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This dissertation consists of two parts; “Part A” and “Part B”. The “Part A” consists of
phytochemical studies on three indigenous medicinal plants; Berberis brevissima Jafri,
Berberis parkeriana Schneid and Berberis royleana Ahrendt. The selected species of
Berberis have been investigated for the first time for their phytochemical constituents.
Three new (tirahamine (65), 13-nitrotirahamine (67) and peshawarine (68)) and eighteen
known compounds (berberine (69), dehydrocheilanthifoline (70), jatrorrhizine (71),
berberrubine (72), 8-oxoberberine (73), columbamine (74), palmatine (75), glutamic acid
(76), glutamic acid, methyl ester (77), di-glutamic acid (78), di-glutamic acid, methyl
ester (79), di-glutamic acid, di-methyl ester (80), docosanoic acid (81), 23a-
homostigmast-5-en-3ß-ol (82), β-sitosterol-3-O-β-D-glucopyranoside (83), nonacosane-
10-ol (84), palmitic acid (85) and linoleic acid (86)) have been isolated for the first time
from these selected species.
The three new bisbenzylisoquinoline alkaloids (tirahamine, 13-nitrotirahamine and
peshawarine) have been isolated from B. brevissima. The spectral studies of the two of
the compounds tirahamine and 13-nitrotirahamine were performed at different
temperature using different solvents. Acetylation and nitration of tirahamine (65) have
also been performed. In this part (Part A) we have described the isolation and structural
elucidation of the three new and eighteen reported compounds. The structural
characterization of the compounds have been achieved by using UV-Vis, IR, EI-MS,
ESI-MS, 1 H NMR,
13
C NMR, DEPTq, DEPT-90, DEPT-135, HMBC, HSQC, COSY,
NOESY and NOE techniques.
xiIn the
“Part B” of
the dissertation
anticancer,
antidiabetic,
antimicrobial,
antitrypanosomal and nematicidal activities of the fractions and the compounds isolated
from B. brevissima, B. parkeriana and B. royleana have been discussed.
The anticancer activities were performed against six cancer cell lines i.e. L1210 (Murine
lyphocytic leukemia), Colon 38 (Murine colon adrenocarcinoma), CFU-GM (Murine
granulocyte macrophage colony forming unit), H-116 (Human colon adrenocarcinoma),
H-125 (Human lung adrenocarcinoma) and CEM (Humane leukemic lymphoid).
Berberine (69) and jatrorrhizine (71) showed significant activity and selectivity against
L1210 and Colon 38 cell lines while palmatine (75) was inactive.
The antidiabetic activities were performed against Protein Tyrosine Phosphatase 1B (PTP
1B) which is a negative insulin regulator. Amongst the tested compounds, 8-oxob-
berberine (73) was significantly active and showed 29 % of the control. The other
isolated compounds i.e berberine (69) (35 %), dehydrocheilanthifoline (70) (38 %),
columbamine (74) (33 %) and jatrorrhizine (71) (36 %) also showed good activity while
glutamic acid (76) (78 %) was inactive.
Antimicrobial activities were carried out against four microbial strains i.e Mycobacterium
marinum, sporadic methicillin resistant Staphylococcus aureus (SMRSA), endemic
methicillin resistant Staphylococcus aureus (EMRSA) and Escherichia coli while
antitrypanosomal against Trypanosoma brucei which is a protozoa belonging to the genus
Trypanosoma, causing sleeping sickness. Tsetse fly is responsible for the transferring of
this parasitic protozoa from infected human and animals. The Berberis brevissima roots
xiifraction C (BBR-C) showed good activity against M. marinum (2.4 % of DMSO (D)
control), high activity against SMRSA (0.2 % of D control) and EMRSA (0.2 of % D
control) while against E. coli it was inactive. Berberine (69) showed good selectivity and
activity against SMRSA and EMRSA (1.1 and 0.5 % of D control).
Some of the fractions and compounds have also been tested for % mortality of stage two
juvenile of root knot nematodes i.e Meloidogyne javanica. Amongst the various fractions,
the Berberis brevissima roots fraction A (BBR-A) exhibited the highest mortality (62.22
%) followed by Berberis parkeriana roots fraction C (BPR-C) 57.22 % and BBR-C
(54.00 %). Berberine (69) showed the highest nematicidal potential at 97.3 % of the
standard (carbofuran) at the highest conc. (300 μg ml -1 ). Jatrorrhizine (71) ranked second
and exhibited 59.50 % mortality followed by berberrubine (72) (49.17 %).
Dehydrocheilnthifoline (70) was the least effective, nevertheless, showed good mortality
at the highest conc. |
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