[en] Turmeric (Curcuma longa), belongs to Zingiberaceae family. The rhizomes contain bioactive compounds of the curcuminoids group (natural phenols). They are used in food and pharmaceutical industry. The aim of this research was to acquire dried turmeric with high total curcumin content. In this study, optimum turmeric drying conditions and new extraction techniques were explored. Fresh turmeric samples were subjected to constant vs changing drying air temperatures and pre-treatment (blanching). Changing drying air temperature and use of non-blanched turmeric slices resulted in the highest concentration of curcumin. Ultrasonic extraction instead of soxhlet extraction improved the extraction efficiency and decreased extraction time. (Author)

[en] A small set of structurally different monocarbonyl curcuminoids was prepared and screened for cytotoxic activity. In particular, bis-3-methoxy-4-hydroxy- and bis-4-methoxyphenyl-substituted monocarbonyls were synthesized and transformed into the corresponding three-dimensional N-acetylpyrazoline derivatives. In addition, a non-symmetrical indole-based monocarbonyl curcumin was prepared as well. Preliminary cytotoxic evaluation revealed significant effects for 4-hydroxy (pyrazoline) monocarbonyl curcuminoids, whereas the non-phenolic variants displayed rather poor activity. Graphic abstract:

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[en] Highlights: • Curcumin identified as a direct binding partner of IL-2. • Binding between IL-2 and IL-2 receptor alpha is reduced by curcumin. • Curcumin counteracts the side effect of IL-2, vascular leak syndrome. Interleukin-2 (IL-2) is a crucial growth factor for both regulatory and effector T cells. Thus, IL-2 plays a critical role in the stimulation and suppression of immune responses. Recently, anti-IL-2 antibodies (Abs) have been shown to possess strong IL-2 modulatory activities by affecting the interaction between IL-2 and IL-2 receptors. In this study, we screened an herbal library to identify a compound that regulates IL-2, which resulted in the identification of curcumin as a direct binder and inhibitor of IL-2. Curcumin is a phytochemical with well-known anti-cancer properties. In this study, curcumin mimicked or altered the binding pattern of anti-IL-2 Abs against IL-2 and remarkably inhibited the interaction of recombinant IL-2 with the IL-2 receptor α, CD25. Interestingly, curcumin neutralized the biological activities of IL-2 both in vitro and in vivo. In this report, we elucidated the unsolved mechanism of the anti-cancer effect of curcumin by identifying IL-2 as a direct molecular target. Curcumin, as a small molecule IL-2 modulator, has the potential to be used to treat IL-2 related pathologic conditions.

[en] Amyloid fibrillary aggregates, which are gradually formed under predisposing conditions in the human body, are the main sign of conformational diseases such as type 2 diabetes, Alzheimer's disease and Parkinson's disease. How the aggregates are formed, what characteristics they have, and how their formation can be inhibited, have been targeted in many studies thus far. In all of such studies, thioflavin T (ThT) fluorescence assay is used to qualify the amyloid aggregates and the inhibitory effect of polyphenolic small molecules. Among the proteins with the potential of the aggregation in vitro, hen egg white lysozyme (HEWL) is much used, and on the other hand, curcumin, a known polyphenol, has a potential to inhibit the aggregation process. However, whether curcumin affects the aggregation process or not, ThT fluorescence is biased in the presence of curcumin because it displays an enhanced absorption at the excitation wavelength of ThT. To address this problem and to qualify the aggregation more accurate, it is recommended to use Nile red (NR) anisotropy as an alternative fluorescence-based method which considers molecular sizes, not emissions. Since NR, as bound to amyloid fibrils, fluoresces significantly beyond the range of curcumin, NR anisotropy can further minimize the interference effect of curcumin.

[en] Proliposomes are dry phospholipid-based particles in which bioactives can be entrapped, and that can produce liposomal suspensions if adequately hydrated. In our study, curcumin and cholecalciferol were incorporated in proliposomes obtained by coating of micronized sucrose. Different mass ratios of Lipoid S40 and Phospholipon 90H were used to produce the proliposomes. The powders were structurally characterized and bioactives content were analyzed over 60 days of storage. Curcumin and cholecalciferol amounts in F100CV formulation were 100 and 98.7% of their initial amount, respectively. Strucutral characterization showed bioactives were successfully incorporated in concentrations compatible with recommended daily dosages. (Author)

[en] It is widely accepted that accumulation of extracellular glutamate mediates neuronal injuries in a number of neurological disorders via binding glutamate receptors. However, usage of the glutamate receptor antagonists aimed to prevent glutamate excitotoxicity is still controversial. As a polyphenol natural product, curcumin, has been implied multiple bioactivities. In this study, we explored whether the silent information regulator 1 (SIRT1)-peroxisome proliferator-activated receptor-coactivator 1α (PGC1α) pathway participated in the protection of curcumin against glutamate excitotoxicity. The cultured primary cortical neurons were treated with glutamate to set up a neuronal excitotoxicity model. The MTT and TUNEL methods were employed to measure cell viability and apoptosis, respectively. The mitochondrial function, the expression levels of SIRT1, PGC1α and acetylated PGC1α (ac-PGC1α) were measured to explore the mechanism of curcumin against glutamate excitotoxicity. The results showed that glutamate significantly induced cell death and apoptosis, which was blocked by pretreatment with curcumin. Meanwhile, curcumin preserved mitochondrial function, increased the expression level of SIRT1 and reduced the level of ac-PGC1α in the presence of glutamate. These results suggest that SIRT1-mediated deacetylation of PGC1α attributes to the neuroprotection of curcumin against glutamate excitotoxicity. - Highlights: • Curcumin attenuates glutamate induced cell death and apoptosis in cultured neurons. • Curcumin preserves mitochondrial function in the presence of glutamate. • Curcumin enhanced the expression of SIRT1 in the glutamate rich environment. • SIRT1-mediated deacetylation of PGC1α attributes to the neuroprotection of curcumin.

[en] The medicinal pigment curcumin cannot be employed as a drug due to lack of aqueous solubility whereas microemulsion can increase its bioavailability. Study of the interaction of nanoparticles with biologically active molecules such as curcumin is required for successful implementation of nanotechnology in medicine. Our study may provide detailed insight in using this system for bioimaging applications. (author)

[en] The article discusses the results of studies on the development of some therapeutic compositions with various biologically active ingredients such as curcumin, epigallocatechin gallate, piperine and gynestein for antitumor activity. It has been shown that complexes of curcumin with hyaluronic acid and epigallocatechin gallate in vitro have pronounced antitumor activity compared to known analogues. (author)

[en] Turmeric (Curcuma longa L.) is an economically and medicinally important spice crop. Curcumin, a major bioactive compound present in its rhizome imparts therapeutic properties to turmeric. Due to huge demand, development of novel turmeric cultivars with high yield and curcumin content is essential. In vitro mutagenesis has proved to be a valuable method for improving vegetatively propagated crops like turmeric. The present study was conducted to induce microrhizome in turmeric shoot cultures using gamma radiation and field assessment of these plantlets was carried out for improved yield and curcumin content. In vitro shoot cultures of turmeric were exposed to different doses of gamma radiation (0,5,10,15,20,25,30,35,40,45 and 50Gy). Further, shoot cultures of turmeric were exposed with the optimized gamma-irradiation dose. A detailed comparative field evaluation of microrhizome-producing plants, non-irradiated in vitro plants and conventional rhizome-raised plants was carried out for improvedyield and curcumin content. In vitro turmeric shoots exposed at 20-25Gy produced maximum microrhizomes after 30 days of irradiation. Shoots producing microrhizomes were superior in height, produced more leaves with enlarged size compared to the control. Field assessment performance of microrhizome producing plants in terms of yield and curcumin content was better than the other two. These plants produced higher number of mother rhizomes (8-10) per plant with average yield of 2.1kg/plant, non-irradiated plants produced (5-6) mother rhizomes with average yield 1.2 kg/plant and rhizome raised plants produced (5-7) mother rhizomes with an average yield of 1.5 kg /plant respectively. Curcumin content was also more in microrhizomes producing plants as compared to the other two. Microrhizome induction and growth rate of in vitro plantlets producing microrhizomes indicate that gamma irradiation at 20-25Gy effectively improves productivity in turmeric. Better recovery of curcumin vis-à-vis rhizome weight was the main advantage of in vitro microrhizome induction. (author)

[en] Highlights: • We find curcumin can rectify the fate of TSPCs in a pathological environment. • Controlled-release curcumin is a possible therapeutic strategy for tendon disease. • This study is an example of “old drug, new trick”. -- Abstract: Tendon calcification is a common but intractable problem leading to pain and activity limitation when injury or tendinopathy progresses into the late stage. This is because tendon stem/progenitor cells (TSPCs) can undergo aberrant osteogenic differentiation under inflammatory conditions. This study aims to investigate the effect of curcumin, a natural anti-inflammatory agent, on regulating the differentiation of TSPCs in tendon calcification. With inflammatory stimulation, TSPCs showed higher alkaline phosphatase activity and more frequent formation of mineralized nodules which were verified in the culture system; however, curcumin significantly alleviated these pathological changes. In in vivo function analysis, chitosan microsphere-encapsulated curcumin was delivered to injured sites of rat tendon ectopic calcification model. The inflammation in the tendon tissues of the curcumin group was significantly relieved. Controlled-release curcumin partially rescued tendon calcification and enhanced tendon regeneration in animal model. This study demonstrates that controlled-release curcumin can manipulate the fate decision of TSPCs, and that it promotes the tenogenesis and inhibits the osteogenesis of TSPCs in a pathological microenvironment, which provides a possible new therapeutic strategy for tendon disease.