scholarly journals A Comparative Study of Microwave-Assisted and Conventional Heating Methods of the Synthesis of 1-(Naphthalene-1-Yl)-3-(O, M, P-Tolyl)Thioureas, DFT Analysis, Antibacterial Evaluation and Drug-Likeness Assessment

2021 ◽  
Vol 50 (3) ◽  
pp. 743-751
Author(s):  
SUHAILA SAPARI ◽  
EMMA IZZATI ZAKARIAH ◽  
NURUL HIDAYAH ABDUL RAZAK ◽  
INSYIRAH RAMZAN ◽  
MOHD SOFI NUMIN ◽  
...  

New isomers of naphthalene-monothioureas, 3a-3c, were synthesized and characterized by using infrared (IR), 1H and 13 C nuclear magnetic resonance (NMR) and mass spectroscopies (MS). The compounds were obtained from the reaction ofo-, m-, p- toluidine with naphthyl isothiocyanate using conventional reflux and microwave-assisted irradiation methods. Microwave-assisted reaction gave higher yields with reduces the reaction time compared to the conventional heating method. Density Functional Theory (DFT) calculations with 6-31G(d, p) basic set at the B3LYP level is carried out to optimize the structure of isomers and calculate the IR, 1H and 13 C NMR spectra. The DFTB3LYP calculation of FTIR, 1H and 13C NMR spectra of 3a-3c isomers were in accordance with the experimental data. The calculation of frontier molecular orbitals was also selected to study a relationship as a molecular descriptor in antibacterial activity. The isomers were screened for their in vitro antibacterial activity by using Staphylococcus aureus bacteria. Inhibition activity was displayed for compound 3c with the value of inhibition zone 7 ± 0.34 mm at a concentration of 10 μg/mL. All compounds appeared to be in agreement with Lipinski’s rule of five assessments as they adhered to most of the rules that can be preliminarily classified as active drug-like.

2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Huda Misral ◽  
Suhaila Sapari ◽  
Tajudin Rahman ◽  
Nazlina Ibrahim ◽  
Bohari M. Yamin ◽  
...  

Isomers of monothioureas, 2a–2d, derived from the reaction of disubstituted benzoyl isothiocyanate and dibenzylamine were synthesised and characterised by using elementary analysis CHNS and IR, 1H NMR, and 13C NMR spectroscopies. The compounds were screened for their in vitro antibacterial activity by using selected Gram-positive bacteria, and moderate inhibition activity was displayed for compound 2b with the value of inhibition zone 11 ± 0.8 mm at a concentration of 50 mg/ml. The outcomes of Lipinski’s rule of five assessment appeared to be in agreement with all compounds as they adhered to most of the rules, in which they can be preliminarily classified as active drug-like. The frontier molecular orbitals (HOMO and LUMO) for halogen-substituted 3,4-dichloro (2a) and 3,4-difluoro (2b) were also determined by applying the computational method of density functional theory (DFT) to determine their relationship as a molecular descriptor in antibacterial activities. The value of LUMO energy for compound 2b (1.8229 eV) is lower than that of compound 2a (1.8492 eV) which indicates higher antibacterial activities.


2014 ◽  
Vol 56 (4) ◽  
pp. 333-340 ◽  
Author(s):  
Jeferson Junior da Silva ◽  
Cláudio Daniel Cerdeira ◽  
Juliana Moscardini Chavasco ◽  
Ana Beatriz Pugina Cintra ◽  
Carla Brigagão Pacheco da Silva ◽  
...  

Currently multiresistant Staphylococcus aureus is one common cause of infections with high rates of morbidity and mortality worldwide, which directs scientific endeavors in search for novel antimicrobials. In this study, nine extracts from Bidens pilosa (root, stem, flower and leaves) and Annona crassiflora (rind fruit, stem, leaves, seed and pulp) were obtained with ethanol: water (7:3, v/v) and their in vitro antibacterial activity evaluated through both the agar diffusion and broth microdilution methods against 60 Oxacillin Resistant S. aureus (ORSA) strains and against S. aureus ATCC6538. The extracts from B. pilosa and A. crassiflora inhibited the growth of the ORSA isolates in both methods. Leaves of B. pilosa presented mean of the inhibition zone diameters significantly higher than chlorexidine 0.12% against ORSA, and the extracts were more active against S. aureus ATCC (p < 0.05). Parallel, toxicity testing by using MTT method and phytochemical screening were assessed, and three extracts (B. pilosa, root and leaf, and A. crassiflora, seed) did not evidence toxicity. On the other hand, the cytotoxic concentrations (CC50 and CC90) for other extracts ranged from 2.06 to 10.77 mg/mL. The presence of variable alkaloids, flavonoids, tannins and saponins was observed, even though there was a total absence of anthraquinones. Thus, the extracts from the leaves of B. pilosa revealed good anti-ORSA activity and did not exhibit toxicity.


2020 ◽  
Vol 4 (4) ◽  
pp. 287
Author(s):  
Nurliana ◽  
I Bramanti ◽  
ISR Sudarso ◽  
MSH Wahyunigsih ◽  
T Wibawa

Background : This study aims to compare the ability of two medicaments between cresophene and garlic on antibacterial activity of isolate deciduous necrotic teeth.Methods: In vitro test to see the antibacterial activity was carried out on the aerobic and anaerobic bacteria taken straight from the necrotic tooth of pediatric patients (aged 4-7 years old) that treated for endodontics in Pediatric Dental Clinic of RSGMUGM Prof Soedomo. Bacterial identification using the CLSI Standardized Method 2012 and Biochemical identification by Thermo Scientific Rapid System 2010 guideline. In this identification, was founded three species: Prevotella bivia, Serratia marcescens and Clostridium innocum. This test was carried out quantitative measurements to see the inhibition zone of bacterial growth. Whether cresophene has antibacterial potential test results from using an analytical descriptive test that was tabulated.Study group treated with cresophene in a well of 0.7 cm at a dose of 75 μL, garlic extract at a dose of 75 μL divided into five groups with concentrations of 20%, 40%, 60%, 80%, and garlic filtrate. Comparison of the cresophene and garlic effect conducted in vitro by looking at the inhibition zone of the bacterial growth.Results: In all groups, there are inhibitory zones. Cresophene against bacteria Prevotella bivia (54mm), Clostridium innocum (30 mm), Clostridium perfringens (26 mm), Serratia macescens (26 mm), S.mutans (54 mm), while garlic extract against bacteria Prevotella bivia, Clostridium innocum, Clostridium perfringens, S.mutansdonot show againt inhibitory, Serratia macescens (10mm, in concentration of 80 %) and garlic filtrate against bacteria Prevotella bivia (51 mm), Clostridium innocum (28 mm), Clostridium perfringens (46 mm), Serratia marcescens (31 mm), S.mutans (49 mm).Conclusion: Cresophene has a greater inhibition than garlic extract, but it is lower than garlic filtrate.International Journal of Human and Health Sciences Vol. 04 No. 04 October’20 Page : 287-290


Author(s):  
Yori Turu Toja ◽  
Eddy Suprayitno ◽  
Aulanni’am ◽  
Uun Yanuhar

Indonesia has many local plants with potential as herbal antibacterial properties, one of which is the local black fruit of Wandama. The objective of this study is to determine the antibacterial activity of the extract of black fruit seed against A. Hydrophila by in vitro and FTIR by Tilapia. The benefit of this research is to make black fruit seed extract as a natural remedy against tilapia attacked by Aeromonas Hydrophila. The antibacterial activity of black fruit seed extract against A. Hydrophila is investigated in vitro and using FTIR on tilapia in this research. The aim of this study is to establish black fruit seed extract as a natural treatment for tilapia infected with Aeromonas Hydrophila. The disc approach was used to conduct the in vitro research. Agar medium was poured into a sterile petri dish, and 2 drops of bacteria from the liquid medium were uniformly distributed and cooled. On the press, disc paper with black fruit seed extract was put and incubated for 18-24 hours at 35 C. An FTS 1000 version spectrophotometer system was used for the FTIR test. For the FT-IR study, a fraction of dried black fruit seeds was used. For clear preparation, 100 mg of dry extract is condensed in KBr pellets. A specimen of loaded black fruit seed samples was analyzed using FT-IR spectroscopy with a scanning range of 400-4000 cm-1 and a resolution of 4 cm-1. The results showed that the ethyl acetate fraction produced an inhibition zone (13.65 mm), the water fraction produced an inhibition zone (11.21 mm), and the n-hexane fraction produced the weakest inhibition zone (11.21 mm) (5.31mm). The concentration test results from 125 ppm, 250 ppm, 500 ppm and 1000 ppm obtained a large inhibition zone at a concentration of 1000 ppm with an inhibition zone area of 11.43 + 0.02. The absorbance value of black fruit seed extract in ethyl acetate solvent at 3430 cm-1 revealed the absorption band with the strongest vibration of the hydroxylate (-OH) functional group, according to FTIR research. Final thoughts with an average value of 13.65 + 0.06, black fruit seed extract using ethyl acetate can inhibit A. Hydrophila bacteria.


2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Faisal GG ◽  
Zakaria SM ◽  
Najmuldeen GF

Introduction: Currently, researchers are aiming to explore herbal plants to replace synthetic drugs because herbal plants contain high active compounds and fewer side effects. Our study was done to determine the antibacterial activity of Eurycoma longifolia Jack (E. longifolia) root using ethanol based extract. Methods: Five types of pathogenic bacterial strains were used; Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa). Disc diffusion assay and Minimum Inhibitory Concentration (MIC) tests were used to determine the inhibition zone and turbidity of suspension which reflects the antibacterial activity of the extract. Results: The ethanolic extract of E. longifolia Jack root extract showed positive results against Gram-positive bacteria (S. aureus and B. cereus) and Gramnegative (S. typhi). B.cereus and S.typhi showed inhibition zone values of 11.76mm and 14.33mm at the extract concentration of 150mg/ml that were higher than the positive control values (9.00, 12.67mm) respectively. However, E. coli and P. aeruginosa did not show any inhibition by the ethanol-based extract. Conclusion: From the results we can conclude that E.Longifolia root extract possesses antibacterial activity that can be further explored to produce new medicinal products.


2017 ◽  
Vol 1 (01) ◽  
pp. 22
Author(s):  
Josi Saraswati ◽  
Annisa Septalita ◽  
Arini Bovita. N

Introduction: Lactobacillus acidophilus is one of the bacteria causes dental caries. The previous study has shown that Kaempferia galanga extract has a potential to inhibit the growth of Lactobacillus acidophilus.Objective: To determine the antibacterial effect of Kaempferia galanga extract to Lactobacillus acidophilus.Methods:Kaempferia galanga is extracted in 3 different solvents:dichlormethane, ethanol, and aquades. For each solvent, 0.2 μl Kaempferia galanga extractdroped into 6 mm steril paper dics. 0.1 ml Lactobacillus acidophilus inoculated on MRS agar. Each disc contains extract were impragnated into the agar media, then incubated at 370C for 24 hours, and inhibition zone measured.Results: Mean scores of Kaempferia galanga extract in 3 different solvents are: Kaempferia galanga (dichlormethane) is 1.6400; Kaempferia galanga (ethanol) is 1.7440; Kaempferia galanga extract is 1.6600; boiled Kaempferia galanga is 1.7000. Using Mann-Whitney Test, the results are: negative controls have no inhibition effect on Lactobacillus acidophilus compaired to Kaempferia galanga extract, comparation of those 4 Kaempferia galangal treatments shows no significant difference, those 4 Kaempferia galanga treatments compaired to erythromycin antibacterial effect shows significant difference, otherwise 4 Kaempferia galanga treatments compaired to penicillin shows no significant difference except Kaempferia galanga (ethanol).Conclusions: Kaempferia galanga extract can kill Lactobacillus acidophilus. Inhibition effect of Kaempferia galanga extract has no significant difference to penicillin but lower inhibition effect than erythromycin. The Kaempferia galanga extracts showed better antibacterial activity than penicillin.


2021 ◽  
pp. 2427-2433
Author(s):  
Tipwadee Prapaiwong ◽  
Wuttikorn Srakaew ◽  
Chalong Wachirapakorn ◽  
Chaiwat Jarassaeng

Background and Aim: Hydrolyzable tannins are an important group of secondary plant metabolites, which are known for antimicrobial activity. This study aimed to assess the efficiency with which a hydrolyzable tannin extract from sweet chestnut wood (Castanea sativa Mill.) could inhibit mastitis-causing bacteria in vitro. Materials and Methods: The negative control used was sterile water, and the positive controls were penicillin and gentamicin. The treatments included five concentrations of hydrolyzable tannins (63, 190, 313, 630, and 940 mg/mL). In cows with subclinical mastitis, the bacteria causing the disease were isolated and identified. Then, the antibacterial activity of the hydrolyzable tannin extract was assessed by the disk diffusion method, by determining the minimum inhibitory concentration (MIC) and by determining the minimum bactericidal concentration (MBC). Results: Penicillin inhibited (p<0.01) the growth of Staphylococcus aureus, Streptococcus uberis, and Pseudomonas aeruginosa but could not inhibit (p>0.05) the growth of Streptococcus agalactiae, Escherichia coli, and Klebsiella pneumoniae. However, gentamicin and hydrolyzable tannins could inhibit (p<0.01) all isolated bacteria. Increasing the concentration of hydrolyzable tannin extract resulted in a quadratic increase in the inhibition zone diameter of S. aureus and S. agalactiae and a linear increase in the inhibition zone diameter of E. coli, K. pneumoniae, and P. aeruginosa. In addition, 630 and 940 mg/mL of hydrolyzable tannin extract showed the highest antibacterial activity against S. agalactiae and E. coli (p<0.01), while 940 mg/mL concentration had the highest antibacterial activity against K. pneumoniae (p<0.01). The MIC and MBC of the extract were 27.3-190 mg/mL and 58.8-235 mg/mL, respectively, with the MBC: MIC ratio being 2:1. Conclusion: The antimicrobial activity of the hydrolyzable tannin extract against subclinical mastitis bacteria was comparable to the antibiotics (positive controls) at concentrations over 630 mg/mL. Although these in vitro findings are promising, further research is needed to determine whether hydrolyzable tannins could be used to control or prevent subclinical mastitis in dairy cows.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Eshetu Gadisa ◽  
Hydar Usman

Background. Emerging of multidrug-resistant bacteria can compromise the effectiveness of antibiotics used to treat skin infections. Those bacteria imposed public health problems and questioning medical care in the 21st century. In this circumstance, essential oils of medicinal plants origin are supreme sources of structural and functionally divergent compounds, which inhibited the growth of common wound colonizing MRSA and ESBL producing P. aeruginosa. The aim of this study was to evaluate the combined antibacterial activity of essential oils extracted from Rumex abyssinicus, Cucumis pustulatus, and Discopodium penninervium against multidrug-resistant (MDR) isolates of skin ulcers. Methods. Essential oils (EOs) were extracted from aerial parts of R. abyssinicus, C. pustulatus, and D. penninervium with steam distillation. A mixture of each oil (1 : 1) was adsorbed to a disc and placed on Mueller Hinton Agar. Then, minimum zone of inhibition and bactericidal concentration of EOs was measured after incubeted for 18–24 hours at 37 °C. Their combined antibacterial effect was determined by the fractional inhibitory concentration index. Results. The antibacterial activity of mixed oil varied in their doses and bacteria species, of which a mixture of essential oil of R. abyssinicus and D. penninervium had inhibition zone (32 mm); its MIC and MBC values range from 1-2 μl/ml against MRSA. It had an inhibition zone (36 mm), MIC value 4 μl/ml, and MBC (8 μl/ml) against ESBL producing P. aeruginosa, whereas combined effects of R. abyssinicus and C. pustulatus had MIC values ranging from 2–8 μl/ml for E. coli and K. pneumoniae and 2 μl/ml for MRSA. There was a strong synergistic effect between R. abyssinicus and D. penninervium and promising antibacterial effect more specifically on MRSA and P. aeruginosa. Conclusion. This in vitro study of the combined effect of EOs has significant antibacterial activity on wound colonizing bacteria and reduces delaying wound healing as that of modern drugs tested in parallel. Hence, further structural elucidation of active compounds helps us to properly design or synthesis of topical antibiotics for wound care.


2020 ◽  
Vol 14 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Lisda Damayanti ◽  
Ida Ayu Evaangelina ◽  
Avi Laviana ◽  
Yetty Herdiyati ◽  
Dikdik Kurnia

Background: Caries and periodontitis are dental diseases caused by bacteria of S. sanguinis, S. mutans, and E. faecalis with three main etiological factors of the host, substrate, and time. Objective: This study proposed to investigate the antibacterial effects of Buah Merah (Pandanus conoideus Lam.) against oral bacteria of E.faecalis, S. mutans, and S. sanguinis. Materials and Methods: The Buah Merah was extracted with different solvents to yield n-hexane, ethyl acetate, methanol, and H2O extracts. The concentrations of single and mixture extracts were adjusted for antibacterial assay against bacteria of E. faecalis, S. mutans, and S. sanguinis strains through agar well diffusion assay with chlorhexidine, fosfomycin, and quercetin used as positive controls. Results: The ethyl acetate extract showed highest antibacterial activity against three oral bacterial of E. faecalis, S. mutans, and S. sanguinis with inhibition zones values of 9.3, 12.3, and 17.9 mm at 40%, respectively, together with their MIC and MBC values of 1250 & 2500, 0.312 & 0.625, and 0.312 & 0.625 ppm, respectively. For the formulation of extracts, combinations samples test gave various effects to different bacteria, with the best activity showed by methanol-ethyl acetate (M-Ea) extracts against S. mutans with an inhibition zone of 16.25 mm at 40 ppm. The strong and synergistic effect of methanol extract against S. mutans was supported by inhibition zones of the formulation of methanol extract-fosfomycin which showed an inhibition zone of 25.9 mm at 10 ppm. Conclusion: The extracts of Buah Merah demonstrated antibacterial activity against oral bacteria of E. faecalis, S. mutans, and S. sanguinis and gave important information for further in vivo clinical studies to determine the exact dosages and its effectiveness in practical application. These results prove the antimicrobial effects of Buah Merah extracts as alternative natural drugs with synergistic effects of active constituents.


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