## 3 Results and Discussion
### Scanning Electron Microscopy and EDX Analysis  
Synthesized AgNPs from the various extracts exhibited dispersion throughout the samples with some level of agglomeration (Figure 3A,C, Figure 4A,C and Figure 5A,C). [PERSON] et al. [74] have reported that this could be due to a dehydration-induced aggregation of AgNPs. The spherical shape of nano-sized (<100 nm) AgNPs was confirmed by micrographs (Figure 3A,C, Figure 4A,C and Figure 5A,C). Similarly, previous reports on synthesized AgNPs from _B. prionitis_[10] and _B. cristata_[75] have highlighted their predominantly spherical morphology. All prepared samples for SEM analysis displayed considerable NP agglomeration, thus SEM micrographs were not ideal for assessing NP size. [PERSON] et al. [75] have suggested that AgNPs synthesized from the leaf extracts of _B. cristata_ were agglomerated because the biological constituents may have gathered smaller particles, forming larger knobs. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Crude Extract**} & **Leaves** & **Stem** & **Leaves** & **Stem** \\ \cline{2-5}  & \multicolumn{2}{c}{**Dried AgNPs Yield (g)**} & \multicolumn{2}{c}{**Percentage Yield (\%)**} \\ \hline Methanol & 0.032 & 0.030 & 0.32 & 0.30 \\ Fresh & 0.030 & 0.010 & 0.12 & 0.04 \\ Powdered & 0.026 & 0.050 & 0.26 & 0.50 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Percentage yield of the leaf and stem synthesized extracts of _B. albostellata_. Figure 1: Silver nanoparticles synthesized from _B. albostellata_ leaf and stem extracts: (**A**) Leaf and stem methanolic extracts before AgNPsNT synthesis; (**B**) Leaf and stem methanolic extracts after incubation with AgNO3; (**C**) Fresh leaf and stem extracts before AgNPsNT synthesis; (**D**) Fresh leaf and stem extracts after incubation with AgNO3; (**E**) Powdered leaf and stem extracts before AgNPsNT synthesis; (**F**) Powdered leaf and stem extracts after incubation with AgNO3. Figure 3: Micrographs of AgNPs synthesized from the methanol leaf extracts (**A**,**B**) and stem extracts (**C**,**D**) of _B. albostellata_. (**A**,**C**) Aggregated AgNPs; (**B**,**D**) EDX spectroscopy. Circles indicate AgNP agglomeration. Figure 2: UV-visible spectroscopy of AgNPs synthesized from methanol, fresh and powdered leaves, and stem extracts of _B. albostellata_ after 3 h incubation with AgNO\({}_{3}\). ML = Methanol leaf; MS = Methanol stem; FL = Fresh leaf; FS = Fresh stem; PL = Powdered leaf; PS = Powdered stem. EDX confirmed the presence of AgNPs and displayed strong peaks at 3 keV (Figure 3B,D, Figure 4B,D and Figure 5B,D). These peaks confirmed the biosynthesis of AgNPs and the organic compounds which were present on the NPs [76]. AgNPs synthesized from the leaf extracts of _B. prionitis_ also displayed strong peaks at 3 keV [10]. Several studies have confirmed the presence of Ag\({}^{+}\) by observing the energy peak at 3 keV [77, 78]. Overall, AgNPs from the methanolic leaf solution (Figure 3B) displayed the highest percentage of elemental Ag\({}^{+}\) ions (16.87 \(\pm\) 0.89) and the lowest was found in the powdered stems (7.13 \(\pm\) 1.44%) (Table 2). AgNPs from the methanolic stems had the second highest percentage of 14.78 \(\pm\) 3.53. Fresh leaves and stems displayed Ag\({}^{+}\) ions at 9.47 \(\pm\) 1.38% and 8.12 \(\pm\) 0.71%, while the powdered leaf and stem material exhibited percentages at 8.85 \(\pm\) 1.09 and 7.13 \(\pm\) 1.44, respectively (Table 2). [PERSON] et al. [79] have proposed that different plant parts vary in their content of biochemical constituents, thus affecting the synthesis, size, and shape of AgNPs. The higher biosynthesized AgNPs obtained using leaf extracts (relative to the stems) may be due to their high concentration of secondary metabolites, as opposed to the stems, which may promote metal ion reduction [80]. Figure 4: Micrographs of AgNPs synthesized from the fresh leaf extracts (**A**,**B**) and fresh stem extracts (**C**,**D**) of _B. albostellata_. (**A**,**C**) Aggregated AgNPs; (**B**,**D**) EDX spectroscopy.