This study investigated the chemical composition and antimicrobial activity of propolis collected from two stingless bee species Tetragonula laeviceps and Tetrigona melanoleuca (Hymenoptera: Apidae). Six xanthones, one triterpene and one lignane were isolated from Tetragonula laeviceps propolis. Triterpenes were the main constituents in T. melanoleuca propolis. The ethanol extract and isolated compounds from T. laeviceps propolis showed a higher antibacterial activity than those of T. melanoleuca propolis as the constituent α-mangostin exhibited the strongest activity. Xanthones were found in propolis for the first time; Garcinia mangostana (Mangosteen) was the most probable plant source. In addition, this is the first report on the chemical composition and bioactivity of propolis from T. melanoleuca.
Dietary supplements (DS) are extensively consumed worldwide despite unproven efficacy. The true incidence of DS-induced liver injury (DSILI) is unknown but is probably under-diagnosed due to the general belief of safety of these products. Reported cases of herbals and DS-induced liver injury are increasing worldwide. The aim of this manuscript is to report a tabular listing with a description of DS associated with hepatotoxicity as well as review the phenotype and severity of DSILI. Natural remedies related to hepatotoxicity can be divided into herbal product-induced liver injury and DS-induced liver injury. In this article, we describe different DS associated with liver injury, some of them manufactured DS containing several ingredients (Herbalife™ products, Hydroxycut™, LipoKinetix™, UCP-1 and OxyELITE™) while others have a single ingredient (green tea extract, linoleic acid, usnic acid, 1,3-Dimethylamylamine, vitamin A, Garcinia cambogia and ma huang). Additional DS containing some of the aforementioned ingredients implicated in liver injury are also covered. We have also included illicit androgenic anabolic steroids for bodybuilding in this work, as they are frequently sold under the denomination of DS despite being conventional drugs.
Three new xanthones, garcinolic acid (1), 10α-ethoxy-9,10-dihydromorellic acid (2), and 10α-ethoxy-9,10-dihydrogambogenic acid (3), along with six known compounds were isolated from the resin of Garcinia hanburyi. These compounds were tested for their cytotoxicities against A549, HCT116, SK-BR-3 and HepG2, and showed high inhibitory effects on the cell lines.
Applications for antimicrobials derived from the mangosteen (Garcinia mangostana L.) plant are presently restricted by high production costs. Extraction from cultivation or processing waste streams using a solvent free approach could lessen to permit commercial applications in food processing and preservation.
Two new xanthones, designated garcimangosxanthone F (1) and garcimangosxanthone G (2), were isolated from the EtOAc-soluble fraction of ethanolic extract from the pericarp of Garcinia mangostana. Their structures were established as 1,6,7-trihydroxy-5-(3-methylbut-2-enyl)-8-(3-hydroxy-3-methylbutyl)-6',6'-dimethylpyrano[2',3':3,2]xanthone and 1,6,7-trihydroxy-5-(3-methylbut-2-enyl)-8-(3-hydroxy-3-methylbutyl)-6',6'-dimethyl-4',5'-dihydropyrano[2',3':3,2]xanthone, respectively, on the basis of their 1D, 2D NMR and MS data interpretation.
Two new xanthones: mangostanaxanthones I (3) and II (5) were isolated from the pericarp of Garcinia mangostana, along with four known xanthones: 9-hydroxycalabaxanthone (1), parvifolixanthone C (2), α-mangostin (4), and rubraxanthone (6). Their structures were elucidated on the basis of IR, UV, 1D, 2D NMR, and MS spectroscopic data, in addition to comparison with literature data. The isolated compounds were evaluated for their antioxidant, antimicrobial, and quorum-sensing inhibitory activities. Compounds 3 and 5 displayed promising antioxidant activity with IC50 12.07 and 14.12μM, respectively using DPPH assay. Compounds 4-6 had weak to moderate activity against E. coli and S. aureus, while demonstrated promising action against B. cereus with MICs 0.25, 1.0, and 1.0mg/mL, respectively. The tested compounds were inactive against C. albicans. However, they showed selective antifungal potential towards A. fumigatus. Compounds 3 and 4 possessed quorum-sensing inhibitory activity against Chromobacterium violaceum ATCC 12472.
Species of Garcinia have been used to combat malaria in traditional African and Asian medicines, including Ayurveda. In the current study, we have identified antiplasmodial benzophenone and xanthone compounds from edible Garcinia species by testing for in vitro inhibitory activity against Plasmodium falciparum. Whole fruits of Garcinia xanthochymus, G. mangostana, G. spicata, and G. livingstonei were extracted and tested for antiplasmodial activity. Garcinia xanthochymus was subjected to bioactivity-guided fractionation to identify active partitions. Purified benzophenones (1-9) and xanthones (10-18) were then screened in the plasmodial lactate dehydrogenase assay and tested for cytotoxicity against mammalian (Vero) cells. The benzophenones guttiferone E (4), isoxanthochymol (5), and guttiferone H (6), isolated from G. xanthochymus, and the xanthones α-mangostin (15), β-mangostin (16), and 3-isomangostin (17), known from G. mangostana, showed antiplasmodial activity with IC50 values in the range of 4.71-11.40 µM. Artemisinin and chloroquine were used as positive controls and exhibited IC50 values in the range of 0.01-0.24 µM. The identification of antiplasmodial benzophenone and xanthone compounds from G. xanthochymus and G. mangostana provides evidence for the antiplasmodial activity of Garcinia species and warrants further investigation of these fruits as dietary sources of chemopreventive compounds.
The mangosteen (Garcinia mangostana) is a tropical fruit native to Southeast Asia and has long been reported to contain multiple health promoting properties. This fruit is an abundant source of xanthones, a class of polyphenolic compounds with a distinctive tricyclic aromatic ring system and is largely responsible for its biological activities including anti-cancer activity. Herein we describe the anti-cancer activity and mechanisms of mangosteen polyphenolic xanthones including α-Mangostin against breast cancer and prostate cancer. So far, extracts and individual xanthones have been found to induce apoptosis and inhibit proliferation on cancer cells in vitro and in vivo. Based on the reported findings there is clear evidence that these polyphenols target multiple signaling pathways involved in cell cycle modulation and apoptosis. Further work is required to understand its potential for health promotion and potential drug discovery for prostate and breast cancer chemoprevention.
The fruit rind of Garcinia gummi-gutta, commonly known as Garcinia cambogia (syn.), is extensively used traditionally as a flavourant in fish curries due to its sharp sour taste. Additional ethnobotanical uses include its use as a digestive and a traditional remedy to treat bowel complaints, intestinal parasites and rheumatism. This small fruit, reminiscent of a pumpkin in appearance, is currently most popularly used and widely advertised as a weight-loss supplement. Studies have shown that the extracts as well as (-)-hydroxycitric acid (HCA), a main organic acid component of the fruit rind, exhibited anti-obesity activity including reduced food intake and body fat gain by regulating the serotonin levels related to satiety, increased fat oxidation and decreased de novo lipogenesis. HCA is a potent inhibitor of adenosine triphosphate-citrate lyase, a catalyst for the conversion process of citrate to acetyl-coenzyme A, which plays a key role in fatty acid, cholesterol and triglycerides syntheses. The crude extract or constituents from the plant also exerted hypolipidaemic, antidiabetic, anti-inflammatory, anticancer, anthelmintic, anticholinesterase and hepatoprotective activities in in vitro and in vivo models. Phytochemical studies of various plant parts revealed the presence of mainly xanthones (e.g. carbogiol) and benzophenones (e.g. garcinol) together with organic acids (e.g. HCA) and amino acids (e.g. gamma aminobutyric acid). Currently, a large number of G. cambogia/HCA dietary supplements for weight management are being sold although the possible toxicity associated with the regular use of these supplements has raised concerns. In most cases, complaints have been related to multicomponent formulations and at this stage G. cambogia has not been confirmed as the potentially toxic culprit. This review presents a scientific overview of G. cambogia with reference to relevant botanical aspects, ethnobotanical uses, phytochemistry and biological activity as well as toxicity.
Mangosteen (Garcinia mangostana L.) is a tropical tree native to Southeast Asia that produces a fruit whose pericarp contains a family of tricyclic isoprenylated polyphenols referred to as xanthones. Numerous in vitro studies have shown that these xanthones possess anti-oxidant, anti-proliferative, pro-apoptotic, anti-inflammatory and anti-carcinogenic activities. Aggressive marketing of such health promoting benefits has resulted in mangosteen’s classification as a “superfruit”. This has led to sales of mangosteen containing beverages in USA alone exceeding $200 million in 2008 despite very limited animal and human studies. This review will (a) critically address recent reports of in vivo studies on the bioavailability and metabolism of mangosteen xanthones, (b) update the in vitro and in vivo data on anti-cancer and anti-inflammatory activities of mangosteen xanthones, and © suggest needed areas of inquiry regarding the absorption, metabolism and efficacy of mangosteen xanthones.