Proximate and mineral compositions of Samia cynthia ricini and Dytiscus marginalis, commonly consumed by the Bodo tribe in Assam, India

Abstract

Background Entomophagy, the consumption of insects, is a common practice among various tribal communities across the globe. Various factors such as flavour, nutrient content, availability and claimed medicinal values have contributed to the increased consumption of insects. Two commonly consumed insects among the Bodo tribe in Assam, namely, Samia cynthia ricini Boisduval, 1854 (Lepidoptera: Saturniidae) and Dytiscus marginalis Linnaeus, 1758 (Coleoptera: Dytiscidae), were procured from local markets in Kokrajhar and evaluated for their proximate and mineral contents using Association of Official Analytical Chemists (AOAC) guidelines and inductively coupled plasma-optical emission spectroscopy (ICP-OES). Both the insects are available throughout the year and are consumed on a large scale. Results S. cynthia ricini showed higher contents of moisture (7.89 ± 0.020%), ash (4.10 ± 0.077%), fat (22.23 ± 0.209%) and carbohydrate (7.78 ± 0.057%) whereas higher contents of crude fibre (14.28 ± 0.102%), protein (56.37 ± 0.366%) and nitrogen (9.02 ± 0.058%) were observed in D. marginalis. The calorific value of S. cynthia ricini was higher with 430.19 ± 2.241 kcal whereas D. marginalis showed a lower value of 382.58 ± 1.527 kcal. D. marginalis showed the presence of arsenic (As) (0.014 ppm), and sodium (Na) was not detected. S. cynthia ricini did not show the presence of As and magnesium (Mg). Lead (Pb) showed a value of 0.026 and 0.044 ppm, and cadmium (Cd) showed a value of 0.005 and 0.005 ppm in S. cynthia ricini and D. marginalis respectively. Conclusions Both the studied insects showed high protein and fat contents and a high calorific value. Although the insects show the presence of several essential minerals in considerable amounts, they showed the presence of toxic heavy metals in trace amounts. Hence, their consumption must be done in a controlled manner owing to the presence of As, Pb and Cd which are capable of causing adverse reactions in its consumers.

Proximate Composition, Fatty Acid Profile, and Microplastic Contamination of Edible Odonate Larvae (Aeshnidae: Anax sp.) in Rice Fields

“…The macronutrient (protein and fat) composition in these edible insects reflects their gross energy value, which is also influenced by other factors, e.g., sex (Kulma et al, 2019), life stages (Ghosh et al, 2021), and diet (Oonincx and Finke, 2021). The total energy content was 360.52 Kcal/100 g and was similar to that found in the great diving beetle (Dytiscus marginalis) (Choudhury et al, 2020). However, the obtained energy values for Anax sp.…”

Tessaratoma javanica and Coridius singhalanus in the practice of entomophagy in Nagaland: an assessment of their nutritional quality

“…Interestingly, they also reported the presence of toxic elements (As, Pb, and Cd) in them, which could serve as indicators of pollution or anthropogenic activities. Likewise, Choudhury et al (2020) also assessed silk moth and diving beetle and reported high Mg, Na, Ca, Mg, Na, and K contents.…”

Nutrient composition and bioaccumulation of an edible aquatic insect,Pantalasp. (Odonata: Libellulidae) from the rice field

“…Nasirian and Irvine [18] reported Pb and Cd levels in Pantala flavescens larvae (Odonata: Libellulidae) from the Shadegan and Hawr Al Azim wetlands that were similar to those in Table 5, though our Cd levels were higher. Furthermore, Choudhury et al [5] discovered trace amounts of toxic heavy metals in the edible aquatic insect Dytiscus marginalis (Coleoptera: Dytiscidae). Local bioavailability, such as heavy metals from streams and sediments, could be one explanation.…”

“…Entomophagy is practiced in almost every country, including Africa, Asia, and Australia [3]. According to studies, insects are a good source of protein, fat, carbohydrates, and other nutrients [4][5]. Aquatic insects are one of the most popular types of entomophagy among consumers, owing to their taste and widespread availability [6].…”