USEFULNESS OF ALGAE AS FOOD AND MEDICINE TO OUR SOCIETY

1.1 Introduction

Algae are photosynthetic organisms which constitute a total of about twenty-five to thirty thousand species with a great diversity of forms and sizes ranging from unicellular microscopic organisms (microalgae) to multicellular organisms of great sizes (Arun et al., 2012). Growing demand for natural food and special purpose foods increases interest in traditional production methods, largely based on the addition of naturally occurring plants or their metabolites. Extracts from seaweed, macro and microalgae are rich in compounds that have well-documented antioxidant properties, therefore they are increasingly used in food production.

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, Research hypothesis and questions, Limitations of the Study and Definition of technical terms.

1.2 Background of Study

Agar is widely used in paper manufacturing, culture media, packaging material, photography, leather industry, plywood manufacturing, preservation of foodstuffs, dairy industry, cosmetics industry and pharmaceutical industry. Carrageenan is employed in food industry. Its value in the manufacture of sausages, corned beef, meat balls, ham, preparations of poultry and fish, chocolates, dessert gels, ice creams, juice concentrates, marmalade, sardine sauces is well known. It is also used in the manufacturing of non-food items like beer, air fresheners, textiles, toothpastes, hair shampoos, tissues, culture media, fungicides, etc. The applications of alginate find place in frozen foods, pastry fillings, syrups, bakery icings, dry mixes, meringues, frozen desserts, instant puddings, cooked puddings, chiffons, pie and pastry fillings, dessert gels, fabricated foods, salad dressings, meat and flavour sauces.

Algae can double every few hours during their exponential growth period (Matting, 1996). During the peak growth phase, some icroalgae can double their growth even 3.5hrs (Christi, 2007). Marine organisms are a rich soruce of structurally novel and biological active metabolites (Borowitzka et.al., 1992; Ely et al., 2004). Secondary metabolites produced by algae may be potential bioactive compounds of interest in the pharmaceutical industries (Febles et al., 1995). Marine algae are an important cash crop in different countries. They are used as food stuff in many countries such as Asian and china for centuries because they contain some phytonutriets such as carotenoids, dietary fibres, protein, essential fatty acids, vitamins, mineral and carbohydrates (Norziah and Ching, 2000). Many chemically unique compounds have been isolated form marine origin with various biologically activities and some of them are still under investigation and are equally been used to develop new pharmaceutical (Febles et al., 1995; Lima-Filho et al., 2002). The cell extract and active component of various algae have been reported to have antibacterial activities in vitro against Gram-positive and Gram-negative bacteria (Borowitzka et al., 1992). Green algae extract from diatoms and dinoflagelate have been reported to have antifungi activities by Borowitzka et al., (1992) and Morean (1988). The search for similar antimicrobial activity in other algae species has gained importance in recent years due to growing worldwide concern about antibiotic resistant microorganisms. Efforts are been made to extract substances with antibacterial, antiviral, antifungi enzymes inhibitory, immunosuppressive and cytotoxic and algicidal properties from low cost algal biomass (Knubel et al.,1990) and (Jaki et al., 1999). Some algal species such as SpirIulina has been reported to hinder oxidative damage by scavenging free radicals and active oxygen and therefore can indirectly reduce cancer formation in human (Halliwel, 1989; and Kok, 1990).

Microalgae exhibit notable biodiversity they can be found as individual cells, as colonies or as extended filaments. They account for the basic of food chain in aquatic ecosystems. They have the capacity to take up water and carbon (IV) oxide that with the aid of solar energy are used to synthesize complex organic compounds which are subsequently accumulated and/or secreted as primary or secondary metabolites (Arun et al., 2012). They are uniformly distributed throughout the biosphere where they have adapted to survival under a large spectrum of environmental stress which includes heat, cold drought, salinity, photooxidation, anaerobiosis, osmotic pressure and ultra violet exposure (Tandeau-de-marsac, 1993). They may equally grow under all environmental condition ranging from fresh water to extreme salinity.

Microalgae have meanwhile been found to produce antibiotic. A large number of microalgae extract and/or extracellular products have been proven to have antibacterial, antifungi, anti protozoal and antiplasmodial activities (Kellan, 2004) and (Ghasemi, 2004). The antimicrobial activity of microalgae has attributed to compounds belonging to several chemical classes including indole, terpenes, actogenins, phenols, fatty acids and volatile halogenated hydrocarbons (Mayer, 2001-2002) and (Cardozo, 2007). Microalgae cell-free extracts are already being tested as additives for food formulation in attempts to replace antimicrobial compounds of synthetic origin currently in use, these includes sub-therapentical dose of antibiotics employed as prophylactic measure in animal breeding (Tramper, 2003).

Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Usefulness of Algae as Food and Medicine to Our Society.

1.3 Statement of Problems

Many human body substances require particular mineral elements as part(s) of their respective structure. Examples are iron for hemoglobin and iodine for thyroxine. For our bodies to function, we use proteins called enzymes. Most enzymes require one or more coenzymatic factors; these coenzymatic factors are usually one or more metal cations. Chronic dietary shortages or disease-related mineral depletions can produce both specific and general disease conditions: Iodine shortage results in varying degrees of thyroid dysfunction; poor absorption of dietary calcium can result in osteoporosis. Adequate residential body mineral supplies are critical for optimal body system functioning. It was observed that the notion that non-specific disease categories such as Chronic Fatigue, lack of energy, subclinical depression and depressed immunity are probably due to inadequate minerals either in the diet or in the body.

1.4 Aim and Objectives of Study

The aim of the study is to examine the Usefulness of Algae as Food and Medicine to Our Society. In achieving this aim, the following specific objectives were laid out as follows:

1. To undergo the extraction yield from different algae;
2. To find out the Antioxidant Activity of Algae; and
3. To determine the medicinal usefulness of Algae.

1.5 Research Questions

The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:

• What is the extraction yield from different algae?
• What is the medicinal usefulness of Algae (Sea weeds)?
• What is the Antioxidant Activity of Algae?
• Can algae serve as food and medicine to the Society?

1.6 Significance of Study

The study will be of great importance to researchers in the field of medical research on the use of algae extract to reduce the prevalence of certain chronic diseases like HIV\\AIDS, Cancer and other bacterial infections. 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.

1.7 Scope of Study

The scope of this research is focused on the Usefulness of Algae as Food and Medicine to Our Nigeria Society.

1.8 Limitations of the Study

During the course of this study, many things militated against its completion, some of which are:

1. 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.
2. Research material: availability of research material is a major setback to the scope of the study.
3. Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
4. 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).