- Title
- Characterisation of the Tuckeroo (Cupaniopsis anacardioides) fruits and investigation of their phytochemicals and anti-cancer potential
- Creator
- Pham, Ngoc Minh Quynh
- Relation
- University of Newcastle Research Higher Degree Thesis
- Resource Type
- thesis
- Date
- 2020
- Description
- Research Doctorate - Doctor of Philosophy (PhD)
- Description
- Presently, many cancers are still incurable, and this is especially so at advanced stages when cancer cells metastasise throughout the body. Development of anti-cancer drugs is primarily dependent on natural products, their structures and bioactivity, however only 10% of available species have been screened for their potential as anti-cancer therapeutic agents. As such, it is necessary to investigate the anti-cancer potential from other plant materials. Tuckeroo (Cupaniopsis anacardioides) fruits, which are a rich source of bioactive compounds, were selected as the materials for the current study with the aim to characterise Tuckeroo fruits and investigate their phytochemicals, antioxidant properties and anti-cancer potential. To achieve this overall aim, this study (1) characterised the physical, phytochemical and antioxidant properties of Tuckeroo fruits; (2) investigated optimal conditions for pre-treatment and the extraction of phytochemicals and antioxidant capacity of Tuckeroo fruits; and finally, (3) evaluated the anti-cancer potential in vitro of Tuckeroo fruit extracts and their fractions. Tuckeroo fruits were found to have a spherical shape with a diameter ranging from 17- 20 mm and the weight of approximately 3.2 gram. The fresh fruits have a moisture content of 70%. Skin accounts for over 77% of the total fruit weight and has the highest levels of total phenolic content (TPC: 151.36 mg GAE/g), total flavonoid content (TFC: 95.94 mg CAE/g), and total proanthocyanidin content (TPro: 164.86 mg CAE/g). The seed and flesh account for 23% of the total fruit weight and they possessed significantly lower levels of TPC, TFC and TPro as compared to those within skin. This study comparatively evaluated the impact of a range of drying methods including freeze drying, microwave drying, vacuum drying, hot air drying and sun-drying to find the optimal conditions for pre-treatment of Tuckeroo fruits. The results showed that all five drying methods significantly affected the physicochemical and antioxidant properties of the fruits. Freeze drying was the best drying method for pre-treatment as it retained the highest TPC (81.88 mg GAE/g), TFC (107.71 mg CAE/g), TPro (83.86 mg CAE/g) and exhibited the strongest antioxidant capacity. Vacuum drying at 65 kPa, 100 °C for 5 h was the second-best pre-treatment method as it also retained high levels of TPC, TFC and TPro (58 mg GAE/g, 91 mg CAE/g and 74 mg CAE/g, respectively). This study also studied the impact of different solvents; including water, methanol, methanol 50%, ethanol, ethanol 50%, acetone, and acetone 50%, on phytochemical and antioxidant properties of Tuckeroo fruits, and found that acetone 50% was the best extraction solvent. This study applied ultrasound-assisted extraction (UAE) for extraction of phenolic compounds and antioxidant properties from the Tuckeroo fruits. The results showed that ultrasonic temperature and time, sample-to-solvent ratio and acetone concentration significantly affected extraction yields of TPC, TFC, TPro, as well as antioxidant capacity. The optimised UAE extraction conditions were found to be 50°C, 60 min, 2:100 g/mL, and 60% acetone. The crude extracts prepared from fresh and dried Tuckeroo contained fourteen major compounds, in which catechin was identified as one of these major compounds. Both powdered crude extracts and its semi-purified fractions exhibited cytotoxic properties against ten selected cancer cell lines; including HT29 (colon); U87, SJ-G2 (glioblastoma); MCF-7 (Breast); A2780 (ovarian); H460 (lung); A431 (skin); Du145 (prostate); BE2-C (neuroblastoma); and MIA PaCa-2 (pancreas) cells. Among these, extract prepared from the fresh skin using 50% acetone (SF-A50) and the butanol fraction exhibited the strongest anti-cancer activities, revealing the anti-cancer potential of the Tuckeroo fruits. Future studies are recommended to further isolate and identify major bioactive compounds from the Tuckeroo fruit materials for further testing for their anti-cancer properties.
- Subject
- Tuckeroo fruits; phytochemicals properties; anti-cancer; characterisation; Cupaniopsis anacardioides; thesis by publication
- Identifier
- http://hdl.handle.net/1959.13/1460962
- Identifier
- uon:46076
- Rights
- Copyright 2020 Ngoc Minh Quynh Pham
- Language
- eng
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | ATTACHMENT01 | Thesis | 12 MB | Adobe Acrobat PDF | View Details Download | ||
| View Details Download | ATTACHMENT02 | Abstract | 487 KB | Adobe Acrobat PDF | View Details Download |