Fatty acids composition of the most common bivalves in Korean diet

Consumption of bivalve molluscs, such as oysters, mussels, clams and scallops, makes a significant part of the daily Korean diet. Bivalves provide high quality proteins with all the dietary-essential amino acids, lipids, vitamins, minerals and other bioactive nutrients, which offer a variety of health benefits to the consumer [1]. This food contains less than 5 percent of total fat, so it is considered a low-fat food. Beside the amount of total fat, the proportions of saturated, monounsaturated and polyunsaturated fatty acids (FA) (S, M and P, respectively), as well as ratio of n-3 (ω-3) and n-6 (ω-6) P in food are very important for the health diet [2]. Fourteen species of bivalves Anadara broughtonii (AB), Ruditapes philippinarum (Manila clam (RP)), Tegillarca granosa (TG), Pecten yessoensis (Yesso scallop (YS), Argopecten spp. (small scallop (SS), Chlamys farreri farreri (CF), Cyclina sinensis (CS), Leukoma jedoensis (LJ), Mytilus califorianus (MCa) Mytilus galloprovancialis (MG), Maretrix lusoria (ML), Mactra quadrangularis (MQ), Sinovacula constricta (SC) and Crassostrea gigas (Pacific oyster (PC)) were bought in two fish markets in Incheon, Korea, in order to determine FA composition using GC/EI-MS of fatty acid methyl esters (FAME). The FAME were identified by comparing their retention times with those of the FAME standards or by comparing their mass spectra with those stored in the NIST Mass Spectral Library. In the bivalve samples, 43 different FA were identified, of which 10 were S, 12 M and 13 P, other FA were 7 methyl-FA and 1 hydroxyl-FA. The P/S ratio and ω-6/ω-3 P ratio are the most significant markers of lipid composition in a healthy diet and both should be close to 1 [3]. Among analysed species, only YS and SS have P/S ratio close to 1 (1,20 and 1.16, respectively), while other species have value between 0.07 and 0.73. The obtained values for ω-6/ω-3 P ratio were from 0.008 to 0.55, which indicates that bivalve molluscs are the valuable source of ω-3 P (EPA and DHA). These ω-3 P play important roles in growth, development, and maintenance of health

Fatty acids composition of the most common bivalves in Korean diet

Consumption of bivalve molluscs, such as oysters, mussels, clams and scallops, makes a significant part of the daily Korean diet. Bivalves provide high quality proteins with all the dietary-essential amino acids, lipids, vitamins, minerals and other bioactive nutrients, which offer a variety of health benefits to the consumer [1]. This food contains less than 5 percent of total fat, so it is considered a low-fat food. Beside the amount of total fat, the proportions of saturated, monounsaturated and polyunsaturated fatty acids (FA) (S, M and P, respectively), as well as ratio of n-3 (ω-3) and n-6 (ω-6) P in food are very important for the health diet [2]. Fourteen species of bivalves Anadara broughtonii (AB), Ruditapes philippinarum (Manila clam (RP)), Tegillarca granosa (TG), Pecten yessoensis (Yesso scallop (YS), Argopecten spp. (small scallop (SS), Chlamys farreri farreri (CF), Cyclina sinensis (CS), Leukoma jedoensis (LJ), Mytilus califorianus (MCa) Mytilus galloprovancialis (MG), Maretrix lusoria (ML), Mactra quadrangularis (MQ), Sinovacula constricta (SC) and Crassostrea gigas (Pacific oyster (PC)) were bought in two fish markets in Incheon, Korea, in order to determine FA composition using GC/EI-MS of fatty acid methyl esters (FAME). The FAME were identified by comparing their retention times with those of the FAME standards or by comparing their mass spectra with those stored in the NIST Mass Spectral Library. In the bivalve samples, 43 different FA were identified, of which 10 were S, 12 M and 13 P, other FA were 7 methyl-FA and 1 hydroxyl-FA. The P/S ratio and ω-6/ω-3 P ratio are the most significant markers of lipid composition in a healthy diet and both should be close to 1 [3]. Among analysed species, only YS and SS have P/S ratio close to 1 (1,20 and 1.16, respectively), while other species have value between 0.07 and 0.73. The obtained values for ω-6/ω-3 P ratio were from 0.008 to 0.55, which indicates that bivalve molluscs are the valuable source of ω-3 P (EPA and DHA). These ω-3 P play important roles in growth, development, and maintenance of health

Study of element contents in bivalve molluscs: health benefit and risk

Bivalve molluscs, which include mussels, oysters and clams, have high nutritional value. They are regarded as a good source for proteins, lipids, carbohydrates and minerals [1]. On the other hand, seafood may also contain harmful contaminants and other undesirable substances such as mercury and persistent halogenated compounds, which has resulted in a number of risk-benefit assessments during the last decade [2]. Four species of bivalve molluscs Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) and Anadara broughtonii (AB) were bought in two fish markets in Incheon, Korea, in order to determine content of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se, Zn, and Fe and consequently, to estimate the health hazards associated to dietary intake. The samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after closed-vessel microwave digestion. The analytical accuracy of the method was evaluated by using the SRM (TORT-2, lobster hepatopancreas). Application of principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a tendency to form three groups between samples belonging to different genus of samples. European food safety authority (EFSA) has established recommended daily intake (RDI) values for Cu, Fe, Mn and Zn of 3, 14, 5 and 10 mg/day, respectively. We calculated the RDI for daily consumption in milligrams per 300 g of sample. Our results showed that these species could serve as a good dietary source of essential elements, especially Fe, Mn and Zn. However, all species showed As content higher than the maximum tolerable limit specified by EFSA. Seafood is the major contributor to As in the diet though As in seafood mostly occurs as organic As species [3]. In addition, content of Mn in Yesso scallop is few times higher than in other species

Alpha-Gal on the Protein Surface Hampers Transcytosis through the Caco-2 Monolayer

Transepithelial transport of proteins is an important step in the immune response to food allergens. Mammalian meat allergy is characterized by an IgE response against the carbohydrate moiety galactosyl-α-1,3-galactose (α-Gal) present on mammalian glycoproteins and glycolipids, which causes severe allergic reactions several hours after red meat consumption. The delayed reaction may be related to the processing of α-Gal carrying proteins in the gastrointestinal tract. The aim of this study was to investigate how protein glycosylation by α-Gal affects the susceptibility to gastric digestion and transport through the Caco-2 cell monolayer. We found that α-Gal glycosylation altered protein susceptibility to gastric digestion, where large protein fragments bearing the α-Gal epitope remained for up to 2 h of digestion. Furthermore, α-Gal glycosylation of the protein hampered transcytosis of the protein through the Caco-2 monolayer. α-Gal epitope on the intact protein could be detected in the endosomal fraction obtained by differential centrifugation of Caco-2 cell lysates. Furthermore, the level of galectin-3 in Caco-2 cells was not affected by the presence of α-Gal glycosylated BSA (bovine serum albumin) (BSA-α-Gal). Taken together, our data add new knowledge and shed light on the digestion and transport of α-Gal glycosylated proteins

The chemical characterization of Nigerian propolis samples and their activity against Trypanosoma brucei.

Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b.brucei with the highest activity being in the samples from Southern Nigeria. The more active samples were fractionated in order to isolate the component(s) responsible for their activity using medium pressure liquid chromatography (MPLC). Three xanthones, 1,3,7-trihydroxy-2,8-di-(3-methylbut-2-enyl)xanthone, 1,3,7-trihydroxy-4,8-di-(3-methylbut-2-enyl)xanthone a previously undescribed xanthone and three triterpenes: ambonic acid, mangiferonic acid and a mixture of α-amyrin with mangiferonic acid (1:3) were isolated and characterised by NMR and LC-MS. These compounds all displayed strong inhibitory activity against T.b.brucei but none of them had higher activity than the crude extracts. Partial least squares (PLS) modelling of the anti-trypanosomal activity of the sample extracts using the LC-MS data indicated that high activity in the extracts, as judged from LCMS 2data, could be correlated to denticulatain isomers in the extracts

Sandwich ELISA for the Quantification of Nucleocapsid Protein of SARS-CoV-2 Based on Polyclonal Antibodies from Two Different Species

In this study, a cost-effective sandwich ELISA test, based on polyclonal antibodies, for routine quantification SARS-CoV-2 nucleocapsid (N) protein was developed. The recombinant N protein was produced and used for the production of mice and rabbit antisera. Polyclonal N protein-specific antibodies served as capture and detection antibodies. The prototype ELISA has LOD 0.93 ng/mL and LOQ 5.3 ng/mL, with a linear range of 1.52–48.83 ng/mL. N protein heat pretreatment (56 °C, 1 h) decreased, while pretreatment with 1% Triton X-100 increased analytical ELISA sensitivity. The diagnostic specificity of ELISA was 100% (95% CI, 91.19–100.00%) and sensitivity was 52.94% (95% CI, 35.13–70.22%) compared to rtRT-PCR (Ct < 40). Profoundly higher sensitivity was obtained using patient samples mostly containing Wuhan-similar variants (Wuhan, alpha, and delta), 62.50% (95% CI, 40.59 to 81.20%), in comparison to samples mostly containing Wuhan-distant variants (Omicron) 30.00% (6.67–65.25%). The developed product has relatively high diagnostic sensitivity in relation to its analytical sensitivity due to the usage of polyclonal antibodies from two species, providing a wide repertoire of antibodies against multiple N protein epitopes. Moreover, the fast, simple, and inexpensive production of polyclonal antibodies, as the most expensive assay components, would result in affordable antigen tests