The Bright Side of Curcumin: A Narrative Review of Its Therapeutic Potential in Cancer Management.

Curcumin, a polyphenolic compound derived from Curcuma longa, exhibits significant therapeutic potential in cancer management. This review explores curcumin's mechanisms of action, the challenges related to its bioavailability, and its enhancement through modern technology and approaches. Curcumin demonstrates strong antioxidant and anti-inflammatory properties, contributing to its ability to neutralize free radicals and inhibit inflammatory mediators. Its anticancer effects are mediated by inducing apoptosis, inhibiting cell proliferation, and interfering with tumor growth pathways in various colon, pancreatic, and breast cancers. However, its clinical application is limited by its poor bioavailability due to its rapid metabolism and low absorption. Novel delivery systems, such as curcumin-loaded hydrogels and nanoparticles, have shown promise in improving curcumin bioavailability and therapeutic efficacy. Additionally, photodynamic therapy has emerged as a complementary approach, where light exposure enhances curcumin's anticancer effects by modulating molecular pathways crucial for tumor cell growth and survival. Studies highlight that combining low concentrations of curcumin with visible light irradiation significantly boosts its antitumor efficacy compared to curcumin alone. The interaction of curcumin with cytochromes or drug transporters may play a crucial role in altering the pharmacokinetics of conventional medications, which necessitates careful consideration in clinical settings. Future research should focus on optimizing delivery mechanisms and understanding curcumin's pharmacokinetics to fully harness its therapeutic potential in cancer treatment.

Synthesis, Crystal Structure, and Photophysical Properties of Bromothiophene-Functionalized BF2-Curcuminoid as a Versatile Building Block.

A novel bromothiophene-functionalized BF2-curcuminoid (BTC-BF2) is synthesized by Knoevenagel condensation reaction. The structure of BTC-BF2 is determined by 1H-nuclear magnetic resonance (1H NMR), 13C-nuclear magnetic resonance (13C NMR), and high-resolution mass spectrometry (HRMS). Moreover, a nearly coplanar single crystal structure is successfully obtained and form a mesh structure through intermolecular multiple C─H···F hydrogen bond interactions. As expected, as-prepared BTC-BF2 exhibits solvent-dependent photophysical properties in solvents with different polarity and an intense red solid-state fluorescence. Density functional theory calculations further verify the relationships between its intrinsic electronic features and the photophysical properties. For its potential application aspect, BTC-BF2 shows a certain ability to generate singlet oxygen under irradiation with 530 nm green light. Moreover, BTC-BF2 can be utilized as versatile building block to construct novel far-red or NIR BF2-curcuminoid complexes for widely biological applications.

[Corrigendum] Next­generation sequencing analysis reveals that MTH­3, a novel curcuminoid derivative, suppresses the invasion of MDA­MB­231 triple­negative breast adenocarcinoma cells.

Subsequently to the publication of the article, an interested reader drew to the authors' attention that, in Fig. 2A on p. 5, the 'Control  (24 h)' and 'MTH­3 (1 µM; 24 h)' data panels contained partially overlapping data, such that they appeared to have been derived from the same original source. The authors have examined their original data, and realized that this error arose inadvertently as a consequence of having compiled this figure incorrectly. The revised version of Fig. 2, featuring the data from one of the repeated experiments in Fig. 2A, is shown below. The revised data shown for this figure do not affect the overall conclusions reported in the paper. The authors apologize to the Editor of Oncology Reports and to the readership for any inconvenience caused. [Oncology Reports 46: 133, 2021; DOI: 10.3892/or.2021.8084].

Curcuminoid PBPD induces cuproptosis and endoplasmic reticulum stress in cervical cancer via the Notch1/RBP-J/NRF2/FDX1 pathway.

Curcumin has been shown to have antitumor properties, but its low potency and bioavailability has limited its clinical application. We designed a novel curcuminoid, [1-propyl-3,5-bis(2-bromobenzylidene)-4-piperidinone] (PBPD), which has higher antitumor strength and improves bioavailability. Cell counting kit-8 was used to detect cell activity. Transwell assay was used to detect cell invasion and migration ability. Western blot and quantitative polymerase chain reaction were used to detect protein levels and their messenger RNA expression. Immunofluorescence was used to detect the protein location. PBPD significantly inhibited the proliferation of cervical cancer cells, with an IC50 value of 4.16 µM for Hela cells and 3.78 µM for SiHa cells, leading to the induction of cuproptosis. Transcriptome sequencing analysis revealed that PBPD significantly inhibited the Notch1/Recombination Signal Binding Protein for Immunoglobulin kappa J Region (RBP-J) and nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathways while upregulating ferredoxin 1 (FDX1) expression. Knockdown of Notch1 or RBP-J significantly inhibited NRF2 expression and upregulated FDX1 expression, leading to the inhibition of nicotinamide adenine dinucleotide phosphate activity and the induction of oxidative stress, which in turn activated endoplasmic reticulum stress and induced cell death. The overexpression of Notch1 or RBP-J resulted in the enrichment of RBP-J within the NRF2 promoter region, thereby stimulating NRF2 transcription. NRF2 knockdown resulted in increase in FDX1 expression, leading to cuproptosis. In addition, PBPD inhibited the acidification of tumor niche and reduced cell metabolism to inhibit cervical cancer cell invasion and migration. In conclusion, PBPD significantly inhibits the proliferation, invasion, and migration of cervical cancer cells and may be a novel potential drug candidate for treatment of cervical cancer.

Diacetylcurcumin: a novel strategy against Enterococcus faecalis biofilm in root canal disinfection.

Aim: We evaluated Diacetylcurcumin (DAC), a derivative of curcumin, for its antibacterial and antibiofilm properties against Enterococcus faecalis. Methods: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration were determined, along with antibiofilm potential and toxicity in Galleria mellonella. Additionally, in silico computational analysis was performed to understand its mechanisms of action. Results & conclusion: DAC demonstrated significant antibacterial effects, with MIC and MBC values of 15.6 and 31.25 µg/ml, respectively, and reduced biofilm formation. A synergistic effect, reducing biofilm by 77%, was observed when combined with calcium hydroxide. G. mellonella toxicity tests confirmed DAC's safety at tested concentrations, suggesting its potential for use in root canal disinfection products.

Diacetylcurcumin (DAC) comes from turmeric, a natural spice often used in food. DAC may have the ability to fight germs, including the bacteria Enterococcus faecalis. We tested DAC's ability to kill E. faecalis and stopping the formation of films of the bacteria. We found that a small amount of DAC did kill E. faecalis. When used with calcium hydroxide, DAC works even better to reduce the formation of bacterial films by 77%. DAC is safe to be used on teeth, so may be a useful ingredient for preserving mouth health.

Curcumin piperidone derivatives induce caspase-dependent apoptosis and suppress miRNA-21 expression in LN-18 human glioblastoma cells.

BACKGROUND: Previously, we have reported on the two curcuminoid analogues with piperidone derivatives, namely FLDP-5 and FLDP-8 have more potent anti-proliferative and anti-migration effects than curcumin. In this study, we further investigated the mode of cell death and the mechanism involved in the cell death process induced by these analogues on human glioblastoma LN-18 cells. RESULTS: The FLDP-5 and FLDP-8 curcuminoid analogues induced LN-18 cell death through apoptosis in a concentration-dependent manner following 24 h of treatment. These analogues induced apoptosis in LN-18 cells through significant loss of mitochondrial mass and mitochondrial membrane potential (MMP) as early as 1-hour of treatment. Interestingly, N-acetyl-l-cysteine (NAC) pretreatment did not abolish the apoptosis induced by these analogues, further confirming the cell death process is independent of ROS. However, the apoptosis induced by the analogues is caspases-dependent, whereby pan-caspase pretreatment inhibited the curcuminoid analogues-induced apoptosis. The apoptotic cell death progressed with the activation of both caspase-8 and caspase-9, which eventually led to the activation of caspase-3, as confirmed by immunoblotting. Moreover, the existing over-expression of miRNA-21 in LN-18 cells was suppressed following treatment with both analogues, which suggested the down-regulation of the miRNA-21 facilitates the cell death process. CONCLUSION: The FLDP-5 and FLDP-8 curcuminoid analogues downregulate the miRNA-21 expression and induce extrinsic and intrinsic apoptotic pathways in LN-18 cells.

Near infra-red absorbing Quinolizidine fused curcuminoid-BF2 chelate and its applications in photodynamic therapy using MCF-7 and A549 cells.

Metal-free near-infrared absorbing photosensitizers (PS) have been considered promising candidates for photodynamic therapy. Curcumin, curcuminoid, and its derivatives have therapeutic values due to their anti-inflammatory, antifungal, and antiproliferative properties. Curcuminoid-BF2 chelates have also been studied as cell imaging probes, however, their applications in photodynamic therapy are rare. In this article, we describe the synthesis and therapeutic evaluation of quinolizidine fused curcuminoid-BF2 chelate (Quinolizidine CUR-BF2) containing an acid-sensitive group. This donor-acceptor-donor curcuminoid-BF2 derivative exhibits absorption and emission in the deep red region with an absorption band maximum of ∼647 nm and a weak emission band at approximately 713 nm. It is interesting to note that this derivative has a high molar extinction coefficient (164,655 M-1cm-1). Quinolizidine CUR-BF2 possesses intramolecular charge transfer properties, facilitating the production of singlet oxygen (1O2), which plays a crucial role in cell death. Additionally, Quinolizidine CUR-BF2 can enable the selective release of active ingredients in an acidic medium (pH 5). Furthermore, the nanoaggregates of PS were prepared by encapsulating Quinolizidine CUR-BF2 within Pluronic F127 block co-polymer for better water-dispersibility and enhanced cellular uptake. Dark cytotoxicity of nanoaggregates was found to be negligible, whereas they exhibited significant photoinduced cytotoxicity towards cancer cells (MCF-7 and A549) under irradiation of 635 nm light. Further, the cell death pathway using Quinolizidine CUR-BF2 nanoaggregates as PS is found to occur through apoptosis. Specifically, the present study deals with the successful preparation of Quinolizidine CUR-BF2 nanoaggregates for enhanced water-dispersibility and cellular uptake as well as the efficacy evaluation of developed nanoaggregates for photodynamic therapy.

Interaction of Thiol Antioxidants with α,ß-Unsaturated Ketone Moiety: Its Implication for Stability and Bioactivity of Curcuminoids.

Many biological functions of curcumin have been reported. As certain bioactivities of curcumin are eliminated by antioxidants, reactive oxygen species generated by curcumin have been suggested as a relevant mechanism. In the present study, the effects of different types of antioxidants on the stability and bioactivities of curcumin were analyzed. High concentrations (>4 mM) of thiol antioxidants, including N-acetylcysteine (NAC), glutathione (GSH), and ß-mercaptoethanol, accelerated the decomposition of curcumin and other curcuminoids; the submillimolar levels (<0.5 mM) of GSH and NAC rather improved their stability. Ascorbic acid or superoxide dismutase also stabilized curcumin, regardless of their concentration. The cellular levels and bioactivities of curcumin, including its cytotoxicity and the induction of heme oxygenase-1, were significantly reduced in the presence of 8 mM of GSH and NAC. The effects were enhanced in the presence of submillilmolar GSH and NAC, or non-thiol antioxidants. The present results indicate that antioxidants with a reduced thiol group could directly interact with the α,ß-unsaturated carbonyl moiety of curcuminoids and modulate their stability and bioactivity.

Curcuminoid Chalcones: Synthesis and Biological Activity against the Human Colon Carcinoma (Caco-2) Cell Line.

BACKGROUND: There are many current scientific reports on the synthesis of various derivatives modelled on the structure of known small-molecular and natural bioactive compounds. Curcuminoid chalcones are an innovative class of compounds with significant therapeutic potential against various diseases and they perfectly fit into the current trends in the search for new biologically active substances. AIM: The aim of this study was to design and synthesise a series of curcuminoid chalcones. OBJECTIVE: The objective of this scientific paper was to synthesise twelve curcuminoid chalcones and confirm their structures using spectral methods. Additionally, the biological activity of three of the synthesised compounds was evaluated using various assays, and their anticancer properties and toxicity were studied. METHODS: The proposed derivatives were obtained via the Claisen-Schmidt reaction of selected acetophenones and aldehydes in various conditions using both classical methods: the solutions and solvent-free microwave (MW) or ultrasound (US) variants. The most optimal synthetic method for the selected curcuminoid chalcones was the classical Claisen-Schmidt condensation in an alkaline (NaOH) medium. Spectral methods were used to confirm the structures of the compounds. The resazurin reduction assay, caspase-3 activity assay, and RT-qPCR method were performed, followed by measurements of the intracellular reactive oxygen species (ROS) level and the lactate dehydrogenase (LDH) release level. RESULTS: Twelve designed curcuminoid chalcones were successfully synthesized and structurally confirmed by NMR, MS, and IR spectroscopy. Examination of the anticancer activity was carried out for the three most interesting chalcone products. CONCLUSION: The results suggested that compound 3a increased the metabolism and/or proliferation of the human colon carcinoma (Caco-2) cell line, while compounds 3b and 3f showed significant toxicity against the Caco-2 cell line. Overall, the preliminary results suggested that compound 3b exhibited the most favorable anticancer activity.

Differential gene expression analysis under salinity stress in the selected turmeric (Curcuma longa L.) cultivars for curcuminoid biosynthesis.

BACKGROUND: Curcuminoids are the phenolic compounds found exclusively in turmeric. Their presence is known to increase immunity and resistance against certain cancers and neurological disorders in humans also, protecting the plant itself against salinity stress. METHODS: In this experiment, we studied the expression levels of MAPK1 and DCS genes, their curcuminoid biosynthesis under salinity stress conditions so that the impact of individual genes can be understood using semi- quantitative PCR. RESULTS: The expressions of the genes with respect to curcuminoid biosynthesis showed fluctuations in their band intensity values due to the production of curcuminoids, which is initiated first in the leaves followed by the rhizomes. Not all the genes responsible for the curcuminoid biosynthesis show positive regulation under salt stress conditions which is observed in response to the severity of the stress imposed on the cultivars. CONCLUSIONS: In our findings, both the genes MAPK1 and DCS were down-regulated for curcuminoid biosynthesis compared to their controls in both the cultivars Vallabh Sharad and Selection 1.

Curcuminoid Chalcones: Synthesis, Stability, and New Neuroprotective and Sonosensitising Activities.

The primary purpose of this work was to design and obtain a series of curcuminoid chalcone-NSAID hybrid derivatives. The ester-type hybrid compounds with ibuprofen (i), ketoprofen (ii), and naproxen (iii) were obtained in two ways, using the Claisen-Schmidt reaction and the Steglich esterification reaction. The designed molecules were successfully synthesised, and FT-IR, MS, and NMR spectroscopy confirmed their structures. Moreover, the cytotoxic effect of the sonodynamic therapy and the anti-inflammatory, antioxidant, and anticholinergic properties of some curcuminoid chalcones and curcuminoid chalcones hybrids were evaluated. The curcuminoid chalcone derivatives showed promising neuroprotective activity as sonosensitisers for sonodynamic therapy in the studied cell lines. Additionally, the stability of the ester-type hybrid compounds with promising activity was determined. The RP-HPLC method was used to observe the degradation of the tested compounds. Studies have shown that structural isomers of ester-type hybrid compounds (3ai, 3bi) are characterised by a similar susceptibility to degradation factors, i.e., they are extremely unstable in alkaline environments, very unstable in acidic environments, unstable in neutral environments, practically stable in oxidising environments, and photolabile in solutions and in the solid phase. These compounds maintain adequate stability in environment at pH 1.2 and 6.8, which may make them good candidates for developing formulations for oral administration.

Modified Curcuminoid-Rich Extract Liposomal CRE-SDInhibits Osteoclastogenesis via the Canonical NF-κB Signaling Pathway.

Curcuminoids, namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin, are the major active compounds found in Curcuma longa L. (turmeric). Although their suppressive effects on bone resorption have been demonstrated, their pharmacokinetic disadvantages remain a concern. Herein, we utilized solid dispersion of a curcuminoid-rich extract (CRE), comprising such curcuminoids, to prepare CRE-SD; subsequently, we performed liposome encapsulation of the CRE-SD to yield liposomal CRE-SD. In vitro release assessment revealed that a lower cumulative mass percentage of CRE-SD was released from liposomal CRE-SD than from CRE-SD samples. After culture of murine RANKL-stimulated RAW 264.7 macrophages, our in vitro examinations confirmed that liposomal CRE-SD may impede osteoclastogenesis by suppressing p65 and IκBα phosphorylation, together with nuclear translocation and transcriptional activity of phosphorylated p65. Blind docking simulations showed the high binding affinity between curcuminoids and the IκBα/p50/p65 protein complex, along with many intermolecular interactions, which corroborated our in vitro findings. Therefore, liposomal CRE-SD can inhibit osteoclastogenesis via the canonical NF-κB signaling pathway, suggesting its pharmacological potential for treating bone diseases with excessive osteoclastogenesis.

High-shear wet agglomeration process for enriching cornstarch with curcumin and vitamin D3 co-loaded lyophilized liposomes.

Curcumin and vitamin D3 are bioactive molecules of great importance for the food industry. However, their low stability in several processing conditions hampers their proper incorporation into powdered food formulations. This study proposes the enrichment of a common raw material (cornstarch) with curcumin and vitamin D3 by using high-shear wet agglomeration. The bioactives were initially encapsulated into liposome dispersions and then subjected to lyophilization. The resulting dried vesicles were later incorporated into cornstarch by wet agglomeration using maltodextrin as the binder solution. The phospholipid content and the amount of added liposomes were evaluated to characterize the enriched cornstarch samples. The lyophilized vesicles showed a high retention rate of 99 % for curcumin and vitamin D3, while the enriched cornstarch samples retained above 96 % (curcumin) and 98 % (vitamin D3) after 30 days of controlled storage. All in all, the presence of dried liposomes improved the flowability and delayed retrogradation phenomenon in agglomerated cornstarch. Therefore, this study introduced a novel and reliable method of incorporating hydrophobic and thermosensitive molecules into powdered food formulations by using readily available materials and a straightforward high-shear wet agglomeration process.

Structure-activity relationship of dibenzylideneacetone analogs against the neglected disease pathogen, Trypanosoma brucei.

Trypanosoma brucei is a protozoan parasite that causes Human African Trypanosomiasis (HAT), a neglected tropical disease (NTD) that is endemic in 36 countries in sub-Saharan Africa. Only a handful drugs are available for treatment, and these have limitations, including toxicity and drug resistance. Using the natural product, curcumin, as a starting point, several curcuminoids and related analogs were evaluated against bloodstream forms of T. b. brucei. A particular subset of dibenzylideneacetone (DBA) compounds exhibited potent in vitro antitrypanosomal activity with sub-micromolar EC50 values. A structure-activity relationship study including 26 DBA analogs was initiated, and several compounds exhibited EC50 values as low as 200 nM. Cytotoxicity counter screens in HEK293 cells identified several compounds having selectivity indices above 10. These data suggest that DBAs offer starting points for a new small molecule therapy of HAT.

Optimization of ethanol-modified subcritical water extraction of curcuminoids from turmeric (Curcuma longa L.) rhizomes: Comparison with conventional techniques.

Subcritical solvent extraction (SSE) as ethanol-modified subcritical water extraction (SWE) was applied to extract curcuminoids from turmeric (Curcuma longa L.) rhizomes. RSM-CCD was employed to evaluate the influential factors including temperature (90-150 °C), flow rate (1-4 mL/min), and ethanol concentration (25-75 wt%) on the extraction yield. The optimum condition was 90 °C, 4 mL/min, and 25 wt% with the extraction yield of 4.12 wt% (db). Applying ethanol as a polarity-tuning parameter enabled operations at lower temperatures, which prevented thermal degradation. The SSE optimum experiment was compared with Soxhlet, ultrasound-assisted extraction (UAE) and conventional solvent extraction (CSE), both with the ethanol-water mixture (25 wt%). Their yields were 2.71, 0.85, and 0.84 wt% (db), respectively. The higher yield of SSE was related to the higher solubility of curcuminoids due to the more appropriate adjustment of solvent polarity by a decrease in the dielectric constant with a rise in the operating temperature.

MCF-7 cells lack the expression of Caspase-3.

With great interest, we read the paper "Chitosan nano-vehicles as biocompatible delivering tools for a new Ag(I)curcuminoid-Gboxin analog complex in cancer and inflammation therapy" published in the International Journal of Biological Macromolecules. In Elbehairi's report, the human breast carcinoma line MCF-7 were used in the in vitro cytotoxic analysis test of the curcuminoid conjugate and its silver(I) complex. They found that Ag(I)FLLL49-GbA could induce highly significant up-regulation of caspase-3, tumor suppressor proteins P53, and Bax after the 48 h of treatment in MCF-7 cells (Fig. 9), and the expression of caspase-3 was analyzed by western blot assay. However, it's well known that the MCF-7 breast carcinoma line do not express caspase-3. The lack of caspase-3 in MCF-7 cells is caused by a 47-base pair deletion within exon 3 of the CASP-3 gene resulting in the skipping of this exon during pre-mRNA splicing and introduction of a premature stop codon at position 42 that completely abrogates translation of the CASP-3 mRNA. Therefore, the detection of a caspase-3 protein in caspase-3 deficient MCF-7 cells in this study made us confused. We appreciate the authors' efforts in investigating the effects of chitosan nano-vehicles as biocompatible delivering tools for a new Ag(I)curcuminoid-Gboxin analog complex in cancer and inflammation therapy. Nevertheless, we sincerely suggest that appropriate modification may further solidify the findings of the study.

Dermocosmetic evaluation of a nutricosmetic formulation based on Curcuma.

Endogenous and exogenous factors can alter the skin layer and appearance, determining skin aging. The extracts and isolated molecules from food matrixes can be used to formulate "healthy" antiaging cosmetics. Two different cosmetic approaches can be used to achieve the antiaging effect. It is possible to use topical products based on food extract (cosmeceutical approach) or take a food supplement and apply a topical cosmetic product based on food extract on the surface to be treated (nutricosmetic approach). This work evaluated in vivo the antiaging potential of a nutricosmetic formulation (cream + food supplement) and a cosmeceutical cream based on Curcuma. The choice of the commercial Curcuma extract to be used for experimental purposes was based on the curcuminoid content determined by an HPLC test. Curcuminoids are the bioactive compounds responsible for Curcuma's antioxidant and antiinflammatory properties. Their levels in Curcuma extracts vary according to the storage condition, variety, and pedoclimatic cultivation conditions. The Tewameter® TM300 was used to evaluate the Trans Epidermal Water Loss (TEWL), the Corneometer® CM 825 to determine the moisturizing effect, the Cutometer® to estimate the skin firmness and elasticity, the Dermascan to assess the collagen index, and the Visioface® 1000D to evaluate the wrinkles. The nutricosmetic product showed potential as moisturizing, anti-age, and anti-wrinkle action better than the cosmeceutical product alone.

Solubilized curcuminoid complex prevents extensive immunosuppression through immune restoration and antioxidant activity: Therapeutic potential against SARS-CoV-2 (COVID-19).

The therapeutic benefits of curcuminoids in various diseases have been extensively reported. However, little is known regarding their preventive effects on extensive immunosuppression. We investigated the immunoregulatory effects of a curcuminoid complex (CS/M), solubilized with stevioside, using a microwave-assisted method in a cyclophosphamide (CTX)-induced immunosuppressive mouse model and identified its new pharmacological benefits. CTX-treated mice showed a decreased number of innate cells, such as dendritic cells (DCs), neutrophils, and natural killer (NK) cells, and adaptive immune cells (CD4 and CD8 T cells) in the spleen. In addition, CTX administration decreased T cell activation, especially that of Th1 and CD8 T cells, whereas it increased Th2 and regulatory T (Treg) cell activations. Pre-exposure of CS/M to CTX-induced immunosuppressed mice restored the number of innate cells (DCs, neutrophils, and NK cells) and increased their activity (including the activity of macrophages). Exposure to CS/M also led to the superior restoration of T cell numbers, including Th1, activated CD8 T cells, and multifunctional T cells, suppressed by CTX, along with a decrease in Th2 and Treg cells. Furthermore,CTX-injected mice pre-exposed to CS/M were accompanied by an increase in the levels of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), which play an essential role against oxidative stress. Importantly, CS/M treatment significantly reduced viral loads in severe acute respiratory syndrome coronavirus2-infected hamsters and attenuated the gross pathology in the lungs. These results provide new insights into the immunological properties of CS/M in preventing extensive immunosuppression and offer new therapeutic opportunities against various cancers and infectious diseases caused by viruses and intracellular bacteria.

Antibacterial and Antiviral Properties of Tetrahydrocurcumin-Based Formulations: An Overview of Their Metabolism in Different Microbiotic Compartments.

In this review, the basic metabolic characteristics of the curcuminoid tetrahydrocurcumin (THC) at the level of the intestinal microbiota were addressed. Special attention was given to the bactericidal effects of one of the THC-phospholipid formulations, which has shown greater bioavailability and activity than pure THC. Similarly, quinoline derivatives and amino acid conjugates of THC have also shown antibacterial effects in the gut. The microbial effect of pure THC is particularly pronounced in pathophysiological conditions related to the function of the intestinal microbiota, such as type II diabetes. Furthermore, the antiviral characteristics of Cur compared to those of THC are more pronounced in preventing the influenza virus. In the case of HIV infections, the new microemulsion gel formulations of THC possess high retention during preventive application in the vagina and, at the same time, do not disturb the vaginal microbiota, which is critical in maintaining low vaginal pH. Based on the reviewed literature, finding new formulations of THC which can increase its bioavailability and activity and emphasize its antibacterial and antiviral characteristics could be very important. Applying such THC formulations in preventing and treating ailments related to the microbiotic compartments in the body would be beneficial from a medical point of view.

Impact of Green Extraction on Curcuminoid Content, Antioxidant Activities and Anti-Cancer Efficiency (In Vitro) from Turmeric Rhizomes (Curcuma longa L.).

Turmeric (Curcuma longa L.) powder is widely used as a spice and seasoning in Asian countries. This study investigated the effect of turmeric extracts on the anticancer activity of Huh7 and HCT 116 cells. The curcumin bioactive compounds were extracted using various methods such as microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and traditional extraction (TDE). The yield of dried extracts from MAE was found to be the highest at 17.89%, followed by UAE and TDE, with 11.34% and 5.54%, respectively. Antioxidant activities such as TPC, DPPH and FRAP from MAE were higher than those of UAE and TDE. The total curcuminoid contents from the novel extractions were higher than those from traditional extraction methods. For instance, curcuminoid contents from MAE, UAE and TDE were 326.79, 241.17 and 215.83 mg/g, respectively. Due to having the highest bioactive compounds and extraction yield, turmeric extract from MAE was used to investigate the potential anticancer properties. The extract showed significant cytotoxic potential against the human liver (Huh7) and human colon (HCT116) cell lines, in concentrations ranging from 31.25 to 1000.00 µg/mL. Turmeric extracts using MAE have potential anticancer effects on Huh7 and HCT116 cells. This study serves as scientific data for the chemotherapeutic properties of turmeric extracts and their use as functional ingredients.