EFFECTS OF DIFFERENT NITROGEN SOURCES ON THE ANTIFUNGAL ACTIVITIES OF ACTINOMYCETE ISOLATED FROM THE SOIL

ABSTRACT

Actinomyces sp. And Streptomyces sp. was isolated from the soil of Okwuta in Abia State. Physiological and biochemical analysis strongly suggested that the isolate belonged to the strains ofActinomycete .Nitrogen source is a critical component of cultivation medium and almost the useful tool for stimulation of the antifungal metabolites production. The aim of this study was to select the best nitrogen sources in medium for the production of antifungal compounds effective against Collectotrichum and Alternaria sp. Activity of the cultivation liquids on Alternairia and Collectotrichum isolates was tested in vitro using Agar well diffusion method. The results  indicate that maximum inhibition zone was reached in medium with soybean meal as nitrogen source with inhibition diameter 25.3mm for Alternaria sp.,15mm for Collectotrichum sp. in isolate 1( Actinomyces sp) and 17.5mm for Collectotrichum sp., 27.7mm for Collectotrichum sp in Isolate 2 (Streptomyces spp). Malt and urea showed the  least minimum  inhibition  zone for both tested fungi and isolates.

TABLE OF CONTENTS

Title page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgement ﾿ iv

Table of contents ﾿     v

List of tables ﾿     viii

Abstract ﾿   ﾿ ix

CHAPTER ONE 

1.0 Introduction ﾿ 1 

1.3 ﾿ Aim and objectives ﾿ 4

1.4 ﾿ Objectives      ﾿ 4

CHAPTER TWO

2.0    Literature Review ﾿ 4 

2.1    Taxanomy ﾿             8 

2.2    Bioactive Agents In Actinomycetes    ﾿ 10

2.2.1 Antibiotics ﾿       ﾿ 10

2.2.2 Antifungals ﾿       ﾿ 10 

2.3    Plant Growth Bioactive Molecules ﾿ 11

2.3.1 Indole Acetic Acid ﾿   ﾿ 11 

2.3.2 Hydrogen Cyanide ﾿ 12

2.4   Enzyme Production from Actinomycetes ﾿ 13 

2.5   Actinomycetes as Source of Agroactive Compounds ﾿ 15 

2.6   Actinomycetes As Biocontrol Tools ﾿ 17

2.6.1 Plant colonization and biocontrol ﾿ 18 

2.6.2 Actinomycetes as Biopesticide Agents ﾿ 19 

2.7   Optimization Of Actinomycetes ﾿ 21 

2.8   Colletotrichum ﾿ 22 

2.9   Alternaria ﾿ 23

CHAPTER THREE

3.0      ﾿ Materials and Methods ﾿ 25

3.1 ﾿ Sample Collection ﾿ 25

3.2 ﾿ Sterilization of Materials  ﾿ 25

3.3       Pre-treatment of Soil Samples ﾿ 25

3.4 ﾿ Media Used ﾿ 25

3.4.1 ﾿ Media Preparation ﾿                    25 ﾿

3.4.2    Test Organisms ﾿ 26

3.5 ﾿ Serial Dilution ﾿ 26

3.5.1 ﾿ Culturing ﾿ 26

3.5.2 ﾿ Identification ﾿ 27

3.5.3 ﾿ Sub-culturing ﾿ 27

3.5.4 ﾿ Gram Staining ﾿ 27

3.6 ﾿ Biochemical Test ﾿ 28

3.6.1 ﾿ Starch hydrolysis test ﾿ 28

3.6.2 ﾿ Hydrogen sulfide test. ﾿ 28

3.6.3    Gelatin hydrolysis ﾿ 29

3.6.4 ﾿ Catalase test ﾿ 29

3.6.5 ﾿ Oxidase test ﾿ 29

3.6.6 ﾿ Carbohydrate fermentation test ﾿ 30

3.7       Optimization of Different Nitrogen Source ﾿ 30

3.8      Crude Extraction ﾿ 31

3.9      In-Vitro Antimicrobial Test ﾿ 31

CHAPTER FOUR

4.0      Results ﾿ ﾿ ﾿ 32

CHAPTER FIVE

5.0   Discussion, Conclusion and Recommendation ﾿ 37

5.1   Discussion ﾿ 37

5.2   Conclusion ﾿ 40

5.3   Recommendation ﾿ ﾿ 40

References ﾿ 41 

Appendix ﾿ 50 

LIST OF TABLES

  Table                                        ﾿ Title  ﾿ Page

 1:    Shows the Morphology of isolated Organisms    ﾿ 33

2:    Shows the Biochemical Characterization of isolated organisms  ﾿ 34

3:  Shows the effects of different nitrogen sources on Actinomyces spp ﾿ 35

(isolate 1) and ﾿   their impact on Antimicrobial agent production  

measured by inhibition zones against Alternaria sp. And  Collectotrichum sp. 

By agar well diffusion method.

 4   Shows the Effects of Different Nitrogen Sources on Streptomyces spp.  ﾿ 36

(isolate 2) and Their Impacts on Antimicrobial Agent Production Measured By Inhibition Zones  ﾿      Against  Alternaria sp. and Collectotrichum sp. by Agar well diffusion method.