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EFFECT OF NEEM KERNAL AQUEOUS EXTRACT (NKAE) IN TEA MOSQUITO BUG HELOPELTIS THEIVORA (WATERHOUSE, 1886) (HETEROPTERA: MIRIDAE)
No full textAqueous extract of neem seed kernel (NKAE) was tested in laboratory condition to evaluate its antifeedant, ovicidal, nymphl duration and hatching performance on tea mosquito bug (Helopeltis theivora).Different concentrations of NKAE used were 1,2,3,4and 5%. In F1 population NKAE was significantly superior in antifeedant activity, hatching percentage ,oviposition period and nymphal duration @ 5% (248.2), (50%) , (8days) (5 day in 4th inster). The number of eggs laid by female was significantly less in 5% (23.33 Nos.) compared to other treatments
Influence of Physiochemical Factors on Size of Gold Nanoparticles Synthesised Using Leaf Extract of Syzygium Cumini
No full textSyzygium cumini is well known for its medicinal properties. This plant has shown potential for gold nanoparticles (GNP) synthesis. In the present study, we have varied physiochemical factors (metal ion, leaf extract ratio and incubation temperature) to see the influence on GNP size. GNPs of 13 to 70 nm size were synthesized by varying these parameters. The NPs thus synthesized through greener route and capped by medicinally important constituents can be very useful for applications in which products come in direct human contact
Synthesis and anti-angiogenic activity of benzothiazole, benzimidazole containing phthalimide derivatives
No full textBenzothiazole and benzimidazole containing phthalimide derivatives (NK037, NK041, NK042, NK0139A
and NK0148) have been synthesized and their anti-angiogenic activity was evaluated using ex vivo egg
yolk angiogenesis model. A comparative study with pure thalidomide (NKTA) has also been performed to
describe the efficacy of these derivatives in blocking angiogenesis. NK037, NK041 and NK042 were
equally potent in blocking egg yolk angiogenesis and the anti-angiogenesis effect was higher than NKTA
suggesting the efficacy of these three derivatives in blocking angiogenesis when compare to control.
Other two derivatives NK0139A and NK0148 showed effect less than NKTA and stronger than control
in ex vivo angiogenesis
ANALYTICAL METHOD FOR DETERMINATION OF ORGANOCHLORINE PESTICIDES IN TEA BREWS USING SINGLE-DROP MICROEXTRACTION WITH GC-ECD
No full textThe single drop microextraction method was developed for the determination of ten
organochlorine pesticides in tea brews using gas chromatograph-electron capture detector.
The optimized parameters for effective extraction required a 2 μL drop of n-hexane at the
tip of a microsyringe immersed in 5 mL of a diluted tea brew sample for 25 min and stirred
at 600 rpm. The limit of detection in the range of 0.01 to 0.025 μg/L, with relative standard
deviation of repeatability and reproducibility, was in the range of 1–10 and 8–24%. The relationship
of the measured signal was a linear function (>0.9863) of concentration and the
recovery method ranged from 92–116%. The single drop microextraction method showed the
advantage of being easy to operate, low consumption of organic solvent, and high extraction
efficiency
A New Method For Rapid Detection Of Total Colour (TC), Theaflavins (TF), Thearubigins (TR) and Brightness (TB) In Orthodox Teas
No full textTheaflavins (TF) and thearubigins (TR) are the
important chemical compounds, which contribute to the colour
and brightness of tea liquor. Estimation of TF and TR in black
tea is generally done using a spectrophotometer. But, the
analysis technique undergoes rigorous time consuming effort for
sample preparation; also the operation of costly
spectrophotometer requires expert manpower. To overcome
above problems an electronic vision system (E-Vision system)
based on image processing has been developed, which is faster,
low cost, repeatable and can estimate the amount of Total
Colour (TC), Brightness (TB), Theaflavins (TF) and TF/TR
ratio for orthodox tea liquors. This paper describes the newly
developed E-Vision system, experimental methods using
orthodox black tea sample, data analysis algorithms and finally,
the performance of the E-Vision system as compared to the
results of traditional spectrophotometer. The data analysis is
done using Principal Component Analysis (PCA) and Multiple
Linear Regression (MLR). A correlation has been established
between colour of tea liquor images and TC, TB, TR and TF/TR
ratio
Effect of decaffeination conditions on quality parameters of Kangra orthodox black tea
No full textEffect of extraction temperature and pressure on the removal of caffeine from Kangra orthodox black tea
using supercritical carbon dioxide was investigated. Maximum caffeine as well as volatile flavor components
was extracted at 35 °C/170 bar using 60 g/min flow rate for 90 min extraction in dynamic mode. Satisfactory
decaffeination and quality retention were achieved at extraction at 60 °C/90 bar. The quality of extracts
reduced at higher extraction temperature and pressure combinations. Maximum amounts of theaflavins
(88.88%), thearubigins (81.18%) and catechins (73.53%) were retained at these extraction conditions. Volatile
components in original (caffeinated) and decaffeinated black teas were isolated by simultaneous distillation
extraction (SDE), and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry
(GC–MS). 2-Hexenal, 3-hexenol, phenylacetaldehyde, cis-linalool oxide, linalool, trans-geraniol, nerolidol,
methyl salicylate, α- and β-ionones decreased in decaffeinated black teas compared to untreated control.
β-ionone (1.77%), trans-linalool oxide (5.36%), linalool (7.84%), trans-geraniol (4.32%) and methyl salicylate
(1.90%) were retained in satisfactory amount in decaffeination at 60 °C/90 bar. Application of aroma extract
dilution analysis revealed 11 odor active compounds with flavor dilution (FD) factor ranging from 8 to 512
and odor quality investigated by GC-FID, GC–MS. Some unknown compounds quantitatively reduced or
disappeared during decaffeination process. Although there was considerable loss of theaflavins and
thearubigins as well as volatile flavor components, SFE extraction at 60 °C/90 bar for 90 min appears as
the method suitable for selective removal of caffeine from the Kangra orthodox black tea
Efficient synthesis of hydroxystyrenes via biocatalytic decarboxylation/deacetylation of substituted cinnamic acids by newly isolated Pantoea agglomerans strains
No full textAbstract
BACKGROUND: Decarboxylation of substituted cinnamic acids is a predominantly followed pathway for obtaining
hydroxystyrenes – one of the most extensively explored bioactive compounds in the food and flavor industry (e.g. FEMA
GRAS approved 4-vinylguaiacol). For this, mild and green strategies providing good yields with high product selectivity are
needed.
RESULTS:Twonewly isolated bacterial strains, i.e. Pantoea agglomerans KJLPB4 and P. agglomerans KJPB2, are reported for mild
and effective decarboxylation of substituted cinnamic acids into corresponding hydroxystyrenes. Key operational parameters
for the process, such as incubation temperature, incubation time, substrate concentration and effect of co-solvent, were
optimized using ferulic acid as a model substrate. With strain KJLPB4, 1.51 g L−1 4-vinyl guaiacol (98% yield) was selectively
obtained from 2 g L−1 ferulic acid at 28 ◦C after 48 h incubation. However, KJPB2 provided vanillic acid in 85% yield after
72 h following the oxidative decarboxylation pathway. In addition, KJLPB4 was effectively exploited for the deacetylation of
acetylated α-phenylcinnamic acids, providing corresponding compounds in 65–95% yields.
CONCLUSION: Two newly isolated microbial strains are reported for the mild and selective decarboxylation of substituted
cinnamic acids into hydroxystyrenes. Preparative-scale synthesis of vinyl guaiacol and utilization of renewable feedstock
(ferulic acid extracted from maize bran) have been demonstrated to enhance the practical utility of the process
Estimation of Aroma Determining Compounds of Kangra Valley Tea by Electronic Nose System
No full textAroma is a major factor for quality evaluation of finished tea.Professional tea taster's distiguish the aroma of finished tea and decide the valuation of tea. Since tea taster's being humans their evaluations could be subjective.Instruments like spectrophotometer, high-performance liquid chromatography(HPLC)and gas liquid chromatography(GLC)measure the chemical/volatile compounds polyphenols,catechins and flavour profile of tea[b]. But these instruments are costly, time consuming, take long time to prepare the sample and also needs expert manpower to operate. Besides Electronic Nose (E-Nose)is also used by different tea factories to supplement the work of a tea taster for predicting the tea taster like score of finished tea. E-Nose can give tea taster like score within one and and half minute and easy of operate. This paper describes the estimation of tea compounds responsible for tea aroma by E-Nose
Application of betaine improves solution uptake and in vitro shoot multiplication in tea
No full textThe application of betaine, a quaternary ammonium
compound influenced the micropropagation in two
commercially important UPASI (U-9 and U-10) cultivars
of tea. Growth and multiplication of shoots of both the
cultivars was enhanced significantly in the presence of
125–1,000 mg l-1 betainewith best response at 1,000 mg l-1
betaine. The shoots turned brown and died within 15 days
when 1,500 mg l-1 betaine was applied. The study showed
faster water/nutrient uptake in the presence of betaine.Higher
assimilation of carbon and nitrogen in the presence of betaine
was also indicated in biochemical analyses. Thus, a decrease
in carbohydrates coupled with an increase in nitrate reductase
activity was recorded. Moreover, faster differentiation of
vascular elements and shoot thickness was observed in the
shoots of U-9 and U-10 growing on medium containing
1,000 mg l-1 betaine. Nutrient uptake, assimilation and
growth were significantly higher in U-10 as compared to U-9
shoots