Ixora coccinea Linn.: Traditional uses, phytochemistry and pharmacology

Floral Fusion: Unravelling the Potent Blend of Ixora coccinea and Rhododendron arboreum for Health and Safety Benefits

OBJECTIVE

Ixora coccinea and Rhododendron arboreum are known for their traditional medicinal uses due to their diverse phytochemicals and pharmacological effects, which have attracted the interest of many researchers. This study aims to evaluate the antioxidant, anti-inflammatory, and cytotoxic effects of their combined extracts.

METHODS

In vitro antioxidant activity against reactive oxygen species (ROS) was measured using the ferric-reducing ability of plasma (FRAP), nitric oxide (NO), and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays, while anti-inflammatory effects were assessed via the membrane stabilization method. Docking studies were performed to evaluate the interaction of phytochemicals - anthocyanins, quercetin, and ursolic acid, which are present in these plants - with nuclear factor kappa B (NF-κB), cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2). Standard protocols were used to evaluate embryotoxicity using the brine shrimp model and cytotoxicity using the zebrafish model, which is crucial for determining safe clinical dosages.

RESULTS

The analysis revealed diverse bioactive compounds, including anthocyanins, quercetin, and ursolic acid. The formulation effectively inhibited ROS production at lower concentrations (inhibitory concentration 50%, or IC50 value ~2.8 µg/mL), indicating their potential for managing oxidative stress. Quercetin demonstrated the strongest interaction with all tested proteins, particularly NF-kB. Cytotoxicity and embryotoxicity assays revealed a dose-dependent effect (lethal concentration 50%, or LC50 value 82.4 µg/mL), with no adverse effects on developing embryos at the tested doses (5-80 µg/mL), suggesting the extracts are safe for clinical use, even during pregnancy.

CONCLUSION

The combined extracts of I. coccinea and R. arboreum exhibit potent antioxidant and anti-inflammatory effects without causing cytotoxic or embryotoxic effects, even at higher concentrations. This indicates their potential for safe clinical application in treating oxidative and inflammatory diseases.

Climate-Affected Australian Tropical Montane Cloud Forest Plants: Metabolomic Profiles, Isolated Phytochemicals, and Bioactivities

The Australian Wet Tropics World Heritage Area (WTWHA) in northeast Queensland is home to approximately 18 percent of the nation's total vascular plant species. Over the past century, human activity and industrial development have caused global climate changes, posing a severe and irreversible danger to the entire land-based ecosystem, and the WTWHA is no exception. The current average annual temperature of WTWHA in northeast Queensland is 24 °C. However, in the coming years (by 2030), the average annual temperature increase is estimated to be between 0.5 and 1.4 °C compared to the climate observed between 1986 and 2005. Looking further ahead to 2070, the anticipated temperature rise is projected to be between 1.0 and 3.2 °C, with the exact range depending on future emissions. We identified 84 plant species, endemic to tropical montane cloud forests (TMCF) within the WTWHA, which are already experiencing climate change threats. Some of these plants are used in herbal medicines. This study comprehensively reviewed the metabolomics studies conducted on these 84 plant species until now toward understanding their physiological and metabolomics responses to global climate change. This review also discusses the following: (i) recent developments in plant metabolomics studies that can be applied to study and better understand the interactions of wet tropics plants with climatic stress, (ii) medicinal plants and isolated phytochemicals with structural diversity, and (iii) reported biological activities of crude extracts and isolated compounds.

In Vitro Evaluation of Extracts From Ixora Species for a Potential Phytosomal Formulation

Background Ixora species are perennial shrubs and flowering plants belonging to the family Rubiaceae. The leaf and flower parts of Ixora coccinea (I. coccinea) andIxora alba (I. alba) were aimed at isolating their active fractions. The present study was to determine in vitro antitumor activity against malignant melanoma cell lines for phytosome formulation. Materials and methods Two species, I. coccinea (red flowers and leaves) and I. alba (white flowers and leaves), were selected, and this study focused on determining the active fraction by comparing the in vitro antimicrobial and antioxidant potentials of petroleum ether, chloroform, ethyl acetate, and hydroalcoholic (ethanol:water, 70:30 v/v) extracts. The identified potent extract was subjected to in vitro anticancer activity in malignant melanoma cell lines. Results A phytochemical study revealed phytosterols, flavonoids, proteins, amino acids, alkaloids, carbohydrates, phenols, tannins, and diterpenes. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to evaluate the antioxidant effect of I. coccinea and I. alba leaf and flower extracts. In the DPPH assay, I. coccinea flower hydroalcoholic extract (ICFHA) had an IC50 value of 248.99 µg/mL, and I. coccinea leaf hydroalcoholic extract (ICLHA) had an IC50 value of 268.87 µg/mL. These two extracts had a lower value with a higher antioxidant effect. In the total antioxidant assay, I. coccinea leaf ethyl acetate extract (ICLEA) and I. coccinea leaf chloroform extract (ICLCE) have 77.4 ± 0.05 and 68.9 ± 0.03 mg of ascorbic acid equivalent per gm of extract, respectively. These two extracts exhibited a high antioxidant effect. The antimicrobial potential was evaluated using selected bacterial and fungal strains using the agar-well diffusion method. Petroleum ether and chloroform extracts of I. coccinea and I. alba leaves and flowers did not possess antimicrobial activity with any of the bacterial or fungal strains. An ethyl acetate extract and a hydroalcoholic extract of I. coccinea leaves and flowers showed antimicrobial activity against Enterococcus faecalis, Candida albicans, and Staphylococcus aureus. An ethyl acetate extract of I. coccinea flower and a hydroalcoholic extract of I. alba leaf showed a significant zone of inhibition when compared with standard chloramphenicol for all three selected strains, which may be due to the presence of active phytoconstituents. ICLHA showed a MIC of ≤300 µg/mL for Enterococcus faecalis and Staphylococcus aureus and ≤400 µg/mL for Candida albicans microbial strains. The high total flavonoid content was reported in ICLEA at 771.31 µg/mL and in I. coccinea flower ethyl acetate extract (ICFEA) at 694.69 µg/mL. High-performance thin layer chromatography (HPTLC) analysis showed a high quercetin (QCE) content in the ICLEA extract. To prove the in vitro skin anticancer activity, an MTT assay was performed for the ICLEA extract in a malignant melanoma cell line, and the IC50 value was reported as 7.96 µg/mL. Conclusion I. coccinea leaf ethyl acetate extract revealed a significant total flavonoid content in analysis through the aluminum chloride method, and the presence of a high QCE content was confirmed by HPTLC analysis. The in vitro skin anticancer activity of ICLEA was confirmed by the MTT assay; therefore, it was concluded that the ICLEA extract was a potent fraction and was selected to develop a phytosome.

Plants of the Rubiaceae Family with Effect on Metabolic Syndrome: Constituents, Pharmacology, and Molecular Targets

Metabolic syndrome (MetS) predisposes individuals to chronic non-communicable diseases (NCDs) like type 2 diabetes (T2D), non-alcoholic fatty liver disease, atherosclerosis, and cardiovascular disorders caused by systemic inflammation, intestinal dysbiosis, and diminished antioxidant ability, leading to oxidative stress and compromised insulin sensitivity across vital organs. NCDs present a global health challenge characterized by lengthy and costly pharmacological treatments. Complementary and alternative medicine using herbal therapies has gained popularity. Approximately 350,000 plant species are considered medicinal, with 80% of the world's population opting for traditional remedies; however, only 21,000 plants are scientifically confirmed by the WHO. The Rubiaceae family is promissory for preventing and treating MetS and associated NCDs due to its rich content of metabolites renowned for their antioxidative, anti-inflammatory, and metabolic regulatory properties. These compounds influence transcription factors and mitigate chronic low-grade inflammation, liver lipotoxicity, oxidative stress, and insulin resistance, making them a cost-effective non-pharmacological approach for MetS prevention and treatment. This review aims to collect and update data that validate the traditional uses of the Rubiaceae family for treating MetS and associated NCDs from experimental models and human subjects, highlighting the mechanisms through which their extracts and metabolites modulate glucose and lipid metabolism at the molecular, biochemical, and physiological levels.

The green synthesis of magnesium oxide nanocomposite-based solid phase for the extraction of arsenic, cadmium, and lead from drinking water

Solid-phase extraction (SPE) has attracted the attention of scientists because it can increase the selectivity and sensitivity measurements of analytes. Therefore, this study is designed to synthesise magnesium oxide nanoparticles (D-MgO-NPs) by an eco-friendly method using biogenic sources Duranta erecta followed by fabricating its chitosan-based polymeric composite (D-MgO-NC) for the SPE of heavy metals (HMs), i.e., arsenic (As), cadmium (Cd), and lead (Pb) from drinking water. Various analytical techniques were used for the surface characterization of D-MgO-NPs and D-MgO-NC. FTIR findings confirmed the formation of D-MgO-NC based on MgO association with the -OH/-NH2 of the chitosan. D-MgO-NC showed the smallest size of particles with rough surface morphology, followed by the crystalline cubic structure of MgO in its nanoparticle and composites. The synthesised D-MgO-NC was used as an adsorbent for the SPE of HMs from contaminated water, followed by their detection by atomic absorption spectrometry. Various experimental parameters, including pH, flow rate, the concentration of HMs, eluent composition, and volume, were optimised for the preconcentration of HMs. The limits of detection for As, Cd, and Pb of the proposed D-MgO-NC-based SPE method were found to be 0.008, 0.006, and 0.012 μm L-1, respectively. The proposed method has an enrichment factor and relative standard deviation of >200 and <5.0%, respectively. The synthesised D-MgO-NC-based SPE method was successfully applied for the quantitative detection of As, Cd, and Pb in groundwater samples, which were found in the range of 18.3 to 15.2, 3.20 to 2.49, and 8.20 to 6.40 μg L-1, respectively.

Biosynthesis and Analytical Characterization of Iron Oxide Nanobiocomposite for In-Depth Adsorption Strategy for the Removal of Toxic Metals from Drinking Water

The biosynthesis of the iron oxide nanoparticles was done using Ixoro coccinea leaf extract, followed by the fabrication of iron oxide nanobiocomposites (I-Fe3O4-NBC) using chitosan biopolymer. Furthermore, the synthesized I-Fe3O4-NPs and I-Fe3O4-NBC were characterized, and I-Fe3O4-NBC was applied to remove toxic metals (TMs: Cd, Ni, and Pb) from water. The characterization study confirmed that the nanostructure, porous, rough, crystalline structure, and different functional groups of chitosan and I-Fe3O4-NPs in I-Fe3O4-NBCs showed their feasibility for the application as excellent adsorbents for quantitative removal of TMs. The batch mode strategy as feasibility testing was done to optimize different adsorption parameters (pH, concentrations of TMs, dose of I-Fe3O4-NBC, contact time, and temperature) for maximum removal of TMs from water by Fe3O4-NBC. The maximum adsorption capacities using nanocomposites for Cd, Ni, and Pb were 66.0, 60.0, and 66.4 mg g-1, respectively. The adsorption process follows the Freundlich isotherm model by I-Fe3O4-NBC to remove Cd and Ni, while the Pb may be adsorption followed by multilayer surface coverage. The proposed adsorption process was best fitted to follow pseudo-second-order kinetics and showed an exothermic, favorable, and spontaneous nature. In addition, the I-Fe3O4-NBC was applied to adsorption TMs from surface water (%recovery > 95%). Thus, it can be concluded that the proposed nanocomposite is most efficient in removing TMs from drinking water up to recommended permissible limit.

Antimicrobial and biofilm inhibiting potential of an amide derivative [N-(2', 4'-dinitrophenyl)-3β-hydroxyurs-12-en-28-carbonamide] of ursolic acid by modulating membrane potential and quorum sensing against colistin resistant Acinetobacter baumannii

Acinetobacter baumannii is Gram-negative, an opportunistic pathogen responsible for life-threatening ventilator-associated pneumonia. World Health Organization (WHO) enlisted it as a priority pathogen for which therapeutic options need speculations. Biofilm further benefits this pathogen and aids 100-1000 folds more resistant against antimicrobials and the host immune system. In this study, ursolic acid (1) and its amide derivatives (2-4) explored for their antimicrobial and antibiofilm potential against colistin-resistant A. baumannii (CRAB) reference and clinical strains. Viability, crystal violet, microscopic, and gene expression assays further detailed the active compounds' antimicrobial and biofilm inhibition potential. Compound 4 [N-(2',4'-dinitrophenyl)-3β-hydroxyurs-12-en-28-carbonamide)], a synthetic amide derivate of ursolic acid significantly inhibits bacterial growth with MIC in the range of 78-156 μg/mL against CRAB isolates. This compound failed to completely kill the CRAB isolates even at 500 μg/mL concentration, suggesting the compound's anti-virulence and bacteriostatic nature. Short and prolonged exposure of 4 inhibited or delayed the bacterial growth at sub MIC, MIC, and 2× MIC, as evident in time-kill and post-antibacterial assay. It significantly inhibited and eradicated >70% of biofilm formation at MIC and sub MIC levels compared to colistin required in high concentrations. Microscopic analysis showed disintegrated biofilm after treatment with the 4 further strengthened its antibiofilm potential. Atomic force microscopy (AFM) hinted the membrane disrupting effect of 4 at MIC's. Further it was confirmed by DiBAC4 using fluorescence-activating cells sorting (FACS), suggesting a depolarized membrane at MIC. Gene expression analysis also supported our data as it showed reduced expression of biofilm-forming (bap) and quorum sensing (abaR) genes after treatment with sub MIC of 4. The results suggest that 4 significantly inhibit bacterial growth and biofilm mode of colistin-resistant A. baumannii. Thus, further studies are required to decipher the complete mechanism of action to develop 4 as a new pharmacophore against A. baumannii.

Amelioration of arsenic-induced oxidative stress in CHO cells by Ixora coccinea flower extract

Chronic exposure to inorganic arsenic creates various health problems. Ixora coccinea flower extract was investigated for its ability to protect against arsenic-induced cytotoxicity and genotoxicity in CHO cell line. MTT assay confirmed the efficacy of the extract in ameliorating arsenic-induced cytotoxicity. The value (48 mM) of 24 h inhibitory concentration (IC50) of sodium arsenate for CHO cells was obtained by MTT assay. Various free radical scavenging assays like DPPH, ABTS and nitric oxide scavenging assay confirmed antioxidant activity of the Ixora coccinea flower extract. Pretreatment of the extract significantly inhibited the arsenic-induced DNA damage (p < 0.01) in CHO cells. The extract administration significantly (p < 0.01) inhibited the intracellular ROS and depolarization of mitochondrial membrane induced by sodium arsenate. Ixora coccinea flower extract reduced oxidative stress in cells. Antioxidant enzymes like catalase and SOD activity was restored significantly (p < 0.01) in pretreated CHO cells. Ixora coccinea flower extract also exhibited the anti-apoptotic potential by decreasing the percentage apoptotic index (p < 0.01). These results may expand the applications of Ixora coccinea flowers as an alternative food with antioxidant properties and protective functions against arsenic (iAs) induced toxicological effects.

Ultrasound-assisted Extraction of Ursolic Acid from the Flowers of Ixora coccinia Linn (Rubiaceae) and Antiproliferative Activity of Ursolic Acid and Synthesized Derivatives

BACKGROUND

Ixora coccinea Linn (Rubiaceae) is an evergreen shrub with bright scarlet colored flowers found in several tropical and subtropical countries. It is used as an ornamental and medicinal plant. Phytochemical studies revealed that its major special metabolites are triterpene acids, such as ursolic and oleanolic acid.

OBJECTIVE

To evaluate the isolation of ursolic acid (UA) (1) from methanol extracts of I. coccinea flowers through two methodologies, to prepare four derivatives, and to evaluate the cytotoxic effect against six cancer cell lines.

MATERIALS AND METHODS

The UA was isolated from vegetal material by percolation at room temperature and by ultrasound-assisted extraction. The preparation of derivatives was performed according to literature methods, and the cytotoxic effects were evaluated using the MTT (3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) assay.

RESULTS

The most efficient extraction was achieved through ultrasound irradiation with a yield of 35% after KOH-impregnated silica in chromatography column. Furthermore, four derivatives (3, 5, 6, 7) of UA were prepared and evaluated, including 1, against two lung cancer (A549 and H460) and four leukemia (K562, Lucena, HL60, and Jurkat) cell lines. Generally, results showed that 1 and 7 were the most active compounds against the assayed cell lines. Also, the cytotoxic effects observed on terpenes 1 and 7 were higher when compared with cisplatin, used as positive control, with the exception of Jurkat cell line.

CONCLUSION

The efficiency of such an alternative extraction method led to the principal and abundant active component, 1, of I. coccinea, thus representing a considerable contribution for promising triterpenoid in cancer chemotherapy.

SUMMARY

The ultrasound-assisted extraction of Ixora coccinea flowers improved of the ursolic acid isolationMethanolic extract from flowers of I. coccinea provided, by ultrasound irradiation, after KOH-impregnated silica in chromatography column, the ursolic acid in 35% yieldThe ursolic acid and four derivatives were prepared and assayed against two lung cancer and four leukaemia cell linesThe ursolic acid and their 3-oxo-derivative, in general, were more cytotoxic when compared to cisplatin, used as positive control Abbreviations used: MTT: 3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, RP: reverse phase, TLC: thin layer chromatography, KOH: potassium hydroxide, IR: infrared, DMF: dimethylformamide, DMSO: dimethyl sulfoxide, TEA: triethylamine, RT: room temperature, EtOAc: ethyl acetate, MeOH: methanol, i-PrOH: iso-propanol, NMR: nuclear magnetic resonance, MDR: multiple drug resistance, RPMI: Roswell Park Memorial Institute.

Inhibition of phagocytic and intracellular killing activity of human neutrophils by aqueous and methanolic leaf extracts of Ixora coccinea

ETHNOPHARMACOLOGICAL RELEVANCE

Ixora coccinea is widely used in Ayurveda and traditional medicinal practices in Sri Lanka and in Asia for acute bronchitis, reddened eyes and eruptions and dermatological disorders. The aim of this study was to determine the underling mechanism of anti-inflammatory activity of Ixora coccinea with respect to its inhibitory activity on human neutrophils.

MATERIALS AND METHODS

Freeze-dried products of aqueous and methanolic leaf extracts (ALE and MLE) prepared from mature fresh leaves of Ixora coccinea and total human leukocytes purified by Dextran sedimentation were used in this study. Three in vitro functional assays were developed and used to assess the inhibitory effects of ALE and MLE on human neutrophils, (i) assay for change-in-shape (CIS) for inhibitory effects on neutrophil polarization, (ii) yeast phagocytosis assay to investigate phagocytic activity of neutrophils and (iii) an optimized quantitative NBT assay to detect the production of reactive oxygen species (ROS).

RESULTS

Both ALE and MLE demonstrated maximum inhibition at 500 µg/ml for CIS (75% and 79% respectively; IC₅₀ values 44.5 and 24.0 µg/ml respectively), yeast phagocytosis (100%; IC₅₀ values 18.0 and 30.0 µg/ml respectively) and ROS production (47% and 67% respectively; IC₅₀ values 248 and 360 µg/ml respectively). All three inhibitory effects of both ALE and MLE were dose-dependent (P<0.05).

CONCLUSION

This study has shown that both ALE and MLE of Ixora coccinea exhibit potent anti-neutrophil activity that inhibits its intracellular killing which was demonstrated by the significant inhibition of neutrophil activation, phagocytosis, and production of ROS. MLE showed more potent anti-neutrophil activity compared to ALE reflecting a higher anti-inflammatory activity.

Hepatoprotective effects of Ixora parviflora extract against exhaustive exercise-induced oxidative stress in mice

Ixora parviflora, a species of the Rubiaceae, is rich in polyphenols and flavonoids, and has been traditionally used as a folk medicine. An I. parviflora extract (IPE) has great antioxidant activity in vitro, including a scavenging effect on superoxide radicals, reducing power, and ferrous ion-chelating ability. However, whether IPE is efficacious against oxidative damage in vivo is not known. The purpose of this study was to determine the protective effects of IPE treatment on hepatic oxidative stress and antioxidant defenses after exhaustive exercise in mice. Fifty male C57BL/6 mice (6 week old) were randomly divided into five groups and designated a sedentary control with vehicle (C), and exhaustive exercise with vehicle (IPE0), low dosage (IPE10), medium dosage (IPE50) and high dosage (IPE100) of IPE at 0, 10, 50, and 100 mg/kg, respectively. After a single bout of exhaustive swimming exercise challenge, levels of blood ammonia and creatine kinase (CK), and hepatic superoxide dismutase (SOD) protein expression, thiobarbituric acid-reactive substance (TBARS), and gp91^phox, p22^phox, and p47^phox subunits of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expressions in the IPE0 group were significantly affected compared to those of the C group, but they were all significantly inhibited by the IPE treatments. Results of the present in vivo study in mice indicate that I. parviflora extract possesses antioxidative and hepatoprotective potential following exhaustive exercise.

Can scientific evidence support using Bangladeshi traditional medicinal plants in the treatment of diarrhoea? A review on seven plants

Diarrhoea is a common disease which causes pain and may be deadly, especially in developing countries. In Bangladesh, diarrhoeal diseases affect thousands of people every year, and children are especially vulnerable. Bacterial toxins or viral infections are the most common cause of the disease. The diarrhoea outbreaks are often associated with flood affected areas with contaminated drinking water and an increased risk of spreading the water-borne disease. Not surprisingly, plants found in the near surroundings have been taken into use by the local community as medicine to treat diarrhoeal symptoms. These plants are cheaper and more easily available than conventional medicine. Our question is: What is the level of documentation supporting the use of these plants against diarrhoea and is their consumption safe? Do any of these plants have potential for further exploration? In this review, we have choosen seven plant species that are used in the treatment of diarrhoea; Diospyros peregrina, Heritiera littoralis, Ixora coccinea, Pongamia pinnata, Rhizophora mucronata, Xylocarpus granatum, and Xylocarpus moluccensis. Appearance and geographical distribution, traditional uses, chemical composition, and biological studies related to antidiarrhoeal activity will be presented. This review reveals that there is limited scientific evidence supporting the traditional use of these plants. Most promising are the barks from D. peregrina, X. granatum and X. moluccensis which contain tannins and have shown promising results in antidiarrhoeal mice models. The leaves of P. pinnata also show potential. We suggest these plants should be exploited further as possible traditional herbal remedies against diarrhoea including studies on efficacy, optimal dosage and safety.