Chromatographic Subfractions Research Articles

In Vitro Antimalarial Susceptibility of Plasmodium falciparum and Plasmodium berghei Isolates to Selected Antimalarial Agents, Column Chromatographic Subfractions of Glyphaea brevis Leaves Extract and FTIR and GCMS of SF8.

Malaria still remains a life-threatening parasitic disease with universal targets set for control and elimination. This study aimed to evaluate the in vitro antimalarial susceptibility of Plasmodium falciparum isolates and Plasmodium berghei to selected antimalarial agents and column chromatographic subfractions of Glyphaea brevis leaves extract and FTIR and GCMS of SF8. Trager and Jensen as well as World Health Organisation (WHO) standardised in vitro micro-test system methods were used to determine susceptibility on the patients' blood samples; Column chromatographic procedure was carried out to obtain 11 pooled fractions; FTIR and GCMS were used to determine functional groups and phytochemicals respectively. In vitro anti-plasmodial activity against P. falciparum clinical isolates had IC50 range of 1.03 μg/mL-7.63 μg/mL while their IC50 against P. berghei ranges from 4.32 μg/mL-7.89 μg/mL. Subfraction 8 (SF8) had the least IC50 of 4.32 μg/mL. The FTIR spectrum showed the presence of isoprenoid, alcohol, phenol, alkane, alkenes, ester, carboxylic acids, aromatics and nitro compounds while GCMS identified dodecanoic acid, methyl ester; carotol; hexadecanoic acid, methyl ester; 9-octadecenoic acid (Z)-, methyl ester (oleic acid); methyl stearate; heptadecanoic acid, 16-methyl-, methyl ester; all with their antimalarial reported activities. In conclusion, G. brevis has a great potential for drug development against malaria parasite since it inhibited schizont growth and possesses phytocompounds with antimalarial report.

Evaluation of the anti-proliferative and cytotoxic potentials of fractions of methanol leaf extract of Cnidoscolus aconitifolius

The partitioned aqueous and chloroform fractions obtained from the methanol extract of the leaf of Cnidoscolus aconitifolius were examined for anti-proliferative (1-30 mg/mL) and cytotoxic activities (20-400 μg/mL) using the seed radicle inhibition and tadpole mortality assays over a period of 24 and 96 h respectively. The vacuum liquid chromatographic sub-fractions of the active chloroform fraction weresimilarly evaluated at 1-10 mg/mL and 5-20 μg/mL concentrations respectively. At 100 μg/mL the chloroform fraction produced 86.67 % mortality which increases to 100 % at 400 μg/mL where the aqueous fraction gave 36.67 %. The potency was further increased as the VLC sub-fractions C4-C6, gave 33 % cytotoxicity at 5 μg/mL and which later increased to 100 % at 10 μg/mL. At the end of 96 h, the control seed had average length of 32.32 ± 2.73 mm compared to 1.92 ± 0.36 and 0.52 ± 0.36 mm observed in the seeds treated with 20 and 30 μg/mL of the chloroform fraction indicating 94.01 and 98.39 % inhibition where as there was total radicle growth inhibition (100 %) of seeds treated with 5 mg/mL of the active VLC sub-fractions (C1-3, C4-C6 and C7). The results showed a significant cytotoxic and growth inhibitory effects of the plant extract, particularly the chloroform fraction and its sub-fractions which further corroborate the folkloric use of the plant in treating cancer. However, further chromatographic analysis of the active VLC sub-fraction and their respective biological studies using cancer cell-lines are needed to support this.Keywords: Cnidoscolus aconitifolius, Sorghum bicolor, anti-proliferative, cytotoxicity, methanol extract, aqueous fraction, chloroform extract , vacuum liquid chromatography,

Potential of Szechuan pepper as a saltiness enhancer

ABSTRACTThe flavor profile, flavor enhancement, and saltiness modulation of Szechuan pepper (Zanthoxylum simulans) were analyzed to evaluate its effectiveness in lowering salt usage. The saltiness enhancing efficiency of Szechuan pepper and its salt-reduction properties were determined to be 28.74% and 22.32%, respectively. The saltiness enhancers were detected in the polar fraction and taste dilution analysis combined with half-tongue test determined the most potent saltiness enhancing components in chromatographic subfractions. Both spectroscopic analysis and sensory evaluation disclosed NaCl as the unexpected primary contributor of saltiness enhancement in this spice. It is the first known study revealing Szechuan pepper’s high salt content.

Improving compositional space accessibility in (+) APPI FT-ICR mass spectrometric analysis of crude oils by extrography and column chromatography fractionation

Separation strategies coupled with HRMS analysis are vital to increase the scope of the instrumental technique. In this work, we use extrography and column chromatography as fractionation tools for increasing compositional space accessibility in the APPI-FT-ICR mass spectrometric analysis of heavy crude oils. Extrography fractionation was performed on a crude oil sample adsorbed on neutral alumina, using an elutropic series. The crude oil was adsorbed on neutral alumina, and then we applied Soxhlet extraction using acetonitrile, methanol, n-heptane, and toluene, to obtain fractions enriched in metal complexes, polar compounds, maltenes, and asphaltenes, respectively. Considering that polar compounds are responsible for complex operational problems such emulsion and deposit formation, we fractioned the polar extract using normal phase column chromatography to obtain six additional subfractions. All of the extracts were analyzed by APPI FT-ICR mass spectrometry. We detected eleven compound classes in fractions and sub-fractions which were undetectable when analyzing the entire crude oil sample. In terms of the number of molecular formulas, the whole crude oil sample exhibits ∼3700 while ∼11,800 compounds were detected in extrography fractions and column chromatographic sub-fractions. These results indicate that combination of extrography and column chromatography increase compositional space accessibility in around 70%. Specifically, fractionation processes allowed the detection of several compound classes such as NnSs, NnOo, OoSs, NnOoSs (with n=1; s=1, 2, 3; o=1, 2, 3), and N4O1V1, which were undetectable in the analysis of the whole crude oil.

Hypoglycaemic and hypolipidaemic effects of crude extracts and chromatographic fractions of Morinda morindoides root bark in diabetic rats

Hypoglycaemic and hypolipidaemic effects of different extracts and fractions of root bark from the plantMorinda morindoides(Baker) Milne-Redh of the familyRubiaceaewere evaluated in alloxan-induced diabetic rats. The aqueous and methanolic extracts were administered to 48 rats orally at a dose of 400 mg·kg-1for 21 days.Fractions (hydromethanol, hexane, chloroform and ethyl acetate) from bio-activity guided fractionation and chromatographic sub fractions (CsF) A-F from accelerated gradient chromatography were also evaluated in 45 rats for the hypoglycaemic activity at doses of 400 mg·kg-1, 200 mg·kg-1and 100 mg·kg-1of solvent fractions and (CsF) A-F, respectively. Glibenclamide was used as positive control. Polyoxyethylene sorbitan monooleate and distilled water administered to rats were used as negative controls. The dose of 400 mg·kg-1of aqueous and methanolic extracts and 100 mg·kg-1of chloroformCsFB ofMorinda morindoidescaused (62.8%, 56% and 74%, respectively) reductions in blood glucose level (BGL). The aqueous extract caused significant (P< 0.05) decreases in the values of serum cholesterol (133.48 ± 1.1) mg·dl-1, low density lipoprotein (66.38 ± 2.5) mg·dl-1and significant (P< 0.05) increase in the value of high density lipoprotein (51.03 ± 3.0) mg·dl-1when compared to the control. These results confirm the folkloric claim of the hypoglycaemic and hypolipidaemic activities ofMorinda morindoidesroot bark.

Effects on cell proliferation and EPR spin trapping studies of Abnormal Savda Munziq and its chromatographic subfractions

Effects on cell proliferation and EPR spin trapping studies of Abnormal Savda Munziq and its chromatographic subfractions

New Trichobrachins, 11-residue peptaibols from a marine strain of Trichoderma longibrachiatum

A marine strain of Trichoderma longibrachiatum isolated from blue mussels ( Mytilus edulis) was investigated for short peptaibol production. Various 11-residue peptaibols, obtained as microheterogenous mixtures after a chromatographic fractionation, were identified by positive mass spectrometry fragmentation (ESI-IT-MS n, CID-MS n and GC/EI-MS). Thirty sequences were identified, which is the largest number of analogous sequences so far observed at once. Twenty-one sequences were new, and nine others corresponded to peptaibols already described. These peptaibols belonged to the same peptidic family based on the model Ac-Aib-xxx-xxx-xxx-Aib-Pro-xxx-xxx-Aib-Pro-xxol. They were named trichobrachin A when the residue in position 2 was an Asn, and trichobrachin C when it was a Gln. Major chromatographic sub-fractions, corresponding to purified peptaibols, were assayed for their cytotoxic activity. Trichobrachin A-IX and trichobrachin C exhibited the highest activities. There was an exponential relation between their relative hydrophobicity and their cytotoxicity on KB cells.

Cytotoxic Fractions from the Leaves of Tachia grandiflora.

This work is part of a larger screening program, which seeks to discover new antitumor plants and compounds from the Brazilian Amazon. In a prescreen of stem and leaf extracts of Tachia grandiflora. Maguire & Weaver (Gentianaceae) based on the SRB method, leaf methanol and ethanol extracts showed appreciable cytotoxicity in human breast (MCF-7) and colon (HCT-8) tumor cell lines. Liquid-liquid partitioning of the leaf ethanol extract yielded hexane, chloroform, butanol, and water-methanol fractions. Only the hexane and chloroform fractions were active, inhibiting murine melanoma (B-16) and HCT-8 cells. The chloroform fraction suffered sequential column chromatography on silica gel using different eluent systems and yielded a number of very active subfractions. In all, 25 fractions and subfractions were tested, and 10 exhibited high growth inhibition of HCT-8, and two of these presented strong inhibition of murine melanoma (B-16) cells. The most active subfractions were tested against five tumor cell lines (leukemia CEM and HL-60, as well as the three used previously) using the MTT assay, and four fractions demonstrated significant cytotoxicity based on IC50. Cell lysis was discarded as a possible mechanism for in vitro. cytotoxicity given that these fractions did not exhibit hemolytic activity. The greatest antiproliferative potential was found in the second (two samples) and third generation (two samples) chromatographic subfractions of the chloroform fraction (obtained from partitioning of the ethanol extract). These subfractions proved to be complex mixtures from which no pure substance could be isolated after further chromatographic separations.

Antiradical properties of sorghum (Sorghum bicolor L. Moench) flour extracts

Epidemiological studies support the belief that whole grains are protective against several chronic diseases. The health benefits of whole grains are attributed in part to their unique phytochemical composition. Major phytochemicals in grains include various classes of phenolic compounds, flavonoids and coumarin derivatives, etc. Phenolic compounds present in grains possess antioxidant properties that are associated with the health benefits of grains and grain products. Sorghum is one of the main staple cereal grains in hot dry tropics and ranks fifth among cereal crops in the world. Although sorghum is rich in phenolics and tannins which are proven anticancer and cardioprotective constituents, human consumption of sorghum is limited. To our knowledge, there is limited literature on the profile of antioxidant phytochemicals in the local white variety of sorghum. Hence, the objective of this study was to investigate the antioxidant property of white sorghum flour extracts in vitro and also to identify the fractions responsible for the antioxidant activity. In the present study, we analyzed the antioxidative properties of various extracts (water, 60% methanol, 60% ethanol, and 60% t-butanol) of white sorghum flour employing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) model system. Phenolics, antiradical and antioxidant activities were also examined in chromatographic sub-fractions of the soxhlet methanolic extract. Our results indicated that the various extracts exhibited significant antioxidant activity that did not correlate with the phenolic content. Further, two sub-fractions eluted with methanol and acetone/methanol were found to possess strong antioxidant activity in two assay systems. Our results suggest that a diet rich in sorghum may be useful in combating diseases in which free radical production plays a key role.

CHARACTERIZATION OF ACIDS IN SHALE OIL HIGH-BOILING DISTILLATES

ABSTRACT A chromatographic-infrared method has been used for the separation and characterization of acid compound types in shale oil high-boiling distillates. Acid compound concentrates are separated by high performance liquid chromatography (HPLC) on basic alumina, and the chromatographic subfractions are analyzed by quantitative infrared spectrometry. The analyses are reproducible, and generally 90 percent or more of the material is analyzed. Major acid compound types identified in shale oils are phenols, pyrrolic nitrogen compounds, and amides.

Functional evaluation of an inherited abnormal fibrinogen: fibrinogen "Baltimore".

The rate of clotting and the rate of development and degree of turbidity after addition of thrombin to plasma or purified fibrinogen from a patient with fibrinogen Baltimore was delayed when compared with normal, especially in the presence of low concentrations of thrombin. Optimal coagulation and development of translucent, rather than opaque, clots occurred at a lower pH with the abnormal fibrinogen than with normal. Development of turbidity during clotting of the abnormal plasma or fibrinogen was less than normal at each pH tested, but was maximal in both at approximately pH 6.4. The physical quality of clots formed from fibrinogen Baltimore was abnormal, as demonstrated by a decreased amplitude on thromboelastography. The morphologic appearance of fibrin strands formed from fibrinogen Baltimore by thrombin at pH 7.4 was abnormal when examined by phase contrast or electron microscopy, but those formed by thrombin at pH 6.4 or by thrombin and calcium chloride were similar to, though less compact, than normal fibrin. The periodicity of fibrin formed from fibrinogen Baltimore was similar to normal and was 231-233 A.A study of the release of the fibrinopeptides from the patient's fibrinogen and its chromatographic subfractions verified the existence of both a normally behaving and a defective form of fibrinogen in the patient's plasma. The defective form differed from normal in three functionally different ways: (a) the rate of release of fibrinopeptides A and AP was slower than normal; (b) no visible clot formation accompanied either partial or complete release of the fibrinopeptides from the defective form in 0.3 M NaCl at pH 7.4; and (c) the defective component possessed a high proportion of phosphorylated, relative to nonphosphorylated, fibrinopeptide A, while the coagulable component contained very little of the phosphorylated peptide (AP). The high phosphate content of the defective component did not appear to be the cause of the abnormality, but may be the result of an associated metabolic or genetic phenomenon.

Biologic Activities of Aggregated γ-Globulin

Summary Rabbit α-globulin, β1-globulin and subfractions of γ-globulin were aggregated by coupling with bis-diazotized benzidine and the aggregated products were studies for skin reactivity in normal guinea pigs and for C′-fixing properties. Induction of these biological activities upon nonspecific aggregation was characteristic of γ-globulin only. Aggregated products of neither α-globulin nor β1-globulin had either activity. Evidence was presented that only γ-globulin had affinity for guinea pig tissues to which antibody combines upon passive sensitization. All three of these properties, namely skin reactivity and C′-fixing activity upon aggregation, and affinity for guinea pig tissue were present approximately equally in all the chromatographic subfractions of γ-globulin. All γ-globulin subfractions of rabbit anti-ovalbumin sera contained antibody. Soluble antigen-antibody complexes prepared with these fractions gave skin reactions in normal guinea pigs and inactivated C′. On a weight basis, the soluble complexes and nonspecifically aggregated γ-globulin were comparable with respect to these biologic activities.

An enzyme system in the gastric secretion capable of reducing the viscosity of native soluble calf-skin collagen

Gastric juice from various animals contained an enzyme system capable of reducing the viscosity of a solution of native calf-skin collagen. These enzymes were confined in their action to the end-chains of collagen and could not be classified as collagenases. The end-chains contributed approx. 30% of the initial solution viscosity of collagen. Commercial preparations of pepsin (EC 3.4.4.1) differed in their ability to reduce the viscosity of collagen. Chromatographically homogeneous pepsin and three chromatographic subfractions (pepsins B, C and D) were demonstrated to have different actions on soluble collagen as indicated by viscosity changes. The individual pepsin enzymes had characteristic affinities for collagen and probably had different substrate specificities. The different actions of commercial pepsins on collagen could be accounted for by the presence of pepsin plus one or more of the more active subfractions. It was suggested that one sample of commercial crystalline pepsin and also human gastric juice contained a pepsin-like enzyme, other than any of the subfractions at present isolated, which was very much more active than any purified pepsin.