Date fruits are well known to be very nutritious. Nevertheless, the protein contents of the fruit, particularly the seed and flesh, are still understudied, largely due to their difficult physical characteristics. This study was conducted to compare three different protein extraction methods which were the trichloroacetic acid (TCA)-acetone (TCA-A), phenol (Phe), and TCA-acetone-phenol (TCA-A-Phe), and to perform proteomic analysis on date palm seed and flesh. Phe extraction method showed the highest protein yields for both seed (8.26 mg/g) and flesh (1.57 mg/g). Through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Phe, and TCA-A-Phe extraction methods were shown to be efficient in removing interfering compounds and gave well-resolved bands over a wide range of molecular weights. Following liquid chromatography-tandem mass spectrometry analysis, about 50-64% of extracted proteins were identified with known functions including those involved in glycolysis, Krebs cycle, defense, and storage. Phe protein extraction method was proven to be the optimal method for date flesh and seed.

No abstract

Onnia tomentosa is a widespread root rot pathogen frequently found in coniferous forests in North America. In this study, the potential medicinal properties of this wild polypore mushroom collected from north–central British Columbia, Canada, were investigated. The ethanol extract from O. tomentosa was found to exhibit strong antiproliferative activity. Liquid–liquid extraction and bioactivity-guided fractionation, together with HPLC-MS/MS and 1D/2D NMR analyses of the ethanol extract of O. tomentosa, led to the identification of eight known linoleic oxygenated fatty acids (1.1–1.4 and 2–5), together with linoleic (6) and oleic acids (7). The autoxidation of linoleic acid upon isolation from a natural source and compound 5 as an autoxidation product of linoleic acid are reported here for the first time. GC-FID analysis of O. tomentosa, Fomitopsis officinalis, Echinodontium tinctorium, and Albatrellus flettii revealed linoleic, oleic, palmitic, and stearic acids as the major fatty acids. This study further showed that fatty acids were the major antiproliferative constituents in the ethanol extract from O. tomentosa. Linoleic acid and oleic acid had IC50 values of 50.3 and 90.4 µM against human cervical cancer cells (HeLa), respectively. The results from this study have implications regarding the future exploration of O. tomentosa as a possible edible and/or medicinal mushroom. It is also recommended that necessary caution be taken when isolating unstable fatty acids from natural sources and in interpreting the results.

The ethanol extract of the fungus Sarcodon scabripes collected from north-central British Columbia, Canada, showed strong antiproliferative activity. Bioassay-guided purification using liquid-liquid extraction and Sephadex LH-20 size-exclusion chromatography followed by HPLC-MS and 1D/2D NMR analyses, led to the isolation of five known compounds; four p-terphenyl (1-4) derivatives and one phenolic aldehyde (5).Compounds 1, 4, and 5 were isolated for the first time from the Sarcodon genus. The cytotoxicity MTT assay showed that compounds 1-5 have antiproliferative activity against human cervical cancer cells (HeLa). For compounds 1-4, this is the first report of their antiproliferative activity against cancer cells. For compound 2, this is the first report on its bioactivity. To our knowledge, this is the first description on the isolation of bioactive constituents from S. scabripes.

Small molecules, including synthetic and those isolated from natural products, are important classes of compounds with broad utility, including drugs. The objectives of this dissertation were (i) to synthesize, purify, and characterize novel small molecule inhibitors on KRAS expression level; (ii) to purify and characterize antiproliferative small molecules from Onnia tomentosa and Sarcodon Scabripes.The first part of this Ph.D. dissertation focuses on synthesizing dispiropyrrolidizine derivatives with potential KRAS protein expression inhibitory activity. At the outset of this study, compound UNBC 152, which turned out to be a mixture of compounds, was found to possess bioactivities including antiproliferative activity and the ability to inhibit KRAS expression. This study aimed to synthesize UNBC 152 and resolve the compound-activity ambiguity. The investigation on UNBC 152 led to the isolation of two novel regioisomers, 6 and 7. Regioisomers 6 and 7 were synthesized using a one-pot three-component 1,3-dipolar cycloaddition reaction.They were purified using recrystallization method and their structures were determined by FTIR, ESI-LRMS, NMR, and X-ray crystallography. Regioisomers 6 and 7 showed the ability to inhibit KRAS protein expression.Over the past several decades, researchers have isolated many useful medicinal compounds from mushrooms. Medicinal mushrooms with validated anticancer properties in animals have been found and this has encouraged further exploration of fungal metabolites with antiproliferative activity. The second part of this Ph.D. dissertation focuses on isolating antiproliferative small molecules from two species of mushrooms native to British Columbia (BC). Chapters 3 and 4 described the use of antiproliferative activity-guided approach that led to the isolation and structural elucidation of small molecules from O. tomentosa and S. scabripes native to Northern iii BC. The ethanolic extracts of O. tomentosa and S. scabripes were purified using phase separation, Sephadex LH-20, and HPLC-based fractionation. The final structure of the small molecules was determined by ESI-LRMS, ESI-HRMS/MS, and NMR. Fatty acids (labeled 1.1-1.4 and 2-7) were identified from the ethanolic extract of O. tomentosa, while several p-terphenyl derivatives (1-4) and one phenolic aldehyde (5) were identified from S. scabripes. Amongst the small molecules, oleic acid (7), linoleic acid (6), and linoleic degradation products from O. tomentosa, and compounds 1-5 from S. scabripes showed antiproliferative activity against HeLa cervical cancer cells. iv PREFACE This Ph.D. dissertation yielded one published manuscript for Chapter 2, while the manuscripts for Chapters 3 and 4 are currently under revision and review, respectively. Publication and authorships from this dissertation were stated as follows (Published or under review):