Tailored synbiotic powder (functional food) to prevent hyperphosphataemia (kidney disorder)

Abstract

Hyperphosphataemia is treated with phosphate binders, which can cause adverse effects. Spray-dried synbiotic powder (SP) composed of Lactobacillus casei JCM1134 (a phosphate-accumulating organism; PAO) and Aloe vera is potentially a safer alternative for efficient phosphate removal. In this study, a novel strategy was developed; lysine-derivatized deacetylated A. vera (DAVK) was synthesised and fabricated on phosphate-deficient PAO (PDP) for efficient phosphate transfer and then spray-dried with the supernatant of DAV centrifugation to form a sacrificial layer on PDP for SP integrity during gastric passage. In vitro experiments revealed that PAO removed only 1.6% of the phosphate from synthetic media, whereas SP removed 89%, 87%, and 67% (w/v) of the phosphate from milk, soft drink, and synthetic media, respectively, confirming the protective role of A. vera and efficient phosphate transport. Compared with commercial binders, SP effectively removed phosphate from synthetic media, whereas SP and CaCO₃ exhibited comparative results for milk and soft drink. Importantly, CaCO₃ caused hypercalcaemia. Thus, the described SP presents a promising tool to prevent hyperphosphataemia. This study also revealed a novel factor: diets of patients with chronic kidney disease should be monitored to determine the optimal phosphate binders, as phosphate removal performance depends on the accessible phosphate forms.

Figure 1

Experimental procedure for spray dried synbiotic powder (SP) formulation.

Figure 2

Fourier-transform infrared spectroscopy (FT-IR) analysis of Aloe vera modification. (a) Untreated Aloe vera, (b) deacetylated A. vera (DAV), and (c) lysine derivative of DAV (DAVK).

Figure 3

Unreacted lysine in lysine derivative of deacylatisation Aloe vera (DAVK) over time. In the reaction mixture, deacylated A. vera (DAV, 1 g) and lysine (70 mg) reacted under optimised conditions and significant p-values (p < 0.002 by two-tailed ANOVA, with n = 3 and alpha value of 0.95) were obtained and the standard errors are shown as error bars.

Figure 4

Scanning electron microscopy (SEM) analysis of Lactobacillus casei JCM1134 as phosphate-deficient cells (PDP) and under stepwise encapsulation conditions. (a) PDP, (b) lysine (K) derivative of deacetylated A. vera (DAVK)-encapsulated PDP, and (c) spray-dried synbiotic formulation (SP).

Figure 5

Comparison of spray-dried synbiotic formulation with commercial phosphate binders. Phosphate-rich foods that were used included milk, a soft drink, and synthetic media. Significant p-values (p < 0.05 by two-tailed ANOVA, with n = 3 and alpha value of 0.95) were obtained and standard errors are shown as error bars.

Figure 6

A schematic diagram of a gastrointestinal simulation system for the evaluation of different phosphate removing agents from the in vitro broth, which contains phosphate-rich sources.