Bioactive rich extracts from Terminalia ferdinandiana by enzyme-assisted extraction: A simple food safe extraction method

Abstract

A food grade compatible enzyme assisted extraction (EAE) technique for extracting bioactive compounds from freeze-dried Kakadu plum puree was evaluated. To optimise the extraction, a central composite rotatable design (CCRD) was conducted and effects of solvent concentration, enzyme concentration and time of reaction on extracted levels of free ellagic acid (fEA), ascorbic acid (AA) and total phenolic content (TPC) were determined. In the extracts, concentration of fEA ranged from 53.6 to 266.6 mg/100 g dry weight (DW) of Kakadu plum puree; AA 63.7 to 112.1 mg/100 g DW and TPC levels of 73.23 to 104.74 mg of gallic acid equivalent (GAE)/g. Extraction yield of fEA ranged from 10.3 to 51.3%. The model was found to be suitable for extraction of fEA -an important bioactive compound with documented antimicrobial properties from Kakadu plum fruit. A solvent (propylene glycol) concentration of 1.5% (w/w), enzyme (pectolytic enzymes) concentration of 300 mg/L and extraction time of 15 h was ascertained as optimum for the fEA extraction delivering a yield of 51.3%. The extraction method described here facilitates the provision of a simple, cost effective food-grade compatible extract that by-passes the need for organic solvents thereby obtaining an EA-rich aqueous extract with enhanced biological activities. This simple extraction method can also be applied to other EA rich plant material like pomegranate and peel of many common fruits which are generated as food processing by-products and can be easily adopted by numerous industries.Key words: Central composite rotatable design, ellagic acid, enzyme assisted extraction, Kakadu plum fruit, Terminalia ferdinandiana. INTRODUCTIONA species of Terminalia endemic to Australia -Terminalia ferdinandiana Exell, Combretaceae, commonly known as Kakadu plum, has a significant history as a food source and traditional medicine by the Australian aboriginal *Corresponding author. E-mail: mridusmita.chaliha@uqconnect.edu.au. Tel: (617) 3276-6007. Fax: (617) 3276-9591.Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License population for centuries. Fruits are consumed to cure headaches and to alleviate the symptoms of colds and flu while the pounded fruit is used as an antiseptic and a soothing balm for aching limbs (Konczak et al., 2010). Kakadu plum grows across large areas of Australia: Western Australia, to the south of Broome and Northern Territory, near the Arnhem Land and the Gulf area in the east, covering a range of environmental conditions (Wrigley, 1988).Kakadu plum is a rich source of polyphenolic compounds for example ellagic acid (EA) and its hydrolysable tannin, ellagitannin (Konczak et al., 2014;Williams et al., 2014). EA and its derivatives are present at high levels in many Terminalia plants (Pfundstein et al., 2010) and are reported to be responsible for their perceived health promoting and biological activities (Dhanani et al., 2015). Konczak et al. (2014) reported free EA (...

Interactions Between Phytochemicals and Minerals in Terminalia ferdinandiana and Implications for Mineral Bioavailability

“…Terminalia ferdinandiana (Kakadu plum) is a native Australian fruit consumed by Indigenous communities for centuries. In recent years, T. ferdinandiana has been established as a rich source of antioxidants and other biologically active compounds (1)(2)(3). Commercial demand for T. ferdinandiana fruit continues to increase because of its high vitamin C content (2).…”

Bioassay Guided Fractionation Protocol for Determining Novel Active Compounds in Selected Australian Flora

“…Ferulic acid isolated from Ferula foetida , which is a perennial herb, has shown anticancer activity against various types of cancers such as colon and lung cancer, and central nervous system tumors previously [ 27 ]. Additionally, studies have also demonstrated cytotoxicity of flavonoids against cancer cells and have found them to also have high free radical scavenging activity [ 28 ]. Purified flavonoids have shown anticancer activities against a number of human carcinomas which include hepatoma (Hep-G2), cervical carcinoma (Hela), and breast cancer (MCF-7) [ 28 ].…”

“…Additionally, studies have also demonstrated cytotoxicity of flavonoids against cancer cells and have found them to also have high free radical scavenging activity [ 28 ]. Purified flavonoids have shown anticancer activities against a number of human carcinomas which include hepatoma (Hep-G2), cervical carcinoma (Hela), and breast cancer (MCF-7) [ 28 ].…”