## 3 Results and Discussion
### Evaluation of Antiviral Activity of C. myrrha (T.Nees) Engl. Resin Extracts
According to the results of HPLC and GC-MS analysis, polyphenols (i.e., tannic acid, rutin, quercetin, ferulic acid, caffeic acid, naringenin, and ellagic acid) and terpenoids (i.e., furanoeudesma-1,3-diene, curzerene, lindestrene, gazaniolide, -elemene, and -elemene) were detected in the _C. myrrha_ (T.Nees) Engl. resin extracts in this study (Figure 1, Figure 4 and Figure S3). As shown in Figure 1, tannic acid, rutin, and quercetin were the major polyphenols (above 20 g/mL) in the _C. myrrha_ (T.Nees) Engl. resin extracts. As mentioned, the three major polyphenols (tannic acid, rutin, and quercetin) had significant antibacterial effects. In particular, tannic acid may lead to improved antibacterial activity by disturbing the uptake of sugars and amino acids, restricting bacterial growth. According to [PERSON] et al., tannic acid inhibits the growth of _Clostridioides difficile_ strains at concentrations above 16 g/mL [61]. [PERSON] et al., and [PERSON] et al., reported that rutin and quercetin possess antimicrobial efficacy [62; 63]. Polyphenols have been proposed as roles in the disruption of bacterial cell wall homeostasis, nucleic acid synthesis, and energy metabolism. As shown in Figure S3, various terpenoids such as furanoeudesma-1,3-diene, curzerene, lindestrene, gazaniolide, \(\beta\)-elemene, \(\gamma\)-elemene, etc., were observed. Based on the results from previous literature regarding _C. myrrha_ (T.Nees) Engl. resin extracts, furanoeudesma-1,3-diene and curzerene were measured as major compounds [16; 64]. According to the \begin{table}
\begin{tabular}{l c c} \hline \hline
**Sample** & **Ct Value** & **Remaining Amount of Virus (\%)** \\ \hline Water (without virus) & 0 & - \\ Virus (Initial) & 24.809 & 100.00 \\ WD-BC (Final) & 25.121 & 96.69 \\ Extract-coated WD-BC (Final) & 27.105 & 75.66 \\ RH-BC (Final) & 25.137 & 96.52 \\ Extract-coated RH-BC (Final) & 26.941 & 77.40 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The remaining amount of virus in water (without virus), initial (virus in water), RH-BC and WD-BC without _C. myrrha_ (T.Nees) Engl. resin extracts (final after reaction), and _C. myrrha_ (T.Nees) Engl. resin extract-coated RH-BC and WD-BC (final after reaction) after the reaction. Conditions: H1N1 influenza virus (0.1 of MOI) in 3 mL of aqueous solution with 5 mg of _C. myrrha_ (T.Nees) Engl. resin extract-coated biochar; shaken at 120 rpm and stored at 25 \({}^{\circ}\)C for 48 h.  
antiviral activity test, the viral RNA inhibition effects (81.2%) of _C. myrrha_ (T.Nees) Engl. resin extracted using methanol were revealed (Figure 3). In contrast, there was negligible effect on virus RNA inhibition (2.8%) using methanol. The quantities of fumoeudesma-1,3-diene and curzerene in the terpenoids used in the antiviral activity experiment were 74.5 ug/mL and 12.4 ug/mL. Consequently, this finding may originate from terpenoids (i.e., furanoeudesma-1,3-diene and curzerene as the major compounds). The mechanisms of these terpenoids for antiviral activity were deduced to involve the interference of factors on the plasma membrane, viral attachment, antioxidant activity, and cell penetration [16]. Additionally, fumoeudesma-1,3-diene (1118.42 ug/mL) and curzerene (185.34 ug/mL) were found in _C. myrrha_ (T.Nees) Engl. resin extracted using methanol (Figure 4). After the precipitation of RH-BC in _C. myrrha_ (T.Nees) Engl. resin extracts, the concentration of these terpenoids (e.g., furanoeudesma-1,3-diene and curzerene) decreased by about 49% (553.36 ug/mL) and 36% (66.89 ug/mL), respectively (Figure 4). These results suggest that these terpenoids were bound to the surface of RH-BC. The remaining H1N1 influenza virus decreased by approximately 22.6% in aqueous solution with the _C. myrrha_ (T.Nees) Engl. resin extracts coated with RH-BC (Table 4). Possibly, this is due to the coated quantity of terpenoids (i.e., furanoeudesma-1,3-diene (18.4 ug/mL) and curzerene (2.2 ug/mL) onto RH-BC).