Novel Mannich Base Derivatives: Synthesis, Characterization, Antimicrobial and Antioxidant Activities

2020 ◽  
Vol 17 ◽  
Author(s):  
Gül KOTAN

: In this study, 3-alkyl(aryl)-4-(4-ethylbenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 2 were synthesized as explained in the literature. Then, the Schiff bases 2 were treated with morpholine/ N-methylpiperazine/ 3-methylpiperidine/ 4-piperidinecarboxamide in the presence of formaldehyde according to the Mannich reaction to synthesize novel Mannich bases 3, 4, 5, and 6 types, respectively. The structural analyses of twenty four compound which synthesized new, were characterized using proton/ carbon 13 nuclear magnetic resonance (1H/ 13C-NMR), Infrared (IR) spectoscopic techniques. In addition, the antimicrobial activity of the compounds was determined on six bacteria by using the agar well diffusion method.The most effective results against gram positive and negative bacteria were observed in 6(a-d) and 6f compounds. Also, the antioxidant capacities of the substances were investigated by three different methods (DPPH, reducing power, metal chelation). All compounds 3-6(a-f) showed metal chelating effect.

2011 ◽  
Vol 6 (11) ◽  
pp. 1934578X1100601 ◽  
Author(s):  
Jihua Wang ◽  
Hao Liu ◽  
Haifeng Gao ◽  
Jianglin Zhao ◽  
Ligang Zhou ◽  
...  

The essential oil obtained by hydrodistillation from the flowers of Halimondendron halodendron (Leguminosae) was analyzed for its chemical composition by gas chromatography-mass spectrometry (GC-MS). Undecane (16.4%), dodecane (15.3%), tridecane (12.5%), decane (8.2%), 6,10,14-trimethyl-pentadecan-2-one (6.3%), methyl palmitate (6.0%), methyl linolenate (4.1%) and ethylcyclohexane (4.1%) were the major compounds of the thirty-five identified components of the oil. The essential oil was shown to have a broad spectrum of antimicrobial activity with MIC values ranging from 100 to 250 μg/mL, and IC50 values from 40.4 to 193.8 μg/mL. The oil also showed strong antioxidant activity, with an especially high metal chelating capacity of ferrous ions with an IC50 value of 7.4 μg/mL on ferrozine-Fe2+ complex formation.


2012 ◽  
Vol 2 (12) ◽  
pp. 487 ◽  
Author(s):  
Aleksandra Zambrowicz ◽  
Marta Pokora ◽  
Ewelina Eckert ◽  
Marek Szołtysik ◽  
Anna Dąbrowska ◽  
...  

Several biological activities have now been associated with egg protein- derived peptides, including antihypertensive, antimicrobial, immunomodulatory, anticancer and antioxidant activities, highlighting the importance of these biopeptides in human health, and disease prevention and treatment. Special attention has been given to peptides with antioxidant and antimicrobial activities as a new source of natural preservatives in food industry. In this study, the antioxidant properties of the egg-yolk protein by-product (YP) hydrolysates were evaluated based on their radical scavenging capacity (DPPH), Fe2+chelating effect and ferric reducing power (FRAP). Furthermore, antimicrobial properties of obtained hydrolysates against Bacillus species were studied. The degrees (DHs) of hydrolysis for 4h hydrolysates were: 19.1%, 13.5% and 13.0%, for pepsin, chymotrypsin and trypsin, respectively. Pepsin was the most effective in producing the free amino groups (1410.3 μmolGly/g). The RP-HPLC profiles of the protein hydrolysates showed differences in the hydrophobicity of the generated peptides. Trypsin hydrolysate obtained after 4h reaction demonstrated the strongest DPPH free radical scavenging activity (0.85 µmol Troloxeq/mg). Trypsin and chymotrypsin hydrolysates obtained after 4h reaction exhibited 4 times higher ferric reducing capacity than those treated by pepsin. The hydrolysis products obtained from YP exhibited significant chelating activity. The 4h trypsin hydrolysate exhibited weak antimicrobial activity against B. subtilis B3; B. cereus B512; B. cereus B 3p and B. laterosporum B6. Keywords: Antioxidative activity, DPPH, peptides, hydrolysis, egg-yolk protei


2006 ◽  
Vol 61 (4) ◽  
pp. 486-494 ◽  
Author(s):  
Kerstin Bischoff ◽  
Ulrich Girreser ◽  
Dieter Heber ◽  
Martin Schütt

The Mannich reaction of 7-aryl-5,6-dihydropyrido[2,3-d]pyrimidines 3, easily accessible by condensation of 6-amino-1,3-dimethyluracil (1) with Mannich bases 2a - c, gives rise to a mixture of 7-aryl-6-(N,N-dimethylaminomethyl)pyrido[2,3-d]pyrimidines 6 and 7 as well as 1,2-bis- (7-arylpyrido[2,3-d]pyrimidin-6-yl)ethane 13 the ratio of which depends on the reaction conditions and the amine used. 6-Alkylamino-1,3-dimethyluracils 15 - 18 were converted to the corresponding 5-(3-oxo-3-phenylpropyl)uracils 19 - 22 by condensation with the Mannich base 2a. Ring closure of 19 - 22 was performed by Vilsmeier formylation to afford the 8-alkyl- and 7,8-diaryl-5,8- dihydropyrido[2,3-d]pyrimidine-6-carbaldehydes 9 - 12 via the corresponding iminium salts 27 - 30


2013 ◽  
Vol 8 (5) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Pavle Mašković ◽  
Marija Radojković ◽  
Mihailo Ristić ◽  
Slavica Solujić

The objective of this study was to evaluate the potential use of the essential oil of Kitaibelia vitifolia Willd. in the pharmaceutical and food industries. Antimicrobial and antioxidant activities of essential oil of K. vitifolia isolated by hydrodistillation using a Clevenger-type apparatus were assessed. GC/FID and GC/MS analyses were used to determine the major components of the essential oil as sclareoloxide ( cis A/B) 17.9%, sclaral 10.9%, labda-7,13,14-triene 10.6% and sclareol 9.5%. The antimicrobial activity of the essential oil was evaluated against the bacterial strains: Staphylococcus aureus ATCC 25923, Klebsiella pneumoniae ATCC 13883, Escherichia coli ATCC 25922, Proteus vulgaris ATCC 13315, P. mirabilis ATCC 14153, and Bacillus subtilis ATCC 6633; and fungal strains: Candida albicans ATCC 10231 and Aspergillus niger ATCC 16404. Antimicrobial activity was tested using a broth dilution procedure for determination of minimum inhibitory concentration (MIC). The essential oil of K. vitifolia showed strong antimicrobial activity. Antioxidant activities of the essential oils were evaluated using the DPPH and hydroxy radical scavenging, lipid peroxidation and metal chelating assays. The results for antioxidant activity were compared with control antioxidants, ascorbic acid, gallic acid, α-tocopherol and BHT. Results showed that the essential oil possesses antioxidant activity, with total antioxidant capacity of 95.4±0.7 μg AA/g and IC50 values of 5.45±1.45 μg/mL for DPPH free radical scavenging activity, 26.5±1.6 μg/mL for inhibitory activity against lipid peroxidation, 79.4±0.4 μg/mL for hydroxyl radical scavenging activity, and 39.9±0.7 μg/mL for metal chelating activity.


2019 ◽  
Author(s):  
Chem Int

Oil extracted from Persea Americana seed was assayed for its physiochemical properties and antioxidant potential using various standard methods. The oil content of the seed was found to be < 10%. Brownish-red color oil was liquid at room temperature, with specific gravity of 0.91±0.02 g/mL. Other physiochemical parameters determined were; acid value (4.51±0.08 mgKOH/g), %FFA (2.26±0.08), peroxide value (2.40±0.57 mgO2/Kg), ester value (31.26±0.03 mgKOH/g), saponification value (35.76±0.07 mgKOH/g) and iodine value (23.5±0.07). The results of the antioxidant activities of the seed oil showed that the flavonoid content (80.00±1.41 mgQE/g) was ~10 folds higher than the phenolic content (8.27±0.06 mgGAE/g). The DPPH radical scavenging value was found to be 51.54±0.25% with an IC50 value of 4.68±0.02 mg/mL and reducing power with an average absorbance of 0.85±0.01 and an IC50 value of 0.001±0.02 mg/mL. Gallic acid showed better antioxidant activities than the oil studied. The results obtained in this study showed that Persea Americana seed oil has nutritional, industrial as well as medicinal potentials.


2016 ◽  
Vol 4 (11) ◽  
pp. 892-899
Author(s):  
AbdelKarim M. ◽  
◽  
Wafa O. ◽  
Nafesa A.G. ◽  
Inas O. ◽  
...  

2019 ◽  
Vol 20 (7) ◽  
pp. 573-587
Author(s):  
Alyaa Nasr ◽  
Tehmina Saleem Khan ◽  
Shi-Ping Huang ◽  
Bin Wen ◽  
Jian-Wen Shao ◽  
...  

Background: Eucalyptus belongs to the Myrtaceae family. It is the most planted hardwood forest crop worldwide, representing a global renewable resource of fiber, pharmaceuticals and energy. Objective: To compare the five species, E. maidenii, E. robusta, E. citriodora, E. tereticornis and E. camaldulensis, seeking for the richest source of nutrients and pharmaceuticals. Methodology: Eucalyptus samples were subjected to some chemical determinations for both primary and secondary metabolites to verify their nutritional and pharmaceutical importance related to different extracts. GC-MS analysis was applied to detect the presence of some individual phenolic constituents in their leaves. Results: E. robusta recorded the maximum contents of carbohydrates (40.07%) and protein (31.91%). While E. camaldulensis contained the highest contents of total phenolic compounds (46.56 mg/g), tannins (40.01 mg/g) and antioxidant activities assayed by the phosphomolybednum method (57.60 mg/g), followed by E. citridora. However, E. tereticornis exhibited the highest reducing power ability (151.23 mg/g). The GC-MS highlighted 20 phenolic constituents and antioxidants which varied in their abundance in Eucalyptus leaves, 8 individual phenolics (hydroquinone, hesperitin, pyrogallol, resorcinol, protocatechuic acid, naringenin, chlorogenic acid and catechin) were maximally recorded with E. camaldulensis and secondly, with E. citridora in case of at least 5 components. Nevertheless, gallic and quinic acids were more abundant in the leaves of E. tereticornis, which may explain its high corresponding reducing powers. Conclusion: Acetone-water combination has enhanced phenolics extraction from Eucalyptus tissues. This is the first report aiming to compare between the aforementioned Eucalyptus species highlighting either their nutritional or medicinal importance.


2020 ◽  
Vol 16 ◽  
Author(s):  
Mojgan Alizadeh ◽  
Akram Arianfar ◽  
Ameneh Mohammadi

Objective: Ziziphora clinopodioides is an edible medicinal plant belongs to the Labiatae family that widespread all over Iran. It used as culinary and also in cold and cough treatments in Iran. The aim of present work was to evaluate the effect of different timeframes during the hydrodistillation on essential oil composition, antimicrobial and antioxidant activity. Materials and Methods: The essential oil of Z. clinopodiodes was extracted via hydrodistillation with Clevenger apparatus. The fractions of essential oil were captured at 6 times from the beginning of the distillation: (10, 20, 60, 120, 180 and 240 min). The fractions of essential oil were analyzed by GC/MS and their antibacterial, antifungal and antioxidant activities were studied by Disk - well diffusion and DPPH methods respectively. Results: Six distillation times and whole essential oil were captured during the hydrodistillation. Essential oil yield dropped off significantly during distillation progressed (1.0% for 10 min and 0.025 for 240 min). 1,8 Cineol, Isomenthone, Pulegone, Piperitenone and Citronellic acid were major compounds in fractions and they were affected by distillation times. Pulegone was major compound in all of essential oils. In antioxidant activity assay, whole essential oil was stronger than was stronger than positive control and fractions of essential oil, because of higher levels of Isomenthone, Piperitenone and Citronellic acid. Strongest antimicrobial activity against S. aureus, E. coli and C. albicans was observed from 10 min fraction. Conclusion: Our results indicated that distillation time can create essential oils with specific properties and we can achieve to more efficient essential oil in short times.


2019 ◽  
Vol 9 (3) ◽  
pp. 238-243 ◽  
Author(s):  
Emine Dede ◽  
Nusret Genc ◽  
Mahfuz Elmastas ◽  
Huseyin Aksit ◽  
Ramazan Erenler

Background: Plant in Rhododendron genus that contains phenolic compounds has been used in traditional medicine and revealed considerable biological activities. Objective: Isolation and identification of antioxidant natural products from Rhododendron ungernii. Methods: Rhododendron ungernii Trautv. flowers were collected and dried in shade. The dried flowers were extracted with methanol for 3 days. The solvent was removed by reduced pressure to yield the extract which was subjected to column chromatography (Sephadex LH-20, C18 reversed phase column) to isolate catechin-7-O-glucoside (1), quercetin-3-O-β-galactoside (2), quercetin-3-O- β-xyloside (3), farrerol (4), myricetin (5), and quercetin (6). The structures of isolated compounds were elucidated by spectroscopic methods such as 1D-NMR, 2D-NMR, and LC-TOF/MS. DPPH scavenging effect, ABTS+ scavenging activity, and reducing power (FRAP) were performed for antioxidant assays of isolated natural compounds. Results: Isolated flavonoids displayed the outstanding antioxidant activities. Catechin-7-O-glucoside (1) and quercetin-3-O-β-galactoside (2) (IC50, 3.66 µg/mL) had the most DPPH• scavenging effect among the compounds. The highest ABTS•+ scavenging activity (IC50, 1.41 µg/mL) and reducing power effect (6.05 mmol TE/g comp) were observed for myricetin (5). Conclusion: R. ungernii extract and isolated compounds could be a promising antioxidant for food and pharmaceutical industries.


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