Metal Chelating Activity Research Articles

Fishing antioxidant 4-hydroxycoumarin derivatives: synthesis, characterization, and in vitro assessments.

Coumarins represent a diverse class of natural compounds whose importance in pharmaceutical and agri-food sectors has motivated multiple novel synthetic derivatives with broad applicability. The phenolic moiety in 4-hydroxycoumarins underscores their potential to modulate the equilibrium between free radicals and antioxidant species within biological systems. The aim of this work was to assess the antioxidant activity of 18 4-hydroxycoumarin coumarin derivatives, six of which are commercially available and the other 12 were synthesized and chemically characterized and described herein. The 4-hydroxycoumarins were prepared by a two steps synthetic strategy with satisfactory yields. Their antioxidant potential was evaluated through three in vitro methods, two free radical-scavenging assays (DPPH• and ABTS•+) and a metal chelating activity assay. Six synthetic coumarins (4a, 4g, 4h, 4i, 4k, 4l) had a scavenging capacity of DPPH• higher than butylated hydroxytoluene (BHT) (IC50=0.58mmol/L) and compound 4a (4-hydroxy-6-methoxy-2H-chromen-2-one) with an IC50=0.05mmol/L outperformed both BHT and ascorbic acid (IC50=0.06mmol/L). Nine hydroxycoumarins had a scavenging capacity against ABTS•+ greater (C3, 4a, 4c) or comparable (C1, C2, C4, C6, 4g, 4l) to Trolox (IC50=34.34µmol/L). Meanwhile, the set had a modest ferrous chelation capacity, but most of them (C2, C5, C6, 4a, 4b, 4h, 4i, 4j, 4k, 4l) reached up to more than 20% chelating ability percentage. Collectively, this research work provides valuable structural insights that may determine the scavenging and metal chelating activity of 4-hydroxycoumarins. Notably, substitutions at the C6 position appeared to enhance scavenging potential, while the introduction of electron-withdrawing groups showed promise in augmenting chelation efficiency.

Urtica pilulifera leaves extract mitigates cadmium induced hepatotoxicity via modulation of antioxidants, inflammatory markers and Nrf-2 signaling in mice.

Introduction: Cadmium (Cd) is a harmful heavy metal that results in many toxic issues. Urtica pilulifera showed potential pharmaceutical applications. This study investigated the possible ameliorative mechanism of Urtica pilulifera leaves extract (UPLE) against hepatotoxicity induced by cadmium chloride (CdCl2) in mice. Methods: In vitro phytochemical screening and the metal-chelating activity of UPLE were ascertained. Four groups of forty male mice were used (n = 10) as follows; Group 1 (G1) was a negative control. G2 was injected i.p., with UPLE (100mg/kg b. wt) daily. G3 was injected i.p., with Cd (5mg/kg b. wt) daily. G4 was injected with Cd as in G3 and with UPLE as in G2. On day 11, the body weight changes were evaluated, blood, and serum samples were collected for hematological and biochemical assessments. Liver tissues were used for biochemical, molecular, and histopathological investigations. Results: The results showed that UPLE contains promising secondary metabolites that considerably lessen the negative effects of Cd on liver. Furthermore, UPLE inhibited oxidative stress and inflammation; restored antioxidant molecules; and promoted nuclear-related factor-2 (Nrf-2) expression. Also, UPLE improved the histopathological alterations induced by Cd. Discussion: This study explored the beneficial role of UPLE treatment in Cd-induced liver injury through enhancing Nrf-2 signaling and antioxidant enzyme gene expression in the liver of mice. Therefore, UPLE could have valuable implications against hepatotoxicity induced by environmental cadmium exposure. Which can be used as a chelating agent against Cd.

Comparative Study on the Effect of Hot Air and Vacuum Drying on Physiochemical Properties and antioxidant Activities of Red Dragon Fruit (Hylocereus polyrhizus) Peel

The red dragon fruit (Hylocereus polyrhizus) peel was subjected to freeze drying (FD), hot air drying (at 50 – 65°C) (HAD), and vacuum drying (at 50 – 65°C) (VD), in which physical properties (color, water activity, water absorption index-WAI, and microstructure), bioactive compounds (ascorbic acid, betacyanin, polyphenol, and flavonoid), and antioxidant activities (DPPH and metal chelating activities) were monitored. The results showed that the lightness (L*) of red dragon fruit peel (RDFP) decreased as HAD and VD were applied especially at higher drying temperatures. Whereas the water absorption index (WAI) of the RDFP was not affected by drying methods. The microstructure surfaces of FD-dried RDFP were smoother than those of samples dried by HAD and VD-dried RDFP. After the drying processes, the bioactive compounds and antioxidative properties of the RDFP powder decreased significantly. However, higher bioactive compounds and antioxidant activities in RDFP dried by VD compared to the samples dried by HAD at the same drying temperatures. The RDFP powder dried by VD at 55°C retaining high physiochemical and antioxidative properties could be utilized as a colorant and nutraceutical ingredient in several food products. Keywords: Red dragon fruit peel, Freeze drying, Vacuum drying, Hot air drying, Bioactive compounds, Antioxidant activity

Antioxidant and antimicrobial activities of mango peel and radish peel-a comparative investigation

The present study investigated the antioxidant and antimicrobial activities of Bao mango and daikon radish peel (Thai variety) ethanolic extracts. The percentage extraction yield of radish peel was higher compared to the mango peel (p < 0.05). However, Mango peel extract (MPE) contained higher total phenolic content (TPC) than radish peel extract (RPE) (p < 0.05). Similar to the TPC value, antioxidant activities including DPPH radical scavenging activity, reducing power, and peroxidation inhibition were higher in the MPE, compared to the RPE, except for metal chelating activity. The antimicrobial analyses suggested that the MPE showed lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values compared to the RPE (p < 0.05) against Gram-positive and Gram-negative bacteria. High-performance liquid chromatography (HPLC) revealed that mangiferin was the major phenolic compound present in MPE, followed by 3, 4 dihydroxybenzoic acid. Therefore, MP could be used as a promising natural antioxidant and antimicrobial agent for food applications.

Synthesis of Spherical Mn2O3 Nanozymes from Different Green Precursors for their Innovative Applications in Catalytic Properties and Bioactivity.

Here, spherical Mn2O3 nanozymes were synthesized via a one-step green method using different green precursors, and their physicochemical properties and biological activities were monitored with various green precursors. Powder X-ray diffraction (PXRD) was performed to determine the crystalline properties and phases involved in the formation of cubic Mn2O3 nanozymes. The synthesized nanozymes were spherical and examined by SEM and FESEM studies. All of the samples synthesized using different green precursors exhibited different sizes but similar spherical shapes. Moreover, all green-synthesized nanozymes catalyzed the oxidation reaction of the chromogenic substrate 3,3'5,5' tetramethylbenzidine (TMB) in the absence of H2O2, and A2 (lemon-mediated Mn2O3 nanozymes), which the followed Michaelis-Menten kinetics, showed the best activity. Therefore, A2 (lemon-mediated nanozyme) showed oxidase-mimicking activity with distinct Km and Vmax values calculated by the Lineweaver-Burk plot. Furthermore, the current nanozymes demonstrated a significant ability to kill both Gram-negative and Gram-positive bacteria as well as effectively destroy biofilms under physiological conditions. Moreover, the green-mediated nanozymes also displayed ROS-scavenging activity. Our nanozymes exhibited scavenging activity toward OH and O2-• radicals and metal chelation activity, which were investigated colorimetrically. Therefore, these nanozymes might be used as effective antibacterial agents and also for the consumption of reactive oxygen species.

Process optimization and identification of antioxidant peptides from enzymatic hydrolysate of bovine bone extract, a potential source in cultured meat

Bone protein is a significant secondary product of the meat industry, comprising a substantial quantity of protein. These proteins could be broken down through enzymatic hydrolysis to generate antioxidant peptides. This study aimed to produce antioxidant peptides from bovine bone extract by enzymatic hydrolysis utilizing Flavourzyme and Protamex by optimizing enzyme amounts and time using the Box–Behnken design. The final optimized conditions obtained through the model were as follows: The amount of Flavourzyme was 1,100 U, the amount of Protamex was 2,814 U, and the time was 3.77 (h). Bovine bone extract hydrolysate (BBEH) was purified stepwise using ultrafiltration membranes with molecular cutoffs of 5, 3, and 1 kDa. To assess the antioxidant capacity of the fractions, several methods were used, including radical scavenging activity “1,1-diphenyl-2-picrylhydrazyl (DPPH),” “2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS),” metal chelating activity (MCA), reducing power (RP), and thiobarbituric acid assay (TBA). The results indicated that the ultrafiltration fraction with a molecular weight of less than 1 kDa showed significant antioxidant activity, with 48, 42, and 50% inhibition rates for DPPH, ABTS, and metal chelating, respectively. Using size exclusion chromatography, the fraction with a molecular weight less than 1 kDa was further separated into five sub-fractions: Frac-I, Frac-II, Frac-III, Frac-IV, and Frac-V. Sub-Frac-III, which exhibits significant DPPH radical scavenging activity (55%) and a reducing power of 0.8 at 700 nm, was separated into six sub-sub-fractions using reversed-phase HPLC (RP-HPLC) based on molecular weight and hydrophobicity. The sub-sub-fraction with the highest value for DPPH radical scavenging activity was sub-Fra-III-6, which exhibited approximately 69.45% activity. The sub-Fra-III-6 was analyzed using LC–MS/MS, which identified two specific peptides: Ala-Pro-Phe with a mass of 333.12 Da and Asp-His-Val with a mass of 369.14 Da. These two peptides are likely the primary peptides that might have a crucial role in antioxidant capacity. It can be concluded that BBEH is a valuable source of natural antioxidants and has the potential to serve as a viable resource in the cultured meat industry.

Phytochemical analyses by LC-HRMS, FTIR spectral analysis, antioxidant, antidiabetic and antityrosinase activity of Crataegus orientalis Pall. ex M. Bieb fruit extracted with various solvents.

Crataegus orientalis Pall. ex M. Bieb fruit (COPMB) is extensively used as a source of various products in the medicinal-aromatic field and holds the potential for erosion control, ornamental purposes, food source, and economic benefits for forest villagers from its fruits. This study aims to determine the chemical components and biological activities of extracts prepared from COPMB using different solvents. The present work was designed to define the antioxidant activity [phosphomolybdenum (total antioxidant capacity), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), cupric ion-reducing antioxidant capacity (CUPRAC) and metal chelating activity (MCA)], phytochemical screening analysis, enzyme inhibitor (α-amylase, α-glucosidase and tyrosinase) potential, and liquid chromatography-high resolution mass spectrometry (LC-HRMS) secondary metabolite profiling in different extracts of COPMB. The results of LC-HRMS revealed that fumaric acid was the main phenolic compound in all extracts. Among the extracts, ethyl acetate extract has the highest phytochemical and antioxidant properties [total phenolic content (TPC): 32.5 mg GAE/g, total flavonoid content (TFC): 12.2 mg QE/g, ABTS: 213.0 mg TE/g; CUPRAC: 126.0 mg TE/g, MCA: 145.0 mg EDTA/g; FRAP: 122.8 mg TE/g; TAC: 2.8 mmol TE/g]. Ethyl acetate and methanol extracts are more effective in α-amylase (0.27 ± 0.01 mg/mL; 0.12 ± 0.00 mg/mL), α-glucosidase (0.63 ± 0.02 mg/mL; 0.77 ± 0.02 mg/mL) and tyrosinase (0.03 ± 0.00 mg/mL; 0.03 ± 0.00 mg/mL) enzyme inhibition potentials compared to standard acarbose (0.75 ± 0.02 mg/mL for α-amylase; 1.11 ± 0.03 mg/mL for α-glucosidase) and kojic acid (0.04 ± 0.00 mg/mL). The findings from this study suggest that COPMB could serve as a valuable source of natural agents for the food and pharmaceutical industry. © 2024 Society of Chemical Industry.

In vitro research to evaluate the antioxidant effects, inhibiting enzymes, methicillin-resistant Staphylococcus aureus strains of Terminalia catappa extracts

AimContribute to the well-being of the Ivorian population through scientific proof of the use of Terminalia cattapa leaves extracts in traditional medicine. MethodologyThe antioxidative effect of aqueous, water-alcoholic, ethyl acetate and hexane derivatives of Terminalia catappa leaves was measured by six tests: DPPH (2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)), FRAP (ferric ion reducing antioxidant power), PPBD (phosphomolybdenum), CUPRAC (cupric ion reducing antioxidant capacity) and MCA (metal chelating activity). The inhibition of the activity of five enzymes (acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase and glucosidase) was also determined. In addition, the broadcast method was used to evaluate impact of the samples on methicillin-resistant Staphylococcus aureus (MRSA) strains. ResultsHighest antioxidant capacity was obtained in the ethanolic sample for DPPH, ABTS, FRAP and PPBD tests. Ethyl acetate sample produced the best CUPRAC and MCA tests. Among inhibitory effect of samples on the five enzymes, aqueous sample showed the strongest anti-acetylCholynesterase and anti-butyrylCholynesterase activity. Best anti-tyrosinase and anti-amylase activity were obtained with the ethanolic sample. Hexane sample obtained the best anti-glucosidase activity while ethanolic and aqueous samples obtained none. All extracts showed no activity on the MRSA strains tested. ConclusionThe chemical compounds present in Terminalia cattapa leaves extracts would not be responsible for the use made in traditional medicine against infections.

Bioactive agents from Parkia biglobosa (Jacq.) R.Br. ex G. Don bark extracts for health promotion and nutraceutical uses.

Parkia biglobosa stem bark extracts were prepared using methanol, methanol 80%, water and ethyl acetate to investigate their phytochemical contents, as well as antioxidant and enzyme inhibitory properties. Liquid chromatography (LC) quadrupole time-of-flight mass spectrometry (MS) and LC-MSn revealed the presence of flavonoids, hydroxycinnamic acid derivatives and gallotannins. Particularly, the water extract contained rutin (480 μg per 100 mg) and 3-caffeoylquinic acid (1109 μg per 100 mg) in higher amounts, whereas the 80% methanol extract contains methoxyluteolin-7-O-rutinoside and catechin derivatives as major compounds. Total phenolic and flavonoid contents of the extracts were yielded in the range of 32.26-119.88 mg gallic acid equivalents g-1 and 0.60-2.39 mg rutin equivalents g-1 , respectively. Total antioxidant capacity was also displayed in the range of 0.53-6.34 mmol Trolox equivalents (TE) g-1 . Both the methanolic extracts showed higher total antioxidant capacity that could be related to the total phenolic contents. Radical scavenging capacity in DPPH (2,2-diphenyl-2-picryl-hydrazyl) (37.21-508.30 mg TE g-1 ) and ABTS [2,2-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid)] (60.95-1068.06 mg TE g-1 ) assays, reducing power in cupric ion reducing antioxidant capacity (54.23-1002.78 mg TE g-1 ) and ferric ion reducing antioxidant power (33.18-558.68 mg TE g-1 ) assays, as well as metal chelating activity (2.45-11.28 mg EDTA equivalents g-1 ), were exhibited by all extracts. All extracts were found to inhibit acetylcholinesterase [0.23-2.47 mg galanthamine equivalents (GALAE) g-1 ], tyrosinase [27.20-83.33 mg kojic acid equivalents g-1 ], amylase [mmol acarbose equivalents (ACAE) g-1 ]. On the other hand, all extracts, except the water extract, inhibited butyrylcholinesterase (5.38-6.56 mg GALAE g-1 ), whereas only the water and ethyl acetate extract showed glucosidase inhibitory potential (1.96 and 1.82 mmol ACAE g-1 ). In general, the water extract was found to be a weaker enzyme inhibitor suggesting that water is not the preferrable extraction solvent to obtain active products. The present study demonstrated that the stem bark extracts of P. biglobosa contains good amount of phytochemical and extracts present significant antioxidant, as well as reasonable enzyme inhibitory effects. Hence, these findings suggest that further studies can be performed on more specific biological targets and models of bioactivity to determine their safe usage as a nutraceutical or for the preparation functional foods. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Hydroalcoholic extract: A potential source from Azadirachta indica a Juss flower for DNA and BSA binding, scavenging, fungicidal, and larvicidal activities

AbstractThe present study focuses on the evaluation of the DNA and BSA binding capability, anti‐fungal, metal chelation, and larvicidal activity of extracts of Azadirachta indica A Juss flower. The different extracts of A. indica was prepared by soxhlet extraction using Petroleum Ether (PE), acetone (AC), and hydroalcohol (HA) as solvents. DNA and BSA binding ability of HA extract was calculated through the UV–Visible titrimetric method. The phytochemicals present in the extract show good binding ability towards DNA and BSA. H2O2 and NO scavenging activity were evaluated and HA extracts shows good antioxidant activity with IC50 values of 62 and 48 μg/mg, respectively. The metal chelating property was calculated, where HA shows good chelating ability with the IC50 value of 32.23 μg/mg. The antifungal activity of these extracts was evaluated against different fungal stains; among them, hydroalcoholic extract shows a higher zone of inhibition in all the fungal stains than Petroleum Ether and acetone extracts and acetone extracts (i.e., 50 μg/μL MIC). The potential extract (i.e., HA extract) was used to estimate the larvicidal activity of parasites. The % of mortality was evaluated through a dose‐dependent assay and it is confirmed that when concentration increases, the mortality rate increases. The correlation between metal chelating activity and total flavonoid and phenolic content was calculated and it was found that there is a good correlation (R2 – .743 and .902, respectively). These results proved that HA extract possesses biologically important phytochemicals that contribute to pharmaceutical and biological activities and could be a natural remedy for various real‐time applications.

Phytochemical and Antioxidant Activity of Water and Methanol Extracts of Oldenlandia corymbosa

Background: Oldenlandia corymbose is a small perennial herb used traditionally to clear toxins, activate blood circulation, and relieve urinary obstruction. Objectives: This study investigated the phytochemical and antioxidant activity of water and methanol extracts of Oldenlandia corymbosa. Materials and Methods: Total phenolic, flavonoids, and tannin contents of Oldenlandia corymbosa were determined using Folin-Ciocalteau reagent, Colorimetric AlCl3 method, and spectrophometry method respectively. The antioxidant activities were analyzed using 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), metal chelating activity (MCA), 2,2’-azino-bis-(3-ethyl) benzothiazoline-6-sulfonic acid (ABTS) radical scavenging, and phosphomolybdenum assay (PMA). Results: The total phenolic, flavonoid and tannin of the methanolic extracts were found to be higher than that of the water extracts. The DPPH, FRAP, MCA, ABTS and PMA for the water extracts were found to be 56.05 ± 0.1 %, 0.018 ± 0.002 mg Fe(II) equivalent/g, 0.346 ± 0.04 mg EDTA equivalent/g, 63.67 ± 0.6 mg trolox equivalent/g, 0.82 ± 0.03 ascorbic acid equivalents/g and greater than that of the methanol extract 47.26 ± 0.09 %, 0.009 ± 0.0001 mg Fe(II) equivalent/g, 0.198 ± 0.002 mg EDTA equivalent/g, 62.68 ± 0.7 mg trolox equivalent/g and 0.365 ± 0.008 ascorbic acid equivalents/g respectively. These results show that, though the methanol extracts contain more polyphenolic compounds, the water extract exhibits more antioxidant activity. Conclusion: The water extract of Oldenlandia corymbosa shows superior antioxidant activity due to the synergistic effects of its phytoconstituents than that of methanol extracts and can serve as a natural remedy for managing oxidative stress.

Phytochemical Screening, In vitro Antioxidant, Antibacterial Activities on Skimmia laureola Leaves Extract: A Research

Background: Skimmia laureola owned by the Rutaceae family is one of the plants that might use the Indian traditional treatment system in the Indian subcontinent and act against many diseases. So, this new research was carried out to scientifically confirm the various solvent fractions and separate the active fraction from the plant against antioxidants and bacterial and microbial growth.
 Objectives: The main objective of the study involves the Phytochemical screening and research of invitro activities i.e. antioxidant and antibacterial from the extracts of the leaves part of the Skimmia laureola plant.
 Methods: Phytochemical screening was carried out of various extracts by the tests that involved it. Invitro antibacterial and antioxidant activities were examined of the plant extract through various methods DPPH, Metal chelating activity, Reducing power ability, Hydrogen peroxide scavenging activity, and Nitric oxide scavenging activity. After completion of the research, all the activity is shown graphically.
 Results: Invitro antioxidant activity shows that methanolic extract shows more antioxidant activity than other extracts. The antibacterial investigations show that the ethanolic extract of the plant removal was very compelling for bacterias Streptococcus aureus, Bacillus subtilis, and Escherichia coli at 25 μg/ml, 50 μg/ml, 75 μg/ml, 100 μg/ml, 200 μg/ml and 300 μg/ml individually.
 Conclusion: Auxiliary metabolites (phenol, flavonoid, tannin, and content) have been quantified. In antioxidant tests such as DPPH activity, the methanolic extract of the plant outperforms other extracts such as chloroform, petroleum ether, ethanol, and aqueous extract. The antibacterial investigations show that the ethanolic extract of the plant removed was very compelling for bacterias Streptococcus aureus, Bacillus subtilis, and E.coli. The current study may be useful in improving data regarding its distinguishing proof boundaries expected primarily in the method of the adequacy of homegrown medications in the current situation lacking administrative laws to control the nature of natural medications, as well as discovering antioxidants and antibacterial action.

Kwas alfa-liponowy w prewencji powikłań cukrzycowych

Diabetes is a group of metabolic disorders characterized by a high blood sugar level (hyperglycemia) over a prolonged period of time. Diabetes is due to either the pancreas not producing enough insulin, or the cells of the body not responding properly to the insulin produced (insulin resistance). Chronic hyperglycemia is associated with damage of small and large blood vessels in many tissues and organs (micro- and macroangiopathy). Microvascular complications may contribute to the diabetic retinopathy and neuropathy. Diabetes is strongly associated with increased oxidative stress, which could be a consequence of either increased production of free radicals or reduced antioxidant defenses. Many of the biochemical pathways (e.g., protein glycation, polyol pathway, protein kinase C activation) associated with hyperglycemia can result in increased reactive oxygen species. An ideal therapeutic antioxidant should fulfill several criteria. These include absorption from the diet, conversion in cells and tissues into usable form, a variety of antioxidant actions (including interactions with other antioxidants) in both membrane and aqueous phases, and low toxicity. Alpha-lipoic acid is unique among natural antioxidants in its ability to fulfill all of these requirements. Alpha-lipoic acid has been shown to have diverse beneficial effects suggesting that it acts by multiple mechanisms on oxidative stress parameters. Alpha-lipoic acid’s antioxidant properties consist of the following: 1) its capacity to directly scavenge reactive oxygen species, 2) its ability to regenerate endogenous antioxidants, such as glutathione, vitamins E and C, and 3) its metal chelating activity, resulting in reduced reactive oxygen species production. Alpha-lipoic acid prevents micro-vascular damage through normalized pathways downstream of mitochondrial overproduction of reactive oxygen species. Alpha-lipoic acid inhibits diabetes-induced apoptosis of both endothelial cells and pericytes, signs and predictor of retinopathy, and prevents nerve ischemia and hypoxia whitch could cause neuropathy. Alpha-lipoic acid supplementation is an achievable adjunct therapy to help prevent vision loss and reduce neuropathic symptoms in diabetic patients. Honokiol is a natural polyphenolic compound extracted from the bark, cone and leaves of Magnolia. Honokiol is used in traditional Chinese and Japanese medicine for the treatment of various diseases. This promising bioactive compound presented an wide range of therapeutic and biological activities which include neuroprotective, anti-spasmodic, antidepressant, anti-tumorigenic, antithrombotic, antimicrobial, analgesic properties, and others. Some of its mechanism for exhibiting its pharmacological effects includes inhibition of oxidative stress and suppression of pro-inflammatory cytokines (TNF-α, IL-10 and IL-6). Honokiol might exert its protective effect on hyperglycemia-induced cell damage in human endothelial cells through the inhibition of NF-κB and COX-2 upregulation. Low-dose of honokiol may have the potential to protect endothelial cells from damage associated with elevated glucose.

The Antioxidant Capacities and Antimicrobial Activities of Some Salvia L. Seeds

The goal of present study is to find the penolic contents, antioxidant activities and antimicrobial capacities in the seeds of five Salvia L. taxa two of which are endemics (Salvia euphratica var. leiocalycina and Salvia euphratica var. euphratica). The flavonoid and phenolic acid are determined by using HPLC while the antioxidant activities are determined based on different methods. Also, the antimicrobial activities of some Salvia species are determined by using the well agar method. The current study found that the studied Salvia species have low flavonoid. It has been found that Salvia euphratica var. euphratica has high vanillic acid, ferulic acid and rosmarinic acid among the studied taxa. Similarly, it has been found that Salvia euphratica var. euphratica has high DPPH and ABTS radical scavening capacity in all concentrations. It has been also found that Salvia euphratica var. euphratica has highest total phenolic content (372,63±0,87 µgGAE/mg) whilst Salvia tricholoda has low total phenolic content (46,41±1,71 µgGAE/mg). In addition, this study demonstrated that Salvia tricholoda has lowest metal chelating activity (37,35±0,51%). Furthermore, present study found that the lipid peroxidation levels of the studied Salvia taxa are between 18,21±0,37 mg/kg and 21,03±0,22 mg/kg while it has been found that the antibacterial properties of the Salvia taxa under study are altering.

Production, characterization and in vitro biological activities of crude pigment from endophytic Micrococcus luteus associated with Avicennia marina.

Due to their non-toxic and non-carcinogenic nature, biopigments have a phenomenal benefit over synthetic pigments, making them a desirable source for human utilization and a potential alternative to traditional synthetic pigments that are hazardous to the environment and public health. Endosymbiotic interactions between mangrove plants and bacteria could provide an alternate source for the synthesis of unique compounds with potent biomedical applications. Pigmented endophytic bacteria were screened from the explants of Avicennia marina, a mangrove plant, and identified as Micrococcus luteus by molecular characterization. The intracellular pigment was successfully extracted using the sonication-assisted solvent extraction method, and screening factors impacting the pigmentation bioprocess were determined using a one-factor-at-a-time approach. The endophyte produced yellow pigment in the liquid medium, with the maximum growth and pigment production recorded in nutrient broth at 37℃ and pH 7 after 96h of incubation, while the maximum accumulation of pigment was observed in the media supplemented with glucose and tryptone as carbon and nitrogen sources, respectively. The extracted crude pigment was further characterized by ultraviolet, followed by Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry. The obtained crude pigment has been evaluated for its antioxidant and anticancer activity by various assays, such as DPPH radical scavenging activity, FRAP assay, superoxide anion and nitric oxide radical scavenging, metal chelating activity, phosphomolybdenum assay, and MTT assay, respectively, at varying concentrations. The results of our study revealed that the yellow pigment produced by the endophyte showed significant dose-dependent antioxidant and anticancer activity.

Exploring for HPLC-MS/MS Profiles and Biological Activities of Different Extracts from Allium lycaonicum Siehe ex Hayek from Turkey Flora.

The present study was designed to determine the phenolic constituents, antioxidant, and enzyme inhibition activities of aerial parts and bulbs of Allium lycaonicum (family Amaryllidaceae). Extracts were prepared by maceration and Soxhlet/infusion using hexane, methanol, and water as extraction solvents. Generally, extracts from the aerial parts showed higher total phenolic and individual components and antioxidant activity than their respective bulb extracts. Maceration with water was the best to extract total phenolic content from the aerial parts (29.00 mg gallic acid equivalents (GAE)/g), while the Soxhlet extraction with hexane (22.29 mg GAE/g) was the best for the bulb. Maceration with methanol recovered the highest total flavonoid content from both the aerial parts (41.95 mg (rutin equivalents (RE)/g) and bulb (1.83 mg RE/g). Polar extracts of aerial parts were characterized by higher abundance of kaempferol-3-glucoside (≤20,624.27 µg/mg), hyperoside (≤19,722.76 µg/g), isoquercitrin (≤17,270.70 µg/g), delphindin-3,5-diglucoside (≤14,625.21 µg/g), and rutin (≤10,901.61 µg/g) than the bulb. Aerial parts' aqueous extract, prepared by maceration, exerted the highest anti-ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical activity (64.09 mg trolox equivalents (TE)/g), Cu++ (83.03 mg TE/g) and Fe+++ (63.03 mg TE/g) reducing capacity while that prepared by infusion recorded the highest anti-DPPH (2,2-diphenyl-1-picrylhydrazyl) radical (31.70 mg TE/g) and metal chelating (27.66 mg EDTAE/g) activities. The highest total antioxidant activity (1.46 mmol TE/g) was obtained by maceration of the bulb with water. Extracts obtained by organic solvents showed remarkable enzyme inhibition properties against the tested enzymes. Soxhlet extraction of the bulb with hexane and methanol recorded the highest acetylcholinesterase inhibition (4.75 mg galanthamine equivalents (GALAE)/g) and tyrosinase inhibition (139.95 mg kojic acid equivalents/g) activities, respectively. Extracts obtained by maceration of the bulb with methanol and the aerial parts with hexane exerted the highest glucosidase inhibition (3.25 mmol acarbose equivalents/g) and butyrylcholinesterase inhibition (20.99 mg GALAE/g) activities, respectively. These data indicated that A. lycaonicum is a source of bioactive molecules with potential antioxidant and enzyme inhibition properties. Nonetheless, the extracts obtained through various solvents and extraction techniques showed variations in their phytoconstituent composition and biological properties.

Galanthus elwesii Hook.f.’nin Farklı Ekstraktlarının Serbest Radikal Yakalama ve Metal Şelatlama Aktivitelerinin Tespit Edilmesi

Natural compounds play an important role among antioxidants that protect the human body against oxidative stress. Many plants may have high levels of antioxidant capacity through the compounds they contain. In line with this information, in the current study, we aimed to evaluate the antioxidant properties of Galanthus elwesii Hook.f. In this context, we tested the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and metal chelating activities of different concentrations (12.5-400 mg/L) of methanol and water extracts obtained from the bulb part of this plant. A concentration-dependent increase in activity was observed for both extracts. DPPH scavenging (87.10%) and metal chelating (72.99%) activities demonstrated by 400 mg/L concentration applications came to the fore. In addition, it was determined that these data were significantly (p < 0.05) higher than the activity rates revealed by other applications. Considering the IC50 values, low values for DPPH scavenging and metal chelating activities (110.88 mg/L and 132.40 mg/L, respectively) were detected in water extracts. As a result, the importance of G. elwesii among plants that have the potential to be a rich source of antioxidants was revealed in this study.

Genomic Insights into the Microbial Agent Streptomyces albidoflavus MGMM6 for Various Biotechnology Applications.

Microbial biotechnology plays a crucial role in improving industrial processes, particularly in the production of compounds with diverse applications. In this study, we used bioinformatic approaches to analyze the genomic architecture of Streptomyces albidoflavus MGMM6 and identify genes involved in various metabolic pathways that have significant biotechnological potential. Genome mining revealed that MGMM6 consists of a linear chromosome of 6,932,303 bp, with a high G+C content of 73.5%, lacking any plasmid contigs. Among the annotated genes, several are predicted to encode enzymes such as dye peroxidase, aromatic ring-opening dioxygenase, multicopper oxidase, cytochrome P450 monooxygenase, and aromatic ring hydroxylating dioxygenases which are responsible for the biodegradation of numerous endogenous and xenobiotic pollutants. In addition, we identified genes associated with heavy metal resistance, such as arsenic, cadmium, mercury, chromium, tellurium, antimony, and bismuth, suggesting the potential of MGMM6 for environmental remediation purposes. The analysis of secondary metabolites revealed the presence of multiple biosynthesis gene clusters responsible for producing compounds with potent antimicrobial and metal-chelating activities. Furthermore, laboratory tests conducted under controlled conditions demonstrated the effectiveness of MGMM6 in inhibiting phytopathogenic microbes, decolorizing and degrading aromatic triphenylmethane dyes, particularly Blue Brilliant G250, from wastewater by up to 98 ± 0.15%. Overall, the results of our study highlight the promising biotechnological potential of S. albidoflavus MGMM6.

Phytochemical Analysis, In Vitro Free Radical Scavenging, and LDL Protective Effects of Different Solvent Fractions of Calotropis procera (R.) Br. Root Bark Extract

In the present study, the methanolic extract of Calotropis procera root bark was subjected to solvent-solvent partitioning using n-hexane fraction (HF), dichloromethane fraction (DMF), ethyl acetate fraction (EAF), and methanol fraction (MF). The resultant fractions were tested for antioxidant activity using in vitro radical scavenging assay. Preliminary phytochemical investigation revealed the presence of varying proportions of secondary metabolites in solvent fractions such as glycosides, flavonoids, triterpenoids, sterols, and polyphenolic compounds. The total phenolic content of EAF was 25.7 ± 3.12 mg TAE/g followed by 19.05 ± 3.29 mg TAE/g in DMF. The total flavonoid content was 13.69 ± 1.74 mg QUE/g in DMF and 11.4 ± 1.88 mg QUE/g in EAF. The EAF showed significant radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH, IC50 = 369.87 μg/mL), nitric oxide (IC50 = 317.46 μg/mL), hydrogen peroxide (H2O2 , IC50 = 396.85 μg/mL), and hydroxyl radicals (IC50 = 195.39 μg/mL). DMF was most effective in scavenging superoxide radicals (IC50 = 679.60 μg/mL), while greater metal chelating activity was exhibited by MF (IC50 = 614.73 μg/mL). Moreover, the total antioxidant activity for EAF was found to be 94.14 ± 9.114 mg AAE followed by DMF (68.10 ± 8.78 mg AAE). EAF also significantly reduced the formation of thiobarbituric acid reactive substances in a dose-dependent manner in CuSO4. The observed antioxidant effect might be attributed to the presence of secondary metabolites. Subsequent GC-MS analysis of EAF confirmed the presence of lupeol, α-amyrin, β-amyrin, and ursolic acid. The current investigation reveals that the high polyphenolic and antioxidant pentacyclic triterpenes in EAF of C. procera root bark methanol extract correlates with its good antioxidant activity and can provide protection against free radicals-induced damage in a variety of chronic health conditions.

Effects of black seed oil combined with olive oil or honey on antioxidant activities, phenolic content, and identification and quantification of thymoquinone, a key bioactive compound

The plant Nigella sativa (NS) has a rich history in folk medicine, being utilized for various illnesses and as tonic drugs. Furthermore, thymoquinone (TQ), a major compound found in the seeds of NS, may exhibit antioxidant activity. In addition to black candles, traditional medicine employs olive oil and honey to nourish the body. Some folk medicine systems combine NS, honey, and olive oil for improved efficacy; however, knowledge regarding the antioxidant properties of black seed oil (BSO), BSO with olive oil (BSOO), and BSO with honey (BSOH) remains limited. Therefore, in this study, we investigated the antioxidant properties of BSO, BSOO, and BSOH. Gas chromatography-mass spectrometry analysis showed that BSO contained 73.48 ± 1.23 mg/kg TQ. BSO, BSOO, and BSOH exhibited remarkable antioxidant activity, with NO scavenging activities of 94.32, 76.53, and 50.37, respectively. The 2,2-diphenyl-1-picrylhydrazyl and metal chelating activity assays (with half-maximal inhibitory concentration values), oxygen radical antioxidant capacity, and total flavonoid compound content of BSO were 0.135 ± 0.003 mg/mL, 0.005 ± 0.003 mg/mL, 32 ± 0.4 μM Trolox/g extract, and 997 ± 20 mg catechin equivalent/g of extract, respectively. These results are potentially linked to the increased antioxidant activity, as suggested by Pearson's correlation coefficients. In the ferric-reducing antioxidant power assay, the highest antioxidant activity was demonstrated by BSOO and BSOH, with total phenolic content of 7288 ± 300 mM FeSO4/mg and 346 ± 17 mg of gallic acid equivalent/g E, respectively. This study affirms the potent antioxidant properties of BSO, BSOO, and BSOH, emphasizing the importance of further research on NS infusion as a promising antioxidant agent and its application as an anti-aging and tonic drug.