Effect of different pretreatments on antioxidant activity of oats grown in the Himalayan region.

In this work the different varieties of oats were subjected to three pre-treatments such as germination, sand roasting and γ-irradiation. The pretreated oat grains were evaluated for phenolic content, flavonoid content and antioxidant activity. RP-HPLC displayed that the amount of ferulic acid, chlorogenic acid, kaempferol, ellagic acid and epicatechin in native, roasted and γ-irradiated oats varied in the range of 2.51-3.23, 0.97-1.89, 4.35-5.33, 1.56-2.197 and 3.387-10.8 µg/100 g, respectively. Total phenolic content (TPC) expressed as µg GAE/g and µg FAE/g and total flavonoid content (TFC) expressed as µg rutin equivalent/g was found highest in germinated samples. Study reported increase in antioxidant activity in the following order; γ-irradiation > germination > roasting > native. It was concluded that the different pretreatments enhanced antioxidant properties of the oat grains therefore can be efficiently utilized as food or functional ingredient in various food systems.

Ultrasonication as an innovative approach to tailor the apple seed proteins into nanosize: Effect on protein structural and functional properties.

In this study, protein was extracted from the apple seed flour using alkali-acid precipitation method. The main objective of this study was to evaluate the impact of ultrasonication on structural and techno-functional properties of apple seed protein. Both native (N-protein) and ultra-sonicated protein (US-protein) were characterized for size, zeta potential, structure, protein pattern, crystallinity, thermal stability and functional properties. The results revealed that the hydrodynamic diameter of N-protein and US-protein was 1.2 µm and 484 nm while zeta potential was -11 and -19 mV, respectively. Fourier transform infrared-spectroscopy and X-ray diffraction analysis showed change in the conformational characteristics and functional groups of proteins after nano-reduction. SEM revealed change in the surface morphology of protein molecule upon ultrasonication. Differential scanning calorimetry showed decreased denaturation temperature for US-protein compared to N-protein . SDS-PAGE depicted no change in protein pattern upon ultrasonication. Ultrasonicated protein exhibited increased functional properties like emulsification, foaming, hydrophobicity and oil absorbing properties and hence can be efficiently used as functional ingredient in food and nutraceutical industry.

Ferulic acid loaded pickering emulsions stabilized by resistant starch nanoparticles using ultrasonication: Characterization, in vitro release and nutraceutical potential.

The use of starch based nanoparticles have gained momentum in stabilizing pickering emulsions for it's numerous advantages. In present study resistant starch (RS) was isolated from lotus stem using enzymatic digestion and subjected to nanoprecipitation and ultrasonication to yield resistant starch nanoparticles (RSN). RSN of varying concentrations (2%, 10% and 20%) were used to stabilize the flax seed-oil water mixture to form pickering emulsions. The emulsions were used to nanoencapsulate ferulic acid (FA) - a well known bioactive via ultrasonication. The emulsions were lyophilized to form FA loaded lyophilized pickering emulsion (FA-LPE). The FA-LPE (2%, 10 % and 20%) were characterized using dynamic light scattering (DLS), light microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and attenuated total reflectance fourier transform infra-spectroscopy (ATR-FTIR). AFM showed FA-LPE as spherical droplets embedded in the matrix with maximum peak height of 8.47 nm and maximum pit height of 1.69 nm. SEM presented FA-LPE as an irregular and continuous surface having multiple folds and holes. The ATR-FTIR spectra of all the samples displayed peaks of C = C aromatic rings of FA at 1600 cm-1 and 1439 cm-1, signifying successful encapsulation. In vitro release assay displayed more controlled release of FA from FA-LPE (20%). Bioactivity of FA-LPE was evaluated in terms of anti-cancer, anti-diabetic, angiotensin converting enzyme (ACE) inhibition and prevention against oxidative damage under simulated gastro-intestinal conditions (SGID). The bioactivity of FA-LPE (20%) was significantly higher than FA-LPE (2%) and FA-LPE (10%). Key findings reveal that pickering emulsions can prevent FA under harsh SGID conditions and provide an approach to facilitate the design of pickering emulsions with high stability for nutraceutical delivery in food and supplement products.

ß-Glucan from mushrooms and dates as a wall material for targeted delivery of model bioactive compound: Nutraceutical profiling and bioavailability.

Rutin was nano-encapsulated in date [En-Ru(D)] and mushroom [En-Ru(M)] ß-glucan matrix to protect it from the harsh gastrointestinal environment and to enhance its bioavailability and biological activity upon digestion. The encapsulation was carried using green technology i.e., ultra-sonication. The En-Ru(D) and En-Ru (M) showed the hydrodynamic diameter of 314.04 and 482.21 nm with polydispersity index of 0.21 and 0.33. The in vitro release behaviour followed the Higuchi model. The antimicrobial activity of En-Ru(D) and En-Ru(M) were evaluated against gram negative E. coli (ATCC 25922) and gram positive (Staphylococcus aureus) bacteria. Furthermore, En-Ru(D) and En-Ru(M) exhibited increased bioavailability of rutin in intestinal fluid with retention of anti-obesity and antioxidant activities after digestion (p < 0.05). Therefore, ß-glucan matrix can efficiently encapsulate flavonoids and regulate the release of functional bioactive ingredients in the simulated human digestive conditions.

Nutraceutical profiling of surimi gel containing ß-glucan stabilized virgin coconut oil with and without antioxidants after simulated gastro-intestinal digestion.

Surimi gels containing ß-glucan stabilized virgin coconut oil (VCO) were subjected to simulated gastrointestinal digestion and the resulting digest was analyzed for nutraceutical properties. ß-glucan stabilized VCO nanoemulsion (ßG-V-N) remarkably improved antioxidant activities of the surimi digest. When epigallocatechin gallate (EGCG) was added in nanoemulsion, the surimi digest showed the highest antioxidant activities. Antidiabetic activity of the digest was also improved by the addition of ßG-V-N comprising EGCG. Nevertheless, the addition of ßG-V-N lowered ACE inhibitory activity of surimi digest. The surimi digest from the gel added with ßG-V-N possessed an inhibitory effect on five cancer cell lines including HEK (Human embryonic kidney 293 cells), MCF-7 (breast cancer cell line), U87 (human glioma), HeLa (human cervical cancer), and IMR-32 (human neuroblastoma), regardless of EGCG or α-tocopherol incorporated. This study demonstrated that surimi gel supplemented with ßG-V-N in the presence of EGCG exhibited nutraceutical potential and could be used as a functional food.