## 4 Discussion  
In the present study, 16 endophytic fungi assigned to 7 fungal genera were successfully isolated from _A. yunmanensis_, among which 43.75% of the fungal endophytes originated from roots, 37.50% from stems, and 18.75% from leaves. In contrast, the distribution of fungi was found to be highest in leaves of _Paeonia lactiflora_ Pallas and _Epheda pachyclada_ Boiss [29]. Among seven fungal genera identified, _Fusarium_, _Penicillium_, _Aseggillus_, and _Neopsestalotiopsis_ were the most commonly isolated genera colonizing into medicinal plants [1,8,30], while \begin{table}
\begin{tabular}{l c c} \hline \hline  & \multicolumn{2}{c}{**The Free-Radical Scavenging**} \\ \multicolumn{1}{c}{**Compounds**} & \multicolumn{2}{c}{**Activity IC\({}_{50}\) (mM)**} \\ \cline{2-3}  & **DPPH** & **Hydroxyl** \\ \hline \(p\)-hydroxybenzeneacetic acid (**4**) & nd & nd \\
2-(4-hydroxyphenyl)ethanol (**5**) & 5.33 \({}^{\circ}\) \(\pm\) 0.06 & 3.97 \({}^{\text{d}}\) \(\pm\) 0.11 \\ Salicylic acid (**6**) & 0.95 \(\pm\) 0.08 \({}^{\text{b}}\) & 1.92 \(\pm\) 0.61 \({}^{\text{c}}\) \\
2-hydroxybenzeneacetic acid (**7**) & nd & nd \\ Indole-3-acetic acid (**8**) & nd & nd \\
6,8-dihydroxy-3-methylisocoumarin (**9**) & nd & nd \\
2-acetyl-1,4,5,7-tetrahydro-hydroxy-9,10-anthraquinone (**10**) & nd & nd \\ Daidzein (**11**) & nd & nd \\ Isoformonentin (**12**) & 1.02 \(\pm\) 0.09 \({}^{\text{c}}\) & 1.14 \(\pm\) 0.25 \({}^{\text{b}}\) \\
8-adecinone (**13**) & nd & nd \\
8-2\({}^{\text{f}}\)-deoxyadenosine (**14**) & nd & nd \\ Cyclo-Pro-Val (**15**) & nd & nd \\ Ascorbic acid & 0.42 \(\pm\) 0.18 \({}^{\text{a}}\) & 0.82 \(\pm\) 0.17 \({}^{\text{a,b}}\) \\ \hline \hline \end{tabular} Note: (nd). not determined. Values with different letters are significantly different according to the LSD test (\(p<\) 0.05).  
\end{table} 
Table 2: _Cont._  
Figure 3: Oxidative stress–alleviating potential of FUS. (**A**) Effect of FUS on the survival of _S. cerevisiae_ BY4741. (**B**) Survival of _S. cerevisiae_ pretreated with 2 mM and 4 mM FUS under H\({}_{2}\)O\({}_{2}\) stress. Ascorbic acid (AA) was used for comparison. _Purpurecillium_ and _Simplicillium_ served as a potent biocontrol agent against plant diseases on crops [31; 32]. This result supported an assumption that distribution and the culturable fungi community are greatly affected by isolation methods and the environmental and host-mediated factors in play. To the best of our knowledge, this is the first study on the isolation and identification of endophytic fungi from _A. yunnanensis_. Using chemical analysis, _F. foetens_ AQF6 isolated from roots was found to be a prolific source of plant-derived compounds. _F. foetens_ is a phytopathogenic fungus that causes damping-off of rooibos and the destructive vascular wilt disease in _Begonia_ plants [33]. In addition, _F. foetens_ associated with maize produced mycotoxins including beauvericin and four fusaric acid analogs [34]. In our study, the crude extract of _F. foetens_ AQF6 was rich in phytochemical compounds including polyphenols and flavonoids whose antioxidant potential was about 2-fold higher than _Colletotrichum gloeosporoides_ OI-L6 from _Oroxylum indicum_ (L.[PERSON] [PERSON] [7]. Chemical investigation of the AQF6 extract revealed the presence of 15 plant-derived compounds divided into five groups: sesquiterpenenoid (FUS), alkaloids (indole-3-acetic acid, \(\beta\)-2-deoxyadenosine, \(\beta\)-adenosine, and cyclo-Pro-Val), simple phenolics (2-hydroxybenzeneacetic acid, \(p\)-hydroxybenzaldehyde), 2-(4-hydroxyphenyl)ethanol, \(p\)-hydroxybenzeneacetic acid, phenylacetic acid, salicylic acid), flavonoids (6,8-dihydroxy-3-methylisocoumarin, isoformontein, daidzein), and anthraquinone (2-acetyl-1,4,5,7-tetrahydroxy-9,10-anthraquinone). Of note, the chemical profile of AQF6 was completely different from previously published _F. foetens_ strains.