Chitosan-based active films were developed by incorporation of carvacrol (10 g/L), pomegranate peel extract (PPE, 10 g/L) and carvacrol + PPE (10 g/L of each) and their physical, antioxidant and antimicrobial properties were investigated. Incorporation of carvacrol and carvacrol + PPE into the films significantly decreased the water vapor permeability, tensile strength and percentage of elongation at break. Incorporation of carvacrol, PPE and carvacrol + PPE into the films decreased the transparency, but significantly increased the total phenol content and antioxidant activity. All the films, with the exception of PPE-incorporated film, exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, the antibacterial activity against Staphylococcus aureus of the film incorporated with carvacrol + PPE was moderately higher than that incorporated with carvacrol or PPE alone, suggesting a synergistic action between carvacrol and PPE.

PUA could ameliorate obesity and liver steatosis in mice induced by HFD via regulating the gut microbiota composition.

A novel analytical method for rapid determination of histamine in fish involves methanol extraction, manual spotting, thin-layer chromatography (TLC) for less than 15 min, visualization by diazotized p-nitroaniline reagent, and quantitation by image analysis using the ImageJ software. Following this procedure, histamine can be successfully detected and completely separated from other biogenic amines and diazonium reagent's positive compounds. Moreover, this method does not require any expensive reagent and instrument as well as any tedious sample pre-treatment. The characterization of this method revealed good specificity, linearity in the range of 100–1200 ng per spot (adjusted R-square = 0.9987), precision (relative standard deviation, 1.07–2.76%), accuracy (with a trueness of 1.76–6.22%), recovery rate (93.78–98.24%), limit of detection (23.49 ng per spot), and limit of quantitation (78.29 ng per spot). The proposed method is simpler, faster and less expensive than HPLC and the previously reported TLC/HPTLC. Therefore, this method has the potential to be adapted by aquatic enterprises and aquatic market supervision commissions for monitoring the quality of seafood products during processing, storage, and sales.

Squid ink melanin can be efficiently extracted from the byproduct ink sac generated during squid processing. As a natural food colorant, it possesses inherent antioxidant properties and the capability to adsorb heavy metals. This study aims to investigate the solubility of water-soluble squid ink melanin (WSSM) obtained from the ink sac, as well as its stability under various conditions including temperature, pH, salt, sugar, potassium sorbate, metal ions, sodium benzoate, sodium sulfite (reducing agent), and hydrogen peroxide (oxidizing agent). Moreover, it explores the scavenging effects of WSSM on free radicals and cadmium ions. The findings suggest that WSSM’s stability is insignificantly affected by high temperature, sucrose, and salt. However, acidity, sodium benzoate, potassium sorbate, sodium sulfite (Na₂SO₃), and hydrogen peroxide (H₂O₂) significantly influence its stability. Most metal ions do not impact the stability of WSSM, except for Fe²⁺, Fe³⁺, Al³⁺, and Cu²⁺, which result in the precipitation of WSSM. Additionally, WSSM exhibits remarkable antioxidant activity with IC₅₀ values of 0.91, 0.56, and 0.52 mg/mL for scavenging superoxide anion radicals (O²⁻·), hydroxyl radicals (·OH), and DPPH radicals, respectively. It also demonstrates the ability to adsorb the heavy metal Cd²⁺, with the adsorption rate gradually increasing with a higher temperature and larger amounts of WSSM added. Infrared spectroscopy analysis reveals the weakening of characteristic peaks (-COOH and -OH) during the process of Cd²⁺ adsorption by WSSM, while SEM confirms surface roughening and structural damage after Cd²⁺ adsorption. This study provides valuable insights for the utilization of squid melanin products as natural antioxidants and heavy metal adsorbents in the food industry.