Green Synthesis of Na abietate Obtained from the Salification of Pinus elliottii Resin with Promising Antimicrobial Action

Abstract

The growing concern about the emergence of increasingly antibiotic-r4esistant bacteria imposes the need to search and develop drugs to combat these microorganisms. This, combined with the search for low-cost synthesis methods, was the motivation for the elaboration of this work. Abietic acid present in the resin of Pinus elliotti var. elliotti was used to generate a sodium salt by salification. The synthesis route was low-cost, consisting of only two reaction steps at mild temperatures without toxic organic solvents, and eco-friendly and easy to conduct on an industrial scale. Sodium abietate (Na-C20H29O2) was characterized by mass spectrometry, infrared spectroscopy, elemental analysis, X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. To perform the antimicrobial tests, the determination of minimum inhibitory concentration and the disk diffusion assay was performed. The results obtained showed that the salt Na abietate performed an antimicrobial action against the bacterial strains S. aureus, E. coli, L.monocytogenes, and S. enterica Typhimurium and the yeast C. albicans. The disk diffusion test showed a high inhibition potential against S. enterica compared to the standard antimicrobial tetracycline, as an inhibition index of 1.17 was found. For the other bacterial strains, the inhibition values were above 40%. The MIC test showed promising results in the inhibition of E. coli, L. monocytogenes, and C. albicans, indicating bacteriostatic activity against the first microorganism and bactericidal and fungicidal activities against the others. Therefore, the results showed the action of Na abietate as a possible effective antimicrobial drug, highlighting its sustainability within a circular economy.

Bimetallic bis-Aroyldihydrazone-Isatin Complexes of High O=V(IV) and Low Cu(II) Valent Ions as Effective Biological Reagents for Antimicrobial and Anticancer Assays

“…The biomolecular interactions of a metallo-drug depend on its stability in the studied reaction media, i.e., DMSO [ 7 , 8 ]. The concentration of the ligand and the two complexes was established by dissolving them in DMSO (1.0 × 10 −4 mol dm −3 ).…”

“…H 2 Lph, VOLph, and CuLph demonstrated less effectiveness compared to these antibiotic drugs (fluconazole and ciprofloxacin), as listed in Table 2 . Furthermore, DMSO was used in the same study as a reference control solvent, and did not exhibit any considerable inhibiting action against the titled microorganisms’ growth [ 8 ].…”

“…The modified lipophilic feature could improve the antiproliferative potential of VOLph and CuLph chelates compared to H 2 Lph (i.e., free ligand), referring to the role of the chelation effect, i.e., Tweedy’s theory of chelation, as represented for the bacterial and fungal studies [ 29 , 51 , 52 ]. The higher activity of VOLph than CuLph was interpreted as being due to the more highly lipophilic character of VOLph, referring to the more positively charged O=V 4+ ion with high electrophilicity compared to that of CuLph with a less positively charged Cu 2+ ion with lower electrophilicity, as demonstrated by the IC 50 values (neutralization effect) [ 8 , 46 , 47 ]. However, H 2 Lph, VOLph, and CuLph have less antiproliferative action compared to the anticancer drug vinblastine.…”

“…Therefore, many large metal–organic framework complexes consisting of positively charged M n+ ions have been constructed, providing enhanced medicinal applicability and fewer biological side effects [ 7 ]. In addition, derivatives of chelating metal–organic hydrazone complexes were designed for their effectiveness as anticancer candidates and antimicrobial reagents, considering the theory of Tweedy’s chelating effect [ 8 ] to distinguish their improved Lewis acidic characters and lipophilicity compared to their free aryl/arylhydrazone-based ligands. These features could be the reason for their penetration into the microbial and cancer cell walls and their interacting or distorting effect on cell DNA [ 9 ].…”

Eucalyptus globulus Mediated Green Synthesis of Environmentally Benign Metal Based Nanostructures: A Review

“…Plants that are not limited to a specific area and season should be explored in the future for the synthesis of NPs. For example, plants belonging to the Pine family have been explored for the synthesis of NPs [ 77 , 156 , 157 ]. These readily available evergreen plants could avoid the limitation of seasonal availability and can be employed as an alternative to seasonal plants.…”