Search

Curcumin, the main component of turmeric (Curcuma longa) is known to display an interesting bioactivity profile, including pronounced anticancer properties. However, its low bioavailability, metabolic instability and nonspecific activity are concerns that have to be addressed before curcuminoids can be considered for therapeutic applications. Within that framework, intensive research has been carried out in the last decades to develop new curcumin derivatives, generally centered on standard modifications of the sp(2) curcumin framework, with the aim to augment its bioavailability while maintaining or improving its anticancer properties. To find potential hit molecules by moving away from the classical flat curcumin framework, we investigated an unexplored modification to produce novel, out-of-plane 1,4-thiazepane-based curcuminoids and assessed the impact of this modification on the biological activity. In this way, 21 new, structurally diverse thiazepane scaffolds (4-aryl-1-(7-aryl-1,4-thiazepan-5-ylidene)but-3-en-2-ones) were synthesized, as well as some biologically interesting unexpected reaction products (such as 5-aryl-6-arylmethylene-3-ethoxycyclohex-2-en-1-ones and 4-acetyl-5-aryl-2-(3-arylacryloyl)-3-methylcyclohex-2-en-1-ones). All these analogues were subsequently tested on their antioxidant capacity, their cytotoxicity properties and their ROS (reactive oxygen species) production. Many compounds demonstrated interesting activities, with ten curcuminoids, whereof eight 1,4-thiazepane-based, showing better antiproliferative properties compared to their mother compounds, as well as an increased ROS production. This unprecedented 3D curcumin modification has thus delivered promising new hit compounds with good activity profiles eligible for further exploration.

Type 1 resistant starch (RS1) has recently received tremendous attention from various research areas such as food science, nutrition, microbiology, and pharmaceutical technology due to its ability to resist digestion in the upper gastrointestinal tract. The protective barriers of RS1 play a vital role in the reduction of starch hydrolysis, glucose absorption, and the glycemic response that has the potential to limit the prevalence of some diseases by delaying the reaction of the digestive enzymes and extending glucose release. This work aims to provide a comprehensive review of RS1 mechanisms in controlling starch digestion and a summary of its industrial applications in relation to health benefits. Despite extensive research in this area, the review exposed some unrevealed aspects of RS1 that would require further study.

Acidovorax citrulli, a seedborne bacterium and quarantine pest, causes the devastating bacterial fruit blotch disease in cucurbit plants. Immunological assays such as ELISA are widely used in routine field inspections for this bacterium. However, to the best of our knowledge, none of the currently available monoclonal antibodies (MAbs) can detect all common A. citrulli strains. We therefore aimed to produce a panel of MAbs and to develop an ELISA-based method capable of detecting all A. citrulli strains. We used a high-throughput bead array technique to screen and characterize A. citrulli-specific MAbs produced from hybridoma clones. The hybridoma library was simultaneously screened against five A. citrulli strains (PSA, KK9, SQA, SQB and P) and the closely related bacterium, Delftia acidovorans. Three MAbs exhibiting different binding patterns to A. citrulli were used to develop an ELISA-based method called "double antibody pairs sandwich ELISA" (DAPS-ELISA). DAPS-ELISA employing mixtures of MAbs was able to specifically detect all 16 A. citrulli strains tested without cross-reactivity with other bacteria. By contrast, our previously developed MAb capture-sandwich ELISA (MC-sELISA) and a commercial test kit detected only 15 and 14 of 16 strains, respectively. The sensitivity of the DAPS-ELISA ranged from 5×105 to 1×106 CFU/mL, while those of the MC-sELISA and the commercial test kit ranged from 5×104 to 1×107 CFU/mL and 5×104 to 5×105 CFU/mL, respectively. DAPS-ELISA thus represents an alternative method enabling rapid, accurate, and inexpensive detection of all A. citrulli strains. The method can be applied to seed testing prior to planting as well as to routine field inspections.

Curcumin, a natural compound extracted from the rhizomes of Curcuma Longa, is known to display pronounced anticancer activity but lacks good pharmacokinetic properties. In that respect, augmenting the water solubility by structural modification of the curcumin scaffold may result in improved bioavailability and pharmacokinetics. A possible scaffold modification, especially important for this study, concerns the imination of the labile β-diketone moiety in curcumin. Previous work revealed that novel N-alkyl β-enaminones showed a similar water solubility as compared to curcumin, accompanied by a stronger anti-proliferative activity. To extend this β-enaminone compound library, new analogues were prepared in this work using more polar amines (hydroxyalkylamines and methoxyalkylamines instead of alkylamines) with the main purpose to improve the water solubility without compromising the biological activity of the resulting curcuminoids. Compared to their respective parent compounds, i.e. curcumin and bisdemethoxycurcumin, the bisdemethoxycurcumin N-(hydroxy/methoxy)alkyl enaminone analogues showed better water solubility, antioxidant and anti-proliferative activities. In addition, the curcumin enaminones displayed activities comparable to or better than curcumin, and the water solubility was improved significantly. The constructed new analogues may thus be of interest for further exploration concerning their impact on oxidative stress related diseases such as cancer.

TiAl3–Ti Laminated composite has been fabricated by hot pressing of titanium–aluminium sandwich in order to improve impact toughness of TiAl3. Fabrication process has been reported and structure evolution, phase portion, hardness, impact toughness, and fractography of the composite are investigated using XRD, XPS, SEM, EDS, hardness test, and impact test. The results show formation of TiAl3 and production of TiAl3–Ti laminated composite after the sandwiches have been hot pressed at 600 and 650 °C for 24 h in low vacuum system. TiAl3–Ti thickness ratio attributed to phase portion and hardness of TiAl3–Ti interface region are shown to be promoted by fabrication temperature. Fractography and EDS results can allow the impact–fracture mechanism of composite to be proposed. The impact toughness of composite can be improved by using low fabrication temperature in order to reduce TiAl3–Ti thickness ratio.

Curcumin, a natural compound extracted from the rhizomes of Curcuma longa, displays pronounced anticancer properties but lacks good bioavailability and stability. In a previous study, we initiated structure modification of the curcumin scaffold by imination of the labile β‐diketone moiety to produce novel β‐enaminone derivatives. These compounds showed promising properties for elaborate follow‐up studies. In this work, we focused on another class of nitrogen‐containing curcuminoids with a similar objective: to address the bioavailability and stability issues and to improve the biological activity of curcumin. This paper thus reports on the synthesis of new pyridine‐, indole‐, and pyrrole‐based curcumin analogues (aza‐aromatic curcuminoids) and discusses their water solubility, antioxidant activity, and antiproliferative properties. In addition, multivariate statistics, including hierarchical clustering analysis and principal component analysis, were performed on a broad set of nitrogen‐containing curcuminoids. Compared to their respective mother structures, that is, curcumin and bisdemethoxycurcumin, all compounds, and especially the pyridin‐3‐yl β‐enaminone analogues, showed better water solubility profiles. Interestingly, the pyridine‐, indole‐, and pyrrole‐based curcumin derivatives demonstrated improved biological effects in terms of mitochondrial activity impairment and protein content, in addition to comparable or decreased antioxidant properties. Overall, the biologically active N‐alkyl β‐enaminone aza‐aromatic curcuminoids were shown to offer a desirable balance between good solubility and significant bioactivity.

This paper demonstrates the design, development and implementation of mobile learning in a museum setting. Learning can be more effective when it is contextualized and situated; base on this assumption we develop a database system to collect information of artifacts (trees) in a museum (an open area agriculture museum) and present to users or learners through mobile application. Information on the mobile application can be fetched by scanning QR code. Users can walk within the area and scan a QR code on a tree to get a specific information; therefore, user can get details of the particular tree including name, species and its application. User satisfaction survey was collected and they are satisfied with the functions and information of the application.

Curcuminoids are high-potential drugs targeting multiple components of vital signaling pathways without being toxic, and are therefore considered to be valuable lead structures in medicinal chemistry. Unfortunately, most curcuminoids poorly reach their site of action because of low bioavailability issues, (partly) associated with the labile β-diketo structure. In that respect, curcumin derivatives bearing a central β-enaminone fragment may have improved solubility and intestinal stability, and therefore may represent a new class of analogs with higher bioactivity. In that mindset, thirteen N-alkyl enaminones were efficiently synthesized via a novel approach, using montmorillonite K10 clay and microwave irradiation. These compounds were then characterized in terms of solubility and chemical anti-oxidant properties, and were applied in screening assays for cell toxicity, growth and oxidative stress using CHO-K1, EA.hy926, HT-29 and Caco-2 cell lines. Compared to native curcumin, many nitrogen derivatives showed a stronger antiproliferative effect, which was highly structure and cell type dependent. In addition, the correlation between cell viability and reactive oxygen species production was limited. Therefore, this set of novel curcumin derivatives may be useful to unravel other mechanisms of oxidative stress-related diseases, and eventually be used as more bioavailable and bioactive alternatives for native curcumin.

With the goal to improve the aqueous solubility of lamellarins, the lactone ring in their skeleton was replaced with a lactam moiety in azalamellarins. However, the reported synthetic route produced such derivatives in very low yields. Hence, this study focused on developing an efficient simplified total synthetic scheme that could furnish both azalamellarins and the parent lamellarins from the same pyrrole ester intermediates. Subsequent comparative profiling revealed that the introduced lactone-to-lactam replacement rendered these molecules less lipophilic, whereas their cancer cytotoxicity remained equipotent to that of the parent compounds. Interestingly, their inhibitory activity was significantly enhanced towards the multifaceted GSK-3β enzyme. Our results clearly demonstrate the therapeutic potential of this promising class of marine-derived natural products and justify their further development, especially into anticancer agents.

Internet is more prevalent today, especially on mobile phone. The internet can be used anywhere to make it easy to find the information at any time. At present, the number of tourists has increased, especially for travelers who like to travel in Thailand. The problems are that many of the tourist attractions, travel search, just a passport. The map is not enough for the journey of a group of tourists. It has solved the problem by using the convenience of the Internet to help in identifying the attractions in the vicinity. Paths where tourists want to go with a GIS such as restaurants, hotels, etc. By the Sea Island Resort National Park displays the results based on the needs of the tourists on the web internet.