2.21 mg/mL), phosphomolybdenum (2.77 mg/mL), and DPPH (4.50 mg/mL). A. gymnolobus (1.27 mg/mL, 281.92 mg KAEs/g extract) and A. onobrychis (1.25 mg/mL, 287.89 mg KAEs/g extract) have also been found to be effective tyrosinase inhibitors. In α-amylase inhibitory activity test, A. leporinus var. hirsutus was found to show the highest activity (4.06 mg/mL, 298.54 mg ACEs/g extract). According to Pearson correlation test results, it was concluded that hesperidin significantly contributed to the biological activities of the extracts.

Novel insights into the fruit and seed extracts of Morinda morindoides (Baker) Milne-Redh: HPLC-ESI-Q-TOF-MS profiling, antioxidant, and enzyme inhibitory propensities.

In this study, we attempted for the first time to determine the phytochemical compositions and biopharmaceutical properties of the methanolic and aqueous extracts of Morinda morindoides fruits and seeds. Antioxidant propensities of the extracts were determined via free radical-scavenging, phosphomolybdenum, metal chelating, and reducing power assays. Inhibitory activities against cholinesterases (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)), tyrosinase, α-amylase, and α-glucosidase were assessed. Moreover, the total phenolic and flavonoid contents were determined. High Performance Liquid Chromatography coupled to Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry (HPLC-ESI-Q-TOF-MS) analysis was performed to establish the chemical profile of the investigated extracts. The tested extracts showed remarkable antioxidant abilities with aqueous fruit extract being most potent in all assays, except for ferrous ion chelating assay. Overall, the methanolic extracts were potent inhibitors of the tested enzymes. In conclusion, M. morindoides may be endorsed as promising sources of bioactive compounds and used for designing functional foods. PRACTICAL APPLICATIONS: In recent years, new compounds from plant sources have attracted great interest to design functional foods. Thus, we aimed to detect biological and chemical properties of Morinda morindoides fruits and seeds, a widely used as food with medicinal properties in Africa. Based on our findings, fruits extracts exhibited stronger activity when compared to seed extracts. Also, chemical identification was performed for each extracts. The presented findings could provide valuable information into the pool of scientific knowledge and may be basis for the design of novel functional applications from M. morindoides.

Untargeted metabolomic profiling of three Crataegus species (hawthorn) and their in vitro biological activities.

In this investigation, the chemical and biological profiles of three Turkish Crataegus species (Crataegus orientalis, Crataegus szovitsii and Crataegus tanacetifolia) were studied in order to provide the first comprehensive characterization and their health-promoting potential. In this respect, polyphenolic profiles were evaluated using ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The in vitro antioxidant activities of the Crataegus samples were evaluated by using free-radical scavenging, phosphomolybdenum, ferrous-ion chelating, and reducing power assays. The inhibitory activities against α-glucosidase, amylase, cholinesterases (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)), and tyrosinase were also established. The untargeted metabolomic approach highlighted the effect of both extraction types and species on the phenolic profiles of different Crateagus tissues (i.e. leaves and twigs). The methanolic extracts showed the maximum radical scavenging and reducing activity in all test systems, whereas for ferrous-ion chelating assays the decocted and infused extracts showed the highest activity. Only the methanolic extracts were effective against AChE and BChE. The extract tested showed remarkable inhibitory effects against tyrosinase and α-glucosidase, whereas all the extracts exhibited modest inhibition against α-amylase. Overall, the twig extracts of the three species studied showed superior antioxidant and enzyme inhibitory activities. On the basis of these results, the three Crataegus species can be classified as potent bioresources for high-value phytochemicals, which warrant further investigations for developing novel nutraceuticals. © 2019 Society of Chemical Industry.

Phytochemical Screening and in vitro Antioxidant Evaluation of Ajuga iva

Oxidative stress was associated with several diseases. Many epidemiologic studies showed that antioxidant supplementation decreases the state of oxidative stress. The present work aims to study the in vitro antioxidant activity of different parts of Ajuga iva aqueous extract (AIE) simultaneously with a phytochemically analyze. The antioxidant activities of AIE were evaluated in terms of total antioxidant capacity evaluated by the phosphomolybdenum essay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical method, as well as the ferric ion reducing power (FRP) and ferrous ion chelating (FIC) assays. All extracts showed a potent antioxidant activity and a powerful scavenging capacity in comparison with the ascorbic acid (AA) used as reference molecule. Importantly, Ajuga iva leaves exhibited the highest activity in comparison with stems and roots.

Isolation of Two Isochlorogenic Acid Isomers from Phenolic Rich Fraction of Artemisia turanica Krasch.

Total phenolic content (TPC) and antioxidant capacity of five different extracts (petroleum ether (40-60), dichloromethane, ethyl acetate, ethanol and ethanol-water (1:1 v/v)) of Artemisia turanica (A. turanica) aerial parts were determined and phytochemical study on the most promising extract was carried out. Folin–Ciocalteu method, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test, β-carotene bleaching (BCB) method, and ferrous ion chelating (FIC) assay were performed. Vacuum liquid chromatography (VLC) and semi-preparative HPLC were used for bioassay-guided phytochemical isolation. Structures of isolated compounds were established using spectroscopic analysis including NMR and MS. Among all the extracts analyzed, the hydroethanolic extract exhibited the highest phenolic content and antioxidant activity. VLC of this extract yielded seven fractions (A to G) which were subjected to all antecedent experiments. The same sample (Fraction D) showed the highest total phenolic content and free radical scavenging activity but the only statistically significant correlation between TPC and EC50 values was observed for BCB. 3,5-dicaffeoylquinic acid (isochlorogenic acid A), and 4,5-dicaffeoylquinic acid (isochlorogenic acid C) was isolated from the most active fraction. Antioxidant activity of A. turanica is probably partly due to the presence of isomers of isochlorogenic acid.