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Bactericidal/permeability-increasing fold containing family A, member 1 (BPIFA1) is an innate immunity defense protein. Our previous studies proved its antibacterial and antiviral effects, but its role in fungi remains unknown. The study aimed to identify antifungal peptides (AFP) derived from BPIFA1, and three antimicrobial peptides (AMP1-3) were designed. The antifungal effects were proved by growth inhibition assay. AMP3 activity was confirmed by germ tube growth experiment and XTT assay. Its effects on cell wall and membrane of Candida albicans were assessed by tannic acid and Annexin V-FITC/PI double staining, respectively. Additionally, scanning electron microscope (SEM) and transmission electron microscopy (TEM) were used for morphological and ultrastructural observation. The expression of ALS1, EAP1, and SUN41 was tested by qPCR. Ultimately, three AMPs could fight against C. albicans in vitro , and AMP3 was highly effective. It functioned by destroying the integrity of cell wall and normal structure of cell membrane. It also inhibited biofilm formation of C. albicans . In addition, AMP3 down-regulated the expression of ALS1, EAP1, and SUN41, those are known to be involved in virulence of C. albicans . Altogether, the study reported successful development of a novel AFP, which could be used as a new strategy for antifungal therapy.

The present study deals with novel synthesizing method of TEMPO oxidized cellulose (extracted from bagasse) (TOC) amino acids (l-phenyl alanine (Phe) and l-tryptophan (Trp)) nano-composites as potential antimicrobial biocompatible agents. The produced nanocomposites were characterized via Fourier transform Infrared (FT-IR) spectroscopy, thermal analysis (TGA and DTGA), scanning electron microscope(SEM), and transmission electron microscope (TEM) which approved that the synthesis of composites in nano-scale in spherical shape with average particle size 72 and 44.37 nm for l-phenylalanine composite (Phe-TOC) and l-tryptophan composite (Trp-TOC) respectively. The antimicrobial studies were carried out on (i) Gram-negative bacteria: Escherichia coli (NCTC-10416) and Pseudomonas aeruginosa (NCID-9016); (ii) Gram-positive bacteria: Streptococcus aurous (NCTC-7447) and Bacillus subtilis (NCID-3610); (iii) unicellular fungi: namely, Candida albicans (NCCLS 11). The results were cleared that the both composites have high effective, rapid and broad-spectrum antimicrobial activity. The Trp-TOC showed slightly higher antimicrobial activity than Phe-TOC especially in time required of killing performance. The Phe-TOC has required 20 h for killing all microbial population while Trp-TOC required only 12 h. The MIC values were close in both nanocomposites with high clear zone measurements in the same concentration in the case of Trp-TOC., (Copyright © 2019 Elsevier B.V. All rights reserved.)