The Effect of Dietary Vitamin C on Carbohydrate Concentrations and Hydrolase Activity, During the Development of Honey Bee Worker Brood

Abstract

A b s t r a c t The colony collapse disorder is a growing problem world-wide. For this reason, we were prompted to search for natural and harmless agents that could improve the living conditions of honey bees. This group of agents includes exogenous antioxidants, such as ascorbic acid, which boost natural immunity. We analysed the effect of vitamin C supplementation on carbohydrate metabolism in the developing honey bee worker brood. The total carbohydrate content and the concentrations of glycogen, trehalose, maltotriose, fructose, and glucose were estimated. The correlations between sugar content and the activity of the main hydrolases of carbohydrate metabolism -α-amylase, glucoamylase, trehalase, maltase, and sucrase -were determined. The addition of vitamin C to the diet of wintering bees did not impair their sugar metabolism. Vitamin C supplements exerted a positive effect by signifi cantly increasing glycogen and trehalose concentrations in the initial phase of development and in newly emerged workers. Vitamin C did not induce signifi cant changes in the developmental profi le of carbohydrate degrading enzymes, except for the earliest stage of larval development when enzyme activity levels were below those noted in the control group.

Supplementing With Vitamin C the Diet of Honey Bees Parasitized With Varroa destructor: Effect on Carbohydrate Metabolism

“…Carbohydrate metabolism in newly-emerged bees was not significantly different between C and AA colonies. Those results corroborate our previous findings relating healthy brood (Farjan et al, 2015). Vitamin C supplementation in both healthy and infested capped brood (Table 2) did not induce significant changes in total carbohydrate content relative to the control group ( Figure 1A).…”

“…Similar observations were made in A. mellifera drones infested with V. destructor (Żółtowska et al, 2007). In newly emerged worker bees from group C trehalose concentrations was determined at 0.93±0.04 mg/100 mg BW in infested bees and 0.70±0.18 mg/100 mg BW in uninfested bees (see Farjan et al, 2015). Moreover, trehalose level were significantly higher in infested workers from group AA than in group C bees ( Figure 1B).…”

“…Total carbohydrate content was determined by the anthrone method (Morse, 1947), and glycogen concentrations -by the method proposed by Sölling and Essman (1975). Trehalose, sucrose, glucose and fructose content was measured by high-performance liquid chromatography (HPLC) in accordance to the method described by Farjan et al (2015). The results were expressed in terms of mg per 100 mg of fresh body weight (BW).…”

“…The supplementation reduced winter losses and the severity of varroasis in the analyzed population. Ascorbic acid strengthened the antioxidant system, increased body weight and protein level in newly hatched bees (Andi & Ahmadi, 2014;Farjan et al, 2012Farjan et al, , 2015.…”

“…Carbohydrates are the main source of energy for bees (Blatt & Roces, 2001;Hrassing & Crailsheim, 2005;Broschneider & Crailsheim, 2010), and therefore the effect of vitamin C on carbohydrate metabolism in healthy bees was also studied (Farjan et al, 2015). The parameters of carbohydrate metabolism were compared in infested bees whose diet was and were not supplemented with vitamin C. In the following stage of the study, we investigated whether with vitamin C would have a similar effect on colonies naturally infested with V. destructor.…”