In vitro Antisalmonellal and Antioxidant Activities of Leaves Extracts of Tectona grandis L. F. (Verbenaceae)

Abstract

Aim: Study aimed to evaluate the in vitro antisalmonellal and antioxidant properties of Tectona grandis, a medicinal plant commonly used in traditional Cameroonian medicine for the treatment of typhoid fever.
 Study Design: In vitro Antimicrobial and antioxidant analyses of plant extract using established protocols.
 Place and Duration of Study: Plant materiel collection at Loum (Moungo Division, Littoral region of Cameroon), identification at the National Herbarium of Cameroon, extraction of plant and all analyses at the Research Unit of Microbiology and Antimicrobial Substances, Department of Biochemistry, University of Dschang-Cameroon, between August 2018 and April 2019.
 Methodology: In vitro antisalmonellal activity of Tectona grandis extracts was evaluated by the liquid microdilution method as well as their antioxidant activity using by standard methods of H2O2 trapping, FRAP, DPPH radical trapping and OH radical trapping. Quantification test of total phenols and flavonoids and phytochemical screening of extract were also done.
 Results: The results showed that most of the Tectona grandis extracts had minimal inhibitory concentrations (MICs) ranging from 64 to 1024 μg/mL. Ethanolic extract, 70% ethanol extract and aqueous decoction are the most effective compared to aqueous extracts with activities between 64 and 128 μg/mL on the bacteria tested. Antioxidant tests showed that all extracts except macerated and aqueous infused extracts exhibited high DPPH trapping activities. The antioxidant activities of the extracts are proportionally linked in most cases to their flavonoid and total phenol contents at a concentration of 200 µg/mL. Aqueous decoction showed better H2O2 trapping activity at concentrations less than or equal to 25 µg/mL.
 Conclusion: These results show that the ethanolic extract and decocted aqueous of Tectona grandis leaves can be used as an alternative to treat salmonellosis.

Toxicological Profile of the Aqueous Extract of Tectona grandis L.F. (Verbenaceae) Leaves: A Medicinal Plant Used in the Treatment of Typhoid Fever in Traditional Cameroonian Medicine

“…This extract does not cause anorexia in animals. Indeed, the absence of tannins in this extract [ 13 ], known for their anorexic and antinutritional properties, can confirm these results.…”

“…Tectona grandis is a plant belonging to the Verbenaceae family, which is commonly found in India and tropical countries, and well known as “Teak.” The different parts (leaves, bark, and root [ 8 , 9 ]; heartwood [ 10 ]; root heartwood [ 11 ]) of this plant contain many secondary metabolites which justify its traditional use as an anti-inflammatory, laxative, astringent, and analgesic plant [ 12 ]. In Cameroon, it is traditionally used in the Moungo Department (Loum) to treat diabetes and typhoid fever, and its in vitro and in vivo antityphoid activity has recently been proved [ 13 ]. Compounds isolated from Tectona grandis leaves have many biological activities: naphthotectone, anthratectone, and tectoionol A have allelopathic activity [ 14 ], while tectograndone, grandiquinone A, and hydroxysesamone have antibacterial and antimalarial activities [ 15 ].…”

In vitro and in vivo Antioxidant potential of aqueous and hydroethanolic extracts leaves ofDracaena deistelianaEng. (Dracacenaceae)

“…The test was completed when no more than two colonies of salmonella were found in the animals' blood after the blood culture. Food consumption as well as body weight of animals were recorded daily as described by [12].…”

“…It is made available under a preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in The copyright holder for this this version posted January 25, 2023. ; https://doi.org/10.1101/2023.01. 24.525426 doi: bioRxiv preprint Thus, treatment sources to combat both Salmonella infection and oxidative stress would improve the management of patients suffering from these infections [11,12,13,14,15]. Since ancient times, medicinal plants have always been part of the basic knowledge of all human societies [16].…”

“…Thus, treatment sources to combat both Salmonella infection and oxidative stress would improve the management of patients suffering from these infections [11,12,13,14,15]. Since ancient times, medicinal plants have always been part of the basic knowledge of all human societies [16].…”