project honey as antimicrobial agent final full.pdf - University of ...

More documents

Recommendations

Info

AmpC β-lactamases, compared to ESBLs are able to hydrolyse third generation cephalosporins but are not inhibited by β-lactamase inhibitors such as clavulanic acid, sulbactam and tazobactam (Murray et al., 2007). The detection of the ESBL gene in the Enterobacteriaceae can be difficult if AmpC plasmids are present in the same isolate, as well as ESBL gene. To avoid this cefepime or cefpirome (AmpC- stable cephalosporins) can be used in combination with β-lactamases inhibitors such as clavulanate or boronic acid, even though this detection is not 100% perfect when using these combinations (Hawkey 2008). 1.2.2.6 Carbapenemases (class A, B, D) Carbapenems have been suggested as the most effective treatment for the most extended-spectrum-β-lactamases. However, increasing reports of carbapenemases enzymes that are able to hydrolyse oxyimino-cephalosporins, cephamycins and carbapenems makes treatment difficult (Murray et al., 2007). Carbapenemases belong to three molecular classes: A, B and D. Class A carbapenemases can hydrolyse imipenem but are inhibited by clavulanic acid. Most of this class has chromosomal genes, but some are plasmid-mediated, such as KPC-1 which is found mainly in K. pneumoniae. Class B such as IMP or VIM group are not inhibited by clavulanic acid (Murray et al., 2007). Recently Yong et al., (2009) was first to report a new subgroup case of class B of metallo β- lactamases called NDM-1 isolated from New Delhi, India. This mobile gene was detected on a plasmid and found mainly in K. pneumoniae. NDM-1 with 28 kDa can hydrolyse all β-lactams antibiotics except aztreonam and it represents a potential public health problem (Kumarasamy et al., 2010). Class D carbapenamases are mostly found in Acinetobacter baumannii. However, they can develop resistant to carbapenems if there is an alteration in a porin. 38
1.2.3 Emergence of ESBL: The production of the TEM and SHV β-lactamases in plasmid mediated resistance strains initiated many clinical problems after the introduction of ampicillin in the 1960s. In the early 1980s, third generation extended spectrum cephalosporins, such as cefotaxime and ceftazidime had been developed and offered reliable treatment for patients infected with Enterobacteriaceae. However, in the mid 1980s the first ESBL producing organisms (resistant to third generation cephalosporins) were isolated. Very rapidly mutations in amino acids in both TEM and SHV genes occurred, which spread specifically between Klebsiella species and some strains of E. coli. As a result in the emergence of the ESBL mutant, derivatives of these widely spread β- lactamases that were capable of hydrolysing third generation cephalosporins and monobactams appeared (Hawkey 2008). Both excessive use of antibiotics and environmental conditions were therefore consider to be main reasons for the emergence and spread of resistance. ESBL have also been reported in Enterobacter, Salmonella, Proteus, Citrobacter, Morganella morganii, Serratia marcescens, Shigella dysenteriae, Pseudomonas aeruginosa, Burkholderria cepacia and Acinetobacter baumannii (Moland et al., 2008). 1.2.4 Risk factors for ESBL: To determine the risk factors of ESBL producing organisms, several studies were conducted in different countries. It was found that ESBL-producing strains were associated with low patient outcome and crowded hospitals and were also linked to improper first line treatment (Amabile-Cuevas 2007). The risk factors for most ESBLs are excessive previous use of multiple ranges of antibiotics, including third 39
Page 1 and 2: Honey as an antimicrobial agent aga
Page 3 and 4: 1.2.3 Emergence of ESBL: 9 1.2.4 Ri
Page 5 and 6: 2.2.1 Honey sample collection: 51 2
Page 7 and 8: 2.5 Effect of honey on bacterial st
Page 9 and 10: viable count 3.4.2.1 Acinetobacter
Page 11 and 12: Declaration This work has not previ
Page 13 and 14: Acknowledgments I wish to express m
Page 15 and 16: Index of Tables Tables Title Page T
Page 17 and 18: Index of Tables (Continued) Tables
Page 19 and 20: Index of Figures Figure Title Page
Page 21 and 22: Index of Figures (Continued) Figure
Page 27 and 28: ESBL- Extended spectrum beta lactam
Page 29 and 30: TEM- Temoneira UTI- Urinary tract i
Page 31 and 32: Chapter 1 Introduction 31
Page 33 and 34: such as methicillin resistant Staph
Page 35 and 36: Beta-lactamases in this classificat
Page 37: cefotaxime faster than ceftazidime;
Page 41 and 42: Acinetobacter spp are widespread in
Page 43 and 44: many secretions of normal people an
Page 45 and 46: 1.3.4.1 The production of exopolysa
Page 47 and 48: 1.3.5 Emergence of Resistance: A.ba
Page 49 and 50: In the last few years resistant str
Page 51 and 52: More recently, a study was carried
Page 53 and 54: Gideonsen 2005), malignant ulcers (
Page 55 and 56: Nezeako & Hamdi, (2000) tested six
Page 57 and 58: In addition, honey contains several
Page 59 and 60: with the help of an enzyme (glucose
Page 61 and 62: (Wahdan 1998), and vanillic acid, c
Page 63 and 64: Table 1.2: Comparisons between pero
Page 65 and 66: Another study compared the effectiv
Page 67 and 68: of raw honey samples from Acacia, h
Page 69 and 70: 1.5 Aims and Objectives: The aim of
Page 71 and 72: The materials used throughout this
Page 73 and 74: Table 2.3: Chemicals and Reagents u
Page 75 and 76: Table 2.5: Equipment used in electr
Page 77 and 78: Fifty five clinical isolates belong
Page 79 and 80: 2.1 Characterization of test organi
Page 81 and 82: 2.2 Characterization of honey sampl
Page 83 and 84: transfered into a large square assa
Page 85 and 86: 2.2.3 Determination of pH: This met
Page 87 and 88: once the tubing opened at one end a
Page 89 and 90:
was re-suspended in 1 ml liquefied
Page 91 and 92:
difference between this absorbance
Page 93 and 94:
and Omani honey (B) with hydrogen p
Page 95 and 96:
2.3.1.2 Broth dilution method: 2.3.
Page 97 and 98:
2.4 Time Kill Curve Assay: 2.4.1 St
Page 99 and 100:
2.5.1.2 Preparation of cells in the
Page 101 and 102:
2.5.2.2 Preparation of cells for tr
Page 103 and 104:
Table 2.14: Reagents and buffers us
Page 105 and 106:
samples (Fig 2.3). Each sample was
Page 107 and 108:
tray was covered and wrapped in sar
Page 109 and 110:
Chapter 3 Results 109
Page 111 and 112:
Table 3.1a: Identification and anti
Page 113 and 114:
Table 3.2: Confirmation of identity
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
The diameter of the zones of inhibi
Page 121 and 122:
Table 3.7: Antibacterial activity o
Page 123 and 124:
with visual estimation. The colour
Page 125 and 126:
Figure 3.3: Image of pollen present
Page 127 and 128:
3.3 Determination of antibacterial
Page 129 and 130:
3.3.1.2 Broth dilution method: The
Page 131 and 132:
The MIC range of 30 Acinetobacter i
Page 133 and 134:
Mean MIC and MBC (%w/v) values of m
Page 135 and 136:
Table 3.15: Susceptibility of 15 En
Page 137 and 138:
3.3.2 Sensitivity of MDR and ESBLs
Page 139 and 140:
Table 3.18: Susceptibility of 11 Kl
Page 141 and 142:
Table 3.20: Susceptibility of 15 En
Page 143 and 144:
Table 3.22: Susceptibility of 8 Ser
Page 145 and 146:
3.4 Time Kill Curves One representa
Page 147 and 148:
Figure 3.6: The effect of manuka ho
Page 149 and 150:
3.4.2 Inhibition of test organisms
Page 151 and 152:
This data was done in triplicate Nu
Page 153 and 154:
This data was done in triplicate Fi
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Figure 3.15: The effect of manuka h
Page 163 and 164:
All isolates showed statistically s
Page 165 and 166:
Figure 3.16: Growth curve of Acinet
Page 167 and 168:
Figure 3.20: Growth curve of Citrob
Page 169 and 170:
(Table 3.26). The length of individ
Page 171 and 172:
Figure 3.24: SEM micrograph of untr
Page 173 and 174:
Figure 3.28: SEM micrographs of unt
Page 175 and 176:
C D Cell division Multiple septa in
Page 177 and 178:
Figure 3.31: SEM micrographs of Aci
Page 179 and 180:
Page 181 and 182:
3.5.2.3 SEM of Klebsiella Klebsiell
Page 183 and 184:
Page 185 and 186:
Figure 3.39: SEM micrographs of Kle
Page 187 and 188:
Figure 3.40: SEM micrographs of Kle
Page 189 and 190:
C D 189
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
3.5.2.5 SEM of Citrobacter For Citr
Page 197 and 198:
Figure 3.47: SEM micrographs of Cit
Page 199 and 200:
Figure 3.49: SEM micrographs of Cit
Page 201 and 202:
Page 203 and 204:
Table 3.26: Comparison of changes i
Page 205 and 206:
Figure 3.54: Transmission micrograp
Page 207 and 208:
Page 209 and 210:
3.5.2.2. TEM for E.coli: TEM images
Page 211 and 212:
Page 213 and 214:
Page 215 and 216:
Figure 3.62: 2-D protein electropho
Page 217 and 218:
“The therapeutic potential of unc
Page 219 and 220:
Non-peroxide honey shown to be effe
Page 221 and 222:
Sugars are the major content of hon
Page 223 and 224:
Acacia (thorn trees), Myrtacae euca
Page 225 and 226:
major wound pathogens, consistently
Page 227 and 228:
MIC % (w/v) Previous studies MIC %
Page 229 and 230:
Figure 4.3: Mean MIC and MBC (%w/v)
Page 231 and 232:
4.4 Inhibition of test organisms by
Page 233 and 234:
honey chemistry. Nevertheless, obse
Page 235 and 236:
In TEM, the cell membrane was inter
Page 237 and 238:
with more than (3-log10 reduction).
Page 239 and 240:
To date there is little research on
Page 241 and 242:
The effect of defensin peptide was
Page 243 and 244:
4.6 Further investigations: There i
Page 245 and 246:
Chapter 5 References 245
Page 247 and 248:
� Al-Jabri, A. A., Nzeako, B. C.,
Page 249 and 250:
� Bang, L. M., Buntting, C. and M
Page 251 and 252:
� Bou, G., Oliver, A. and Martine
Page 253 and 254:
� Cooper, R. (2005) The Antimicro
Page 255 and 256:
� Efem, S. E., Udoh, K. T. and Iw
Page 257 and 258:
� Greenwood, D., Finch, P., Davey
Page 259 and 260:
� Kagan, B.L., Ganz, T. and Lehre
Page 261 and 262:
esistant Staphylococcus aureus (CA-
Page 263 and 264:
� Murray, P. R., Baron, E. J., Jo
Page 265 and 266:
� Scholar, E. M. and Pratt, W. B.
Page 267 and 268:
� Subrahmanyam, M. (1998) A prosp
Page 269 and 270:
� Wadi, M., Al-Amin, H., Farouq,
show all

project honey as antimicrobial agent final full.pdf - University of ...

Create successful ePaper yourself

Delete template?

Save as template?