Acute toxicity study and prevention of Nω-nitro-L-arginine methyl ester-induced hypertension by Osteopermum imbricatum

Purpose: To determine the phytochemical content, toxicity and hypertension prevention effects of Osteospermum imbricatum leaf and root extracts.Methods: Phytochemical screening of leaf and root extracts of O. imbricatum was performed by colorimetric procedure. Acute toxicity of leaf and root extracts was conducted in two phases; phase I consisted of three groups of mice (n = 3) for each dose level of 10, 100 and 1000 mg/kg while phase II had three mice that received 1600, 2900 or 5000 mg/kg. Wistar rats were grouped into 7 groups that were co-treated with L-NAME and normal saline or L-NAME and hydroethanolic leaf extract (150 and 300 mg/kg) or L-NAME and hydroethanolic root extract (150 and 300 mg/kg) or L-NAME and amlodipine (5 mg/kg) or normal saline only for 4 weeks. Treatment was carried out via the oral route while blood pressure was measured weekly for 4 weeks by non-invasive tail cuff method.Results: The phytochemical profile of the leaf and root extracts revealed the presence of phenols, terpenoids, flavonoids, glycosides, tannins, steroids and saponins. Both the leaf and root extracts were toxic at 5000 mg/kg with an LD50 of 3807.89 mg/kg. In the fourth week of the study, only the leaf extract significantly (p < 0.01) prevented the progression of L-NAME induced hypertension; systolic and diastolic blood pressure of the group treated with L-NAME and leaf extract (300 mg/kg) were 183 ± 1 and 140 ± 1 mmHg, respectively, compared to the group that was treated with L-NAME and normal saline which produced systolic and diastolic BP values of 213 ± 3 and 172 ± 4 mmHg, respectively. The extracts, especially OIR300, exhibited diuretic effects in the second and third week of study by promoting excretion of 16 and 19 ml urine, respectively, compared to 11 and 14 ml for LN group.Conclusion: The results suggest that O. imbricatum is moderately toxic at a high dose and contains a wide range of phytochemicals which offer partial protection against the development of nitric oxide deficiency hypertension.Keywords: Hypertension, Phytochemicals, Acute toxicity, Nω-Nitro-L-arginine methyl ester (L-NAME), Osteospermum imbricatu

Acute toxicity study and prevention of Nω-nitro-L-arginine methyl ester-induced hypertension by Osteopermum imbricatum

Purpose:To determine the phytochemical content, toxicity and hypertension prevention effects of Osteospermum imbricatum leaf and root extracts.Methods:Phytochemical screening of leaf and root extracts of O. imbricatum was performed by colorimetric procedure. Acute toxicity of leaf and root extracts was conductedin two phases; phase I consisted of three groups of mice (n = 3) for each dose level of 10, 100 and 1000 mg/kg while phase II had three mice that received 1600, 2900 or 5000 mg/kg. Wistar rats were grouped into 7 groups that were co-treated with L-NAME and normal saline or L-NAME and hydroethanolic leaf extract (150 and 300 mg/kg) or L-NAME and hydroethanolic root extract (150 and 300 mg/kg) or L-NAME and amlodipine (5 mg/kg) or normal saline only for 4 weeks. Treatment was carried out via the oral route while blood pressure was measured weeklyfor 4 weeks by non-invasive tail cuff method.Results:The phytochemical profile of the leaf and root extracts revealed the presence of phenols, terpenoids, flavonoids, glycosides, tannins, steroids and saponins. Both the leaf and root extracts were toxic at 5000 mg/kg with an LD50of 3807.89 mg/kg. In the fourth week of the study, only the leaf extract significantly (p less 0.01) prevented the progression of L-NAME induced hypertension; systolic and diastolic blood pressure of the group treated with L-NAME and leaf extract (300 mg/kg) were 183 ± 1 and 140 ± 1 mmHg, respectively, compared to the group that was treated with L-NAME and normal saline which produced systolic and diastolic BP values of 213 ± 3 and 172 ± 4 mmHg, respectively. The extracts, especially OIR300, exhibited diuretic effects in the second and third week of study by promoting excretion of 16 and 19 ml urine, respectively, compared to 11 and 14 ml for LN group.Conclusion:The results suggest that O. imbricatum is moderately toxic at a high dose and contains a wide range of phytochemicals which offer partial protection against the development of nitric oxide deficiency hypertension

Acute toxicity study and prevention of Nω-nitro-L-arginine methyl ester-induced hypertension by Osteopermum imbricatum

Purpose:To determine the phytochemical content, toxicity and hypertension prevention effects of Osteospermum imbricatum leaf and root extracts.Methods:Phytochemical screening of leaf and root extracts of O. imbricatum was performed by colorimetric procedure. Acute toxicity of leaf and root extracts was conductedin two phases; phase I consisted of three groups of mice (n = 3) for each dose level of 10, 100 and 1000 mg/kg while phase II had three mice that received 1600, 2900 or 5000 mg/kg. Wistar rats were grouped into 7 groups that were co-treated with L-NAME and normal saline or L-NAME and hydroethanolic leaf extract (150 and 300 mg/kg) or L-NAME and hydroethanolic root extract (150 and 300 mg/kg) or L-NAME and amlodipine (5 mg/kg) or normal saline only for 4 weeks. Treatment was carried out via the oral route while blood pressure was measured weeklyfor 4 weeks by non-invasive tail cuff method.Results:The phytochemical profile of the leaf and root extracts revealed the presence of phenols, terpenoids, flavonoids, glycosides, tannins, steroids and saponins. Both the leaf and root extracts were toxic at 5000 mg/kg with an LD50of 3807.89 mg/kg. In the fourth week of the study, only the leaf extract significantly (p less 0.01) prevented the progression of L-NAME induced hypertension; systolic and diastolic blood pressure of the group treated with L-NAME and leaf extract (300 mg/kg) were 183 ± 1 and 140 ± 1 mmHg, respectively, compared to the group that was treated with L-NAME and normal saline which produced systolic and diastolic BP values of 213 ± 3 and 172 ± 4 mmHg, respectively. The extracts, especially OIR300, exhibited diuretic effects in the second and third week of study by promoting excretion of 16 and 19 ml urine, respectively, compared to 11 and 14 ml for LN group.Conclusion:The results suggest that O. imbricatum is moderately toxic at a high dose and contains a wide range of phytochemicals which offer partial protection against the development of nitric oxide deficiency hypertension

Effect of mould temperature on the filling behavior of molten resin in plastic injection moulding of high density polyethylene (HDPE)

CITATION: Gwebu, A. M., et al. 2014. Effect of mould temperature on the filling behavior of molten resin in plastic injection moulding of high density polyethylene (HDPE). In SAIIE26 Proceedings, 14–16 July 2014, Muldersdrift, South Africa.The original publication is available at http://conferences.sun.ac.za/index.php/saiieENGLISH ABSTRACT: The growth of injection moulding as a manufacturing process has led to the development of more products resulting in an increase in the focus on product quality, as manufacturers try to lower production costs, reduce product weight and eliminate defects. Of particular concern is the flow behavior of molten resin in the mould cavities during the production process. Inconsistencies in the flow of the melt tend to result in uneven or incomplete filling of the mould, resulting in production of defects (short shots). In the paper the Taguchi method is used to determine the optimum values of the injection moulding process parameters for High Density Polyethylene (HDPE.) plastic parts. A moulding processing window in which the process will achieve maximum quality, with major focus being on mould filling is developed.AFRIKAANSE OPSOMMING: Geen opsomming beskikbaarhttp://conferences.sun.ac.za/index.php/saiie/SAIIE26/paper/view/1167Publisher's versio

Science first - Contributions of a university-industry toxic substances research and teaching program to economic development

Public policy establishing the UC Toxic Substances Research and Teaching Program helped to establish the state's environmental technology industry. The multidisciplinary "science-push" program generated economic development benefits including leveraged research funding and at least two hundred new private sector jobs, twenty-five spin-off companies, and over one hundred patents