Enzymatic degradation, PEAs

In this chapter we describe the use of pea seeds to express the bacterial enzyme a-amylase. Bacterial exoenzymes like the heat stable a-amylase from Bacillus licheni-formis are important for starch hydrolysis in the food industry. The enzymatic properties of a-amylase are well understood [13,14], it is one of the most thermostable enzymes in nature and it is the most commonly used enzyme in biotechnological processes. Although fermentation in bacteria allows highly efficient enzyme production, plant-based synthesis allows in situ enzymatic activity to degrade endogenous reserve starch, as shown in experiments with non-crop plants performed under greenhouse conditions [12,15]. Finally, the quantitative and sensitive detection of a-amylase activ-... 

All those commercial synthetic absorbable sutures fabricated from the gly-colide, lactide, e-caprolactone, p-dioxanone, and trimethylene carbonate building blocks can only be degraded via pure hydrolysis. Although it has been suggested that enzymes are involved, the issue is remains unresolved and controversial. There were no truly enzymatically biodegradable synthetic absorbable fibers on the market until the reported studies of amino add-based poly(ester amide)s (AA-PEA). 

The use of proteins as raw material for personal and home care products has been known for more than 60 years [58]. Both animal (e.g. leather waste) and plant-based proteins are available as raw materials. Nowadays mostly plant-based proteins (e.g. from wheat, soya bean, rice, peas) are used. Typically the natural proteins are degraded by hydrolysis (either chemically or enzymatically) and the respective protein hydrolysates are obtained. After purification and work-up they are used for skin and hair care formulations. The main claims are protection and care for hair and skin. Subsequent quarternization of the protein hydrolysates leads to products with high substantivity and conditioning effects, whereas acylation of the protein hydrolysates with fatty acids results in protein surfactants, the so-called protein fatty acid condensates. In the latter case, as already described for the sugar-based surfactants, the products are based completely on natural raw materials, namely fatty acids (from vegetable oil) and the protein or protein hydrolysate as the hydrophilic part in the surfactant molecule (Figure 4.6). The... 

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