1.1 Introduction
Enzymes are biological catalysts (also known as biocatalysts) that speed up biochemical reactions in living organisms. They are essential components of animals, plants and microorganisms, due to the fact that they catalyze and co-ordinate the complex reactions of cellular metabolism. They can also be extracted from cells and then used to catalyze a wide range of commercially important processes. For example, they have important roles in the production of sweetening agents and the modification of antibiotics, they are used in washing powders and various cleaning products, and they play a key role in analytical devices and assays that have clinical, forensic and environmental applications.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Enzymes are the complex protein molecules, often called biocatalysts, which are produced by living cells. They are highly specific both in the reactions that they catalyze and in their choice of reactants, which are known as substrates. One of the most common advantages of enzymes is their ability to function continuously even after their removal or separation from the cells. The word ‘enzyme' was first used by the German physiologist Wilhelm Kühne in 1878, when he was describing the ability of yeast to produce alcohol from sugars, and it is derived from the Greek words en (meaning ‘within') and zume (meaning ‘yeast').
The primary aim of this project is center on the determination of the catalytic and specific activities of enzymes in fermentation of starch from maize. These enzymes are DIATASE, MALTASE and ZYMASE. This determination study is made possible through certain unique properties which these collections of enzymes possess.
Speaking in concrete terms, ENZYMES serve as bio-catalysts, speeding up chemical reactions, like those involved with fermentation of starch. Enzyme molecules accelerate the rate of reactions, often by many orders of magnitude, thereby allowing the substance involved undergo a chemical breakdown.
Enzymes in fermentation of starch go about their work in an ASSEMBLY-LINE fashion; each enzyme performing a specific task at a particular stage of the fermentation process. For instance, the enzyme-MALTASE, breaks down MALTASE into two isomeric fermentable sugars namely Glucose and Fructose; thereby preparing another stage for another enzyme to act during the fermentation process. Enzymes in fermentation process especially in starch; perform their work at blinding speed.
A single molecule of enzyme can catalyze thousands of chemical reactions per second. This is because enzymes in fermentation reaction particularly in starch; have a marked ability to accelerate the reaction and also to promote the specific processes involved under the chemically mild conditions which prevails in the fermentation process.
In all ways, these enzymes readily make essentials physiochemical contributions to the fermentation process by virtue of their organized and involved three dimensional structure which reveals certain regions on the enzyme surface where small solute molecules or ions can bind reversibly. Such solutes are called LIGANDS; a farm borrowed from Organometalic Chemistry.
There may be many ligard binding sites on the surface of an enzyme, but each site usually possesses the power to bind only a limited range of ligards, by virtue of the character of the site. The term “CHARACTER” is there used to cover not only the three-dimensional shape of the site but also its charge characteristics and to what degree if is hydrophobic or hydrophilic.
The character of a binding site is clearly a function of the amino acid side chains that are brought together there by the folding of the polypeptide chain. Enzymes are distinguished from other protein molecules by having ACTIVE SITES. The substrate binds at the active site of its enzyme in much the same way as other ligards might do, but once bound there, a chemical reaction ensues because of the special nature of the enzyme active site in respect to their catalysis and specificity in fermentation bioprocess.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Determination of the Activities and Specificity of Enzymes in Fermentation of Starch from Maize.
1.3 Statement of Problems
Investigation revealed that the cost of the enzymes and the inability of small scale brewers to understand and exploit the chemistry of fermentation by enzymic action. Demand grew and as fermentation technology developed, the competitive cost of microbial enzymes was recognized and they became more widely used. Compared with enzymes from plant and animal sources, microbial enzymes have economic, technical and ethical advantages.
1.4 Aim and Objectives of Study
The aim of the study is to determine the Activities and Specificity of Enzymes in Fermentation of Starch from Maize. In achieving this aim, the following specific objectives were laid out as follows:
- To prepare the enzymes through the microbial fermentation of malt/sermination barley extracts in a culture media and a seed fomenter.
- To show the chemistry of fermentation process in starch by enzymic conversion.
- To show the relevance and usefulness of enzymes in industrial fermentation.
1.5 Significance of Study
The importance of the work is centered on the catalytic and specific activities of enzymes in fermentation of starch for industrial usage. This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.6 Scope of Study
The scope of the research is focused on the determination of the activities and specificity of enzymes in fermentation of starch from maize.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).