Phytosomal encapsulation of a panax ginseng root extract for increasing its efficacy and safety

Phytosomes are complexes created when an herbal substance is combined with phosphatidylcholine. The new molecule is both water-soluble and fat-soluble, for greater bioavailability and absorption. Panax ginseng root extract is used as a tonic agent or an adaptogen that helps to improve overall health. Several pharmacological effects of P. ginseng has been investigated e.g. improvement of physical and mental performance, immune stimulation, liver protection and regulating glycaemia level. The main active components of P.ginseng are ginsenosides saponins. Ginsenosides Phytosomes were prepared using an aprotic solvent which is methylene chloride. Two types of ginsenosides phytosomes were prepared from L-alpha- phosphatidylcholine obtained from either egg yolk or soybean. Amount of complexed ginsenosides was estimated directly in the complex [phytosomes] using UV-visible recording spectrophotometer. The ratio of complexation between ginsenosides and lipids was 1:3 w/w. Dissolution rate profiles of the two types of phytosomes are nearly the same and they showed more sustained release of ginsenosides compared to the root extract; that can be explained by increased lipophilicity of ginsenosides by lipid complexation; denoting that the biological effect of ginsenosides phytosomes is expected to be maintained for longer time than that for the root extract. Characterization of phytosomes was carried out using Proton Nuclear Magnetic Resonance [[1]HNMR], Carbon Thirteen Nuclear Magnetic Resonance [[13]CNMR], Fourier Transform Infrared spectroscopy [FT-IR] and Differential Scanning Calorimetry [DSC]. All these characterization techniques have provided an evidence of complex formation. Ginsenosides phytosomes prepared using soybean L-alpha- phosphatidylcholine were biologically evaluated for enhancing the immunity against S.mansoni cercariae. Infected mice were divided at random into three groups; one as a control, the other two groups were administered the free drug [P.ginseng root extract] and the complexed drug [ginsenosides phytosomes] orally. Immunological response for the three groups was assessed by Enzyme Linked Immunosorbent Assay [ELISA] and worm and ova count in both liver and intestine. The results proved the promoted biological efficacy for the group administered phytosomes; due to increased lipophilicity of ginsenosides attained by complexation with phospholipids

Praziquantel-polyethylene glycol 4000 solid dispersions enhancing drug dissolution rate and schistosomicidal activity

Praziquantel [PZQ] solid dispersions [SDs] with polyethylene glycol 4000 [PEG 4000] were prepared by the co-evaporation method using absolute ethanol. Different drug: polymer ratios viz., 90:10 [10% SD], 80:20 [20% SD], 70:30 [30% SD] and 20% physical mixture [PM] were used and the prepared SDs as well as the drug were evaluated through differential scanning calorimetry [DSC], X-ray diffraction [XRD], dissolution, ex-vivo and in-vivo studies. The results revealed that the improvement achieved in physical properties of the drug, via SD, affected its dissolution rate in 0.1N HCI, pH: 1.2 where the 20% SD showed maximum enhancement of dissolution rate compared to all other systems. In addition, ex-vivo and in-vivo studies revealed higher efficacy of the 20% SD system in reducing worm burden, ova count and granuloma count and diameter, in mice infected with S. mansoni, compared to free PZQ. Finally we conclude that the 20% SD of PZQ with PEG 4000, bearing 80% PZQ, instead of 100% in the free state, could be used as an oral alternative to free PZQ, yielding better absorption and schistosomicidal activity against S. mansoni, with reduced side effects

Three months chemoprophylaxis of shistosomiasis using liposome encapsulated oxamniquine

Oxamniquine liposomes of the molar ratio 7:6, neutral and negatively charged, were prepared by the vortex dispersion method. Entrapped oxamniquine was estimated by HPLC analysis. Percentage drug encapsulated was found to range from 12.4% [neutral liposomes] to 20% [negative liposomes]. Drug-free and oxamniquine liposomes were characterized by particle-size analysis and Differential-scanning-calorimetry. Liver disposition of oxamniquine liposomes in mice, three-months post [s.c.] injection was investigated. Results reveal that oxamniquine liposomes are better liver-targeted than the free drug. Chemoprophylaxis of oxamniquine liposomes against S. mansoni in mice, was assessed for three months where drug liposomes displayed highly significant protection of 44%, unlike the free drug preparation; 1.3%. Stability study of oxamniquine liposomes was conducted on negative and neutral liposomes at -10, 4°, and 25°. Neutral liposomes displayed better sustained release of the drug over the negative ones. Storage at -10° provides more stable drug- liposomes. Sterilization of negatively charged oxamniquine liposomes was conducted employing four doses of gamma radiation of 10, 15, 20 and 25 KGy. Results revealed that 25 KGy is the optimum sterilizing dose, in addition to inferring high stability to the product

Optimising liposome-encapsulated praziquantel formulations for treating and overcoming resistant isolates of schistosoma mansoni

Praziquantel [pzq.] liposomes of [DPPC: Cholesterol] molar ratio 7:2, neutral [N] and negatively [-ve] charged, were prepared by the vortex dispersion method yielding multilamellar vesicles [MLV]. Some MLV were sonicated yielding unilamellar vesicles [ULV]. Entrapped pzq. was measured using UV spectrophotometric analysis at 265 nm. [N] UL and ML liposomes exhibited higher percentage entrapment over the [-ve] liposomes. Swelling at 52° for 24 hours, led to increased percentage entrapment of UL pzq. liposomes. Transmission electron micrographing was employed to characterize ML liposomes. [N] pzq. liposomes, of higher percentage entrapment, were used in curative and prophylactic experiments against susceptible [S] and resistant [R] isolates of S. mansoni, in mice. Pzq. liposomes were injected subcutaneously [s.c.] to effect efficient targeting to the site of infection viz., the liver. The effect of pzq. liposomes, in half dose, was compared to the same dose of free pzq, administered orally and as s.c. injection, in addition to full oral free pzq. [1000 mg/kg]. The curative experiment showed best efficacy for full oral free pzq. On the other hand, [N] pzq. ML liposomes imparted the highest 7-days chemoprophylactic effect against both [S] and [R] isolates of S. mansoni, emphasizing the significant success of such a pharmaceutical formulation in conquering the [R] S. mansoni isolate [EE2] responsible for evolving resistance to pzq. curative effect, in the Egyptian population