Microwave-assisted Green Synthesis of β-Diketone Hydrazone Derivatives and Evaluation of their Antioxidant and Antibacterial Activities

2020 ◽  
Vol 7 (3) ◽  
pp. 222-229
Author(s):  
Syed Tajudeen Syed Ameen ◽  
Anbalagan Vilvanathan ◽  
Syed Zameer Ahmed Khader ◽  
Gayathri Mahalingam

Background: A series of β-diketone hydrazones have been synthesized via condensation of isoniazid with series of β-diketone. The structures of the Schiff bases are established by elemental and spectroscopic techniques. The prepared compounds were screened for antibacterial and antioxidant potential by DPPH free-radical scavenging activity and Ferric reducing antioxidant power (FRAP) assays. Methods: β-diketone hydrazine derivatives were synthesized by simple condensation between various β-diketones and isoniazid. The titled compounds were synthesized following both conventional and microwave irradiation methods. The in vitro antibacterial activity of synthesized derivatives was evaluated against gram-positive (B. subtilis, S. aureus and S. pyogenes) and gram-negative (E. coli, and K. pneumonia) bacterial strains and expressed in terms of zone of inhibition and also screened for antioxidant activity. Results: The yield of products was appreciably increased in shorter reaction times with the aid of microwave-assisted synthesis. Therefore, it follows the green chemistry approach by making the above reactions eco-friendly. The synthesized compounds were characterized using FT-IR, 1H NMR, 13C NMR, and elemental analysis techniques. The spectroscopic techniques showed the formation of β-diketone hydrazone compounds. Theoretical data show good agreement with the experimental results. Some of the compounds displayed significant antibacterial and antioxidant potentials when compared to the standard drug. Conclusion: In the present research work, we report the synthesis of some novel β-diketone hydrazone derivatives. A high yield of compounds was noted under microwave-assisted reaction in shorter reaction times. The results revealed that the synthesized Schiff bases showed good radical scavenging activity.

2021 ◽  
Vol 18 ◽  
Author(s):  
Sarosh Iqbal ◽  
Shumaila Kiran ◽  
Shahida Perveen ◽  
Rizwana Malik ◽  
Muhammad Taha ◽  
...  

Background & Introduction : Antioxidants are known to prevent oxidative stress-induced damage to the biomolecules and thus, delay the onset of cancers and many age-related diseases. Therefore, the development of novel and potent antioxidants is justified. Method: During this study, we synthesized symmetrical bis-Schiff bases of carbohydrazide 1-27, and evaluated their in vitro antioxidative activity and cytotoxic activity. Results: Among synthesized compounds, six compounds 20 (IC50 = 12.89 ± 0.02 µM), 16 (IC50 = 14.32 ± 0.43 µM), 17 (IC50 = 18.52 ± 0.83 µM), 19 (IC50 = 22.84 ± 0.62 µM), 24 (IC50 = 35.1 ± 0.82 µM) and 15 (IC50 = 40.03 ± 1.06 µM) showed an excellent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, better than the standard butylatedhydroxyanisole (BHA) (IC50 = 44.6 ± 0.6 µM). Likewise, two compounds 16 (IC50 = 4.3 ± 1.3 µM) and 20 (IC50 = 6.6 ± 1.6 µM) showed oxidative burst scavenging activity better than the standard drug ibuprofen (IC50 = 11.2 ± 1.9 µM). Some synthesized compounds showed good to moderate toxicity against prostate cancer (PC-3) cell lines. Conclusion: This study has identified potent antioxidants and good cytotoxic agents with the potential to further investigate.


2014 ◽  
Vol 9 (2) ◽  
pp. 149-155 ◽  
Author(s):  
Mirjana Marčetić ◽  
Silvana Petrović ◽  
Marina Milenković ◽  
Marjan Niketić

AbstractThe chemical composition, antimicrobial and antioxidant activity of Eryngium palmatum, an endemic plant species from the Balkan Peninsula, were investigated. The flavonoids apigenin (9.5±0.3 mg g−1) and apigenin 7-O-glucoside (2.4±0.1 mg g−1) were determined in a methanol extract of aerial parts using HPLC analysis. The methanol extract of roots contained catechin (5.0±0.1 mg g−1), epicatechin (2.9±0.1 mg g−1), chlorogenic acid (1.6±0.0 mg g−1), gallic acid (0.9±0.0 mg g−1) and rosmarinic acid (0.9±0.2 mg g−1). GC-FID and GCMS analysis of a chloroform extract of aerial parts showed that the main volatile constituents were falcarinol, linoleic acid, hexadecanoic acid and methyl linoleate (comprising 32.6%; 24.4%; 19.9; 13.2% of the volatile fraction, respectively), while octanoic acid, tetradecanol and dodecanol dominated in the chloroform extract of the roots (34.9%; 25.8%; 22.2% of the volatile fraction, respectively). Investigation of antimicrobial activity by broth microdilution showed that the methanol and chloroform extracts of aerial parts and roots exerted a significant effect (MIC 3.5–15.6 μg mL−1) against tested Gram-positive and Gram-negative bacteria. The methanol extracts of aerial parts or roots exerted moderate ferric reducing antioxidant power, DPPH radical scavenging activity and hydroxyl radical scavenging activity.


2017 ◽  
Vol 1130 ◽  
pp. 623-632 ◽  
Author(s):  
Çiğdem Albayrak Kaştaş ◽  
Gökhan Kaştaş ◽  
Aytaç Güder ◽  
Mahmut Gür ◽  
Halit Muğlu ◽  
...  

2020 ◽  
Vol 42 (1) ◽  
pp. 109-109
Author(s):  
Hao Zang Hao Zang ◽  
Qian Xu Qian Xu ◽  
Luyun Zhang Luyun Zhang ◽  
Guangqing Xia Guangqing Xia ◽  
Jiaming Sun and Junyi Zhu Jiaming Sun and Junyi Zhu

A series of hydroxytyrosol (HT) derivatives were synthesized by modification of alcohol hydroxyl group of HT, twenty-five target compounds were obtained and characterized by NMR and HRMS. The antioxidant activities of those compounds were evaluated in three different assays. Except 3e and 3y, all other compounds demonstrated significant 2,2and#39;-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radical cation scavenging activity ranging from IC50 3.4 to 24.4 μM, which were more potent than L-ascorbic acid (IC50=24.8 μM). Compounds 3b-3d, 3f-3k, 3m-3x were better than Trolox (18.3 M). Moreover, the ferric reducing antioxidant power (FRAP) of all compounds were discovered to be more potent than L-ascorbic acid (40.7 mmol/g), except 3e, all other compounds (141.5-202.1 mmol/g) were better than Trolox (94.7 mmol/g). Compounds 3a-3d, 3f-3j, 3l-3m, 3o, 3q, 3t, 3v-3y exhibited more potent hydroxyl radical scavenging activity (IC50=245.1-475.1 M) than L-ascorbic acid (554.4 M) and Trolox (500.4 M). Compounds 3q, 3t and 3y exhibited more potent -Glucosidase inhibition activity (39.1-52.4 M) than Acarbose (60.9 M). Compounds 3a, 3d, 3f-3m, 3s-3t, 3v-3y showed some acetylcholinesterase inhibition activities, compounds 3a, 3d, 3f-3j, 3l-3m, 3o-3p, 3s-3t, 3w showed some butyrylcholinesterase inhibition activities.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Sushil Kumar Middha ◽  
Talambedu Usha ◽  
Veena Pande

This study revealed polyphenolic content, nutritive content, antioxidant activity, and phenolic profile of methanol and aqueous extracts ofPunica granatumpeel extract. For this, extracts were screened for possible antioxidant activities by free radical scavenging activity (DPPH), hydrogen peroxide scavenging activity and ferric-reducing antioxidant power (FRAP) assays. The total phenolics and flavonoid recovered by methanolic (MPE) and the water extract (AQPE) were ranged from 185 ± 12.45 to 298.00 ± 24.86 mg GAE (gallic acid equivalents)/gm and 23.05 ± 1.54 to 49.8 ± 2.14 quercetin (QE) mg/g, respectively. The EC50of herbal extracts ranged from 100 µg/ml (0.38 quercetin equivalents), for AQPE, 168 µg/ml (0.80 quercetin equivalents), for MPE. The phenolic profile in the methanolic extracts was investigated by chromatographic (HPLC) method. About 5 different flavonoids, phenolic acids, and their derivatives including quercetin (1), rutin (2), gallic acid (3), ellagic acid (4), and punicalagin as a major ellagitannin (5) have been identified. Among both extracts, methanolic extract was the most effective. This report may be the first to show nutritive content and correlation analysis to suggest that phenols and flavonoids might contribute the high antioxidant activity of this fruit peel and establish it as a valuable natural antioxidant source applicable in the health food industry.


2017 ◽  
Vol 15 (2) ◽  
pp. 157-167
Author(s):  
Prabhakar Kumar VERMA ◽  
Mukesh KUMAR ◽  
Nelam MALIK ◽  
Priyanka DHIMAN ◽  
Anurag KHATAHAR

A series of 20 new biologically active derivatives of 2-{4, 5-(substituted diphenyl)-4H-1,2,4-triazol-3-ylthio}acetyl chloride has been synthesized, with the aim to investigate antimicrobial, free radical scavenging activity. All the synthesized compounds were characterized by spectroscopic data and elemental analysis. The final compounds were tested for antibacterial activity against Gram-positive bacteria: Staphylococcus aureus MTCC 3160, Bacillus subtilis MTCC 441; Gram-negative bacteria: Escherichia coli MTCC 443, and, for antifungal activity, against Candida albicans MTCC 227 and Aspergillus niger MTCC 281, taking ciprofloxacin as antibacterial and fluconazole as antifungal standard drugs. Compound 7a6 was found to be the most effective antibacterial (MIC = 3.12 µg/ml), and compounds 7a2 and 7d1 (MIC = 3.12 and 6.25 µg/ml) had the most effective antifungal effects on the selected strains, as compared to the standard drugs. The results of antioxidant studies revealed that compound 7b1 was found to be most active antioxidant, with 40.4±0.687 µg/ml, and compounds 7b3, 7d7, and 7d4 also showed promising free radical scavenging activity, as compared with the standard drug ascorbic acid.


2021 ◽  
Author(s):  
Ahmed Al-Mustafa ◽  
Mohammad Al-Tawarah ◽  
Mohammed Sharif Al-Sheraideh ◽  
Fatima Attia Al-Zahrany

Abstract Background: We investigated Juniperus Phoenicea (J. Phoenicea) and Calicotome Villosa (C. Villosa) from Jordan for phenolic contents, antioxidant, anti β-Galactosidase activities, in an attempt to rationalize its use in lactose metabolism disorders. The kinetic parameters of leave extracts, galactose, glucose, fructose and acarbose were evaluated. Also, the thermodynamic parameters of the enzyme thermal inactivation were determined. Methods: JP and cv crude methanolic extracts were evaluated for 1,1-diphenyl,2-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power (FRAP). Further, β-Galactosidase inhibitory activities were performed using O-nitrophenyl-beta-D-galactopyranoside as substrate. Moreover, total phenolic contents, flavonoids and flavonols of plants extracts were determined and expressed in mg of gallic acid equivalent (mg GAE/g dry extract) or rutin equivalent per gram of dry extract (mg RE/g dry extract).Results: Phytochemical screening of the crude extract of J. Phoenicea and C. Villosa leaves contained phenols, alkaloids, flavonoids, terpenoids, anthraquinones and glycosides. J. Phoenicea exhibited high flavonoids and flavonols contents than C. Villosa but both J. Phoenicea and C. Villosa contained high phenolic and showed concentration dependent DPPH scavenging activity, with J. Phoenicea (IC50 =11.1 μg/ml), C. Villosa (IC50 =15.6 μg/ml), respectively. According to FRAP assay, the antioxidant power activity of plants extracts was concentrations dependent. The β-galactosidase % inhibition was increased as the concentration of of J. phoenicea, C. villosa and rutin increased. The mode of inhibition of β-galactosidase by J. phoenicea (IC50= 65 µg/ml) and C. villosa (IC50= 700 µg/ml) extracts was non-competitive and mixed-inhibition, respectively. Also, rutin was affected in a competitive (IC50 = 75 µg/ml) inhibition. β-galactosidase half-life was 108 min at 55°C, thermodynamic parameters revealed an activation energy of 208.88 kJ mol-1 and the inactivation kinetic follows a first-order reaction with k-values ranges between 0.0862 and 0.0023 min-1. The enzyme showing a decreasing trend of enthalpy of denaturation (∆H°) as temperature increase but value of free energy of thermal denaturation (∆G°) for β-galactosidase was decreased with increasing in temperature. The calculated entropy of inactivation (∆S°) at each temperature showed positive values, which means there are no significant processes of aggregation.Conclusions: J.phoenicea and C.villosa have inhibiting effect on β-galactosidase activity. Thermodynamic approach shows an enzyme stable and suggests that inactivation mechanism is based on molecular structural changes.


2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Herath Pathiranage Thathmi Wathsara ◽  
Hasitha Dhananjaya Weeratunge ◽  
Mohamed Naeem Ahammadu Mubarak ◽  
Pahan Indika Godakumbura ◽  
Pathmasiri Ranasinghe

Syzygium caryophyllatum L. Alston (Family: Myrtaceae, Sinhala: Heendan) is a red-listed plant that has been used in traditional medicine in Sri Lanka for the treatment of diabetes, but it is yet to be exploited for its potential uses as a functional food or a source of supplements. The present study focused on the evaluation of antidiabetic property of S. caryophyllatum fruits and leaves assessing antioxidant, antiglycation, and antiamylase activities and functional mineral element composition. The crude extracts (CR) of leaves and fruits were fractionated into hexane (Hex) ethyl acetate (EA) and aqueous (AQ) and evaluated for bioactivities along with the crude extracts. The isolated fraction (C3) of Hex fraction of fruit showed significantly high (p<0.05) antiamylase activity with IC50 value 2.27 ± 1.81 μg/mL where the Hex fraction of fruits exhibited the IC50 value as 47.20 ± 0.3 μg/mL which was higher than acarbose (IC50: 87.96 ± 1.43 μg/mL). The EA fraction of leaves showed highest values for DPPH radical scavenging activity, ferric reducing antioxidant power, and oxygen radical absorbance capacity. Significantly high (p<0.05) ABTS radical scavenging activity and iron chelating activity were observed in Hex fraction of fruit. The composition of volatiles in leaf oil was studied with GC-MS, and 58 compounds were identified. Inductively coupled plasma-mass spectrometry data revealed the presence of biologically significant trace elements such as Fe, Zn, Mg, Cu, Se, and Sr in leaves and fruits. It is concluded that the Hex fraction of S. caryophyllatum fruits will be a good source for the formulation of supplements for diabetic management with further evaluation of potency and efficacy.


2015 ◽  
Vol 20 (1) ◽  
pp. 97-101
Author(s):  
Khaga Raj Sharma ◽  
Achyut Adhikari ◽  
M. Iqbal Choudhary ◽  
Suresh Awale ◽  
Surya Kant Kalauni

Bioassay guided fractionation of ethyl acetate soluble fraction of methanolic extract of Bridelia retusa yielded tambulin (1), beta-sitosterol (2), and beta-sitosterol glucoside (3), and their structures were elucidated using modern spectroscopic techniques. Compounds 1-3 were evaluated for their antioxidant activity and compound 1 was found to be potent antioxidant. The DPPH assay showed that the compound 1 has potent antioxidant activity with IC50 166.15±1.92 SEM [muM] and the radical scavenging activity was found to be 86.03% where as the standard butylated hydroxy toluene (BHT) has IC50 value 128.83±2.1 SEM [muM]. The radical scavenging activity of standard butylated hydroxy toluene was about 86% .The total phenolic content in ethyl acetate soluble fraction was found to be 147.20±1.5 mg GAE/gm and the total flavonoid content was found to be 16.64±0.00 mg QE/gm.Journal of Institute of Science and Technology, 2015, 20(1): 97-101


2020 ◽  
Vol 10 (7) ◽  
pp. 2290 ◽  
Author(s):  
Paula Borrajo ◽  
Mirian Pateiro ◽  
Mohammed Gagaoua ◽  
Daniel Franco ◽  
Wangang Zhang ◽  
...  

In order to make the by-products generated from the porcine industry more valuable, pig livers were used in this trial to obtain protein hydrolysates. Three proteases (alcalase, bromelain, and papain) were utilized for enzymatic hydrolysis with two different durations, 4 and 8 hours. Ultrafiltration process was used for the recovery of the extracts, employing three different membrane pore sizes (30, 10, and 5 kDa). The porcine livers contained considerable amounts of protein (19.0%), considering they are almost composed of water (74.1%). The antioxidant activity of the obtained hydrolysates was investigated using four antioxidant methods (2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2-2′-Azino-di-[3-ethylbenzthiazoline sulfonate] (ABTS) radical scavenging activity, ferric reducing antioxidant power assay (FRAP), and oxygen radical absorbance capacity assay (ORAC)). Antibacterial properties were also measured against Gram-negative and Gram-positive bacteria. Results indicated that the three studied factors (type of enzyme, membrane pore size, and time) significantly affected the parameters evaluated. Hydrolysates obtained at 8 hours with alcalase had the best antioxidant properties. The 30 kDa alcalase extracts exhibited the highest DPPH (562 µg Trolox/g), FRAP (82.9 µmol Fe2+/100 g), and ORAC (53.2 mg Trolox/g) activities, while for ABTS the 10 kDa alcalase showed the higher values (1068 mg ascorbic acid/100 g). Concerning the antibacterial activity, 30 kDa hydrolysates obtained with bromelain for 4 hours exhibited the highest antimicrobial capacity, providing an inhibition of 91.7%.


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