Australian Honeypot Ant (Camponotus inflatus) Honey-A Comprehensive Analysis of the Physiochemical Characteristics, Bioactivity, and HPTLC Profile of a Traditional Indigenous Australian Food

Abstract

Despite its cultural and nutritional importance for local Aboriginal people, the unusual insect honey produced by Western Australian honeypot ant (Camponotus inflatus) has to date been rarely investigated. This study reports on the honey's physicochemical properties, its total phenolic, major sugars and 5-hydroxymethylfurfural contents, and its antioxidant activities. The honey's color value is 467.63 mAU/63.39 mm Pfund, it has a pH of 3.85, and its electric conductivity is 449.71 µSiemens/cm. Its Brix value is 67.00, corresponding to a 33% moisture content. The total phenolics content is 19.62 mg gallic acid equivalent/100 g honey. Its antioxidant activity measured using the DPPH* (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing-antioxidant power) assays is 1367.67 µmol Trolox/kg and 3.52 mmol Fe⁺²/kg honey, respectively. Major sugars in the honey are glucose and fructose, with a fructose-to-glucose ratio of 0.85. Additionally, unidentified sugar was found in minor quantities.

Keywords: Aboriginal food; antioxidant activity; high-performance thin-layer chromatography; insect honey; physicochemical properties; sugar content.

Figure 1

Australian honeypot ants’ posterior (dorsal) side view (A) and anterior (ventral) side view (B).

Figure 2

E. Ulrich and her sister Margorie Stubbs (A) collecting honeypot ants (B) about 50 km east of the city of Kalgoorlie in Western Australia’s Goldfields region (C).

Figure 3

HPTLC images taken at white light after derivatization with aniline–diphenylamine–phosphoric acid reagent; Track 1—standards (fructose, maltose, sucrose, and glucose in increasing Rf values), Track 2—2 µL, Track 3—3 µL, Track 4—5 µL, Track 5—10 µL, and Track 6—15 µL of aqueous methanolic ant honey solution.

Figure 4

HPTLC images taken at 254 nm after development; Track 1, 2, 3, 4, and 5 were HMF (Rf 0.83) standard solution 1 µL, 2 µL, 3 µL, 4 µL, and 5 µL, respectively; Track 6, 7, and 8–10 µL aqueous ant honey solution.

Figure 5

HPTLC images taken at (a) 254 nm, (b) 366 nm, (c) white light, and (d) 366 nm after derivatization with vanillin reagent; Track 1—4,5,7-trihydroxyflavanon, Track 2—5 μL, Track 3—10 μL, and Track 4—15 μL ant honey extract.

Figure 6

HPTLC images taken at transmission white (T white) light at 60 min after derivatization with 0.4% DPPH reagent; Track 1–5—Gallic acid (Rf 0.29) 2 µL, 3 µL, 4 µL, 5 µL, and 6 μL standards in methanol; Track 6—5 μL, and Track 7—10 μL ant honey extract.