Significant Anticoagulant Activity Research Articles

Potential Bioactivities, Chemical Composition, and Conformation Studies of Exopolysaccharide-Derived Aspergillus sp. Strain GAD7.

This research identified a marine fungal isolate, Aspergillus sp. strain GAD7, which produces an acidic and sulfated extracellular polysaccharide (EPS) with notable anticoagulant and antioxidant properties. Six fungal strains from the Egyptian Mediterranean Sea were screened for EPS production, with Aspergillus sp. strain GAD7 (EPS-AG7) being the most potent, yielding ~5.19 ± 0.017 g/L. EPS-AG7 was characterized using UV-Vis and FTIR analyses, revealing high carbohydrate (87.5%) and sulfate (24%) contents. HPLC and GC-MS analyses determined that EPS-AG7 is a heterogeneous acidic polysaccharide with an average molecular weight (Mw¯) of ~7.34 × 103 Da, composed of mannose, glucose, arabinose, galacturonic acid, galactose, and lyxose in a molar ratio of 6.6:3.9:1.8:1.3:1.1:1.0, linked through α- and β-glycosidic linkages as confirmed by NMR analysis. EPS-AG7 adopted a triple helix-like conformation, as evidenced by UV-Vis (Congo Red experiment) and circular dichroism (CD) studies. This helical arrangement demonstrated stability under various experimental conditions, including concentration, ionic strength, temperature, and lipid interactions. EPS-AG7 exhibited significant anticoagulant activity, doubling blood coagulation time at a concentration of 3.0 mg/mL, and showed significant antioxidant activity, with scavenging activities reaching up to 85.90% and 58.64% in DPPH and ABTS+ assays at 5.0 mg/mL, and EC50 values of 1.40 mg/mL and 3.80 mg/mL, respectively. These findings highlight the potential of EPS-AG7 for therapeutic applications due to its potent biological activities.

Structure and anticoagulant activity of a galactoarabinan sulfate polysaccharide and its oligosaccharide from the green algae, Codium fragile

A polysaccharide, CZS-0-1, was obtained from the marine green algae Codium fragile using ion-exchange and size-exclusion chromatography. Composition and characteristics analyses showed CZS-0-1 was a sulfated galactoarabinan consisting of arabinose, galactose and a small amount of glucose in a ratio of 9:2:1 with 21% sulfate content and a molecular weight of 810 kDa. Structural properties were determined using desulfation and methylation analyses combined with instrument analysis. The results showed that the backbone of CZS-0-1 was (1 → 3)-β-L-Arap. Its O-4 and/or O-2 positions showed sulfate modification; additionally, it had 10% of (1 → 3)-β-D-Galp branches at the O-4 position of the (1 → 3)-β-L-Arap. The galactose side chains also had sulfate modification at the O-4 or O-6 position. The structure of CZS-0-1 was further confirmed by Top-down analysis of the oligosaccharides after oxidated hydrolysis by mass spectrometry. CZS-0-1 exhibited significant heparin-like anticoagulant activity. It exerted anticoagulant effects by inhibiting FIIa and FXa activities with the presence of heparin cofactors. The anticoagulant activity of CSZ-0-1 was closely related to the molecular weight, and the reduction of molecular weight may lead to a significant decrease in the anticoagulant activity. This study demonstrated that the green algae, Codium fragile can be considered as a useful resource for bioactive polysaccharides.

Serological Evaluation of the Anti-coagulant Activity of the Classical Siddha Medicine -‘Veera Mezhugu’ in Wistar Albino Rats

In setting the basis for the management of arterial thrombosis, cardiac ischemic changes followed by any severe coronary atherosclerotic changes or any venous thrombosis, there is a conventional use of Acute thrombolytic agents, Anticoagulants with antiplatelet medications in general. These symptoms complex are mentioned as Thamaraga vaayu or Ruththira vaayu or Maaradaippu(Acute coronary syndrome) and Uthirakattu(thromboembolism) in siddha literatures. Veera mezhugu is one of the Siddha formulations chosen from Anuboga vaithiya navaneetham part-4, which is indicated for Uthirakattu and Thamaragavaayu. The drug prepared as per the Siddha literature. The drug has undergone safety studies and the efficacy studies in Wistar albino rats where the serum of the different groups with different doses are compared with the placebo control to evaluate the anti-coagulant potential. Coagulation profile of the three parameters of Activated partial thromboplastin time(APTT), Prothrombin time(PT) and International normalized ratio(INR) are taken for evaluation and had significant difference between the groups[p<0.05].Serological analysis of the Wistar rats shows significant anticoagulant activity in a dose dependent manner.

A Review on “The In-vitro Study of Anticoagulant Activity of Different Plant Extract”

The aim of this review is to evaluate the plant extract which show highest anticoagulant activity. There are different plant extract to show the anticoagulant activity. On the basis of this study to know about which plant show maximum anticoagulant activity and which plant has minimum anticoagulant activity. The plants used are naturally obtained. They have other pharmacological properties but some plant have significant anticoagulant activity. The plant used for studied are Myrciaria plinioides, Terminalia bellerica, Gymnema sylvestre, Jatropa gossypiifolia, Allium sativum , Curcuma longa,Rubus ulmifolius, Gymnema sylvestre. Among these plant the Gymnema sylvestre has maximum anticoagulant activity, and the other plant show a significant anticoagulant activity. The prothrombin test, activated prothrombin test , thrombin test, recalcification method were used for the in vitro test of anticoagulant activity. The extract of plant were obtained by various extraction process such as maceration, soxhlet extraction, decoction method etc.

Green fabrication of ZnO nanoparticles via spirulina platensis and its efficiency against biofilm forming pathogens

Excessive consumption of antibiotics is considered one of the top public health threats, this necessitates the development of new compounds that can hamper the spread of infections. A facile green technology for the biosynthesis of Zinc oxide nanoparticles (ZnO NPs) using the methanol extract of Spirulina platensis as a reducing and stabilizing agent has been developed. A bunch of spectroscopic and microscopic investigations confirmed the biogenic generation of nano-scaled ZnO with a mean size of 19.103 ± 5.66 nm. The prepared ZnO NPs were scrutinized for their antibacterial and antibiofilm potentiality, the inhibition zone diameters ranged from 12.57 ± 0.006 mm to 17.33 ± 0.006 mm (at 20 µg/mL) for a variety of Gram-positive and Gram-negative pathogens, also significant eradication of the biofilms formed by Staphylococcus aureus and Klebsiella pneumoniae by 96.7% and 94.8% respectively was detected. The free radical scavenging test showed a promising antioxidant capacity of the biogenic ZnO NPs (IC50=78.35 µg/mL). Furthermore, the anti-inflammatory role detected using the HRBCs-MSM technique revealed an efficient stabilization of red blood cells in a concentration-dependent manner. In addition, the biogenic ZnO NPs have significant anticoagulant and antitumor activities as well as minimal cytotoxicity against Vero cells. Thus, this study offered green ZnO NPs that can act as a secure substitute for synthetic antimicrobials and could be applied in numerous biomedical applications.

Thrombin-targeted screening of anticoagulant active components from Polygonum amplexicaule D. Don var. sinense Forb by affinity ultrafiltration coupled with UPLC-Q-TOF-MS.

Polygonum amplexicaule D. Don var. sinense Forb (PAF), a medicinal plant, has the effect of promoting blood circulation and removing blood stasis. However, the active compounds and targets of its anticoagulant effect are still unclear. This study aims to establish an effective reversely thrombin-targeted screening method for anticoagulant active components in PAF by affinity ultrafiltration (AUF) coupled with ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectroscopy (UPLC-Q-TOF-MS). Different polar parts of PAF were screened for potential thrombin ligands by AUF-HPLC and identified by UPLC-Q-TOF-MS. After studying the affinity between ligands and thrombin by molecular docking, the antithrombotic activity of ligands was detected in vivo by zebrafish thrombus model, and in vitro by chromogenic substrate method. The mechanism of such ligands on thrombin was further studied by coagulation factor assay. Eleven potential thrombin ligands from PAF were screened by the AUF-UPLC-Q-TOF-MS method, and two compounds (butyl gallate and β-sitosterol) with significant anticoagulant activity were discovered via in vitro and in vivo activity testing. A method system based on AUF-UPLC-Q-TOF-MS, molecular docking and in vivo and in vitro experiments also provided a powerful tool for further exploration of anticoagulant active components in PAF.

Anti-hemostatic, antithrombotic, and chemical profiles of a curly-leaf variety of Petroselinum crispum (Apiaceae), a food and medicinal aromatic herb

Thrombosis is currently among the major causes of morbidity and mortality in the World. New prevention and therapy alternatives have been increasingly sought in medicinal plants. In this context, we have been investigating parsley, Petroselinum crispum (Mill.) Nym, an aromatic herb with two leaf varieties. We report here the in vitro, in vivo, and ex vivo anti-hemostatic and antithrombotic activities of a parsley curly-leaf variety. Aqueous extracts of aerial parts (PCC-AP), stems (PCC-S), and leaves (PCC-L) showed significant in vitro antiplatelet activity. PCC-AP extract exhibited the highest activity (IC50 2.92 mg/mL) when using ADP and collagen as agonists. All extracts also presented in vitro anticoagulant activity (APTT and PT) and anti-thrombogenic activity. PCC-S was the most active, with more significant interference in the factors of the intrinsic coagulation pathway. The oral administration of PCC-AP extract in rats caused a greater inhibitory activity in the deep vein thrombi (50%; 65 mg/kg) than in arterial thrombi formation (50%; 200 mg/kg), without cumulative effect after consecutive five-day administration. PCC-AP extract was safe in the induced bleeding time test. Its anti-aggregating profile was similar in ex vivo and in vitro conditions but was more effective in the extrinsic pathway when compared to in vitro results. Apiin and coumaric acid derivatives are the main compounds in PCC-AP according to the HPLC-DAD-ESI-MS/MS profile. We demonstrated for the first time that extracts from different parts of curly parsley have significant antiplatelet, anticoagulant, and antithrombotic activity without inducing hemorrhage, proving its potential as a source of antithrombotic compounds.

New steroidal saponins from the aerial parts of Paris polyphylla var. yunnanensis and their effects on blood coagulation

Five new steroidal saponins, paripolins D-H (1–5), and 6 known compounds (6–11) were isolated from the aerial parts of Paris polyphylla var. yunnanensis. The structures of 1–5 were determined using spectroscopic analyses in conjunction with acid hydrolysis. It is for the first time to report the 12-hydroxysteroidal saponins from the genus Paris. The effect of all isolated compounds on blood coagulation was determined in vitro using the plasma recalcification time method. Compounds 1 and 2 showed potent procoagulant activity, and 5–11 exhibited significant anticoagulant activity.

Anticoagulant Evaluation of Momordica charantia Fruit Flesh Extract on Prothrombin Time and Activated Partial Prothrombin Time Test

Thrombotic diseases such as strokes, deep vein thrombosis (DVT), pulmonary embolism are serious consequences of the thrombus formed in blood vessels. The coagulation cascade is a complicated system that involves clotting factor of extrinsic, intrinsic, and common pathways. Imbalance between the process can cause excessive clotting that led to thrombosis. Although several anticoagulants drugs have been developed over the decades, most are accompanied by undesirable side effects such as mild or severe bleeding. Therefore, this study has made use of the natural resources in the search for complementary and alternative therapies. The methanolic extract of Momordica charantia (MC) (bitter gourd) fruit flesh is utilized to identify their effects through in vitro anticoagulant and thrombolytic activity. The anticoagulant activity is tested using prothrombin time (PT) and activated partial prothrombin time (APTT) test with 10, 20 and 30 mg/ml of MC extraction, while the thrombolytic activity is carried out by using clot lysis assay. Momordica charantia fruit flesh methanolic extract was proven to have significant anticoagulant properties at concentration 20 and 30 mg/ml compared to normal and negative control. The extract however was not significant at 10 mg/ml but still demonstrated some anticoagulation effect. It also revealed a substantial thrombolytic activity at 100 mg/ml, when compared to negative and positive control indicating ability to lyse blood clot. It was discovered by our analysis that Momordica charantia fruit flesh possesses significant anticoagulant and thrombolytic activity which can be further exploited in the treatment of blood coagulation disorder.

Antihyperglycemic, Neuropharmacological, Cytotoxic, Anticoagulant, and Anti-inflammatory Pharmacological Evaluations of Vernonia elaeagnifolia DC Leaves Secondary Bioactive Metabolites

The current investigation was carried out to confirm the antihyperglycemic, cytotoxic, neuropharmacological, anticoagulant, and anti-inflammatory effects of the ethanolic extract of Vernonia elaeagnifolia leaves in different experimental models. In the oral glucose tolerance test, the plant extract demonstrated significant (p < 0.05) antihyperglycemic activity by reducing the elevated blood glucose level in mice at both doses (250 mg/kg and 500 mg/kg) when compared to the control groups. The crude ethanolic leaf extract, however, didn’t afford to block the α-glucosidase enzyme up to 0.5 mg/mL. The experimental mice showed a noticeable (p <0.001) decrease in locomotor and exploratory activities in the hole cross and open field tests, as well as head dipping in the hole-board test model in the neuropharmacological activity assay at both doses (250 mg/kg and 500 mg/kg). The extracts also showed cytotoxic activity in a brine shrimp lethality bioassay with an LC50 of 91.929 μg/mL and showed significant concentration-dependent anticoagulant activity (p<0.001). Moreover, the extract (10–500 mg/kg) caused a significant (P<0.01 – 0.001) dose-dependent reduction of inflammation induced in rats by using two different models: formalin-induced paw edema and egg-albumin-induced paw edema. From the above results, the crude extract of V. elaeagnifolia DC leaves have significant pharmacological potential in different in vitro and in vivo study model. So, it could be a source of a substance for isolating lead that could be used to treat several diseases.

<i>In vitro</i> Characterization of the Essential Oil Extracted from <i>Lavandula dentata</i> and its Application in the Field of Biotherapy.

<b>Background and Objective:</b> <i>Lavandula dentata </i>essential oil holds promise as a valuable natural resource with diverse therapeutic potential. The main objective of this study was to investigate the bioactivities of <i>Lavandula dentata </i>essential oil, specifically its antimicrobial, analgesic, anti-diabetic and anticoagulant properties. <b>Materials and Methods:</b> The Algerian medicinal plant <i>Lavandula dentata </i>EO was collected from Tipaza City (Algeria). The hydro-distillation method was used to get yield of essential oil. The GC/MS analysis was done to identify the bioactive compound of <i>Lavandula dentata</i> EO. The antimicrobial activity of<i> L. dentata </i>essential oil (EO) was assessed using the disc diffusion method against eight different microorganisms. The antidiabetic and anticoagulant activity was also studied. <b>Results:</b> The hydrodistillation method yielded approximately 0.4% of essential oil. The GC/MS results showed that <i>L. dentata</i> EO contains a total of 18 elements and the main constituents were 1.8-cineole (41.48%) and β-pinene (33.43%). The EO exhibited a robust inhibitory effect on the growth of all tested microorganisms, with inhibitory diameters ranging from 16.6 to 38.5 mm. <i>Lavandula dentata</i> EO presented anti-diabetic activity by inhibiting the α-amylase enzyme, with an IC<sub>50</sub> value of approximately 135.08±0.25 μg mL<sup>–1</sup>, demonstrating significant anti-diabetic activity and anti-coagulant activity. <b>Conclusion:</b> <i>Lavandula dentata</i> EO processes great antimicrobial, analgesic, anti- diabetic and anticoagulant properties. Further investigations into its mechanisms of action and safety profile are warranted to fully exploit its therapeutic potential.

Structure and Anticoagulant Activity of a Galactofuranose-Containing Sulfated Polysaccharide from the Green Seaweed, Codium isthmocladum.

A water-soluble sulfated polysaccharide, F2-1, was obtained from the marine green alga, Codium isthmocladum, using ion-exchange and size-exclusion chromatography. Structure analysis showed that the F2-1 was a sulfated arabinan comprising Ara, Rha, Man, Gal, and Xyl with an 18% sulfate content and a molecular weight of 100 kDa. Methylation analysis combined with desulfation, GC-MS, IR, and NMR spectroscopy showed that the backbone of F2-1 was →4)-β-L-Arap(1→ residue. Its 2-O and/or 3-O positions showed sulfate modification; additionally, the 2-O or 3-O position showed branch points. The side chains were composed of →5)-β-D-Galf, (1→2,6)-β-D-Galf(1→, (1→2)-β-L-Rhap4S, →4)-α-D-Glcp(1→, and terminal α-D-Galp(1→ and β-D-Xylp(1→. Polysaccharides containing β-D-galactofuranose are rarely found in seaweed. F2-1 exhibited significant anticoagulant activity in vitro. Our findings suggested that the green-tide alga, Codium isthmocladum, can be considered as a useful resource for bioactive polysaccharides.

Subchronic Toxicity Study of Alternanthera philoxeroides in Swiss Albino Mice Having Antioxidant and Anticoagulant Activities.

Alternanthera philoxeroides, a tropical herb and edible vegetable, has been popular as a medicinal plant. Applying in vitro approach, we initially attempted to assess the phytochemicals, bioactive chemicals, as well as antioxidant and anticoagulant activities of this plant. Following that, the in vivo toxicological effects of methanolic extracts of A. philoxeroides using different doses on the kidney, heart, lung, liver, stomach, brain, and blood of female Swiss Albino mice were investigated. We estimated phytochemicals content as well as antioxidant activity through DPPH, NO, CUPRAC, and reducing power assays, followed by the anticoagulant activities of PT and aPTT and bioactive compounds using HPLC. To confirm the biocompatibility of A. philoxeroides extracts, histopathological and hematological parameters were examined in a mice model. Total phenol, flavonoid, and tannin content in A. philoxeroides was 181.75 ± 2.47 mg/g, 101.5 ± 3 .53 mg/g, and 68.58 ± 0.80 mg/g, respectively. Furthermore, the HPLC study confirmed the presence of four phenolic compounds: catechin, tannic acid, gallic acid, and vanillic acid. The methanolic extract of A. philoxeroides showed considerable antioxidant activity in all four antioxidant assay methods when compared to the standard. In comparison to ascorbic acid, A. philoxeroides also demonstrated a minor concentration-dependent ferric and cupric reduction activity. In vivo evaluation indicated that A. philoxeroides extracts (doses: 250, 500, and 1000 mg/kg) had no negative effects on the relative organ or body weight, or hematological indicators. Our study concluded that A. philoxeroides had significant antioxidant and anticoagulant activities and demonstrated no negative effects on the body or relative organ weight, histopathological, and hematological indices in the mouse model.

Fucose-Rich Sulfated Polysaccharides from Two Vietnamese Sea Cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera: Structures and Anticoagulant Activity.

Fucosylated chondroitin sulfates (FCSs) FCS-BA and FCS-HS, as well as fucan sulfates (FSs) FS-BA-AT and FS-HS-AT were isolated from the sea cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera, respectively. Purification of the polysaccharides was carried out by anion-exchange chromatography on DEAE-Sephacel column. Structural characterization of polysaccharides was performed in terms of monosaccharide and sulfate content, as well as using a series of non-destructive NMR spectroscopic methods. Both FCSs were shown to contain a chondroitin core [→3)-β-d-GalNAc-(1→4)-β-d-GlcA-(1→]n bearing sulfated fucosyl branches at O-3 of every GlcA residue in the chain. These fucosyl residues were different in pattern of sulfation: FCS-BA contained Fuc2S4S, Fuc3S4S and Fuc4S at a ratio of 1:8:2, while FCS-HS contained these residues at a ratio of 2:2:1. Polysaccharides differed also in content of GalNAc4S6S and GalNAc4S units, the ratios being 14:1 for FCS-BA and 4:1 for FCS-HS. Both FCSs demonstrated significant anticoagulant activity in clotting time assay and potentiated inhibition of thrombin, but not of factor Xa. FS-BA-AT was shown to be a regular linear polymer of 4-linked α-L-fucopyranose 3-sulfate, the structure being confirmed by NMR spectra of desulfated polysaccharide. In spite of considerable sulfate content, FS-BA-AT was practically devoid of anticoagulant activity. FS-HS-AT cannot be purified completely from contamination of some FCS. Its structure was tentatively represented as a mixture of chains identical with FS-BA-AT and other chains built up of randomly sulfated alternating 4- and 3-linked α-L-fucopyranose residues.

Bioengineering of green-synthesized silver nanoparticles: In vitro physicochemical, antibacterial, biofilm inhibitory, anticoagulant, and antioxidant performance

Green-synthesized nanobiomaterials can be engineered as smart nanomedicine platforms for diagnostic and therapeutic purposes in medicine. Herein, we investigated the bioengineering of silver nanoparticles (AgNPs) and evaluated their physicochemical, antibacterial, biofilm inhibitory, anticoagulant, and antioxidant performance. Characterization of the AgNPs was performed utilizing UV–visible, transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FT-IR). The spherical shaped AgNPs were proven by TEM and SEM techniques. Moreover, the XRD diffraction patterns demonstrated that the nanoparticles were in a crystalline state. The DLS represented the hydrodynamic particle size of the NPs at 49.62 nm at a pH of 9. The calculated minimum inhibitory concentration (MIC) of AgNPs toward Staphylococcus aureus (ATCC 25923) was 8 μg mL−1, which was almost similar to tetracycline by the value of 4 μg mL−1. Moreover, the minimum bactericidal concentration (MBC) of AgNPs was 64 μg mL−1, which was significantly less than the determined value of 256 μg mL−1 for tetracycline. Considering the pathogenic and standard S. aureus, the evaluated concentrations of AgNPs and tetracycline showed significant biofilm inhibitory performance. Furthermore, the bioengineered AgNPs exhibited significant anticoagulant activity at 500 μg mL−1 compared to saline (P < 0.001). In addition, the biogenic AgNPs inhibited 69.73 ± 0.56% of DPPH free radicals at 500 μg mL−1, indicating considerable antioxidant potential.

Targeting the S2 Subsite Enables the Structure-Based Discovery of Novel Highly Selective Factor XIa Inhibitors.

FXIa inhibition has been a promising strategy for treating thrombotic diseases. Up to date, many small-molecule FXIa inhibitors have been identified; however, most of them exhibit undesirable selectivity over the homologous plasma kallikrein (PKal). By employing structure-based drug design strategies, we identified many novel selective FXIa inhibitors that have extra interactions with the S2 subsite of FXIa. Among them, compound 35 displayed good inhibitory activity against FXIa and high selectivity over PKal and even several other serine proteases. Additionally, 35 showed significant anticoagulant activity toward the intrinsic pathway without affecting the extrinsic pathway. In vivo, 35 exhibited significant antithrombotic activity without increasing the bleeding risk and obvious toxicity in mice, demonstrating that it could be a promising candidate for further research. This study first demonstrates the importance of the S2 subsite of FXIa, paving the way to design highly selective FXIa inhibitors for clinical uses.

Lignosulfonic Acid Sodium Is a Noncompetitive Inhibitor of Human Factor XIa.

The anticoagulant activity of lignosulfonic acid sodium (LSAS), a non-saccharide heparin mimetic, was investigated in this study. LSAS is a relatively safe industrial byproduct with similar polyanionic characteristics to that of heparin. Human plasma clotting assays, fibrin polymerization testing, and enzyme inhibition assays were exploited to investigate the anticoagulant activity of LSAS. In normal human plasma, LSAS selectively doubled the activated partial thromboplastin time (APTT) at ~308 µg/mL. Equally, LSAS doubled APTT at ~275 µg/mL in antithrombin-deficient plasma. Yet, LSAS doubled APTT at a higher concentration of 429 µg/mL using factor XI-deficient plasma. LSAS did not affect FXIIIa-mediated fibrin polymerization at 1000 µg/mL. Enzyme assays revealed that LSAS inhibits factor XIa (FXIa) with an IC50 value of ~8 μg/mL. LSAS did not inhibit thrombin, factor IXa, factor Xa, factor XIIIa, chymotrypsin, or trypsin at the highest concentrations tested and demonstrated significant selectivity against factor XIIa and plasmin. In Michaelis–Menten kinetics, LSAS decreased the VMAX of FXIa hydrolysis of a tripeptide chromogenic substrate without significantly changing its KM indicating an allosteric inhibition mechanism. The inhibitor also disrupted the generation of FXIa–antithrombin complex, inhibited factor XIIa-mediated and thrombin-mediated activation of the zymogen factor XI to FXIa, and competed with heparin for binding to FXIa. Its action appears to be reversed by protamine sulfate. Structure–activity relationship studies demonstrated the advantageous selectivity and allosteric behavior of LSAS over the acetylated and desulfonated derivatives of LSAS. LSAS is a sulfonated heparin mimetic that demonstrates significant anticoagulant activity in human plasma. Overall, it appears that LSAS is a potent, selective, and allosteric inhibitor of FXIa with significant anticoagulant activity in human plasma. Altogether, this study introduces LSAS as a promising lead for further development as an anticoagulant.

Polyphenol Rich Ajuga bracteosa Transgenic Regenerants Display Better Pharmacological Potential.

Ajuga bracteosa Wall. ex Benth. is an endangered medicinal herb traditionally used against different ailments. The present study aimed to create new insight into the fundamental mechanisms of genetic transformation and the biological activities of this plant. We transformed the A. bracteosa plant with rol genes of Agrobacterium rhizogenes and raised the regenerants from the hairy roots. These transgenic regenerants were screened for in vitro antioxidant activities, a range of in vivo assays, elemental analysis, polyphenol content, and different phytochemicals found through HPLC. Among 18 polyphenolic standards, kaempferol was most abundant in all transgenic lines. Furthermore, transgenic line 3 (ABRL3) showed maximum phenolics and flavonoids content among all tested plant extracts. ABRL3 also demonstrated the highest total antioxidant capacity (8.16 ± 1 μg AAE/mg), total reducing power, (6.60 ± 1.17 μg AAE/mg), DPPH activity (IC50 = 59.5 ± 0.8 μg/mL), hydroxyl ion scavenging (IC50 = 122.5 ± 0.90 μg/mL), and iron-chelating power (IC50 = 154.8 ± 2 μg/mL). Moreover, transformed plant extracts produced significant analgesic, anti-inflammatory, anticoagulant, and antidepressant activities in BALB/c mice models. In conclusion, transgenic regenerants of A. bracteosa pose better antioxidant and pharmacological properties under the effect of rol genes as compared to wild-type plants.

Anticoagulant Activity of Sulfated Polysaccharides and Polyphenols Extracted from Marine Algae

Background: Recent studies have provided evidence that marine algae sulfated polysaccharides and phlorotannins play an important role in human health. The aim of this study was to evaluate the anticoagulant activity of five marine algae extracts from Bejaia’s coast (Algeria). Methods: Phenolic and sugar contents of the five marine algae were assessed using folin ciocalteu and anthrone reagents, respectively. The anticoagulant activity was evaluated by the Activated Partial Thromboplastin Time (APTT) and Prothrombin Time (PT). Results: Higher contents of phenolic compounds were obtained with ethanol for Cystoseira humilis, Halopteris scoparia, Padina pavonica, and Rhodomela confervoides (8.55±0.29, 7.84±0.47, 6.41±0.14 and 4.16±0.04 mg CE/g of dw, respectively). Whereas, for Sargassum vulgare, the extraction with acetone showed higher content (3.04±0.071 mg CE/g of dw). The determination of sugar content showed that acetone extract of the five seaweeds was the richest in sugar, this rate increasingly dropped in ethanol extract and the fractions A and B. The red algae Rhodomela confervoides showed a significant anticoagulant activity in ethanol extract and the fractions A, B, and C, with elongation up to 407.97±58.12 s in the fraction C, at a concentration of 10 mg/mL. Anticoagulant activity was observed in the fractions A, B, and C of all the brown seaweeds. Procoagulant activity was observed in the fractions A and B of Cystoseira humilis and Sargassum vulgare, as well as the fraction B of Padina pavonica for an indeterminate period, at 10 mg/mL. Conclusion: The sulfated polysaccharides present in the fractions A, B and C of the studied marine algae may be responsible for the anticoagulant activity. So, they can be developed as a novel anticoagulant in the pharmaceutical industry.

A regular fucan sulfate from Stichopus herrmanni and its peroxide depolymerization: Structure and anticoagulant activity

Marine sulfated polysaccharides have aroused widespread concern for their various structures and bioactivities. Peroxide depolymerization is a common strategy in analysis of structures and structure-activity relationships of polysaccharides. However, confirming the depolymerization process and exact structures of the degradation products is still a considerable challenge. This study reported the structures of a fucan sulfate (FS) from sea cucumber Stichopus herrmanni and its depolymerized products (dFS) prepared by peroxide degradation. The FS was elucidated with a highly regular structure, {-3)-L-Fuc2S-(α1-}n. Structure analysis of oligosaccharides purified from dFS suggested that peroxide degradation involved in cleavage of glycosidic bonds and oxidative modification of reducing end of sugar residue, while no break in sugar ring was observed. Both FS and series of dFSs exhibited significant anticoagulant activities due to their anti-thrombin effects in presence of heparin cofactor II and their potencies were related to their molecular sizes, dFS with ∼ 20 kDa showed the strongest activity.