In addition, it is also believed that okra fruits possess various bioactivities, such as anti-hyperlipidemic , antioxidant [5,6], anti-hyperglycemic , and neuroprotective activities . radical scavenging capacity, 2,2-azino-bis (3-ethylenzthiazoline-6-sulphonic acid) radical scavenging capacity, and ferric reducing antioxidant power) and inhibitory effects on digestive enzymes (lipase, -glucosidase, and -amylase). Indeed, Shuiguo exhibited much better antioxidant activities and inhibitory activities on digestive enzymes, which might be attributed to its high TFC. Results suggested that okra, especially Shuiguo, could be developed as natural antioxidants and inhibitors against hyperlipidemia and hyperglycemia in the fields Mef2c of functional foods and pharmaceuticals, which could meet the increasing demand for high-quality okra with health-promoting properties in China. L. Moench), native to Africa, has been cultivated and used as food and folk medicine around the world due to its health-promoting benefits [1,2]. Various cultivars of okra fruits have also been cultivated widely in China, including cv. Wuxing, cv. Kalong 3, cv. Kalong 8, cv. Wufu, cv. Royal red, and cv. Shuiguo . It is commonly considered that okra fruits can prevent diabetes and obesity [2,4]. In addition, it is also believed that okra fruits Daphnetin possess various bioactivities, such as anti-hyperlipidemic , antioxidant [5,6], anti-hyperglycemic , and neuroprotective activities . Generally, polysaccharides and phenolic compounds are referred to the major bioactive components in okra fruits, which are also the sources of its various biological activities . Generally, polysaccharides and their bioactivities are influenced by different cultivars of okra fruits whether in China or abroad [3,10]. Previous study has reported that the content of phenolics and flavonoids are significantly different in different cultivars of okra collected in Greece, and their antioxidant activities may be also influenced by different cultivars . At present, growing evidence has documented that the content of phenolics can directly influence the digestive enzymes, which participate in the hydrolyzation Daphnetin of fats and carbohydrates in our daily diet . However, the determination and comparison of phenolic compounds in different cultivars of okra cultivated in China and the correlations among phenolic compounds, antioxidant activity, anti-hyperlipidemic activity, and anti-hyperglycemic activity have seldom been investigated. Furthermore, qualitative and quantitative analysis of phenolic compounds in different cultivars of okra fruits is also important and necessary for the evaluation of their biological characteristics [13,14]. Thus, it is necessary to evaluate and compare the phenolic compounds and their bioactivities of different cultivars of okra fruits collected in China, so as to meet the increasing demand for high-quality vegetables with health-promoting properties in China. In this study, in order to properly understand the phenolic compounds and their bioactivities of different cultivars of okra fruits collected in China, the phenolic profiles, antioxidant capacities, and inhibitory effects on digestive enzymes of five representative cultivars of okra fruits collected in China, including Kalong 3, Kalong 8, Shuiguo, Wufu, and Royal red, were systematically evaluated and compared. 2. Results and Discussion 2.1. Phenolic Compounds in Different Cultivars of Okra Fruits Phenolic compounds are considered as one of the major bioactive components in okra fruits [2,5]. Therefore, phenolic compounds in different cultivars of okra fruits cultivated in China were investigated. The contents of total flavonoids (TFC) of the five representative okra fruits collected in China were determined and presented in Table 1. Significantly different levels (< 0.05) of TFC were detected in Shuiguo (3.39 mg RE/g DW), compared to Kalong 3 (3.22 mg RE/g DW), Kalong 8 (3.03 mg RE/g DW), Wufu (2.94 mg RE/g DW), and Royal red (1.75 mg RE/g DW). Results showed that the TFC changed significantly among the five okra fruits, which was similar to previous studies [15,16]. In fact, the phenolic profiles of plants are directly affected by extrinsic and intrinsic factors, such as cultivar, maturity, and environmental conditions . The interaction of these factors will influence the metabolism of plants, and then lead to produce different bioactive compounds, such as different type of phenolic compounds . Table 1 Contents of total flavonoids (TFC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH), 2,2-azino-bis (3-ethylenzthiazoline-6-sulphonic acid) radical scavenging Daphnetin capacity (ABTS), and ferric reducing antioxidant power (FRAP) of different cultivars of okra fruits. < 0.05. Thus, a total of six phenolic compounds were investigated in the okra fruit based on previous studies, including catechin, isoquercitrin, protocatechuic acid, quercetin, quercetin-3-O-gentiobioside, and rutin [2,15,18]. Figure 1A and Figure 1B showed the high-performance liquid chromatography (HPLC) chromatograms of the six mixed standards, and Figure 1C and Figure 1D showed the individual phenolic compounds in the representative cultivar (Shuiguo) of okra fruit. Results showed that five phenolic compounds, including isoquercitrin (UV max, 245 nm and 355 nm), protocatechuic acid (UV max, 260 nm and 293 nm), quercetin (UV max, 255 nm and 365.