Inhibited starch

Extracts from 152 plant species, representing 46 different families, were screened for effects on tobacco mosaic virus (TMV) replication in cucumber cotyledons. Twenty species have shown enough activity to warrant further study. Several members of the Caprifoliaceae family increased virus replication. An extract of Lonicera involucrata enlarged the virus lesions in local lesion hosts and produced a thirty fold increase in virus titer, but had no effect on virus replication in systemic hosts. The active material appears to affect the virus defense mechanism of local lesion hosts. An extract of common geranium is an active virus inhibitor. It inactivates TMV and TMV-RNA (ribonucleic acid) in vitro by forming non-infectious complexes. In vivo, it also inhibited starch lesion formation in cucumber cotyledons incited by TMV infection. 

These solve the shelf life problem by having a very low water activity aided by the quantity of dried fruit that they contain. The fat content and the low water activity inhibit starch retrogradation. 

Mathews, J.N., P.R. Flatt, and Y.H. Abdel-Wahab. 2006. Asparagus adscendens (shweta musaU) stimulates insulin secretion, insulin action and inhibits starch digestion. Br. /. Nutr. 95(3) 576-581. 

These include cross linked or inhibited starches, hydroxypropylated starches, phosphorylated starches, starch succinates, grafted starches, and carboxymethyl starch. ... 

Owing to this strongly branched structure of amylopectin, its properties differ from those of amylose because of the large size of the amylopechn molecules and their structure, for example, retrogradahon proceeds more slowly than in amylose and gel formation is inhibited. Starches consisting mainly of amylopechn (wax starches) are considered not to be gelating, but they usually show compact and rubbery textures. Amylopechn heated in water swells and forms a paste, it absorbs iodine poorly (around 0.6%), and stains violet or red-brown. 

Potassium is required for enzyme activity in a few special cases, the most widely studied example of which is the enzyme pymvate kinase. In plants it is required for protein and starch synthesis. Potassium is also involved in water and nutrient transport within and into the plant, and has a role in photosynthesis. Although sodium and potassium are similar in their inorganic chemical behavior, these ions are different in their physiological activities. In fact, their functions are often mutually antagonistic. For example, increases both the respiration rate in muscle tissue and the rate of protein synthesis, whereas inhibits both processes (42). 

Starch acetates may have low or high DS. The industrial importance of low DS acetates results from their abiUty to stabilize aqueous polymer sols. Low DS acetates inhibit association of amylose polymers and reduce the association of the longer outer chains of amylopectin. These properties are important in food appHcations. Highly derivatized starches (DS 2—3) are useful because of their solubiHty in organic solvents and abiHty to form films and fibers. 

Low DS starch acetates have reduced gelatinization temperature ranges and reduced tendency to retrograde after pasting and cooling. Gelling may be completely inhibited if the DS is sufficiently high. Low DS starch acetate polymers also form films which are useful in textile and paper manufacture. 

One example of a naturally occurring diazirine, duazomycin A (137 Scheme 11.20), has been reported, isolated in 1985 from a Streptomyces species during a screen for herbicidal compounds [196], It was fotind to inhibit de novo starch synthesis and it was suggested that this is due to direct inhibition of protein synthesis. Duazomycin A is structurally related to 6-diazo-5-oxo-L-norleucine (138), also reported as a natural product from Streptomyces [197], which acts as a glutamine antagonist and inhibits purine biosynthesis [198],... 

Aqueous geranium extract inhibited TMV starch lesion formation in cucumber cotyledons. Starch lesions were completely inhibited by vacuum infiltrating effective dosages at any time between 1 and 33 hours after virus inoculation. Between 33 and 72 hours, inhibition decreased progressively. The active ingredient in the geranium extract was identified by means of ultraviolet absorption spectrum and... 

Active TMV starch lesion-inhibiting component isolated from geranium leaves on paper chromatograms... 

Lesion formation represents a host response to virus infection. Factors preventing the formation of starch lesions incited by the virus do not necessarily mean that virus replication is inhibited at the same time. Therefore, the total virus titer in cotyledon samples treated with different concentrations of tannic acid was determined (Figure... 

Acarbose and Miglitol These agents are specific inhibitors of intestinal glucosidases and reduce the conversion of sucrose and starch to glucose. Their main effect is a delay, not a complete inhibition, of the absorption of carbohydrates. Postprandial blood sugar excursions are effectively reduced. Because a small portion of the carbohydrates enters the colon, their microbial degradation frequently causes flatulence or... 

Diabetic patients have reduced antioxidant defences and suffer from an increased risk of free radical-mediated diseases such as coronary heart disease. EC has a pronounced insulin-like effect on erythrocyte membrane-bound acetylcholinesterase in type II diabetic patients (Rizvi and Zaid, 2001). Tea polyphenols were shown to possess anti-diabetic activity and to be effective both in the prevention and treatment of diabetes (Choi et al, 1998 Yang et al, 1999). The main mechanism by which tea polyphenols appear to lower serum glucose levels is via the inhibition of the activity of the starch digesting enzyme, amylase. Tea inhibits both salivary and intestinal amylase, so that starch is broken down more slowly and the rise in serum glucose is thus reduced. In addition, tea may affect the intestinal absorption of glucose. 

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