Potential treatment of leachate by Hermetia illucens (Diptera, Stratyomyidae) larvae: Performance under different feeding conditions

Abstract

In this study, the ability of H. illucens larvae (black soldier fly (BSF)) to metabolise different semisolid biowastes (e.g. kitchen waste, animal manure) has been applied to the treatment of landfill leachate. A testing programme has been developed by mixing leachate with three different solid supports: wheat bran, a biodegradable nutrient substrate, brewers’ spent grain, a biodegradable nutrient residue from the brewery industry and sawdust, a low biodegradable residue from the wood industry. Larvae growth rate was monitored in terms of weight variation, mortality and time to reach the prepupal stage. Prepupal biomass composition was analysed in terms of crude protein, lipids and fatty acids. Substrates were monitored at the beginning and the end of tests for total solids (TS), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), ammonia and (whenever significant) the 7-day Respirometric Index (RI7). The best performance was observed with wheat bran and brewers’ spent grain, achieving an average larval weight ranging from 155.1 to 226.1 mg (w/w) with prepupation of more than 80% over 21 days. The initial TS, TOC and nitrogen content in feeding substrates had been metabolised (gasified and accumulated in prepupal biomass) by approximately 55%, 60% and 48%, respectively. Dry mass characterisation displayed a significant content of fats and proteins. The analysis demonstrated the suitability of BSF prepupal biomass for the production of biodiesel; however, the potential use of proteins as an animal feed needs further studies for assessing the presence of contaminants.

Growth Performance, Waste Reduction Efficiency and Nutritional Composition of Black Soldier Fly (Hermetia illucens) Larvae and Prepupae Reared on Coconut Endosperm and Soybean Curd Residue with or without Supplementation

“…2 Each diet contains five grams of supplement comprising monodicalcium phosphate, lime stone, DL-methionine, L-lysine, L-threonine, lard, and vitamin-mineral premix (Feed specialties Co., Ltd.; Pathumthani, Thailand) at 2.2 g, 1 g, 0.3 g, 0.14 g, 0.06 g, 1 g, and 0.3 g, respectively. 3 Total larvae and/or prepupae were used to calculate these parameters in each study group. 4 Larval weight gain in fresh matter was calculated between 7-to 14 day-old larvae.…”

“…2 Chicken diet (Starter) contains corn meal, soybean meal, palm oil, monodicalcium phosphate, limestone, salt, vitamin-mineral premix (Feed specialties Co., Ltd.; Pathumthani, Thailand), DL-methionine, sodium bicarbonate, and choline chloride at 50.8%, 39.3%, 6.06%, 1.38%, 1.38%, 0.24%, 0.36%, 0.25%, 0.20%, and 0.07%, respectively. 3 Five grams of supplement contains monodicalcium phosphate, lime stone, DL-methionine, L-lysine, L-threonine, lard, and vitamin-mineral premix (Feed specialties Co., Ltd.; Pathumthani, Thailand) at 2.2 g, 1 g, 0.3 g, 0.14 g, 0.06 g, 1 g, and 0.3 g, respectively.…”

“…One-point-three billion tons of food waste is estimated to be generated per year following the sharp increase of consumption [2]. This large amount of organic waste is mainly sent to the landfill [3]. The gas released from this landfill contributes to the greenhouse effect and global warming [4,5].…”

Microplastics affected black soldier fly (Hermetiaillucens) pupation and short chain fatty acids

“…This could have ecological implications, especially considering adult black soldier flies are pollinators (Srikanth et al, 2013). Moreover, there has been increasing interest in feeding BSFL with landfill residue and leachate as an environmentally friendly method to convert this waste into a high‐value product with good productivity (Grossule & Lavagnolo, 2020; Grossule et al., 2019; Popa and Green, 2012). Indeed, BSFL can thrive on various organic wastes (Beskin et al., 2018; Lalander et al, 2019; Spranghers et al, 2017; Ewald et al, 2020) and have been touted as a novel, sustainable and beneficial ingredient source in various animal feeds (Belghit et al., 2019; Kawasaki et al, 2019; Moula et al, 2018; Secci et al, 2018).…”

Preparation of artificial MSW leachate for treatment studies: Testing on black soldier fly larvae process

“…The best growth performance occurred in the presence of solid support. Grossule et al (2020) investigated larval growth performance using a series of solid supports, some of which providing nutrients and degradable organics (wheat bran, brewers’ spent grain), observing most effective larval growth in the presence of a higher availability of nutrients and organics. In both studies, however, a wide range of variables were found to contribute concomitantly to the results yielded, including quality of solid supports, quality of leachate, larvae density and organic load.…”