ABSTRACT
Introduction: Both kenaf (Hibiscus cannabinus) and roselle (Hibiscus sabdariffa) belong to the Malvaceae family. Method: In this study, the phytochemical analysis and anti-inflammatory activity of kenaf seed oil (KSO), kenaf seed extract (KSE), roselle seed oil (RSO) and roselle seed extract (RSE) were investigated. Results:The flavonoids content present in the roselle seed oil (RSO), roselle seed extract (RSE), kenaf seed oil (KSO) and kenaf seed extract (KSE) ranged from 52.94±7.31 mg catechin/100g of sample (KSE) to 290.05±12.04 mg catechin/100 g of (RSE); phenolic content ranged from 108.46±6.40mg GAE/ 100g of sample (RSO) to 229.65±7.91 mg GAE/ 100g of sample (RSE); saponin content ranged from 68.14±3.46 mg saponin/ 100 g of sample (KSO) to 98.50±2.44 mg saponin/ 100g of sample (RSE); terpenoid content ranged from 148.76±9.69 mg linaloo1/100g of sample (KSO) to 294.74±16.14 mg linaloo1/100g of sample (RSE); and alkaloid content ranged from 17.40±1.346%/g (KSO) to 46.95±1.792%/g (RSE). The results showed that KSE, RSO and RSE significantly inhibited (p<0.05) inflammation compared to the control. Conclusion: The present study demonstrates that KSE, RSO and RSE exhibit potent anti-inflammatory property and offer potential for use as a therapeutic regiment in managing inflammatory conditions.
ABSTRACT
Introduction: In order to overcome the stability problems of oils and fats, synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butyl hydroquinone (TBHQ) have widespread use as food additives in many countries. Recent reports reveal that these compounds may be implicated in many health risks, including cancer and carcinogenesis. Hence, there is a move towards the use of natural antioxidants of plant origin to replace these synthetic antioxidants. Methods: In this study, roselle seed oil (RSO) and extract (RSE) were mixed with sunflower oil, respectively to monitor degradation rate and investigate antioxidant activity during accelerated storage. Results: The antioxidant activity was found to stabilise sunflower oil of various samples and in the order of RSE>RSO>tocopherol>sunflower oil. The total percentage increased after 5 days of storage period in free fatty acid (FFA), peroxide value (PV) and anisidine value (AV). Total oxidation value (TOx) of sunflower oil supplemented with 1500 ppm RSE was 33.3%, 47.7%, 14.5%, and 45.5%, respectively. While the total percentage increased under different analysis methods, sunflower oil supplemented with 5% RSO was 17.2%, 60.4%, 36.2% and 59.0% in the order of FFA, PV, AV and TOTOX. Both RSO and RSE were found to be more effective in stabilisation of sunflower oil compared to tocopherol. Total phenolic content of RSE was 46.40 ± 1.51 mg GAE/100g of oil while RSO was 12.51 ± 0.15 mg GAE/100g of oil. Conclusion: The data indicates that roselle seed oil and seed extract are rich in phenolics and antioxidant activities and may be a potential source of natural antioxidants.