Alginate Microbeads for Trapping Phenolic Antioxidants in Rosemary (Rosmarinus officinalis L.): Multivariate Optimization Based on Bioactive Properties and Morphological Measurements


Toprakçı G., Toprakçı Yüksel İ., Şahin Sevgili S.

GELS, cilt.11, sa.3, ss.172-194, 2025 (SCI-Expanded, Scopus) identifier identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 11 Sayı: 3
  • Basım Tarihi: 2025
  • Doi Numarası: 10.3390/gels11030172
  • Dergi Adı: GELS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Directory of Open Access Journals
  • Sayfa Sayıları: ss.172-194
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Evet

Özet

Medical and aromatic plant extracts are often very sensitive to environmental, gastrointestinal, and processing conditions despite their health benefits. Therefore, they can be rapidly inactivated. Microencapsulation is used to overcome such challenges. In this study, phenolic antioxidants from rosemary (Rosmarinus officinalis L.) were encapsulated in alginate beads by means of ionic gelation. A Box–Behnken design with response surface methodology (BBD–RSM) was used with three numeric factors (calcium chloride concentration, alginate concentration, and hardening time) to achieve the best formulation in terms of encapsulation efficiency, antioxidant activity, and morphological characteristics. Generally, the sodium alginate concentration of the microbeads was the most critical factor (p < 0.0001) for the quality of the products. The optimal encapsulation conditions were accessed using concentrations with almost 6% calcium chloride and 2% alginate, and a time of 10 min for bead hardening in order to obtain the highest responses (30.01% encapsulation efficiency, 7.55 mg-TEAC/g-DM of antioxidant activity value as measured by the DPPH method, a sphericity factor of 0.05, and a roundness of 0.78). At the optimum point, the microbeads were determined to be spherical in shape, and the bulk density value was measured as 0.34 ± 0.01 g/mL.