Abstract:
avetta crassipes and P. schumanniana are some of the neglected and underutilised, yet useful
medicinal plants in Malawi. In regions where P. crassipes and P. schumanniana leaves are
traditionally used for medicinal purposes, there is lack of scientific understanding regarding their
therapeutic efficacy, chemical composition, and antimicrobial properties. The objective of the
study was to compare ethno medicinal use, phytochemical composition and antimicrobial activity
of P. crassipes and P. schumanniana plant leaves. The study was conducted in March, 2022. This
study used both qualitative and quantitative methods. In ethno medicinal survey, simple random
and snowball sampling procedures were used to select sites and respondents respectively. Data
were analysed using SPSS version 20 and STATA version 16. Chi-square test was used to
determine significant differences or associations in parameters of interest between the two plant
species. For phytochemical analyses, qualitative chemical methods of analysis were used to study
phytochemical compounds. For microbial effects, the diffusion disc method was used to assess
antimicrobial activity of the leaf extracts against E coli and S. aureus. The zone of inhibition of
P. crassipes and P. schumanniana aqueous leaf extract in mm were entered into STATA version
16, and thereafter were subjected to One Way Analysis of Variance (ANOVA). Some diseases
that were reported to be managed by P. schumanniana and were common whilst others were
specific to one plant species. P. schumanniana was commonly used to manage cough while P.
crassipes was commonly used as libido enhancer. Phytochemical analysis revealed the presence
of bioactive compounds in P. crassipes leaves which were steroids, tannins, anthocyanin and
anthraquinones, while P. schumanniana leaves contained saponins, terpenoids/steroids, tannins
and anthocyanins. Alkaloids and flavonoids were not detected in both plant species. The data
showed a concentration dependent efficacy on E. coli while S. aureus was resistant to both
species. The most effective concentration (100 µg/mL) of P. crassipes and P. schumanniana
aqueous leaf extract recorded highest mean zone of inhibition of 8.10±0.89 mm (p = 0.915) and
7.73±0.67 mm (p = 0.999) for P. crassipes and P. schumanniana, respectively. This study
validates the traditional uses of Pavetta schumanniana and Pavetta crassipes, highlights their
potential as sources of antimicrobial agents, and provides a foundation for further research into
their bioactive compounds.
