Antimicrobial Effect of Zophobas morio Hemolymph against Bovine Mastitis Pathogens

Abstract

Coliforms and Staphylococcus spp. infections are the leading causes of bovine mastitis. Despite extensive research and development in antibiotics, they have remained inadequately effective in treating bovine mastitis induced by multiple pathogen infection. In the present study, we showed the protective effect of Zophobas morio (Z. morio) hemolymph on bovine mammary epithelial cells against bacterial infection. Z. morio hemolymph directly kills both Gram-positive and Gram-negative bacteria through membrane permeation and prevents the adhesion of E. coli or the clinically isolated S. simulans strain to bovine mammary epithelial (MAC-T) cells. In addition, Z. morio hemolymph downregulates the expression of nucleotide-binding oligomerization domain (NOD)-like receptor family member pyrin domain-containing protein 3 (NLRP3), caspase-1, and NLRP6, as well as inhibits the secretion of interleukin-1β (IL-1β) and IL-18, which attenuates E. coli or S. simulans-induced pyroptosis. Overall, our results suggest the potential role of Z. morio hemolymph as a novel therapeutic candidate for bovine mastitis.

Therapeutic Effect of Darkling Beetle (Zophobas morio) Hemolymph on Skin Thermal Injury in Mice Infected by Staphylococcus haemolyticus

“…The wound area temperature of hemolymph antibacterial protein treatment group was closer to the control group, which suggests that hemolymph can relieve symptoms of elevated local wound temperature. Z. morio hemolymph showed excellent antibacterial activity in vitro, and had a superior bactericidal effect on S. aureus ATCC25923 [17]. Our study showed that the Z. morio hemolymph can significantly reduce the load of S. haemolyticus in the wound tissue of mice, which may be related to a previous report, in which Z. morio hemolymph can increase the permeability of the bacterial membrane, destroy cell membrane integrity and kill the bacteria [17].…”

“…In our previous study, a natural hemolymph antimicrobial extract from Z. morio had a positive antibacterial effect, which can maintain antibacterial ability after various physical and chemical treatments [17]. At the same time, it does not have hemolysis ability and obvious cytotoxicity at an effective bactericidal concentration range [17].…”

“…Erythromycin ointment was purchased from Mayinglong Pharmaceutical Group Co., Ltd., Dingzhou, Baoding, China. The extraction and preparation of the antibacterial hemolymph of Z. morio were carried out according to the preliminary research results of our laboratory [17].…”

“…Our previous study showed that the antibacterial protein extracted from the darkling beetle (Zophobas morio) had a high safety, stability, and antibacterial effect on the pathogen of bovine mastitis, including S. aureus. An in vitro study proved that the Z. morio hemolymph can reduce the expression of pro-inflammatory factors, including interleukin-1β (IL-1β) and interleukin-18 (IL-18) [17], which suggests that Z. morio hemolymph can be used as a novel therapeutic drug to reduce pathogen infection in animals. Nevertheless, we hypothesize that Z. morio hemolymph in vivo to treat S. haemolyticus infection, remains largely understudied.…”

The Superworm, Zophobas morio (Coleoptera:Tenebrionidae): A ‘Sleeping Giant’ in Nutrient Sources

“…The spectrum of Z. morio applications is continuously growing. Recently, Du et al (2020) showed that Z. morio hemolymph can effectively protect bovine mammary epithelial cells against bacterial infections and proposed Z. morio hemolymph as an efficient, alternative therapeutic candidate for bovine mastitis, the most prevalent disease affecting the dairy industry worldwide. Additionally, this species is often used as a model organism.…”