The bioactive compounds in extracts are prone to degradation by oxidation, heat, or light. Nanoencapsulation is one of the best techniques to keep the properties of these chemical compounds. The aim of this study was the extraction of Melissa officinalis (MO) and Nanoencapsulation of the extract via chitosan as a biodegradable polymer. In this research, extraction of MO was investigated using various extraction methods and Nanoencapsulation with MO extract was carried out via ionic gelation technique. The effectiveness of the extracts was evaluated by measuring the total phenolic content (TPC), antioxidant activity, and extraction efficiency of the solid contents. The highest efficiency was achieved for microwave-assisted extraction with the utmost values in each parameter. (TSC) was 22.81% and amounts of the TPC and antioxidant activity were 311.94 mg Gallic acid and 36 mg diphenyl picryl hydrazyl (DPPH) per 1g of the plant, respectively.  Morphology study by field emission scanning electron microscopy (FE-SEM) indicated spherical shape nanoparticles with a diameter of 25nm. The size of the nanoparticles was evaluated by the Dynamic Light Scattering (DLS) technique for various concentrations of the used extracts in the encapsulation process. For 1.0, 3.0, and 5.0 mg /mL concentration, mean diameters were 24, 118, and 145 nm, respectively. Results indicated that microwave-assisted extraction was the best extraction method for MO and the encapsulation of MO extract could be created successfully with different particle sizes for the protection of bioactive compounds. Since MO is a beneficial herbal plant, the development of this research is recommended.

Cream cheese is a valuable dairy product rich in calcium but highly perishable. Gingerol exhibits multiple functional properties, including antioxidant and antimicrobial activities; however, its pungent taste and thermal instability limit its application in food products. To overcome these limitations, we encapsulated gingerol with WPI and incorporated it into cream cheese. Gingerol was coated at concentrations of 0.5%, 1% and 2% with different WPI concentrations of 5%, 10%, and 15%. Encapsulation Efficiency (EE), moisture content, antioxidant activity, particle size, Fourier-Transform InfraRed (FT-IR) spectroscopy, X-Ray Diffractometer (XRD), pH and acidity, fat content, peroxide value, and Thiobarbituric Acid (TBA) tests were carried out on samples. Also, texture analyses and sensory evaluation were done on them. The EE of the samples varied from 59%  to 89.53%. The lowest efficiency was observed in T1(5% WPI, 0.5% gingerol), whereas T2 (15% WPI, 2% gingerol) exhibited the highest EE. A progressive increase in gingerol and WPI concentrations reduced moisture content, decreasing from 5.97% in T1 to 5.22% in T9. The peroxide value was measured at 0.47 meq/kg in the control sample, while it decreased to 0.17 meq/kg in the encapsulated treatment T9, indicating improved oxidative stability. The results demonstrate that an increase in gingerol content inside the nanocapsules significantly enhanced antioxidant activity. The nanocapsules ranged in size from 139.1 to 224.1 nm, with a PolyDispersity Index (PDI) varying from 0.209 to  0.238. The sensory evaluation results demonstrated that cheese samples with 0.5% gingerol were much more appealing. The use of WPI as a gingerol coating may improve the beneficial properties of cream cheese throughout a 30-day storage period. The study on nanocapsules showed that gingerol concentrations of 0.5%, 1%, and 2% with 15% WPI were suitable for the cream cheese formulation, with samples being evaluated over a 30-day storage period.

The growing concern for the promotion of health and prevention of disease through improved nutrition has led to numerous attempts to develop food-grade delivery systems to encapsulate, protect and deliver bioactive components.Bioactive components may be utilized for two main purposes, to protect the sensory and nutritive quality of the food and/or to protect the body against chronic and age-related diseases. The delivery of bioactive compounds to various sites within the body is directly affected by particle size so encapsulation of bioactive compounds such as carotenoid pigments, polyphenols and other antioxidants in polymerbased nanoparticles as nanofoods provide simple way to develop novel functional foods that may have physiological benefits or reduce risks of diseases. Because of unique properties of these compounds, polymeric nanoparticles (nanospheres & nanocapsules) enhance the performance of them by improving their solubility and bioavailability, in vitro and in vivo stability, sustained delivery, preventing their unwanted interactions with other food components and protection from physical and chemical degradation etc. Nanoparticles are composed of either synthetic or naturally occurring biodegradable polymers such as poly lactic acid (PLA), chitosan and alginate. Hydogels chitosan and sodium alginate, by virtue of their physiochemical properties and mild gelation conditions have emerged as potential matrices of various bioactive compounds for controlled food-grade delivery through the oral route. Hence, controlled or sustained delivery system is crucial to obtain maximum benefits of using bioactive components as functional foods or nutraceuticals.This paper reviews nanoparticle encapsulation systems with respect to their potential applications as nutrient delivery system in foods.

The application of natural compounds including green tea extract (GTE) in food preparation and pharmaceutical industries is limited. Encapsulation in nanoliposomes could be used as a delivery system to protect these compounds during processing and storage. In this study physicochemical characterization, total phenol content and antibacterial and antioxidant activity of green tea extract encapsulated in nanoliposomes were evaluated. GTE was encapsulated in liposomes by thin film layer method and reached to nanoscale with sonication. The antioxidant activity of nanoliposomal GTE was estimated by DPPH assay. The antibacterial activity of nanoliposomal GTE against Bacillus cereus (ATCC11778), Salmonella typhimurium 138 phage type 2, Escherichia coli O157: H7 and Listeria monocytogenes (ATCC19118) was determined using well diffusion technique. The mean diameter of nanoliposomes was about 44.7±1.9 nm and had 0.203±0.014 polydispersity index. Entrapment efficiency of nanoliposomal GTE under the optimum conditions was 97%. Antibacterial activity of GTE was significantly increased after encapsulation in nanoliposomes. The strongest antibacterial activity of nanoliposomal GTE was seen against L. monocytogenes with an inhibition zone of 16.2 mm while E. coli was the most resistance strain with an inhibition zone of 14 mm. Furthermore, the antioxidant activity of GTE was significantly increased after nanoliposome encapsulation since the IC50 value of nanoliposomal GTE was decreased to 1.78 mg/ml. Nanoencapsulation effectively enhanced beneficial properties of GTE including antimicrobial and antioxidant activities.