Postharvest preservation of apples and potatoes using a Dictyosphaerium algal oil emulsion–chitosan hydrogel coating: efficacy against Enterobacter mori.


Faheem S., Ullah S., Maryam S., Bhatti M. F., Yousaf K., Arshad M., ...Daha Fazla

Materials Today Communications, cilt.52, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 52
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.mtcomm.2026.115051
  • Dergi Adı: Materials Today Communications
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, INSPEC
  • Anahtar Kelimeler: Algal emulsions, Post-harvest losses, Shelf-life enhancement
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Microbial spoilage after harvest is a major cause of loss of perishable crops, and therefore preservation methods that are cost-effective and efficient are required, especially in resources limited situations. Here, algal oil extracted from Dictyosphaerium sp. (DHSYM) was formulated as an oil-in-water emulsion and incorporated into a chitosan hydrogel coating to inhibit Enterobacter mori and extend the shelf life of apples and potatoes. The resultant emulsion showed a Z-average droplet size of 831.3 nm and a polydispersity index value (PDI) of 0.341 and thus had a relatively small droplet size distribution. In agar diffusion assays, the emulsion produced inhibition zones of 9–17 mm (5–15 mg/mL), while emulsion-loaded chitosan hydrogel increased inhibition to 11–19 mm compared with hydrogel alone (∼7 mm) [control: cefotaxime 20 mm]. The coating exhibited a hydrophilic property reaching 39° contact angle and cell viability of 80–85% in HEK-293 cells across tested concentrations, suggesting low cytotoxicity. When applied as a dip-coating, the hydrogel increased apple shelf life by ∼1 week and preserved potatoes for ' 1 month under the tested storage conditions. Structural and functional characterizations were conducted to assess the properties of the hydrogel, including SEM, FTIR, RAMAN, GC-MS, compression analysis, thermal gravimetric analysis, contact angle measurement, biofilm eradication, antibacterial activity, MTT assay, molecular docking, and toxicity profiling. GC-MS detected several compounds; selected ligands (D -limonene, oxalic acid diallyl ester, piperazine, 1,3 bis dimethylethyl and carbonic acid) were prioritized for docking based on reported antimicrobial relevance. These findings prove algal emulsion-chitosan hydrogels as a promising bio-based coating; however, validation with larger sample sizes, defined storage conditions, and statistical comparisons are required.