# Dynamics of Microbial Community Structure and Metabolites during Mulberry Ripening
## 3 Results and Discussion
### Dynamic Changes in Antioxidant Capacity of WHDS during Ripening  
According to the doctrine of oxygen radicals, biological oxidation can be harmful to human health and cause diseases [32], and the antioxidant substances in fruits can scavenge a certain amount of reactive oxygen species (ROS) to keep them in a dynamic equilibrium [33] and protect the body from oxidative damage. The antioxidant capacity of fruits is usually represented by indicators such as ABTS RSA and DPPH RSA [34], with higher scavenging rates corresponding to higher antioxidant capacity. WHDS samples at different maturity levels had some differences in their final antioxidant capacity due to differences in phenolics and flavonoids. As shown in Figure 2a, the ABTS RSA of WHDS was in the range of 0%-94.20 \(\pm\) 2.18%, with the peak occurring at S4. For the same maturity and at different concentrations, the ABTS RSA increased with maturity, with clearance basically stabilising at around 91% at S4. For different maturities and at the same concentration, ABTS RSA did not behave in a regular manner, with low clearance at a sample volume of 0.02 mL and three stages below 50%. As shown in Figure 2b, the trends in DPPH RSA were similar to those in ABTS RSA, which coincided with the trend in grapevine growth [35], with total clearance ranging from 0% to 95.13 \(\pm\) 1.44%, with the peak occurring at S4 and slightly higher than that of ABTS RSA. Clearance was also relatively low at a sample volume of 0.02 mL, with three stages below 50%, until it essentially stabilised at 0.08 mL at approximately 91%. Notably, the antioxidant capacity of WHDS increased with maturity, which is highly similar to the trend in the antioxidant capacity of plums [36], and most of their peaks occurred at S4, suggesting that this may be the optimal consumption stage for the human body to improve antioxidant capacity and scavenge free radicals.  
\begin{table}
\begin{tabular}{c c c c c c} \hline
**Phase** & **S1** & **S2** & **S3** & **S4** & **S5** \\ \hline pH & 3.55 \(\pm\) 0.02c & 3.46 \(\pm\) 0.03d & 3.78 \(\pm\) 0.04a & 3.66 \(\pm\) 0.04b & 3.68 \(\pm\) 0.03b \\ Weight of single fruit (g) & 1.47 \(\pm\) 0.01d & 1.60 \(\pm\) 0.01c & 1.98 \(\pm\) 0.02b & 2.08 \(\pm\) 0.02a & 2.07 \(\pm\) 0.03a \\ Soluble solids (B.rix) & 8.85 \(\pm\) 0.41e & 10.08 \(\pm\) 0.25d & 11.25 \(\pm\) 0.33c & 18.94 \(\pm\) 0.22b & 21.64 \(\pm\) 0.58a \\ Juice yield (\%) & 23.05 \(\pm\) 0.29e & 32.10 \(\pm\) 0.09d & 43.71 \(\pm\) 0.70c & 52.76 \(\pm\) 0.38a & 51.67 \(\pm\) 0.36b \\ Total acid (g/L) & 5.39 \(\pm\) 0.02a & 3.75 \(\pm\) 0.03b & 2.64 \(\pm\) 0.02c & 1.55 \(\pm\) 0.03d & 0.39 \(\pm\) 0.03e \\ Total sugar (g/L) & 0.22 \(\pm\) 0.02e & 0.31 \(\pm\) 0.06d & 0.58 \(\pm\) 0.04c & 0.71 \(\pm\) 0.14b & 0.92 \(\pm\) 0.66a \\ Total phenolics (g/L) & 7.13 \(\pm\) 0.03e & 10.06 \(\pm\) 0.20d & 11.47 \(\pm\) 0.11c & 26.15 \(\pm\) 0.43a & 17.35 \(\pm\) 0.18b \\ Total flavonoids (g/L) & 0.89 \(\pm\) 0.01c & 1.65 \(\pm\) 0.02b & 1.38 \(\pm\) 0.01b & 2.46 \(\pm\) 0.03a & 1.78 \(\pm\) 0.04b \\ Total & 74.73 \(\pm\) 0.62e & 110.74 \(\pm\) 1.54d & 185.97 \(\pm\) 2.72c & 587.60 \(\pm\) 7.38a & 341.09 \(\pm\) 4.81b \\ anthocyanins (mg/L) & & & & & \\ \hline \end{tabular} Note: Different lowercase letters represent significant differences in factors at \(p<0.05\).  
\end{table}
Table 1: Dynamic changes in basic physiological indicators of WHDS during ripening.