Gas-liquid Chromatographic Analysis Research Articles

Identification of the Botanical Origin of Commercial Pine Nuts Responsible for Dysgeusia by Gas-Liquid Chromatography Analysis of Fatty Acid Profile

Over the last 10 years, complaints were increasingly reported from consumers that experienced dysgeusia following the consumption of pine nuts. In the present study, pine nuts samples (N = 16) from consumers that reported dysgeusia have been analyzed to identify the botanical origin of critical pine nuts samples. The fatty acid composition of the samples was performed, and diagnostic index values were used to identify the botanical origin of the samples. Pinus armandii nuts were identified in all the samples pure or in mixture with P. koraiensis nuts. P. armandii is not reported as edible pine nuts by the Food and Agriculture Organization (FAO). This study confirmed that consumption of P. armandii nuts may lead to dysgeusia. Based on the present study and previous work, we advise import companies to trade pine nuts from traditionally recognized species such as P. pinea, P. sibirica, P. koraiensis, or P. gerardiana.

PENELITIAN PEMBUATAN POLI METIL METAKRILAT

The poly methyl methacrylate (PMMA) research has been excecuted. Methyl methacrylate is polymerized by the free radical inisiation with the suspension condition using benzoyl peroxyde inisiator, water as a solution and the gelatine stabilizer, in this reseaarch is executed as a standard ratio (part per part:monomer : water : stabilizer = 100 : 350 : (0.1 1) with the inisiator to monomer ratio variation (part per part) are: 0.1 per 50; 0,175 per 50; 0,25 per 50; 0,25 per 50, the temperature variation are : 30 degree C, 45 degree C, 60 degree C and the time polymerization until 320 minutes. The result showed that the optimum monomer polymerizeation was at the inisiator to monomer ratio 0,25 per 50, the temperature at 45 degree C and at the time polymerization until 300 minutes with the monomer conversion was 86 percent. The Infra Red Spectroscopy analyses showed that there are poly methyl methacrylate in the product. The Gas Liquid Chromatography analysis showed the evolution of the monomer (methil methacrylate concetration.

Degradation of Prochloraz by Rice Bakanae Disease Pathogen Fusarium fujikuroi with Differing Sensitivity: a Possible Explanation for Resistance Mechanism

The fungicide prochloraz was subjected to degradation by the pathogen causing rice Bakanae disease, Fusarium fujikuroi, in order to gain an insight into the mechanisms of sensitivity and resistance to the fungicide. Growth-inhibiting assays of pathogens conducted on potato dextrose agar (PDA) plates by a paper-disc agar-diffusion method. Significant growth inhibition of the sensitive strain CF106 was observed at the recommended treatment level of prochloraz, whereas negligible growth inhibition of the resistant strain CF245 was observed at the same treatment level. The strain CF245 was shown to be able to grow on PDA with 500 mg/L of the fungicide, which is significantly higher than its recommended treatment level. Growth-inhibiting assays of pathogens were also conducted in potato dextrose broth (PDB) medium supplemented with prochloraz at different concentrations, measuring their biomass weights over the incubation period. Significant growth inhibition was observed in the strain CF106 at a level of 0.5 mg/L, but negligible growth inhibition was observed in the strain CF245 at the same treatment level with the strain CF106. The strain CF245 could grow in PDB supplemented with 1.0 mg/L of prochloraz. The degradation of prochloraz by the two strains was evaluated by gas liquid chromatography and mass spectrometry analyses. The strain CF245 completely degraded 1.0 mg/L of prochloraz in 5 days after incubation, whereas no degradation of prochloraz was observed by the strain CF106 at the same treatment level. Liquid chromatography Q-TOF MS detected N-(2-(2,4,6-trichlorophenoxy)ethyl)propan-1-amine as a major degradation product of prochloraz by the strain CF245. These results indicated that the degradation of prochloraz may account for the reduced sensitivity of the strain CF245 to prochloraz.

Major lipid classes and their fatty acids in a parasitic nematode, Ascaridia galli

The paper presents major lipid classes and their fatty acids investigated from Ascaridia galli, a nematode parasite of country fowl. Thin layer chromatography (TLC) reveals that the percent of total lipid, neutral lipid, phospholipids, and glycolipids are 1.94, 54.39, 26.95 and 18.66, respectively. Gas-liquid chromatography (GLC) analysis shows that the saturated fatty acids are the major components in all the lipid fractions followed by monoenes and dienes. Polyunsaturated fatty acids (PUFA) were present in low amount. Stearic acids (C(18)) were the chief components among all the fatty acids in all the lipid fractions.

Differential antibacterial activities of fusiform and oval morphotypes of Phaeodactylum tricornutum (Bacillariophyceae)

The diatom, Phaeodactylum tricornutum is a common inhabitant of inshore waters and can exist in different morphotypes that are thought to be adapted for survival in different habitats. Despite this diatom being widely used for physiological and genetic studies of microalgae, little is known about biochemical or physiological differences between the cell morphotypes. The present study was aimed at comparing differences in the antibacterial properties of the fusiform and oval morphotypes, the dominant cell types found in laboratory cultures of most strains of P. tricornutum. In cultures differing in proportions of fusiform and oval cells, there is a significant and positive correlation between the proportion of cells in the fusiform morphotype and the antibacterial activity of cell extracts. Extracts prepared from cultures enriched for fusiform cells (~76%) show greater antibacterial activity against the Gram-positive bacterium, Staphylococcus aureus, than those prepared from pure (100%) oval cultures. Thus fusiform cells contain greater antibacterial activity per cell compared to the ovals. Gas–liquid chromatographic analyses of the extracts reveal that those from enriched fusiform populations contain significantly greater levels of the free fatty acids, eicosapentaenoic acid (EPA), hexadecatrienoic acid (HTA) and palmitoleic acid (PA) than the pure oval cell cultures. These free fatty acids from P. tricornutum have been previously shown by us to have potent antibacterial activity against S. aureus. Free fatty acids, released from damaged microalgal cells, defend the microalgal population against grazing predators but, here, we suggest that these free fatty acids could also act against pathogenic bacteria in the vicinity of the algae. As cell extracts from the fusiform cells contain greater quantities of these fatty acids, fusiform cells may have greater potential than the ovals for this type of protection.

Correlation of omega-3 levels in serum phospholipid from 2053 human blood samples with key fatty acid ratios.

BackgroundThis research was conducted to explore the relationships between the levels of omega-3 fatty acids in serum phospholipid and key fatty acid ratios including potential cut-offs for risk factor assessment with respect to coronary heart disease and fatal ischemic heart disease.MethodsBlood samples (n = 2053) were obtained from free-living subjects in North America and processed for determining the levels of total fatty acids in serum phospholipid as omega-3 fatty acids including EPA (eicosapentaenoic acid, 20:5 n-3) and DHA (docosahexaenoic acid, 22:6 n-3) by combined thin-layer and gas-liquid chromatographic analyses. The omega-3 levels were correlated with selected omega-6: omega-3 ratios including AA (arachidonic acid, 20:4n-6): EPA and AA:(EPA+DHA). Based on previously-published levels of omega-3 fatty acids considered to be in a 'lower risk' category for heart disease and related fatality, 'lower risk' categories for selected fatty acid ratios were estimated.ResultsStrong inverse correlations between the summed total of omega-3 fatty acids in serum phospholipid and all four ratios (omega-6:omega-3 (n-6:n-3), AA:EPA, AA:DHA, and AA:(EPA+DHA)) were found with the most potent correlation being with the omega-6:omega-3 ratio (R2 = 0.96). The strongest inverse relation for the EPA+DHA levels in serum phospholipid was found with the omega-6: omega-3 ratio (R2 = 0.94) followed closely by the AA:(EPA+DHA) ratio at R2 = 0.88. It was estimated that 95% of the subjects would be in the 'lower risk' category for coronary heart disease (based on total omega-3 ≥ 7.2%) with omega-6:omega-3 ratios <4.5 and AA:(EPA+DHA) ratios <1.4. The corresponding ratio cut-offs for a 'lower risk' category for fatal ischemic heart disease (EPA+DHA ≥ 4.6%) were estimated at < 5.8 and < 2.1, respectively.ConclusionsStrong inverse correlations between the levels of omega-3 fatty acids in serum (or plasma) phospholipid and omega-6: omega-3 ratios are apparent based on this large database of 2053 samples. Certain fatty acid ratios may aid in cardiovascular disease-related risk assessment if/when complete profiles are not available.

EFFECT OF COLD STORAGE AND DIFFERENT PACKAGING MATERIALS ON THE QUALITY OF FRESH ROSEMARY HERB: II- EFFECT ON THE ESSENTIAL OIL PERCENTAGE AND COMPOSITION.

Fresh culinary herbs are one of the fastest growing markets for gourmet production on a world wide scale. Some herbs are sold fresh rather than dry because they do not retain their flavor when dried. Rosemary (Rosmarinus officinalis L.) plant is an important aromatic culinary herb. Essential oil of rosemary is considered one of the strongest natural antioxidants. A study was carried out during two successive summer seasons 2006 and 2007, at the Post Harvest Lab in the Vegt. and Floric. Dept., Fac. of Agric., MonsouraUniv. This part (II) aimed to investigate the effect of cold storage temperatures and different packaging materials on the essential oil percentage and composition of fresh rosemary herb and the changes that took place during storage until the end of their shelf life as fresh herbs. Fresh rosemary herbs were packaged in nine different packaging materials: Butter bags (P1), Cellophane bags (P2), Nylon bags (P3), Polyethylene bags (P4), Aluminum foils (P5), Aluminum plates covered with foil (P6), Aluminum plates covered with plastic film (P7), Foam plates covered with foil (P8), Foam plates covered with plastic film (P9), and then stored at (1, 3, and 5 °C) for 6 weeks. Gas Liquid Chromatography (G.L.C.) analysis was carried out in second season summer 2007 to compare between the composition of the oil of the freshly harvested herb and the of oil of herbs packaged in Aluminum plates covered with foil (the package that gave best marketability for fresh herb shown in Part 1) after one and three weeks of storage under the three cold storage temperatures. The results showed that the essential oil percentage of the herb increased with increasing the length of the storage period. Oil percentage in herbs stored at 3 °C was superior to those stored under the other two temperatures in both seasons. Herbs kept in Butter bags (P1) had maximum oil percentage until the second week of storage. Cellophane bags (P2) were the highest in the fourth week of storage, while at the fifth week of storage; Foam plates covered with foil (P8) was the highest. At the end of six weeks of storage at 3 C only Aluminum plates covered with foil (P6) and Aluminum foils (P5) were marketable in both seasons, but (P6) had higher oil percentage than (P5). GLC analysis identified 14 compounds constituted 88.8 % of the essential oil of rosemary fresh herb after harvest (control). The identified compounds included seven hydrocarbons forming 57.25 % and seven oxygenated forming 31.55 % of the total compounds. Hydrocarbons were α- pinene (11.93 %), β- pinene (7.01 %), limonene (3.01 %), ρ- cymene (10.11%), camphene (7.94 %), γ- terpinene (9.23 %), and α- terpinolene (8.02 %). Oxygenated compounds were 1,8 cineole (7.27 %), linalool (6.79 %), verbenol (1.94 %), borneol (3.83 %), thymol (4.47 %), camphor (2.3 %), and terpineol (4.95 %). The total percentage of hydrocarbons and oxygenated compounds decreased after storage compared with the control. The total percentage of each of hydrocarbons and oxygenated compounds were higher at 3°C than those at either 1 or 5 °C at the two comparable storage periods. At a storage temperature of 3°C, all hydrocarbons had higher percentages after one week of storage than after three weeks of storage, except for β-pinene and limonene, while all oxygenated compounds had higher percentages after three weeks of storage than after one week of storage, except for thymol and terpineol.

Varibaculum cambrienseInfections in Hong Kong, China, 2006

<i>Varibaculum cambriense</i>Infections in Hong Kong, China, 2006

PHYSICO-CHEMICAL AND BIOLOGICAL HARACTERISTICS OF CAMEL MILK

The present study was carried out to investigate some of the physical and principal chemical components of milk from the camel (Camelus dromedarius). A wide variation was observed in the components of raw camel milk. The average contents of physical parameters were 6.70 for pH, 0.19 % acidity, 1.029specific gravity. The chemical components were 11.30 % total solids, 4.40 % fat, 8.12 % solids not fat, 2.91 % protein, 3.18 % lactose and 0.90 % ash. The highest level of glutamic acid was detected in camel milk, while it had a lower ratio of lysine than that of cow milk. There were noticeably higher levels of proline, aspartic, therionine, valine and leucine, respectively, while a lower values of cystine and methionine in camel milk. Gas liquid chromatography analysis of camel milk fat indicated that the short chain-fatty acids (C4-C12) were present in very low percentages, while the concentration of long chain-fatty acids were high such as saturated fatty acids (C14, C16 and C18) and polyunsaturated fatty acids (mainly C18:1). Also, the fatty acids in camel milk showed a higher degree of unsaturation, with especially relative high quantities of the essential fatty acids like linolenic (C18:3) and linoleic (C18:2) acids.

Comparison of Catalysts for Direct Transesterification of Fatty Acids in Freeze‐Dried Forage Samples

Preparation of fatty acid methyl esters from forages comparing methanolic boron‐trifluoride (BF3) to methanolic hydrochloric acid (HCl) as a catalyst in single‐step direct transesterification has not been reported. Our objective was to compare 1.09 M methanolic HCl to 1.03 M (7%) methanolic BF3 as catalysts for direct transesterification of fatty acids in freeze‐dried forage samples. Thin‐layer chromatographic analysis revealed complete conversion of total lipid extracts to fatty acid methyl esters using both catalysts. Additionally, gas–liquid chromatography analysis confirmed similar (P = 0.95) total fatty acid concentrations for both catalysts. Regression analysis indicated that similar values for total concentration would be obtained (P &lt; 0.0001; r2 = 0.96; slope = 0.98 ± 0.03) between the two catalysts. Concentrations of most individual fatty acids were similar (P = 0.17–0.99) for both catalysts. Summed weight percentages of identified fatty acids, as well as sum of unidentified peaks, were not affected (P = 0.27) by catalyst (91.8 and 8.7% vs. 90.8 and 9.2% for HCl and BF3, respectively). We conclude that 1.09 M methanolic HCl is an appropriate substitute for 1.03 M methanolic BF3 for preparation of fatty acid methyl esters from freeze‐dried forage samples. This result is of interest because HCL is both less costly and less caustic than BF3

A Floral-Derived Compound Attractive to the Tephritid Fruit Fly Parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae)

Many adult hymenopteran parasitoids, even host-feeding species, consume the nectar of flowering plants. Previous field studies had identified plants attractive (Lobularia maritima L.) and unattractive (Spermacoce verticillata L) to certain opiine braconids (Hymenoptera). Under laboratory conditions, Diachasmimorpha longicaudata (Ashmead), a parasitoid of tephritid fruit fly larvae and representative opiine, responded in flight tunnels to L. maritima but not to S. verticillata. Volatile chemicals of the two flowers were collected and analyzed by using capillary gas liquid chromatography and mass spectral analysis. Acetophenone was isolated from L. maritima but not from S. verticillata. In flight tunnels, D. longicaudata were exposed to 10 concentrations (doses) of acetophenone. Female parasitoids showed a significant attraction to several acetophenone doses, with concentrations of 25 and 50 ng the most attractive. No odor source, either floral or floral-derived, was attractive to male parasitoids. Reliable trapping systems for parasitoid species, particularly species such as D. longicaudata used for augmentative biological control, would be a valuable monitoring tool. At present, there are few, if any, florally derived synthetic lures for attracting hymenopteran parasitoids.

Two novel oligosaccharides isolated from a beverage produced by fermentation of a plant extract

An extract from 50 kinds of fruits and vegetables was fermented to produce a new beverage. Natural fermentation of the extract was carried out mainly by lactic acid bacteria ( Leuconostoc spp.) and yeast ( Zygosaccharomyces spp. and Pichia spp.). Two new saccharides were found in this fermented beverage. The saccharides were isolated using carbon–Celite column chromatography and preparative high performance liquid chromatography. Gas liquid chromatography analysis of methylated derivatives as well as MALDI-TOF MS and NMR measurements were used for structural confirmation. The 1H and 13C NMR signals of each saccharide were assigned using 2D-NMR including COSY, HSQC, HSQC-TOCSY, CH 2-HSQC-TOCSY, and CT-HMBC experiments. The saccharides were identified as β- d-fructopyranosyl-(2→6)-β- d-glucopyranosyl-(1→3)- d-glucopyranose and β- d-fructopyranosyl-(2→6)-[β- d-glucopyranosyl-(1→3)]- d-glucopyranose.

Hydrocarbon Utilization by Nodule Bacteria and Plant Growth-Promoting Rhizobacteria

Standard and locally isolated nodule bacteria and plant growth-promoting rhizobacteria (PGPR) were grown on crude oil and individual pure hydrocarbons as sole sources of carbon and energy. The nodule bacteria included two standard Rhizobium leguminosarum strains, two standard Bradyrhizobium japonicum strains, and one unknown nodule bacterial strain that was locally isolated from Vicia faba nodules. The PGPR included one standard Serratia liquefaciens strain and two locally isolated strains of Pseudomonas aeruginosa and Flavobacterium sp. The pure hydrocarbons tested included n-alkanes with chain lengths from C9 to C40 and the aromatic hydrocarbons benzene, biphenyle, naphthalene, phenanthrene, and toluene. Quantitative gas liquid chromatographic analyses confirmed that pure cultures of representative nodule bacteria and PGPR could attenuate n-octadecane and phenanthrene in the surrounding nutrient medium. Further, intact nodules of V. faba containing bacteria immobilized on and within those nodules reduced hydrocarbon levels in a medium in which those nodules were shaken. It was concluded that legume crops are suitable phytoremediation tools for oily soil, since they enrich such soils not only with fixed nitrogen, but also with hydrocarbon-utilizing microorganisms. Further, legume nodules may have biotechnological value as materials for cleaning oily liquid wastes.

Identification of raw materials for the production of vodkas based on the results of gas-liquid chromatographic analysis with the use of fuzzy logic

The concepts of fuzzy logic were applied to the analysis of gas-chromatographic data for 12 samples of Russian vodka products. It was found that, with the use of the truth degrees of fuzzy logic propositions on the composition of analytical samples based on a simulation of expert’s reasoning, the grade of raw materials used for the production of the analytical samples can be supposed and the conformity with standards can be established.

Alkaliphilic and halophilic hydrocarbon-utilizing bacteria from Kuwaiti coasts of the Arabian Gulf

Green animate materials from the intertidal zone of the Arabian Gulf coast accommodated more alkaliphilic and halophilic bacteria than inanimate materials. The alkaliphilic oil-utilizing bacteria, as identified by their 16S ribonucleic acid sequences, belonged to the following genera arranged in decreasing frequences: Marinobacter, Micrococcus, Dietzia, Bacillus, Oceanobacillus, and Citricoccus. The halophilic oil-utilizing bacteria belonged to the genera: Marinobacter, Georgenia, Microbacterium, Stappia, Bacillus, Isoptericola, and Cellulomonas. Most isolates could grow on a wide range of pure n-alkanes and aromatic compounds, as sole sources of carbon and energy. Quantitative gas liquid chromatographic analysis showed that individual isolates attenuated crude oil and representative pure hydrocarbons in culture. The optimum pH for most of the alkaliphilic genera was pH 10, and the optimum salinity for the halophiles ranged between 2.5 and 5% NaCl (w/v). It was concluded that as far as their microbial makeup is concerned, oily alkaline and saline intertidal areas of the Kuwaiti coasts have a self-cleaning potential.

Three novel oligosaccharides synthesized using Thermoanaerobacter brockii kojibiose phosphorylase

BackgroundRecently synthesized novel oligosaccharides have been produced primarily by hydrolases and glycosyltransferases, while phosphorylases have also been subject of few studies. Indeed, phosphorylases are expected to give good results via their reversible reaction. The purpose of this study was to synthesis other novel oligosaccharides using kojibiose phosphorylase.ResultsThree novel oligosaccharides were synthesized by glucosyltransfer from β-D-glucose 1-phosphate (β-D-G1P) to xylosylfructoside [O-α-D-xylopyranosyl-(1→2)-β-D-fructofuranoside] using Thermoanaerobacter brockii kojibiose phosphorylase. These oligosaccharides were isolated using carbon-Celite column chromatography and preparative high performance liquid chromatography. Gas liquid chromatography analysis of methyl derivatives, MALDI-TOF MS and NMR measurements were used for structural characterisation. The 1H and 13C NMR signals of each saccharide were assigned using 2D-NMR including COSY (correlated spectroscopy), HSQC (herteronuclear single quantum coherence), CH2-selected E-HSQC (CH2-selected Editing-HSQC), HSQC-TOCSY (HSQC-total correlation spectroscopy) and HMBC (heteronuclear multiple bond correlation).ConclusionThe structure of three synthesized saccharides were determined, and these oligosaccharides have been identified as O-α-D-glucopyranosyl-(1→2)-O-α-D-xylopyranosyl-(1→2)-β-D-fructofuranoside (saccharide 1), O-α-D-glucopyranosyl-(1→2)-O-α-D-glucopyranosyl-(1→2)-O-α-D-xylopyranosyl-(1→2)-β-D-fructofuranoside (saccharide 2) and O-α-D-glucopyranosyl-(1→[2-O-α-D-glucopyranosyl-1]2→2)-O-α-D-xylopyranosyl-(1→2)-β-D-fructofuranoside (saccharide 3).

Food sources of plant sterols in the EPIC Norfolk population

To investigate the intake of plant sterols and identify major dietary sources of plant sterols in the British diet. A total of 24 798 men and women recruited during 1993-1997, participating in the European Prospective Investigation into Cancer (EPIC-Norfolk). A database of the plant sterol (campesterol, beta-sitosterol, stigmasterol, campestanol and beta-sitostanol) content in foods, based on gas-liquid chromatography (GLC) analyses, was linked to nutritional intake data from food frequency questionnaires in the EPIC-Norfolk population. The mean (s.d.) intake of total plant sterols was 300 (108) mg/d for men and 293 (100) mg/d for women. Bread and other cereals, vegetables and added fats were the three major food sources of plant sterols representing 18.6 (8.9), 18.4 (8.5) and 17.3 (10.4)% of the total plant sterol intake respectively. Women had a higher plant sterol density than men (36.4 vs 32.8 mg/1000 kJ, P<0.001) and in relation to energy intake higher intakes of plant sterols from vegetables, bread and other cereals, added fats, fruits and mixed dishes (all P<0.001), whilst men had higher intakes of plant sterols from cakes, scones and chocolate, potatoes (all P<0.001) and other foods (P<0.01). The intake of plant sterols in UK, mainly from bread, cereals, fats and vegetables, is much higher than previously reported but comparable to recent European studies.

Comparison of available analytical methods to measure trans-octadecenoic acid isomeric profile and content by gas–liquid chromatography in milk fat

Accurate quantification of trans-fatty acids (TFAs) could be achieved by infrared spectroscopy or by gas–liquid chromatography (GLC). Accurate quantification by GLC should be achieved using specific highly polar capillary columns such as 100 m CP-Sil 88 or equivalent. A pre-fractionation of cis and trans-fatty acids could be performed by silver-ion thin-layer chromatography (Ag-TLC), silver-ion solid-phase extraction (Ag-SPE), or by high-performance liquid-chromatography (HPLC). A pre-fractionation step allows accurate determination of the isomeric profile but it is not essential to achieve quantification of total trans-18:1 isomers nor to determine the level of vaccenic ( trans-11 18:1) acid in dairy fat. TFA content could also be calculated in milk fat based on the TAG profile determined by GLC. In this paper, different GLC methods suitable to measure the total of trans-18:1 isomers, vaccenic acid and trans-18:1 acid isomeric distribution in milk fat were compared. Pre-separation of cis- and trans-18:1 isomers by Ag-TLC followed by GLC analysis under optimal conditions was selected as the reference method. Results obtained using alternative methods including pre-separation by HPLC followed by GLC analysis, direct quantification by GLC or calculation from the triacylglycerol (TAG) profile were compared to data acquired using the reference method. Results showed that accurate quantification of total trans-18:1 isomers and vaccenic acid could be achieved by direct quantification by GLC under optimal chromatographic conditions. This method represents a very good alternative to Ag-TLC followed by GLC analysis. On the other hand, we showed that pre-fractionation of fatty acid methyl esters (FAMEs) by HPLC represents a good alternative to Ag-TLC, even if some minor isomers are not selectively purified using this procedure.

Isolation and Identification of Novel Tri- and Tetra-saccharides Synthesized by Thermoanaerobacter brockii Kojibiose Phosphorylase

Novel tri- and tetra-saccharides were synthesized by glucosyltransfer from β-D-glucose 1-phosphate (β-D-G1P) to palatinose using Thermoanaerobacter brockii kojibiose phosphorylase. There saccharides were isolated using carbon-Celite column chromatography and preparative high performance liquid chromatography. Gas liquid chromatography analysis of methyl derivatives, MALDI-TOF MS and NMR measurements were used for structural confirmation of the saccharides. The 1H and 13C NMR signals of the saccharides were assigned using 2D-NMR including COSY, HSQC, HSQC-TOCSY and HMBC. These oligosaccharides were identified as 2G-α-D-glucopyranosyl-palatinose; O-α-D-glucopyranosyl-(1→2)-O-α-D-glucopyranosyl-(1→6)-D-fructofuranose and 2G(2-α-D-glucopyranosyl)2-palatinose; O-α-D-glucopyranosyl-(1→2)-O-α-D-glucopyranosyl-(1→2)-O-α-D-glucopyranosyl-(1→6)-D-fructofuranose.

Cholestanol metabolism in patients with cerebrotendinous xanthomatosis: absorption, turnover, and tissue deposition

To study the metabolism of cholestanol in patients with cerebrotendinous xanthomatosis (CTX), we measured the cholestanol absorption, the cholesterol and cholestanol turnover, and the tissue content of sterols in two patients. Cholestanol absorption was approximately 5.0%. The rapid exchangeable pool of cholestanol was 233 mg, and the total exchangeable pool was 752 mg. The production rate of cholestanol in pool A was 39 mg/day. [4-14C]cholestanol was detected in the xanthomas, but neither [4-14C]cholestanol nor [4-14C]cholesterol was detected in peripheral nerves biopsied at 49 and 97 days after [4-14C]cholesterol given intravenously. Of the 18 tissues analyzed at biopsy and autopsy, the cholestanol content varied from 0.09 mg/g in psoas muscle to 76 mg/g in a cerebellar xanthoma. With the assumption that the cholestanol-to-cholesterol ratio is 1.0, the relative cholestanol-to-cholesterol ratio varied from 1.0 in plasma and liver to 30.0 in the cerebellar xanthoma; cholestanol was especially high in nerve tissue. Our data indicate that CTX patients absorb cholestanol from the diet. They have a higher than normal cholestanol production rate. Cholestanol was derived from cholesterol. In CTX patients, the blood-brain barrier was intact to the passage of [4-14C]cholesterol and [4-14C]cholestanol. The deposition of large amounts of cholestanol (up to 30% of total sterols in cerebellum) in nerve tissues must have an important role in the neurological symptoms in CTX patients. In view of the intact blood-brain barrier, several other explanations for the large amounts of cholestanol in the brain were postulated.