Comparison of n-3 polyunsaturated fatty acid contents of wild and cultured Australian abalone

Detrimental influence of industrial effluents, especially heavy metals, on limnological parameters of water and nutritional profile in addition to enzymatic activities of fish, Sperata seenghala (Sykes, 1839) from diverse Ramsar sites, India (Punjab)

The present research was designed to determine the nutritive value of the liver and intestine of fish, Sperata seenghala, the impact of effluence load on limnological parameters of water and proximate composition of fish organs, especially on fatty acids, liver enzymatic activities, seasonal variations in the nutritional profile of fish, and to check and compare the pollution status of Ramsar sites in Punjab by calculating the water quality index, heavy metal pollution index, and metal index from June 2018 to August 2020. WQI of Harike wetland was found to be 53.95, which depicts that water quality in this region is "poor". At Nangal wetland, water quality index was reported to be "excellent" quality water and fit for the whole ecological unit. Overall heavy metal pollution index for Harike wetland was reported 174.569, whereas for Nangal wetland it was 5.994, depicting massive contaminant loads in a polluted region. MI value was also recorded as being higher (6.9336) in polluted habitat than in control habitat (0.8175). In fish liver, significant (p < 0.05) higher mean total lipids (6.73%), total proteins (3.98%), moisture (77.69%), ash (3.56%), and carbohydrates (3.79%) were observed in the samples from Nangal wetland than Harike wetland. A similar trend was reported in all biochemical contents of the fish intestine. Enzyme activities such as aspartate-aminotransferase and alanine-aminotransferase were significantly elevated (p < 0.05) in the specimens collected from the polluted region. The mean total n-3 (except in spring), n-6 polyunsaturated fatty acids (except in winter), and average monounsaturated and saturated fatty acids diminished significantly (p < 0.05) in the liver of fish from contaminated habitat than control site. In the intestine of fish collected from the polluted region, significant reductions in the mean total n-3 (except in autumn as well as summer), total n-6 PUFAs (in autumn and winter), and total SFAs were reported than control site.

Effect of seasonal temperature shifts on body homeostasis, biochemical parameters and chemical composition of green ormer (Haliotis tuberculata) in the Northern Adriatic

Seasonal responses of green ormer in terms of antioxidant capacity and lipid peroxidation, proximate and fatty acid tissue composition, trace and macro elements concentrations over the seasons were studied in relation to temperature shifts in the Northern Adriatic Sea. Overall antioxidative defenses (SOD, TBARS, TAS, LDH) varied significantly (p < 0.001) according to seasons (primarily spring and summer). The proportions of overall SFA were highest in summer. The proportions of MUFA increased in autumn, with significant differences between genders in spring and summer, and spring, summer and autumn for C18:1n7 and C20:4n6. The only fatty acid lacking significant variation between seasons was C22:5n3. Significant overall differences were observed in summer vs. winter samples for As, Ba, Co, Ni, Mn, Pb, Sb, and Se content in soft tissues, however, gender variations were not significant. The data obtained in the study are of utmost importance for the management of this under-investigated species.

Fatty Acid Profile in Fat Obtained from Edible Part of Land Snails Harvested in Poland

Introduction

The objective was to determine the content of fatty acids in edible snail fat by snail species, collection site, and processing stage.

Material and Methods

The research material comprised 180 edible fat samples from the three genera of edible snails collected in Poland: free-living Helix pomatia (HP) and two cultivated Cornu subspecies: C. aspersa maxima (CAM) and C. aspersum aspersum (CAA). All snails came from the Greater Poland and Lower Silesian Provinces: HP from their natural habitat and CAM and CAA from heliciculture farms. The studies focused on the raw meat, cooked meat, and frozen meat processing stages. Fatty acid (FA) profiles were determined by the gas chromatography method.

Results

Helix pomatia fat showed a higher saturated fatty acid (SFA) content, whereas the fat of Cornu genus snails had a higher unsaturated fatty acid (UFA) component, i.e. monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA). Thermal processing of snail meat increased all the determined SFA and decreased all the PUFA values, and increased the content of C18:1, C20:1, and C22:1 acids in the MUFA group. The material collection site had limited impact on FA content as differences were noted only in levels of C18:1, C18:2 n6, and C20:5. The differences pertained only to the fat of farmed snails of the Cornu genus.

Conclusion

Due to the high content of UFA and a favourable ratio of n6:n3 acids and PUFA:SFA, snail fat can be regarded as nutritionally valuable.

Fish oil supplementation and insulin sensitivity: a systematic review and meta-analysis

Background

Fish oil supplementation has been shown to be associated with a lower risk of metabolic syndrome and benefit a wide range of chronic diseases, such as cardiovascular disease, type 2 diabetes and several types of cancers. However, the evidence of fish oil supplementation on glucose metabolism and insulin sensitivity is still controversial. This meta-analysis summarized the exist evidence of the relationship between fish oil supplementation and insulin sensitivity and aimed to evaluate whether fish oil supplementation could improve insulin sensitivity.

Methods

We searched the Cochrane Library, PubMed, Embase database for the relevant studies update to Dec 2016. Two researchers screened the literature independently by the selection and exclusion criteria. Studies were pooled using random effect models to estimate a pooled SMD and corresponding 95% CI. This meta-analysis was performed by Stata 13.1 software.

Results

A total of 17 studies with 672 participants were included in this meta-analysis study after screening from 498 published articles found after the initial search. In a pooled analysis, fish oil supplementation had no effects on insulin sensitivity compared with the placebo (SMD 0.17, 95%CI -0.15 to 0.48, p = 0.292). In subgroup analysis, fish oil supplementation could benefit insulin sensitivity among people who were experiencing at least one symptom of metabolic disorders (SMD 0.53, 95% CI 0.17 to 0.88, p < 0.001). Similarly, there were no significant differences between subgroups of methods of insulin sensitivity, doses of omega-3 polyunsaturated fatty acids (n-3 PUFA) of fish oil supplementation or duration of the intervention. The sensitivity analysis indicated that the results were robust.

Conclusions

Short-term fish oil supplementation is associated with increasing the insulin sensitivity among those people with metabolic disorders.

Therapeutic potential of abalone and status of bioactive molecules: A comprehensive review

Marine organisms are increasingly being investigated as sources of bioactive molecules with therapeutic applications as nutraceuticals and pharmaceuticals. In particular, nutraceuticals are gaining popularity worldwide owing to their therapeutic potential and incorporation in functional foods and dietary supplements. Abalone, a marine gastropod, contains a variety of bioactive compounds with anti-oxidant, anti-thrombotic, anti-inflammatory, anti-microbial, and anti-cancer activities. For thousands of years different cultures have used abalone as a traditional functional food believing consumption provides health benefits. Abalone meat is one of the most precious commodities in Asian markets where it is considered a culinary delicacy. Recent research has revealed that abalone is composed of many vital moieties like polysaccharides, proteins, and fatty acids that provide health benefits beyond basic nutrition. A review of past and present research is presented with relevance to the therapeutic potential of bioactive molecules from abalone.

Differences in muscle cellularity and flesh quality between wild and farmed Coilia nasus (Engraulidae)

BACKGROUND

Populations of Coilia nasus, an anadromous fish, have declined dramatically in the Yangtze River estuary and its associated lakes owing to excessive fishing and changes in aquatic ecology. Recently, the success of artificial breeding programmes and advanced methods of propagation have allowed great increases in production of this species. Thus, to gain a better understanding of the flesh quality of C. nasus, muscle cellularity and quality parameters of the flesh were studied in wild and farmed specimens.

RESULTS

Muscle cellularity was different between wild and farmed fish. Muscle fibre density was significantly higher in farmed specimens, while muscle fibre diameter was higher in wild specimens. Farmed fish had higher moisture, hydroxyproline and collagen contents and a lower fat content compared with wild fish. No significant differences in textural parameters were found between the two groups. Saturated (SFA), polyunsaturated (PUFA) and total n-6 fatty acid contents were significantly higher in farmed fish, but monounsaturated fatty acid (MUPA) content was higher in wild fish.

CONCLUSION

The variation in the studied parameters determined significant differences in the flesh quality of wild and farmed C. nasus. Depending on muscle cellularity and fatty acid composition, farmed fish could be more suitable for human consumption than wild fish.

Dietary fish oil supplements increase tissue n-3 fatty acid composition and expression of delta-6 desaturase and elongase-2 in Jade Tiger hybrid abalone

This study was conducted to investigate the effects of fish oil (FO) supplements on fatty acid composition and the expression of ∆6 desaturase and elongase 2 genes in Jade Tiger abalone. Five test diets were formulated to contain 0.5, 1.0, 1.5, 2.0 and 2.5% of FO respectively, and the control diet was the normal commercial abalone diet with no additional FO supplement. The muscle, gonad and digestive glands (DG) of abalone fed with all of the five test diets showed significantly high levels of total n-3 polyunsaturated fatty acid (PUFA), eicosapentaenoic acid (EPA), docosapentaenoic acid n-3 (DPAn-3), and docosahexaenoic acid (DHA) than the control group. In all three types of tissue, abalone fed diet supplemented with 1.5% FO showed the highest level of these fatty acids (P < 0.05). For DPAn-3 the higher level was also found in muscle and gonad of abalone fed diet supplemented with 2% FO (P < 0.05). Elongase 2 expression was markedly higher in the muscle of abalone fed diet supplemented with 1.5% FO (P < 0.05), followed by the diet containing 2% FO supplement. For ∆6 desaturase, significantly higher expression was observed in muscle of abalone fed with diet containing 0.5% FO supplement (P < 0.05). Supplementation with FO in the normal commercial diet can significantly improve long chain n-3 PUFA level in cultured abalone, with 1.5% being the most effective supplementation level.

Effects of simulated digests of Biota orientalis and a dietary nutraceutical on interleukin-1- induced inflammatory responses in cartilage explants

OBJECTIVE

To test the hypothesis that simulated digests of Biota orientalis (BO) and a dietary nutraceutical (DN; composed of mussel, shark cartilage, abalone, and BO seed lipid extract) inhibit prostaglandin E2 (PGE2), nitric oxide (NO), and glycosaminoglycan (GAG) production in interleukin (IL)-1-stimulated cartilage explants.

SAMPLE POPULATION

Cartilage tissue from 12 pigs.

PROCEDURES

Articular cartilage explants were conditioned with a simulated digest of BO (BOsim) or DN (DNsim) at concentrations of 0, 0.06, or 0.18 mg/mL or indomethacin (INDOsim; 0 or 0.02 mg/mL) for 72 hours. Control explants received digest vehicle only. Explants were or were not stimulated with recombinant human-IL-1beta (10 or 0 ng/mL) during the final 48 hours of culture. Concentrations of PGE2, GAG, and NO in media samples (mPGE2,mGAG, and mNO concentrations, respectively) were analyzed, and explant tissue was stained fluorochromatically to determine chondrocyte viability. Treatment effects during the final 48-hour culture period were analyzed.

RESULTS

IL-1 increased mPGE2, mGAG, and mNO concentrations in control explants without adversely affecting cell viability. Treatment with INDOsim blocked PGE2 production and increased mNO concentration in IL-1-stimulated and unstimulated explants and increased mGAG concentration in unstimulated explants. Treatment with DNsim (0.06 and 0.18 mg/mL) reduced mPGE2 concentration in IL-1-stimulated and unstimulated explants, reduced mNO concentration in IL-1-stimulated explants, and increased mNO concentration in unstimulated explants. Treatment with 0.18 mg of DNsim/mL increased cell viability in the presence of IL-1. In IL-1-stimulated explants, BOsim (0.06 and 0.18 mg/mL) reduced mPGE2 concentration, but 0.18 mg of BOsim/mL increased cell viability.

CONCLUSIONS AND CLINICAL RELEVANCE

Effects of IL-1 on cartilage explants in vitro were modulated by DNsim and BOsim.

Isolation and characterization of unsaturated fatty acids during bacteriorhodopsin preparation from Halobacterium halobium

AIMS

Isolation and characterization of unsaturated fatty acids during bacteriorhodopsin preparation from Halobacterium halobium.

METHODS AND RESULTS

Halobacterium halobium was cultivated in a composite medium. Cells were collected by centrifugation followed by ultrasonic disruption, and the resulting suspension was subject to centrifugation for preparation of both pellet and supernatant. The pellet was saved in order to prepare bacteriorhodopsin, while the supernatant was used for the isolation of crude fatty acids by saponification and extraction. Crystallization then took place in acetone at -16 degrees C to remove fatty acids in which the carbon chain length was shorter than 13. The sample was obtained after purification and analysed by gas chromatography. The results demonstrated that Halobacterium halobium could synthesize multiple unsaturated fatty acids, particularly the three important polyunsaturated fatty acids arachidonic acid (1.12%), eicosapentaenoic acid (16.76%) and docosahexaenoic acid (9.38%).

CONCLUSION

Important unsaturated fatty acids were isolated and characterized from the waste, which was produced during the preparation of bacteriorhodopsin from Halobacterium halobium.

SIGNIFICANCE AND IMPACT OF THE STUDY

Halobacterium halobium has already been used for decades to prepare bacteriorhodopsin. We found that several important unsaturated fatty acids could be extracted from the bacterial waste, which extends its application scope and might bring additional benefits to humanity.

Anti-inflammatory and chondroprotective effects of nutraceuticals from Sasha's Blend in a cartilage explant model of inflammation

New Zealand green lipped mussel (NZGLM), abalone (AB), and shark cartilage (SC) are extensively used for treatment of and/or as preventatives for arthritis, despite a relative paucity of scientific evidence for efficacy. This research integrated a simulated digestion protocol with ultrafiltration and cartilage explants to generate new information on the anti-inflammatory and chondroprotective properties of NZGLM, SC, and AB. Each nutraceutical was artificially digested using simulated gastric and intestinal fluids, and the crude digest was ultrafiltered (50 kDa). Each filtrate was applied individually to cartilage explants before the explants were stimulated with IL-1 to induce an acute inflammatory response. Media were collected daily for 48 h and analyzed for prostaglandin E(2) (PGE(2)), glycosaminoglycan (GAG), and nitric oxide (NO), and cartilage tissue was differentially stained to determine the relative proportion of live and dead cells. SC and NZGLM significantly inhibited IL-1-induced PGE(2) synthesis and IL-1-induced GAG release, and AB was an effective inhibitor of IL-1-induced NO production. The three test nutraceuticals affect at least three major pathways involved in the catabolic cycle of arthritis and may prove important treatments and/or preventatives for the pain and degradation associated with this condition. The methodology and results describe a useful model for evaluating dietary nutraceuticals in vitro.

Seasonal Variations of Lipid Content and Composition in Perna viridis

The total lipid content, composition of main lipid classes, composition of sterols and composition of fatty acids in the main glycerolipids of Perna viridis were analyzed through four seasons using TLC-FID and GLC. Mussel samples were collected during different seasons between 2003 and 2004 from Shengsi Island, Zhejiang Province, China and stored frozen prior to freeze-drying and lipid extraction. Ten grams of dried mussel powder of each season were analyzed. Total lipid content ranged from 14.5 g/100 g in spring month to 7.8 g/100 g dried mussel powder in autumn month. The predominant lipid in spring month was triacylglycerol (TAG), however, in the other three seasons the phospholipids (PL) was the main lipid class. The most abundant fatty acid in TAG, PL and phosphatidylcholine (PC) was 16:0, with the summer samples having the highest proportion (24-30% of total fatty acid) and winter the lowest (14-22%). In phosphatidylethanolamine (PE), the spring samples had the highest proportions of 16:0. The predominant polyunsaturated fatty acids (PUFA) were 22:6n-3 and 20:5n-3 in TAG, PL, PE and PC (25-40%). The proportions of 22:6n-3 and 20:5n-3 were higher in spring than in other seasons in PL and PE. There were nine sterols identified, with cholesterol being the predominant sterol, and other main ones were desmostersol/brassicasterol and 24-methylenecholesterol. Proportions of other fatty acids in different lipid fractions and the sterol compositions as well also varied seasonally. There were subject to the seasonal variations. Differences in lipid content and composition, fatty acid composition in different lipid fractions may be caused by multiple factors such as lifecycle, sex, variation of plankton in different seasons and temperature, which could influence physiological activities and metabolism.