Mangosteen (Garcinia mangostana L.) is a tropical evergreen tree that produces one of the most prized tropical fruits, commonly known as the "Queen of the Fruits.″ Mangosteen has the potential to occupy a rapidly expanding niche market in Hawaii. In October 2009, a disease was observed that produced brown leaf spots and blotches surrounded by bright yellow halos at a mangosteen orchard located in Hakalau, Hawaii (19° 53' 49″ N, 155° 7' 35″ W). Recently transplanted 10+ year old trees were 95 to 100% infected. Pieces of infected leaves and stems were surface-sterilized, plated on potato dextrose agar (PDA), and incubated at 24°C ± 1°C for 21 days. The fungus growing on PDA was pale buff with sparse aerial mycelium and acervuli containing black, slimy spore masses. Single spore isolates were used for the morphological characteristics and molecular analysis. Conidia were 5-celled. Apical and basal cells were hyaline; the three median cells were umber to olivaceous. Conidia (n = 50) were 24.3 ± 0.2 × 7.5 ± 0.1 μm, with apical appendages, typically three, averaging 24.3 ± 0.4 μm long, and a basal appendage averaging 6.7 ± 0.2 μm long. DNA sequences were obtained from the β-tubulin gene and the internal transcribed spacer (ITS1 and ITS2) and 5.8S regions of the rDNA to confirm the identification. The morphological descriptions and measurements were similar to P. virgatula (Kleb.) Steyaert (1). Although sequence data of the ITS region (GenBank Accession No. JN542546) supports the identity of the fungus as P. virgatula, the taxonomy of this genus remains confused since there are only a few type cultures, so it is impossible to use sequences in GenBank to reliably clarify species names (2). To confirm pathogenicity, six leaves of two 3-year-old seedlings were inoculated. Seven-day-old cultures grown on 10% V8 agar at 24°C under continuous fluorescent lighting were used for inoculations. The inoculum consisted of spore suspensions in sterile distilled water adjusted to 6 × 105 conidia/ml. Using a fine haired paint brush, the inoculum was brushed onto the youngest leaves, while sterile distilled water was used as the control. The plants were incubated in a clear plastic bag placed on the laboratory bench at 24°C for 48 hours, then placed on a greenhouse bench and observed weekly for symptoms. After 14 days, leaf spots ranging in size from pinpoint to 5.4 mm in diameter with a distinctive yellow halo were present. Within 35 days, the leaf spots enlarged to leaf blotches ranging in size from 11.5 × 13.3 mm up to 28.3 × 34.6 mm with brown centers and a distinctive yellow halo identical to the field symptoms. A Pestalotiopsis sp. identical to that used to inoculate the seedlings was recovered from the leaf spots and blotches, confirming Koch's postulates. The experiment was repeated twice. Pestalotiopsis leaf blight has been reported in other countries growing mangosteen, including Thailand, Malaysia, and North Queensland, Australia (3). However, to our knowledge, this is the first report of a Pestalotiopsis sp. causing a disease on mangosteen in Hawaii. Although this disease is considered a minor problem in the literature (3), effective management practices should be established to avoid potential production losses. References: (1) E. F. Guba. Monograph of Pestalotia and Monochaetia. Harvard University Press, Cambridge, MA. 1961. (2) S. S. N. Maharachchikumbura et al. Fungal Div. 50:167, 2011. (3) R. C. Ploetz. Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, Oxfordshire, UK, 2003.
Dry mangosteen leaves are one of the raw materials used to produce marker ink. However, research using this free and abundant resource is rather limited. The less efficient one-factor-at-a-time (OFAT) approach was mostly used in past studies on plant-based marker ink. The use of statistical analysis and the regression coefficient model (mathematical model) was considered essential in predicting the best combination of factors in formulating mangosteen leaf-based marker ink. Ideally, ink should have maximum color lightness, minimum viscosity, and fast-drying speed. The objective of this study to study the effect of glycerol and carboxymethyl cellulose (CMC) on the color lightness and viscosity of mangosteen-leaves-based marker ink. The viscosity, color lightness, and drying properties of the ink were tested, the significant effect of glycerol and CMC (responses) on ink properties was identified and the prediction model on the optimum value of the responses was developed by using response surface methodology (RSM). The microstructure of mangosteen leaves was analyzed to study the surface morphology and cell structure during dye extraction. A low amount of glycerol used was found to increase the value of color lightness. A decrease in CMC amounts resulted in low viscosity of marker ink. The optimum formulation for the ink can be achieved when the weight percents of glycerol, benzalkonium chloride, ferrous sulphate, and CMC are set at 5, 5, 1, and 3, respectively. SEM micrographs showed the greatest amount of cell wall structure collapse on samples boiled with the lowest amount of glycerol.
Skin aging is a complex natural process characterised by gradual diminishment of structural integrity and physiological imbalance of the skin tissue. Since the oxidative stress is tightly corelated to the skin aging process, the usage of antioxidant may serve as favourable strategies for slowing down the skin aging process. Mangosteen is an important fruit commodity and its extract had been extensively studied and revealing various biological activities. Present study aimed to assess the antioxidant and antiaging activity of mangosteen peel extract (MPE) and its phytochemical compounds. MPE and its compounds were subjected to ferric reducing antioxidant power (FRAP), hydroperoxide (H2O2) scavenging, anti-collagenase, anti-elastase, anti-hyaluronidase and anti-tyrosinase assay. MPE has the highest FRAP 116.31 ± 0.60 μM Fe(II) μg-1 extract, IC50 of MPE on H2O2 scavenging activity was 54.61 μg mL-1. MPE also has the highest anti elastase activity at IC50 7.40 μg mL-1. Alpha-mangostin showed potent anti-collagenase activity (IC50 9.75 μg mL-1). While gamma-mangostin showed potent anti-hyaluronidase (IC50 23.85 μg mL-1) and anti-tyrosinase (IC50 50.35 μg mL-1). MPE and its compounds were evaluated in vitro for antioxidant and antiaging activities. Current findings may provide scientific evidence for possible usage of mangosteen extract and its compounds as antioxidant and antiaging agent.
α-Mangostin was extracted from the pericarp of the Malaysian local Garcinia mangostana linn., The structure was characterised by Infrared red, UV-Visible and Nuclear Magnetic Resonance spectroscopic data. The fluorescence peak at 500nm in ethanol was not observed in PNIPAM microgel solution. The increase of colloidal size of the gel in the presence of α-mangostin was studied by Dynamic Light Scattering and Transmission Electron Microscope. The size of the particle also increases with increasing temperature up to 45⁰C after which it began to shrink. The TEM micrograph at 45°C showed a uniformly structured pattern of the gel occurs in the range of the lowest solution critical temperature.
Fruit ripening is a complex phenomenon involving a series of biochemical, physiological and organoleptic changes. Ripening process in mangosteen (Garcinia mangostana Linn.) is unique of which the fruit will only ripen properly if harvested during its middle stage (emergence of purple/pink colour) but not earlier (green stage). The knowledge on the molecular mechanism and regulation behind this phenomenon is still limited. Hence, electrospray ionization liquid chromatography mass spectrometry (ESI-LC-MS) based metabolomics analysis was applied to determine the metabolome of mangosteen ripening. Specifically, mangosteen pericarp, aril and seed were collected at four different ripening stages (stage 0: green, stage 2: yellowish with pink patches, stage 4: brownish red and stage 6: dark purple) and subjected to metabolite profiling analysis. The data provided in this article have been deposited to the EMBL-EBI MetaboLights database (DOI: 10.1093/nar/gks1004. PubMed PMID: 23109552) with the identifier MTBLS595. The complete dataset can be accessed here https://www.ebi.ac.uk/metabolights/MTBLS595.
Studies have suggested that sirtuin inhibition may have beneficial effects on several age-related diseases such as neurodegenerative disorders and cancer. Garcinia mangostana is a well-known tropical plant found mostly in South East Asia with several positive health effects. Some of its phytochemicals such as α-mangostin was found to be able to modulate sirtuin activity in mice and was implicated with inflammation, diabetes and obesity. However, comprehensive studies on sirtuin activity by the prenylated xanthones extracted from Garcinia mangostana have yet to be reported. The present study led to the discovery and identification of γ-mangostin as a potent and selective SIRT2 inhibitor. It was demonstrated that γ-mangostin was able to increase the α-tubulin acetylation in MDA-MD-231 and MCF-7 breast cancer cells. It was also found to possess potent antiproliferative activity against both cell lines. In addition, it was able to induce neurite outgrowth in the N2a cells.
Garcinia mangostana is a tropical fruit plant rich in antioxidant and bears recalcitrant seeds. The extent of water loss and low temperature tolerable by recalcitrant seed varies from regular orthodox seeds. Present study generates transcriptome resources for G. mangostana to postulate potential transcriptome differences between recalcitrant and orthodox seeds during seed germination process. Raw reads of pooled samples used for the assembly have been deposited in genbank accession SRR5412332.
Obesity is one of the pandemic chronic diseases commonly associated with health disorders such as heart attack, high blood pressure, diabetes or even cancer. Among the current natural products for obesity and weight control, Garcinia or more specifically hydroxycitric acid (HCA) extracted from Garcinia has been widely used. The evaluation of the potential toxicity of weight control supplement is of the utmost importance as it requires long term continuous consumption in order to maintain its effects. Majority of reports demonstrated the efficacy of Garcinia/HCA without any toxicity found. However, a few clinical toxicity reports on weight-loss diet supplements of which some were combinations that included Garcinia/HCA as an active ingredient showed potential toxicity towards spermatogenesis. Nonetheless, it cannot be concluded that Garcinia/HCA is unsafe. Those products which have been reported to possess adverse effects are either polyherbal or multi-component in nature. To date, there is no case study or report showing the direct adverse effect of HCA. The structure, mechanism of action, long history of the use of Garcinia/HCA and comprehensive scientific evidence had shown "no observed adverse effect level (NOAEL)" at levels up to 2800 mg/day, suggesting its safety for use.
The in vitro antitumour-promoting, cytotoxic, and antioxidant activities of two ester derivatives of garcinia acid, that is, 2-(butoxycarbonylmethyl)-3-butoxycarbonyl-2-hydroxy-3-propanolide (1) and 1',1''-dibutyl methyl hydroxycitrate (2), that had been previously isolated from the fruits of Garcinia atroviridis Griff. ex T. Anders (Guttiferae), were examined. Based on the inhibition of Epstein-Barr virus early antigen (EBV-EA) activation, compound 1 (IC(50): 70 μM) showed much higher (8-fold) antitumour-promoting activity than compound 2 (IC(50): 560 μM). In addition, both compounds were nontoxic towards CEM-SS (human T-lymphoblastic leukemia) cells (CD(50): >100 μM), Raji (human B-lymphoblastoid) cells (CD(50): >600 μM), and brine shrimp (LD(50): >300 μM). Although the antitumour-promoting activity of compound 1 is moderate compared with the known antitumour promoter genistein, its non-toxicity suggests the potential of compound 1 and related structures as chemopreventive agents. The weak antioxidant activity displayed by both compounds also suggested that the primary antitumour-promoting mechanism of compound 1 did not involve oxidative-stress quenching.
Garcinia species are reported to possess antimicrobial, anti-inflammatory, anticancer, anti-HIV and anti-Alzheimer's activities. This study aimed to investigate the in vitro cholinesterase enzyme inhibitory activities of garcihombronane C (1), garcihombronane F (2), garcihombronane I (3), garcihombronane N (4), friedelin (5), clerosterol (6), spinasterol glucoside (7) and 3β-hydroxy lup-12,20(29)-diene (8) isolated from Garcinia hombroniana, and to perform molecular docking simulation to get insight into the binding interactions of the ligands and enzymes. The cholinesterase inhibitory activities were evaluated using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. In this study, compound 4 displayed the highest concentration-dependent inhibition of both AChE and BChE. Docking studies exhibited that compound 4 binds through hydrogen bonds to amino acid residues of AChE and BChE. The calculated docking and binding energies also supported the in vitro inhibitory profiles of IC50. In conclusion, garcihombronanes C, F, I and N (1-4) exhibited dual and moderate inhibitory activities against AChE and BChE.
The effects of sucrose preculture duration and loading treatment on tolerance of Garcinia cowa shoot tips to cryopreservation using the PVS2 vitrification solution were investigated. Ultrastructural changes in meristematic cells at the end of the preculture and loading steps were followed in an attempt to understand the effects of these treatments on structural changes in cell membranes and organelles. Increasing preculture duration on 0.3 M sucrose medium from 0 to 3 days enhanced tolerance to PVS2 solution from 5.6 percent (no preculture) to 49.2 percent (3-day preculture). However, no survival was observed after cryopreservation. Examination of meristematic cells by transmission electron microscopy revealed the progressive accumulation of an electron-dense substance in line with increasing exposure durations to 0.3 M sucrose preculture. Treatment with a loading solution (2 M glycerol + 0.4 M sucrose) decreased tolerance of shoot tips to PVS2 vitrification solution and had a deleterious effect on the ultrastructure of G. cowa meristematic cells. This study suggests that G. cowa meristematic cells may lose their structural integrity due to exposure to glycerol present in the loading solution at a 2 M concentration, either due to its high osmotic potential, or due to its cytotoxicity.
Garcinia is commonly found in Malaysia, but limited information is available regarding endophytic fungi associated with this plant. In this study, 24 endophytic fungi were successfully recovered from different parts of two Garcinia species. Characterization of endophytic fungi was performed based on the conserved internal transcribed spacer (ITS) region sequence analysis and the antimicrobial properties. Results revealed that fruits of the plant appeared to be the highest inhabitation site (38 %) as compared with others. Glomerella sp., Guignardia sp., and Phomopsis sp. appeared to be the predominant endophytic fungi group in Garcinia mangostana and Garcinia parvifolia. Phylogenetic relationships of the isolated endophytic fungi were estimated from the sequences of the ITS region. On the other hand, antibacterial screening showed 11 of the isolates possessed positive response towards pathogenic and nonpathogenic bacteria. However, there was no direct association between certain antibacterial properties with the specific genus observed.
Our current interest in searching for natural anti-cancer lead compounds from plants has led us to the discovery that the stem and roots of Garcinia mangostana can be a source of such compounds. The stem furnished 2,8-dihydroxy-6-methoxy-5-(3-methylbut-2-enyl)-xanthone (1), which is a new xanthone. Meanwhile, the root bark of the plant furnished six xanthones, namely alpha-mangostin (2), beta-mangostin (3), gamma-mangostin (4), garcinone D (5), mangostanol (6), and gartanin (7). The hexane and chloroform extracts of the root bark of G. mangostana as well as the hexane extract of the stem bark were found to be active against the CEM-SS cell line. gamma-Mangostin (4) showed good activity with a very low IC(50) value of 4.7 microg/ml, while alpha-mangostin (2), mangostanol (6), and garcinone D (5) showed significant activities with IC(50) values of 5.5, 9.6, and 3.2 microg/ml, respectively. This is the first report on the cytotoxicity of the extracts of the stem and root bark of G. mangostana and of alpha-mangostin, mangostanol, and garcinone D against the CEM-SS cell line.
Studies on the stem of Garcinia mangostana have led to the isolation of one new xanthone mangosharin (1) (2,6-dihydroxy-8-methoxy-5-(3-methylbut-2-enyl)-xanthone) and six other prenylated xanthones, alpha-mangostin (2), beta-mangostin (3), garcinone D (4), 1,6-dihydroxy-3,7-dimethoxy-2-(3-methylbut-2-enyl)-xanthone (5), mangostanol (6) and 5,9-dihydroxy-8- methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2H,6H-pyrano-[3,2-b]-xanthene-6-one (7). The structures of these compounds were determined by spectroscopic methods such as 1H NMR, 13C NMR, mass spectrometry (MS) and by comparison with previous studies. All the crude extracts when screened for their larvicidal activities indicated very good toxicity against the larvae of Aedes aegypti. This article reports the isolation and identification of the above compounds as well as bioassay data for the crude extracts. These bioassay data have not been reported before.
A new xanthone, namely garcinexanthone G (1), along with eight known compounds, stigmasta-5,22-dien-3β-ol (2), stigmasta-5,22-dien-3-O-β-glucopyranoside (3), 3β-acetoxy-11α,12α-epoxyoleanan-28,13β-olide (4), 2,6-dimethoxy-p-benzoquinone (5), 1,3,5-trihydroxy-2-methoxyxanthone (6), 1,3,7-trihydroxyxanthone (7), kaempferol (8) and quercetin (9), were isolated from the stem bark of Garcinia atroviridis. Their structures were elucidated based on spectroscopic methods including nuclear magnetic resonance (NMR-1D and 2D), UV, IR, and mass spectrometry. All the isolated compounds were evaluated for their antioxidant properties based on the DPPH radical scavenging activities. Results showed that 1,3,7-trihydroxyxanthone and quercetin showed significant antioxidant activities with EC50 values of 16.20 and 12.68 μg/ml, respectively, as compared to the control, ascorbic acid (7.4 μg/ml).
Pancreatic cancer is an aggressive disease that progresses in a relatively symptom-free manner; thus, is difficult to detect and treat. Essential oil is reported to exhibit pharmacological properties, besides its common and well-known function as aromatherapy. Therefore, this study herein aimed to investigate the anti-proliferative effect of essential oil extracted from leaves of Garcinia atroviridis (EO-L) against PANC-1 human pancreatic cancer cell line. The cell growth inhibitory concentration at 50% (IC50) and selective index (SI) values of EO-L analyses were determined as 78 µg/mL and 1.23, respectively. Combination index (CI) analysis revealed moderate synergism (CI values of 0.36 to 0.75) between EO-L and 2 deoxy-d-glucose (2-DG) treatments. The treatments of PANC-1 cells with EO-L, 2-DG and EOL+2DG showed evidence of depolarization of mitochondrial membrane potential, cell growth arrest and apoptosis. The molecular mechanism causing the anti-proliferative effect between EO-L and 2-DG is potentially through pronounced up-regulation of P53 (4.40-fold), HIF1α (1.92-fold), HK2 (2.88-fold) and down-regulation of CYP3A5 (0.11-fold), as supported by quantitative mRNA expression analysis. Collectively, the current data suggest that the combination of two anti-proliferative agents, EO-L and 2-DG, can potentially be explored as therapeutic treatments and as potentiating agents to conventional therapy against human pancreatic cancer.
Phytochemical studies on the stem bark of Garcinia nervosa has resulted in the discovery of one new pyranoxanthone derivative, garner xanthone (1) and five other compounds, 1,5-dihydroxyxanthone (2), 6-deoxyisojacareubin (3), 12b-hydroxy-des-D-garcigerrin A (4) stigmasterol (5), and β-sitosterol (6). The structures of these compounds were elucidated with the aid of spectroscopic techniques, such as NMR and MS. The crude extracts of the plant were assessed for their antimicrobial activity.
Pure β-mangostin (1) was isolated from the stem bark of Garcinia mangostana L. One monoacetate (2) and five O-alkylated β-mangostin derivatives (3-7) were synthesised from β-mangostin. The structures of these compounds were elucidated and determined using spectroscopic techniques such as 1D NMR and MS. The cytotoxicities and anti-inflammatory activities of these five compounds against RAW cell 264.7 were tested. The structural-activity relationship studies indicated that β-mangostin showed a significant activity against the LPS-induced RAW cell 264.7, while the acetyl- as well as the O-alkyl- β-mangostin derivatives did not give good activity. Naturally occurring β-mangostin demonstrated comparatively better anti-inflammatory activity than its synthetic counterparts.
Since α-mangostin in mangosteen fruits was reported to be the main compound able to provide natural antioxidants, the microwave-assisted extraction process to obtain high-quality α-mangostin from mangosteen pericarp (Garcinia mangostana L.) was optimized using a central composite design and response surface methodology. The parameters examined included extraction time, microwave power, and solvent percentage. The antioxidant and antimicrobial activity of optimized and non-optimized extracts was evaluated. Ethyl acetate as a green solvent exhibited the highest concentration of α-mangostin, followed by dichloromethane, ethanol, and water. The highest α-mangostin concentration in mangosteen pericarp of 121.01 mg/g dry matter (DM) was predicted at 3.16 min, 189.20 W, and 72.40% (v/v). The verification of experimental results under these optimized conditions showed that the α-mangostin value for the mangosteen pericarp was 120.68 mg/g DM. The predicted models were successfully developed to extract α-mangostin from the mangosteen pericarp. No significant differences were observed between the predicted and the experimental α-mangostin values, indicating that the developed models are accurate. The analysis of the extracts for secondary metabolites showed that the total phenolic content (TPC) and total flavonoid content (TFC) increased significantly in the optimized extracts (OE) compared to the non-optimized extracts (NOE). Additionally, trans-ferulic acid and catechin were abundant among the compounds identified. In addition, the optimized extract of mangosteen pericarp with its higher α-mangostin and secondary metabolite concentrations exhibited higher antioxidant activities with half maximal inhibitory concentration (IC50) values of 20.64 µg/mL compared to those of the NOE (28.50 µg/mL). The OE exhibited the highest antibacterial activity, particularly against Gram-positive bacteria. In this study, the microwave-assisted extraction process of α-mangostin from mangosteen pericarp was successfully optimized, indicating the accuracy of the models developed, which will be usable in a larger-scale extraction process.