Antimicrobial effect of bayberry leaf extract for the preservation of large yellow croaker (Pseudosciaena crocea).
BACKGROUND
Chemical preservatives have been widely used to keep large yellow croaker fresh. However, the potential harm to human health cannot be ignored. This study was undertaken to investigate the antimicrobial effect of bayberry leaf extract and to evaluate the efficacy of this natural product on the preservation of large yellow croaker.


RESULTS
The minimum inhibitory concentration (MIC) values of bayberry leaf extract against bacteria were 1.0 mg mL⁻¹ for Micrococcus luteus, 0.5 mg mL⁻¹ for Staphylococcus aureus, 0.25 mg mL⁻¹ for Escherichia coli, 0.5 mg mL⁻¹ for Pseudomonas aeruginosa, 0.0625 mg mL⁻¹ for Vibrio parahaemolyticus, and 0.03125 mg mL⁻¹ for Listeria monocytogenes, respectively. This result was confirmed by the diameters of inhibition zone (DIZ) assay. Further studies showed that the bacterial growth was significantly retarded when large yellow croaker was pretreated with bayberry leaf extract (2 g L⁻¹) compared to that in the control group. Moreover, the generation of total volatile basic nitrogenous compounds (TVB-N), ATP degradation products (K-value) and thiobarbituric acid-reactive substances (TBARS) were significantly reduced compared to that in the control group.


CONCLUSIONS
Our results demonstrated that the shelf life of large yellow croaker can be extended when supplemented with bayberry leaf extract, which might have implications for natural preservatives.
College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310035, China.
Hongming
H
Su
Wei
W
Chen
Shalu
S
Fu
Chu
C
Wu
Kai
K
Li
Zhaoyi
Z
Huang
Tao
T
Wu
Jianrong
J
Li
D000818:Animals; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000737:chemistry / Q000302:isolation & purification*; D002681:China; D005520:Food Preservatives / Q000009:adverse effects / Q000737:chemistry / Q000302:isolation & purification*; D063427:Food Quality; D061353:Food Storage; D005517:Foodborne Diseases / Q000382:microbiology / Q000517:prevention & control; D006090:Gram-Negative Bacteria / Q000254:growth & development / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000254:growth & development / Q000302:isolation & purification; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015227:Lipid Peroxidation; D008826:Microbial Sensitivity Tests; D031641:Myrica / Q000737:chemistry*; D010140:Pacific Ocean; D010473:Perciformes / Q000382:microbiology*; D010936:Plant Extracts / Q000009:adverse effects / Q000737:chemistry / Q000302:isolation & purification*; D018515:Plant Leaves / Q000737:chemistry*; D059748:Proteolysis; D017747:Seafood / Q000032:analysis / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D005520:Food Preservatives; D010936:Plant Extracts
Pseudosciaena crocea; antimicrobial; bayberry leaf extract; natural preservatives