Effect of Microencapsulation on Antimicrobial and Antioxidant Activity of Nutmeg Oleoresin Using Mixtures of Gum Arabic, OSA, and Native Sorghum Starch

• Published in: Starch - Stärke 2018-07, Vol.70 (7-8), p.n/a
• Main Authors: Arshad, Hira, Ali, Tahira Mohsin, Abbas, Tanveer, Hasnain, Abid
• Format: Article
• Language: English
• Subjects: Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; Antioxidants; Biological activity; Drying; E coli; Flavonoids; Fourier transforms; Gums; Inflammation; Microcapsules; Microencapsulation; Nutmeg; nutmeg oleoresin; Organic chemistry; Phenolic compounds; Phenols; Scanning electron microscopy; Sorghum; sorghum starch; Spray drying; Starch
• ISSN: 0038-9056; 1521-379X
• DOI: 10.1002/star.201700320

Nutmeg (Myristica fragrans Houtt) and its solvent extracts are being used across the world for their strong anti‐inflammatory, antioxidant and antimicrobial activity attributed to their naturally occurring phytochemicals. The loading of nutmeg oleoresin in a matrix of gum arabic and sorghum starch (native and OSA modified) in different ratios is achieved in this study through microencapsulation by using a spray drying method. Morphological and chemical changes after modification of starch are analyzed through scanning electron microscopy and FTIR spectroscopy, respectively. Both native and modified sorghum starch granules are found to be polygonal and spherical in shape. The bioactive extracts from the microcapsules are analyzed for DPPH radical scavenging activity, phenolic content, flavonoid content, and antimicrobial activity. Extracts from the nutmeg microcapsules comprised of gum arabic and OSA modified sorghum starch possess excellent bioactive functional properties as compared to native sorghum starch. The samples comprised of gum arabic and starch (native and OSA modified) in the ratio of (75:25) and (50:50) show excellent antioxidant activity and high retention of phenolic and flavonoid content after 60 days of storage. All the bioactive extracts show antimicrobial activity against Escherichia coli and Bacillus cereus. Nutmeg oleoresin has strong anti‐inflammatory, antioxidant and anti‐microbial activity due to the presence of natural phytochemicals. Microencapsulation through spray drying is a widely used technique to envelop these phytochemicals within polymer coating of micron size. Gum arabic, sorghum and OSA sorghum were used to encapsulate nutmeg oleoresin by spray drying. The extract of these microcapsules has excellent antioxidant and antimicrobial properties.