Wyniki wyszukiwania - BazTech

1

High performance liquid chromatography based quantification of reserpine in Rauwolfia tetraphylla L. and enhanced production through precursor feeding

Rohela Gulab Khan, Bylla Prasad, Pendli Sreenu, Korra Rajender, Gandu Rajender, Reuben Christopher

Acta Chromatographica

|

2022

|

Vol. 34, no. 2

120--129

EN

Rauwolfia tetraphylla L., is an important medicinal plant in Apocynaceae family and is recognized as an alternative source to Rauwolfia serpentina L., in terms of anti-hypertensive alkaloid production i.e. reserpine. In view of this, the present study is conducted to estimate the reserpine content in different parts (leaf, stem and root) of field grown plants (2 years old), tissue cultured plantlets (R1) (two months old) and cell suspensions cultures (two months old with and without precursor feeding) of R. tetraphylla by using high performance liquid chromatography (HPLC) technique. Overall maximum content of reserpine (in %) was estimated from the root samples. Roots of field grown plants has recorded high percent of reserpine (0.39%) followed by roots of tissue cultured plantlets (0.35%) and root callus based cell suspension cultures (0.38 %) which was fed with precursor amino acid (100 mg/L of tryptophan). In control type of root callus based cell suspension cultures, reserpine content was quantified as 0.14%; by precursor feeding (100 mg/L of tryptophan) it was enhanced to 0.38%. In conclusion, the reserpine content (0.35 and 0.38%) produced by the roots of tissue cultured plantlets (R1) and 100 mg/L tryptophan fed root callus based cell suspensions was comparable to that of the reserpine content (0.39%) of root parts of field grown plants. The present study demonstrates the reserpine production by in vitro cell suspension cultures throughout the year without sacrificing the medicinal plants.

2

Tryptofan a autyzm

Gątarek Paulina, Rosiak Angelina, Kałużna-Czaplińska Joanna

Analityka : nauka i praktyka

|

2020

|

nr 2

56--58

PL

Zaburzone poziomy stężeń tryptofanu mogą pociągać za sobą nieprawidłowe formowanie innych związków, pełniących kluczowe role w funkcjonowaniu organizmu. Można domniemywać, że tym samym wpływają na stężenie serotoniny oraz melatoniny u dzieci autystycznych.

3

Production of indole acetic acid by endophytic Bacillus strains

Nabrdalik Małgorzata

Ecological Chemistry and Engineering. A

|

2018

|

Vol. 25, nr 1

93--105

EN

The objectives of this study were to isolate and characterize endophytic bacteria from sugar beet roots focusing on their ability to produce indole acetic acid (IAA). In order to isolate endophytic bacteria the sugar beet roots were used. To determine the amounts of IAA produced by endophytic Bacillus strains (B. amyloliquefaciens, B. megaterium and B. subtilis), a colorimetric technique was applied with Salkowski reagent. The isolates were grown in Laurin Broth medium supplemented with L-tryptophan over the concentration range of 100–10000 g/cm3 and incubated at 30 oC for 7 days. The highest concentration of IAA was recorded after 4 days of culturing in the supernatant obtained from the media containing 10000 g/cm3 of tryptophan. For the strain B. subtilis and B. megaterium the concentration of IAA marked in the post –culturing liquid amounted about 82.00 g/cm3, and for the B. amyloliquefaciens strain it amounted over 121.28 g/cm3. The strains Bacillus under study produced IAA in a different amount in the presence of L-tryptophan and in its absence.

PL

Celem pracy było wyizolowanie i scharakteryzowanie bakterii endofitycznych korzeni buraka cukrowego pod kątem ich zdolności do produkcji kwasu indolilooctowego (IAA). Materiał doświadczalny do izolacji bakterii endofitycznych stanowiły korzenie burak cukrowego. Ilość wytworzonego IAA przez endofityczne szczepy Bacillus (B. amyloliquefaciens, B. megaterium, B. subtilis) oznaczono metodą kolorymetryczną z odczynnikiem Salkowskiego. Szczepy hodowano w pożywce LB (Laurin Broth) suplementowanej L-tryptofanem w stężeniach 100–10000 g/cm3 i inkubowano w 30 oC przez 7 dni. Najwyższe stężenie IAA odnotowano po 4 dniach w hodowlach zawierających 10000 g/cm3 L-tryptofanu. Dla szczepu B. subtilis i B. megaterium stężenie IAA wynosiło około 82,00 g/cm3, a dla szczepu B. amyloliquefaciens 127,28 g/cm3. Badane szczepy Bacillus spp. wytwarzały IAA na różnym poziomie zarówno w obecności L-tryptofanu jak i przy jego braku.

4

Optymalizacja procesu rozdzielania tryptofanu i proliny w układzie faz odwróconych z wykorzystaniem mikrochromatografii cienkowarstwowej (micro-TLC) w warunkach kontrolowanej temperatury

Zarzycki P. K., Ślączka M. M.

Pomiary Automatyka Kontrola

|

2011

|

R. 57, nr 6

624-626

PL

Chromatografia cienkowarstwowa jest dogodną metodą do tzw. analiz przesiewowych (z ang. screen analysis) oraz szybkiego badania profili retencji z użyciem różnych faz ruchomych. Nasze badania dotyczą zastosowania termostatowanej mikrochromatografii cienkowarstwowej do optymalizacji procesu rozdzielania wybranych aminokwasów tryptofanu i proliny w układzie faz odwróconych (RP). Uzyskane dane retencyjne umożliwiły określenie optymalnych warunków rozdzielania przy zastosowaniu prostego parametru optymalizacji: maksymalnej wartości współczynnika rozdzielenia (αmax). Parametr ten był obliczany z dokładnością 2% stężenia binarnej fazy ruchomej w zakresie od 0 do 100%, na podstawie danych eksperymentalnych uzyskanych z rozdzielczością 20%. Wybrane kryterium optymalizacji umożliwia bezpośrednie przeniesienie uzyskanych wyników na systemy rozdzielania typu RP z użyciem kolumny zamiast płytek np. wysokosprawnej chromatografii kolumnowej (HPLC).

EN

Thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) are commonly used in separation, identification, purification and quantification of different analytes present in complex biological, environmental and pharmaceutical samples. Planar chromatography can be also applied to screen analysis and fast exploration of chromatographic retention profiles using different concentrations of mobile phases components. This method does not require expensive equipment, tedious and time-consuming sample pretreatments and, what is important, allows a parallel separation of many samples at the same time. The spots or bands sprayed onto the TLC plate can be easily detected under visible and UV light (usually 254nm, 366nm) or by post-chromatographic derivatization with visualization reagents, and then digitalized using office scanners. It should be noted that the great advantage of micro-planar chromatography compared to the regular sized TLC is low consumption of the eluents (usually less than 1 mL per analytical run) as well as short analysis time, due to mobile phase migration distance less than 50 mm. Under particular cases (high temperature and low viscosity eluents like acetone, dichloro-methane or n-hexane), non-forced eluent flow micro-chromatographic analysis can be completed within less than 5 minutes. This work is focused on optimization of separation process of two amino acids including tryptophan and proline (Fig. 1) under reversed-phase micro-chromatographic conditions. Particularly, selected amino acids were chromatographed on HPTLC RP-18W (wettable with water) 25 x 50 mm cutted plates using thermostated horizontal micro-chamber and unsaturated conditions (Fig. 2). The target components were sprayed on the start line (1Μg per lane) using a semi-automatic sampler (Linomat 5, Camag). The plates were developed with n-propanol: water binary mixtures as the mobile phases. Different concentrations of alcohol ranging from 0 to 100% (v/v) with steps of 20% were applied. The temperature of chromatographic separation was set at 40oC and chromatographic runs were completed within 10-30 minutes, depending on the water concentration in the mobile phase. The amino acids were visualized by dipping the plates in ninhydrin solution (prepared for concentration 0.3% in ethanol) followed by heating at 120°C for 10 minutes. Picture acquisition was performed using a Plustek OpticPro S12 scanner with an 8-bit per channel color deep mode, 300 DPI resolution, and saved as TIFF files. Retention data were derived from the plates via densitometric scans obtained with help of ImageJ freeware (http://rsb.info.nih.gov/ij). Using the raw retention data set (RF values, retardation factor), the chromatographic profiles of amino acids were calculated with step of 2% (Fig. 3A). Based on the curves observed and relationship RM = logk, where RM and k correspond to mobility and retention factors, respectively, a simple optimization criterion expressed as a separation factor (α) was calculated (Fig. 3B). Using this plot, the best separation conditions of target components were selected taking into account the maximum value of the separation factor (αmax). Due to the equal spot shape of amino acids investigated across the whole range of the mobile phases composition, such approach involving the α values allows fast optimization of separation in planar chromatography and direct application of selected conditions into column chromatographic systems based on e.g. high-performance liquid chromatography (HPLC). It should be noted that the advantages of retention data screening using micro-TLC are very low mobile phase consumption (at level of 300 ΜL per chromatographic run), short analysis time and effective detection of UV-Vis transparent substances using simple visualization reagent.

5

The effect of immobilization in the PVA films on the fluorescence and phosphorescence lifetime of indole and its derivatives

Kowalska-Baron A., Choudhary P., Montes D.

Biotechnology and Food Science

|

2011

|

Vol. 75, nr 2

3-14

EN

This work is devoted to study how immobilization in the PVA films affects the fluorescence and phosphorescence lifetime of indole and its derivatives. The obtained results indicated that immobilization of the studied indoles in the PVA matrix, which leads to the increased microrigidity of the environment around the indole moiety, results in the increase of singlet and triplet excited state lifetime of the studied compounds. Most probably, the enhancement of the rigidity of the environment near the chromophore reduces the rates of the non-radiative deactivation pathways, which leads to the increase of excited state lifetimes of the studied compounds.

6

Spectroscopic studies of naproxen and tryptophan immobilized in polyvinyl alcohol

Sabara D. M., Dunne J. S., Pedro A. Q. H., Trifunović J., Balogun I. I. O., Kotlicic O., Serrano A., Kertesz I.

Biotechnology and Food Science

|

2011

|

Vol. 75, nr 1

39-49

EN

Hydrogels are cross-linked hydrophilic polymer networks that find application in biomedical and pharmaceutical industries due to their unique properties. Polyvinyl alcohol is a synthetic polymer, potential biomaterial blended with various materials and compounds, that can provide new options for drug delivery systems. Determination of photochemical properties of naproxen and tryptophan immobilized in polyvinyl alcohol and two other media: water and cyclohexane was performed using UV-Vis absorption and fluorescence methods. The influences of the media used on the spectral properties of naproxen and tryptophan have been shown.

7

Tritium kinetic isotope effects on enzymatic decomposition of L-tryptophan

Boroda E., Kański R., Kańska M.

Nukleonika

|

2006

|

Vol. 51,suppl.2

17-19

EN

The tritium kinetic isotope effect on position 2 has been determined in the reaction of decomposition of L-tryptophan, L-Trp, catalyzed by enzyme TPase, (EC 4.1.99.1). The numerical values of isotope effects in the course of reaction were obtained by the competitive method using [1-14C]-L-tryptophan as internal radiometric standard.

8

Solvent Pre-Treated Wool Fabric Permanent Set and Physical Properties

Treigiené R., Musnickas J.

Fibres & Textiles in Eastern Europe

|

2003

|

Vol. 11, no. 1 (40)

37--40

EN

We present the results of an investigation which shows that the yellowing of wool fibre which occurs during light exposure and treatment with boiling water is reduced by pre-treatment of loom state wool fabric with perchloroethylene. The changes in light reflectance and the yellowing index of the treated wool fabric were found to correlate with the data of wool fibre strength, permanent set degree, solubility in urea-bisulphite solution, fluorescence emission and thermogravimetric analysis

PL

W artykule przedstawiono wyniki badań nad zmniejszeniem zażółcenia włókien wełnianych, spowodowanego naświetlaniem i obróbką w gorącej wodzie. Stwierdzono dodatnie oddziaływanie nadchloroetylenu na tkaniny wełniane surowe, otrzymane z krosna. Stwierdzono korelacje pomiędzy odbiciem światła i współczynnikiem zażółcenia obrabianych tkanin a wytrzymałością włókien wełnianych, stopniem trwałości stabilizacji, rozpuszczalnością w roztworze mocznika wodorosiarczynu, emisją fluoroscencyjną i wynikami analizy termograwimetrycznej.