Oxidative stress is a major factor in the development of diseases in Apis Mellifera. To assess the functionality of the antioxidant system in bees, total antioxidant status (TAS) serves as a critical indicator. Commonly, Vitamin C is used to enhance TAS, yet its effectiveness is limited by its relatively low antioxidant activity. In this study, we synthesized tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride, offering a novel alternative to Vitamin C for TAS enhancement. Notably, previous research has not explored coordination compounds for this purpose in bees.

The cobalt(III) complex was synthesized through the reaction of cobalt(II) hexahydrate with N-(prop-2-en-1-yl)hydrazinecarbothioamide in ethanol and hydrochloric acid at 50-55°C, yielding an octahedral complex cation, where the neutral bidentate ligands facilitated the oxidation of cobalt(II) to cobalt(III) with 87% efficiency. The characterization techniques included single crystal X-ray diffraction, FT-IR, ¹H NMR, ¹³C NMR, elemental analysis, and molar conductivity. Antioxidant activity was assessed via ABTS, DPPH, and ORAC assays, while toxicity was evaluated using Daphnia magna. The complex demonstrated significant antioxidant activity, with an IC₅₀ of 7.3±0.3 µM, and lower toxicity than expected, with an LC₅₀ of 56.3±3.1 µM.

The experimental results revealed that tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride increased TAS in the hemolymph of bees and larvae by up to 5 and 8 times, respectively. The IC₅₀ values were recorded at 2.5 mg/mL for bee hemolymph and 1.3 mg/mL for larval hemolymph, compared to control values of 13.6 mg/mL and 10.0 mg/mL, respectively.

The stimulatory effect of the tested compound on TAS surpassed the activity of Vitamin C by up to 5 times.

These findings suggest that increasing TAS levels in bees could enhance their immune systems, highlighting the potential of tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]cobalt(III) chloride as a beneficial additive in apicultural health practices.

This research was funded by the subprograms 010602 and 010701.