Curcumin Encapsulation in Multilayer Oil-in-Water Emulsion: Synthesis Using Ultrasonication and Studies on Stability and Antioxidant and Release Activities

Abstract

Curcumin is a natural polyphenol compound obtained from the turmeric plant, having numerous promising health benefits. To deliver curcumin into the human body, it is necessary to develop an efficient carrier system for its encapsulation such that the physicochemical properties of curcumin can be preserved during storage. In this study, the encapsulation stability, antioxidant activity, and release properties of curcumin encapsulated in the primary emulsion (PE: 0.0022% (w/w) curcumin, 9.99% (w/w) oil, 0.9% (w/w) whey protein isolate, pH 7) and secondary emulsion (SE: 0.00108% (w/w) curcumin, 4.90% (w/w) oil, 0.443% (w/w) WPI, 0.2% (w/w) sodium alginate, pH 5) prepared using ultrasonication were analyzed. It was observed that the formation of a double-layer coating of secondary biopolymer over the primary coated droplet enhanced the encapsulation efficiency and antioxidant activity of the curcumin during storage for 3 weeks. Moreover, the multilayer emulsions were freeze-dried to see the effect of dehydration of emulsion on the stability of multilayer-coated droplets. Fourier transform infrared analysis indicated the presence of all of the constituents, including curcumin, after the freeze drying of the emulsions. Scanning electron microscopy images showed that the microstructure of emulsion droplets was found to be uniformly distributed in the case of SE. The antioxidant activity of curcumin encapsulated in SE was found to be higher during storage, whereas it was significantly reduced in other encapsulated systems like PE, olive oil, and ethanol. In vitro release of curcumin from the multilayer emulsion was carried out under the simulated intestinal conditions of pancreatin enzyme and bile salt. Maximum releases of 71 and 63% were obtained in SE and PE, respectively, within 2 h of digestion. Overall, this study provides useful information on the formation of multilayer emulsion as a carrier system for the better protection and release of curcumin useful for food and pharmaceutical applications.

Application of Advanced Emulsion Technology in the Food Industry: A Review and Critical Evaluation

“…A recent study showed that the multilayer emulsions formed with ovalbumin as the first layer and gum arabic as the second layer had much smaller droplet sizes and better stability than those formed with the opposite arrangement [64]. Other protein-polysaccharide combinations that have been applied to prepare multilayer emulsions include gelatinchitosan [91], whey protein-alginate [92,93], lactoferrin-alginate [59,94,95], and soy βconglycinin-pectin [96]. Multilayer emulsions can also be stabilized using two or more polysaccharides, one that acts as an emulsifier and the others that form additional layers.…”

Construction, stability and photodynamic germicidal efficacy of curcumin nanoemulsion stabilised with Maillard conjugate of Wpi‐Rha

“…The free radical scavenging rate of Cur‐Ne was shown in Figure 6(a). The DPPH and ABTS free radical scavenging rates of Cur‐Ne at the concentration of 300 μmol/L were 83.52 ± 3.02% and 99.63 ± 0.48%, respectively, which were higher than that of the curcumin nanoemulsion prepared by Saharan (Carpenter et al., 2019). The high antioxidant activity of Cur‐Ne was due to the joint action of curcumin and oregano essential oil.…”

Novel Curcumin-Encapsulated α-Tocopherol Nanoemulsion System and Its Potential Application for Wound Healing in Diabetic Animals

“…The antioxidant activity of curcumin is attributed to its unique conjugated structure, which shows typical radical-trapping ability as a chain-breaking antioxidant [ 55 ]. Numerous studies reported enhanced antioxidant properties of the curcumin encapsulated in colloidal system such as liposomes [ 56 ], polymeric microparticles [ 57 ], hydrogel beads [ 58 ], nanoparticles [ 59 ], and microemulsions [ 60 ]. Curcumin containing microemulsion and microemulsion gel was developed with grape seed oil as a lipid phase, where the synergistic antioxidant activity of the optimized microemulsion and gel microemulsions was observed due to the presence of grape seed oil which helped effectively encapsulate and preserve the antioxidant stability of curcumin [ 61 ].…”