Fatty Acids-Enriched Fractions of <i>Hermetia illucens</i> (Black Soldier Fly) Larvae Fat Can Combat MDR Pathogenic Fish Bacteria <i>Aeromonas</i> spp.
<i>Aeromonas</i> spp. cause many diseases in aquaculture habitats. <i>Hermetia illucens</i> (Hi) larvae were used as feed-in aquacultures and in eradicating pathogenic fish bacteria. In the present study, we applied consecutive extractions of the same biomass of BSFL fat usin...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-08-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/22/16/8829 |
| Summary: | <i>Aeromonas</i> spp. cause many diseases in aquaculture habitats. <i>Hermetia illucens</i> (Hi) larvae were used as feed-in aquacultures and in eradicating pathogenic fish bacteria. In the present study, we applied consecutive extractions of the same biomass of BSFL fat using the acidic water–methanol solution. The major constituents of the sequential extracts (SEs) were free fatty acids (FFAs), and fatty acids derivatives as identified by gas chromatography spectrometry (GC-MS). Our improved procedure enabled gradual enrichment in the unsaturated fatty acids (USFAs) content in our SEs. The present study aimed to compare the composition and antimicrobial properties of SEs. Among actual fish pathogens, <i>A. hydrophila</i> and <i>A. salmonicida</i> demonstrated multiple drug resistance (MDR) against different recommended standard antibiotics: <i>A. salmonicida</i> was resistant to six, while <i>A. hydrophila</i> was resistant to four antibiotics from ten used in the present study. For the first time, we demonstrated the high dose-dependent antibacterial activity of each SE against <i>Aeromonas</i> spp., especially MDR <i>A. salmonicida</i>. The bacteriostatic and bactericidal (MIC/MBC) activity of SEs was significantly enhanced through the sequential extractions. The third sequential extract (AWME3) possessed the highest activity against <i>Aeromonas</i> spp.: inhibition zone diameters were in the range (21.47 ± 0.14–20.83 ± 0.22 mm) at a concentration of 40 mg/mL, MIC values ranged between 0.09 and 0.38 mg/mL for <i>A. hydrophila</i> and <i>A. salmonicida</i>, respectively. AWME3 MBC values recorded 0.19 and 0.38 mg/mL, while MIC<sub>50</sub> values were 0.065 ± 0.004 and 0.22 ± 0.005 mg/mL against <i>A. hydrophila</i> and <i>A. salmonicida</i>, respectively. Thus, the larvae fat from <i>Hermitia illucens</i> may serve as an excellent reservoir of bioactive molecules with good capacity to eradicate the multidrug-resistant bacteria, having promising potential for practical application in the aquaculture field. |
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| ISSN: | 1661-6596 1422-0067 |