Sterol composition of shellfish species commonly consumed in the United States

Abstract

BackgroundShellfish can be a component of a healthy diet due to a low fat and high protein content, but the cholesterol content of some species is often cited as a reason to limit their consumption. Data on levels of non-cholesterol sterols in commonly consumed species are lacking.ObjectiveShellfish were sampled and analyzed to update sterol data in the United States Department of Agriculture (USDA) National Nutrient Database for Standard Reference.DesignUsing a nationwide sampling plan, raw shrimp and sea scallops, canned clams, and steamed oysters, blue crab, and lobster were sampled from 12 statistically selected supermarkets across the United States in 2007–08. For each species, four composites were analyzed, each comprised of samples from three locations; shrimp and scallops from six single locations were also analyzed separately. Using validated analytical methodology, 14 sterols were determined in total lipid extracts after saponification and derivatization to trimethylsilyethers, using gas chromatography for quantitation and mass spectrometry for confirmation of components.ResultsCrab, lobster, and shrimp contained significant cholesterol (96.2–27 mg/100 g); scallops and clams had the lowest concentrations (23.4–30.1 mg/100 g). Variability in cholesterol among single-location samples of shrimp was low. The major sterols in the mollusks were brassicasterol (12.6–45.6 mg/100 g) and 24-methylenecholesterol (16.7–41.9 mg/100 g), with the highest concentrations in oysters. Total non-cholesterol sterols were 46.5–75.6 mg/100 g in five single-location scallops samples, but 107 mg/100 g in the sixth, with cholesterol also higher in that sample. Other prominent non-cholesterol sterols in mollusks were 22-dehydrocholesterol, isofucosterol, clionasterol, campesterol, and 24-norcholesta-5,22-diene-3β-ol (4–21 mg/100 g).ConclusionsThe presence of a wide range of sterols, including isomeric forms, in shellfish makes the analysis and quantitation of sterols in marine species more complex than in animal and plant tissues. The detailed sterol composition reported herein provides data that may be useful in research on the impact of shellfish consumption on dietary risk factors.

Changes in lipids of shrimp (Acetes vulgaris) during salting and fermentation

“…The presence of ST was in agreement with those reported for other shrimp species such as Penaeus Semisulcatus [27], Orconectes limosus [28], and Penaeus stylirrostris [29]. Free sterols are commonly found in developing ovaries, where they contribute to membrane structure and form precursors for hormones, steroids as well as fat-soluble vitamins [30]. For the crustaceans, the predominant sterol was cholesterol with only minor amounts of other sterols.…”

“…For the crustaceans, the predominant sterol was cholesterol with only minor amounts of other sterols. A high ratio of cholesterol/non‐cholesterol sterols was observed in crustaceans . Normally, crustaceans contain cholesterol at relatively high levels, compared to meats .…”

“…A high ratio of cholesterol/non‐cholesterol sterols was observed in crustaceans . Normally, crustaceans contain cholesterol at relatively high levels, compared to meats . Cholesterol is an essential nutrient for crustaceans since they are incapable of de novo synthesis of the steroid ring .…”

“…Normally, crustaceans contain cholesterol at relatively high levels, compared to meats [31]. Cholesterol is an essential nutrient for crustaceans since they are incapable of de novo synthesis of the steroid ring [30]. In contrast to cholesterol, PLs, TAGs, and DGs are synthesized by crustacean tissues [32].…”

Chemical Profiling and Bioactivity of Body Wall Lipids from Strongylocentrotus droebachiensis

“…BW lipid extract contained mainly cholesterol (50 μg/mg) ( Figure 1 and Table 2 ). Minor non-cholesterol sterols included desmosterol, campesterol, stigmasterol, and clionasterol (gamma-sitosterol) which is a common constituent in oyster, for example [ 19 ]. For GC-MS analyses from abundant AOG sources, purified samples from unsaponifiable fraction have been used.…”