Box-Behnken Design (BBD)

Abstract

Box-Behnken design (BBD) was employed to optimize the EtOH concentration (X1: 40-80 %), liquid-to-solid ratio of (X2: 10-30 mL/g) and sonication time (X3: 30-50 min) to obtain the maximum recovery of extraction yield (YE), total phenolic content (TPC), total flavonoids content (TFC) and DPPH and ABTS radical scavenging activities from edible Asystasia gangetica leaves. The obtained second-order polynomial model provided an adequate fitting of the experimental data (p < 0.05) with regard to the responses. Response surface analysis showed that 61.48% of EtOH concentration, 21.70 mL/g of liquid-to-solid ratio and 43.41 min of sonication time were significantly maximize the responses. Under this optimum extraction conditions the experimental

In the traditional medicinal system this plant was used for the treatment of various ailments like rheumatism, stomach pains, heart pains, swellings, worms, asthma and helminthiasis (Kirtikar, & Basu, 1953; Sethuraman, & Vigneswari, 1998; Akah, Ezike, Nwafor, Okoli, & Enwerem, 2003; Kanchanapoom, & Ruchirwat, 2007) and contain a myriad of pharmacological properties such as anti-asthmatic (Akah et al., 2003), anti-microbial (Sudhakar, Rao, Rao, Raju, & Venkateswarlu, 2006), antidiabetic (PradeepKumar, Sujatha, MohamedSaleem, Madhusudhanachetty, & Ranganayakulu, 2010), anticancer (Stewart, Boonsiri, Puthong, & Rojpibulstit, 2013) antioxidant (PradeepKumar et al., 2010; Stewart et al., 2013), angiotensin

The extraction efficiency, phenolic content and bioactivity of the plant materials are greatly influenced by several factors, such as the chemical nature of the sample, particle size, nature of solvent used, solvent concentration, extraction time, pH, temperature and solid-to-liquid ratio (Cacace & Mazza 2002; Ilaiyaraja et al., 2015; Luthria, 2008; Pompeu, Silva, & Rogez, 2009; Prasad et al., 2011; Gan & Latiff, 2011; Haminiuk, Maciel, Plata-Oviedo, & Peralta, 2012). With these extraction parameters, various conventional and novel extraction methods also influence the extraction of plant polyphenols. Ultrasound-assisted extraction (UAE) is a simple and successful method used for the extraction of plant polyphenols and it has advantages over the conventional and other advanced methods which include inexpensive, environmental friendly, low energy, less solvent consumption and extraction time and high quality productivity of bioactive compounds with its preserved functional properties (Wong Paz et al., 2015; Prakash Maran, Manikandan, Thirugnanasambandham, Nivetha, & Dineshs, 2013; Chen et al., 2007). Therefore, it is necessary to optimize the extraction parameters with the suitable extraction technique to acquire maximum phenolic content recovery and