scholarly journals Synthesis and Physico-Chemical Evaluation of Polyurethane Microstructures for Transmembrane Delivery of Reynoutria japonica Extract

2017 ◽  
Vol 54 (4) ◽  
pp. 651-654
Author(s):  
Florina Ardelean ◽  
Razvan Susan ◽  
Florin Borcan ◽  
Alina Moaca ◽  
Diana Simona Antal ◽  
...  

Polymer microstructures containing plant extracts are a novel technique used to increase the bioavailability of active agents with low aqueous solubility. Japanese knotweed (Reynoutria japonica) is an invasive plant with multiple biomedical properties. The aim of the present study was to obtain and characterize polyurethane microstructures used as a drug delivery system of a Japanese knotweed extract. The results indicate the obtaining of microstructures with an almost neutral pH, with sizes between 540 and 1134 nm, with a medium stability against the tendency to form clusters and a very good thermal stability. These first results present the potential of the obtained polyurethane microstructures as candidates for the transmembrane drug delivery of Japanese knotweed extracts, as a starting point for further bioactivity investigations.

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11783
Author(s):  
Jacob W. Lawson ◽  
Mark Fennell ◽  
Mark W. Smith ◽  
Karen L. Bacon

Reynoutria japonica (Japanese knotweed) is a problematic invasive plant found in many areas of Europe and North America. Notably, in the UK, the species can cause issues with mortgage acquisition. Control of R. japonica is complicated by its ability to regenerate from small fragments of plant material; however, there remains uncertainty about how much (in terms of mass) rhizome is required for successful regeneration. This study investigated the ability of crowns and rhizomes with different numbers of nodes to regenerate successfully from three sites in the north of England, UK. Two of the sites had been subject to herbicide treatment for two years prior to sampling and the third site had no history of herbicide treatment. No significant differences were observed in regenerated stem diameter, maximum height of stem and maximum growth increments among crowns. All traits measured from the planted crowns were significantly greater than those of the planted rhizome fragments and at least one node was necessary for successful regeneration of rhizomes. The smallest initial fragment weight to regenerate and survive the experiment was 0.5 g. Subjecting all plant material to desiccation for 38 days resulted in no regrowth (emergence or regeneration) after replanting. These findings suggest that desiccation could be a valuable management strategy for small to medium scale infestations common in urban settings.


NeoBiota ◽  
2020 ◽  
Vol 56 ◽  
pp. 89-110 ◽  
Author(s):  
François-Marie Martin ◽  
Fanny Dommanget ◽  
François Lavallée ◽  
André Evette

Many of the most invasive plant species in the world can propagate clonally, suggesting clonality offers advantages that facilitate invasion. Gaining insights into the clonal growth dynamics of invasive plants should thus improve understanding of the mechanisms of their dominance, resilience and expansion. Belonging to the shortlist of the most problematic terrestrial invaders, Reynoutria japonica var. japonica Houtt. (Japanese knotweed) has colonized all five continents, likely facilitated by its impressive ability to propagate vegetatively. However, its clonal growth patterns are surprisingly understudied; we still do not know how individuals respond to key environmental conditions, including light availability and disturbance. To contribute to filling this knowledge gap, we designed a mesocosm experiment to observe the morphological variation in R. japonica growth in homogeneous or heterogeneous conditions of light stress (shade) and disturbance (mowing). Rhizome fragments were planted in the middle of large pots between two habitat patches that consisted of either one or a combination of the following three environmental conditions: full light without mowing, full light with frequent mowing, or shade without mowing. At the end of the experiment, biomass and traits related to clonal growth (spacer and rhizome lengths, number of rhizome branches, and number of ramets) were measured. After 14 months, all individuals had survived, even those frequently mowed or growing under heavy shade. We showed that R. japonica adopts a ‘phalanx’ growth form when growing in full light and a ‘guerrilla’ form when entirely shaded. The former is characteristic of a space-occupancy strategy while the latter is more associated with a foraging strategy. In heterogeneous conditions, we also showed that clones seemed to invest preferentially more in favorable habitat patches rather than in unfavorable ones (mowed or shaded), possibly exhibiting an escape strategy. These observations could improve the management of this species, specifically by illustrating how aggressive early control measures must be, by highlighting the importance of repeated mowing of entire stands, as this plant appears to compensate readily to partial mowing, and by informing on its potential responses towards the restoration of a cover of competitive native plants.


Author(s):  
Vikrant P Wankhade ◽  
Nivedita S Kale ◽  
K.K Tapar

Many chemical entities and nutraceuticals are poor water soluble and show high lipophilicity. It’s difficult to formulate them into oral formulation because of its low aqueous solubility which ultimately affects bioavailability. To enhance the bioavailability of such drugs compounds, self microemulsifying drug delivery system is the reliable drug delivery system. In this system the drug is incorporated in the isotropic system and formulated as unit dosage form. Self microemulsifying drug delivery system is the novel emulsified system composed of anhydrous isotropic mixture of oils, surfactant, and co solvent and sometimes co surfactant. Drug is directly dispersed into the entire gastro intestinal tract with continuous peristaltic movement and drug is available in the solution form of microemulsion, absorbed through lymphatic system and bypasses the dissolution step. Hence they increase the patient compliance. The excipients are selected on basis of construction of ternary phase diagram. Self micro-emulsifying drug delivery system is very useful for drug in which drug dissolution is rate limiting step. This review describes the novel approaches and evaluation parameters of the self microemulsifying drug delivery system towards different classic drugs, proteins-peptides, and nutraceuticals in various oral microemulsion compositions and microstructures.


2019 ◽  
Vol 15 (6) ◽  
pp. 576-588 ◽  
Author(s):  
Beibei Yan ◽  
Yu Gu ◽  
Juan Zhao ◽  
Yangyang Liu ◽  
Lulu Wang ◽  
...  

: According to the drug discovery, approximately 40% of the new chemical entities show poor bioavailability due to their low aqueous solubility. In order to increase the solubility of the drugs, self-micro emulsifying drug delivery systems (SMEDDS) are considered as an ideal technology for enhancing the permeability of poorly soluble drugs in GI membranes. The SMEDDS are also generally used to enhance the oral bioavailability of the hydrophobic drugs. At present, most of the self-microemulsion drugs are liquid dosage forms, which could cause some disadvantages, such as the low bioavailability of the traditional liquid SMEDDS. Therefore, solid self-micro emulsifying drug delivery systems (S-SMEDDS) have emerged widely in recent years, which were prepared by solidifying a semi-solid or liquid self-emulsifying (SE) ingredient into a powder in order to improve stability, treatment and patient compliance. The article gives a comprehensive introduction of the study of SMEDDS which could effectively tackle the problem of the water-insoluble drug, especially the development of solidification technology of SMEDDS. Finally, the present challenges and the prospects in this field were also discussed.


Author(s):  
Sunitha M Reddy ◽  
Sravani Baskarla

This article describes current strategies to enhance aqueous solubility and dissolution rate of poor soluble drugs. Most drugs in the market are lipophilic with low or poor water solubility. There are various methods to enhance solubility: co-solvency, particle size reduction, salt formation and Self Nanoemulsifying drug delivery systems, SEDDS is a novel approach to enhance solubility, dissolution rate and bioavailability of drugs. The study involves formulation and evaluation of solid self-Nano emulsifying drug delivery system (S-SNEDDS) to enhance aqueous solubility and dissolution rate. Oral route is the most convenient route for non-invasive administration. S-SNEDDS has more advantages when compared to the liquid self-emulsifying drug delivery system. Excipients were selected depends upon the drug compatibility oils, surfactants and co surfactants were selected to formulate Liquid SNEDDS these formulated liquid self-nano emulsifying drug delivery system converted into solid by the help of porous carriers, Melted binder or with the help of drying process. Conversion process of liquid to solid involves various techniques; they are spray drying; freeze drying and fluid bed coating technique; extrusion, melting granulation technique. Liquid SNEDDS has a high ability to improve dissolution and solubility of drugs but it also has disadvantages like incompatibility, decreased drug loading, shorter shelf life, ease of manufacturing and ability to deliver peptides that are prone to enzymatic hydrolysis.  


2018 ◽  
Vol 55 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Zoran Popa ◽  
Laura Cristina Rusu ◽  
Razvan Susan ◽  
Iulia Pinzaru ◽  
Elena Ardelean ◽  
...  

The cloves are antiseptic, antiparasitic, antibacterial, antifungal, antiviral, anesthetic, analgesic, anti-inflammatory, tonic, carminative, anti-ulcer, antithrombotic, antioxidant and anti-cancerous. They contain eugenol, tannins and flavonoids that also help to strengthen the vein wall. This paper presents the obtaining and the characterization of a polyurethane drug delivery system which can be used for the transmembrane transport of eugenol in oral therapies. The products were analyzed by pH and solubility measurements, thermal decomposition and zetasizer tests and they were applied on mice skin to evaluate their harmfulness. The results suggest that were obtained neutral pH structures with low solubility and a good thermal stability, with sizes between 241 and 289 nm and no toxicity effect was found in the case of studied samples.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 271 ◽  
Author(s):  
Hyeongmin Kim ◽  
Chung-Lyol Lee ◽  
Seohyun Lee ◽  
Tae Jin Lee ◽  
Iqra Haleem ◽  
...  

In this study, we aimed to design a highly swellable and mechanically robust matrix tablet (SMT) as a gastroretentive drug-delivery system (GRDDS) capable of improving the dissolution behavior of β-lapachone with low aqueous solubility. For the preparation of SMTs, the cogrinding technique and freeze–thaw method were used to disperse β-lapachone in SMTs in an amorphous state and to enhance the swelling and mechanical properties of SMTs, respectively. As a result, the crystallinity of coground β-lapachone incorporated in the SMTs was found to be considerably decreased; thereby, the dissolution rates of the drug in a simulated gastric fluid could be substantially increased. The SMTs of β-lapachone also demonstrated significantly enhanced swelling and mechanical properties compared to those of a marketed product. The reason for this might be because the physically crosslinked polymeric networks with a porous structure that were formed in SMTs through the freeze–thaw method. In addition, β-lapachone was gradually released from the SMTs in 6 h. Therefore, SMTs of β-lapachone developed in this study could be used as GRDDS with appropriate swelling and mechanical properties for improving the dissolution behavior of hydrophobic drugs such as β-lapachone.


Diversity ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 162
Author(s):  
Michael R. Verhoeven ◽  
Wesley J. Glisson ◽  
Daniel J. Larkin

Potamogeton crispus (curlyleaf pondweed) and Myriophyllum spicatum (Eurasian watermilfoil) are widely thought to competitively displace native macrophytes in North America. However, their perceived competitive superiority has not been comprehensively evaluated. Coexistence theory suggests that invader displacement of native species through competitive exclusion is most likely where high niche overlap results in competition for limiting resources. Thus, evaluation of niche similarity can serve as a starting point for predicting the likelihood of invaders having direct competitive impacts on resident species. Across two environmental gradients structuring macrophyte communities—water depth and light availability—both P. crispus and M. spicatum are thought to occupy broad niches. For a third dimension, phenology, the annual growth cycle of M. spicatum is typical of other species, whereas the winter-ephemeral phenology of P. crispus may impart greater niche differentiation and thus lower risk of native species being competitively excluded. Using an unprecedented dataset comprising 3404 plant surveys from Minnesota collected using a common protocol, we modeled niches of 34 species using a probabilistic niche framework. Across each niche dimension, P. crispus had lower overlap with native species than did M. spicatum; this was driven in particular by its distinct phenology. These results suggest that patterns of dominance seen in P. crispus and M. spicatum have likely arisen through different mechanisms, and that direct competition with native species is less likely for P. crispus than M. spicatum. This research highlights the utility of fine-scale, abundance-based niche models for predicting invader impacts.


Planta Medica ◽  
2020 ◽  
Author(s):  
Patcharawalai Jaisamut ◽  
Subhaphorn Wanna ◽  
Surasak Limsuwan ◽  
Sasitorn Chusri ◽  
Kamonthip Wiwattanawongsa ◽  
...  

AbstractBoth quercetin and resveratrol are promising plant-derived compounds with various well-described biological activities; however, they are categorized as having low aqueous solubility and labile natural compounds. The purpose of the present study was to propose a drug delivery system to enhance the oral bioavailability of combined quercetin and resveratrol. The suitable self-microemulsifying formulation containing quercetin together with resveratrol comprised 100 mg Capryol 90, 700 mg Cremophor EL, 200 mg Labrasol, 20 mg quercetin, and 20 mg resveratrol, which gave a particle size of 16.91 ± 0.08 nm and was stable under both intermediate and accelerated storage conditions for 12 months. The percentages of release for quercetin and resveratrol in the self-microemulsifying formulation were 75.88 ± 1.44 and 86.32 ± 2.32%, respectively, at 30 min. In rats, an in vivo pharmacokinetics study revealed that the area under the curve of the self-microemulsifying formulation containing quercetin and resveratrol increased approximately ninefold for quercetin and threefold for resveratrol compared with the unformulated compounds. Moreover, the self-microemulsifying formulation containing quercetin and resveratrol slightly enhanced the in vitro antioxidant and cytotoxic effects on AGS, Caco-2, and HT-29 cells. These findings demonstrate that the self-microemulsifying formulation containing quercetin and resveratrol could successfully enhance the oral bioavailability of the combination of quercetin and resveratrol without interfering with their biological activities. These results provide valuable information for more in-depth research into the utilization of combined quercetin and resveratrol.


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