## 3 Results and Discussion
### Comparison with Spectrophotometry
#### 3.4.2 Comparison Results for Fruit and Tablet Samples  
Three tomatoes and three nectarines selected from the market and a bottle of VC tablets, which can be purchased as an over-the-counter (OTC) drug (100 mg VC per tablet, made from Northeast Pharmaceutical Group Co., Ltd.), were used as test samples and treated to obtain the actual samples. The proposed methods and spectrophotometry were use to measure the samples and compare the VC concentrations measured by spectrophotometry with those of the proposed methods. The results are shown in Table 4. The VC concentrations in the VC tablets were measured as 90.325, 86.275, 85.850, and 85.108 mg per tablet (calculated from the concentrations of the sample solution in Table 4) by L, grayscale, log-grayscale, and spectrophotometry, respectively. These results can be regarded as normal for over-the-counter (OTC) drugs.  
\begin{table}
\begin{tabular}{l l l l l l l l l l} \hline \hline \multirow{2}{*}{**Measuring**} & \multicolumn{2}{c}{**L (\(\upmu\)g/mL)**} & \multicolumn{2}{c}{**Grayscale (\(\upmu\)g/mL)**} & \multicolumn{2}{c}{**log-Grayscale**} & \multicolumn{2}{c}{**Spectropho-**} \\  & & & & & (\(\upmu\)g/mL) & & **Tometry(\(\upmu\)g/mL)** & **P** \\ \cline{2-10}  & **Mean** & **SD** & **Mean** & **SD** & **Mean** & **SD** & **Mean** & **SD** & \\ \hline Nectarine1 & 1.43 & 0.04 & 1.43 & 0.15 & 1.44 & 0.15 & 1.44 & 0.59 & 0.998 \\ Nectarine2 & 1.74 & 0.09 & 1.77 & 0.17 & 1.78 & 0.16 & 2.07 & 0.59 & 0.580 \\ Nectarine3 & 1.47 & 0.06 & 1.49 & 0.22 & 1.51 & 0.22 & 1.70 & 0.32 & 0.598 \\ Tomato1 & 3.11 & 0.14 & 3.20 & 0.04 & 3.20 & 0.04 & 3.33 & 0.56 & 0.838 \\ Tomato2 & 3.50 & 0.12 & 3.56 & 0.03 & 3.56 & 0.03 & 3.75 & 0.14 & 0.056 \\ Tomato3 & 4.57 & 0.01 & 4.49 & 0.04 & 4.48 & 0.04 & 4.49 & 0.60 & 0.982 \\ Tablet & 3.61 & 0.14 & 3.45 & 0.10 & 3.4 & 0.09 & 3.40 & 0.11 & 0.167 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Measurement of VC in fruits and tablets by the proposed methods and spectrophotometry (\(\upmu\)g/mL) and contrast results of L, grayscale, and log-grayscale, and spectrophotometry by one-way analysis of variance (ANOVA).  
\begin{table}
\begin{tabular}{l l l l l l l l l l} \hline \hline
**Measuring Method** & \multicolumn{4}{c}{**Measured Concentrations (\(\upmu\)g/mL)**} & \multicolumn{1}{c}{**P**} & \multicolumn{1}{c}{**SD**} \\ \hline L & 1.02 & 1.25 & 1.92 & 2.24 & 2.88 & 3.47 & 4.01 & 0.062 & 0.15 \\ grayscale & 0.90 & 1.14 & 1.77 & 2.33 & 2.99 & 3.54 & 4.01 & 0.080 & 0.18 \\ log-grayscale & 0.90 & 1.14 & 1.76 & 2.34 & 2.99 & 3.54 & 4.01 & 0.079 & 0.18 \\ spectrophotometry & 1.04 & 1.43 & 2.07 & 2.53 & 2.92 & 3.70 & 4.34 & 0.224 & 0.16 \\ \hline \hline \end{tabular}
\end{table}
Table 3: The measured concentration values of L, grayscale, log-grayscale, and spectrophotometry on the standard solutions (n = 3), and the results of the independent-sample T-test and the standard deviation (SD) of L, gray, log-grayscale, and spectrophotometry.  
One-way ANOVA was used to respectively analyze the seven sets of data measured based on L, grayscale, and log-grayscale with the data of spectrophotometry. The probability P was also obtained. The P-value of one-way ANOVA for the seven sets of data is shown in Table 4, and all P-values were greater than 0.05, so there was no significant difference between L, grayscale, and log-grayscale and spectrophotometry, which verified the feasibility of the proposed method. In addition, recovery tests were performed with the standard addition method, the results of which are listed in Table 5.