In vitro antibacterial activity of Loxostylis alata extracts and isolated compounds against Salmonella species

BMC Complementary Medicine and Therapies

Marthie M. Ehlers¹  Balungile Madikizela²  Sanah M. Nkadimeng²  Aroke S. Ahmed²  Lyndy J. McGaw²  Muna Ali Abdalla³  Dorcas A. Gado⁴ 

[1] Department of Medical Microbiology, Faculty of Health Sciences, University of Pretoria, PO Box X323, Arcadia 0007, Pretoria, South Africa;National Health Laboratory Service, Tshwane Academic Division, Pretoria, South Africa;Phytomedicine Programme, Department of Paraclinical Sciences, University of Pretoria, Private Bag X04, Onderstepoort 0110, Pretoria, South Africa;Phytomedicine Programme, Department of Paraclinical Sciences, University of Pretoria, Private Bag X04, Onderstepoort 0110, Pretoria, South Africa;Department of Food Science and Technology, Faculty of Agriculture, University of Khartoum, 13314, Khartoum North, Sudan;Phytomedicine Programme, Department of Paraclinical Sciences, University of Pretoria, Private Bag X04, Onderstepoort 0110, Pretoria, South Africa;Regional Laboratory for Animal Influenzas and other Transboundary Animal Diseases, National Veterinary Research Institute, PMB 01, Vom, Plateau State, Nigeria;

关键词: Antimicrobial;    Salmonella;    Cytotoxicity;    Loxostylis alata;    Biflavonoid;   

DOI  :  10.1186/s12906-021-03292-4

来源: Springer

【 摘 要 】

BackgroundOwing to antibiotic resistance, alternative antimicrobials from medicinal plants are receiving attention as leads for anti-infective agents. This study aimed to investigate selected tree species and their constituents for activity against bacterial foodborne pathogens, particularly Salmonella serovars.MethodsAntibacterial activity of ten plant species was determined by serial microdilution against bacteria implicated in causing gastrointestinal ailments. Active compounds were isolated from Loxostylis alata using bioassay-guided fractionation. Antioxidant activity was determined using free-radical scavenging assays. Cytotoxicity and genotoxicity of the extracts was ascertained on Vero cells, and using the Ames assay respectively.ResultsExtracts had low to moderate MIC values from 0.04 to 2.5 mg/mL. Protorhus longifolia and Loxostylis alata were most active and L. alata had the highest selectivity index value (2.51) against Salmonella Typhimurium, as well as high antioxidant activity. Cytotoxicity values ranged from 0.02 to 0.47 mg/mL, while tested extracts were not genotoxic. Bioactive compounds isolated from L. alata included delicaflavone and a polymethoxyflavone.ConclusionsThe Loxostylis alata leaf extract had strong activity against Salmonella serovars but isolated compounds were less active, indicating likely synergistic effects. Extracts of L. alata are promising candidates for development of antimicrobial preparations or food additives against microbial contamination.

【 授权许可】

CC BY