## 3 Results and Discussion
### Comparison of Bioactive Components
#### 3.3.2. Tocopberols, Squalene, and Polyphenols  
The contents of tocopherols, squalene, and total polyphenols among different types of camellia oils were compared, as depicted in Figure 4a. Tocopherols, renowned for their antioxidant properties, can be categorized into four forms, including \(\alpha\)-, \(\beta\)-, \(\gamma\)-, and \(\delta\)-tocopherol [3]. Interestingly, only \(\alpha\)-tocopherol was identified in the six types of camellia oils examined in the present study, which is consistent with the findings of [PERSON] et al. [31], who also exclusively detected \(\alpha\)-tocopherol in seven varieties of camellia oils, with concentrations ranging from 112.8 to 257.8 mg/kg. The highest content of tocopherols was observed in C.O (260.50 mg/kg), followed by C-C.O (192.50 mg/kg) and C.G (160.00 mg/kg), with a significant difference (\(p<0.05\)) noted between them. It is noteworthy that no tocopherols were detected in C-C.O-DAG (80%) compared with C-C.O, implying that tocopherols may degrade due to the high temperature of molecular distillation during the preparation of DAG-enriched camellia oil from C-C.O [16]. Indeed, [PERSON] et al. [51] have demonstrated that heating led to a reduction in tocopherol levels, with tocopherol changes dependent on the type of oil and the duration of heating. Additionally, a small amount of tocopherols was detected in C-C.O-DAG (40%), probably because C-C.O-DAG (40%) was obtained by mixing C-C.O and C-C.O-DAG (80%) in a specific ratio. A study demonstrated that camellia oil (138.28 mg/kg) has a comparatively high squalene content compared to other edible oils, such as soybean oil (80 mg/kg) and rapeseed oil (30 mg/kg) [3]. In this study, the squalene content in C.O, C.G, C.S, and C-C.O ranged from 104.50 mg/kg to 185.50 mg/kg, aligning with earlier findings reporting squalene levels in camellia oil between 110 and 295 mg/kg [20]. Notably, C.G exhibited the highest squalene content (185.50 mg/kg), significantly surpassing other camellia oil  
Figure 4: Comparison of tocopherols, squalene, and total polyphenols in different types of camellia oil (**a**), and cluster heat map with tocopherols, squalene, and total polyphenols in different types of camellia oil as variables (**b**). Mean values with different letters in are significantly different from each other at \(p<0.05\). C.O, _C. oleifera_; _C.S_, _C. semiseratta_); C.G, _C. gauchowensis_; C-C.O, commercial _C. oleifera_; C-C.O-DAG (40%), commercial _C. oleifera_ diacylglycerolglycerol oil (40%); and C-C.O-DAG (80%), commercial _C. oleifera_ diacylglycerolglycerol oil (80%). types (C.O, C.S, and C-C.O; 104.50-110.50 mg/kg) (Figure 4a), highlighting the influence of camellia oil variety on the squalene content. Moreover, DAG-enriched camellia oils (C-C.O-DAG) showed very low squalene contents, indicating an impact from both the variety and processing techniques on squalene levels. Polyphenols are known for their health benefits, including antioxidant properties [10]. According to their chemical structure, polyphenols can be categorized into catechins, flavonoids, anthocyanins, and phenolic acids [2]. To date, 24 phenolic compounds have been identified from camellia oil, including 13 phenolic acids (i.e., benzoic acid, p-hydroxybenzoic acid, protocatechuric acid, gallic acid, phthalic acid, p-hydroxyphenylacetic acid, vanillic acid, cinnamic acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, and chlorogenic acid), 4 catechins (i.e., catechin, epicatechin, epigallocatechin, and epigallocatechin gallate), and 7 flavonoids (i.e., apigenin, kaempfer, luteolin, quercetin, myricetin, naringenin, and taxifolin) [20; 52]. Notably, benzoic acid (2.95-18.87 mg/kg), vanillic acid (1.63-17.64 mg/kg), cinnamic acid (3.72-16.69 mg/kg), and naringenin (0.16-10.77 mg/kg) collectively contribute to more than half of the total polyphenol content, highlighting their contribution to the nutritional value and shelf life of camellia oil [20; 52].