Synergistic interactions of phytochemicals with antimicrobial agents: Potential strategy to counteract drug resistance

New Tricks for Old Guys: Recent Developments in the Chemistry, Biochemistry, Applications and Exploitation of Selected Species from the Lamiaceae Family

“…Carnosic acid, together with carnosol (43) and rosmanol (44), are diterpenoids belonging to the metabolic pool of rosemary, responsible for most of its biological activities. In a recent survey of Sicilian R. officinalis, the ethyl acetate and ethanol extracts showed the presence of several polyphenols subdivided in organic (14), genkwanin (25), salvigenin (33), and diterpenes: carnosol (43), carnosic acid (49) and methyl carnosoate (50). Rosmarinic and carnosic acids were largely the main components contributing to the antioxidant properties of the extracts.…”

“…[423] An exhaustive study of the chemical composition of a large sampling of Sicilian O. vulgare ssp. hirtum carried out some years ago allowed to establish the chemical composition of ethyl acetate and ethanol extracts: four flavanones (eriodictyol 7-O-rutinoside (6), aromadendrin (7), eriodictyol (8) and naringenin (9)), seven flavones (luteolin (5), sorbifolin (10), cirsiliol (11), apigenin (12), cirsilineol (13), cirsimaritin (14) and xanthomicol (15)), and two organic acids ((caffeic (1) and rosmarinic (4)) have been detected and quantified. The antioxidant effectiveness of the extracts, obtained with different methods (ABTS, DPPH, FRAP, ORAC, βcarotene bleaching test to quote the most applied), was quite significant and of course associate with the polyphenols content previously described.…”

“…[56] O. vulgare is one of the main species of this genus and then the most studied, however, other minor species show interesting chemical composition associated with biological activities, for example a study of the chemical characterization and the evaluation of antimicrobial, enzyme inhibitory, and antioxidant activities of methanol and water extracts of Turkish O. onites has been recently reported. [424] In total 28 components belonging to polyphenols, flavonoids, terpenoids, organic acids and esters have been identified: 3-O-(4-coumaroyl)quinic acid (16), acacetin (17), cirsimaritin (14), naringenin (9), tuberonic acid glucoside (18), ferulic acid (3), apigenin-7,4'-dimethyl ether (19), azelaic acid (20), baicalin (21), casticin (22), cirsiliol (11), dihydrorobinetin (23), gardenin B (24), genkwanin (25), isoferulic acid (26), kaempferol (27), nevadensin (28), oroxylin A 7-O-glucuronide (29), quercetin (30), rosmarinic acid methyl ester (31), sakuranetin (32) and salvigenin (33).…”

“…This problem is particularly acute in the hospitals and for some particular and very dangerous bacterial strains as Mycobacterium tuberculosis , the etiological agent of tuberculosis (TB), which in these last years, showed a broad recrudescence becoming one of the main causes of death . New strategies such as the use of a multi‐components therapy in the hope to exploit synergic and/or additive effects, or the analyses of new and little explored new sources has been taken in consideration . Very recently some cyclic heptapseudopeptides have been synthetized taking paradoxically inspiration from a Staphylococcus aureus toxin, showing interesting activities against antibiotic‐resistant Gram ‐positive and ‐negative pathogens …”

“…[13] New strategies such as the use of a multi-components therapy in the hope to exploit synergic and/or additive effects, or the analyses of new and little explored new sources has been taken in consideration. [14][15][16] Very recently some cyclic heptapseudopeptides have been synthetized taking paradoxically inspiration from a Staphylococcus aureus toxin, showing interesting activities against antibioticresistant Gram-positive and -negative pathogens. [17] A further and promising tool for the development of the natural products and herbal extracts is the so called 'drug repurposing', which has been defined as the 'Studying the drugs that are already approved to treat one disease or condition to see if they are safe and effective for treating other diseases' as elaborated by the National Centre for Advancing Translational Sciences (NCATS, Bethesda, Maryland, USA) of the National Institute of Health (NIH, Bethesda, Maryland, USA).…”