Antifungal efficacy of kenaf seed peptides mixture in cheese, safety assessment and unravelling its action mechanism against food spoilage fungi

This study investigated the preservation efficacy of kenaf seed peptides mixture(KSPM)in extending the shelf-life of cream cheese matrix and the effect on its physicochemical properties.Also,the safety of KSPM towards mammalian cells and the underlying fungicidal mode of action in-vitro and in-silico were assessed.The KSPM at 500 and 1000 mg/kg effectively prolonged the shelf-life of cream cheese for up to 11-21 days when stored at 25℃ and 4℃,and significantly reduced the inoculated conidia counts by~3 log_(10) conidia/g.The safety assessment showed that KSPM maintained the proliferation of normal cell lines up to 30 mg/mL.The cell surface potential energy and hydrophobicity of fungi were altered due to the potent interactions between the peptides and the cell envelope,with KSPM causing significant fungal cell wall permeability and subsequent disruption of the cytoplasmic membrane integrity.KSPM treatment induced morphological destruction of conidia and mycelium and caused a significant loss of fungal cellular materials including K^(+),sugar,protein and nucleic acids(DNA and RNA),indicating irreversible damage to the fungal cytoplasmic membrane.The in-silico molecular docking study revealed that the peptides mixture efficiently interacted with fungal mannoprotein via the formation of hydrogen bonding,electrostatic interactions and hydrophobic forces.The molecular dynamics simulation showed that the peptide KPTGMR was tightly embedded into the fungal phospholipid bilayer membrane and inserted into the phosphate head groups which led to the formation of gaps,suggesting a transmembrane pore or channel action mechanism.

Enzymolysis of Azolla pinnata protein concentrate:Effect of protease types and hydrolysis extents on the physicochemical,techno-functional and biological properties

Azolla pinnata is an underutilised fern and has been found to be a highly promising and sustainable source,making it a potential new plant-based protein source that can be used as a functional food ingredient.Therefore,the present work produced Azolla pinnata fern protein concentrate(AFPC)through alkaline solubilisation with isoelectric precipitation and investigated the effect of different proteases at varying degree of hydrolysis(DH)on the physicochemical,techno-functional properties and biological activities of Azolla fern protein hydrolysates.Enzymolysis with all proteases decreased the hydrophobicity,denaturation temperature and secondary struc-tures(β-sheet andα-helix)as the DH increased.Furthermore,the techno-functional properties including water and oil holding capacities,emulsion properties and foam stability were significantly reduced with increasing the DH,except for solubility and foaming capacity.Additionally,the pH had a positive correlation with all the techno-functional properties,except for water holding capacity.Hydrolysis with all proteases had a positive effect on the antioxidant and antibacterial activities.The partially hydrolysed protein with alcalase showed excellent techno-functional and antioxidant properties,while excellent antibacterial activity was observed for hydrolysate produced by flavourzyme under extensive hydrolysis.The current findings pave the way for the application of Azolla fern protein hydrolysates as promising and sustainable plant-based peptide to be utilised as nutraceutical and functional food ingredients.

Corrigendum to“Enzymolysis of Azolla pinnata protein concentrate:Effect of protease types and hydrolysis extents on the physicochemical,techno-functional and biological properties”[Food Bioscience 53(June 2023)102787]

The authors regret for the typo error made in the materials and methods section under the subtopic 2.2.2.and 2.2.3 in the original article.Subtopic 2.2.2 In the original article:“The AFPC powder was individually homo-genised in a specific buffer to yield a 1%(w/v)solution and hydrolysed using different enzymes at 3%(w/v)including trypsin….”