Antimicrobial peptides from the edible insect Musca domestica and their preservation effect on chilled pork

Abstract

Antimicrobial compounds from natural sources are a promising alternative to address the consumer demand of food without chemical additives. In this study, antimicrobial peptides (AMPs) from infected Musca domestica pupae (Md‐AMPs) bred under clean conditions were isolated and prepared on a large scale. In these Md‐AMPs, seven AMPs families were identified by liquid chromatography–tandem mass spectrometry. Md‐AMPs at concentrations from 0.4 to 0.8 mg/ml exhibited antibacterial activity and showed negligible hemolytic activity against human erythrocytes. Md‐AMPs increased bacterial membrane permeability of four tested strains, resulting in the leakage of phosphorus‐containing materials and Ca2+. Md‐AMPs bound plasmid DNA and inhibited its migration in a concentration‐dependent manner. Treatment with Md‐AMPs alone or in combination with nisin, and ethylenediaminetetraacetic acid was efficient in inhibiting bacterial growth in chilled pork and extended the shelf life up to 6 days. Practical applications Insects have been widely used as foods and many biofunctional components are found in insects. In this work, we isolated and prepared AMPs from M. domestica, and its antibacterial activity, hemolytic activity, and mechanism of action were investigated. Trials in real food products showed that Md‐AMPs alone or a combination of three natural antimicrobials could remarkably inhibit bacterial growth in chilled pork. These results suggest that Md‐AMPs can be used as food preservatives.

Suppression of Transferrin Expression Enhances the Susceptibility of Plutella xylostella to Isaria cicadae

“…Naïve larvae and I. cicadae (1.0 × 10 7 cfu/larvae)-challenged larvae (24 h) were homogenized with precooled phosphate buffer saline (PBS) and centrifuged at 10,000× g for 30 min at 4 • C. The supernatants were used for protein identification. PxTrf protein was identified through liquid chromatography-tandem mass spectrometry (LC-MS/MS) according to a previously described method [26]. On the basis of combined MS and MS/MS spectra, protein was successfully identified on the basis of a 95% or higher confidence interval of their scores in the MASCOT V2.3 search engine (Matrix Science Ltd., United Kingdom).…”

Multiobjective optimization ofPhoenix dactyliferaL. seeds extraction: Mixture design methodology for phytochemical contents and antibacterial activity

“…Foodborne pathogens are the main factors behind foodborne diseases and food poisoning and thus pose a great threat to food safety (Dang et al., 2020; Thum et al, 2019; Zhao, Zhao, Wang, & Zhong, 2017). There are many kinds of foodborne pathogens, such as Listeria monocytogenes , Staphylococcus aureus, and Salmonella , which commonly contaminate fruits, vegetables, meat, and seafood, (Liaqat, Zahoor, Atif Randhawa, & Shahid, 2019; Boukhris et al, 2020).…”

Silencing β‐1,3‐glucan binding protein enhances the susceptibility of Plutella xylostella to entomopathogenic fungus Isaria cicadae

“…The I. cicadae (1.0 × 10 7 CFU larvae −1 ) challenged larvae (24 h) and naïve larvae were homogenized and centrifuged at 10 000 × g for 30 min at 4 °C. The supernatant was used for the protein identification by liquid chromatography–tandem mass spectrometry (LC–MS/MS) according to a previously described method 24 . The absolute quantification of PxβGBP was estimated by the exponentially modified protein abundance index (emPAI) method 25 .…”

“…The supernatant was used for the protein identification by liquid chromatography-tandem mass spectrometry (LC-MS/MS) according to a previously described method. 24 The absolute quantification of Px⊎GBP was estimated by the exponentially modified protein abundance index (emPAI) method. 25 All tests were repeated three times.…”