Phenolic content and antioxidant activity of selected Ugandan traditional medicinal foods

Abstract

Twenty one (21) traditional food plants recognized as medicinal by communities in Kamuli and Gulu districts in Uganda were identified and analyzed for their phytochemical content and antioxidant activity. The total phenolic content (2.6 ± 0.1 to 184.2 ± 6.4 mg GAE gDW-1) and flavonoid content (0.3 ± 0.1 to 162.2 ± 3.5 mg CE gDW-1) as well as antioxidant activity (0.1 ± 0.1 to 57.8 ± 0.5 mg VCE gDW-1) varied widely among the food plants. The seeds of Tamarindus indica L. and leaves of Ipomea eriocarpa R.Br., Corchorus trilocularis L., Ocimum suave L., Corchorus olitorius L., Acalypha bipartita Müll.Arg., and Hibiscus acetosella Welw. ex Hiern showed the highest phenolic contents and antioxidant activities. Juice prepared from tamarind pulp alone or mixed with tamarind seed powder (0.5, 1 and 3%) and analyzed for sensory acceptability, phenolic content and anti-oxidant activity were found to be highly acceptable, recording an overall hedonic acceptability scores of 7.40 ± 0.4, 6.65 ± 0.3, 7.01 ± 0.1 and 5.34 ± 0.2, respectively on a nine-point scale for juice containing 0, 0.5, 1 and 3% seed powder. Incorporation of tamarind seed powder into tamarind pulp juice resulted in a dose dependent increase in antioxidant activity from 8.5 ± 0.2 mg VCE 100 ml-1 for the control to 12.05 ± 0.3, 15.33 ± 0.7 and 17.22 ± 0.7 mg VCE 100 ml-1 for tamarind juice containing 0.5, 1 and 3% seed powder, respectively. A similar trend was recorded for the total phenolic and flavonoids.

Effects of Cooking and Drying on the Total Phenolic, Total Flavonoid Content, Antioxidant and Antibacterial Activity of Cleome gynandra (Spider Plant)

“…Boiled sample filtrate resulted in the lowest TFC of 15.85 ± 1.49 mg QE/100 g whereas the Blanched sample had the highest TFC of 446.11 ± 28.53 mg QE/100 g. The Duncan multiple range test shows that all sample's TFC means were significantly different from each other. The raw sample depicted a TFC of 71.55 ± 12 mg QE/100 g which is comparable to the results of [14] who recorded a value of 0.648 ± 0.25 mg QE/g. The analysis of the effects of cooking and drying on the TPC and TFC of the raw C. gynandra indicated that the levels of these compounds could be improved after cooking and drying.…”

“…The boiled sample exhibited a decrease in DPPH and FRAP activity at 4.34 % and 0.58 % respectively in comparison to the raw sample. The ABTS and DPPH results of the raw sample are comparable to that of [14] who reported 155. 87 µM TEAC/g and 81.109 µM QEAC/g for ABTS and DPPH respectively.…”

“…It has been utilised traditionally to treat stomach aches, headaches [11], ear diseases [12], food poisoning, rheumatism, sexual asthenia, antibacterial infections and snake bites [13]. Some studies have also shown its ability to act as an antioxidant [14], [15], [13], [16], [10], [4] while some have shown its antibacterial properties [17], [18]. Such health benefits could be attributed to its phenolic composition that has been reported in earlier studies [13], [19], [20], [21], [22], [23].…”

Effect of tamarind (Tamarindus indica L.) seed on antioxidant activity, phytocompounds, physicochemical characteristics, and sensory acceptability of enriched cookies and mango juice

“…Tamarind seed is a rich source of phytochemicals (Tsuda et al. ; Andabati and Muyonga ) which consists of phenolic antioxidants, such as 2‐hydroxy‐3′,4′‐dihydoxyacetophenone, methyl 3, 4‐dihydroxybenzoate, 3,4‐dihydroxyphenyl acetate and epicatechin (Sudjaroen et al. ; El‐Siddig et al.…”

Comparison of metabolic profiles and bioactivities of the leaves of three edible CongoleseHibiscusspecies

“…Carotenoids were also reported in the leaves of hibiscus species (Raju et al 2007). Beside, some coloured compounds car interfere at specific wavelengths of DPPH, leading to the underestimated antioxidant activity of extracts (Arnao 2001), Previous studies reported that extracts from parts of Hibiscus species such calyx of H. sabdariffa exhibited high scavenging activity (Sarkar et al 2014) and the leaves of studied Hibiscus have shown a better DPPH scavenging activity (Andabati and Muyonga, 2014; Wang et al 2014). Isolated caffeoyl-hydraxycitric acid and neochlorogenic acid, exhibited higher scavenging activities than the extracts but lower than gallic acid, used as positive control.…”