The entomophagy or feeding on insects provides nutritional and economic opportunities. We studied the nutritional value of bee larvae harvested in the Eastern part of the Democratic Republic of Congo. Bees (Apis mellifera L.) named « Bukavu », which come from beehives set in the region of Bukavu and its surroundings (~60 km radius) in a region known traditionally as Bushi, were studied in September 2014. Bee larvae from Bukavu were compared to those available in the Province of Namur (Belgium) and larvae of the wax moth. In Belgium bee larvae were collected from local beehives whereas the larva of the greater wax moth Galleria mellonella were bought from the supermarket. Quantitative analyses of triglycerides, cholesterol, phospholipids and glucose based on specific enzymatic reactions performed. The composition (weight/dry weight) of the Bukavu larvae was made of 20.68% for lipids, 15.40% for proteins and 7.36% for glucose. That of Namur larvae was made of 13.75% for lipids, 31.94% for proteins and 18.43% for glucose. Larvae of the greater wax moth contained 40.14% for lipids, 16.7% for proteins and 0.14% for glucose. These results are equivalent to 251 kcal for the Bukavu bees, 416 kcal for Namur bees and 312 kcal for moth larvae in 100 g of dry weight samples. Mineral element composition (w/dry weight) was 3.07% for Bukavu bee larvae, 6.86% for Namur bee larvae and 2.41% for moth larvae. The nutritional value of bee larvae from Bukavu and Namur depends somehow upon their origin, the environmental conditions including the availability of melliferous plants, and other factors. We conclude that bee larvae (Apis mellifera L) and larvae of the wax moth Galleria mellonella L may be used at a large scale to fight against protein deficiency and malnutrition among the local populations in the region of Bukavu. Their production can be integrated in the management plan of Kahuzi-Biega National Park. Our results are similar to the findings published by other authors on Apis mellifera and Galleria mellonella larvae.

The polymorphism of lysosoma ß- galactosidase (EC. 3.2.1.23) and N- acetylglucosaminidase (EC. 3.2.1.49) has been established taking into account the variation of their specific activities at both the larval, pupal and adult stages. These activities have been decreased from the larva stage (22.03 ± 4.3 nmoles/min/mg of protein) to the adult stage (5.30 ± 1.27 nmoles/min/mg of protein) via the pupal stage (20.4 ± 1.78 nmoles/min/mg of protein). The N- acetylglucosaminidase activity has been about 10 times as higher as that of β-galactosidase. That activity of the N- acetylglucosaminidase is 200.88 ± 31.39 nmoles/min/mg of protein for larvae, 115.00 ± 21.02 nmoles/min/mg of protein for pupas and 9.48 ± 2.23 nmoles/min/mg of protein for adults. The activities of both 2 enzymes have followed the MICHAELIS-MENTEN law as they were positively linear as well in function of the enzyme concentration and the incubation time as in function of the substrate concentration. The temperature has influenced their respective activities according to ARRHENIUS law, the Q10 being around 2. The cathepsine C (EC. 3.4.14.1) activities have been equal to 2.03 ± 1.18, 0.95 ± 0.54 and 0.76 ± 0.39 nmoles/min/mg of protein for larvae, pupas and adults, respectively. For the acid phosphatase (EC. 3.1.3.2), the activities have been equal to 6.29 ± 2.87, 6.89 ± 2.69 and 8.51 ± 4.51 nmoles/min/mg of protein for larvae, pupas and adults, respectively. These activities are weak comparatively to those of the former two glycosidases at the 3 development stages of Apis mellifera L. Conversely, the venom acid phosphatase has been very active (25.32 ± 6.94 nmoles/min/mg of protein), an activity almost 20 times higher than that of both cathepsine C, β-galactosidase and N-acetylglucosaminidase. The β-galactosidase and N-acetylglucosaminidase from larvae and pupas have all the characteristics of lysosoma enzymes. They have a maximum activity at acidic pH, i.e. 5 for the β-galactosidase and 6 for the N-acetylglucosaminidase, and present a latency property that is annihilated by detergents. A fraction of their activity being sedimentable in the used experimental conditions, these 2 glycosidases are most likely lysosoma acid hydrolases and indicate the presence of lysosomes in Apis mellifera L. In addition, as their activities vary during the bee development stages, it becomes evident the 2 glycosidases are involved in the bee metamorphosis and are thus polymorphic in Apis mellifera L. Another enzyme, i.e. the hyaluronidase (EC. 3.2.1.35; MW 37 kDa), has been identified in the bee venom.