THE EFFECTS OF FLAVOUR ENHANCERS ON NEUROBEHAVIOUR AND SOME BIOCHEMICAL PARAMETERS IN RATS

ABSTRACT

The study investigated the potentials of oral administration of some flavour enhancers, specifically monosodium glutamate MSG and fermented castor seed oil ogiri, in altering some biochemical parameters and neurobehavioral changes in rats Forty 40 male albino rats of mean weight 11654325g were randomly assigned into five groups AE of eight 8 rats each Rats in group A received 3g glutamate, group B was fed 3g Ajinomoto, group C received 6g Ajinomoto, group D was fed 3g ogiri Each of the doses was thoroughly mixed with 500g standard feed, while group E control was fed 500g standard feed All animals had free access to food and water ad libitum for a period of 4 weeks Monosodium glutamate at a dose of 6g/500g feed significantly Plt;005 increased aspartate aminotransferase activity by 2437 3g Ajinomoto, 6g Ajinomoto and 3g ogiri doses significantly elevated alanine aminotransferase activity by 4312 plt;005, 5862 plt;0001 and 4482 plt;005 respectively Alkaline phosphatase activity also increased in all the groups by 7963 plt;0001, 7383 plt;005, 106 plt;00001 and 7450 plt;005 MSG potentiated body weight, food and water intakes of rats when compared with the control The concentration of triglyceride significantly plt;00001 increased in rats treated with glutamate, while nominal increase was observed in rats fed Ajinomoto and ogiri In addition, these flavour enhancers did not affect cholesterol, although slight decrease in HDLcholesterol was obtained Ogiri consumption induced hyperglycemia by significantly plt;00001 elevated glucose concentration by 4493 in rats Rats fed 6g Ajinomoto showed a significantly plt;005 increased total protein concentration by 1004 Flavour enhancers markedly plt;00001 altered the neurobehavioral performance in rats The alteration manifested as less time spent in the open arm during the elevated plus maze EPM test The results emanating from this study suggest that flavour enhancers might have some deleterious effects on some organs, including the bone, as manifested by increased alkaline phosphatase activity, and altered neurobehavioral performance of rats Also, oral consumption of ogiri may have affected glucose utilization

TABLE OF CONTENT

Title pagei

Certificationii

Approval pageiii

Dedication iv

Acknowledgmentv

Table of contentvi

List of tablesx

List of figurexi

Abstractxii

Chapter One

Introduction1

11 Flavour enhancers1

12 Rationale for the study5

13 Aim of the study6

14 Objectives6

Chapter Two

Literature review7

21 Monosodium glutamate7

22 Glutamate metabolism in the body9

23 Glutamate: an amino acid acting as an excitatory neurotransmitter13

24 The role of glutamate in neurobehavioral alteration and neurological disorders19

241 Anxiety disorders21

242 Animal models of anxiety The elevated plus maze23

243 Parkinsons disease25

244 Clinical characteristics of Parkinsons disease26

245 Glutamatergic animal models of schizophrenia28

25 Medicinal uses of Ricinus communis Castor32

Chapter Three

Materials and methods36

31 Materials36

32 Preparation of ogiri36

33 Animals37

34 Experimental design37

35 Blood collection38

36 Biochemical assays38

361 Determination of plasma glucose38

362 Determination of total cholesterol39

363 Determination of triglyceride39

364 Determination of high density lipoprotein40

365 Determination of aspartate amino transferase AST40

366 Determination of alanine amino transferase ALT41

367 Determination of alkaline Phosphatase ALP41

368 Determination of total protein41

37 Behavioral test42

38 Statistical analysis43

Chapter Four

Results44

41 Body weight44

42 Food and water intakes44

43 Liver enzyme activities45

431 Aspartate aminotransferase AST45

432 Alanine aminotransferase ALT46

433 Alkaline phosphatase ALP46

44 Lipid profile46

441 Triglyceride46

442 Total cholesterol47

443 High density lipoprotein47

45 Blood glucose48

46 Total protein48

47 Behavioral Test48

Chapter Five

Discussion58

Conclusion67

References68

Appendix90