Bioaccessibility of Phenolic Compounds, Resistant Starch, and Dietary Fibers from Australian Green Banana during In Vitro Digestion and Colonic Fermentation.

Green bananas contain a substantial amount of resistant starch (RS), dietary fiber (DF), and phytochemicals, which exhibit potent antioxidant capabilities, primarily attributable to the abundance of polyphenols. The objective of this study was to assess the variations in the contents and bioaccessibility of RS, DF, and phenolic compounds in three types of Australian green bananas (Cavendish "Musa acuminata", Ladyfinger "Musa paradisiaca L.", and Ducasse "Musa balbisiana"), along with their antioxidant capacities, and the production of short-chain fatty acids (SCFAs) following in vitro simulated gastrointestinal digestion and colonic fermentation. The studied cultivars exhibited significant levels of RS, with Ladyfinger showing the greatest (49%). However, Ducasse bananas had the greatest DF concentration (38.73%). Greater TPC levels for Ladyfinger (2.32 mg GAE/g), as well as TFC and TTC (0.06 mg QE/g and 3.2 mg CE/g, respectively) in Cavendish, together with strong antioxidant capacities (DPPH, 0.89 mg TE/g in Cavendish), have been detected after both intestinal phase and colonic fermentation at 12 and 24 h. The bioaccessibility of most phenolic compounds from bananas was high after gastric and small intestinal digestion. Nevertheless, a significant proportion of kaempferol (31% in Cavendish) remained detectable in the residue after colonic fermentation. The greatest production of SCFAs in all banana cultivars was observed after 24 h of fermentation, except valeric acid, which exhibited the greatest output after 12 h of fermentation. In conclusion, the consumption of whole green bananas may have an advantageous effect on bowel health and offer antioxidant characteristics.

Unraveling the bioactive interplay: seaweed polysaccharide, polyphenol and their gut modulation effect.

Seaweed is rich in many unique bioactive compounds such as polyphenols and sulfated polysaccharides that are not found in terrestrial plant. The discovery of numerous biological activities from seaweed has made seaweed an attractive functional food source with the potential to be exploited for human health benefits. During food processing and digestion, cell wall polysaccharide and polyphenols commonly interact, and this may influence the nutritional properties of food. Interactions between cell wall polysaccharide and polyphenols in plant-based system has been extensively studied. However, similar interactions in seaweed have received little attention despite the vast disparity between the structural and chemical composition of plant and seaweed cell wall. This poses a challenge in extracting seaweed bioactive compounds with intact biological properties. This review aims to summarize the cell wall polysaccharide and polyphenols present in brown, red and green seaweed, and current knowledge on their potential interactions. Moreover, this review gives an overview of the gut modulation effect of seaweed polysaccharide and polyphenol.

Extraction and Characterization of Bioactive Compounds from Diverse Marine Microalgae and Their Potential Antioxidant Activities.

This study compared free and bound phenolic compounds in various marine microalgae species. It assessed total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TCT) and their antioxidant capacities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) radical cation-based assay and ferric ion reducing antioxidant power assay. Liquid chromatography-mass spectrometry (LC-MS) was also employed to characterize the phenolic profiling. Results showed that free phenolic compounds ranged from 1.83-6.45 mg GAE/g d. w., while bound phenolic compounds ranged from 4.03-26.03 mg GAE/g d. w., indicating significant differences. These variations were consistent across assays, highlining unique profiles in different species. A total 10 phenolics were found in these seven microalgae, including 1 phenolic acid, 6 flavonoids, 1 other polyphenol and 2 lignans. 4'-O-methyl-(-)-epigallocatechin 7-O-glucuronide and chrysoeriol 7-O-glucoside in microalgae were firstly reported in microalgal samples. These findings have implications for future applications in industries.

Fibre fermentation and pig faecal microbiota composition are affected by the interaction between sugarcane fibre and (poly)phenols in vitro.

We investigated the effects of (poly)phenol-rich sugarcane extract (PRSE), sugarcane fibre (SCFiber), and the combination of them (PRSE + SCFiber) on the gut microbiota and short-chain fatty acids (SCFA) production using in vitro digestion and pig faecal fermentation. Measuring total phenolic content and antioxidant activity through the in vitro digestion stages showed that PRSE + SCFiber increased the delivery of (poly)phenols to the in vitro colonic fermentation stage compared to PRSE alone. The PRSE + SCFiber modulated the faecal microbiota profile by enhancing the relative abundances of Prevotella, Lactobacillus, and Blautia, and reducing the relative abundance of Streptococcus. PRSE + SCFiber also mitigated the inhibitory effects of PRSE on SCFA production. These results suggest that the inclusion of sugarcane fibre with PRSE could increase the availability of phenolic compounds in the colon and modulate the gut microbiota towards a more favourable profile.

Sesquiterpenoid lactones as potential anti-cancer agents: an update on molecular mechanisms and recent studies.

Plants-based natural compounds are well-identified and recognized chemoprotective agents that can be used for primary and secondary cancer prevention, as they have proven efficacy and fewer side effects. In today's scenario, when cancer cases rapidly increase in developed and developing countries, the anti-cancerous plant-based compounds become highly imperative. Among others, the Asteraceae (Compositae) family's plants are rich in sesquiterpenoid lactones, a subclass of terpenoids with wide structural diversity, and offer unique anti-cancerous effects. These plants are utilized in folk medicine against numerous diseases worldwide. However, these plants are now a part of the modern medical system, with their sesquiterpenoid lactones researched extensively to find more effective and efficient cancer drug regimens. Given the evolving importance of sesquiterpenoid lactones for cancer research, this review comprehensively covers different domains in a spectrum of sesquiterpenoid lactones viz (i) Guaianolides (ii) Pseudoguaianolide (iii) Eudesmanolide (iv) Melampodinin A and (v) Germacrene, from important plants such as Cynara scolymus (globe artichoke), Arnica montana (wolf weeds), Spilanthes acmella, Taraxacum officinale, Melampodium, Solidago spp. The review, therefore, envisages being a helpful resource for the growth of plant-based anti-cancerous drug development.

Seaweed Phenolics as Natural Antioxidants, Aquafeed Additives, Veterinary Treatments and Cross-Linkers for Microencapsulation.

Driven by consumer demand and government policies, synthetic additives in aquafeed require substitution with sustainable and natural alternatives. Seaweeds have been shown to be a sustainable marine source of novel bioactive phenolic compounds that can be used in food, animal and aqua feeds, or microencapsulation applications. For example, phlorotannins are a structurally unique polymeric phenolic group exclusively found in brown seaweed that act through multiple antioxidant mechanisms. Seaweed phenolics show high affinities for binding proteins via covalent and non-covalent bonds and can have specific bioactivities due to their structures and associated physicochemical properties. Their ability to act as protein cross-linkers means they can be used to enhance the rheological and mechanical properties of food-grade delivery systems, such as microencapsulation, which is a new area of investigation illustrating the versatility of seaweed phenolics. Here we review how seaweed phenolics can be used in a range of applications, with reference to their bioactivity and structural properties.

Targeting androgen receptor signaling with MicroRNAs and Curcumin: a promising therapeutic approach for Prostate Cancer Prevention and intervention.

Prostate cancer (PC) is a multifactorial disease characterized by the abrogation of androgen receptor signaling. Advancement in microbiology techniques has highlighted the significant role of microRNAs (miRNAs) in the progression of PC cells from an androgen-dependent to an androgen-independent state. At that stage, prostate tumors also fail to respond to currently practiced hormone therapies. So, studies in recent decades are focused on investigating the anti-tumor effects of natural compounds in PC. Curcumin is widely recognized and now of huge prestige for its anti-proliferative abilities in different types of cancer. However, its limited solubility, compatibility, and instability in the aqueous phase are major hurdles when administering. Nanoformulations have proven to be an excellent drug delivery system for various drugs and can be used as potential delivery platforms for curcumin in PC. In this review, a shed light is given on the miRNAs-mediated regulation of androgen receptor (AR) signaling and miRNA-curcumin interplay in PC, as well as on curcumin-based nanoformulations that can be used as possible therapeutic solutions for PC.

LC-ESI-QTOF-MS/MS characterization of phenolic compounds from Pyracantha coccinea M.Roem. and their antioxidant capacity.

Pyracantha coccinea M.Roem. is considered as an important medicinal plant contributing remarkably to health and medicinal benefits. This is attributed to the presence of abundant polyphenols with powerful antioxidant properties. However, little research has been studied on the comprehensive identification and characterization of the phenolic compounds in areal parts of P. coccinea.  This study aimed to investigate, characterize, and quantify the phenolic profiles of P. coccinea through liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS) and high-performance liquid chromatography-photodiode array (HPLC-PDA. Further, it showed a significantly higher value in total phenolic content (TPC) than that of total flavonoids (TFC) and tannins (TTC). As for antioxidant capacities, P. coccinea presented the highest activity in ABTS (7.12 ± 0.25 mg AAE/g dw) compared with DPPH, FRAP, and TAC assays. The LC-ESI-QTOF-MS/MS analysis detected 28 phenolic compounds, including phenolic acids (12), flavonoids (13), other polyphenols (2), and lignans (1) in P. coccinea samples. The results from HPLC-PDA indicated the chlorogenic acid (11.49 ± 1.89 mg/g) was the most abundant phenolic acid, while kaempferol (14.67 ± 2.17 mg/g) was the predominant flavonoid in P. coccinea. This research confirms the benefits of the P. coccinea plant as a potential source of natural antioxidants for the food and pharmaceutical industries.

LC-ESI-QTOF-MS/MS characterization of phenolic compounds from Prosopis farcta (Banks & Sol.) J.F.Macbr. and their potential antioxidant activities.

Prosopis farcta (Banks & Sol.) J.F.Macbr. is an emerging medicinal plant containing a diverse array of phytochemicals, including protein, fat, carbohydrate, fibre, alkaloids, fatty acids, glycosides, and polyphenols, with strong antioxidant potential. However, the screening and characterization of phenolic compounds in P. farcta is limited. This study is conducted to determine the polyphenol contents and their antioxidant activity in P. farcta leaves samples via liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS) and high-performance liquid chromatography-photodiode array (HPLC-PDA). Total phenolic content (TPC), total flavonoid content (TFC), and total tannins content (TTC) were determined for polyphenol estimation. The antioxidant properties were measured by total antioxidant capacity (TAC), 2,2'-Diphenyl-2-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and 2,2"²-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). LC-ESI-QTOF-MS/MS was used to identify and characterize 47 phenolic compounds, which mainly included phenolic acids (13), flavonoids (28), other polyphenols (4), lignans (1), and stilbenes (1). According to HPLC-PDA quantification, chlorogenic acid (9.78 ± 2.15 mg/g dw) was the most abundant phenolic acid, while the main flavonoids included catechin (12.73 ± 1.29 mg/g dw) and kaempferol (7.93 ± 1.47 mg/g dw). The study demonstrated the significance of P. farcta as a rich source of phenolic compounds with antioxidant capacity that can be widely used in food, beverage, feed, and pharmaceutical applications.

High-performance thin-layer chromatography fingerprinting, total phenolic and total flavonoid contents and anti-platelet-aggregation activities of Prosopis farcta extracts.

Cardiovascular diseases are a leading cause of worldwide death and excessive platelet is closely related with their pathogenesis. Different plants and natural compounds have demonstrated anti-platelet effects. The aim of this study was to report the high-performance thin-layer chromatography (HPTLC) fingerprinting and anti-platelet-aggregation activities of different leaf extracts (n-hexane, chloroform, ethyl acetate, methanol and aqueous) of Prosopis farcta (Syrian mesquite) plant. The results showed a 100% inhibition of aggregation activity after plasmatic adenosine diphosphate (ADP) aggregation activation of ethyl acetate, ethanolic, methanolic and aqueous extracts, at 60 mg/mL concentration. The IC50 ADP value of these extracts ranged between 4.07 and 11.39 mg/mL. Moreover, these extracts reported the highest amounts of phenolic and flavonoid contents. In conclusion, phytochemicals present in P. farcta leaves have anti-platelet-aggregation activities. Future studies are needed to identify the compounds with anti-platelet potential present in P. farcta.

LC-ESI-QTOF-MS/MS Characterization of Seaweed Phenolics and Their Antioxidant Potential.

Seaweed is an important food widely consumed in Asian countries. Seaweed has a diverse array of bioactive compounds, including dietary fiber, carbohydrate, protein, fatty acid, minerals and polyphenols, which contribute to the health benefits and commercial value of seaweed. Nevertheless, detailed information on polyphenol content in seaweeds is still limited. Therefore, the present work aimed to investigate the phenolic compounds present in eight seaweeds [Chlorophyta (green), Ulva sp., Caulerpa sp. and Codium sp.; Rhodophyta (red), Dasya sp., Grateloupia sp. and Centroceras sp.; Ochrophyta (brown), Ecklonia sp., Sargassum sp.], using liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The total phenolic content (TPC), total flavonoid content (TFC) and total tannin content (TTC) were determined. The antioxidant potential of seaweed was assessed using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, a 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical scavenging assay and a ferric reducing antioxidant power (FRAP) assay. Brown seaweed species showed the highest total polyphenol content, which correlated with the highest antioxidant potential. The LC-ESI-QTOF-MS/MS tentatively identified a total of 54 phenolic compounds present in the eight seaweeds. The largest number of phenolic compounds were present in Centroceras sp. followed by Ecklonia sp. and Caulerpa sp. Using high-performance liquid chromatography-photodiode array (HPLC-PDA) quantification, the most abundant phenolic compound was p-hydroxybenzoic acid, present in Ulva sp. at 846.083 ± 0.02 µg/g fresh weight. The results obtained indicate the importance of seaweed as a promising source of polyphenols with antioxidant properties, consistent with the health potential of seaweed in food, pharmaceutical and nutraceutical applications.

LC-ESI-QTOF/MS characterization of bioactive compounds from black spices and their potential antioxidant activities.

Black pepper (Piper nigrum L.), black cumin (Nigella sativa L.) and black cardamom (Amomum subulatum) are considered as important spices, seasoning and folk medicines. They have a diverse range of bioactive compounds, especially for polyphenolic compounds. These polyphenolic compounds contribute to the putative health benefits of these black spices. The purpose of this study was to identify, characterize and quantify the phenolic profile of these black spices using LC-ESI-QTOF/MS and HPLC-PDA and to access their antioxidant potential. The LC-ESI-QTOF/MS analysis led to the identification of 138 phenolic compounds in three black spices. In HPLC-PDA, the p-hydroxybenzoic acid was the most predominant phenolic acid in black pepper and black cumin while diosmin was the most abundant flavonoid in black cardamom (> 20 mg/g). Furthermore, black spices were systematically measured for their TPC, TFC and TTC followed by measurement of their antioxidant activities using DPPH, FRAP and ABTS assays. Black pepper showed the highest TPC, TFC, TTC, DPPH and ABTS activities as compared to other black spices while black cardamom exhibited the highest FRAP activity. The obtained results highlight the importance of these black spices as promising sources of phenolic compounds and they could be potentially utilized in food, feed and nutraceutical industries.

Oxidative stability and Sensoric acceptability of functional fish meat product supplemented with plant-based polyphenolic optimal extracts.

BACKGROUND: Fish meat and its products are usually accepted as good source of biological high value food components and especially for polyunsaturated fatty acids. The quality of fish meat products is considered to be decreased by the lipid peroxidation which leads to reduction in nutritional quality, financial loss and severe health problems. Many tactics are present to reserve their quality and safety. In the present investigation, the extraction and supplementation of optimal total polyphenol extracts (TPC) from vegetable and fruit by-products was explored for lipids oxidative stability and sensoric acceptability of functional fish product samples. METHODS: Vegetable and fruit by-products (cabbage leaves and banana peels) were collected from local fruits and vegetables processing industries. A 3-level five factor Box-Behnken design was used to study the effect of extraction/sonication temperature (°C), amplitude level, water/meal ratio, extraction/sonication time (minutes) and pH conditions for maximum yield of TPC from dried vegetable and fruit samples. The TPC samples were analyzed for chemical composition (total polyphenols, cyanogenic contents and tannins). Natural TPC extracts were supplemented at different concentration (0.5, 1 and 1.5%) to fish meat for preparation of different meat ball samples. The fish meat product samples without supplementation of TPC extract were kept as control. The partial/parfrying of the products was carried out to determine the lipid stability (peroxide value and free fatty acids) stored at refrigerator (for 9 days) and at - 18 °C in a freezer for a storage period of 60-days. The sensoric analysis (color, flavor and overall acceptability) was performed at different storage intervals for experimental treatments. RESULTS: The percent values of TPC yield from cabbage leave and banana peel samples ranged from a from minimum value of 9.8 ± 0.12% to a maximum value of 19.8 ± 0.15% for cabbage leaves and minimum value of 15.55 ± 0.13% to a maximum value of 24.4 ± 0.17% for banana peels, respectively. The results revealed that extraction conditions significantly affect the TPC yield from cabbage leaves and banana peels. The cabbage leaves and banana peels contain up to 4.8% total phenolics, cyanogenic compounds (1.44 - 1.47 ± 0.14) and tannins (6.55-7.90 ± 0.22). Peroxide values (meqO2 /kg) of meat balls treated with TPC extracts at 4 °C were in the range of 1.31 ± 0.12 to 3.10 ± 0.20 while at - 18 °C ranged was found 1.31 ± 0.12 to 1.55 ± 0.17, respectively. Peroxide values of all the treatments increased at the end of second interval then decreased at the end of last storage interval. Peroxide values of all treatments were higher and significantly different at the beginning and the end of the storage period (p <  0.05). In a similar way, free fatty acids and moisture content values trend was recorded for all experimental treatments. Sensory scores of fish product samples for color, flavor and overall acceptability showed a significant difference in sensory scores at refrigeration temperatures where sensory scores of fish product samples decreased significantly (p <  0.05) throughout refrigeration storage. Whereas, the sensory scores at the - 18 °C shows the good sensory characteristics, relatively. CONCLUSIONS: Phenolic extracts containing antioxidant status can interact with free lipidperoxy or lipidoxy free radicals (formed in result of lipid oxidation) and hence stopping their further self-breakdown. Plant-based phenolic extracts can be used to decrease oxidation process and increase the shelf life of fish meat products. Additional studies should be undertaken to determine the maximal shelf life of food products supplemented with different plant-based polyphenol extracts and treatment of nutritional disorders through their absorption, metabolism and distribution pattern into biological tissues.

Cucurmin, anticancer, & antitumor perspectives: A comprehensive review.

Cucurmin, a naturally yellow component isolated from turmeric, ability to prevent various life-style related disorders. The current review article mainly emphasizes on different anticancer perspectives of cucurmin, i.e., colon, cervical, uterine, ovarian, prostate head and neck, breast, pulmonary, stomach and gastric, pancreatic, bladder oral, oesophageal, and bone cancer. It holds a mixture of strong bioactive molecule known as cucurminoids that has ability to reduce cancer/tumor at initial, promotion and progression stages of tumor development. In particular, these compounds block several enzymes required for the growth of tumors and may therefore involve in tumor treatments. Moreover, it modulates an array of cellular progressions, i.e., nitric oxide synthetase activity, protein kinase C activity, epidermal growth factor (EGF) receptor intrinsic kinase activity, nuclear factor kappa (NF-kB) activity, inhibiting lipid peroxidation and production of reactive oxygen species. However, current manuscript summarizes most of the recent investigations of cucurmin but still further research should be conducted to explore the role of curcumin to mitigate various cancers.

Bioactive compounds and health benefits of edible Rumex species-A review.

Medicinal and food plants as well as their bioactive fractions have been used by diverse human cultures since ancient times. These plants provide multiple health benefits because of the presence of a plethora of phytochemicals including phenylpropanoids, isoprenoids, alkaloids, sulphated compounds, peptides and polysaccharides that are responsible for various biological activities such as anticancer, antioxidant, antifungal, antibacterial, anti-dysenteric, anti-inflammatory, antiulcer, anti-hypertensive and anticoagulant properties. The genus Rumex includes edible and medicinal herbs belonging to buckwheat (Polygonaceae) family, consisting of about 200 species rich in phenylpropanoids and anthraquinones. Some Rumex species have exhibited health-promoting effects and have been used as traditional foods and herbal remedies, though a limited information has been documented on their specific biological properties. Therefore, this survey aimed at reviewing the Rumex species with documented biological activity, focusing on preclinical evidences on their efficacy and safety.

Farm to Consumer: Factors Affecting the Organoleptic Characteristics of Coffee. II: Postharvest Processing Factors.

The production and consumption of coffee are increasing despite the roadblocks to its agriculture and global trade. The unique, refreshing, and stimulating final cupping quality of coffee is the only reason for this rising production and consumption. Coffee quality is a multifaceted trait and is inevitably influenced by the way it is successively processed after harvesting. Reportedly, 60% of the quality attributes of coffee are governed by postharvest processing. The current review elaborates and establishes for the first time the relationship between different methods of postharvest processing of coffee and its varying organoleptic and sensory quality attributes. In view of the proven significance of each processing step, this review has been subdivided into three sections, secondary processing, primary processing, and postprocessing variables. Secondary processing addresses the immediate processing steps on the farm after harvest and storage before roasting. The primary processing section adheres specifically to roasting, grinding and brewing/extraction, topics which have been technically addressed more than any others in the literature and by industry. The postprocessing attribute section deals generally with interaction of the consumer with products of different visual appearance. Finally, there are still some bottlenecks which need to be addressed, not only to completely understand the relationship of varying postharvest processing methods with varying in-cup quality attributes, but also to devise the next generation of coffee processing technologies.

Effects of sesame seed extract as a natural antioxidant on the oxidative stability of sunflower oil.

Natural and de-novo biosynthesized phyto-compounds have gained much significance because of their non-controversial nutritional, health and safety benefits as compared with chemically synthesized commercially rivalry antioxidants. However, none of natural de-novo biosynthesized phyto-compounds has been commercially available and used in customary food business and processing. In this study, efficacy of sesame seed extracts (SSEs) in stabilizing sunflower oil during storage has been studied. Fine powder of sesame seed was extracted in different solvents. The results showed that significant differences in extractability of different solvents and maximum extraction yield (29.48%) were achieved with methanol. The antioxidant components and capability of different extracts were further investigated and evaluated via total phenolic contents, DPPH radical scavenging activity and ß-carotene/linoleic acid calorimetric assays respectively. Being highest in yield and antioxidant potential, methanolic extract was used; three different concentrations of SSE (500, 750, and 1000 µL) were added in 100 mL of sunflower oil to further evaluate its oxidative stability. Sensory and oxidative analysis of baked product from these groups was also evaluated.

In vitro anti-thrombotic and anti-coagulant properties of blacklip abalone (Haliotis rubra) viscera hydrolysate.

Abalone viscera contain sulphated polysaccharides with anti-thrombotic and anti-coagulant activities. In this study, a hydrolysate was prepared from blacklip abalone (Haliotis rubra) viscera using papain and bromelain and fractionated using ion exchange and size exclusion chromatography. Hydrolysates and fractions were investigated for in vitro thrombin inhibition mediated through heparin cofactor II (HCII) as well as anti-coagulant activity in plasma and whole blood. On the basis of sulphated polysaccharide concentration, the hydrolysate inhibited thrombin through HCII with an inhibitor concentration at 50% (IC50) of 16.5 µg/mL compared with 2.1 µg/mL for standard heparin. Fractionation concentrated HCII-mediated thrombin inhibition down to an IC50 of 1.8 µg/mL and improved anti-coagulant activities by significantly delaying clotting time. This study confirmed the presence of anti-thrombotic and anti-coagulant molecules in blacklip abalone viscera and demonstrated that these activities can be enriched with a simple chromatography regime. Blacklip abalone viscera warrant further investigation as a source of nutraceutical or functional food ingredients. Graphical abstract Schematic showing preparation of bioactive extracts and fractions from blacklip abalone.

Anti-Coagulant and Anti-Thrombotic Properties of Blacklip Abalone (Haliotis rubra): In Vitro and Animal Studies.

Sulphated polysaccharides with anti-thrombotic and anti-coagulant activities have been found in various marine biota. In this study, a previously characterised anti-thrombotic and anti-coagulant extract from blacklip abalone was fractionated by anion exchange chromatography (AEC), pooled (on a sulphated polysaccharide basis) and administered to Wistar rats via oral gavage (N = 8) for assessment as an oral therapeutic. To ensure that the preparation had anti-coagulant activity prior to oral administration, it was assessed in rat blood by thromboelastography (TEG) significantly increasing reaction (R) time (or time until clot formation). Following in vitro confirmation of anti-coagulant activity, 40 mg of the preparation was orally administered to rats with blood samples collected at 2, 4, and 6 h post-gavage. Assessment of all blood samples by TEG showed some prolongation of R time from 355 to 380 s after 4 h. Dosing of the post-gavage blood samples with the abalone preparation to confirm anti-thrombotic activity in vitro revealed residual anti-coagulant activity, further suggesting that oral administration did increase anti-coagulant potential in the collected blood but that bioavailability was low. Assessment of tissues and haematological parameters showed no obvious harmful effects of the abalone preparation in animals. In summary, even though oral administration of fractionated and pooled blacklip abalone extract to rats delayed clotting after 4 h, bioavailability of the preparation appeared to be low and may be more appropriate for intravenous administration as an anti-thrombotic or anti-coagulant therapeutic.

In vitro Anti-Thrombotic Activity of Extracts from Blacklip Abalone (Haliotis rubra) Processing Waste.

Waste generated from the processing of marine organisms for food represents an underutilized resource that has the potential to provide bioactive molecules with pharmaceutical applications. Some of these molecules have known anti-thrombotic and anti-coagulant activities and are being investigated as alternatives to common anti-thrombotic drugs, like heparin and warfarin that have serious side effects. In the current study, extracts prepared from blacklip abalone (Haliotis rubra) processing waste, using food grade enzymes papain and bromelain, were found to contain sulphated polysaccharide with anti-thrombotic activity. Extracts were found to be enriched with sulphated polysaccharides and assessed for anti-thrombotic activity in vitro through heparin cofactor-II (HCII)-mediated inhibition of thrombin. More than 60% thrombin inhibition was observed in response to 100 µg/mL sulphated polysaccharides. Anti-thrombotic potential was further assessed as anti-coagulant activity in plasma and blood, using prothrombin time (PT), activated partial thromboplastin time (aPTT), and thromboelastography (TEG). All abalone extracts had significant activity compared with saline control. Anion exchange chromatography was used to separate extracts into fractions with enhanced anti-thrombotic activity, improving HCII-mediated thrombin inhibition, PT and aPTT almost 2-fold. Overall this study identifies an alternative source of anti-thrombotic molecules that can be easily processed offering alternatives to current anti-thrombotic agents like heparin.