Antibacterial Activity of Combined Nanodiamonds and Snail Fractions with Biocompounds with MW below 10 kDa and above 30 kDa

Abstract

The use of nanomaterials for enhancement of the antibacterial activity of different compounds is a new approach contributing to the efforts of overcoming the emerging antibiotics resistance. This study explores the combined antibacterial activity of nanodiamonds and snail peptides against Brevibacillus laterosporus BT271. Two peptide/protein fractions from Cornu aspersum mucus were used – with molecular weight (MW) below 10 kDa and with MW above 30 kDa. Four types of nanodiamonds (ND) were tested (positively charged, single digit and two types of detonation ND). Peptide fractions were characterized by using MALDI-TOF. The fraction with MW below 10 kDa consisted of many different peptides, while the fraction with proteins above 30 kDa showed proteins at m/z 26879.2 Da, 33903.11 Da, 43583.81 Da, 53986.81 Da, 79091.82 Da, 100650.42 Da, and 141 550.82 Da. When mixture peptides+ND was applied directly on the bacterial culture, the nanodiamonds showed enhanced antibacterial effect from 8% up to 42%. The combination of nanodiamonds and the mucus fraction with MW above 30 kDa had strongest bactericidal effect (1593.04 mm2/mgP*μL). The results demonstrated that ND have potential to enhance the antibacterial activity of the snail peptides but also highlighted that their effects should be carefully studied.