UWCScholar :: Browsing by Author "Syce, James A."

Browsing by Author "Syce, James A."

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Acute and chronic toxicity of the flavonoid-containing plant, Artemisia afra in rodents
(University of the Western Cape, 2005) Mukinda, James Tshikosa; Syce, James A.; School of Pharmacy; Faculty of Community and Health Sciences
The aim of this study was to investigate the possible toxicity of the flavonoid-containing plant, Artemisia afra and especially establish the safety of the aqueous extract of this plant after acute and chronic administration to mice and rats respectively.
The chemical stability of betamethasone valerate and fluocinolone acetonide cream and ointment in cetomacrogol and emulsifying cream and ointment bases
(University of the Western Cape, 2002) Titus, Michael John; Syce, James A.
The corticosteroids are powerful anti-inflammatory molecules but their usage is hampered by adverse effects. To minimise their adverse reactions, proprietary brands of topical corticosteroids are commonly diluted with a variety of bases. Dilution may affect the stability of the corticosteroid molecule and may result in accelerated degradation. This degradation may vary depending on the diluent base used. Such dilutions are also made in the Western Cape Department of Health public health system where unique formulations of cetomacrogol and emulsifying preparations are used as diluents. Because of the uncertainty of how these diluents would affect the steroid molecules, no accurate expiry dates could be allocated to the diluted preparations. This study set out to determine the chemical stability of betamethasone valerate and fluocinolone acetonide creams and ointments when diluted with the bases used in the public hospital system and to assign shelf lives to them. Samples of the branded topical corticosteroid products used by the Western Cape Department of Health were diluted 1 :10 and 50:50 with cetomacrogol and emulsifying cream and ointment bases. The diluted preparations were stored protected from light, moisture and air at 25'C. Samples of the preparations were assayed at intervals for their corticosteroid content using reverse phase High Performance Liquid Chromatography. These concentrations of corticosteroid provided a degradation profile of each preparation from which degradation rate constants were determined and shelf lives calculated. The HPLC method used was sensitive, accurate and specific for the active ingredients studied. The retention times of betamethasone valerate and fluocinolone acetonide were 4,00 and 5,15 minutes respectively. Betamethasone valerate was significantly more stable in the cream dilutions than in the ointment dilutions (e g. 1 .10 dilution in cetomacrogol cream t* = 5,46 +- months vs 1 :10 dilution in cetomacrogol ointment tgo = 1 ,62 +- months P = 0,0181 ). Conversely, fluocinolone acetonide was more stable in the ointment dilutions than in the cream dilutions but not significantly so (e.9. 1:10 dilution in cetomacrogol ointment tgo = 12,69 +- months vs 1 :10 dilution in cetomacrogol cream tro = l,$! +- months P = 0,1938). ln general, both corticosteroids degraded more slowly when diluted with cetomacrogol cream (e.9. 1 :10 dilutions of betamethasone valerate cream tro = 5,46 +- months and fluocinolone acetonide cream teo= 2,63 +- months) than with emulsifying cream (e.g. 1 :10 dilutions of betamethasone valerate cream tno = 3,05 +- months but not significantly so P = 0,8280 and fluocinolone acetonide cream tro= 0,0111 +- months extremely significantly so P<0,0001) and more slowly when diluted with cetomacrogol ointment (e g. 1 :10 dilutions of betamethasone valerate ointment tso = 1 ,62 +- months and fluocinolone acetonide ointment tso = 12,69 +- months) than with emulsifying ointment (e.g. 1 :10 dilutions of betamethasone valerate ointment t* = 0,18 +- months and fluocinolone acetonide ointment 1 .10 t* = 9,81 +- months although not significantly so P = 0,6590). Also, generally, the more concentrated dilutions were more stable than the more dilute ones (e.g 50:50 dilution of betamethasone valerate in cetomacrogol ointment tro = 4,33 +- months vs 1:10 dilution tgo = 1,62 months significantly so P = 0,0140 and 50:50 dilution of fluocinolone acetonide in cetomacrogol ointment t* = 46,90 +- months vs 1:10 dilution tro = 12,69 +- months although not significantly so P = 0,6005). Due to the rapid breakdown of the molecules it is therefore recommended that 1 :10 dilutions of betamethasone valerate ointment not be made using emulsifying ointment nor should branded products of fluocinolone acetonide be diluted with emulsifying cream at all. The calculated shelf lives should be used as a guide when the various combinations of steroids and diluents are to be used.
A comparative study of the phosphodiesterase 4 inhibitory activity of artemisia afra, Leonotis leonorus and mentha longifolia plant medicines
(University of the Western Cape, 2007) Mulubwe, Ngosa.; Syce, James A.; Faculty of Science
The specific objectives of this study were to investigate whether Artemisia Afra, Leonotis leonorous and Mentha Longiflora have PDE 4 inhibitory activity, to determine and compare the levels of the total phenolic compunds , total and individual flavanoids, especially luteolin and hesperetin, in the three plants and finally, to determine if there was a correlation between the PDE inhibitory activity and the levels of flavanoids or phenolic compounds in the plants. It was hypothesized that the plants with higher levels of total flavonoid and/or aglycone luteolin and/or hesperetin had higher PDE inhibitory activity.
Comparison of the sutherlandioside B levels in two commercially available Sutherlandia frutescence preparations and the effect of elevated temperature and humidity on these levels
(University of the Western Cape, 2009) Joseph, Ashton Edward; Syce, James A.; School of Pharmacy; Faculty of Community and Health Sciences
Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune™ capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be “better” as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B); secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1™ tablet and the Promune™ capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products.
Comparison of the sutherlandioside B levels in two commercially available sutherlandia frutescens preparations and the effect of elevated temperature and humidity on these levels
(2009) Joseph, Ashton Edward; Syce, James A.
The design, preparation and evaluation of Artemisia Afra and placebos in tea bag dosage form suitable for use in clinical trials
(University of the Western Cape, 2006) Dube, Admire; Syce, James A.; School of Pharmacy; Faculty of Science
Artemisia Afra, a popular South African traditional herbal medicine is commonly administered as a tea infusion of the leaves. However, clinical trials proving it safety and efficacy are lacking mainly due to the absence of good quality dosage forms and credible placebos for the plant. The objectives of this study were to prepare a standardized preparation of the plant leaves and freeze-dried aqueous extract powder of the leaves, in a tea bag dosage form and to design and prepare credible placebos for these plant materials.
The development and evaluation of the Objective Structured Dispensing Examination (OSDE) for use in an undergraduate pharmacy training programme
(University of the Western Cape, 2004) Frieslaar, Denise Eleanor; Syce, James A.; Bheekie, Angeni; Faculty of Science
Effects of environmental growth conditions on the levels of sutherlandins 3 and 4 and sutherlandiosides B and D, in Sutherlandia frutescens (L.) R. Br.
(University of the Western Cape, 2011) Whisgary, Darryn; Syce, James A.
Sutherlandia frutescens (L.) R. Br. (Fabaceae), indigenous to the Western Cape region of South Africa, is found in a Mediterranean-type climate known for its many environmental stressors that can influence the levels of metabolites found in plants. Sutherlandia frutescens contains many known potential active constituents among them, flavonoids such as sutherlandins 3 and 4 (Su3 and Su4) and terpenoids such as sutherlandiosides B and D (SuB and SuD). Whether the profiles and levels of Su3, Su4, SuB and SuD are significantly affected by the environmental factors found in this area is however, unknown. iBatech™ is an ethanolic plant extract that is manufactured by researchers in the Department of Medical Biosciences, UWC, for use as a pesticide. HPLC analysis performed on Lycopersicon species treated with the iBatech™ product have shown that it also caused an increase in the concentrations of total polyphenols in the plant (Klaasen et.al., unpublished data). Whether the treatment with iBatech™ might also cause an increase in the polyphenols such as sutherlandins 3 and 4 and sutherlandiosides B and D is also unknown. The objectives of this study were to determine the concentrations of sutherlandins 3 and 4 (Su3 and Su4) and sutherlandiosides B and D (SuB and SuD) in S. frutescens collected from different sites and after the treatment with the iBatech™ product. The specific objectives were: a) to locate and categorize sites where S. frutescens is grown, based on a selection of pertinent environmental growth factors, b) to determine and compare the concentrations of sutherlandins 3 and 4 and sutherlandiosides B and D in S. frutescens collected from the different environmental growth sites and after treatment with the iBatech™ product. To realize these objectives, S. frutescens samples were collected from eight different sites and broadly categorized into three environmental categories. A high-performance liquid chromatography (HPLC) method using diode array ultraviolet detection (HPLC-DAD) for the simultaneous analysis of flavonoids and terpenoids was developed and validated, and used for the profiling and determination of the average levels of sutherlandins 3 and 4 and sutherlandiosides B and D in the samples from the sites and that treated with the iBatech™ product. The Kruskal-Wallis test was used to determine statistically significant differences among the environmental categories. The post ANOVA, Dunn's Multiple Comparison test was performed to determine which groups were significantly different. The Mann-Whitney, two-tail, t-test was used to compare each environmental category to the standard and the column statistics of the raw data was analyzed to determine significant differences among samples from the same environmental category. In the samples collected from the sites, the values represent the average levels of metabolites for each environmental category whereas the significance values indicated were among samples from the same environmental category. The levels for sutherlandin 3 were Afriplex™ (Std.) 2495.08, the natural field (NF) 2810.33 (P=0.0005), the cultivated field (CF) 2519.81 and the greenhouse (GH) 2580.25. The levels for sutherlandin 4 were significantly different when comparing the (NF) 1495.67 (P=0.0001), (CF) 3114.42 (P=0.0140) and (GH) 2361.72 (P=0.0001), with the CF group showing the highest levels of Su4 and the NF showing the lowest. The levels for sutherlandioside B were (NF) 189.7 (P=0.0189), (CF) 594.56 (P=0.0140) and (GH) 326.72 (P=0.0001), however, the CF group showed the highest average levels for SuB. The levels for sutherlandioside D were (NF) 144.1 (P=0.0192), (CF) 544.37 (P=0.0308) and (GH) 387.49 (P=0.0001), with the NF category having the lowest average levels. In the iBatech™ treated samples, the values indicate the average levels of three samples in each treatment group. The levels for sutherlandin 3 were (control) 9758.43, the (50%) 2232.63 and the (100%) 2031.97 treatment groups. The levels for sutherlandin 4) were (control) 2241.63, the (50%) 2247.47 and the (100%) 2392.60, with the 100% treatment group having the highest levels. The levels for sutherlandioside B were (control) 289.66, the (50%) 284.93 and the (100%) 332.30. The levels for sutherlandioside D were (control) 282.77, the (50%) 280.60 and the (100%) 315.13 treatment groups, with the 100% treatment group having the highest levels. The levels of Su3, Su4, SuB and SuD were significantly different (P=0.0001) among all treatment groups. In conclusion, the data shows that only sutherlandin 4 (Su4) was significantly different when comparing the environmental groups. Due to the significant differences in the Su3, Su4, SuB and SuD levels among samples from the same group the levels of these metabolites cannot be correlated with the environmental groups.
Effects of environmental growth conditions on the levels of sutherlandins 3 and 4 and sutherlandiosides B and D, in Sutherlandia frutescens (L.) R. Br.
(University of the Western Cape, 2011) Whisgary, Darryn; Syce, James A.
Sutherlandia frutescens (L.) R. Br. (Fabaceae), indigenous to the Western Cape region of South Africa, is found in a Mediterranean-type climate known for its many environmental stressors that can influence the levels of metabolites found in plants. Sutherlandia frutescens contains many known potential active constituents among them, flavonoids such as sutherlandins 3 and 4 (Su3 and Su4) and terpenoids such as sutherlandiosides B and D (SuB and SuD). Whether the profiles and levels of Su3, Su4, SuB and SuD are significantly affected by the environmental factors found in this area is however, unknown. iBatech™ is an ethanolic plant extract that is manufactured by researchers in the Department of Medical Biosciences, UWC, for use as a pesticide. HPLC analysis performed on Lycopersicon species treated with the iBatech™ product have shown that it also caused an increase in the concentrations of total polyphenols in the plant (Klaasen et.al., unpublished data). Whether the treatment with iBatech™ might also cause an increase in the polyphenols such as sutherlandins 3 and 4 and sutherlandiosides B and D is also unknown. The objectives of this study were to determine the concentrations of sutherlandins 3 and 4 (Su3 and Su4) and sutherlandiosides B and D (SuB and SuD) in S. frutescens collected from different sites and after the treatment with the iBatech™ product. The specific objectives were: a) to locate and categorize sites where S. frutescens is grown, based on a selection of pertinent environmental growth factors, b) to determine and compare the concentrations of sutherlandins 3 and 4 and sutherlandiosides B and D in S. frutescens collected from the different environmental growth sites and after treatment with the iBatech™ product. To realize these objectives, S. frutescens samples were collected from eight different sites and broadly categorized into three environmental categories. A high-performance liquid chromatography (HPLC) method using diode array ultraviolet detection (HPLC-DAD) for the simultaneous analysis of flavonoids and terpenoids was developed and validated, and used for the profiling and determination of the average levels of sutherlandins 3 and 4 and sutherlandiosides B and D in the samples from the sites and that treated with the iBatech™ product. The Kruskal-Wallis test was used to determine statistically significant differences among the environmental categories. The post ANOVA, Dunn's Multiple Comparison test was performed to determine which groups were significantly different. The Mann-Whitney, two-tail, t-test was used to compare each environmental category to the standard and the column statistics of the raw data was analyzed to determine significant differences among samples from the same environmental category. In the samples collected from the sites, the values represent the average levels of metabolites for each environmental category whereas the significance values indicated were among samples from the same environmental category. The levels for sutherlandin 3 were Afriplex™ (Std.) 2495.08, the natural field (NF) 2810.33 (P=0.0005), the cultivated field (CF) 2519.81 and the greenhouse (GH) 2580.25. The levels for sutherlandin 4 were significantly different when comparing the (NF) 1495.67 (P=0.0001), (CF) 3114.42 (P=0.0140) and (GH) 2361.72 (P=0.0001), with the CF group showing the highest levels of Su4 and the NF showing the lowest. The levels for sutherlandioside B were (NF) 189.7 (P=0.0189), (CF) 594.56 (P=0.0140) and (GH) 326.72 (P=0.0001), however, the CF group showed the highest average levels for SuB. The levels for sutherlandioside D were (NF) 144.1 (P=0.0192), (CF) 544.37 (P=0.0308) and (GH) 387.49 (P=0.0001), with the NF category having the lowest average levels. In the iBatech™ treated samples, the values indicate the average levels of three samples in each treatment group. The levels for sutherlandin 3 were (control) 9758.43, the (50%) 2232.63 and the (100%) 2031.97 treatment groups. The levels for sutherlandin 4) were (control) 2241.63, the (50%) 2247.47 and the (100%) 2392.60, with the 100% treatment group having the highest levels. The levels for sutherlandioside B were (control) 289.66, the (50%) 284.93 and the (100%) 332.30. The levels for sutherlandioside D were (control) 282.77, the (50%) 280.60 and the (100%) 315.13 treatment groups, with the 100% treatment group having the highest levels. The levels of Su3, Su4, SuB and SuD were significantly different (P=0.0001) among all treatment groups. In conclusion, the data shows that only sutherlandin 4 (Su4) was significantly different when comparing the environmental groups. Due to the significant differences in the Su3, Su4, SuB and SuD levels among samples from the same group the levels of these metabolites cannot be correlated with the environmental groups.
Evaluation of guidelines for clinical trials of traditional plant medicines
(University of the Western Cape, 2005) Van Wyk, Anthea; Syce, James A.; School of Pharmacy; Faculty of Community and Health Sciences
The World Health Organization estimates that 4 billion people use herbal medicine for some aspect of primary health care. These herbal products are however mostly used without the necessary clinical trial done to prove their pharmacological activities and, therefore, their quality, efficacy and safety. It was the objective of this study to review the current international guidelines for the evaluation of herbal medicine; to gain a perspective on the number, type and quality of clinical trials that have been done on herbal medicine and to adopt a set of guidelines that could be used to conduct trial on a traditional herbal medicine used in South Africa. To verify these guidelines, a protocol for a clinical trial was drafted and submitted for approval to the regulatory and ethical authorities in South Africa.
Evaluation of the antioxidant and anti-diabesity potential of cyclopia maculata using in vitro non-cell based screening models
(University of the Western Cape, 2014) Matrose, Albertina Neliswa; Syce, James A.; Joubert, E; Malherbe, C.J
The aim of this study was therefore to evaluate the antioxidant and anti-diabesity potential of a hot water extract of C. maculata in non-cell based assays and correlate the activities with phenolic composition. Total antioxidant capacity (TAC) was assessed in terms of free radical scavenging and iron reducing ability. The DPPH, ABTS, ORAC and FRAP assays were employed. Anti-diabesity potential was assessed in terms of the inhibition of the digestive enzymes, α-glucosidase and pancreatic lipase
Evaluation of the antioxidant and anti-diabesity potential of cyclopia maculata using in vitro non-cell based screening models
(University of the Western Cape, 2014) Matrose, Albertina Neliswa; Syce, James A.; Joubert, E; Malherbe, C.J
The aim of this study was therefore to evaluate the antioxidant and anti-diabesity potential of a hot water extract of C. maculata in non-cell based assays and correlate the activities with phenolic composition. Total antioxidant capacity (TAC) was assessed in terms of free radical scavenging and iron reducing ability. The DPPH, ABTS, ORAC and FRAP assays were employed. Anti-diabesity potential was assessed in terms of the inhibition of the digestive enzymes, α-glucosidase and pancreatic lipase
The formulation and evaluation of rapid release tablets manufactured from Artemisia Afra plant material
(University of the Western Cape, 2004) Komperlla, Mahesh Kumar; Syce, James A.; Bapoo, Rafik A.; School of Pharmacy; Faculty of Science
Infusions, decoctions, alcoholic preparations and other dosage forms of Artemisia afra are frequently used in South African traditional medicine. Generally when these preparations are made without applying good manufacturing practices they do not meet microbial quality control standards, safety and toxicity criteria and encourage poor patients compliance. To overcome the aforementioned disadvantages of traditional dosage forms a sold dosage form, i.e. a table might be recommended. The first objective of this study was to formulate and manufacture a rapid release tablet dosage of Artemisia afra that would contain an amount of plant material equivalent to that found in its traditional liquid dosage forms and that would meet conventional pharmaceutical standards. The second objective was to conduct a pilot study to obtain a preliminary profile of the bioavailability of select flavonoids presents in both the tablet and traditional liquid preparation of Artemisia afra in humans.
Formulation and evaluation of tablets manufactured from Dodonaea Angustifolia plant material
(University of the Western Cape, 2001) Kayitare, Egide; Syce, James A.
The liquid dosage form is the most frequently used form for traditional plant medicines. However, this dosage form is associated with many problems, e.g. physicochemical instability, microbial contamination, etc. which may be solved using a solid dosage form. This study investigates the formulation and manufacture of tablets containing two types of material prepared from the leaves of Dodonaea angustifolia. The main goal of the present study was to formulate and produce tablets containing the same amount of plant material as found in the usual dose of D. angustifolia decoction. ln addition, the suitability of using directly dried leaf powder and dried aqueous extract of the leaves, as raw material for the tablets, was compared. lt was hypothesized that tablets with acceptable physical properties and containing 80% or more of plant material could be produced and that tablets containing dry leaf powder or dry plant extract would possess different properties. Raw plant material in the form of dried leaf powder and dried aqueous extracts (Dry Extract 1 from wide leaf plant and Dry Extract 2from narrow leaf plant) of D. angustifolr3 were prepared and their physical characteristics determined. Based on the latter, suitable excipients were selected and formulas containing the same amount of the plant material as found in a single decoction dose of D. angustifolia were elaborated. Thereafter, tablets containing these plant materials were manufactured using the direct compression method and the physical properties of the manufactured tablets were assessed. Results of the pre-formulation study indicated distinct differences in physical properties between the three plant materials. The dry leaf powder had a median particle size of 20prm compared to 200pm and 3441tm for Dry Extracts 1 and 2, respectively. The dry leaf powder was significantly more soluble in ethanol than water (55.7t0.g vs. 26.1+3o/o, t-test, p=0.05), while the extracts dissolved completely but required vigorous shaking. The compressibility of the dry powder was very good (11.910.5%), that of dry extract 2 good (15.9t2.8Yo) and that of Dry Extract 1 only passable (22.6tO.8%). All the powders showed poor flowability, but they had different potentials to pick up moisture. More importantly, the dry extracts became very cohesive and tended to dissolve in the absorbed moisture at relative humidity above 60%. The tablets containing the dry leaf powder and those containing Dry Extracts 1 and 2 required different formulas and different compression forces and displayed different physical properties. The final proportions of plant material per tablet were B5o/of or dry powder,650/o for dry extract 1 and 7Oo/of or dry extract 2. Finally, all the final tablets had acceptable physical properties. However, the tablets containing the dry extracts showed slow disintegration (27.6 and 29.6min for Dry Extracts 1 & 2, respectively, vs. 3.1min for dry powder) and low dissolution rate (38.60/o and 6o.20/o al 45min for Extracts 1 and 2 vs. 92.7o/o for the dry powder). We conclude that the different forms of raw material prepared from the leaves of D. angustifotia have different properties, but can be formulated and manufactured into directly compressed tablets. However, the form of raw material dictates whether the tablets can contain a high proportion (80% plus) of plant material and also influences the properties of the final tablets. Comparable results can be anticipated if materials from other parts of the plant and/or from other plants are to be used.
The formulation, manufacture and evaluation of capsules containing freeze-dried aqueous extracts of Leonotis Leonorus or Mentha Longifolia
(University of the Western Cape, 2006) Ma, Haiqiu; Syce, James A.; School of Pharmacy; Faculty of Science
Leonotis leonorus and Mentha longifolia are two herbs commonly used in South Africa, mostly in oral liquid dosage forms. Several disadvantages are associated with these traditional dosage forms which can perhaps be remedied by using an appropriate oral solid dosage form, provided the actual plant material in the latter still resemble, as closely as possible, the traditionally used material and provide products of suitable pharmaceutical quality. The objectives of this study were to prepare and evaluate the pharmaceutical suitability of the freeze-dried aqueous extracts of Leonotis Leonorus and Mentha Longifolia as plant raw material for the capsule dosage of these two therapies and to formulate and manufacture capsules of Leonotis Leonorus and Mentha Longifolia aqueous extract that would contain amounts of the plant materials equivalent to that found in their traditional liquid dosage forms, and have immediate release characteristics and suitability stability.
Investigation of the in vitro bioavailability of luteolin from modified preparations of Artemisia afra
(University of the Western Cape, 2014) Nkengla, Anjong; Syce, James A.
Artemisia afra (A. afra) is traditionally used for a variety of ailments and contain flavonoids e.g. luteolin which may contribute to some of its activity. It is generally administered as a tea or decoction, and such liquid dosage forms present challenges as far as long term storage and stability are concerned, as well as sub-optimal oral bioavailability of actives they contain. Freeze dried aqueous extracts (FDAE) can alleviate such problems but may be hygroscopic and unstable. The use of modified forms of FDAE can counter the problem of hygroscopicity (e.g. use of alginate) and alleviate the issue of sub-optimal bioavailability of plant actives (e.g. polymethylmethacrylate). The objectives of this study, were to: (1) prepare the freeze dried aqueous extract (FDAE) and modified forms, which include alginate-extract beads (alginate-FDAE) and polymethylmethacrylate coated alginate matrix beads of herbal extract (PMMA-alginate-FDAE) of the FDAE of A. afra, (2) determine and compare the pharmaceutical characteristics of the above mentioned preparations of A. afra,(3) quantify and compare the total flavonoid and specifically luteolin levels of the different forms of A. afra,(4) evaluate and compare the release characteristics of FDAE of A. afra from the alginate-FDAE and PMMA-alginate-FDAE beads in gastrointestinal fluids and (5) determine the intestinal permeability of luteolin contained in selected modified Artemisia afra extract preparations. It was hypothesized that making the alginate beads and the polymethylmethacrylate coated alginate beads would make the FDAE less hygroscopic with a lower moisture content, that the rate of release of luteolin from A. afra FDAE into gastrointestinal fluids would be faster than from the modified forms, and that the effective gastrointestinal permeability of luteolin in the alginate-FDAE and PMMA-alginate-FDAE beads of A. afra is equal to that in FDAE. To realize these objectives, the FDAE was prepared by freeze drying the aqueous extract of the A. afra dried leaves, alginate-FDAE prepared by dispersing FDAE into 4% sodium alginate solution, then adding the resulting stock solution into a 2% calcium chloride solution and drying resulting beads and PMMA-alginate-FDAE prepared by a modified water-in-oil-in-water emulsion solvent evaporation method using water as an internal aqueous phase. Using pharmacopoeial methods and methods adapted from other workers the organoleptic and pharmaceutical characteristics were determined to compare the pharmaceutical quality of these preparations of A. afra. To identify and determine the levels of luteolin in the plant preparations, a validated HPLC assay was developed. Finally, the in situ perfused rat intestine model was used to determine the in vitro bioavailability, i.e. gastrointestinal permeability, of luteolin from solutions containing luteolin in pure form, FDAE, alginate-FDAE and PMMA-alginate-FDAE. The A. afra forms were obtained in moderate to good yields and FDAE was brown and hygroscopic in nature, the alginate beads dark brown free flowing and spherical in shape and the PMMA-alginate beads light brown in colour with rough edges. The A. afra plant forms on average contained 0.185 ± 0.24, 0.067 ± 0.014, 0.012 ± 0.071 μg/mg of free luteolin (n=3) in FDAE, alginate-FDAE and PMMA-alginate-FDAE respectively and 0.235 ± 0.026, 0.079 ± 0.093, 0.058 ± 0.082 μg/mg of total luteolin (n=3) in FDAE, alginate-FDAE and PMMAalginate- FDAE respectively. The Plumen values for intestinal uptake of luteolin were significantly higher from solutions of A. afra forms than the pure luteolin solution (i.e. Plumen values in the range of 0.02 - 0.035 cm/s for all plant forms vs Plumen values in the range of 0.010 - 0.014 cm/s for pure luteolin, t-test p = 0.0252). The permeability of luteolin in FDAE appeared to be slighter greater than that of the modified forms (Plumen values >0.03 cm/s for FDAE and Plumen values <0.03 cm/s for both modified forms). In summary, the results showed that, the modified A. afra forms; alginate-FDAE and PMMAalginate- FDAE were of acceptable pharmaceutical quality with luteolin better taken up in the plant forms than in its pure form. The A. afra forms prepared had similar rates of uptake (permeability) of free and total luteolin with the rates being highest for the FDAE. Collectively, these results indicate that alginate-FDAE and PMMA-alginate-FDAE bead forms should be suitable for use in a solid dosage form (e.g. tablet or capsule) of A. afra.
Pharmaceutical evaluation of phela capsules Used as traditional medicine
(University of the Western Cape, 2010) Sehume, Brian J.; Syce, James A.; Matsabisa, Gilbert Motlalepula; School of Pharmacy; Faculty of Community and Health Sciences
In conclusion, the results obtained firstly indicated that the BP, EMEA and WHO were in fairly good agreement on the criteria and specifications that can be used to assesses the pharmaceutical quality of a traditional plant medicine such as Phela. Secondly, the Phela plant powders were found to have acceptable pharmaceutical properties that did not complicate or adversely affected the capsule manufacture. Thirdly, the Phela capsules produced were generally of acceptable pharmacopoeial standard. Fourthly, HPLC fingerprinting and pattern recognition analysis proved useful to examine the chemical stability of selected marker compounds of Phela and indicated that the capsules had no practical shelf life under elevated temperature and humid conditions. Overall, the Phela capsules should thus be suitable for use in a short time clinical trial, but for use in a long period trial the long term stability of the Phela capsules under ambient conditions must still be confirmed.
Preparation, characterisation and evaluation of Artemisia afra phytosomes with modified release properties
(University of the Western Cape, 2017) Bepe, Nyashadzashe; Syce, James A.
Dissolution studies on various dosage forms (powder, tablets, teabags and alginate beads) of the Artemisia afra freeze dried aqueous extract (FDAE) all exhibit a rapid release profile. Generally, such a release profile may be therapeutically undesirable as it may affect absorption and hence the therapeutic outcome. In addition, also associated with rapid release profiles, is frequent dosing required (to maintain therapeutic plasma concentrations) and unavoidable fluctuations in plasma drug concentrations, leading to under and or over dosing. Based on the aforementioned shortcomings, there may be need to modify the dissolution profile of the phytoconstituents of A. afra. Phytosomes, which are complexes of phospholipids with phytoconstituents, offer a very viable dosage form option for A. afra as they could afford advantages of increased lipophilicity hence a decreased dissolution rate and improved absorption or permeability of the phytoconstituents.
The development of a study protocol, and ethics and regulatory approval documentation, for evaluation of clinical efficacy of Sutherlandia frutescens in adult type-2 diabetics
(University of the Western Cape, 2018) Swead, Ramadan; Syce, James A.
The prevalence of diabetes mellitus is increasing worldwide and it is becoming a significant medical problem in low- and middle-income countries. The condition can be controlled with a lifelong commitment to blood sugar monitoring, weight management, proper nutrition, exercise, and pharmacotherapy. Additional new pharmacotherapies are however needed to combat the increased prevalence and various traditionally used herbs, such as Sutherlandia frutescens (S, frutescens), are being advocated to supplement the management of type 2 diabetes mellitus. However, the clinical efficacy of S. frutescens in the management of type 2 diabetes mellitus has not yet been scientifically established.

Browsing by Author "Syce, James A."

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