Enzymatic synthesis, encapsulation and anti-obesity effect of palm-based medium-and long-chain triacylglycerol functional oil

Medium-and long-chain triacylglycerol (MLCT) is a type of structured lipid that can act to suppress visceral fat accumulation. In the present work, MLCT was synthesized from palm sources and its anti-obesity effect was evaluated in mice prior to its application as powdered oil. This study was aimed to produce a palm-based healthy functional oil in liquid and powdered form that had the ability to reduce body fat accumulation. In the first part of this study, response surface methodology (RSM) with face centered composite design (FCCD) was employed to optimize the palm-based MLCT (P-MLCT) production. The optimized conditions obtained: substrate ratio palm kernel oil: palm oil (PKO:PO) of 90:10 (w/w), reaction time of 7.26 h, reaction temperature of 50 ˚C and 5 % (w/w) Lipozyme TLIM lipase successfully yielded around 60 % MLCT acylglycerol. Subsequently, the influence of P-MLCT on body fat accumulation was evaluated in Diet Induced Obesity (DIO) C57BL/6J mice for 2 and 4 months period, respectively. Blood serum was collected and fat pad (perirenal, mesenteric, epidydymal, and retroperitoneal) were dissected at the end of feeding trials. The 2 months feeding trial revealed that mice fed with P-MLCT attained the lowest total fat pad accumulation. Visceral fat accumulation of P-MLCT fed mice was 0.921 g (7 % P-MLCT) and 3.15 g (30 % P-MLCT) compared to non-enzymatically modified palm kernel: palm oil blend (PKO-PO Blend) having 1.07 g (7 % PKO-PO Blend) and 3.29 g (30 % PKO-PO Blend), and commercial MLCT (C-MLCT) with 1.03 g (7 % C-MLCT) and 3.18 g (30 % C-MLCT). Four months trial showed a more significant reduction (P<0.05) where consumption of 7 % P-MLCT managed to reduce ~30 % of body weight gain and ~37 % of body fat mass, compared to PKO-PO Blend and C-MLCT. Both 2 and 4 months trial resulted in similar trend on the blood serum parameters. P-MLCT was found to be efficient in controlling blood glucose and total triglyceride level, as compared to C-MLCT and PKO-PO Blend. Nevertheless, PKO-PO Blend and P-MLCT lead to a significantly higher (P<0.05) total cholesterol level compared to C-MLCT. Both PKO-PO Blend and P-MLCT when fed for 2 months period resulted in mice having 1.14x (low fat diet) and 1.30x (high fat diet) higher cholesterol level. Similarly, 4 months feeding trial also led to a 1.25x (low fat diet) and 1.40x (high fat diet) increase in cholesterol level. Lastly, P-MLCT powdered oil was developed via microencapsulation process with Maillard Reaction Products (MRP) as the encapsulating agent. MRP was prepared from heat aqueous solution containing mixture of sodium caseinate (SC), soy protein (SP) and maltodextrin (M) prior emulsification with P-MLCT oil and subsequently spray dried. The effect of MRP prepared at various conditions (temperature, incubation time, ratio of SC:SP:M and carbohydrate+protein:water content) on the degree of glycation and the physical properties of emulsion as well as spray dried powder was investigated. It was found that increase in the heat treatment (20 ˚C, 40 ˚C, 60 ˚C, 80 ˚C, 100 ˚C) and incubation time (2 h, 6 h, 8 h) of Maillard reaction led to the elevation of glycation. This subsequently caused a reduction in emulsion droplet size as well as lowering of moisture and surface oil content of the spray dried P-MLCT powder. The emulsion droplet size was reduced from 3.86 um to 0.29 um with the increase in temperature from 20 ˚C to 100 ˚C and 0.51 um to 0.26 um when incubation time was prolonged from 2 h to 8 h. Additionally, moisture content of spray dried powder was 20 % and 12 % lesser when the reaction temperature elevate from 20 ˚C to 100 ˚C and reaction time was extended from 2 h to 8 h. Also, MRP resulted in powder with smoother surface. In summary, P-MLCT oil having ~60 % MLCT acylglycerol can act as healthy functional oil/powder in managing obesity. Both the liquid and powdered P-MLCT oil can be incorporated with ease into various food products to enhance their functionality.

Preview Text IB 2016 8 IR.pdf Download (467kB) | Preview

Actions (login required)

View Item