Microencapsulated probiotic Lactiplantibacillus plantarum and/or Pediococcus acidilactici strains ameliorate diarrhoea in piglets challenged with enterotoxigenic Escherichia coli

Lactiplantibacillus plantarum (strains 22F and 25F) and Pediococcus acidilactici (strain 72N) have displayed antibacterial activity in vitro, suggesting that they could be used to support intestinal health in pigs. The aim of this study was to determine if microencapsulated probiotics could reduce the severity of infection with enterotoxigenic Escherichia coli (ETEC) in weaned pigs. Sixty healthy neonatal piglets were cross-fostered and separated into five groups. Piglets to be given the microencapsulated probiotics received these orally on days 0, 3, 6, 9, and 12. Only piglets in groups 1 and 5 did not receive probiotics: those in groups 2 and 4 received the three microencapsulated probiotic strains (multi-strain probiotic), and piglets in group 3 received microencapsulated P. acidilactici strain 72N. After weaning, the pigs in groups 3-5 were challenged with 5 mL (at 10⁹ CFU/mL) of pathogenic ETEC strain L3.2 carrying the k88, staP, and stb virulence genes. The multi-strain probiotic enhanced the average daily gain (ADG) and feed conversion ratio (FCR) of weaned piglets after the ETEC challenge (group 4), whilst supplementing with the single-strain probiotic increased FCR (group 3). Piglets in groups 3 and 4 developed mild to moderate diarrhoea and fever. In the probiotic-fed piglets there was an increase in lactic acid bacteria count and a decrease in E. coli count in the faeces. By using real-time PCR, virulence genes were detected at lower levels in the faeces of pigs that had received the probiotic strains. Using the MILLIPLEX MAP assay, probiotic supplementation was shown to reduce pro-inflammatory cytokines (IL-1α, IL-6, IL-8, and TNFα), while group 4 had high levels of anti-inflammatory cytokine (IL-10). Challenged piglets receiving probiotics had milder intestinal lesions with better morphology, including greater villous heights and villous height per crypt depth ratios, than pigs just receiving ETEC. In conclusion, prophylactic administration of microencapsulated probiotic strains may improve outcomes in weaned pigs with colibacillosis.

Enhancement of large ring cyclodextrin production using pretreated starch by glycogen debranching enzyme from Corynebacterium glutamicum

Synthesis of large-ring cyclodextrins (LR-CDs) in any significant amount has been challenging. This study enhanced the LR-CDs production by Thermus filiformis amylomaltase (TfAM) enzyme by starch pretreatment using glycogen debranching enzyme from Corynebacterium glutamicum (CgGDE). CgGDE pretreated tapioca starch gave LR-CD conversion of 31.2 ± 2.2%, compared with LR-CDs produced from non-treated tapioca starch (16.0 ± 2.4%). CgGDE pretreatment enhanced amylose content by approximately 30%. Notably, a shorter incubation time of 1 h is sufficient for CgGDE starch pretreatment to produce high LR-CD yield, compared with 6 h required for the commercial isoamylase. High-Performance Anion Exchange Chromatography coupled with Pulsed Amperometric Detection (HPAEC-PAD) and Gel Permeable Chromatography (GPC) revealed that CgGDE is more efficient than the commercial isoamylase in debranching tapioca starch and gave lower molecular weight products. In addition, lower amount of by-products (linear oligosaccharides) were detected in cyclization reaction when using CgGDE-pretreated starch. In conclusion, CgGDE is a highly effective enzyme to promote LR-CD synthesis from starch with a shorter incubation time than the commercial isoamylase.

Targeted Gold Nanohybrids Functionalized with Folate-Hydrophobic-Quaternized Pullulan Delivering Camptothecin for Enhancing Hydrophobic Anticancer Drug Efficacy

This study presented a green, facile and efficient approach for a new combination of targeted gold nanohybrids functionalized with folate-hydrophobic-quaternized pullulan delivering hydrophobic camptothecin (CPT-GNHs@FHQ-PUL) to enhance the efficacy, selectivity, and safety of these systems. New formulations of spherical CPT-GNHs@FHQ-PUL obtained by bio-inspired strategy were fully characterized by TEM, EDS, DLS, zeta-potential, UV-vis, XRD, and ATR-FTIR analyses, showing a homogeneous particles size with an average size of approximately 10.97 ± 2.29 nm. CPT was successfully loaded on multifunctional GNHs@FHQ-PUL via intermolecular interactions. Moreover, pH-responsive CPT release from newly formulated-CPT-GNHs@FHQ-PUL exhibited a faster release rate under acidic conditions. The intelligent CPT-GNHs@FHQ-PUL (IC50 = 6.2 μM) displayed a 2.82-time higher cytotoxicity against human lung cancer cells (Chago-k1) than CPT alone (IC50 = 2.2 μM), while simultaneously exhibiting less toxicity toward normal human lung cells (Wi-38). These systems also showed specific uptake by folate receptor-mediated endocytosis, exhibited excellent anticancer activity, induced the death of cells by increasing apoptosis pathway (13.97%), and arrested the cell cycle at the G0-G1 phase. The results of this study showed that the delivery of CPT by smart GNHs@FHQ-PUL systems proved to be a promising strategy for increasing its chemotherapeutic effects.

The efficacy of three double-microencapsulation methods for preservation of probiotic bacteria

Lactic acid bacteria (LAB) are used as a probiotic alternative to antibiotics in livestock production. Microencapsulation technology is widely used for probiotic preservation. A variety of microencapsulation protocols have been proposed and compared based on chemicals and mechanical procedures. This study aimed to develop a double-encapsulated coating from alginate (1.5%) and chitosan (0.5%) by extrusion, emulsion, and spray drying methods using the LAB strains Lactobacillus plantarum strains 31F, 25F, 22F, Pediococcus pentosaceus 77F, and P. acidilactici 72N, and to monitor the basic probiotic properties of the encapsulated prototypes. The final products from each microencapsulation protocol were analysed for their appearance, probiotic properties and viable cell count. Using the spray drying method, particles smaller than 15 μm in diameter with a regular spherical shape were obtained, whereas the other methods produced larger (1.4–52 mm) and irregularly shaped microcapsules. After storage for 6 months at room temperature, the LAB viability of the spray-dried particles was the highest among the three methods. In all the LAB strains examined, the encapsulated LAB retained their probiotic properties in relation to acid-bile tolerance and antibacterial activity. This study highlights the efficacy of double-coating microencapsulation for preserving LAB properties and survival rate, and demonstrates its potential for probiotic application in livestock farms.

Collaboration Network and Trends of Global Coronavirus Disease Research: A Scientometric Analysis

As a global pandemic threatens health and livelihoods, finding effective treatments has become a vital issue that requires worldwide collaboration. This study examines research collaboration and network profiles through a case study of coronavirus diseases, including both the extinct severe acute respiratory syndrome coronavirus (SARS-CoV) and the emerging species (SARS-CoV-2). A scientometric process was designed to apply quantitative tools and a qualitative approach employing technological expertise to accomplish a three-level collaboration analysis. The text mining software, VantagePoint, was used to analyze research articles from the Web of Science database to identify the key national, organizational, and individual players in the coronavirus research field combined with indicators, namely, the breadth and depth of collaboration. The results show that China and the United States are at the center of coronavirus research networks at all three levels, including many endeavors involving single or joint entities. This study demonstrates how governments, public sectors, and private sectors, such as the pharmaceutical industry, can use scientometric analysis to gain insight into the holistic research trends and networks of players in this field, leading to the formulation of strategies to strengthen research and development programs. Furthermore, this approach can be utilized as a visualization and decision support tool for further policy planning, identification and execution of collaboration, and research exchange opportunities. This scientometric process should be directly applicable to other fields.

New organic/inorganic nanohybrids of targeted pullulan derivative/gold nanoparticles for effective drug delivery systems

This study aimed to develop new organic/inorganic nanohybrids of targeted pullulan derivative/gold nanoparticles (FA-PABA-Q188-PUL@AuNPs) to improve the selectivity and efficacy of drugs. The chemical structure of targeted pullulan derivative, folic acid-decorated para-aminobenzoic acid-quat188-pullulan (FA-PABA-Q188-PUL), was designed for reducing, stabilizing, capping, and functionalizing AuNPs. Here, the key factors, including pH, temperature, and FA-PABA-Q188-PUL concentrations, were systematically optimized to control the morphology, size, and functionalization of multifunctional FA-PABA-Q188-PUL@AuNPs. Spherical FA-PABA-Q188-PUL@AuNPs obtained by a green, simple, and bio-inspired strategy under the optimum conditions were thoroughly characterized and had an average size of 12.6 ± 1.5 nm. The anticancer drug DOX was successfully loaded on monodispersed FA-PABA-Q188-PUL@AuNPs and the system exhibited excellent intracellular uptake, specificity, and physicochemical properties. The pH-responsive DOX release from FA-PABA-Q188-PUL@AuNPs-DOX showed fast release (85% after 72 h) under acidic conditions. Furthermore, FA-PABA-Q188-PUL@AuNPs-DOX enhanced the anticancer activity of DOX toward Chago-k1 cancer cells up to 4.8-fold and showed less cytotoxicity toward normal cells than free DOX. The FA-PABA-Q188-PUL@AuNPs-DOX induced the death of cells by increasing late apoptotic cells (26.4%) and arresting the cell cycle at S-G2/M phases. These results showed that innovative FA-PABA-Q188-PUL@AuNPs should be considered as new candidate platforms for anticancer drug delivery systems.

Current Challenges and Opportunities in Treating Glioblastoma

Glioblastoma multiforme (GBM), the most common and aggressive primary brain tumor, has a high mortality rate despite extensive efforts to develop new treatments. GBM exhibits both intra- and intertumor heterogeneity, lending to resistance and eventual tumor recurrence. Large-scale genomic and proteomic analysis of GBM tumors has uncovered potential drug targets. Effective and “druggable” targets must be validated to embark on a robust medicinal chemistry campaign culminating in the discovery of clinical candidates. Here, we review recent developments in GBM drug discovery and delivery. To identify GBM drug targets, we performed extensive bioinformatics analysis using data from The Cancer Genome Atlas project. We discovered 20 genes, BOC, CLEC4GP1, ELOVL6, EREG, ESR2, FDCSP, FURIN, FUT8-AS1, GZMB, IRX3, LITAF, NDEL1, NKX3-1, PODNL1, PTPRN, QSOX1, SEMA4F, TH, VEGFC, and C20orf166AS1 that are overexpressed in a subpopulation of GBM patients and correlate with poor survival outcomes. Importantly, nine of these genes exhibit higher expression in GBM versus low-grade glioma and may be involved in disease progression. In this review, we discuss these proteins in the context of GBM disease progression. We also conducted computational multi-parameter optimization to assess the blood-brain barrier (BBB) permeability of small molecules in clinical trials for GBM treatment. Drug delivery in the context of GBM is particularly challenging because the BBB hinders small molecule transport. Therefore, we discuss novel drug delivery methods, including nanoparticles and prodrugs. Given the aggressive nature of GBM and the complexity of targeting the central nervous system, effective treatment options are a major unmet medical need. Identification and validation of biomarkers and drug targets associated with GBM disease progression present an exciting opportunity to improve treatment of this devastating disease.

Facile and green synthesis of pullulan derivative-stabilized Au nanoparticles as drug carriers for enhancing anticancer activity

In this work, we report for the first time AuNPs reduced/stabilized/capped with modified para-aminobenzoic acid-quat188-pullulan (PABA-QP) as excellent nanocarriers for delivery of doxorubicin to enhance the activity and safety of these systems. Spherical AuNPs@PABA-QP obtained by facile and green synthesis under optimum conditions were characterized by UV-VIS, TEM, EDS, SAED, XRD, ATR-FTIR and zeta-potential analyses and showed a narrow size distribution of 13.7 ± 1.9 nm. DOX was successfully loaded onto AuNPs@PABA-QP via intermolecular interactions with high drug loading. DOX-AuNPs@PABA-QP (IC₅₀ = 0.39μM) showed a 2.1-fold higher cytotoxicity against Chago cells than DOX alone (IC₅₀ = 0.82μM), while exhibiting less cytotoxicity against normal cells (Wi-38). Moreover, DOX-AuNPs@PABA-QP also demonstrated high intracellular uptake by endocytosis, arrested in S and G2-M phases of the cell cycle (total S/G2-M increased to approximately 18.0%), induced excellent cytotoxicity, and increased the fraction of late-apoptotic cells (18.6%). Consequently, it is suggested that the novel combination of DOX-AuNPs@PABA-QP has the potential to be developed for human cancer treatment.

Synthesis and biological evaluation of novel 2-oxo-1,2-dihydroquinoline-4-carboxamide derivatives for the treatment of esophageal squamous cell carcinoma

No new and effective treatments have been approved for the treatment of esophageal squamous cell carcinoma (ESCC) in the past decade. Cisplatin and 5-fluoruracil are the most commonly used drugs for this disease. In order to develop a new class of drugs effective in our ESCC phenotypic screens, we began a systematic approach to generate novel compounds based on the 2-oxo-1,2-dihydroquinoline-4-carboxamide fragment. Herein, we report on the synthesis and initial assessment of 55 new analogues in two ESCC cell lines. Some of the active analogues with IC₅₀ values around 10 μM were tested in three additional cell lines. Our structure-activity relationships revealed remarkable alterations in the anti proliferative activities upon modest chemical modifications and autophagy modulation is a suggested mechanism of action.

Novel organic/inorganic hybrid flower-like structure of selenium nanoparticles stabilized by pullulan derivatives

We proudly present the first organic/inorganic hybrid pullulan/SeNPs hybrid microflower material obtained using a simple and bio-inspired strategy. The chemical structures of pullulan, folic acid decorated cationic pullulan (FA-CP) were designed for stabilizing selenium nanoparticles (SeNPs). SeNPs stabilized by FA-CP hybrid microflowers were observed after the addition of a cysteine hydrochloride solution into the solution mixture of Na₂SeO₃ and FA-CP. We suggested that the concentrations of cysteine and FA-CP were the key factors for the formation of flower-like structure. In addition, the formation mechanism of the microflowers was tentatively identified as anisotropic hierarchical growth. The microflowers exhibited effective drug adsorption with the loading capacity of 142.2 mg g^-1 for doxorubicin which was three times higher than that for the doxorubicin-loaded spherical SeNPs and showed more potent activity against cancer cells while showing less toxicity against normal cells. These data demonstrated that the microflower-like FA-CP/SeNPs structure could be a candidate anticancer drug template in drug delivery systems.

Tautomeric-Dependent Lactam Cycloaddition with Nitrile Oxide: Facile Synthesis of 1,2,4-Oxadiazole[4,5-a]indolone Derivatives

A concise, metal-free, and gram-scale strategy to convert indoline-2,3-diones to 1,2,4-oxadiazole[4,5-a]indolones through an improved [3 + 2] cycloaddition of α-ketone-lactam with nitrile oxides has been developed. The lactim form of the resonance structure of isatin in protic solvents is the key active dipolarophile that shows chemo- and regioselectivity under experimental and theoretical conditions. This strategy conveniently enabled the assembly of several 1,2,4-oxadiazole[4,5-a]indolines with a broad range of functional groups. Compounds 3a and 4b exhibit cytotoxicity in the NCI/ADR-RES, SKOV3, and OVCAR8 cell lines.

Highly efficient and facile fabrication of monodispersed Au nanoparticles using pullulan and their application as anticancer drug carriers

This work presented a simple, rapid, green and efficient approach to the synthesis of gold nanoparticles using pullulan as a reducing/stabilizing/capping agent for drug delivery systems to increase the safety and efficacy of these systems. Monodispersed AuNPs@pullulan with prolonged stability were fully characterized by UV-VIS, FTIR, TEM, EDX, TGA and zeta potential analyses. A mechanism of AuNPs formation was proposed in which pullulan created reducing species for the reduction of Au³⁺ to AuNPs (Au⁰) that resulted in the formation of spherical AuNPs@pullulan with an average size of approximately 11±5nm, while the hydroxyl groups of pullulan were oxidized to carboxylate compounds. Novel cassiarin A chloride derivatives (3d and 3i) as candidate anticancer drugs were successfully loaded onto AuNPs@pullulan through electrostatic interactions. AuNPs@pullulan-3d (IC₅₀=6.0±0.1μM) and AuNPs@pullulan-3i (5.2±0.1μM) exhibited a 10.2-fold and 7.1-fold higher cytotoxicity against KATO-III cells than free compounds 3d (60.9±0.6μM), 3i (37.1±0.2μM) and cisplatin (64.5±0.9μM), respectively. AuNPs@pullulan exhibited high cellular uptake, biocompatibility and non-cytotoxicity to normal cells. Therefore, AuNPs@pullulan-3d or AuNPs@pullulan-3i have the potential to be developed for treatment of gastric cancer.

Nanogold-Gallate Chitosan-Targeted Pulmonary Delivery for Treatment of Lung Cancer

Lung cancer is one of the most of cancer type founds and a leading cause of death worldwide. Through the development of new candidate compound (3,4,5-tribenzyloxybenzoic acid (GAOBn)) and a drug delivery system of our design of quaternized chitosan-gallic acid-folic acid stabilized gold nanoparticles (Au@QCS-GA-FA) as the targeted nanocarrier for treatment of lung cancer, we have found that GAOBn not only showed high cytotoxicity against lung cancer cells (CHAGO) with more than tenfold than cisplatin, but also showed low toxicity against normal cells (CRL-1947). The combination Au@QCS-GA-FA/GAOBn showed highly efficient cellular uptake and localization of gold nanoparticles via the active targeting of cancer cells. This established the potential of Au@QCS-GA-FA as a nanocarrier for anticancer agent-targeted delivery for treatment of lung cancer.

Nanogold-Gallate Chitosan-Targeted Pulmonary Delivery for Treatment of Lung Cancer

Lung cancer is one of the most of cancer type founds and a leading cause of death worldwide. Through the development of new candidate compound (3,4,5-tribenzyloxybenzoic acid (GAOBn)) and a drug delivery system of our design of quaternized chitosan-gallic acid-folic acid stabilized gold nanoparticles (Au@QCS-GA-FA) as the targeted nanocarrier for treatment of lung cancer, we have found that GAOBn not only showed high cytotoxicity against lung cancer cells (CHAGO) with more than tenfold than cisplatin, but also showed low toxicity against normal cells (CRL-1947). The combination Au@QCS-GA-FA/GAOBn showed highly efficient cellular uptake and localization of gold nanoparticles via the active targeting of cancer cells. This established the potential of Au@QCS-GA-FA as a nanocarrier for anticancer agent-targeted delivery for treatment of lung cancer.

Design of peptides as inhibitors of human papillomavirus 16 transcriptional regulator E1-E2

Human papillomavirus 16 (HPV 16) is a DNA virus that is capable of infecting humans and causing cervical cancer. HPV16 E2 plays an important role in viral gene regulation. This work aims to predict the binding conformations and interactions between the dodecapeptides and HPV16 E2 as well as to design novel peptide inhibitors that are capable of binding to HPV16 E2 and disrupt the transcriptional regulator E1-E2 complex formation, using computational protein design techniques. Based on previously reported peptide4 (TWFWPYPYPHLP), novel peptide inhibitors were designed and five peptides that showed lower binding energy to HPV16 E2 than that of peptide4, were selected for in vitro experiments. Enzyme-linked immunosorbent (ELISA) assay showed that Y6R, W4H_Y6R, and W4H peptides bound to HPV16 E2 with higher affinity than peptide4 did. Moreover, Y6R, W4H_Y6R, and W4H peptides more effectively inhibited E1-E2 complex formation than peptide4. This work revealed important interactions between the peptides and E1-E2 complex, suggesting a strategy for development of more potent peptide inhibitors.

Design, synthesis, fabrication and in vitro evalution of mucoadhesive 5-amino-2-mercaptobenzimidazole chitosan as low water soluble drug carriers

Mucoadhesive thiolated chitosan suitable as a carrier for low water soluble drugs was designed and synthesized by conjugating 5-amino-2-mercaptobenzimidazole (MBI) using methylacrylate (MA) as the linking agent. A 14.4% degree of substitution of MA, as determined by (1)H NMR analysis, and 11.86±0.01μmol thiol groups/g of polymer, as determined by Ellman's method, was obtained. The MBI-MA-chitosan had an 11-fold stronger mucoadhesive property compared to unmodified chitosan at pH 1.2, as determined by the periodic acid: Schiff colorimetric method. Chitosan, MA-chitosan and MBI-MA-chitosan were fabricated as well-formed microspheres using electrospray ionization, including an entrapment efficiency of simvastatin (SV) of over 80% for the MBI-MA-chitosan. The mucoadhesiveness of the SV-loaded MBI-MA-CS microspheres was still higher than that for SV-loaded chitosan at pH 1.2 and 6.4. The SV-loaded MBI-MA-CS microspheres revealed a reduced burst effect and an increased release rate (more than fivefold higher than pure SV) of SV over 12h.

Enhanced water-solubility and mucoadhesion of N,N,N-trimethyl-N-gluconate-N-homocysteine thiolactone chitosan

A water-soluble chitosan with improved mucoadhesion was prepared by modifying 19.4% of the amine groups of chitosan to trimethylammonium and conjugation of gluconolactone (GLU) and homocysteine thiolactone (HT) onto the remaining amine groups of the chitosan backbone. The derived trimethyl-gluconate-HT-chitosan (TM-GN-HT-chitosan) was confirmed by Fourier Transform Infrared spectroscopy, NMR and thermogravimetric analysis. The total thiol and disulfide group level on the TM-GN-HT-chitosan were 17.96 ± 0.03 and 7.36 ± 0.03 μmol/g, respectively. The water solubility of the TM-GN-HT-chitosan conjugate was 79.0 ± 0.15%, more than that of TM-chitosan and chitosan, with an enhanced solubility over a broad pH range ranging from 85.6 ± 10.4% to 58.5±1.1% maximal solubility at pH 2 to 11. Finally, TM-GN-HT-chitosan showed a nearly ∼9.5-, 5.0- and 5.6-fold higher mucoadhesiveness than chitosan at pH 1.2, 4.0 and 6.4, respectively, and was optimal at pH 4.0.

Self-assembly of mucoadhesive nanofibers

Here, we present an easy and stable one-step procedure to fabricate self-assembled nanofibers from modified chitosan.

Mucoadhesive 4-carboxybenzenesulfonamide-chitosan with antibacterial properties

The mucoadhesive property of chitosan, especially in an acidic (<pH 6.0) environment, was increased by conjugating an aromatic sulfonamide group at the C2-N position of chitosan. Four different feeding ratios of 4-carboxybenzensulfonamide (4-CBS) to chitosan in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride as a coupling agent were investigated. The 0.2:1 (w/w) ratio 4-CBS:chitosan revealed a 20-fold stronger mucoadhesion to mucin type II than the native chitosan in the simulated gastric fluid (SGF; pH 1.2), and a swelling ratio after 1 h in water, SGF and simulated intestinal fluid (pH 7.4) of about 2.9-, 3.0- and 3.4-fold higher than that of chitosan, respectively. In tissue culture, the 4-CBS-chitosan, like chitosan, were found to be non-cytotoxic to the Vero, KB, MCF-7 and NCI-H187 cell lines but showed potential antibacterial activity against Escherichia coli and Staphlyococcus aureus as model gram-negative and gram-positive bacteria, respectively.

Andirobin from X. moluccensis

The title compound (systematic name: methyl 2-{(1R,2R)-2-[(1aS,4S,4aS,8aS)-4-(furan-3-yl)-4a-methyl-8-methyl­ene-2-oxoocta­hydro­oxireno[2,3-d]isochromen-7-yl]-2,6,6-trimethyl-5-oxocyclo­hex-3-en-1-yl}acetate), C₂₇H₃₂O₇, was isolated from X. moluccensis seeds from Thailand. The conformations of the six-membered rings are distorted half-chair, chair and half-chair for the isolated cyclo­hexane, fused cyclo­hexane and lactone rings, respectively. In addition, the lactone ring bears in an equatorial orientation an essentially planar furan ring (r.m.s. deviation = 0.004 Å), which forms an angle of 63.87 (13)° with the mean plane defined by the ten atoms of the two fused six-membered rings (r.m.s. deviation = 0.213 Å). The absolute configuration was fixed on the basis of literature data.

Bis(acetato-κ(2)O,O')(4,4'-dimethyl-2,2'-bipyridine-κ(2)N,N')copper(II) monohydrate

In the title compound, [Cu(C₂H₃O₂)₂(C₁₂H₁₂N₂)₂]·H₂O, the Cu^II atom exhibits a distorted octa­hedral coordination geometry, defined by two N atoms from one 4,4′-dimethyl-2,2′-bipyridine ligand and four O atoms from two acetate ligands. In the crystal, O—H⋯O hydrogen bonds are observed between the coordinated carboxyl­ate O atoms and the solvent water mol­ecule.

9,10-Dioxoanthracene-1,4-diyl bis-(4-methyl-benzene-sulfonate)

The title mol­ecule, C₂₈H₂₀O₈S₂, has a T-shaped conformation. The central 9,10-anthraquinone moiety is bow-shaped with the two outer aromatic rings being inclined to one another by 13.99 (11)°. The benzenesulfonate rings are inclined to one another by 47.35 (12)°, and by 34.51 (11) and 17.88 (11)° to the bridging aromatic ring of the 9,10-anthraquinone moiety. In the crystal, C—H⋯O interactions link the mol­ecules into ribbons in [100].

Synthesis of rotenoid derivatives with cytotoxic and topoisomerase II inhibitory activities

6-Deoxyclitoriacetal (1) and a series of 11 further derivatives of it (2-12) were synthesized and evaluated for their cytotoxic and topoisomerase IIα inhibitory activities. Compounds bearing epoxide (2), morpholine (6) and benzylamine (10) moieties showed promising in vitro cytotoxic activities against four cancer cell lines, with IC(50) values ranging from 0.38 to 0.73 μM. These three compounds also strongly inhibited topoisomerase II activity at 68.3-93.5% and showed a moderately high DNA intercalating property.

Electrospray fabrication of doxorubicin-chitosan-tripolyphosphate nanoparticles for delivery of doxorubicin

This work focused on a new technique for the preparation of doxorubicin (DOX) loaded chitosan (CS) nanoparticles (DOX-CS) - formation by electrospray ionization in the presence of tripolyphosphate (TPP) as the stabilizer. The working distance, needle gauge, flow rate, stirring rate, electrospraying voltage and DOX to CS molar ratio were sequentially and individually optimized and found to be a 26 gauge needle, an applied voltage of 13 kV, a flow rate of 0.5 mL/h, a working distance of 8 cm and a stirring rate of 400 rpm. The incorporation of chemically unchanged DOX with the CS into the particles was ascertained by Fourier transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Under these optimized conditions, the DOX-CS particles were found to be nanoparticles of approximately 300-570 (dry particles) or 530-870 nm diameter (hydrated particles), with a PDI and SPAN polydispersity indices of 0.97-0.82 and 0.62-0.64, respectively, for initial DOX loading levels of 0.25-1%, as determined by SEM and particle size analyzer, respectively. Moreover, a high encapsulation efficiency (EE) of DOX into the nanoparticles was attained, ranging from 63.4 to 67.9% EE at 1 to 0.25% DOX loading. Finally, the in vitro DOX release behaviors of the DOX-CS particles revealed a prolonged release of DOX over at least seven hours.

Sustained release of amoxicillin from ethyl cellulose-coated amoxicillin/chitosan-cyclodextrin-based tablets

Sustained release mucoadhesive amoxicillin tablets with tolerance to acid degradation in the stomach were studied. The sustained-release tablets of amoxicillin were prepared from amoxicillin coated with ethyl cellulose (EC) and then formulated into tablets using chitosan (CS) or a mixture of CS and beta-cyclodextrin (CD) as the retard polymer. The effects of various (w/w) ratios of EC/amoxicillin, the particle sized of EC coated amoxicillin and the different (w/w) ratios of CS/CD for the retard polymer, on the amoxicillin release profile were investigated. The physicochemical properties of the EC coated amoxicillin particles and tablets were determined by scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The result showed that the release profiles of amoxicillin were greatly improved upon coating with EC, while the inclusion of CD to the CS retardant additionally prolonged the release of the drug slightly. Overall, a sustained release of amoxicillin was achieved using amoxicillin coated with EC at a (w/w) ratio of 1:1 and a particle size of 75-100 μm. Therefore, the tablet formulation of amoxicillin may be an advantageous alternative as an orally administered sustained-release formulation for the treatment of peptic ulcers.

7-Deacetyl-gedunin

The title compound [systematic name: (1S,3aS,4aR,4bS,5R,6aR,10aR,10bR,12aS)-1-(furan-3-yl)-5-hy­droxy-4b,7,7,10a,12a-penta­methyl-4b,5,6,6a,7,10a,10b,11,12,12a-deca­hydro­naphtho­[2,1-f]oxireno[2,3-d]isochromene-3,8(1H,3aH)-dione], C₂₆H₃₂O₆, which is a limonoid-type triterpene isolated from the seeds of X. moluccensis, crystallizes with three independent mol­ecules with very similar geometries in the asymmetric unit. In each mol­ecule, the four fused six-membered rings of the genudin core adopt distorted half-chair, chair, twist-boat and twisted half-chair conformations. In the crystal, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules into helical chains propagated in [100]. Weak non-classical C—H⋯O contacts further consolidate the crystal packing.

2-[(4-Methoxybenzyl)iminomethyl]phenol

In the title Schiff base compound, C₁₅H₁₅NO₂, prepared from 4-meth­oxy­benzyl­amine and salicyl­aldehyde, an intra­molecular O—H⋯N hydrogen bonds influences the mol­ecular conformation; the two aromatic rings form a dihedral angle of 73.5 (1)°. In the crystal, weak inter­molecular C—H⋯O inter­actions link the mol­ecules into chains propagating in [010].

2-[(4-Chlorobenzyl)iminomethyl]phenol

The title Schiff base compound, C₁₄H₁₂ClNO, was prepared from 4-chloro­benzyl­amine and salicyl­aldehyde. The mol­ecule is V-shaped: the dihedral angle between the aromatic rings is 67.51 (5)°. The rings are located on the opposite side of the C=N bond, giving an E configuration. An intra­molecular N—H⋯O hydrogen bond generates a S(6) ring. In the crystal structure, only weak non-classical C—H⋯O contacts are observed.

Chitosan/polyethylene glycol beads crosslinked with tripolyphosphate and glutaraldehyde for gastrointestinal drug delivery

This study reports on the preparation of chitosan (CS)/polyethylene glycol (PEG) hydrogel beads using sodium diclofenac (DFNa) as a model drug. Following the optimization of the polymer to drug ratio, the chitosan beads were modified by ionic crosslinking with sodium tripolyphosphate (TPP). The CS/PEG/DFNa beads obtained from a (w/w/w) ratio of 1/0.5/0.5 with crosslinking in 10% (w/v) TPP at pH 6.0 for 30 min yielded excellent DFNa encapsulation levels with over 90% loading efficiency. The dissolution profile of DFNa from CS/PEG/DFNa beads demonstrated that this formulation was able to maintain a prolonged drug release for approximately 8 h. Among the formulations tested, the CS/PEG/DFNa (1/0.5/1 (w/w/w)) beads crosslinked with a combination of TPP (10% (w/v) for 30 min) and glutaraldehyde (GD) (5% (w/v)) were able to provide minimal DFNa release in the gastric and duodenal simulated fluids (pH 1.2 and 6.8, respectively) allowing for a principally gradual drug release over 24 h in the intestinal (jejunum and ileum) simulated fluid (pH 7.4). Thus, overall the CS/PEG beads crosslinked with TPP and GD look to be a promising and novel alternative gastrointestinal drug release system.

Salicyl-aldehyde-4-(dimethyl-amino)-pyridine (1/1)

In the title compound, C₇H₁₀N₂·C₇H₆O₂, the components are linked by an O—H⋯N hydrogen bond. The mean planes of two mol­ecules form a dihedral angle of 78.68 (5)°. The crystal packing exhibits weak non-classical C—H⋯O contacts.

Xylorumphiins A-D, mexicanolide limonoids from the seed kernels of Xylocarpus rumphii

Four new mexicanolide limonoids, named xylorumphiins A-D (1-4), were isolated from the seed kernels of Xylocarpus rumphii, together with three known limonoids. Their structures and configurations were established on the basis of spectroscopic data.