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This study aimed to evaluate 2-(N-((2′-(2H-tetrazole-5-yl)-[1,1′-biphenyl]-4yl)-methyl)-pentanamido)-3-methyl butanoic acid-based ester derivatives as a new class of angiotensin-II receptor antagonists. For this purpose, a series of compounds were synthesized using a variety of phenols. Their chemical characterization was established by FTIR, 1HNMR, and 13CNMR techniques. The biological activities including antioxidant potentials using the DPPH assay, the antihypertensive assay, the urease enzyme inhibition assay, and the antibacterial assay using agar well diffusion methods were performed. All the new compounds showed significant free radical scavenging potentials more than the parent drug while retaining antihypertensive potentials along with urease inhibition properties. However, the AV2 test compound was found to be the most potent against hypertension. Most of the synthesized analogs showed urease inhibitory actions. Molecular docking studies were performed for all the active analogs to decode the binding detail of the ligands with receptors of the enzyme's active site. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is a major public brain condition that has resulted in many deaths, as revealed by the World Health Organization (WHO). Conventional Alzheimer's treatments such as chemotherapy, surgery, and radiotherapy are not very effective and are usually associated with several adverse effects. Therefore, it is necessary to find a new therapeutic approach that completely treats Alzheimer's disease without many side effects. In this research project, we report the synthesis and biological activities of some new thiazole-bearing sulfonamide analogs (1–21) as potent anti-Alzheimer's agents. Suitable characterization techniques were employed, and the density functional theory (DFT) computational approach, as well as in-silico molecular modeling, has been employed to assess the electronic properties and anti-Alzheimer's potency of the analogs. All analogs exhibited a varied degree of inhibitory potential, but analog 1 was found to have excellent potency (IC50 = 0.10 ± 0.05 µM for AChE) and (IC50 = 0.20 ± 0.050 µM for BuChE) as compared to the reference drug donepezil (IC50 = 2.16 ± 0.12 µM and 4.5 ± 0.11 µM). The structure-activity relationship was established, and it mainly depends upon the nature, position, number, and electron-donating/-withdrawing effects of the substituent/s on the phenyl rings. [ABSTRACT FROM AUTHOR]

Triazole-based thiosemicarbazone derivatives (6a–u) were synthesized then characterized by spectroscopic techniques, such as 1HNMR and 13CNMR and HRMS (ESI). Newly synthesized derivatives were screened in vitro for inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. All derivatives (except 6c and 6d, which were found to be completely inactive) demonstrated moderate to good inhibitory effects ranging from 0.10 ± 0.050 to 12.20 ± 0.30 µM (for AChE) and 0.20 ± 0.10 to 14.10 ± 0.40 µM (for BuChE). The analogue 6i (IC50 = 0.10 ± 0.050 for AChE and IC50 = 0.20 ± 0.050 µM for BuChE), which had di-substitutions (2-nitro, 3-hydroxy groups) at ring B and tri-substitutions (2-nitro, 4,5-dichloro groups) at ring C, and analogue 6b (IC50 = 0.20 ± 0.10 µM for AChE and IC50 = 0.30 ± 0.10 µM for BuChE), which had di-Cl at 4,5, -NO2 groups at 2-position of phenyl ring B and hydroxy group at ortho-position of phenyl ring C, emerged as the most potent inhibitors of both targeted enzymes (AChE and BuChE) among the current series. A structure-activity relationship (SAR) was developed based on nature, position, number, electron donating/withdrawing effects of substitution/s on phenyl rings. Molecular docking studies were used to describe binding interactions of the most active inhibitors with active sites of AChE and BuChE. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) has been associated with the hallmark features of cholinergic dysfunction, amyloid beta (Aβ) aggregation and impaired synaptic transmission, which makes the associated proteins, such as β-site amyloid precursor protein cleaving enzyme 1 (BACE I), acetylcholine esterase (AChE) and synapsin I, II and III, major targets for therapeutic intervention. The present study investigated the therapeutic potential of three major phytochemicals of Rosmarinus officinalis, ursolic acid (UA), rosmarinic acid (RA) and carnosic acid (CA), based on their binding affinity with AD-associated proteins. Detailed docking studies were conducted using AutoDock vina followed by molecular dynamic (MD) simulations using Amber 20. The docking analysis of the selected molecules showed the binding energies of their interaction with the target proteins, while MD simulations comprising root mean square deviation (RMSD), root mean square fluctuation (RMSF) and molecular mechanics/generalized born surface area (MM/GBSA) binding free energy calculations were carried out to check the stability of bound complexes. The drug likeness and the pharmacokinetic properties of the selected molecules were also checked through the Lipinski filter and ADMETSAR analysis. All these bioactive compounds demonstrated strong binding affinity with AChE, BACE1 and synapsin I, II and III. The results showed UA and RA to be potential inhibitors of AChE and BACE1, exhibiting binding energies comparable to those of donepezil, used as a positive control. The drug likeness and pharmacokinetic properties of these compounds also demonstrated drug-like characteristics, indicating the need for further in vitro and in vivo investigations to ascertain their therapeutic potential for AD. [ABSTRACT FROM AUTHOR]

The rapid development of resistance by ureolytic bacteria which are involved in various life-threatening conditions such as gastric and duodenal cancer has induced the need to develop a new line of therapy which has anti-urease activity. A series of pyridine carboxamide and carbothioamide derivatives which also have some novel structures were synthesized via condensation reaction and investigated against urease for their inhibitory action. Among the series, 5-chloropyridine-2 yl-methylene hydrazine carbothioamide (Rx-6) and pyridine 2-yl-methylene hydrazine carboxamide (Rx-7) IC50 = 1.07 ± 0.043 µM, 2.18 ± 0.058 µM both possessed significant activity. Furthermore, molecular docking and kinetic studies were performed for the most potent inhibitors to demonstrate the binding mode of the active pyridine carbothioamide with the enzyme urease and its mode of interaction. The ADME profile also showed that all the synthesized molecules present oral bioavailability and high GI absorption. [ABSTRACT FROM AUTHOR]

Background: Dihydrofolate reductase (DHFR) is an important target for antimetabolite class of antimicrobials because it participates in purine synthesis. 2-mercaptobenzimidazole (2MBI) has similar structural features as purine nucleotides. Given that benzimidazole and similar heteroaromatics have been broadly examined for their anticancer potential, so, we hereby report the design, synthesis and biological studies (i.e. antimicrobial and anticancer studies) of 2MBI derivatives. Methodology: The antimicrobial activity of synthesized 2MBI derivatives were evaluated against Gram positive and Gram negative bacterial species as well as fungal species by tube dilution technique whereas their anticancer activity was assessed against human colorectal carcinoma cell line (HCT116) by Sulforhodamine B (SRB) assay. They were also structurally characterized by IR, NMR, MS and elemental analyses. Results, discussion and conclusion: The antimicrobial activity findings revealed that compound N1 ( MICbs,st,ca = 1.27, 2.54, 1.27 μM), N8 ( MICec= 1.43 μM), N22 ( MICkp,an= 2.60 μM), N23 and N25 ( MICsa= 2.65 μM) exhibited significant antimicrobial effects against tested strains, i.e. Gram-positive, Gram-negative (bacterial) and fungal strains. The anticancer screening results demonstrated that compounds N9, N18 ( IC50 = 5.85, 4.53 μM) were the most potent compounds against cancer cell line (HCT116) even more than 5-FU, the standard drug ( IC50 = 9.99 μM). [ABSTRACT FROM AUTHOR]

A new series of acetamide derivatives containing 1,2,4-triazole and azinane moieties has been synthesized and characterized using 1 H NMR, 13 C NMR, IR, and EI-MS spectroscopic analysis. The intermediate triazole was synthesized through a sequential synthesis of carboxylate and carbohydrazide. The bovine serum albumin (BSA) binding of the newly synthesized 1,2,4-triazole derivatives was evaluated along with thermodynamics, site-selective binding, and synchronous study. The results obtained by BSA binding as well as thermodynamic studies justify that all the compounds show spontaneous interaction with BSA and could be effectively distributed and eliminated from the body. Therefore, the triazole-based analogs might be a useful strategy for designing new drug systems. [ABSTRACT FROM AUTHOR]

The present study investigates the neuroprotective effects of Foeniculum vulgare seeds in a lead (Pb)-induced brain neurotoxicity mice model. The dried seeds extract of Foeniculum vulgare was prepared with different concentrations of organic solvents (ethanol, methanol, n-hexane). The in vitro antioxidant activity of Foeniculum vulgare seed extracts was assessed through DPPH assay and the chemical composition of the extracts was determined by high-resolution 1H NMR spectroscopy. The age-matched male Balb/c mice (divided into 9 groups) were administered with 0.1% Pb and 75% and 100% ethanol extracts of Foeniculum vulgare seeds at a dose of 200 mg/kg/day and 20 mg/kg/day. The maximum antioxidant activity was found for 75% ethanol extract, followed by 100% ethanol extract. Gene expression levels of oxidative stress markers (SOD1 and Prdx6) and the three isoforms of APP (APP common, 770 and 695), in the cortex and hippocampus of the treated and the control groups were measured. Significant increase in APP 770 expression level while a substantial decrease was observed for SOD1, Prdx6 and APP 695 expression in Pb-treated groups. Interestingly, the deranged expression levels were significantly normalized by the treatment with ethanol extracts of Foeniculum vulgare seeds (specifically at dose of 200 mg/kg/day). Furthermore, the Pb-induced morphological deterioration of cortical neurons was significantly improved by the ethanol extracts of Foeniculum vulgare seeds. In conclusion, the present findings highlight the promising therapeutic potential of Foeniculum vulgare to minimize neuronal toxicity by normalizing the expression levels of APP isoforms and oxidative stress markers. [ABSTRACT FROM AUTHOR]

The present study comprises the synthesis of a new series of sulfonamides derived from 4-methoxyphenethylamine (1). The synthesis was initiated by the reaction of 1 with 4-methylbenzenesulfonyl chloride (2) in aqueous sodium carbonate solution at pH 9 to yield N-(4-methoxyphenethyl)-4-methylbenzensulfonamide (3).This parent molecule 3 was subsequently treated with various alkyl/aralkyl halides, (4a-j), using N,N-dimethylformamide (DMF) as solvent and LiH as activator to produce a series of new N-(4-methoxyphenethyl)-N-(substituted)-4-methylbenzenesulfonamides (5a-j). The structural characterization of these derivatives was carried out by spectroscopic techniques like IR, ¹H-NMR, and 13C-NMR. The elemental analysis data was also coherent with spectral data of these molecules. The inhibitory effects on acetylcholinesterase and DPPH were evaluated and it was observed that N-(4-Methoxyphenethyl)-4-methyl- N-(2-propyl)benzensulfonamide (5c) showed acetylcholinesterase inhibitory activity 0.075 ± 0.001 (IC50 0.075 ± 0.001 µM) comparable to Neostigmine methylsulfate (IC50 2.038 ± 0.039 µM). The docking studies of synthesized ligands 5a-j were also carried out against acetylcholinesterase (PDBID 4PQE) to compare the binding affinities with IC50 values. The kinetic mechanism analyzed by Lineweaver-Burk plots demonstrated that compound (5c) inhibits the acetylcholinesterase competitively to form an enzyme inhibitor complex. The inhibition constants Ki calculated from Dixon plots for compound (5c) is 2.5 µM. It was also found from kinetic analysis that derivative 5c irreversible enzyme inhibitor complex. It is proposed on the basis of our investigation that title compound 5c may serve as lead structure for the design of more potent acetylcholinesterase inhibitors. [ABSTRACT FROM AUTHOR]

Flavokawain B (1) is a natural chalcone extracted from the roots of Piper methysticum, and has been proven to be a potential cytotoxic compound. Using the partial structure of flavokawain B (FKB), about 23 analogs have been synthesized. Among them, compounds 8, 13 and 23 were found in new FKB derivatives. All compounds were evaluated for their cytotoxic properties against two breast cancer cell lines, MCF-7 and MDA-MB-231, thus establishing the structure–activity relationship. The FKB derivatives 16 (IC50 = 6.50 ± 0.40 and 4.12 ± 0.20 μg/mL), 15 (IC50 = 5.50 ± 0.35 and 6.50 ± 1.40 μg/mL) and 13 (IC50 = 7.12 ± 0.80 and 4.04 ± 0.30 μg/mL) exhibited potential cytotoxic effects on the MCF-7 and MDA-MB-231 cell lines. However, the methoxy group substituted in position three and four in compound 2 (IC50 = 8.90 ± 0.60 and 6.80 ± 0.35 μg/mL) and 22 (IC50 = 8.80 ± 0.35 and 14.16 ± 1.10 μg/mL) exhibited good cytotoxicity. The lead compound FKB (1) showed potential cytotoxicity (IC50 = 7.70 ± 0.30 and 5.90 ± 0.30 μg/mL) against two proposed breast cancer cell lines. It is evident that the FKB skeleton is unique for anticancer agents, additionally, the presence of halogens (Cl and F) in position 2 and 3 also improved the cytotoxicity in FKB series. These findings could help to improve the future drug discovery process to treat breast cancer. A molecular dynamics study of active compounds revealed stable interactions within the active site of Janus kinase. The structures of all compounds were determined by 1H-NMR, EI-MS, IR and UV and X-ray crystallographic spectroscopy techniques. [ABSTRACT FROM AUTHOR]

The current research effort embodies the assessment of anti-bacterial potential of some N-substituted sulfonamides. The synthetic methodology was triggered by reaction of 2,4- dimethylaniline (1) with benzenesulfonyl chloride (2) at pH 9-10 in aqueous sodium carbonate (10 %) to generate N-(2,4-dimethylphenyl)benzenesulfonamide (3) which was further treated with different aralkylated halides (4a-e) in polar aprotic medium; N, N-dimethylformamide (DMF) and lithium hydride (LiH) which acts as base under stirring at room temperature for 3 hours to afford Naralkylated- N-(2,4-dimethylphenyl)benzenesulfonamides (5a-e). The proposed structures of sulfonamides were explicated via contemporary spectral methods e.g. IR, 1H-NMR, 13C -NMR and EIMS. Moreover, they were analyzed against different Gram (-) and (+) bacterial strains to unravel their inhibitory potential. The amalgamation of sulfonamide moiety with different aralkyl halides resulted in good anti-bacterial activity compared to standard; Ciprofloxacin. N-2-bromobenzyl-N- (2,4-dimethylphenyl)benzenesulfonamide (5d) and N-2-phenylpropyl-N-(2,4- dimethylphenyl)benzenesulfonamide (5b) contributed significantly which may be attributed to the successful and fruitful N-insertion of 2-bromobenzyl and 2-phenylpropyl moieties on parent sulfonamide. [ABSTRACT FROM AUTHOR]

The objective of this study is to provide a mechanistic insight into solubility enhancement and dissolution of acyclovir (ACY) by polyethylene glycol20000 (PEG20000). Materials and Methods: Solid dispersions with differing ratios of drug (ACY) and carrier (PEG20000) were prepared and evaluated by phase solubility, in vitro release studies, kinetic analysis, in situ perfusion, and in vitro permeation studies. Solid state characterization was also done by Powder X‑Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared spectroscopy (FT-IR) analysis and surface morphology was assessed by Polarizing Microscopic Image (PMI) analysis, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and Nuclear Magnetic Resonance (NMR) analysis. Results: Thermodynamic parameters proved the solubilization effect of carrier. The aqueous solubility and dissolution of ACY were increased in all samples. Formation of solid solution, crystallinity reduction, and absence of interaction between drug and carrier was proved by XRD, DSC, and FTIR analysis. The particle size reduction and change in surface morphology were confirmed by SEM and AFM and analysis. The permeation coefficient and amount of drug diffused was higher in samples as compared to ACY. The stability was high in dispersions, and it was proved by NMR analysis. Conclusion: The mechanical insights into the enhancement of solubility and dissolution could be used as a platform to improve the aqueous solubility for other poor water soluble drugs. [ABSTRACT FROM AUTHOR]

The aim of the study was to find out whether eliminating intraoperative intermaxillary fixation from the management of mandibular fractures has any bearing on treatment outcomes. A retrospective study was carried out on 53 mandibular fractures treated at Margalla Institute of Health Sciences and its affiliated hospitals from June 2010 to December 2014. Successful bone healing, occlusion and complications were assessed in mandibular fractures treated with open reduction and internal fixation and without the use of intraoperative intermaxillary fixation. Minor wound dehiscence was seen in 7 patients. 3 patients required hardware removal due to subsequent hardware failure; however no case of nonunion was seen. Clinically significant malocclusion (Moderate: Grade 2) was seen in only one patient after 3 months. There were negligible and comparable number of postoperative complications. It was concluded 'hand holding' of the mandibular fractures as an alternative to the more traditional IMF/MMF through various means, a reliable and predictable way of fixation of mandibular fractures. [ABSTRACT FROM AUTHOR]

An effective and eco-friendly method for the bis(indolyl)methanes synthesis has been developed. A successive methodology involving sodium iodate/sodium hydrogen sulfite catalyzed reaction of indole with many aldehydes gave the resultant bis-indol in good yield. This method offers synthetically inexpensive alternate to the previously developed procedures for the bis-indol synthesis. The use of a low-cost and straightforwardly accessible catalyst, improved yields and a simple reaction process are the salient features of the current method. [ABSTRACT FROM AUTHOR]

The anti-inflammatory drug predinisolone (1) was reduced to 20β-hydroxyprednisolone (2) by the marine endophytic fungus Penicilium lapidosum isolated from an alga. The structural elucidation of 2 was achieved by 1D- and 2D-NMR, MS, IR data. Although, 2 is a known compound previously obtained through microbial transformation, the data provided failed to prove the C20 stereochemistry. To solve this issue, DFT and TD-DFT calculations have been carried out at the B3LYP/6-31+G (d,p) level of theory in gas and solvent phase. The absolute configuration of C20 was eventually assigned by combining experimental and calculated electronic circular dichroism spectra and 3JHH chemical coupling constants. [ABSTRACT FROM AUTHOR]

Phenoxyacetohydrazide Schiff base analogs 1–28 have been synthesized and their in vitro β-glucouoronidase inhibition potential studied. Compounds 1 (IC50 = 9.20 ± 0.32 μM), 5 (IC50 = 9.47 ± 0.16 μM), 7 (IC50 = 14.7 ± 0.19 μM), 8 (IC50 = 15.4 ± 1.56 μM), 11 (IC50 = 19.6 ± 0.62 μM), 12 (IC50 = 30.7 ± 1.49 μM), 15 (IC50 = 12.0 ± 0.16 μM), 21 (IC50 = 13.7 ± 0.40 μM) and 22 (IC50 = 22.0 ± 0.14 μM) showed promising β-glucuronidase inhibition activity, better than the standard (D-saccharic acid-1,4-lactone, IC50 = 48.4 ± 1.25 μM). [ABSTRACT FROM AUTHOR]

The most common impacted tooth is mandibular third molar and knowledge and assessment of its angulation pattern, position and depth in mandibular bone helps in better treatment planning and management of patients. The objective of this study was to enlist the frequency of dental caries and pericoronitis associated with different patterns of impacted mandibular third molars in different age groups and genders. A total of 250 patients with 393 impacted mandibular third molars seen in the Department of Oral and Maxillofacial Surgery, Punjab Dental Hospital, Lahore from October 2012 to March 2013 were included in the study. The age range of these patients was of 20 to 65 years. Patients were assessed by history, clinical and radiographic examination. Patterns of mandibular third molar impactions were assessed by using classification systems developed by Winter and Pell and Gregory on periapical radiographs. Pericoronitis was assessed by patient's history and clinical evaluation of mucosa surrounding the impacted mandibular third molars. Dental caries was assessed by clinical and radiographic evaluation. The most frequent pattern of impaction was mesioangular (37.6%), with Class II ramus relationship (53.2%) and Position A depth (62.8%). Dental caries was seen in 38.53% of patients mostly associated with mesioangular, Position A, Class I molars. Pericoronitis was seen in 29.36% of patients mostly associated with distoangular, Position A or B, Class II molars. It was concluded that the patients having third molars with the unfavourable angulations, patterns and positions could be considered as the candidates for prophylactic removal of impacted mandibular third molars to prevent dental caries or pericoronitis. Moreover, early diagnosis of percoronitis and dental caries and proper management of third molar is necessary to prevent further consequences. [ABSTRACT FROM AUTHOR]

Hispidin oligomers are styrylpyrone pigments isolated from the medicinal fungi Inonotus xeranticus and Phellinus linteus. They exhibit diverse biological activities and strong free radical scavenging activity. To rationalize the antioxidant activity of a series of four hispidin oligomers and determine the favored mechanism involved in free radical scavenging, DFT calculations were carried out at the B3P86/6-31+G (d, p) level of theory in gas and solvent. The results showed that bond dissociation enthalpies of OH groups of hispidin oligomers (ArOH) and spin density delocalization of related radicals (ArÓ) are the appropriate parameters to clarify the differences between the observed antioxidant activities for the four oligomers. The effect of the number of hydroxyl groups and presence of a catechol moiety conjugated to a double bond on the antioxidant activity were determined. Thermodynamic and kinetic studies showed that the PC-ET mechanism is the main mechanism involved in free radical scavenging. The spin density distribution over phenoxyl radicals allows a better understanding of the hispidin oligomers formation. [ABSTRACT FROM AUTHOR]

It is a cross sectional study conducted in a tertiary care hospital. Patients of condylar fracture reporting to oral & maxillofacial trauma center were evaluated radiographically (OPG, PA view and Lateral Oblique View) as well as clinically to record the etiology of mandibular condylar fractures. A total of 70 patients of 3 to 45 years of age were included in this study. The frequency of condylar fractures was higher in male of all age groups except for 11-20 years where females comprised of 55.5% of the cases. Among males, the highest frequency of fractures occurred in the third decade of life. Regarding the etiology of mandible condylar fractures, falls (45.71%) and RTA (40%) were found to be the most predominant causative factors, followed by industrial and occupational accidents (6%), Sports injuries (6%) and assault injuries (3%). Falls were the etiologic factor in most of the cases which explains the association of falls with the mechanism of condylar injury. Road traffic accidents were the second common cause. Type 2 fractures which are low neck fractures with displacement were seen to be the most frequent. [ABSTRACT FROM AUTHOR]

Temporomandibular joint (TMJ) ankylosis is a very distressing structural condition that causes severe facial disfigurement leading to pathopsychological stress. Impairment of speech, difficulty with mastication, rampant caries, poor oral hygiene, disturbances of facial growth and severely compromised airway are the leading consequences of TMJ ankylosis. Surgical intervention is the widely accepted treatment modality of TMJ ankylosis. Current study was performed on 30 patients for three years (2009-2012) department of Oral and Maxillofacial Surgery, Children Hospital and Department of Nuclear Medicine, Shaukat Khanum Memorial Cancer Hospital and Research Center, Lahore and costochondral graft was used to treat mandibular ankylosis. 21 (70%) patients were males and were divided into age groups of 2-5, 6-12 and 13-18 years. Regarding the side of mandible involved in male patients, unilateral ankylosis was found in 15(50%) and bilateral ankylosis were found in 6(20%) patients. Similarly in female patients, unilateral ankylosis was found in 7(23%) and bilateral ankylosis was seen in 2(7%) patients. Regarding post operative monitoring of graft, bone scintigraphy was performed one week after the surgery and then after 12 weeks and 16 weeks to assess the viability and uptake of costochondral graft. Tc.99m MDP bone scan was performed in supine position with intravenous administration of 370MBq one week after the placement of graft. Results showed that out of 30 patients, CCG graft was viable in 28(93%) while it was non viable in 2(7%) patients. [ABSTRACT FROM AUTHOR]

According to the latest report released by the World Health Organization, bacterial resistance to well-known and widely available antibacterial drugs has become a significant and severe global health concern and a grim challenge to tackle in order to cure infections associated with multidrug-resistant pathogenic microorganisms efficiently. Consequently, various strategies have been orchestrated to cure the severe complications related to multidrug-resistant bacteria effectively. Some approaches involved the retardation of biofilm formation and multidrug-resistance pumps in bacteria as well as the discovery of new antimicrobial agents demonstrating different mechanisms of action. In this regard, natural products namely alkaloids, terpenoids, steroids, anthraquinone, flavonoids, saponins, tannins, etc., have been suggested to tackle the multidrug-resistant bacterial strains owing to their versatile pharmacological effects. Amongst these, flavonoids, also known as polyphenolic compounds, have been widely evaluated for their antibacterial property due to their tendency to retard the growth of a wide range of pathogenic microorganisms, including multidrug-resistant bacteria. The hydroxylation of C5, C7, C3′, and C4′; and geranylation or prenylation at C6 have been extensively studied to increase bacterial inhibition of flavonoids. On the other hand, methoxylation at C3′ and C5 has been reported to decrease flavonoids' antibacterial action. Hence, the latest information on the antibacterial activity of flavonoids is summarized in this review, with particular attention to the structure–activity relationship of this broad class of natural compounds to discover safe and potent antibacterial agents as natural products. [ABSTRACT FROM AUTHOR]

Dye removal through photocatalytic degradation employing nanomaterials as catalysts is a growing research area. In current studies, photocatalytic alizarin red (AR) dye degradation has been investigated by designing a series of Cr based manganese oxide nanomaterials (MH1–MH5). Synthesized nanomaterials were characterized by powder X-ray diffraction, scanning electron microscopy/energy dispersive x-ray, Brunauer–Emmett–Teller, and photoluminescence techniques and were utilized for photocatalytic AR dye degradation under UV light. AR dye degradation was monitored by UV–visible spectroscopy and percent degradation was studied for the effect of time, catalyst dose, different dye concentrations, and different pH values of dye solution. All the catalysts have shown more than 80% dye degradation exhibiting good catalytic efficiencies for dye removal. The catalytic pathway was analyzed by applying the kinetic model. A pseudo second-order model was found the best fitted kinetic model indicating a chemically-rate controlled mechanism. Values of constant R2 for all the factors studied were close to unity depicting a good correlation between experimental data. [ABSTRACT FROM AUTHOR]

Digestive enzymes and free radical inhibitors are used to prevent complications resulting from diabetes. Entadaspiralis (family Leguminosae), which is a well-known medicinal plant in herbal medicine due to its various traditional and medicinal applications, was studied. Crude extracts were successively obtained from the stem bark using petroleum ether, chloroform and methanol as extracting solvents. The antioxidant activity of all the extracts, fractions and isolated compounds were estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene and 2,2′-azinobis(-3-ethylbenzothiazine-6-sulfonic acid) (ABTS) assays, while digestive enzymes inhibitory activity was assessed using α-amylase and α-glucosidase inhibitory methods. Structure elucidation of pure compounds was achieved through different spectroscopic analysis methods. Fractionation and purification of the most active methanol extract resulted in the isolation of a ferulic ester namely; (e)-hexyl 3-(4-hydroxy-3-methoxyphenyl) acrylate (FEQ-2) together with five known phenolic constituents, identified as kaempferol (FEQ-3), 5,4′-dihydroxy-3,7,3′-trimethoxyflavone (FEQ-2), gallic acid (FEQ-5), (+)-catechin (FEQ-7) and (−)-epicatechin (FEQ-8). FEQ-5 exhibited the strongest antioxidant and enzyme inhibitory activities followed by FEQ-3 and FEQ-4. FEQ-2 also displayed potent free radical scavenging activity with IC50 values of 13.79 ± 2.13 (DPPH) and 4.69 ± 1.25 (ABTS) µg/mL, respectively. All other compounds were found active either against free radicals or digestive enzymes. [ABSTRACT FROM AUTHOR]