Isolation, Antimicrobial Effect and Metabolite Analysis of Bacillus amyloliquefaciens ZJLMBA1908 against Citrus Canker Caused by Xanthomonas citri subsp. citri.

Citrus canker caused by Xanthomonas citri subsp. citri is a devastating bacterial disease with severe implications for the citrus industry. Microorganisms possessing biocontrol capabilities against X. citri subsp. citri offer a highly promising strategy for healthy citrus management. In the present study, a broad-spectrum antagonist strain ZJLMBA1908 with potent antibacterial activity against X. citri subsp. citri was isolated from symptomatic lemon leaves, and identified as Bacillus amyloliquefaciens. Cell-free supernatant (CFS) of strain ZJLMBA1908 also exhibited remarkable antimicrobial activity, especially suppressing the growth of X. citri subsp. citri and Nigrospora oryzae, with inhibition rates of 27.71% and 63.75%, respectively. The antibacterial crude extract (CE) derived from the CFS displayed effective activity against X. citri subsp. citri. A preventive treatment using the CE significantly reduced the severity and incidence of citrus canker in a highly susceptible citrus host. Additionally, the CE maintained activity in the presence of protease and under a wide range of temperature and pH treatments. Applying high-performance liquid chromatography (HPLC) to separate and purify the CE resulted in the discovery of one highly potent anti-X. citri subsp. citri subfraction, namely CE3, which could completely inhibit the growth of X. citri subsp. citri. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analysis revealed that CE3 mainly consisted of palmitic acid, surfactin C15, phytosphingosine and dihydrosphingosine. Taken together, the results contribute to the possible biocontrol mechanisms of B. amyloliquefaciens ZJLMBA1908, as well as providing a promising new candidate strain as a biological control agent for controlling citrus canker.

Protective effects of psoralen polymer lipid nanoparticles on doxorubicin - induced myocardial toxicity

Abstract Doxorubicin (DOX) induced myocardial toxicity may limit its therapeutic use in clinic. Psoralen (PSO), a major active tricyclic furocoumarin extracted from Psoralea corylifolia, is widely used as an antineoplastic agent in treatment of leukemia and other cancers. This study is aim to find the protective effect of psoralen polymer lipid nanoparticles (PSO-PLN) on doxorubicin-induced myocardial toxicity in mice. The model of myocardial toxicity induced by DOX was established. The experiment was divided into 6 groups: normal saline group, DOX + Sulfotanshinone Sodium, DOX + PSO-PLN (3 mg/kg), DOX + PSO-PLN (6 mg/kg), DOX + PSO-PLN (9 mg/ kg), DOX group. DOX alone treated mice lead to a significant decrease in the body weight, heart weight, and increase in the serum levels of lactate dehydrogenase (LDH), creatine kinase (CK) and malondialdehyde (MDA) markers of cardiotoxicity. However, DOX reduced glutathione (GSH) content and activities of antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GPX), were recovered by PSO-PLN. And PSO-PLN also decreased markers of cardiotoxicity in the serum. Western blotting data showed that the protective effects of PSO-PLN might be mediated via regulation of protein kinase A (PKA) and p38. Our study suggest that PSO-PLN possesses antioxidant activities, inactivating PKA and p38 effect, which in turn protect the heart from the DOX-induced cardiotoxicity.

Design and development of spirulina polysaccharide-loaded nanoemulsions with improved the antitumor effects of paclitaxel.

Aims: In this study, we prepared spirulina polysaccharides into spirulina polysaccharide-loaded nanoemulsions (SPS-NEs), and determined the antitumor effect of SPS-NEs, when combined with paclitaxel (PTX).Methods: SPS-NEs were prepared by a phase transformation method. The Characterisation and stability of SPS-NEs was measured. The antitumor effect of SPS-NEs combined with PTX was determined by S180 cells or RAW 264.7 macrophages and S180 tumour-bearing mice.Results: SPS-NEs were spherical and stable, the particle size of SPS-NEs was 84.6 ± 3.31 nm, PDI = 0.235 ± 0.02. PTX + SPS-NEs exhibited a much greater toxicity against RAW 264.7 cells than PTX. PTX + SPS-NEs increased the release of NO, IL-6 and TNF-α, and the expression of p-p65 NF-κB, p-I-κB, TLR4. In addition, PTX + SPS-NEs significantly inhibited tumour growth by 72.82% and increased the secretion of serum IL-2, TNF-α and IFN-γ.Conclusions: SPS-NEs can regulate immunity through TLR4/NF-κB signalling pathways, which enhances the anti-tumour effect of PTX.

Nanotargeted agents: an emerging therapeutic strategy for breast cancer.

Breast cancer is the most common female cancer worldwide and represents 12% of all cancer cases. Improvements in survival rates are largely attributed to improved screening and diagnosis. Conventional chemotherapy remains an important treatment option but it is beset with poor cell selectivity, serious side effects and resistance. Nanoparticle drug delivery systems bring promising opportunities to breast cancer treatment. They may improve chemotherapy by targeting drugs to tumors, generating high drug concentrations at tumors providing slow release of the drug, increased drug stability and concomitant reductions in side effects. The nanotechnology-based drug delivery approaches and the current research and application status of nano-targeted agents for breast cancer are discussed in this review to provide a basis for further study on targeted drug delivery systems.

A review of pharmacological and clinical studies on the application of Shenling Baizhu San in treatment of Ulcerative colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: The prescription of Shenling Baizhu San (SLBZS) was derived from the Song Dynasty "Taiping Huimin Heji Ju Fang", which was a representative prescription for treating spleen asthenic diarrhea. The prescription comprised of 10 herbs for treating weak spleen and stomach. It describes symptoms like eating less, loose stools, cough, shortness of breath and tired limbs. SLBZS has been reported to be capable of eliminating discomfort when it is administered for treating irritable bowel syndrome and diarrhea. This traditional Chinese medicine (TCM) formula has been widely used for improving gastrointestinal dysfunction and modifying the immune response to inflammation. AIM OF THE STUDY: This review is aimed to provide the up-to-date information on the pharmacology and clinical research of SLBZS in the treatment of ulcerative colitis (UC), and to discuss the research findings and possible deficiencies, hoping to better guide the clinical application and scientific research of SLBZS in the treatment of UC. MATERIALS AND METHODS: Relevant studies from 2004 to 2018 on SLBZS in the treatment of UC mechanism and curative effect were collected from ancient books, pharmacopoeia, reports, thesis via library and Digital databases (PubMed, CNKI, Google Scholar, Web of Science, SciFinder, Springer, Elsevier, etc). RESULTS: SLBZS could regulate inflammatory factors and intestinal flora, and ERK/p38 MAPK signaling pathway may be one of its targets. In addition, clinical research results show that SLBZS has a good therapeutic effect on UC, and the adverse reactions are small. CONCLUSION: Although SLBZS has achieved some success in the treatment of UC, there are still some scientific gaps. There is a lack of uniform standards for constructing UC animal models, and some methods of modeling through environmental and dietary interventions are not reproducible, and there is a lack of uniform dosing regimen standards. SLBZS doses follow the tradition and lack toxicological validation. Therefore, more specific toxicological research models are essential. The clinical application of SLBZS requires reassessment and standardization. Although all clinical research reports randomly assigned patients to different groups, most did not describe a detailed method of randomization and no description of the analysis data. In addition, extensive in vitro studies and further in-depth molecular studies are essential for the determination of mechanisms that have been performed in all in vivo experiments on animal models and patients.

Psoralen-loaded lipid-polymer hybrid nanoparticles enhance doxorubicin efficacy in multidrug-resistant HepG2 cells.

BACKGROUND: Psoralen (PSO), a major active component of Psoralea corylifolia, has been shown to overcome multidrug resistance in cancer. A drug carrier comprising a lipid-monolayer shell and a biodegradable polymer core for sustained delivery and improved efficacy of drug have exhibited great potential in efficient treatment of cancers. METHODS: The PSO-loaded lipid polymer hybrid nanoparticles were prepared and characterized. In vitro cytotoxicity assay, cellular uptake, cell cycle analysis, detection of ROS level and mitochondrial membrane potential (ΔΨm) and western blot were performed. RESULTS: The P-LPNs enhanced the cytotoxicity of doxorubicin (DOX) 17-fold compared to free DOX in multidrug resistant HepG2/ADR cells. Moreover, P-LPNs displayed pro-apoptotic activity, increased levels of ROS and depolarization of ΔΨm. In addition, there were no signifi-cant effects on cellular uptake of DOX, cell cycle arrest, or the expression of P-glycoprotein. Mechanistic studies suggested that P-LPNs enhanced DOX cytotoxicity by increased release of cytochrome c and enhanced caspase3 cleavage, causing apoptosis in HepG2/ADR cells. CONCLUSION: The lipid-polymer hybrid nanoparticles can be considered a powerful and promising drug delivery system for effective cancer chemotherapy.

Polymer-lipid hybrid nanoparticles: A novel drug delivery system for enhancing the activity of Psoralen against breast cancer.

A polymer-lipid hybrid nanocarrier was developed to encapsulate psoralen (PSO) to improve its water solubility and bioavailability. The effects of PSO-loaded polymer-lipid hybrid nanoparticles (PSO-PLNs) on breast cancer MCF-7 cells were investigated. PSO-PLNs were prepared through a nanoprecipitation method and were optimized by a central composite design-response surface methodology using particle size and entrapment efficiency as indices. Dynamic light scattering and transmission electron microscopy analysis confirmed the physicochemical characterizations of PSO-PLNs, which had an average size of 93.44 ±â€¯2.39 nm and a zeta potential of -27.63 ±â€¯0.31 mV. In vitro drug release of PSO-PLNs was evaluated using dialysis and showed a delayed release compared with free PSO. The in vivo anticancer efficiency of PSO-PLNs was appreciated using a MCF-7 breast tumor model. Administration of PSO-PLNs showed similar antitumor efficacy but lower toxicity compared with doxorubicin. Our designed nanocarriers successfully optimized the pharmacokinetics of PSO via improved systemic delivery.

Extraction of Polysaccharide from Spirulina and Evaluation of Its Activities.

BACKGROUND: Polysaccharide of Spirulina platensis (PSP) is a kind of water-soluble polysaccharide extracted from Spirulina platensis. It has been proved to have antitumor, antioxidation, antiaging, and antivirus properties. And it has a promising prospect for wide application. OBJECTIVE: This study aims to identify an extraction process for high-purity polysaccharide in Spirulina (PSP) through a series of optimization methods and then evaluates its initial antiaging activities. METHODS: Four kinds of extraction methods-hot-water extraction, alkali extraction, ultrasonic-assisted extraction, and freeze-thaw extraction-were compared to find the optimal one, which was further optimized by response surface methodology. PSP was obtained after the crude PSP was deproteinized and depigmented. The antiaging effects of PSP were preliminarily evaluated through in vitro cell experiments. RESULTS: The alkali extraction method was determined as the optimal method, with the optimized extraction process consisting of a solid-liquid ratio of 1 : 50, a pH value of 10.25, a temperature of 89.24°C, and a time of 9.99 h. The final PSP contained 71.65% of polysaccharide and 8.54% of protein. At a concentration of 50 µg/mL, PSP exerted a significant promoting effect on the proliferation and traumatic fusion of human immortalized epidermal cells HaCaT. CONCLUSION: An extraction method for high-purity PSP with a high extraction rate was established, and in vitro results suggest antioxidation and antiaging activities.

Preparation and evaluation of spirulina polysaccharide nanoemulsions.

The aim of the present study was to prepare spirulina polysaccharide (PSP) into an oral nanoemulsion (NE) with the aim of improving its oral bioavailability and prolonging its sustained release effect. The PSP­NE was prepared through a phase transformation method, and its formulation components were screened through the use of a pseudo­ternary phase diagram. The optimal formulation of PSP­NE was determined to be: 11.9% Span 80, 6.0% Tween-80, 9.0% ethanol, 62.8% soybean oil, and 10.3% PSP aqueous solution. The prepared PSP­NE was clear and transparent, had a uniform color and spherical morphology, exhibited stability and no adhesion. The average particle size was 79.93±19 nm, the polydispersity index was 0.185±0.04 (n=3), and the entrapment rate was 62%. Small­animal imaging results showed that the prepared PSP­NE exhibited a sustained release and tissue effect in contrast to the PSP aqueous solution. The present study showed that the prepared PSP­NE not only exhibited a sustained release and tissue effect in contrast to the PSP aqueous solution, but also had superior performance in terms of antitumor and antioxidant effects.