Nutritional Composition of Five Soil-Dwelling Scarab Beetles (Coleoptera: Scarabaeidae) of Assam, India

Proximate and elemental compositions of five soil-dwelling scarabs, Lepidiota mansueta Burmeister, Lepidiota albistigma Burmeister, Xylotrupes gideon (Linnaeus), Catharsius molossus (Linnaeus), and Sophrops iridipennis (Brenske), were assessed. Nutrient content varied widely, and the ranges of proximate contents were as follows: moisture (2.04–2.55%), crude protein (68.54–79.33%), crude fat (4.00–5.50%), crude fibre (5.16–8.28%), total mineral (0.80–4.98%), and carbohydrate (5.28–11.84%). Caloric content was greater in L. mansueta (379.29 kcal) compared to the other four species. The caloric contents of X. gideon (375.54 kcal) and C. molossus (375.19 kcal) were at par but significantly higher than those of L. albistigma (371.04 kcal) and S. iridipennis (361.55 kcal). Sodium content ranged 23.16–35.91 mg/100 g; potassium 14.20–44.33 mg/100 g; calcium 23.33–33.37 mg/100 g; iron 1.41–37.05 mg/100 g; copper 2.01–16.13 mg/100 g; zinc 2.38–15.86 mg/100 g; and manganese 1.09–19.66 mg/100 g. The phenol, flavonoid, and antioxidant activities of L. mansueta and L. albistigma were 4.00 and 6.42 mg catechol equivalent/g, 1.59 and 3.71 mg quercetin equivalent/g, 22.60, and 28.20%(DPPH activity), respectively. Tannin content was higher in L. albistigma (13.30 mg/g) than in L. mansueta (3.24 mg/g). Based on our study, these scarab species can be explored as food supplements and nutraceutical resources in ensuring food security.