euro-biotechnology-genomics-congress-2018-tracks

6 / 19

Page 26
N o v e m b e r 2 6 - 2 7 , 2 0 1 8 | M a d r i d , S p a i n
&
&
BIOTECHNOLOGY
Euro Congress on
GENOMICS AND MOLECULAR BIOLOGY
International Conference on
CANCER SCIENCE AND THERAPY
Global Congress on
Joint Event on
OF EXCELLENCE
IN INTERNATIONAL
MEETINGS
YEARS
Euro Biotechnology 2018 & Genomics Congress 2018 & Cancer Congress 2018 Journal of RNA and Genomics | ISSN: 2591-7781 | Volume 14
Anirban Banerjee et al., J RNA Genomics 2018, Volume 14
INTRACELLULAR, BIOFILM-INHIBITORY
AND MEMBRANE DAMAGING ACTIVITIES
OF NIMBOLIDE ISOLATED FROM
AZADIRACHTA INDICA A. JUSS (MELIACEAE)
AGAINST METICILLIN-RESISTANT
STAPHYLOCOCCUS AUREUS
Anirban Banerjee, Prodipta Sarkar, Saurabh Acharyya
Amarendra Patra, Karthika Thankamani, Hemanta Koley
and Prasanta K Bag
University of Calcutta, India
Staphylococcus aureus is a leading aetiologic agent of nosocomial- and
community-acquired infectious diseases worldwide. S. aureus causes
several human diseases, ranging from minor skin and soft tissue infections
to more severe conditions such as toxic shock syndrome, glomerulonephri-
tis, pneumonia, meningitis, endocarditis, osteomyelitis and septicaemia. The
public health concern regarding staphylococcal infections is inflated by the
increasing occurrence of multidrug-resistant strains, e.g. multidrug- and
meticillin- resistant S. aureus (MDR MRSA). This study was designed to eval-
uate the intracellular bactericidal activity and in vitro membrane-damaging
and biofilm-inhibitory activities of nimbolide isolated from Azadirachta indi-
ca against MDR MRSA. In vitro antibacterial activity of nimbolide was deter-
mined by performing MIC, MBC and time-kill kinetic studies. It showed much
lower MIC (8 μg ml-1) and MBC (32 μg ml-1) values than other antibiotics.
Biofilm-inhibitory activities were determined by SEM. Cellular drug accumu-
lation and assessments of intracellular activities were performed using Vero
cell culture. SEM findings revealed that exposure to nimbolide at 1X MBC on
S. aureus resulted in the disintegration of the bacterial cell envelope, severe
bacterial membrane perturbation, significant membrane damage, bursting of
cells and cell lysis. The biofilm structure was disrupted, and the biofilm forma-
tion was greatly reduced in the presence of nimbolide as examined by SEM.
The level of accumulation of nimbolide in Vero cells incubated for 24 h is
relatively higher than that of ciprofloxacin and nalidixic acid. The viable num-
ber of intracellular S. aureus was decreased [reduction of ~2 log10 c.f.u. (mg
Vero cell protein)-1] in a time-dependent manner in the presence of nimbolide
(4 X MBC) that was comparable to that of tetracycline and nalidixic acid. The
significant intracellular, biofilm-inhibitory and bacterial membrane-damaging
activities of nimbolide demonstrated here suggested that it has potential as
an effective antibacterial agent for the treatment of severe infections caused
by MDR MRSA.
Anirban Banerjee has completed his PhD at the age of 29
years from Visva Bharati Santiniketan, India. He is now
Post-Doctoral fellow in Department of Biochemistry, Uni-
versity of Calcutta, India. He is engaged in research in mi-
crobiology and parasitology and has many publications
in reputed Journals.
BIOGRAPHY