Natritional and Biochemical Assessment of Curcumin based designer foods

Abstract

The present project was designed to probe the therapeutic potential of indigenously grown turmeric variety (Kasur) to mitigate the threat of hypercholesterolemia. Purposely, turmeric was analyzed nutritionally followed by extraction & quantification of active ingredient i.e. curcumin, its encapsulation, product development and lastly bioefficacy trial. The compositional assessment indicated that turmeric is a good source of minerals especially potassium (K) and calcium (Ca). For optimal extraction of curcumin, three conventional solvents (aqueous ethanol, -methanol & -acetone), each at 35, 50 and 65 min and supercritical carbon dioxide at varying time intervals; 50, 100 & 150 min were employed. The resultant conventional extracts were tested for total phenolic contents (TPCs), 2,2-diphenyl 1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)/ABTS, ferric reducing antioxidant power (FRAP) and iron chelating assays. Afterwards, three best treatments, one from each conventional solvent were selected on account of promising phytochemistry and maximum antioxidant potential. However, the best results were noticed for aqueous ethanolic extract at 65 min; TPC 917.06±10.08 mg GAE/100g, DPPH 65.12±2.87%, FRAP 194.47±8.03 µM Fe2+/g, ABTS 163.14±6.12 µM Trolox/g and iron chelation activity 66.92±2.95%. Furthermore, the selected conventional solvent and supercritical fluid extracts were quantified via HPLC system that showed highest curcumin yield in supercritical fluid extracts i.e. 52.41±2.38 mg/g at 150 min trailed by 46.03±2.15 and 33.62±1.24 mg/g at 100 & 50 min, respectively in comparison to conventional ethanolic, methanolic and acetonic extracts as 31.48±1.35, 28.75±1.09 and 23.19±1.12 mg/g, respectively. On the basis of HPLC analysis, two selected treatments from each extraction mode; aqueous ethanolic extract at 65 min and supercritical carbon dioxide extracts at 150 min were further proceeded for encapsulation using different combinations of maltodextrin (15 & 20 g) and gelatin (2, 4 & 6 g) to enhance the bioavailability of curcumin. Amongst various blends of coating materials, two encapsulates from conventional solvent & supercritical fluid extracts containing 20 g maltodextrin and 6 g gelatin were selected based on their encapsulation efficiency 69.32±2.83 & 73.58±3.16% and in vitro solubility 4.26±0.19 & 4.73±0.23 mg/mL, respectively. In product development plan, four types of breads were prepared using turmeric powder, microencapsulated nutraceuticalCSE and microencapsulated nutraceuticalSFE along with control. During storage, designer bread prototypes were tested for physicochemical aspects (color, texture, volume & TPCs) that imparted significant effect with respect to treatments and storage intervals (0, 24, 48, 72 & 96 hr) along with acceptable hedonic response. The efficacy assessment was conducted on male Sprague Dawley rats to evaluate the bioavailability and therapeutic effectiveness of the active ingredient. In bioavailability phase, microencapsulated nutraceuticalSFE supplemented diet resulted in maximum plasma concentration of curcumin at 100 min as 529.31±8.73 µg/mL followed by 462.98±7.25 & 385.76±5.01 µg/mL at 150 & 200 min, respectively. During bioevaluation trial, two simultaneous studies namely Study I (normal rats) and Study II (hypercholesterolemic rats) were carried out for 60 days. Each study was further splitted into four groups to ensure the provision of selected diets; control, turmeric powder (3%), microencapsulated nutraceuticalCSE (1%) and microencapsulated nutraceuticalSFE (0.5%) to respective groups. In both studies, feed & drink intakes and weight gain affected significantly. The provision of microencapsulated nutraceuticalSFE supplemented diet caused significant reduction in serum cholesterol, LDL and triglycerides as 5.42 & 12.81, 7.25 & 15.42 and 3.17 & 9.38% in study I & II, correspondingly. Additionally, HDL explicated significant rise in Study II whereas, non-momentous increment was noticed in Study I. Nonetheless, curcumin based diets presented pronounced decrement in serum glucose concentration in response to enhancement in insulin levels. Likewise, glutathione as a probe of endogenous antioxidant status showed significant elevation along with simultaneous decrease in lipid peroxidation (TBARS) in animals fed on microencapsulated nutraceuticalCSE and microencapsulated nutraceuticalSFE enriched diets. Moreover, liver & kidney biomarkers and hematological aspects were within normal ranges. Conclusively, inclusion of microencapsulated curcumin in dietary therapy has proven effective to alleviate hyperlipidemia.