In vitro Screening for Antioxidant and Antimicrobial Properties of 3,5-Bis(E-thienylmethylene) piperidin-4-one, a Curcumin Analogue

Abstract

Background: Curcumin is a naturally occurring bis-chalcone derivative in the commonly used Indian spice turmeric and is well-known for its potent chemopreventive, anti-angiogenic, anti-cancer properties. 3,5-bis[(E)-thienylmethylene] piperidin-4-one (BTMP) is the newly synthesised synthetic analogue of curcumin that is tested for its antioxidant and antimicrobial properties in vitro. Objectives: This study was to determine the antioxidant activity and antibacterial potentials of newly synthesised analogues of curcumin viz., 3,5-bis[(E)thienylmethylene] piperidin-4-one (BTMP), was examined in vitro. Materials and Methods: BTMP was evaluated for its antioxidant and antimicrobial using 1,1-diphenyl-2-picryl hydroxyl (DPPH • ) radical scavenging assay, 2,2'-azinobis3-ethyl benzothiazoline-6-sulfonic acid (ABTS •+ ), ferric reducing antioxidant power (FRAP), nitric oxide scavenging assay, superoxide anion radical scavenging assay (O2 •− ), hydrogen peroxide scavenging, reducing ability assay, metal ion chelating and phosphomolybdenum assays. Results: 40µg/ml of BTMP showed higher antioxidant activity than the other three doses due to its highest free radical scavenging ability at this particular dose. All doses of BTMP showed antimicrobial activity against E. coli and S. aureus. 40µg/ml of BTMP showed the highest zone of inhibition against both tested pathogens. Conclusion: The introduction of basic functionality and the presence of exocyclic double bonds of BTMP has significantly contributed to the antioxidant activity and antimicrobial activity against both gram-positive and gram-negative bacteria.

Monoketone Curcuminoids: An Updated Review of Their Synthesis and Biological Activities

“…Various aromatic aldehydes can be used, because they do not undergo enolization and, hence, cannot function as the nucleophilic component of the reaction. CSC can be base-or acid-catalyzed; moreover, in both cases, excess aromatic aldehyde is employed to ensure that MKC is the final product (Scheme 1a) [18]. Alternatively, excess ketone, instead of excess aromatic aldehyde, can be used, so that the ketone condenses with one aldehyde only.…”

Monoketone Curcuminoids: An Updated Review of Their Synthesis and Biological Activities

“…Various aromatic aldehydes can be used because they do not undergo enolization and hence cannot function as the nucleophilic component of the reaction. CSC can be base-or acid-catalyzed; in both cases, excess aromatic aldehyde is employed to ensure that MKC is the final product (Scheme 1a) [16]. Alternatively, excess ketone instead of excess aromatic aldehyde can be used, so that the ketone condenses with one aldehyde only.…”

“…In some methodologies, at the end of the reaction, the reaction mixture is neutralized by adding a hydrochloric acid (HCl) solution to the vessel [21] In most cases, the resulting solid is separated from the reaction mixture by vacuum filtration and washed with ice water, to remove excess base. Finally, the solid product is dried and recrystallized from hexane/ethyl acetate, EtOH, or EtOH/ to obtain pure crystals [16,[21][22][23][24]. Besides NaOH, calcium hydroxide (Ca(OH)2) has been used as a basic catalyst in CSC to obtain MKCs.…”

“…Nivedha and co-workers investigated the antimicrobial activity of compound 188 against Escherichia coli and Staphylococcus aureus was by using the inhibition zone method. The authors reported that 188 at 40 μg/mL displays the largest inhibition zone against both bacteria [16]. More recently, Jonathan and co-workers investigated the antimicrobial activity of compounds 190 and 191 against Bacillus subtilis, S. aureus, E. coli, and Pseudomonas aeruginosa by using the disc diffusion method, to find that both the compounds control the E. coli growth, even at low concentrations.…”

“…Recently, the antioxidant activity of compound 188 has been investigated by using nine different assays (2,2'-azino-bis-3-ethyl benzothiazoline-6-sulfonic acid (ABTS •+ ),1,1-diphenyl-2-picryl hydroxyl (DPPH • ) radical scavenging assay, nitric oxide scavenging assay, ferric reducing antioxidant power (FRAP), hydrogen peroxide scavenging, superoxide anion radical scavenging assay (O2 •− ), reducing ability assay, and phosphomolybdenum assay metal ion chelating assay), to find that compound 188 at 40 μg/mL displays antioxidant activity in all of them [16].…”