Cholesterol Articles and Abstracts

For medical practitioners and the general public - Cholesterol Journal Article Catalog.

Cholesterol Journal Articles



Record 10441 to 10460
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Raloxifene (LY139481 HCI) prevents bone loss and reduces serum cholesterol without causing uterine hypertrophy in ovariectomized rats
Black, L. J., M. Sato, et al. (1994), J Clin Invest 93(1): 63-9.
Abstract: There is a medical need for an agent with the positive effects of estrogen on bone and the cardiovascular system, but without the negative effects on reproductive tissue. Raloxifene (LY139481 HCI) is a benzothiophene derivative that binds to the estrogen receptor and inhibits the effects of estrogen on the uterus. In an ovariectomized (OVX) rat model we investigated the effects of raloxifene on bone loss (induced by estrogen deficiency), serum lipids, and uterine tissue. After oral administration of raloxifene for 5 wk (0.1-10 mg/kg per d) to OVX rats, bone mineral density in the distal femur and proximal tibia was significantly greater than that observed in OVX controls (ED50 of 0.03-0.3 mg/kg). Serum cholesterol was lower in the raloxifene-treated animals, which had a minimal effective dose of 0.1 mg/kg and an approximate oral ED50 of 0.2 mg/kg. The effects of raloxifene on bone and serum cholesterol were comparable to those of a 0.1-mg/kg per d oral dose of ethynyl estradiol. Raloxifene diverged dramatically from estrogen in its lack of significant estrogenic effects on uterine tissue. Ethynyl estradiol produced a marked elevation in a number of uterine histologic parameters (e.g., epithelial cell height, stromal eosinophilia). These data suggest that raloxifene has promise as an agent with beneficial bone and cardiovascular effects in the absence of significant uterine effects.

Raloxifene and estrogen reduces progression of advanced atherosclerosis--a study in ovariectomized, cholesterol-fed rabbits
Bjarnason, N. H., J. Haarbo, et al. (2001), Atherosclerosis 154(1): 97-102.
Abstract: The present study investigated the effect of raloxifene, a selective estrogen receptor modulator (SERM), on aortic atherosclerosis in 80 ovariectomized, cholesterol-fed rabbits with pre-induced atherosclerosis. The animals were fed an atherogenic diet containing 240 mg cholesterol/day for 15 weeks, after this period a baseline control group was sacrificed. Thereafter, oral treatment was initiated with either estradiol 4 mg/day (n=20), raloxifene (210 mg/day) or placebo (n=20). In the treatment period of 39 weeks, the dietary cholesterol content was reduced to 80 mg cholesterol/day. Postmortem evaluation showed a significantly increased uterine weight induced by estradiol treatment (10.3+/-1.2 g), whereas raloxifene intervention caused a decreased uterus weight (1.21+/-0.1 g) when compared to placebo (2.48+/-0.47 g). Throughout the study, serum lipids increased in all groups to levels seen in very high risk humans. After 58 weeks the cholesterol content in the aorta was 3.18+/-0.54 micromol/cm(2) (38% reduction) in the estradiol group, 3.66+/-0.52 micromol/cm(2) (29% reduction) in the raloxifene group and 5.12+/-0.60 micromol/cm(2) in the placebo group. Analyses of the aortic cholesterol content corrected for time-averaged serum cholesterol revealed that both estradiol and raloxifene therapy significantly reduced the progression of atherosclerosis (P<0.01 for both) as compared to placebo.

Raloxifene inhibits aortic accumulation of cholesterol in ovariectomized, cholesterol-fed rabbits
Bjarnason, N. H., J. Haarbo, et al. (1997), Circulation 96(6): 1964-9.
Abstract: BACKGROUND: The beneficial effect of long-term hormone replacement therapy in terms of a decreased risk of cardiovascular disease is now generally accepted. Raloxifene, a selective estrogen receptor modulator, has demonstrated hypolipidemic properties while leaving the endometrium unstimulated. METHODS AND RESULTS: For our study of the effects of raloxifene on atherosclerosis, 75 rabbits were ovariectomized and treated with either raloxifene, 17beta-estradiol, or placebo; 25 rabbits were sham operated and treated with placebo. After 45 weeks, the raloxifene group had two thirds of the aortic atherosclerosis, as evaluated by the cholesterol content of the proximal inner part of the aorta, found in the placebo group (placebo, 577+/-55.1 nmol/mg protein; raloxifene, 397+/-53.6 nmol/mg protein; P<.05); the estrogen group had one third of the aortic atherosclerosis in the placebo group (estrogen, 177+/-32.1 nmol/mg protein; P<.001). The sham-operated group (473+/-59.6 nmol/mg protein) was not significantly different from placebo. These effects were only partly explained by the changes in serum lipids and lipoproteins, and treatment with both estrogen and raloxifene independently predicted the response in aorta cholesterol. Because plasma levels of total raloxifene were low relative to clinical values in postmenopausal women, dose-response data for raloxifene are required. CONCLUSIONS: Our findings indicate that raloxifene hydrochloride has a potentially important antiatherogenic effect, analogous to that observed with estrogen in this model.

Raloxifene inhibits cholesterol aortic content but not atherosclerotic plaque size in oophorectomised cholesterol-fed rabbits
Castelo-Branco, C., A. Sanjuan, et al. (2004), J Obstet Gynaecol 24(1): 47-51.
Abstract: Raloxifene, a selective oestrogen receptor modulator, is effective in the treatment of osteoporosis without stimulating the breast and the endometrium. Although it is associated with a decrease of cardiovascular risk markers the effect of these changes on atherogenesis, is not clear. In this study, we aimed to investigate the effect of raloxifene on aorta atherogenesis. A total of 32 cholesterol-fed New Zealand white rabbits were studied for 4 months. Twenty-four rabbits underwent bilateral ovariectomy; of these eight received raloxifene (group OR), eight received oestradiol valerate (group OE) and eight received placebo after sterilisation (group OP). Finally, another eight were sham-operated (non-ovariectomised) and received placebo with a hypercholesterolaemic diet (group SP). After the diet, total levels of cholesterol increased in group SP from 111.25 +/- 34.8 mg/dl to 1112.25 +/- 364.2, in group OP from 122.62 +/- 27.7 mg/dl to 1367.37 +/- 348.4, in group OE from 65.25 +/- 17.01 to 1710.5 +/- 356.2 and in group OR from 108.88 +/- 15.54 mg/dl to 1407.86 +/- 397.7 (no significant differences). At 4 months, in both treated and untreated rabbits, the cholesterol-rich diet caused atherosclerotic lesions affecting 24.51 +/- 16.1% for group SP, 30.47 +/- 12.2% for group OP, 30.31 +/- 18.07% for group OR and 17.91 +/- 10.19 for group OE (P<0.05) of the aortic surface, respectively. Aortic cholesterol expressed as mg of cholesterol/mg aortic weight was found to decrease in raloxifene-treated rabbits: 3.82 +/- 2.14 mg col/aortic mg versus 8.55 +/- 4.63 (group OP) and 11.97 +/- 11.33 (group SP). P<0.001. Raloxifene reduced aortic cholesterol content but not the atherosclerotic plaque extension in cholesterol-fed ovariectomised rabbits.

Raloxifene reduces atherosclerosis: studies of optimized raloxifene doses in ovariectomized, cholesterol-fed rabbits
Bjarnason, N. H., J. Haarbo, et al. (2000), Clin Endocrinol (Oxf) 52(2): 225-33.
Abstract: OBJECTIVE: We have previously shown that raloxifene, a selective oestrogen receptor modulator, 35 mg/day inhibits atherosclerosis in ovariectomized, cholesterol-fed rabbits. This effect was only partial as compared to 17beta-oestradiol 4 mg/day; however, plasma raloxifene concentrations were low relative to those obtained in raloxifene-treated women. We therefore investigate the effects of raloxifene at higher doses. DESIGN: The study on atherosclerosis in ovariectomized, cholesterol-fed rabbits (n = 80) compared raloxifene 70 mg/day and 210 mg/day to 17beta-oestradiol 4 mg/day and placebo. RESULTS: After 48 weeks of therapy, the aortic cholesterol content in the 70 mg/day and 210 mg/day raloxifene treatment groups were 471 +/- 56 nmol/mg protein and 456 +/- 56 nmol/mg protein, respectively. This was significantly less than in the placebo group (654 +/- 69 nmol/mg protein; P < 0.05). In the oestrogen-treated group, the aortic cholesterol content was 357 +/- 62 nmol/mg protein (P < 0.01 as compared to placebo). Differences in serum lipids between the treatment groups could only partly explain the effect on aortic cholesterol content, indicating that additional anti-atherogenic mechanisms may contribute to the decrease in aortic atherosclerosis. This anti-atherosclerotic activity of raloxifene was observed at plasma concentrations comparable to those in postmenopausal women during raloxifene treatment. CONCLUSIONS: We conclude that clinically relevant raloxifene treatment inhibits aortic atherosclerosis in ovariectomized, cholesterol-fed rabbits.

Raman microspectroscopy of intracellular cholesterol crystals in cultured bovine coronary artery endothelial cells
Hawi, S. R., K. Nithipatikom, et al. (1997), J Lipid Res 38(8): 1591-7.
Abstract: Raman microspectroscopy is presented as a promising technique for the in situ characterization of intracellular cholesterol crystals. Crystal characterization is the first step in investigating the effects of various stimuli on their formation and in determining their role in the development of atherosclerosis. Treatment of cultured bovine coronary artery endothelial cells with 22-hydroxycholesterol (220HC) stimulated the production of intracellular crystals, a phenomenon that did not occur in the absence of viable cells. These crystals were identified as a combination of the 220HC starting material and cholesterol. The best fit to the average Raman spectrum of the microscopic crystals was achieved with a combination of 70% Raman contribution from 220HC and 30% from cholesterol. GC/MS analysis of the crystals confirmed the presence of both compounds. These results demonstrate the potential of Raman microspectroscopy as a powerful tool in lipid research, particularly for the in situ characterization of intracellular crystals.

Raman spectroscopy for quantifying cholesterol in intact coronary artery wall
Romer, T. J., J. F. Brennan, 3rd, et al. (1998), Atherosclerosis 141(1): 117-24.
Abstract: The chemical composition of vascular lesions, an important determinant of plaque progression and rupture, can not presently be determined in vivo. Prior studies have shown that Raman spectroscopy can accurately quantify the amounts of major lipid classes and calcium salts in homogenized coronary artery tissue. This study determines how the relative cholesterol content, which is calculated from Raman spectra collected at the luminal surface of an artery, is related to its depth in an intact arterial wall. Raman spectra of human atherosclerotic plaques were measured after thin tissue layers were successively placed on them. From these spectra, relative cholesterol contents were calculated and used to determine how cholesterol signal strength is attenuated by overlaying tissue. Then, intact artery samples (n = 13) were examined spectroscopically, sectioned and stained specifically for cholesterol. Images of these sections were digitized, and image intensities were related to cholesterol content. These cholesterol amounts were weighed appropriately for depth into the tissue and area-integrated for comparison with spectroscopy results. A decaying exponential curve was fit to the layer study data (r2 = 0.97) and showed that approximately 300 microm of tissue attenuates cholesterol signals by 50%. In intact plaques, the spectroscopically-determined cholesterol amounts correlated strongly and linearly with those determined by digital microscopy (r2 = 0.94). With Raman spectroscopy techniques, the cholesterol content of a lesion can be determined by properly accounting for its depth into an arterial wall. Our results suggest that chemical concentrations in an artery wall could be mapped throughout its thickness, possibly by combining Raman spectroscopy methods with other techniques.

Ramatroban, a thromboxane A2 receptor antagonist, prevents macrophage accumulation and neointimal formation after balloon arterial injury in cholesterol-fed rabbits
Ishizuka, T., K. Matsumura, et al. (2003), J Cardiovasc Pharmacol 41(4): 571-8.
Abstract: Macrophage infiltration appears to play an important role in restenosis after arterial intervention. Monocyte chemoattractant protein-1 (MCP-1) is a major chemotactic factor for macrophages. We have previously shown that ramatroban, a thromboxane A(2) (TXA(2)) receptor antagonist, diminished the expression of MCP-1 in human vascular endothelial cells. The aim of this study was to evaluate whether, after balloon angioplasty of atherosclerotic arteries, ramatroban would reduce MCP-1 expression, macrophage accumulation, and neointimal formation. New Zealand white rabbits were fed a cholesterol-rich diet for 4 weeks, and the abdominal aorta of the rabbits were injured by a 2-French Fogarty catheter. They were randomized to receive 1 or 5 mg/kg daily of ramatroban (n = 7 or n = 8) or saline (n = 6). At 4 weeks after balloon angioplasty, the intimal hyperplasia and the macrophage-positive area in the intima by the ramatroban treatment was significantly reduced. Monocyte chemoattractant protein-1 gene expression in injured aortas of the ramatroban-treated group was significantly less evident than in the vehicle-treated group. Thromboxane A(2) receptor blockade by ramatroban for 4 weeks after balloon angioplasty in the atherosclerotic rabbits prevented macrophage infiltration through MCP-1 downregulation and neointimal formation.

Randomised controlled trial in northern England of the effect of a person knowing their own serum cholesterol concentration
Elton, P. J., A. Ryman, et al. (1994), J Epidemiol Community Health 48(1): 22-5.
Abstract: SUBJECT OBJECTIVE--To test the hypotheses that the knowledge that the serum cholesterol concentration is raised (> or = 6.5 mmol/l) will lead to a reduction in the concentration after education intervention and that the knowledge that the concentration is not raised does not lead to an increase in the serum cholesterol concentration after education intervention. DESIGN--Prospective randomised trial, with investigators blind to the randomisation. SETTING--An industrial site in Manchester, England. PARTICIPANTS--A total of 495 employees of Imperial Chemical Industries, 469 of whom completed the trial. MAIN RESULT--There was a significant reduction in the serum cholesterol concentration of those whose initial concentration was > or = 6.5 mmol/l and who were given the result. This reduction was 0.28 mmol/l greater than in the control group. The reduction was similar, however, to the increase in the serum cholesterol concentration in those whose initial concentration was < 5.2 mmol/l, regardless of whether or not they had been given the result. CONCLUSION--These results support the hypotheses, although the lack of regression to the mean in the control group with high serum cholesterol suggests that this conclusion should be treated with caution.

Randomised placebo controlled trial of effect on mood of lowering cholesterol concentration. Oxford Cholesterol Study Group
Wardle, J., J. Armitage, et al. (1996), Bmj 313(7049): 75-8.
Abstract: OBJECTIVE--To evaluate the effects on mood of a substantial and prolonged reduction in total cholesterol concentration. DESIGN--Randomised placebo controlled comparison of patients who had been allocated to receive simvastatin 20 mg or 40 mg daily versus those allocated matching placebo in a ratio of 2:1. Follow up at an average of 152 weeks after randomisation. SUBJECTS--Men and women aged between 40 and 75 years at entry with blood total cholesterol of 3.5 mmol/l or greater, who were considered to be at higher than average risk of coronary heart disease based on medical history. MAIN OUTCOME MEASURES--The shortened profile of mood states questionnaire, reported use of psychotropic medication, and symptoms possibly related to mood. RESULTS--Simvastatin reduced total cholesterol by 1.9 mmol/l (26.7%) at the time of follow up. Among all 621 patients randomised to simvastatin (414 patients) or placebo (207 patients) there were no significant differences in the use of psychotropic medication or in reports of symptoms possibly related to mood. Of these patients, 491 (334 simvastatin, 157 placebo) completed the mood questionnaire, and there were no significant differences between the treatment groups in total or subscale scores, even when patients with low baseline cholesterol concentrations or elderly subjects were considered separately. CONCLUSION--These results do not support the hypothesis that treatment to lower cholesterol concentration causes mood disturbance.

Randomized crossover study of effect of resistance training on glycemic control, muscular strength, and cholesterol in type I diabetic men
Durak, E. P., L. Jovanovic-Peterson, et al. (1990), Diabetes Care 13(10): 1039-43.
Abstract: The goal of this study was to evaluate a program of resistance weight training on cardiovascular risk factors, blood glucose management, and overall strength in diabetic subjects. A randomized crossover design was performed on eight male type I (insulin-dependent) diabetic subjects (mean +/- SD age 31 +/- 3.5 yr, height 176 +/- 5.6 cm, body wt 80 +/- 15 kg, duration of diabetes 12.3 +/- 9.8 yr, and insulin dose 24 U NPH/day and 21 U regular/day). The program consisted of heavy-resistance weight training 3 days/wk for 10 wk, concentrating on the strengthening of major muscle groups through progressive resistance. Blood tests included total cholesterol, triglycerides, very-low-density lipoprotein and high-density lipoprotein cholesterol, and HbA1c. These tests were repeated at three time points during the program. Field-strength testing was performed before and after training. An improvement was seen in the squat (93.6% increase, P less than 0.0001) and bench press (58% increase, P less than 0.005). HbA1c and triglyceride levels showed no change during the resting portion of the experiment but showed a significant change with the training program: HbA1c 6.9 +/- 1.4 vs 5.8 +/- 0.9% (P = 0.05) and triglyceride 5.044 +/- 1.06 vs. 4.628 +/- 0.88 mM (P = 0.01). Self-monitored glucose (taken pre- and postexercise) showed a decrease from 7.85 +/- 3.13 to 7.05 +/- 2.91 mM (P = 0.0001). Very-low-density lipoprotein cholesterol and triglycerides did not change after training. Analysis of variance showed no significant differences over time from the three time points with regard to reductions in cardiovascular risk factors or HbA1c.(ABSTRACT TRUNCATED AT 250 WORDS)

Range of serum cholesterol values in the population developing coronary artery disease
Kannel, W. B. (1995), Am J Cardiol 76(9): 69C-77C.
Abstract: Blood lipids have been established as fundamental to atherogenesis, and there is a better understanding of the pathogenesis of atherosclerosis and of the various pharmacologic agents available to counter the mechanisms involved. However, more optimal lipid levels must be established for treatment of both the healthy population and persons already with coronary artery disease (CAD). In the Framingham Study cohort, those with elevated serum total cholesterol (> 275 mg/dl) had an increased risk of adverse outcomes whether healthy or with CAD. Compared with persons with cholesterol levels < 200 mg/dl (< 5.17 mmol/liter), the risk ratios for patients with elevated cholesterol levels were 3.8 for reinfarction, 2.6 for CAD mortality, and 1.9 for overall mortality. The prevalence of cholesterol levels > or = 240 mg/dl (> or = 6.21 mmol/liter) in persons who had sustained myocardial infarction was 35-52% in men and 66% in women, but 20% of myocardial infarctions occurred in people who had cholesterol levels < 200 mg/dl (< 5.17 mmol/liter). The average levels of serum total cholesterol and low density lipoprotein (LDL) cholesterol (225 mg/dl 5.82 mmol/liter and 150 mg/dl 3.88 mmol/liter, respectively) at which CAD events occurred in men were below the levels recommended for treatment according to the guidelines of the National Cholesterol Education Program. In women, these levels were only slightly above the guideline levels. The average cholesterol levels at which CAD events occurred were substantially higher in women and decreased with age. Also, a steady decline in the average cholesterol levels of patients over the decades reflected chiefly the aging of the cohort.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapamycin attenuates atherosclerosis induced by dietary cholesterol in apolipoprotein-deficient mice through a p27 Kip1 -independent pathway
Castro, C., J. M. Campistol, et al. (2004), Atherosclerosis 172(1): 31-8.
Abstract: Activation of immune cells and dysregulated growth and motility of vascular smooth muscle cells contribute to neointimal lesion development during the pathogenesis of vascular obstructive disease. Inhibition of these processes by the immunosuppressant rapamycin is associated with reduced neointimal thickening in the setting of balloon angioplasty and chronic graft vessel disease (CGVD). In this study, we show that rapamycin elicits a marked reduction of aortic atherosclerosis in apolipoprotein E (apoE)-null mice fed a high-fat diet despite sustained hypercholesterolemia. This inhibitory effect of rapamycin coincided with diminished aortic expression of the positive cell cycle regulatory proteins proliferating cell nuclear antigen and cyclin-dependent kinase 2. Moreover, rapamycin prevented the normal upregulation of the proatherogenic monocyte chemoattractant protein-1 (MCP-1, CCL2) seen in the aorta of fat-fed mice. Previous studies have implicated the growth suppressor p27(Kip1) in the antiproliferative and antimigratory activities of rapamycin in vitro. However, our studies with fat-fed mice doubly deficient for p27(Kip1) and apoE disclosed an antiatherogenic effect of rapamycin comparable with that found in apoE-null mice with an intact p27(Kip1) gene. Taken together, these findings extend the therapeutic application of rapamycin from the restenosis and CGVD models to the setting of diet-induced atherosclerosis. Our results suggest that rapamycin-dependent atheroprotection occurs through a p27(Kip1)-independent pathway that involves reduced expression of positive cell cycle regulators and MCP-1 within the arterial wall.

Rapid analysis of cholesterol-elevating compounds in coffee brews by off-line high-performance liquid chromatography/high-resolution gas chromatography
Ruiz del Castillo, M. L., M. Herraiz, et al. (1999), J Agric Food Chem 47(4): 1525-9.
Abstract: A new method is proposed to analyze the cholesterol-elevating cafestol and kahweol which allows their rapid and reliable determination in different coffee brews. The method involves the preseparation of the sample by high-performance liquid chromatography, the collection of the selected fraction, and its subsequent analysis by high-resolution gas chromatography using a programmed temperature vaporizer operated in the split mode as sampling system. Under the experimental conditions investigated, recoveries as high as 87% (cafestol) and 94% (kahweol) were achieved while detection limits equal to 0.06 and 0.04 ppm for cafestol and kahweol, respectively, were obtained. Examples are given comparing levels of cafestol and kahweol resulting from the same ground roasted coffee by different brewing methods, which show the lowest values for brews prepared from coffee bags.

Rapid and simple method for determination of cholesterol in processed food
Naeemi, E. D., N. Ahmad, et al. (1995), J AOAC Int 78(6): 1522-5.
Abstract: An improved method for determination of cholesterol in processed food with only one extraction and without solvent removal was developed. Total time to analyze a sample including gas chromatographic (GC) analysis is 45 min. Food samples spiked with internal standard are hydrolyzed in a screw-capped vial with saturated methanolic KOH. Cyclohexane is added to the mixture, and the upper layer is analyzed by GC on a capillary column. Average recoveries of spiked white eggs are 99 +/- 0.5%. Fifteen types of processed food containing shrimp, fish, meat, cheese, eggs, and vegetables were analyzed with this method and with the AOAC method.

Rapid and simple method for measurement of the cholesterol content of gallstones
Kazmierczak, S. C., J. Cole, et al. (1993), J Clin Lab Anal 7(3): 139-40.

Rapid cholesterol nucleation time and cholesterol gall stone formation after subtotal or total colectomy in humans
Makino, I., K. Chijiiwa, et al. (1994), Gut 35(12): 1760-4.
Abstract: Changes in biliary lipid composition, pH, ionised calcium, total and unconjugated bilirubin, and cholesterol nucleation time of gall bladder bile samples were examined in six patients who had undergone subtotal or total colectomy between five months and seven years previously, and values were compared with those in control patients with no gall stones. The colectomy group mainly comprised patients with ulcerative colitis and familial adenomatosis coli, in whom only a short length of the terminal ileum (mean (SEM) 2.25 (0.57) cm) had been resected. The reconstruction procedures were ileoanal anastomosis in two patients, terminal ileostomy in two, ileorectal anastomosis in one, and J shaped ileal pouch-anal anastomosis in one patient. The distributions of age, sex, and relative body weight were similar in the two groups. The gall bladder bile was lithogenic in the post colectomy group--these patients had a significantly increased cholesterol saturation index (p < 0.01) and rapid cholesterol nucleation time (p < 0.05) compared with the control group. A significant increase in the molar percentage of cholesterol and a decrease in that of total bile acid associated with significantly decreased secondary bile acids (p < 0.05) were observed in the post colectomy group. Gall stones formed in two of six patients after colectomy were cholesterol stones containing more than 80% cholesterol by dry weight. Total and unconjugated bilirubin, pH, and ionised calcium values were similar in the two groups. The results indicate that after total or subtotal colectomy the composition of gall bladder bile increases the risk of cholesterol gall stone formation.

Rapid decrease of serum cholesterol concentration and postpartum depression
Ploeckinger, B., K. Dantendorfer, et al. (1996), Bmj 313(7058): 664.

Rapid determination of cholesterol in milk and milk products by direct saponification and capillary gas chromatography
Fletouris, D. J., N. A. Botsoglou, et al. (1998), J Dairy Sci 81(11): 2833-40.
Abstract: A simple method is described for the determination of cholesterol in milk and milk products. Samples (0.2 g) are saponified in capped tubes with 0.5 M methanolic KOH solution by heating for 15 min at 80 degrees C. Water is added to the mixtures, and the unsaponifiable fractions are extracted with hexane to be further analyzed by capillary gas chromatography. Because of the rapid sample preparation and gas chromatographic procedures, a single sample can be analyzed in 30 min. Overall recovery was 98.6%, and the linearity was excellent for the fortification range examined. Precision data that were based on the variation within and between days suggested an overall relative standard deviation value of 1.4%. The method has been successfully applied to quantitate cholesterol in a variety of milk products.

Rapid determination of cholesterol in single and multicomponent prepared foods
al-Hasani, S. M., J. Hlavac, et al. (1993), J AOAC Int 76(4): 902-6.
Abstract: A rapid method has been developed for cholesterol determination in single and multicomponent foods. The method involves alcoholic KOH saponification of the samples, extraction of the nonsaponifiable fraction with hexane, and injection of concentrated extract into the gas chromatograph without derivatizations. It has been applied to a wide variety of frozen and refrigerated foods. More than 300 samples were analyzed with a coefficient of variation (CV) ranging from 0.5 to 8.6%. The average recoveries of cholesterol from spiked oil and tomato vegetable soup samples were 100 +/- 1.5% and 99.7 +/- 1.6% and the CVs were 1.5 and 1.6%, respectively. This method reduces labor by > 70%, eliminates dangerous chemicals, and minimizes solvent use, compared to the AOAC method and other methods cited in the manuscript. The method was used successfully on a wide variety of multicomponent foods. We recommend this method for collaborative study under the AOAC guidelines for method approval.


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