Polyphenolic Compounds from Flowers of Hibiscus rosa-sinensis Linn. and their Inhibitory Effect on Alkaline Phosphatase Enzyme Activity in vitro

2011 ◽  
Vol 66 ◽  
pp. 0453 ◽  
Author(s):  
J. Y. Salib ◽  
E. N. Daniel ◽  
M. S. Hifnawy ◽  
S. M. Azzam ◽  
I. B. Shaheed ◽  
...  
2011 ◽  
Vol 66 (9-10) ◽  
pp. 453-459 ◽  
Author(s):  
Josline Y. Salib ◽  
Enas N. Daniel ◽  
Mohamed S. Hifnawy ◽  
Shadia M. Azzam ◽  
Iman B. Shaheed ◽  
...  

Graded concentrations (0.1 - 100 mg/mL reaction mixture) of the methanolic extract of the flowers of Hibiscus rosa-sinensis Linn., its water-soluble fraction as well as compounds isolated from this fraction were tested for their inhibitory effect on alkaline phosphatase enzyme activity in vitro. Both the methanolic extract and its water-soluble fraction showed significant inhibitory effects on the enzyme activity in vitro. On screening the activity of the compounds isolated from the water-soluble fraction, its high inhibitory activity was attributed to the presence of quercetin-7-O-galactoside which showed a high potent inhibition of the enzyme activity reaching 100% at 100 mg/mL reaction mixture. Phytochemical investigations of the water-soluble fraction were also carried out and afforded ten polyphenolic compounds including two new natural compounds, namely kaempferol- 7-O-[6´´´-O-p-hydroxybenzoyl-β-D-glucosyl-(1≙6)-β-D-glucopyranoside] and scutellarein-6- O-α-L-rhamnopyranoside-8-C-β-D-glucopyranoside). The chemical structure of the isolated compounds was elucidated on the basis of chemical and spectral data.


Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4294 ◽  
Author(s):  
Salhab ◽  
Naughton ◽  
Barker

The inhibitory effect of new chemical entities on rat liver P450 marker activities was investigated in a functional approach towards drug development. Treatment of colorectal cancer (CRC) and chemoprevention using salicylic acid has gained a lot of attention, mainly in the prevention of the onset of colon cancer. Thus, an in vitro inhibitory effect of salicylic acid on rat CYP2C11 activity was examined by using high performance liquid chromatography (HPLC). High performance liquid chromatography analysis of a CYP2C11 assay was developed on a reversed phase C18 column (SUPELCO 25 cm × 4.6 mm × 5 µm) at 243 nm using 32% phosphate buffer (pH 3.36) and 68% methanol as a mobile phase. The CYP2C11 assay showed good linearity for all components (R2 > 0.999). Substrates and metabolites were found to be stable for up to 72 hours. Additionally, the method demonstrated good reproducibility, intra- and inter-day precision (<15%), acceptable recovery and accuracy (80%–120%), and low detection (1.3501 µM and 3.2757 µM) and quantitation limit values (4.914 µM and 9.927 µM) for 16α-hydroxytestosterone and testosterone, respectively. Salicylic acid acts reversibly as a noncompetitive (weak) inhibitor with Ki = 84.582 ± 2.67 µM (concentration of inhibitor to cause 50% inhibition of original enzyme activity (IC50) = 82.70 ± 2.67 µM) for CYP2C11 enzyme activity. This indicates a low potential to cause toxicity and drug–drug interactions.


Parasitology ◽  
2003 ◽  
Vol 127 (3) ◽  
pp. 253-264 ◽  
Author(s):  
B. H. AL-ADHAMI ◽  
J. THORNHILL ◽  
A. AKHKHA ◽  
M. J. DOENHOFF ◽  
J. R. KUSEL

A variety of fluorescent probes have been used to study the acidic compartments in cercariae and schistosomula ofSchistosoma mansoni. Freshly transformed schistosomula treated with the LysoTracker Red dye specific for lysosomes showed large acid-containing compartments (0·5–10 μm in size). The uptake of the dye is an energy-dependent process that depends on the metabolic activity of schistosomula. The compartments were quantified individually with respect to area, quantity of fluorescence and the total number/schistosomulum. Under normal conditions these compartments were not found in untreated cercariae, but appeared in cercariae slightly damaged by poly-L-lysine. The formation of these compartments seemed to be related to the development of cercariae into schistosomula as the number of compartments and uptake of fluorescence increased with time after transformation. Also, the method of transformation as well as thein vitroincubation of the parasite affected the percentage area of compartments/schistosomulum. Acid phosphatase enzyme activity was assessed using an endogenous phosphatase probe. Living and fixed schistosomula displayed the presence of enzyme activity in compartments of the same size and distribution as the acid-rich compartments. This was confirmed by histochemical staining showing deposition of enzyme-generated lead at the sites of phosphatase activity. We suggest that the development of acidic compartments is important during the transformation process or as a consequence of damage.


2006 ◽  
Vol 42 (4) ◽  
pp. 298-301 ◽  
Author(s):  
Craig B. Webb ◽  
David C. Twedt

An adult dog with a persistent elevation in alkaline phosphatase enzyme activity was started on mitotane for suspected hyperadrenocorticism. One month later, the dog was presented for intermittent anorexia and acute icterus. The dog’s liver enzyme activities and total bilirubin were markedly elevated, prothrombin time was prolonged, and blood urea nitrogen and glucose were low. Histopathology revealed marked, centrilobular, hepatocellular loss. After discontinuation of the mitotane, the dog recovered with supportive care and was normal 3 months later, which was consistent with mitotane-associated hepatic failure.


1981 ◽  
Vol 97 (4) ◽  
pp. 491-495 ◽  
Author(s):  
S. Matsuzaki ◽  
M. Suzuki

Abstract. The effect of sodium perchlorate (NaClO4) on the methylthiouracil-induced increase in the activity of thyroid glucose 6-phosphate dehydrogenase (G6PDH), ornithine decarboxylase (ODC) and polyamine contents was studied in the rat. The G6PDH activity was increased nearly three-fold by methylthiouracil (MTU) but not by ClO4- at 7 days of treatment. Perchlorate lowered the MTU-induced enzyme activity to nearly the control level, without changing circulating thyrotrophin (TSH). The anion had no inhibitory effect on G6PDH activity in vitro. The possibility that an inhibitor specific for G6PDH was generated in ClO4- treated rat thyroids was excluded. The activity of ODC was greatly increased by both ClO4- and MTU, the increase being significant as early as on the second day of treatment. Perchlorate had no inhibitory effect on MTU-induced ODC activity in vivo but decreased total contents of spermidine and spermine in the thyroid, without affecting the concentration (nmoles/ g wet weight) of the polyamines. These results suggest that ClO4- acts directly on the thyroid to suppress specifically the stimulatory effect of TSH on G6PDH activity and possibly on polyamine accumulation.


Author(s):  
Kumari Smita

Objective: The present investigation was designed to study the inhibitory effects of methanolic leaf extract of Ocimum canum (O. canum) on α-glucosidase using in vitro model followed by an assessment of bioactive compounds.Methods: The methanolic leaf extract was prepared by Soxhlet extraction method and partially purified by thin layer chromatography (TLC). Each band was subjected to α-glucosidase inhibition study. The positive bands were further characterized by high-performance liquid chromatography (HPLC) and quadrupole time of flight (Q-TOF) micro mass spectrometer.Results: Out of the several combinations of solvent systems, toluene, ethyl acetate and formic acid combination in the ratio of 7:2:1 revealed 5 bands on the TLC sheet. Among all the TLC bands, 2 bands (band A and B) showed the significant inhibitory effect on α-glucosidase activity. HPLC analysis of band A and B revealed the presence of two important polyphenolic compounds, namely rosmarinic acid (RA) and ursolic acid (UA). Q-TOF micromass spectrometer analysis revealed the percentage availability of RA, caffeic acid, tartaric acid, quercetin and other polyphenolic components in the bioactive bands.Conclusion: The study revealed that methanolic leaf extract of O. canum exhibits potent inhibition of α-glucosidase activity. Inhibition of α-glucosidase activity might be attributed to the presence of the polyphenolic compounds like RA and UA. Therefore, this finding can lead to the development of natural α-glucosidase inhibitors by the O. canum leaf extract.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1184
Author(s):  
Przemysław Łukasz Kowalczewski ◽  
Małgorzata Gumienna ◽  
Iga Rybicka ◽  
Barbara Górna ◽  
Paulina Sarbak ◽  
...  

Cricket powder, described in the literature as a source of nutrients, can be a valuable ingredient to supplement deficiencies in various food products. Work continues on the implementation of cricket powder in products that are widely consumed. The aim of this study was to obtain gluten-free bread with a superior nutritional profile by means of insect powder addition. Gluten-free breads enriched with 2%, 6%, and 10% of cricket (Acheta domesticus) powder were formulated and extensively characterized. The nutritional value, as well as antioxidant and β-glucuronidase activities, were assessed after simulated in vitro digestion. Addition of cricket powder significantly increased the nutritional value, both in terms of the protein content (exceeding two-, four-, and seven-fold the reference bread (RB), respectively) and above all mineral compounds. The most significant changes were observed for Cu, P, and Zn. A significant increase in the content of polyphenolic compounds and antioxidant activity in the enriched bread was also demonstrated; moreover, both values additionally increased after the digestion process. The total polyphenolic compounds content increased about five-fold from RB to bread with 10% CP (BCP10), and respectively about three-fold after digestion. Similarly, the total antioxidant capacity before digestion increased about four-fold, and after digestion about six-fold. The use of CP also reduced the undesirable activity of β-glucuronidase by 65.9% (RB vs. BCP10) in the small intestine, down to 78.9% in the large intestine. The influence of bread on the intestinal microflora was also evaluated, and no inhibitory effect on the growth of microflora was demonstrated, both beneficial (Bifidobacterium and Lactobacillus) and pathogenic (Enterococcus and Escherichia coli). Our results underscore the benefits of using cricket powder to increase the nutritional value and biological activity of gluten-free food products.


1977 ◽  
Vol 166 (3) ◽  
pp. 429-435 ◽  
Author(s):  
G. Subba Rao ◽  
Leonard N. Norcia ◽  
Joanne Pieringer ◽  
Ronald A. Pieringer

Triton X-100 extracts of rat brain microsomal fraction catalyse the formation of sulphogalactosyldiacylglycerol from galactosyldiacylglycerol and adenosine 3′-phosphate 5′-sulphatophosphate. Of the various subcellular fractions of brain assayed, the microsomal fraction contained most (79%) of the adenosine 3′-phosphate 5′-sulphatophosphate–galactosyldiacylglycerol sulphotransferase activity. The enzyme activity was stimulated by Triton X-100 and showed linearity with increasing time, concentrations of enzyme and added substrates. ATP and KF prolonged the linearity of the activity with time, but ATP had an overall inhibitory effect on the sulphotransferase. Both ATP and KF inhibit the degradation of adenosine 3′-phosphate 5′-sulphatophosphate, which probably causes the increased linearity of the sulphotransferase reaction with time. The enzyme preparation did not catalyse the transfer of sulphate from adenosine 3′-phosphate 5′-sulphatophosphate to either cholesterol or galabiosyldiacylglycerol (galactosylgalactosyldiacylglycerol). Significant differences between the formation of sulphogalactosyldiacylglycerol and cerebroside sulphate catalysed by the same enzyme preparation were noted. ATP and Mg2+ strongly inhibit the formation of sulphogalactosyldiacylglycerol but equally strongly stimulate the synthesis of cerebroside sulphate. The apparent Km for galactosyldiacylglycerol is 200μm, and that for cerebroside is 45μm. Galactosyldiacylglycerol and cerebroside are mutually inhibitory toward the synthesis of sulphated derivatives of each. These data do not necessarily lead to the conclusion that two sulphotransferases are present, but they do indicate a possible means of controlling the synthesis of these two sulpholipids.


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