Quantification of chemical constituents of selected hylocereus species and their anti-inflammatory activities through inhibition of cytokines production in THP-1 cells

Abstract

Hylocereus species had been known to exhibit anti-oxidative property and has potential anti-inflammatory property as it is able to heal wound of colitis in mice. This research aims to focus on quantification of the potential anti-inflammatory chemical constituents present using high-performance liquid chromatography (HPLC) and determine the antiinflammatory activities of extracts through inhibition of cytokines. In the extraction phase, H. costaricensis and H. undatus were peeled and blended with 80% ethanol in order to get the crude extract. H. costaricensis yielded 485.5 g flesh and 39.2 g peel crude extracts while H. undatus yielded 262 g flesh and 28 g peel crude extracts. Crude extract was then taken to undergo successive extraction starting with hexane, followed by ethyl acetate and butanol. Yield for hexane, ethyl acetate, butanol and aqueous fractions for H. costaricensis flesh were 0.4 g, 1.7 g, 11.1 g and 148.3 g, respectively, while for H. costaricensis peel were 0.5 g, 0.4 g, 1.1g and 17.4 g, respectively. Yield for hexane, ethyl acetate, butanol and aqueous fractions for H. undatus flesh were 0.01 g, 0.4 g, 11.3 g and 101.4 g, respectively, while for H. undatus peel were 0.4 g, 0.1 g, 0.8 g and 14.3 g, respectively. These extracts were then analysed in order to quantify the chemical constituents present by using HPLC. Using isocratic elution, H. costaricensis flesh hexane fraction, HCF (Hex) was found to contain 0.21% of β-amyrin and 1.34% of campesterol. H. costaricensis peel hexane fraction, HCP (Hex): 0.59% of β-amyrin and 2.83% of campesterol while H. undatus peel hexane fraction, HUP (Hex): 0.15% of β-amyrin and 1.86% of campesterol. Another analysis using gradient elution showed that H. costaricensis flesh ethyl acetate fraction HCF (EA) was found to contain 0.0021% of gallic acid while H. costaricensis peel ethyl acetate fraction HCP (EA): 0.0052% of gallic acid, 0.024% of caffeic acid, 0.34% of rutin and 0.021% of quercetin. H. undatus flesh ethyl acetate fraction, HUF (EA): 0.035% of gallic acid and 0.24% of rutin while H. undatus peel ethyl acetate fraction, HUP (EA): 0.023% of gallic acid, 1.67% of rutin and 0.060% of quercetin. HUP (Hex) was found to contain 0.015% of quercetin. Anti-inflammatory activities of the extracts, fractions and selected compounds through inhibition of cytokines production were also evaluated. Results showed that both HCP (Hex), HUP (Hex) and dexamethasone (positive control) were active in inhibiting production of IL-1β in LPS induced THP-1 cells with IC50 of 105.17 μg/mL, 5.73 μg/mL and (1.2394 ± 0.0008) × 10-4 μg/mL, respectively. IL-6 was also inhibited by both fractions with IC50 of 116.3 μg/mL, 76.6 μg/mL and (3.097 ± 0.195) × 10-4 μg/mL, respectively. In general, both selected species of Hylocereus are found to be sources of bioactive phenolic acids and flavonoids which have great potential as anti-inflammatory agent.