Optimizing the Extraction of Polysaccharides from Bletilla ochracea Schltr. Using Response Surface Methodology (RSM) and Evaluating their Antioxidant Activity

Abstract

Bletilla ochracea Schltr. polysaccharides (BOP) have a similar structure to Bletilla striata (Thunb.) Reichb.f. (Orchidaceae) polysaccharides (BSP). Therefore, BOP can be considered as a substitute for BSP in the food, pharmaceuticals and cosmetics fields. To the best of our knowledge, little information is available regarding the optimization of extraction and antioxidant activity of BOP. In this study, response surface methodology (RSM) was firstly used for optimizing the extraction parameters of BOP. The results suggested that the optimal conditions included a temperature of 82 °C, a duration of 85 min and a liquid/material ratio of 30 mL/g. In these conditions, we received 26.45% ± 0.18% as the experimental yield. In addition, BOP exhibited strong concentration-dependent antioxidant abilities in vitro. The half-maximal effective concentration (EC50) values of BOP against 1,1-diphenyl-2-picrylhydrazyl (DPPH·), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonate) (ABTS+·), hydroxyl (·OH) and superoxide anion (·O2−) radicals and ferrous ions (Fe2+) were determined as 692.16, 224.09, 542.22, 600.53 and 515.70 µg/mL, respectively. In conclusion, our results indicate that BOP can be a potential natural antioxidant, deserving further investigation.

Screening of Bletilla striata, Bletilla ochracea and Oreorchis foliosa differential metabolites based on metabolomics

“…BSP) yields, as evidenced by different reports, where the experimental result from Qu et al was 43.95% (Qu, Li, Zhang, Zeng, & Fu, 2016) in contrast to that of Wang et al, which was only 10% (Wang et al, 2019). Once our research team optimized the extraction strategy using the response surface method, the BOP yield also increased to 26.45% (Wang et al, 2020).…”

“…Numerous research results have shown that the active components of B. striata are primarily polysaccharides (BSPs) (Chen, Cheng, He, & Wei, 2018; Peng, Xue, & Liu, 2014; Wang, Li, Qiao, & Di, 2018), which comprise glucose and mannose in a certain molar ratio (Kong et al, 2015; Wang, Liu, et al, 2014; Wang, Zhang, et al, 2014). The BSPs have clinically relevant procoagulant (Ding et al, 2017), antiviral (Shi et al, 2017), antioxidant (Qu, Li, Zhang, Zeng, & Fu, 2016; Song et al, 2017; Wang et al, 2020) and immunoregulatory activity (Chen, Cheng, He, & Wei, 2018; Wang et al, 2019), and antitumor properties (Guan et al, 2016; Qian et al, 2003). Simultaneously, medical supplies have been developed that are based on the biological characteristics of BSP, which play important roles in medicine (Hu, Liao, Hu, Maffucci, & Qu, 2018; Wang et al, 2017).…”

“…Our previous experimental results for B. ochracea polysaccharides (BOP) revealed that they were composed of two simple sugars (glucose and mannose) that had antioxidant and immune system‐enhancing effects (Niu, Wang, et al, 2020; Niu, Zhao, et al, 2020; Wang et al, 2020). However, there exist limited data on the polysaccharides of O. foliosa (OFP) as relates to their structures and bioactivities.…”

“…Therefore, it remains uncertain whether the content and composition of polysaccharides might be employed as key indicators to completely distinguish the three species described above. Despite polysaccharide analysis, which plays a key role in the authentication of several Chinese herbal medicines (Chen et al, 2012; Lai et al, 2018; Wang et al, 2020). B. striata contains additional small molecules such as bibenzyls (Jiang et al, 2019), phenanthrenes (Guo et al, 2017), stilbenes, ethers (Guo et al, 2017; Masae et al, 1992) and anthocyanins.…”

Synthesis, characterization, and antioxidant activity in vitro of selenium-Euryale ferox Salisb. polysaccharide

“…Moreover, R 2 (0.9879), AdjR 2 (0.9764), and Adeq precision (> 4) indicated the high fitting degree of the model. The low value of C.V.% (7.16) showed the high accuracy and reliability of the model [33]. F value (6.44) and P value (0.0817) of lack of fit suggested the few variations between the actual and predicted values [34].…”