Starfish (Asterias rubens) as a New Source of Marine Lipids: Effect of Season, Size and Oil Extraction Methods.

The increasing demand for oils that contain health-beneficial omega-3 fatty acids calls for new resources or better utilization of existing resources, such as side-streams or underutilized resources to maintain a sustainable fishery. Starfish has been, until recently, an unexploited resource with limited utilization. Currently, starfish is processed into starfish meal for feed. However, the content of bioactive compounds, such as omega-3 fatty acids and phospholipids, could make it a new source of marine oil containing omega-3 fatty acids for human consumption. The aim of this study was to map the composition of bioactive compounds in starfish and starfish meal at different harvesting times to elucidate the content and variation over seasons. The results showed that starfish is a good source of marine omega-3 fatty acids and rich in phospholipids. Some variation was observed in the composition, especially for EPA bound to phospholipids, which was significantly higher in the spring. Traditional extraction using heat and mechanical separation was not applicable to the starfish, and neither was enzyme-assisted extraction. On the other hand, the supercritical CO2 extraction method using EtOH as a co-solvent seemed to be a promising green technology for extracting not only non-polar lipids, but also polar lipids, such as phospholipids. However, the conditions for extraction need further optimization.

Anticancer and Apoptotic Activity in Cervical Adenocarcinoma HeLa Using Crude Extract of Ganoderma applanatum.

Cancer is currently one of the foremost health challenges and a leading cause of death worldwide. Cervical cancer is caused by cofactors, including oral contraceptive use, smoking, multiparity, and HIV infection. One of the major and considerable etiologies is the persistent infection of the oncogenic human papilloma virus. G. applanatum is a valuable medicinal mushroom that has been widely used as a folk medicine for the treatment and prevention of various diseases. In this study, we obtained crude extract from G. applanatum mushroom with a subcritical water extraction method; cell viability assay was carried out and the crude extract showed an antiproliferative effect in HeLa cells with IC50 of 1.55 ± 0.01 mg/mL; however, it did not show any sign of toxicity in HaCaT. Protein expression was detected by Western blot, stability of IκBα and downregulation of NFκB, IKKα, IKKß, p-NFκB-65(Ser 536) and p-IKKα/ß(Ser 176/180), suggesting loss of survival in a dose-dependent manner. RT-qPCR revealed RNA/mRNA expression; fold changes of gene expression in Apaf-1, caspase-3, cytochrome-c, caspase-9, Bax and Bak were increased, which implies apoptosis, and NFκB was decreased in a dose-dependent manner. DNA fragmentation was seen in the treatment groups as compared to the control group using gel electrophoresis. Identification and quantification of compounds were carried out by GC-MS and HPLC, respectively; 2(5H)furanone with IC50 of 1.99 ± 0.01 µg/mL could be the responsible anticancer compound. In conclusion, these findings suggest the potential use of the crude extract of G. applanatum as a natural source with anticancer activity against cervical cancer.

Effect of Extraction Temperature on Pressurized Liquid Extraction of Bioactive Compounds from Fucus vesiculosus.

This study was aimed at investigating the effect of low polarity water (LPW) on the extraction of bioactive compounds from Fucus vesiculosus and to examine the influence of temperature on the extraction yield, total phenolic content, crude alginate, fucoidan content, and antioxidant activity. The extractions were performed at the temperature range of 120-200 °C with 10 °C increments, and the extraction yield increased linearly with the increasing extraction temperature, with the highest yields at 170-200 °C and with the maximum extraction yield (25.99 ± 2.22%) at 190 °C. The total phenolic content also increased with increasing temperature. The extracts showed a high antioxidant activity, measured with DPPH (2,2-Diphenyl-1-picrylhydrazyl) radicals scavenging and metal-chelating activities of 0.14 mg/mL and 1.39 mg/mL, respectively. The highest yield of alginate and crude fucoidan were found at 140 °C and 160 °C, respectively. The alginate and crude fucoidan contents of the extract were 2.13% and 22.3%, respectively. This study showed that the extraction of bioactive compounds from seaweed could be selectively maximized by controlling the polarity of an environmentally friendly solvent.

Emerging Technologies for the Extraction of Marine Phenolics: Opportunities and Challenges.

Natural phenolic compounds are important classes of plant, microorganism, and algal secondary metabolites. They have well-documented beneficial biological activities. The marine environment is less explored than other environments but have huge potential for the discovery of new unique compounds with potential applications in, e.g., food, cosmetics, and pharmaceutical industries. To survive in a very harsh and challenging environment, marine organisms like several seaweed (macroalgae) species produce and accumulate several secondary metabolites, including marine phenolics in the cells. Traditionally, these compounds were extracted from their sample matrix using organic solvents. This conventional extraction method had several drawbacks such as a long extraction time, low extraction yield, co-extraction of other compounds, and usage of a huge volume of one or more organic solvents, which consequently results in environmental pollution. To mitigate these drawbacks, newly emerging technologies, such as enzyme-assisted extraction (EAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE) have received huge interest from researchers around the world. Therefore, in this review, the most recent and emerging technologies are discussed for the extraction of marine phenolic compounds of interest for their antioxidant and other bioactivity in, e.g., cosmetic and food industry. Moreover, the opportunities and the bottleneck for upscaling of these technologies are also presented.

Green extraction of polyphenolic-polysaccharide conjugates from Pseuderanthemum palatiferum (Nees) Radlk.: Chemical profile and anticoagulant activity.

In this study, pressurized liquid extraction (PLE) of polyphenolic-polysaccharide (PP) from Pseuderanthemum palatiferum (Nees) Radlk. leaves was carried out and compared with a conventional technique using 0.1 M sodium hydroxide. The extracts were purified according to the method reported previously to obtain PP conjugates which were further studied about chemical profiles and anticoagulant activity. Fourier-transform infrared spectroscopy (FTIR), UV-Vis, nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and spectrophotometry analysis were used to characterize the selected PP conjugates. The results showed that PP conjugates comprised of carbohydrate, phenolic, and protein constituents with the yield ranged from 2.76% to 14.34%. Seven mono sugars containing in all conjugates were determined using high-performance liquid chromatography (HPLC), namely, arabinose, fucose, galactose, glucose, mannose, rhamnose, and xylose. PP conjugates obtained from PLE at 150 °C (PP-PLE5) exhibited better anticoagulant activity than those found at 200 °C and comparable to that of the conventional technique. On gel permeation chromatography, PP-PLE5 showed a broad molecular mass from 6 to 642 kDa. From the obtained results, PLE can be used as a green effective technique for the recovery of PP conjugate from P. palatiferum leaves.

Characterization of pepsin-solubilised collagen recovered from mackerel (Scomber japonicus) bone and skin using subcritical water hydrolysis.

This study was aimed at isolation of pepsin-solubilised collagen (PSC) from Mackerel (Scomber japonicus) bone and skin in order to effectively valorise these abundant wastes. The yield of PSC (8.10%) from skin was considerably higher than that from bone (1.75%). Based on the protein patterns, both PSCs were type Ι, and consisted of two α-chains. Fourier-transform infrared spectra demonstrated that PSCs from the bone and skin exhibited a triple-helical structure. The denaturation temperatures (Td) of the PSCs from bone and skin were 27 and 30 °C, respectively. Low-molecular-weight peptides (<1650 Da) were generated from both PSCs after subcritical water hydrolysis treatment. Glycine accounted for 30% of the total amino acids identified in both PSC hydrolysates. The antioxidant activities of both PSC hydrolysates were significantly higher than those of the isolated PSCs. Therefore, PSC hydrolysates can be used as a functional ingredient in the food, cosmetic and pharmaceutical industries.

Optimization of polysaccharides extraction from Pacific oyster (Crassostrea gigas) using subcritical water: Structural characterization and biological activities.

Bioactive polysaccharide was extracted from Pacific oyster Crassostrea gigas using subcritical water (SW) and the extraction process was optimize by response surface methodology (RSM). The optimum condition was found to be temperature 125.01 °C, extraction time 14.93 min, and liquid to solid ratio of 44.69:1 (ml:g). At this condition, the yield of the C. gigas polysaccharides (CGPs) was found to be 18.66%. The polysaccharide was characterized for its chemical, physical, thermal, and structural properties using HPLC, GPC, XRD, FTIR, TGA, UV-Vis spectroscopy, and NMR and the results of this characterization showed a characteristic feature of a typical polysaccharide. The CGPs was found to be a d-glucan with α-(1 → 4) configuration. The CGPs was also evaluated for its antioxidant, antihypertensive, and hypoglycemic activity and the IC50 (mg/ml) values were found to be 2.06 ±â€¯0.33, 1.58 ±â€¯0.03, and 2.77 ±â€¯0.01 respectively. The current study demonstrated that SWE could be used as an effective process to extract bioactive polysaccharides from C. gigas.

Effect of pretreatments on isolation of bioactive polysaccharides from spent coffee grounds using subcritical water.

In this study, we used a novel approach to recover polysaccharide from spent coffee ground (SCG) by combining pretreatments and subcritical water hydrolysis (SCWH). The independent variables which affect SCWH were optimized using response surface methodology. The highest yield of SCG polysaccharides (SCGPSs) (18.25 ±â€¯0.21%) was obtained using ultrasonic pretreatment and SCWH conditions of temperature (178.85 °C), pressure (20 bar), and extraction time (5 min). The extracted SCGPSs showed high antioxidant activity as measured using ABTS+ and DPPH radical scavenging assay with IC50 values of 1.83 ±â€¯0.03 and 2.66 ±â€¯0.13 mg/ml respectively. SCGPSs also showed in vitro hypoglycemic activities. The structural and thermal characterization of the polysaccharide showed that the extracted polysaccharide has a typical carbohydrate features. The results of this study suggested that the extracted polysaccharide could have a potential application in food and related industries.

Molecular modification of native coffee polysaccharide using subcritical water treatment: Structural characterization, antioxidant, and DNA protecting activities.

Polysaccharides are an abundant resource in coffee beans and have proved to show numerous bioactivities. Despite their abundance, their activities are not always satisfactory mostly due to their structure and large molecular size. Molecular modifications of native polysaccharides can overcome this problem. In this study, we used a novel and green method to modify native coffee polysaccharides using subcritical water (SCW) treatment. The SCW treatment was used at the temperature of 180°C-220°C and pressure of 30-60bar. The molecular and structural modification of the polysaccharides was confirmed using several techniques such as FT-IR, UV spectroscopy, XRD, and TGA. The antioxidant activity of the modified polysaccharides was evaluated using several chemical and Saccharomyces cerevisiae-based high throughput assays. The modified polysaccharides showed high antioxidant activities in all tested assays. Moreover, the polysaccharides showed high DNA protection activities. Therefore, SCW could be employed as a green solvent for molecular modification of polysaccharides.