Pearce, Keenau Mark2026-06-122026-06-122020https://hdl.handle.net/10566/24427Introduction Typha capensis (T. capensis), commonly known as bulrush, is a medicinal plant found growing in the wetland areas of South Africa. In traditional medicine, rhizome decoctions of T. capensis are used to treat a wide variety of ailments, including venereal disease, dysentery, diarrhoea and low libido in men. Previously, T. capensis rhizomes were shown to be a rich source of antioxidants, such as catechin and epicatechin, inhibiting both reactive oxygen species and reactive nitrogen species. The antioxidant capacity of such plant species serves as a reservoir of electrons to transport them into gold salt for the production of gold nanoparticles through green nanotechnology. Therefore, this study aimed to investigate the application of T. capensis in green nanotechnology and nano-medicine. Material and methods This study investigated the synthesis of gold nanoparticles (AuNP’s) from two aqueous T. capensis extracts, the S1 and S2 extracts, along with the bioactive compound naringenin. The following parameters were used for AuNP characterisation: spectrophotometry, dynamic light scattering, zeta potential, transmission electron microscopy (TEM), Folin-ciocalteu phenol assay, inductively coupled plasma mass spectrometry (ICP-MS). Hereafter, the effects of these AuNP’s were investigated toward the LNCaP and PC-3 prostate cancer, Panc1 pancreatic cancer, and HAEC human aortic endothelial cell lines over 24, 48 and 72 hours. Additionally, possible AuNP cell internalisation was investigated in the LNCaP and PC-3 cells by dark field hyperspectral microscopy, and definitive AuNP-cell internalisation in PC-3 cells by TEM imaging. Finally, selected AuNP’s, along with the S1 extract and naringenin, were investigated in vivo using SCID-mice bearing PC-3 prostate cancer tumour xenografts. Results Aqueous T. capensis rhizome extracts produced AuNP’s in a single step reaction, yielding the S1-AuNP’s, S1x2-AuNP’s, S2-AuNP’s and S2x2-AuNP’s. Similarly, the isolated bioactive compound naringenin also produced AuNP’s when the reaction was controlled at pH 7 and pH 8, yielding the Ng-AuNPs pH 7 and Ng-AuNP’s pH 8. These particles proved to be highly stable, showing no agglomeration over time. The extracts, naringenin, and their subsequent AuNPs yielded comparable levels of toxicity toward the LNCaP cells at each time point. Compared to the S1 extract, the S1-AuNP’s yielded significantly (P=0.0001, P=0.0004, P<0.0001) greater reduction in PC-3 cell viability at the highest concentration used, over each time point. Similarly, the highest concentration of the S2-AuNP’s produced significantly (P=0.0319, P=0.0006, P=0.0003) greater reductions in PC-3 cell viability at each time point in comparison to the S2 extract. The highest concentration of the Ng-AuNP’s pH 8 were also found to yield significantly (P=0.0009, P=0.0002, P=0.0125) greater reductions in PC-3 cell viability over each time point. The S1-AuNP’s, S1x2-AuNP’s, S2-AuNP’s, S2x2-AuNP’s, NgAuNP’s pH 7 and Ng-AuNP’s pH 8 yielded improved toxicity toward Panc1 cells in both a dose- and time-dependent manner. However, each AuNP formulation, along with their extract or bioactive compound counterpart, produced a degree of dose and time-dependent toxicity toward the non-cancerous HAEC cell line. Under in vivo conditions, the S1 extract and S1-AuNP’s were well tolerated by SCID-mice bearing PC-3 prostate cancer tumour xenografts, with 1.5 mg/kg of the S1-AuNPs significantly (P=0.0027) inhibiting tumour growth by the end of the study. Additionally, 1.5 mg/kg of the S1-AuNP’s yielded a significantly (P=0.0339) lowered neutrophil to lymphocyte ratio by the end of the study. Similarly, naringenin at a dose of 0.5 mg/kg, and the Ng-AuNPs pH 8 at 0.5 and 1.5 mg/kg significantly (P=0.0038, P=0.0038, P=0.006) inhibited tumour growth, and greatly improved bodyweight by the end of the study. Conclusion In summary, the collected data showthat highly stable gold nanoparticles, encapsulated with a plethora of phytochemicals from both Typha capensis and the bioactive compound naringenin, have been synthesized through a single step process. These nanoparticles exhibited robust stability under in vitro conditions and clear signs of cell internalisation, observed using darkfield microscopy and TEM. When compared to the effects of the extracts, similar levels of toxicity were observed in the case of the LNCaP and PC-3 cells. However, these nanoparticles were found to yield improved toxicity toward Panc1 cells in both a dose- and time-dependent manner. Furthermore, the present study demonstrated for the first time the positive therapeutic effects of T. capensis extract toward prostate cancer under in vivo conditions, adding a degree of validity to its clinical usage suggested by Ilfergane (2016). However, these positive effects were not found to be improved, nor maintained, by nano-encapsulation of the extract. The NgAuNP’s, however, were able to maintain the anti-cancer effects of free naringenin under in vivo conditions, having favourable outcomes toward tumour growth, body weight and blood parameters in tumour-bearing SCID-miceenTypha capensis (T. capensis)CytotoxicityViabilityQuercetinNaringeninThesis