Psyllium preparations

FIGURE 4.3 Surface structures of psyllium preparations determined by SEM. (A) Psyllium treated with 0 enzyme, (B) psyllium treated with 120 units of Shearzyme 500 L, (C) raw psyllium, and (D) psyllium treated with Viscozyme L at a level of 30 units/g psyllium, under the experimental conditions (A and B are adapted from Yu, 2003b, while C and D are adapted from Yu et al., 2003). 

FIGURE 4.6 Effect of solid-state enzyme treatment on hypolipidemic activities of psyllium. Plasma lipid concentrations in hamsters were measured at day 35. Values are mean SEM (vertical bars) for nine animals per group. Within each response parameter, values not sharing common letters are significantly different, P<0.05. Modified Psy-1 and modified Psy-2 represent the two modified psyllium preparations using the Viscozyme L and the Shearzyme 500 L, respectively, under the solid-state reaction conditions (re-drawn from Allen et al., 2004). 

Kritchevsky, D., Tepper, S. A., and Klurfeld, D. M. (1995). Influence of psyllium preparations on plasma and liver lipids of cholesterol-fed rats. Artery 21, 303-311. 

Psyllium preparation (polysaccharide) Plantago psyllium (Plantaginaceae) HypoGlc (NIDDM human) [anti-constipation, anti-haemorrhoid, water-absorbant]... 

An ispaghula preparation (Vi-Siblin S) was found to have no significant effect on serum digoxin levels of 16 geriatric patients.- The same lack of effect was seen in another study in 15 patients given 3.6 g of a psyllium preparation (Metamucil) three times a day. ... 

Information is very limited and the general importance of this interaction is uncertain, but it would now seem prudent to bear this interaction in mind in patients given ispaghula or psyllium preparations. If an interaction is suspected consider monitoring lithium levels and separating the administration of the two drugs by at least an hour, or use an alternative laxative. 

Meta-analyses of psyllium preparations have not reported any adverse events associated with clinical trials of psyllium (Anderson et al. 2000 Brown et al. 1999 Olson et al. 1997). 

Psyllium has attracted an increasing amount of interest to be used in different biomedical applications in the last two decades. The inherent ability of psyllium to absorb water and its gelling properties has maximized the value of psyllium incorporation in varieties of food formulations and other applications. The psyllium preparations with proper physiological functions are also high in demand due to FDA approval to include health claims of reducing heart disease. Numerous studies (13, 14, 15, 16, IT) have been made to improve psyllium physical and chemical properties and to maximize the use of this highly useful material... 

A novel procedure was developed to improve psyllium functionality by conducting a solid-state enzyme reaction. The procedure requires no special equipment/operation (such as freeze dry) and could be carried out without using any additional chemicals. To evaluate the solid-state enzymatic procedure, modified psyllium preparations were produced under selected reaction conditions, and analyzed for their water-absorbing capacity, gelling capacity, particle surface structure, and soluble and insoluble fiber contents. The results showed that structural modification improved psyllium functionality. Modified psyllium preparations had reduced water-absorbing capacity and less gelling ability. The reduced water-absorbing capacity may be explained by the decreased surface area of psyllium particles. In addition, the solid-state enzymatic treatments had much less effects on soluble fiber contents than the liquid phase enzymatic reactions. 

In this chapter, a solid-state enzymatic procedure for psyllium modification and the novel psyllium preparations with improved functionalities is discussed. This procedure requires no special operation, equipments and hazardous chemicals. This procedure also produces no chemical wastes. 

Gelling properties were analyzed using a TA-XT2 texture analyzer (Texture Technologies Corp, Scarsdale, NY), with a 25 mm diameter probe (72). 1.50 g of each psyllium preparation was added into 30 ml distilled deionized water and stirred for 30 seconds. After setting for 24 hours, gel samples were subjected to a double compression test. Measurements were performed with a pretest speed of 2.0 mm/sec, a test speed of 5.0 mm/sec, a post test speed of 5.0 mm/sec, and a distance of 6 mm. All measurements were made in triplicate. The results were expressed as the mean SD in gram force for Hardness and Adhesiveness. 

Scanning electron microscope (SEM) analysis was conducted to determine the surface structures of modified psyllium preparations using a Philips SEM 505 instrument (Holland). 

Figure L Modified psyllium products from solid-state enzymatic reaction vs. conventional liquid-state enzymatic reaction. A = modified psyllium at the end ofsolid-state reaction, and B = modified psyllium at the end of liquid state enzymatic reaction. Psyllium preparation A requires no additional water-removing step, while psyllium preparation B requires additional step to remove...

Psyllium prepared by the solid-state enzymatic procedure had reduced water-absorbing capacity (Figure 2). Increased levels of enzymes were not always associated with further reduction in water absorbing capacity. The lowest water-uptaking rate of modified psyllium by the solid-state procedure... 

To better understand the solid-state enzymatic reactions, the surface structures of the modified psyllium were analyzed and compared to that of raw psyllium using a scanning electron microscope (SEM). SEM results showed that modified psyllium had a smoother surface than raw psyllium (Figure 5). In another words, solid-state enzymatic treatment reduced the total surface area of the psyllium particles. This reduction may explain the reduced water-uptaking rate of the modified psyllium preparations, but not the improved gelling properties. More studies are needed to evaluate the effects of solid-state enzymatic modification on gel forming properties of psyllium. 

Figure 5. Surface structures of psyllium preparations determined by SEM. A...

The soluble and insoluble fiber contents of the modified psyllium preparations were measured to estimate the effects of structural modification on the biological activities of psyllium including cholesterol-lowing activity, since the soluble fibers were believed to contribute to the cholesterol-lowing activity of raw psyllium 1, 8, 9). Compared to the liquid-phase enzyme reaction, solid-state enzymatic treatments showed less effect on soluble fiber contents of the modified psyllium preparations (Table 1), while both procedures had minor effects on insoluble fiber contents. Similar ratios of the selected enzyme resulted in about 15% reduction in soluble fiber content by the conventional liquid-phase enzymatic reaction (i), while only had less than 4% reduction in soluble fiber content under the solid-state reaction conditions. This is another advantage of the solid-state enzymatic procedure vs. the liquid-phase enzymatic reaction described previously by Yu et al. (/). 

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