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In vitro cytotoxicity, antimicrobial, and metal-chelating activity of triterpene saponins from tea seed grown in Kangra valley, India
No full textThis study was undertaken to isolate and
characterize saponins from seeds of Camellia sinensis.
Four triterpene saponins S1, S2, S3, and S4 were isolated by
chromatography on silica (60–120 mesh), followed by
purification on Sep-Pak C-18 columns. The chemical
structures (S1–S4) were elucidated on the basis of 1-D and
2-D NMR. All the saponins show broad-spectrum antifungal
activity against Candida albicans, Issatchenkia
orientalis, Aspergillus flavus, A. niger, A. ochraceous, A.
parasiticus, A. sydowii, and Trichophyton rubrum. The
most susceptible test fungus was T. rubrum inhibited at a
minimum inhibitory concentration of 31.25 lg/ml by all
the four saponins. Cytotoxicity of these saponins was
evaluated by methyl thiazole tetrazolium and sulfo-rhodamine
B assays. The saponins when tested against five
human cancer cells lines, viz., OVCAR-5 (ovarian carcinoma
cells), MCF-7 (human breast adenocarcinoma cells),
PC-3 (human prostate cancer cells), Colo-205 (colorectal
adenocarcinoma cells), and HL-60 (human promyelocytic
leukemia cells) showed high cytotoxicity activity (99 %)
by S1 and S2 on PC-3 cells at concentration of 100 lg/ml.
Similarly, when these saponins were tested against human
PBMCs by lymphocytes proliferation assay, none showed
significant activity. S3 (IC50 = 1.72 mg/ml) showed high
metal-chelating activity at a concentration of 20 mg/ml
Zephgrabetaine: A New Betaine-type Amaryllidaceae Alkaloid from Zephyranthes grandiflora
No full textZephgrabetaine (1), a new betaine type Amaryllidaceae alkaloid, along with seven known alkaloids, lycorine, galanthine, lycoramine, hamayne,
haemanthamine, tortuosine, and ungeremine were isolated from the bulbs of Zephyranthes grandiflora and their structures elucidated by spectroscopic data
analysis. The isolated alkaloids were tested for in vitro cytotoxic activities against two cell lines, C-6 (rat glioma cells) and CHO-K1 (Chinese hamster ovary
cells). A dose dependent cytotoxic effect was exhibited by all the alkaloids on these two cancer cell lines with prominent activity of lycorine and
haemanthamine
Induction and morpho-chemical characterization of Stevia rebaudiana colchiploids
No full textA study was conducted to produce higher biomass-yielding stevia Stevia rebaudiana (Bertoni) with larger leaf size
and high glycoside content. To improve leaf yield and sweet glycoside content found in the leaves of the plant, polyploidy
was induced by treating the seeds with colchicine. Treatment of seeds with 0.2% colchicine and above (up to 0.6%)
reduced the survival rate of stevia young seedlings to below 50%. Maximum number of polyploids (tetraploids) were
obtained with 0.6% colchicine treatment for 24 hr; mixoploidy was observed at 0.2% colchicine treatment for 6 hr. It
however needs further experimentation for more precise information. The nuclear DNA content (2C-value of diploid
Stevia rebaudiana variety Madhuguna) was estimated by flow-cytometry (FCM) to be 2.72pg. Polyploids C7-3-4, C7-3-
5, C9-1-1 and C9-4-3 could be distinguished from diploid control plants as they had double the DNA content, suggesting
autotetraploidy. Chromosome count in root-tip cells of polyploids (2n=44) confirmed their tetraploid status as compared
with the control (2n=22). The autotetraploids in stevia had significantly increased leaf size, thickness and chlorophyll
content and reduced internode length. Tetraploid stevia genotypes are important germplasm for further improvement of
stevia biomass and glycoside content
Synthesis and SAR investigation of natural phenylpropenederived methoxylated cinnamaldehydes and their novel Schiff bases as potent antimicrobial and antioxidant agents
No full textA series of cinnamyl compounds were synthesized
from abundantly available methoxylated phenylpropenes
and evaluated for their antimicrobial activity by the
broth microdilution method against fourteen opportunistic
bacterial and fungal human pathogens. Structure–activity
relationship studies indicated that methylenedioxy cinnamaldehyde
exhibited promising broad-spectrum activity
against the tested microorganisms and hence was used as a
lead structure to synthesize novel Schiff bases/heterocyclic
compounds (23–33) under microwave irradiation. Out of
these, thiazole-based Schiff bases have shown promising
antibacterial activity against B. subtilis (26; MIC 0.12 mM),
M. luteus (27; MIC 0.20 mM), and S. aureus (27; MIC
0.20 mM). Also, the compounds 23–33 were investigated for
in vitro antioxidant activity using DPPH• assay where
compound 28 showed a maximum of 80.71 % inhibition
Overexpression of CsANR Increased Flavan-3-ols and Decreased Anthocyanins in Transgenic Tobacco
No full textplants and synthesized by a common biosynthetic
pathway. Anthocyanin reductase (ANR) represents branching-
point enzyme of this pathway converting anthocyanidins
to flavan-3-ols. Since tea contains highest amount of flavonoids,
a cDNA encoding anthocyanin reductase from tea
(CsANR) was overexpressed in transgenic tobacco to check
the influence on anthocyanin and flavan-3-ols. The transgenic
tobacco was confirmed by genomic PCR and expression
of transgene was analyzed through semiquantitative
PCR. Interestingly flowers of transgenic tobacco were light
pink/white in color instead of dark pink in wild tobacco,
documenting the decrease in anthocyanins content. Upon
measurement, flower anthocyanin content was found to be
lesser. While flavan-3-ols (epicatechin and epigallocatechin)
contents were increased in leaf tissue of transgenic lines. The
expressions of other endogenous flavonoid biosynthetic
pathway genes in different floral parts (sepal, petal, stamen,
and carpel) of CsANR overexpressing tobacco as well as wild
tobacco were analyzed. The transcript levels of PAL and CHI
genes were downregulated, while transcript levels of F3H,
FLS, CHS, ANR1, and ANR2 genes were upregulated in all
floral parts of CsANR transgenic plants compared to wild
tobacco. The expressions of DFR and ANS genes were also
spatially modulated in different floral parts due to overexpression
of CsANR. Thus, CsANR overexpression increased
flavan-3-ols and decreased anthocyanin content by modulating
the expressions of various flavonoid biosynthetic
pathway genes in flower of tobacco. These changes might be
responsible for the observed pollen tube in the pollens of
CsANR overexpressing transgenic tobacco when they were
still in the anther before pollination
Comparative Analysis of DNA Methylation Polymorphism in Drought Sensitive (HPKC2) and Tolerant (HPK4) Genotypes of Horse Gram (Macrotyloma uniflorum)
No full textDNA methylation is known as an epigenetic modification that affects
gene expression in plants. Variation in CpG methylation behavior was studied in
two natural horse gram (Macrotyloma uniflorum [Lam.] Verdc.) genotypes, HPKC2
(drought-sensitive) and HPK4 (drought-tolerant). The methylation pattern in both
genotypes was studied through methylation-sensitive amplified polymorphism. The
results revealed that methylation was higher in HPKC2 (10.1%) than in HPK4
(8.6%). Sequencing demonstrated sequence homology with the DRE binding factor
(cbf1), the POZ/BTB protein, and the Ty1-copia retrotransposon among some of the
polymorphic fragments showing alteration in methylation behavior. Differences in
DNA methylation patterns could explain the differential drought tolerance and the
epigenetic signature of these two horse gram genotypes
Feasibility of fern Thelypteris dentata for revegetation of coal fly ash landfills
No full text(FA) landfills. In this context, the impact of metal accumulation on malondialdehyde (MDA), cysteine and
non-protein thiols (NPSH) contents was determined in T. dentata grown in FA amended with garden soil (GS)
in different ratio at 30 days and 45 days after treatment. The experimental results revealed that this fern species
possesses internal defense mechanism against toxicity of heavy metals of FA. There was a significant increase
(P≤0.01) of MDA, cysteine and NPSH observed in the below ground (i.e. roots including rhizome) as well as
above ground part (fronds) of T. dentata grown in 100% FA as compared to the plant species grown in 100%
GS. The results showed a high tolerance potential of this fern to endure oxidative stress bymetabolic adaptations
and showing feasibility of using T. dentata in the revegetation/stabilization of FA landfills
In vitro seed germination of economically important edible bamboo Dendrocalamus membranaceus Munro
No full textnot cop
Effect of organic manure and plant spacing on biomass and quality of Mentha piperita L. in Himalaya in India
No full textMentha piperita L. (peppermint) is one of the economically important aromatic–medicinal herbs in India. Cultivation
of M. piperita has so far not been attempted under sub-temperate agro-climatic conditions in the mid-hill of Himalaya.
A study on rationalization of level of farmyard manure (FYM) and plant spacing for M. piperita crop was conducted
during 2007 and 2008 at IHBT (CSIR), Palampur. The treatments consisted of four levels of FYM (0, 15, 30,
45 t/ha), three plant spacing (25 4.х 15, 40 4. х 15 and 50 4.х 15 cm2). Crop yield significantly increased with the level
of FYM and was significantly higher at 45 t/ha of FYM. The oil content in the crop ranged from 0.2% to 0.3%; however,
it was not affected by FYM application. Menthone content significantly increased with application of FYM and
was significantly higher at 45 t/ha of FYM, whereas content of menthyl acetate, neo-menthol and menthofuran significantly
decreased with application of FYM. The crop yield, oil content and composition of the oil were not affected
by variation in plant spacing. However, planting of M. piperita at 50 4.х 15 cm2 spacing and application of FYM at
45 t/ha was found to be favorable for biomass production and content of menthone
A method to overcome the waxy surface, cell wall thickening and polyphenol induced necrosis at wound sites - the major deterrents to Agrobacterium mediated transformation of bamboo, a woody monocot
No full textThe method is the first successful report of Agrobacterium
mediated genetic transformation of the commercially
important bamboo, Dendrocalamus hamiltonii. It
shows how the resistance provided by the somatic embryos
of this woody monocot can be overcome using a simple and
effective method. The method thus standardized can be also
used for the genetic transformation of other important
bamboos. Identification of the factors responsible for the
resistance of the somatic embryos to Agrobacterium infection
was an absolute requirement for devising a successful
method. Necrosis due to polyphenol oxidation, lack of differentiation
due to cell wall thickening at wound sites, waxy
surfaces of somatic embryos with anti-microbial properties
were found to prevent Agrobacterium attachment and infection.
Therefore, the somatic embryos were transformed with
fresh overnight grown Agrobacterium culture containing
500 mg/l polyvinylpyrrolidone (PVP) and 0.01 % Tween-
20 as surfactant followed by co-cultivation on Murashige
and Skoog (MS) medium containing the vir gene inducer
acetosyringone (100 μM) and 1 mg/l 6-Benzylaminopurine
BAP for 2 days. Persistent GUS expression and strong
positive signals in PCR, slot blot and Southern hybridization
confirmed successful genetic transformation