# Development and Effect Analysis of UVB-LED General Lighting to Support Vitamin D Synthesis
## 4 Results and Analysis  
Blood samples from the caudal vein were obtained to analyze the vitamin D levels in the test animals. The first blood sample measured 0.5 mL and was injected into a vacutainer tube with a clot activator. It was stored at room temperature for 15-20 min for coagulation before it was centrifuged at 3000 rpm for 10 min for separation. The separated blood was kept at a consistent \(-\)70 \({}^{\circ}\)C freezer before analysis. The amount of 25-hydroxyvitamin D [25(OH)D] in this serum was determined using a vitamin D assay kit (Cayman, 501050) through an enzyme-linked immunosorbent assay (ELISA). In addition, all samples were analyzed by applying the same method, according to the manual of the kit provided. The stored serum was diluted as per the analysis kit manufacturer's instructions and then transferred to a microplate. A standard reagent curve was calculated to quantify the amount of 25(OH)D present in the serum. The results of this experiment were analyzed using parametric multiple comparison procedures and non-parametric multiple comparison procedures under the assumption of normality. If the  
Figure 5: Animal experiment schedule. one-way analysis of variance (ANOVA) results were significant, [PERSON]'s multiple comparison test was used to compare the before and after values. If the [PERSON] H-test analysis results were significant, [PERSON]'s multiple comparison test was used. Prism 5.03 (GraphPad Software Inc., San Diego, CA, USA) was used for statistical analysis. A p-value less than 0.05 was determined to be statistically significant. Tables 3-5 each show the rat serum 25(OH)D analysis at D0 (start date), D7 (7 th day), and D14 (14 th day). The pre-experiment (D0) 25(OH)D level analysis as shown in Table 3 showed that G1 (test group) and G2 (control group) had 12.17 ng/mL and 11.85 ng/mL, respectively. The 25(OH)D level was higher in the G1 group despite being in an identical lighting environment for the acclimatization period (one week). However, the difference was insignificant at 0.32 ng/mL. In Table 4, the analysis from the seventh day showed that G1 (test) group had a 25(OH)D level of 15.10 ng/mL and G2 (control) group had a level of 14.13 ng/mL with an increase of 6.8% (0.97 ng/mL) in the rats exposed to the test lighting. Additionally, the fourteenth day analysis results in Table 5 showed that the G1 group had 13.22 ng/mL and the G2 group had 12.32 ng/mL, with the G1 group showing 7.3% (0.9 ng/mL) higher vitamin D levels. In addition, the results showing the change in the 25(OH)D content of each animal at the time of blood collection are shown in Table 6 and visualized as shown in Figure 6.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**D7** & \multicolumn{2}{c}{**23 Hours**} & \multicolumn{2}{c}{**2 Hours**} & \multicolumn{2}{c}{**6 Hours**} & \multicolumn{2}{c}{**Average**} \\ \cline{2-9}  & **G1** & **G2** & **G1** & **G1** & **G1** & **G2** & **G1** & **G2** \\ \hline
1 & 15.49 & 14.46 &  
The 25(OH)D changes in the blood samples obtained from each animal at the designated time intervals are shown in Figure 6.  
Figure 6a shows the 25(OH)D content of the experimental and control groups at 23:00, 2:00, and 6:00 h at differences of 0.71, 0.328, and 0.183 ng/mL, respectively. However, the results of Day 7 showed 0.827 ng/mL at 23:00 h, 1.045 ng/mL at 2:00 h, and 1.036 ng/mL at 6:00 h, resulting in a larger difference than that on the start date. Moreover, the results on Day 14 showed differences of 0.808 ng/mL at 23:00 h, 1.003 ng/mL at 2:00 h, and 0.898 ng/mL at 6:00 h. From these results, we confirmed that the test group (G1) had a higher 25(OH)D synthesis than the control group (G2) when kept under the test lighting. It was found that UVB-LED general light, which safely provides UVB light indoors, could increase the amount of vitamin D synthesis in an animal's body.