Anticoagulant effect of Feijoa sellowiana extracts generated by different biotechnological techniques.

Blood clotting has become one of the most dangerous side effects associated with Corona virus, as well as the high level of cholesterol and triglycerides in the blood. Therefore, it has become necessary to use medicinal plants that are biologically safe and containing anti-clotting compound. Feijoa sellowiana represents a prolific source diverse compounds that may have thrombolytic activity. Therefore, the main research point is the production and scaling up of a target contents that have anticoagulants by using biotechnological techniques; calli production, and bioreactors and assessed their activity through in-vivo study. Murashige and Skoog (MS) medium enriched with varying concentrations of benzyl adenine (BA) and naphthalene acetic acid (NAA) was used to cultivate calli and cell suspension cultures from F. sellowiana seeds. Bioreactors were employed to boost active constituent's production. Moreover, the bioreactor physical factors such as effect of controlled or uncontrolled pH medium were investigated. The leaves of the main plant were extracted by ethanol 70% and polar and non-polar extracts were also prepared. The ethanol extract of calli and cells resulting from bioreactors were also prepared. All prepared extracts were subjected to chemical analysis by HPLC, in-vitro antioxidant assays, in-vivo anticoagulant activity and histopathological examination. Calli and cell suspension cultures were produced by using MS medium fortified with 1 mg/L BA+ 0.1 mg/L NAA. It was found that culturing of cell cultures in a bioreactor with uncontrolled pH and aeration at the value of 0.5 L/min gave the maximum and economical fresh and dry weights of the plants. After evaluation of all extracts; it was found that the calli ethanol extract for each plant was the highest value of total phenolic and total flavonoid contents either quantitatively or qualitatively. All extracts of Feijoa had antioxidant activity. The IC50 of the DPPH of Feijoa calli extract was 13.45 µg/mL, it was also confirmed by FRAP and ABTs values. Feijoa calli extract decreased platelet aggregation by suppression of thrombin, extended aPTT, PT, bleeding and clotting times. It was safer than warfarin medication. From these findings the authors can conclude that Feijoa had highly anticoagulant activity and the calli production achieved the goal of the enhancement of the phenolic constituent and thus their activity.

A Review of 3D Polymeric Scaffolds for Bone Tissue Engineering: Principles, Fabrication Techniques, Immunomodulatory Roles, and Challenges.

Over the last few years, biopolymers have attracted great interest in tissue engineering and regenerative medicine due to the great diversity of their chemical, mechanical, and physical properties for the fabrication of 3D scaffolds. This review is devoted to recent advances in synthetic and natural polymeric 3D scaffolds for bone tissue engineering (BTE) and regenerative therapies. The review comprehensively discusses the implications of biological macromolecules, structure, and composition of polymeric scaffolds used in BTE. Various approaches to fabricating 3D BTE scaffolds are discussed, including solvent casting and particle leaching, freeze-drying, thermally induced phase separation, gas foaming, electrospinning, and sol-gel techniques. Rapid prototyping technologies such as stereolithography, fused deposition modeling, selective laser sintering, and 3D bioprinting are also covered. The immunomodulatory roles of polymeric scaffolds utilized for BTE applications are discussed. In addition, the features and challenges of 3D polymer scaffolds fabricated using advanced additive manufacturing technologies (rapid prototyping) are addressed and compared to conventional subtractive manufacturing techniques. Finally, the challenges of applying scaffold-based BTE treatments in practice are discussed in-depth.

Development of Lepidium sativum Extracts/PVA Electrospun Nanofibers as Wound Healing Dressing.

Lepidium sativum L. (Garden cress/Hab El Rashad) (Ls), family Brassicaceae, has considerable importance in traditional medicine worldwide because of its antioxidant and anti-inflammatory activities. Ls fruits were used in Ayurvedic medicines as a useful drug for injuries, skin, and eye diseases. The aim of this study was to examine the effectiveness of the total ethanol extract (TEE) and polysaccharide (Poly) of Ls seeds loaded on poly(vinyl alcohol) (PVA) nanofibers (NFs) as a wound healing dressing and to correlate the activity with the constituents of each. TEE and Poly were phytochemically analyzed qualitatively and quantitatively. Qualitative analysis proved the presence of phenolic acids, flavonoids, tannins, sterols, triterpenes, and mucilage. Meanwhile, quantitative determinations were carried out spectrophotometrically for total phenolic and total flavonoid contents. High-performance liquid chromatography (HPLC) for TEE identified 15 phenolic acids and flavonoid compounds, with gallic acid and catechin as the majors. Separation, purification, and identification of the major compounds were achieved through a Puriflash system, column Sephadex LH20, and spectroscopic data (1H, 13C NMR, and UV). Eight compounds (gallic acid, catechin, rutin, kaempferol-3-O-rutinoside, quercetin-3-O-rhamnoside, kaempferol-3-O-rhamnoside, quercetin, and kaempferol) were obtained. Gas-liquid chromatography (GLC) analysis for Poly identified 11 compounds, with galactose being the main. The antioxidant activity for both extracts was measured by three different methods based on different mechanisms: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing ability of plasma (FRAP), and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS). TEE has the highest effectiveness as an antioxidant agent with IC50 82.6 ± 8.35 µg/mL for DPPH and 772.47 and 758.92 µM Trolox equivalent/mg extract for FRAP and ABTS, respectively. The PVA nanofibers (NFs) for each sample were fabricated by electrospinning. The fabricated NFs were characterized by SEM and Fourier transform infrared spectroscopy (FTIR); the results revealed successful encapsulation of TEE and Poly in the prepared NFs. Moreover, the swelling index of TEE in the prepared NFs shows that it is the most appropriate for use as a wound dressing. Cytotoxicity studies indicated a high cell viability with IC50 216 µg/mL and 1750 µg/mL for TEE and Poly, respectively. Moreover, the results revealed that nanofibers possess higher cell viability compared to solutions with the same sample quantities: 9-folds for TEE and 4-folds for Poly of amount 400 µg. The in vitro wound healing test showed that the TEE nanofibers performed better than Poly nanofibers in accelerating wound healing, with 90% for TEE, more than that for the Poly extract (82%), after 48 h. These findings implied that the incorporation of TEE in PVA nanofibers was more efficient than incorporation of Poly in improving the biological activity in wound healing. In conclusion, the TEE and polysaccharides of L. sativum L seed are ideal candidates for nanofibrous wound dressings. Furthermore, the contents of phenolic acids and flavonoids in TEE, which have potential antioxidant activity, make the TEE of L. sativum more favorable for wound healing dressing.