Bioavailability of Orally Administered Active Lipid Compounds from four Different Greenshell™ Mussel Formats

Bioactive fatty acids from non-conventional lipid sources and their potential application in functional food development

There is growing evidence that bioactive fatty acids (BFAs), including eicosapentaenoic acid (EPA; 20:5-3), docosahexaenoic acid (DHA; 22:6-3), and conjugated fatty acids offer multiple biological benefits and constitute ingredients in functional food development. Despite their potential, novel and alternative/nonconventional sources with unique bioactive properties to meet growing demand remain largely unexplored, poorly characterized, and their effects are not well understood. We systematically reviewed the literature to identify studies on alternative sources of BFAs, their functions, extraction, and application in the food and nutraceutical industry. Twenty studies delved into alternate sources such as plants, bacteria, and algae. Six studies found EPA and DHA as the dominant FA in algal sources, while ten studies reported several BFAs from plant sources. Five studies assessed the health benefits of docosapentaenoic acid (DPA), arachidonic acid (ARA), EPA, γ-linolenic acid (GLA), and linoleic acid (LA). Eleven studies compared the quality of oil recovered by green solvents, pressurized liquid, supercritical fluid, and assisted extraction methods. Three studies assessed the effects of assisted extraction methods and reported that these approaches improved oil yield and quality, but the findings may have limited applicability to other lipid sources. The quality of nonconventional lipids largely depends on extraction techniques. Four studies suggested methods like 1D and 2D NMR spectroscopy, LC-MS/MS; however, their analytical differences make accurate comparison inadequate. Five studies found that the incorporation of algal and seafood biolipids during product development increased EHA and DHA contents.

Effects of Greenshell™ mussel intervention on biomarkers of cartilage metabolism, inflammatory markers and joint symptoms in overweight/obese postmenopausal women: A randomized, double-blind, and placebo-controlled trial

Objective

To investigate the effect of whole greenshell mussel (GSM) powder on biomarkers of cartilage metabolism, inflammatory cytokines, and joint symptoms in postmenopausal women with overweight/obesity and joint discomfort.

Design

Fifty-five postmenopausal women with overweight/obesity were randomly assigned to receive 3 g/day whole GSM powder or placebo for 12 weeks. Cartilage turnover biomarkers urinary C-telopeptide of type II collagen (CTX-II) and serum cartilage oligomeric matrix protein (COMP) were measured at baseline, week 6 and 12. Plasma cytokines were measured at baseline and week 12. Joint pain and knee-related problems were assessed at baseline and week 12 using a 100 mm Visual Analogue Scale (VAS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, respectively.

Results

Forty-nine participants completed the study (GSM n = 25, placebo n = 24). After 12 weeks, urinary CTX-II showed no significant change over time or between the groups (interaction effect P = 0.1). However, in women with symptomatic knees, a significant difference was noted between the group (treatment effect P = 0.04), as it was lower in the GSM group compared to placebo group at week 6 (P = 0.04) and week 12 (P = 0.03). Serum COMP and plasma cytokines were not affected. GSM supplementation showed greater reduction in the VAS pain score than placebo (-13.2 ± 20.3 vs. -2.9 ± 15.9; P = 0.04). No significant change in KOOS domains between the two groups was observed.

Conclusion

Oral supplementation of whole GSM powder at 3 g/day may slow down the degradation of type II collagen in postmenopausal women with symptomatic knees. GSM treatment conferred clinical benefit on overall joint pain. No significant effect was noted for inflammatory cytokines, suggesting that GSM may act within the joint microenvironment rather than at the systemic level.

Clinical trial registration

[www.australianclinicaltrials.gov.au/clinical-trialregistries], identifier [ACTRN12620000413921p].

Cryopreservation of six Symbiodiniaceae genera and assessment of fatty acid profiles in response to increased salinity treatments

Symbiodiniaceae are a diverse group of dinoflagellates, the majority of which are free-living and/or associated with a variety of protists and other invertebrate hosts. Maintenance of isolated cultures is labour-intensive and expensive, and cryopreservation provides an excellent avenue for their long-term storage. We aimed to cryopreserve 15 cultured isolates from six Symbiodiniaceae genera using dimethyl sulfoxide (DMSO) as the cryoprotectant agent (CPA). Under 15% DMSO, 10 isolates were successfully cryopreserved using either rapid freezing or controlled-rate freezing. Cultures that failed or had low survival, were subjected to (1) a reduction of CPA to 10%, or (2) increased salinity treatment before freezing. At 10% DMSO, three further isolates were successfully cryopreserved. At 15% DMSO there were high cell viabilities in Symbiodinium pilosum treated with 44 parts per thousand (ppt) and 54 ppt culture medium. An isolate of Fugacium sp. successfully cryopreserved after salinity treatments of 54 ppt and 64 ppt. Fatty acid (FA) analyses of S. pilosum after 54 ppt salinity treatment showed increased saturated FA levels, whereas Fugacium sp. had low poly-unsaturated FAs compared to normal salinity (34 ppt). Understanding the effects of salinity and roles of FAs in cryopreservation will help in developing protocols for these ecologically important taxa.

Non-polar lipid from greenshell mussel (Perna canaliculus) inhibits osteoclast differentiation

The osteoclast-dependent bone resorption process is a crucial part of the bone regulatory system. The excessive function of osteoclasts can cause diseases of bone, joint, and other tissues such as osteoporosis and osteoarthritis. Greenshell mussel oil (GSM), a good source of long chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs), was fractionated into total lipid, polar lipid, and non-polar lipid components and their anti-osteoclastogenic activity tested in RAW 264.7 cell cultures. Osteoclast differentiation process was achieved after 5 days of incubation with RANKL in 24-well culture plates. Introducing the non-polar lipid fraction into the culture caused a lack of cell differentiation, and a reduction in tartrate-resistant acid phosphatase (TRAP) activity and TRAP cell numbers in a dose-dependent manner (50% reduction at the concentration of 20 μg/mL, p < 0.001). Moreover, actin ring formation was significantly diminished by non-polar lipids at 10-20 μg/mL. The bone digestive enzymes released by osteoclasts into the pit formation were also compromised by downregulating gene expression of cathepsin K, carbonic anhydrase II (CA II), matrix metalloproteinase 9 (MMP-9), and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1). This study revealed that the non-polar lipid fraction of GSM oil contains bioactive substances which possess potent anti-osteoclastogenic activity.