An Overview of Antimicrobial Compounds from African Edible Insects and Their Associated Microbiota

Abstract

The need for easily biodegradable and less toxic chemicals in drug development and pest control continues to fuel the exploration and discovery of new natural molecules. Like certain plants, some insects can also respond rapidly to microbial infections by producing a plethora of immune-induced molecules that include antibacterial and antifungal peptides/polypeptides (AMPs), among other structurally diverse small molecules. The recent recognition that new natural product-derived scaffolds are urgently needed to tackle life-threatening pathogenic infections has been prompted by the health threats posed by multidrug resistance. Although many researchers have concentrated on the discovery of AMPs, surprisingly, edible insect-produced AMPs/small molecules have received little attention. This review will discuss the recent advances in the identification and bioactivity analysis of insect AMPs, with a focus on small molecules associated with the microbiota of selected African edible insects. These molecules could be used as templates for developing next-generation drugs to combat multidrug-resistant pathogens.

Biological activity of extracts and hydrolysates from early- and adult-stage edible grasshopper Sphenarium purpurascens

“…For example, in a previous study, housefly larvae were inoculated with a suspension of Salmonella pullorum cells to obtain AMP ( 19 ). Another example is a study where crickets were infected with Photorhabdus asymbiotica and derived from the infection, and glidobactin A, luminmycin, and luminmycin D were isolated ( 32 ). Considering that the crickets and grasshoppers belong to the Orthoptera order, it could be possible to obtain antimicrobial compounds stimulating their production.…”

Antibiotics from Insect-Associated Actinobacteria

“…Despite it not being focused on a specific genus and type of compounds, we could recognize it as a starting point for our literature selection: the current review is covering January 2016–August 2022. From the latest years we should highlight some works on specific types of insects or ecological niches: fungus-growing ants [ 29 ], African edible insects [ 30 ], neotropical insects [ 31 ] and fungus-farming termites [ 32 ]. A critical review on microbial symbionts of insects as a source of new antimicrobials from our Belgian colleagues [ 18 ] is the most relevant and closest to our work, but it does not have a systematic character and is not focused on actinomycetes as a major source of antimicrobials.…”

Waste to value: Global perspective on the impact of entomocomposting on environmental health, greenhouse gas mitigation and soil bioremediation

“…, E. coli , Clostridium perfringens , Listeria monocytogenes and Enterococcus ) ( Liu et al, 2017 ; Brochier et al, 2012 ) that may not be reduced to permissible levels by conventional composting methods ( Brinton, 2000 ). The BSF larval gut has antimicrobial peptides such as StomoxynZH1 and DLP4 ( Mudalungu et al, 2021 ; Vogel et al, 2018 ) that have potential to suppress several microbial pathogens that usually persist in compost ( Vogel et al, 2018 ; Elhag et al, 2017 ; Yi et al, 2014 ). The other mechanisms of pathogen suppression include microbe ingestion and/or lysis inside the insect gut ( Tanga et al, 2021b ).…”