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.
ABSTRACT
Objective: To evaluate the anti-infectious and antioxidant activities of hydroethanolic extract of Canarium schweinfurthii on broiler chickens infected by Salmonella enterica serovar Typhimurium, known to be threatening public health. Methods: Animals were divided into six groups of eight animals per group: the normal control group, negative control group, positive control group and three test groups receiving the plant extract at 5, 19 and 75 mg/kg bw, respecively. The evolution of the disease as well as the effectiveness of the treatment were monitored by stool culture from the second day post infection until the end of the treatment. In addition, the effects of treatment on growth performances and feed conversion efficiency of broilers were evaluated. For the assessment of antioxidant status, enzymatic and non-enzymatic biomarkers such as catalase, glutathione peroxidase, malondialdehyde and nitric oxide were evaluated in the serum and tissues of animals. Results: The infected chickens treated with oxytetracycline recovered on day 7 after treatment, while animals treated with 19 and 75 mg/kg of Canarium schweinfurthii extract recovered on day 9 and those with 5 mg/kg of the extract on day 10. Salmonella infection caused a decrease on catalase and glutathione peroxidase activities; the administration of various doses of Canarium schweinfurthii extract increased these enzymatic activities. Animals receiving the extract at 5 mg/kg showed a significant increase in catalase activity in serum, heart and lungs while all concentrations of the extract significantly increased glutathione peroxidase activity in the serum, liver and spleen. Concerning non-enzymatic biomarkers, Salmonella infection caused a significant increase of nitric oxide and malondialdehyde concentration in the liver and lungs. Treatment with 75 mg/kg of the extract significantly reduced nitric oxide concentration in the heart and lungs while each dose of the extract reduced and normalized the malondialdehyde level in the serum. Additionally, malondialdehyde production was significantly decreased in the liver, heart and lungs after administration of Canarium schweinfurthii extract at all doses. Conclusions: The hydroethanolic extract of Canarium schweinfurthii attenuates oxidative stress, and is effective in the treatment of avian salmonellosis.
ABSTRACT
Objective:To determine inhibitory activity of methanolic leaf extract of Piper umbellatum and Persea americana (P.americana) (traditionally used in Cameroon against diabetes) on α-glucosidase,β-glucosidase,maltase-gluconmylase,aldose reductase and aldehyde reductase activities,enzymes involved in starch digestion or diabetic complications.Methods:The methanol extracts from Piper umbellatum and P.americana were prepared by maceration.To assess relative efficacy of these extracts,the determination of concentrations that were needed to inhibit 50％ of enzyme activity was done,whereas,gas chromatography-mass spectrum was used to identify components from extracts that may be responsible for the activities.Resullts The tested extracts strongly inhibited α-glucosidase,maltase-glucoamylase,aldose reductase and aldehyde reductase activities with IC50 ranging from (1.07 ± 0.03) to 01.77 + 1.17) μg/mL.Among the tested extracts,P.americana was the most active against sensitive enzymes (IC50 of 1.07 ± 0.03 to 15.63 ± 1.23).But,none of the extracts showed interesting inhibitory effect against β-glucosidase as their percentage inhibitions were less than 16％.From gas chromatographymass spectrum analysis,10 and 8 compounds were identified in Piper umbellatum and P.americana extracts respectively,using NIST library 2014.Conclusions:Results of this study provide the scientific credential for a prospective usage of these plants to treat diabetes.