Investigation of Factors Affecting Extraction of Calophyllum inophyllum Seed Oil via Response Surface Methodology.

This study used the Soxhlet apparatus to investigate honne oil (HO) extraction optimization. Twenty-four (24) experiments were formulated using the D-optimal design considering extraction time (2 - 6 h), honne weight (20 - 60 g), and particle size using acetone. The yield, functional groups, physical and chemical properties, and fatty acid composition of the HO were assessed. The optimal extraction conditions established were a time of 6 h, fine particle size, and honne weight of 20 g with a high HO yield of 70.85 wt.%. The HO had an acid value and kinematic viscosity of 35.68 mg KOH/g oil and 52.96 mm 2 /s, respectively. The observed coefficient of determination of 0.9870 suggests that the model developed for the process is efficient. The functional groups and fatty acids of the HO confirm that it is highly unsaturated with the regions of trans-unsaturation bending vibrations and double bond stretching. The properties of the HO demonstrate that it could be used to produce biodiesel, notwithstanding the necessity for pretreatment.

A new chromanone acid derivative from the nut oil resin of Calophyllum inophyllum.

One novel chromanone acid derivative, namely inocalophylline C (1), together with one known compound calophyllolide (2), were isolated from the methanolic extract of nut oil resin of Calophyllum inophyllum L., a medicinal plant widely distributed in Vietnam. The isolated compound structures were elucidated by spectroscopic methods and the absolute configuration of 1 was established by the single-crystal X-ray crystallography as ethyl (R) 3-((2 R,3R,6R)-4-hydroxy-2,3-dimethyl-6-((R)-5-methyl-2-(prop-1-en-2-yl)hex-4-en-1-yl)-6-(3-methylbut-2-en-1-yl)-5,7-dioxo-3,5,6,7-tetrahydro-2H-chromen-8-yl)-3-phenylpropanoate.

Optimisation of Calophyllum inophyllum seed oil nanoemulsion as a potential wound healing agent.

BACKGROUND: Efficient delivery systems of Calophyllum inophyllum seed oil (CSO) in the form of nanoemulsion were optimised to enhance its stability and ensure its therapeutic efficiency as a potential agent for various biomedical applications. METHOD: Response Surface Methodology (RSM) was used to determine the effects of independent variables (oil, surfactant, water percentage and homogenisation time) on physicochemical characteristics, including droplet size, polydispersity index and turbidity. RESULTS: The optimised CSO nanoemulsion (CSONE) has a 46.68 nm particle size, 0.15 Polydispersity index value and 1.16 turbidity. After 4 weeks of storage at 5 ± 1 °C and 25 ± 1 °C, the CSONE was physically stable. The optimised CSO nanoemulsion showed enhancement in cell viability and wound healing in baby hamster kidney a clone BHK-21 (BSR) cells as compared to the CSO. The wound healing property of CSONE was higher than CSO. CONCLUSION: Thus, our in vitro wound healing results demonstrated that CSO in the nanoemulsion form can promote wound healing by enhancing the proliferation and migration of epidermal cells. The coarse emulsion of Calophyllum inophyllum seed oil nano emulsion was prepared using high shear homogeniser techniques. The optimised CSONE with the droplet size of 46.68 nm was prepared from a mixture of CSO, Tween 80, and high pure water (HPW), then used for the biological investigation. The in vitro cell monolayer scratch assay revealed that CSONE in the lowest concentration of CSO resulted in 100% wound closure after 48 hrs. The optimised CSO nanoemulsion was found to be a promising and effective approach in the treatment of wounds by boosting the proliferation and migration of epidermal cells.

Calofolic Acid-A from Calophyllum scriblitifolium Bark Has Vasorelaxant Activity via Indirect PKA Activation Caused by PI-3 Kinase Inhibition in Rat Vascular Smooth Muscle Cells.

Previously, we isolated 2R,3S,15R-calofolic acids (CAs) from Calophyllum scriblitifolium bark, which showed vasorelaxant activity on phenylephrine (PE)-precontracted rat aortic rings. Although the effect was suggested to be induced via an extracellular Ca2+-independent manner and mainly acts on vascular smooth muscle, the exact mechanism of action of CAs remained unclear. Thus, this study investigated the detailed mechanism of calofolic acid-A (CA-A) induced vasorelaxation in an aortic ring specimen using rat vascular smooth muscle cells (VSMCs). The levels of PE-induced phosphorylation on MLC Ser19 decreased in VSMCs pretreated with CA-A. CA-A also decreased the phosphorylation of MYPT1 Thr696 and MYPT1 Thr853. On the other hand, CA-A increased the PE-induced phosphorylation of MYPT1 Ser695 and MYPT1 Ser668, which are reported to be phosphorylated by a cAMP-dependent protein kinase (PKA). CA-A slightly increased PKA substrate phosphorylation in a concentration-dependent manner. Furthermore, CA-A enhanced isoproterenol (ISO)-induced cAMP accumulation and PKA substrate phosphorylation. Treatment with PI-3 kinase (PI3K) inhibitor, LY294002, enhanced ISO-induced cAMP accumulation and PKA substrate phosphorylation in the same manner as CA-A treatment. Furthermore, CA-A was found to directly inhibit PI3K enzyme activity in a dose-dependent manner. Taken together, the present study indicated that CA-A induces vasorelaxation through an indirectly activated PKA-MYPT1 pathway caused by inhibition of PI3K activity.

Two new xanthones from the root of Thai Calophyllum inophyllum and their toxicity against colon and liver cancer cells.

Two new xanthones, 1,3,6,7-tetrahydroxy-5-methoxy-4-(1',1'-dimethyl-2'-propenyl)-8-(3″,3″-dimethyl-2″-propenyl)-xanthone (1) and (2'S)-7-hydroxy caloxanthone B (2), were isolated from the root of Thai Calophyllum inophyllum Linn., together with twelve known xanthones (3-14). The structures of new compounds were elucidated based on spectroscopic data. In addition, compounds 4, 6 and 8 were isolated from the genus Calophyllum for the first time. The isolated compounds were evaluated for their cytotoxic activity against colon HCT-116 and liver Hep-G2 cancer cells. Among tested compounds, xanthones 5 and 14 possessing a prenyl moiety and a pyranyl ring fused at C-2 and C-3 displayed the most potent and selective cytotoxicity against HCT-116 colon cancers with the same IC50 values of 3.04 µM.

Calotetrapterins A-C, three new pyranoxanthones and their cytotoxicity from the stem bark of Calophyllum tetrapterum Miq.

Three new pyranoxanthones, calotetrapterins A-C (1-3) were isolated from the stem bark of Calophyllum tetrapterum Miq along with three known xanthones, α-mangostin (4), garciniafuran (5), and pyranojacareubin (6). All structures were elucidated based on their IR, UV, HRESIMS, 1 D (1H, 13C) and 2 D (HMBC, HMQC) NMR spectral data. Compounds 1-6 were tested to P-388 cells for cytotoxic activity, compound 2 exhibited high activity with IC50 value 1.0 µM.

A new xanthone dimer and cytotoxicity from the stem bark of Calophyllum canum.

A phytochemical investigation of the stem bark of Calophyllum canum resulted in the isolation of a new xanthone dimer identified as biscaloxanthone (1), together with four compounds; trapezifoliaxanthone (2), trapezifolixanthone A (3), taraxerone (4) and taraxerol (5). The structures of these compounds were determined via spectroscopic methods of IR, UV, MS and NMR (1D and 2D). The cytotoxicity of compounds 1-3 were screened against A549, MCF-7, C33A and 3T3L1 cell lines, wherein weak cytotoxic activities were observed (IC50 > 50 µm).

Structure-activity relationship of natural and synthetic coumarin derivatives against Mycobacterium tuberculosis.

Aim: Eight coumarin derivatives (1a-h) obtained from natural (-)-mammea A/BB (1) and 13 synthetic coumarins (2-14) had their cytotoxicity and biological activity evaluated against Mycobacterium tuberculosis H37Rv reference strain and multidrug-resistant clinical isolates. Materials & methods: Anti-M. tuberculosis activity was evaluated by resazurin microtiter assay plate, and the cytotoxicity of natural and synthetic products using J774A.1 macrophages by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Results: Compounds 1g, 5, 6, 12 and 14 were more active against M. tuberculosis H37Rv and multidrug-resistant clinical isolates with MIC values ranging from 15.6 to 62.5 µg/ml. Conclusion: These results demonstrate that the coumarin derivatives were active against multidrug-resistant clinical isolates, becoming potential candidates to be used in the treatment of resistant tuberculosis.

Report: Cytotoxic activity of phytochemicals from the stem bark of Calophyllum castaneum.

Phytochemical investigation on the dichloromethane stem bark extract of Calophyllum castaneum resulted in the isolation of five compounds, namely isoblancoic acid (1), blancoic acid (2), euxanthone (3), friedelin (4) and friedelinol (5). All these compounds were isolated for the first time from this plant. Their chemical structures were elucidated based on the spectroscopic analyses. The cytotoxicity of compounds 1-5 was assessed on a panel of cancer cell lines including bone (Saos-2, mg63), colorectal (HT29, Caco-2, HCC2998, SW48, HCT116, KM12), liver (HepG2), lung (H1299, Calu-3), and brain (C6), using 5-fluorouracil as positive control. Pronounced antiproliferative activities were observed for compound 1 which exhibited a comparable activity with the positive control, against brain (C6) and colorectal (SW48, KM12, HCT116) cancer cell lines showing IC50 values in the range of 14 to 65µM. Meanwhile, compound 5 displayed a greater cytotoxic effect showing at least 2-fold more strongly than the positive control, against C6 brain cancer cells. The assay findings have unveiled the therapeutic value of phytochemicals from Calophyllum castaneum as anti-cancer agents.

Cytotoxic xanthones isolated from Calophyllum depressinervosum and Calophyllum buxifolium with antioxidant and cytotoxic activities.

The stem bark of Calophyllum depressinervosum and Calophyllum buxifolium were extracted and examined for their antioxidant activities, together with cytotoxicity towards human cancer cells. The methanol extract of C. depressinervosum exhibited good DPPH and NO scavenging effects. The strongest BCB inhibition and FIC effects were shown by dichloromethane and ethyl acetate extracts of both species. Overall, DPPH, FRAP and FIC assays showed strong correlation with TPC. For cytotoxicity, hexane extract of C. depressinervosum possessed the strongest anti-proliferative activities towards SNU-1 cells while the hexane extract of C. buxifolium showed the strongest activity towards LS-174T and K562 cells with the IC50 values ranging from 7 to 17 µg/mL. The purification of plant extracts afforded eight xanthones, ananixanthone (1), caloxanthone B (2), caloxanthone I (3), caloxanthone J (4) xanthochymone B (5), thwaitesixanthone (6), 1,3,5,6-tetrahydroxyxanthone (7) and dombakinaxanthone (8). All the xanthones, except 1 were reported for the first time from both Calophyllum species. The xanthones were examined for their cytotoxic effect against K562 leukemic cells. Compounds 1 and 2 showed strong cytotoxicity with the IC50 values of 2.96 and 1.23 µg/mL, respectively. The molecular binding interaction of 2 was further investigated by performing molecular docking study with promising protein receptor Src kinase.

Tamanu oil potentiated novel sericin emulgel of levocetirizine: repurposing for topical delivery against DNCB-induced atopic dermatitis, QbD based development and in vivo evaluation.

The present study was aimed at preparing and evaluating levocetirizine (LCZD) loaded emulgel containing tamanu oil and sericin for atopic dermatitis (AD) therapy. The emulgel envisaged topical delivery of LCZD utilising natural antioxidants for superior therapeutic outcomes when compared with other conventional therapy. Tamanu oil based microemulsion (ME) was optimised utilising Box-Behnken design (BBD). The OPT-ME displayed globule size 379.5 ± 2.33 nm, polydispersity index 0.284, drug loading 0.41 ± 0.01% w/w, entrapment efficiency 94.34 ± 2.11% w/w and drug release 86.24 ± 4.90% respectively over a period of 24 h. The optimised formulation (OPT-ME) was further incorporated into sericin gel to form emulgel (LSE). In vivo pharmacodynamic studies revealed enhanced therapeutic potential of emulgel in terms of reduced scratching frequency and erythema score when compared with conventional gel. The superior therapeutic potential was further witnessed through histopathological and biochemical studies. The emulgel can be an alternative appropriate dosage form for the treatment of AD.

Chemical constituents from Vietnamese mangrove Calophyllum inophyllum and their anti-inflammatory effects.

In a search for anti-inflammatory activity in resources from Vietnamese mangroves, we found that a methanolic extract from the leaves of Calophyllum inophyllum (CIL) showed significant anti-inflammatory effects in vitro. Using various chromatographic techniques, we subsequently isolated 12 compounds (1-12) from a methanolic extract of CIL, including two novel compounds (1-2). The inhibitory effects of these compounds on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells were also evaluated. Compound 1 significantly suppressed NO production (IC50 = 2.44 ±â€¯0.88 µM), the secretion of pro-inflammatory cytokines (including interleukin-1 beta and tumor necrosis factor alpha), and the expression of inducible nitric oxide synthase through downregulation of nuclear factor-kappa-B signaling cascades. These results suggest that C. inophyllum leaves might be a useful resource for the development of drugs for the treatment of inflammation.

Calaxanthones A-C, three new xanthones from the roots of Calophyllum calaba and the cytotoxicity.

Three new xanthones, named calaxanthones A-C (1-3), along with 17 known xanthones (4-20) were isolated from the roots of Calophyllum calaba. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against five cancer cell lines (KB, HeLa S-3, HT-29, MCF-7 and HepG-2). Compound 3 showed potent cytotoxicity against all the five cancer cell lines with IC50 values in the range of 0.82-5.04 µM. Furthermore, compound 6 showed potent cytotoxicity against KB, HeLa S-3 and HepG2 cells with IC50 values of 7.06, 5.27 and 9.64 µM, respectively. Additionally, compound 7 showed potent cytotoxicity against KB cell with an IC50 value of 4.62 µM.

Network Pharmacology Uncovers Anticancer Activity of Mammea-Type Coumarins from Calophyllum brasiliense.

Mammea-type coumarins are a particular type of secondary metabolites biosynthesized by the tropical rainforest tree Calophyllum Brasiliense, which is distributed from South America to Mexico. Particularly, mammea A/BA and A/BB (alone or as a mixture) possess biological properties such as cytotoxic and antitumoral activities, however, most of its molecular targets remain unknown. In this context, novel bioinformatic approaches, such as network pharmacology analysis, have been successfully used in herbal medicine to accelerate research in this field, and the support of experimental validations has been shown to be quite robust. In the present study, we performed a network pharmacology analysis to assess the possible molecular biological networks that interact with mammea A/BA and A/BB. Moreover, we validated the most relevant networks experimentally in vitro on K562 cancer cells. The results of the network pharmacology analysis indicate that mammea A/BA and A/BB interacts with cell death, PI3K/AKT, MAPK, Ras, and cancer pathways. The in vitro model shows that mammea A/BA and A/BB induce apoptosis through the overexpression of the proapoptotic proteins Bax and Bak, disrupt the autophagic flux as seen by the cytosolic accumulation of LC3-II and p62, disrupting the mitochondria ultrastructure and concomitantly increase the intracellular calcium concentration. Additionally, docking analysis predicted a possible interaction with a rapamycin-binding domain of mTOR. In conclusion, we validated network pharmacology analysis and report, for the first time, that mammea A/BA and A/BB coumarins induce apoptosis through the inhibition of the autophagic flux, possibly interacting with mTOR.

Experimental study of methyl tert-butyl ether as an oxygenated additive in diesel and Calophyllum inophyllum methyl ester blended fuel in CI engine.

This work presents the effect of the ternary oxygenated additive on diesel biodiesel blended fuel to evaluate the engine characteristics. The Calophyllum inophyllum trees being abundant in India can lessen the dependence on petroleum imports to a specific extent. Methyl tertiary butyl ether is used as an oxygenated additive for the ternary blends preparation as 5-20% by volume. Seven blends of neat baseline diesel, biodiesel (Calophyllum inophyllum Methyl Ester), a blend of diesel (50%)-biodiesel (50%), a blend of diesel (50%)-biodiesel-methyl tert-butyl ether (5, 10, 15, and 20%) are prepared which are tested on a single cylinder, constant speed diesel engine. The experimental results were revealed that the replacement of biodiesel by MTBE has shown a slight reduction in brake thermal efficiency with a slight increase in brake-specific fuel consumption. Further, the MTBE addition in ternary blends reduced the unburned hydrocarbon, CO, and NOx by 63.9, 6.4, and 3.37% respectively. In addition, the carbon dioxide emission is almost similar to diesel fuel at a higher addition of MTBE with diesel-biodiesel blend. In the combustion point of view, the addition of 5% MTBE resulted in 3.49 and 5.1% reduction of peak pressure and heat release rate are observed as compared to diesel fuel. Critical analysis in combustion aspects is also carried out and it is witnessed with prolonged ignition delay during MTBE addition with diesel-biodiesel blends.

Calophyllum brasiliense Modulates the Immune Response and Promotes Leishmania amazonensis Intracellular Death.

Calophyllum brasiliense is a plant from the Brazilian rain forests and has been used in folk medicine for the treatment of various diseases, including leishmaniasis. This infectious disease depends on the Leishmania sp. and the host immune response. C. brasiliense antileishmanial activity is well known, but the effects on immune response remain to be investigated. This study showed the leishmanicidal and immunomodulatory effects of a 30 µg/mL of hydroalcoholic extract of C. brasiliense in murine macrophages before and after Leishmania (Leishmania) amazonensis infection. The semiquantitative cytokine RNA expression was determined by RT-PCR and the anti-Leishmania activity was measured by infection index (IF). Hydroalcoholic extract of C. brasiliense reduced more than 95% of IF when used before and after Leishmania infection, with 3 and 24 h of treatment (p < 0.05). C. brasiliense inhibited or reduced significantly (p < 0.05) the TNF-α, IL-1ß, IL-18, and IL-10 mRNA expression. The antileishmanial and anti-inflammatory effects showed the potential of C. brasiliense as an alternative therapy for leishmaniasis and it must be investigated.

Studies on the effects of storage stability of bio-oil obtained from pyrolysis of Calophyllum inophyllum deoiled seed cake on the performance and emission characteristics of a direct-injection diesel engine.

The highly unbalanced nature of bio-oil composition poses a serious threat in terms of storage and utilization of bio-oil as a viable fuel in engines. So it becomes inevitable to study the variations in physicochemical properties of the bio-oil during storage to value its chemical instability, for designing stabilization methodologies. The present study aims to investigate the effects of storage stability of bio-oil extracted from pyrolyzing Calophyllum inophyllum (CI) deoiled seed cake on the engine operating characteristics. The bio-oil is produced in a fixed bed reactor at 500 °C under the constant heating rate of 30 °C/min. All the stability analysis methods involve an accelerated aging procedure based on standards established by ASTM (D5304 and E2009) and European standard (EN 14112). Gas chromatography-mass spectrometry was employed to analytically characterize the unaged and aged bio-oil samples. The results clearly depict that stabilizing Calophyllum inophyllum bio-oil with 10% (w/w) methanol improved its stability than that of the unstabilized sample thereby reducing the aging rate of bio-oil to 0.04 and 0.13 cst/h for thermal and oxidative aging respectively. Engine testing of the bio-oil sample revealed that aged bio-oil samples deteriorated engine performance and increased emission levels at the exhaust. The oxidatively aged sample showed the lowest BTE (24.41%), the highest BSEC (20.14 MJ/kWh), CO (1.51%), HC (132 ppm), NOx (1098 ppm) and smoke opacity (34.8%).

Production and optimization of polyhydroxyalkanoates from non-edible Calophyllum inophyllum oil using Cupriavidus necator.

Polyhydroxyalkanoates (PHA) are biodegradable polymers found in the cellular masses of a wide range of bacterial species and the demand for PHA is steadily growing. In this work we have produced PHA from a low-cost substrate, Calophyllum inophyllum oil, using Cupriavidus necator. Effects of various process parameters such as Oil concentration, Nitrogen source and inoculum size on the production of PHA were studied using Response Surface Methodology. A quadratic equation was used in the model to fit the experimental data. It was found that the model could satisfactorily predict the PHA yield (R2=99.17%). Linear, quadratic and interaction terms used in the model were found to be statistically significant. Maximum PHA yield of 10.6gL-1 was obtained under the optimized conditions of oil concentration - 17.5%, inoculum concentration - 50mL/L and nitrogen content - 1.125gL-1, respectively. The product obtained was characterized using FTIR and NMR to confirm that it was PHA. The results demonstrate that C. inophyllum oil, a non-edible oil, can be potentially used as a low-cost substrate for the production of PHA.

Caloinophyllin A, a new chromanone derivative from Calophyllum inophyllum roots.

A new chromanone derivative, namely caloinophyllin A (1), along with eight known compounds (2-9), nobiletin (2), pentamethylquercetin (3), 3,5,7,4'-tetramethoxyflavone (4), 5,7,4'-trimethoxyflavone (5), 1,5-dihydroxyxanthone (6), 1,8-dimethoxy-2-hydroxyxanthone (7), 1,6-dihydroxy-7-methoxyxanthone (8) and 4-methoxycaffeic acid (9) were isolated from the roots of Calophyllum inophyllum. The structures of all the isolated compounds (1-9) were fully characterised using spectroscopic data, as well as comparison with the previous literature data. In addition, the quantum chemical calculation has been used to confirm the conformation of 1. Moreover, all isolated compounds were assessed for their in vitro cytotoxicity against five human cancer cell lines.

Airlanggins A-B, two new isoprenylated benzofuran-3-ones from the stem bark of Calophyllum soulattri.

Two new isoprenylated benzofuran 3-ones, airlanggin A (1) and B (2) along with two known xanthones, ananixanthone (3) and trapezifolixanthone (4) were isolated from the stem bark of Calophyllum soulattri. Structures of all the compounds were elucidated using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1-4 were evaluated for their cytotoxicity against P-388 cells, showing that compound 3 was the most active with IC50 0.68 µg/mL and compound 1 showed moderate activity with IC50 5.80 µg/mL.