Author/Authors :
Cheraghali, Fatemeh Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Shojaee-aliabadi, Saeedeh Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Hosseini, Marzieh Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Mirmoghtadaie, Leila Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Mortazavian, Amir Mohammad Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Ghanati, Kiandokht Department of Research - International Shahid Beheshti University of Medical Sciences, Iran , Abedi, Abdol-Samad Department of Food Science and Technology - National Nutrition and Food Technology Research Institute - Faculty of Nutrition Sciences and Food Technology - Shahid Beheshti University of Medical Sciences, Iran , Moslemi, Masumeh Food and Drug Control Reference Laboratories Center - Food and Drug Organization - Ministry of Health and Medical Education, Tehran, Iran
Abstract :
Background: Walnut green husk (WGH) extract has been known as potential preventive and
therapeutic antioxidants and antimicrobials due to its high polyphenol content. In this study,
preparation of spray dried WGH extract‑loaded microcapsules by maltodextrin and its blending
with two other natural biodegradable polymers, pectin, or alginate were investigated. Methods: In
this study, encapsulation efficiency (EE), total phenol content (Folin–Ciocalteu reagent method),
antioxidant (DPPH scavenging assay) and antimicrobial activities (agar well diffusion method)
structural (SEM and FTIR studies), and release properties of WGH extract‑loaded microcapsules
were investigated. Results: High retention of phenolic content in microcapsules indicated the
successful encapsulation of WGH extract. Addition of biopolymers to maltodextrin matrix has
a positive effect on EE and other properties of microcapsules. The microcapsules prepared
with mixture of maltodextrin and pectin had higher EE (79.35 ± 0.87%) and total phenolic (TP)
content (56.83 ± 1.04 mg gallic acid equivalents [GAE]/100 g) in comparison to maltodextrin and
alginate mixture (EE: 75.21 ± 0.24%, TP content: 54.33 ± 1.53 mg GAE/100 g) and maltodextrin
only matrix (EE: 72.50 ± 1.00%, TP content: 50.67 ± 1.35 mg GAE/100 g). Extract‑loaded
microcapsules also showed nearly spherical structure, good antioxidant (with the percentage DPPH
inhibition ranged from 75.17 ± 1.42% to 80.87 ± 2.29%), and antimicrobial properties (with mean
inhibition diameter zone ranged from 7.76 ± 0.86 mm to 11.53 ± 0.45 mm). Fourier transform
infrared analyses suggested the presence of extract on microcapsules. The in vitro extract release
from microcapsules followed an anomalous non‑Fickian diffusion mechanism with almost complete
release. Conclusions: WGH extract microcapsules can be used as novel and economic bioactive
phytochemical and therapeutic agents to prevent oxidation and microbial activity.
Keywords :
Antioxidants , Juglans , microencapsulation , polyphenols
