COMMERCIAL AND MEDICINAL VALUE OF ZIMBABWEAN SEED BEARING PLANTS M. Gundidza Harare Institute of Technology, Department of Pharmaceutical Technology,

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1 COMMERCIAL AND MEDICINAL VALUE OF ZIMBABWEAN SEED BEARING PLANTS M. Gundidza Harare Institute of Technology, Department of Pharmaceutical Technology, Harare, Zimbabwe E. Gundidza Chinhoyi University of Technology, Department of Production Engineering, Chinhoyi, Zimbabwe K. Erlwanger, Department of Physiology, University of the Witwatersrand, South Africa. Samie Amidou Unicersity of Venda, South Africa, Department of Microbiology, South Africa Michael Libala Magwa University of Fort Hare, Department of Botany, South Africa

2 INTRODUCTION The importance of plant seeds as raw materials in the food and drug industry is crucial. They contain a number of growth substances and reserve food supplies which play an important role in seed germination. Their reserve foods are stored mainly in the form of carbohydrates, fats and proteins (Copeland LO and McDonald MB, 2001). The mineral concentration in the seed oil is negligible as compared to other parts, with the exception of the hull. For example, the soybean contains an intact hull which accounts for the significant amount of mineral content.

3 INTRODUCTION There is a need for the investigation of plant seeds as a sustainable resource of raw materials in therapeutics and food and biofuel industries. Lipids can be classified as either simple, compound or derived. Simple lipids are esters of fatty acids and glycerol or other alcohols (e.g. fats and fatty oils), while compound lipids are esters of fatty acids with additional chemical groups (e.g. phospholipids). Derived lipids are synthesized from simple and compound fatty acids by hydrolysis (e.g. cholesterol).

4 INTRODUCTION Fats can be distinguished from oils based on their appearance at room temperature: Oils remain in a liquid state while fats solidify. A decaying plant is most likely to contain free fatty acids due to hydrolysis. The acid value is a useful indication of the amount of free fatty acid in oil.

5 INTRODUCTION Importance of phytoconstituents Fatty acids are important to human beings for the following reasons: Making substances which function like hormones responsible for the regulation of blood pressure, blood clotting, plasma lipid concentration & the immune system (Vicente, AR et.al, 2009). Fatty acids can either be divided into saturated, monounsaturated or polyunsaturated based on their chemical structure. Monounsaturated fatty acids have one double bond in its hydrocarbon chemical structure whereas polyunsaturated fatty acids have more than one (Vicente, AR et.al, 2009). Unsaturated fatty acids is most common in seeds with oleic (one double bond) and linoleic (two double bonds) acids. Fatty acids can be combined with glycerol and alcohols to yield different lipids like trihydroxy alcohol and glycerine.

6 INTRODUCTION Importance of phytoconstituents Omega 3 & Omega 6 are examples of polyunsaturated fatty acids. They are essential fatty acids because humans lack the enzymes necessary to produce these compounds (McCusker MM,Grant-Kels JM,2010). The two main fat precursors of these fatty acids are linoleic acid (18:2ω6) and α-linolenic acid (18:3ω3). They give rise to long chain fatty acids e.g. γ-linolenic acid, arachidonic acid (ω-6 fatty acids), docosahexaenoic acid and eicosapentaenoic acid (ω-3 fatty acids).

7 INTRODUCTION Importance of phytoconstituents Safflower, grape seed, poppy seed, sunflower, hemp, corn, wheat germ, cottonseed and the soybean are the main sources of Linoleic acid (omega 6). It is a structural precursor of stratum corneum, ceramides and its function is to maintain the integrity, maturation and differentiation of cells. Certain diseases like dermatitis can be treated by supplementation with Omega 6 because it alters the permeability of the stratum corneum. Omega 3 (α-linolenic acid) is contained in green leafy vegetables, flax seed, walnuts, soybean and canola oils.

8 INTRODUCTION Importance of phytoconstituents Cooking or processing of these foods results in the destruction of omega 3. The derivatives of omega 3 fatty acid serve as immune modulators which are responsible for inhibiting proinflammatory eicosanoids, cytokines (TNF-α, interferon-γ, and interleukin-12) and lipoxygenase. The ideal homeostatic cellular concentration of omega 3 and 6 should be 1:6 and a change could have negative implications on the immune system.

9 INTRODUCTION Importance of phytoconstituents The first fatty acid produced in lipogenesis in humans is palmitic acid, CH 3 [CH 2 ] 14.COOH, a straight chain fatty acid derived from Acetate + malonate. Coconut or palm trees are the main source, however it can be found in meat, cheese, butter & milk. In a recent study conducted on rodents, palmitic acid was shown to mediate hypothalamic insulin resistance (Benoit CS, Kemp CJ, Elias FC,et al. 2009). Sodium palmitate, a palmitic acid derivative, is used as a natural additive in organic medicinal products. Moderate consumption is advised, because increased consumption of palmitic acid may contribute to an increase risk of developing cardiovascular diseases due the increased amount of cholesterol that is produced (WHO, 2003).

10 INTRODUCTION Importance of phytoconstituents Stearic acid, a saturated long chain fatty acid, is also known as octadecanoic acid. Commercially it is obtained by formulating equal quantities of palmitic acids and small amounts of oleic acid (Encyclopedia Britannica, 2011). Apart from the use in cosmetics, soaps, shaving creams and dietary supplements it is very useful in the pharmaceutical industry. Calcium stearate and magnesium stearate are tablet lubricants while zinc stearate is used as a dusting powder. An emulsifying and suspending agent have been identified in the form of sodium stearate and aluminium stearate respectively.

11 Some Plant Seeds Studied AFZELIA QUANZENSIS ( MUKAMBA)

12 Some Plant Seeds Studied.. CASSIA ABBREVIATA (MURUMANYAMA)

13 Some Plant Seeds Studied.. GREWIA FLAVESCENS (MUBHUBHUNU)

14 Some Plant Seeds Studied.. BRUDELIA MOLLIS (HWENGWEDZA)

15 Some Plant Seeds Studied.. KIGELIA AFRICANA (MUBVEVE)

16 Some Plant Seeds Studied.. XIMENIA CAFFRA (NHENGENI)

17 OBJECTIVES Collection and identification of seed plants Extraction of the oils Fatty acid profiling Physicochemical analysis Identification of the appropriate use of the oil Formulation and commercialization of the product(s)

18 Materials and Methods One lipid molecule (triglyceride) is made up of three fatty acids and one glycerol molecule. Plant and animal derived lipids are mainly soluble in ether, chloroform, benzene and organic solvents (Copeland LO and McDonald MB, 2001). Thus; hexane is a suitable solvent to be used during the extraction process In search for commercial seed oils, seeds were collected, identified by botanists at the National Botanic Gardens, Harare, dried at 40 0 C in an oven, dehulled and pulverized in motor and pestle.

19 Materials and Methods.. The pulverized seeds were immersed in n-hexane for five days with occasional shaking to extract the oil. The process was repeated until no oil was coming out of the pulverized seeds. The n-hexane was driven off the extract by using a rotavapour to obtain the oil To identify the fatty acid content, samples of the fruit seeds oils were taken to ARC for identification. The percentage yield, colour and state at room temperature, acid value, iodine value and saponification values of the oils were recorded.

20 Materials and Methods.. The physicochemical characteristics to be studied. Colour of oil State at room Temperature % yield Iodine value Saponification value, Acid value

21 Materials and Methods.. Extraction Process Solvent removal

22 Materials and Methods Quantification of extracted oil

23 Materials and Methods Fatty acid profiling was done at Agricultural Research Council (ARC) in South Africa.

24 Results The results are expected to indicate category of use of the fatty acid such as: Medicinal use (Omega 3, 6, and 9 etc) Soap Making (oleic acid, stearic acid, palmitic acid etc) Cosmetic use etc) (oleic acid, stearic acid, palmitic acid

25 Products Sanitizer Anti-acne cream

26 Products Sanitizer Soap

27 Products Product collection Lipbalms

28 Training in Zambia Transfer of technology

29 Transfer of technology. Training in Zambia

30 Transfer of technology. Training in South Africa-Limpopo Province

31 Transfer of technology. Training in South Africa-Limpopo Province

32 Transfer of technology. Cream preparation

33 DISCUSSION Seed bearing plants can be a rich source of raw materials for the pharmaceutical, cosmetic, biofuel and biofertilizer industries. There is huge export market for some of the indigenous oils such as Ximenia caffra, Marula oil, Kigelia Africana oil, Adansonia digitata oil with a lot of potential for new oils that we are currently working on.

34 RECOMMENDATIONS The project needs to be supported financially in order to create wealth for the country, job creation and improvement of the livelihoods of the rural communities.