1.0 Introduction
1.1 Background of Study
Peanut (Arachis hypogaea L.) is an important food, as well as an oilseed crop of the tropical and subtropical world. Peanut processing for a variety of edible products (peanut butter, milk, roasted snack peanuts, peanut oil and other value added products) is being done in various developed, as well as developing countries. Peanut skins are low value by-products of peanut blanching and roasting operations; and are currently used as an ingredient of animal ration up to a certain limit. Research has indicated that some natural phenolic compounds can be extracted from peanut oils and hulls, like proanthocyanidins; caffeic acid, chlorogenic acid, ferulic acid, coumaric acid, flavonoids (catechins and procyanidins), and stilbene (resveratrol); and ethyl protocatechuate. Thus, peanut oil may be utilized as a source of natural antioxidants that may have commercial application in a variety of food products. Peanut stilbenoids show to play roles in plant defense mechanisms; they were evaluated for their effects on economically important plant path-ogenic fungi of the genera Colletotrichum, Botry-tis, Fusarium, and Phomopsis (Sobolev et al., 2011). The aims of this study are detection of active ingredients in peanut oils (Arachis hypogea L.) as well as evaluating the antibacterial activity against pathogenic bacteria.
Enterobacteriaceae is a large family of bacteria commonly affecting the stomach. The name is derived from the prefix "entero-", meaning intestine; "bacteria", meaning bacteria; and "ceae", meaning family or group. It includes many of the more familiar pathogens, such as Salmonella and Escherichia coli. There is a growing interest in natural antioxidants found in plants because of the worldwide trend toward the use of natural additives in foods, beverages and cosmetics. Herbs and spices are one of the most important targets to search for natural antioxidants from the point of view of safety (Yanishlieva et al., 2006).
The antioxidants can be of synthetic or natural origin. Synthetic antioxidants such as butylated hydroxyl anisole (BHA), butylated hydroxyl toluene (BHT), tert-butyl hydroquinone (TBHQ), and propyl gallate (PG) have been widely used in meat and poultry products (Jayathilakan et al., 2007). The demand for natural antioxidants, especially of plant origin has increased in recent years due to the growing concern among consumers about these synthetic antioxidants because of their potential toxicological effects (Nunez de Gonzalez et al., 2008).
1.2 Statement of Problems
The study reveals the following problems associated with antibacterial and antioxidant activities of peanut oil;
- Lack proper information about the antioxidant potential of peanut oil extract obtained by various methods,
- Inadequate information relating to the identification of the effect of various solvents on extractability of total phenolic compounds from the peanut oil,
- Inadequate information relating to the evaluation of the effect of peanut oil extracts on oxidative stability of peanut oils.
1.3 Objectives of Study
The aim of this study was to identify and determine the antioxidant activity of peanut. Therefore, the objectives of this research were:
- To study the antioxidant potential of peanut oil extract obtained by various methods,
- To identify the effect of various solvents on extractability of total phenolic compounds from the peanut oil and,
- To evaluate the effect of peanut oil extracts on oxidative stability of peanut oils.
1.4 Significance of the Study
This research work when completed and implemented it will help prevent heart disease and lower cholesterol and also to reduce fatty build up in blood vessels.
Besides, the study will serve as reference material for subsequent researcher in the field or related topics.
1.5 Scope of Study
The study focuses on the antibacterial and antioxidant activities, oxidative stability and extractability of total phenolic compounds from the peanut oil.
1.6 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.
- Establishment Policies: Establishment policies posed a serious limitation as most staffs are not ready to release information needed for this project work. There were lots of information needed from the staffs of this institution to enhance the study which took them time to release or they did not release at all for security purposes, hence the scope was reduced.
1.7 Definition of Technical Terms
Peanut: this is the groundnut, goober, pindar or monkey nut, and taxonomically classified as Arachis hypogaea, is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics, being important to both small and large commercial producers.
Oil: Oil is any nonpolar chemical substance that is a viscous liquid at ambient temperatures and is both hydrophobic.
Peanut oil: Peanut oil referred to as groundnut oil or arachis oil, is vegetable-derived oil made from the edible seeds of the peanut plant.
Enterobacteriaceae: Enterobacteriaceae are Gram-negative, rod-shaped facultative anaerobes.
Antibiotic: a medicine (such as penicillin or its derivatives) that inhibits the growth of or destroys microorganisms.
Resistance: Resistance is a measure of the opposition to current flow in an electrical circuit.
Antioxidants: Antioxidants are molecules that fight free radicals in your body. Free radicals are compounds that can cause harm if their levels become too high in your body.
Activity: An activity is a phase, task, operation or other component within an activity group.
