Rhizomes Of Hedychium Coronarium Research Articles

Cosmeceutical Activities of Essential Oils from the Rhizomes of Plants in the Zingiberaceae Family

The plants in the Zingiberaceae family are often rhizomatous annual or perennial herbs with considerable economic value. This study aimed to investigate the cosmeceutical activities of essential oils from the rhizomes of Hedychium coronarium J. Koenig, Curcuma caesia Roxb., and Curcuma longa L. The essential oils were obtained from hydrodistillation and subjected to investigations of antioxidant activities by 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power, and ferric thiocyanate assay. Furthermore, the whitening properties were investigated in terms of anti-tyrosinase inhibition, whereas the anti-skin aging activities were investigated through collagenase, elastase, and hyaluronidase inhibition. The results showed that all essential oils exhibited low antioxidant, anti-elastase, and anti-collagenase activities. On the other hand, H. coronarium oil was the only essential oil in the present study, which was found to possess anti-tyrosinase activity, with the inhibition of 98.4 ± 5.5% and 30.2 ± 1.7% at the final concentration of 0.1 mg/ml, when the substrate were L-tyrosine and L-DOPA, respectively. Interestingly, it was highlighted that the anti-tyrosinase activity of H. coronarium oil was stronger than that of kojic acid, a well-known whitening agent, when the substrate was L-tyrosine. Besides, H. coronarium oil and C. longa oil exhibited promising anti-hyluronidase activities with inhibition of 83.6 ± 1.0% and 82.9 ± 2.2%, respectively, which were comparable to that of epigallocatechin gallate (100.0 ± 0.0%). All essential oil induced irritations in the HET-CAM test at the tested concentration of 5 mg/ml in 10% dimethyl sulfoxide in olive oil. Therefore, H. coronarium oil was suggested as an attractive ingredient in cosmeceutical products for whitening and anti-aging.

Diastereotopic labdane diterpenoids from rhizomes of Hedychium coronarium with α-glucosidase activity and their molecular docking study

Diastereotopic labdane diterpenoids from rhizomes of Hedychium coronarium with α-glucosidase activity and their molecular docking study

Proximate Analysis, Phytochemical Screening and High Resolution Liquid Chromatography Mass Spectrophotometry Analysis of Essential Oils of Hedychium Coronarium J. Koenig, a Medicinal and Aromatic Plant

Medicinal plants have been used in all cultures as a source of medicine since ages. When parts of plants such as rhizomes, leaves or barks and other natural materials are used as drugs to treat illnesses, they are called crude drugs and the study of crude drugs is called pharmacognosy. Proximate analysis in plants gives valuable information and help to assess the quality of a crude drug. Beneficial effects of crude drugs are believed to be attributed to plant phytochemicals. Hedychium coronarium J. Koenig, a medicinal and aromatic plant of high value is an endangered and red-listed plant. The rhizome of this plant is used for the treatment of various diseases. Crude extracts prepared from the rhizomes show antibacterial and antifungal properties. Essential oils obtained from Hedychium coronarium are found to be rich in terpenes and used for bactericidal, fungicidal, medicinal and cosmetic applications. The present study assesses the quality of crude drugs prepared from this highly medicinal plant. Proximate analysis and phytochemical screening of rhizomes of Hedychium coronarium, which is frequently consumed as food and as medicine were carried out. Ash content was found to be low) when compared to the moisture content. The water extractive value was more than alcohol extractive. Preliminary tests carried out on phytochemicals revealed the presence of terpenoids and oils. High Resolution Liquid Chromatography Mass Spectrophotometry was carried to ascertain the different components of essential oils and revealed the presence of eucalyptol (1,8-cineole), caryophyllene oxide, camphor, linoleic acid, ricinin, phloroglucinol, 6-gingerol, carvone and arjungenin.

Anticancer activity of micropropagated Hedychium coronarium rhizome essential oil

Cancer is a life threatening disease than any other diseases which is leading to death throughout the world. The natural products should be explored as anticancer agents which are not expensive, easily available and most beneficial to humans. Today the current research is being done on secondary metabolites and bioactive compounds present in the medicinal plants alongwith their therapeutic properties. Zingiberaceae family from centuries is used as spices and bears vast pharmacological activities including Hedychium coronarium. Also another most important characteristic of this family is the aromatic essential oil present in its leaves and rhizomes. In the present study, Hedychium coronarium rhizome essential oils were treated against human breast cancer cell line or MCF7 and human cervical cancer cell line or HeLa by MTT assay. For validation of the cytotoxic activity, MCF7 and HeLa cell were used against various concentrations of aromatic rhizome essential oil respectively. This study revealed that bioactive compound present in rhizome oil was most significantly active when tested against MCF7 and HeLa cell line.

Response of rhizomes of the invasive Hedychium coronarium J. König (Zingiberaceae) to different soil moisture conditions

The ability to maintain high competitiveness under a wide range of conditions is common among successful invasive species. The performance of rhizomatous macrophytes in different habitats is closely related to morphological and physiological adaptations in the rhizome system. We investigated the effects of soil moisture conditions on the microstructure of rhizomes of Hedychium coronarium (Zingiberaceae), an aggressive invader of Neotropical riparian sites. We collected rhizome fragments of H. coronarium and soil samples in wet and dry regions of riparian areas dominated by this species in southeastern Brazil. We measured soil moisture content gravimetrically and rhizome fragments were fixed, sectioned, and stained for histological analysis. Only rhizomes from wet regions exhibited aerenchyma, whereas amyloplasts were much more abundant and larger in rhizomes from dry regions than in rhizomes from wet regions. Even though low starch content in wet soils indicates the occurrence of anaerobic metabolism, the presence of aerenchyma may contribute to the typically high performance of H. coronarium in waterlogged soils. Although further studies are needed to assess how responses at the rhizome level affect the competitive ability of H. coronarium, our findings show that they may play a role in the dominance of this species in Neotropical riparian sites.

FORMULASI SEDIAAN SERBUK EFERVESEN DARI EKSTRAK ETANOL ANGKAK (Monascus purpureus) DENGAN METODE FOAM-MAT DRYING

Indonesia has various types of plants that have potential as medicine to overcome health problems in line with the expansion of the traditional medicine industry. One example of plants from the Zingiberaceae family is Hedychium coronarium, which is not widely known by the community despite it has efficacy as an antibacterial which is not inferior to other Zingiberaceae family. The research was conducted to determine whether the Hedychium coronarium rhizome shown to have antibacterial activity against the growth of Staphylococcus aureus and Escherichia coli, knowing antibacterial compound that contained in Hedychium coronarium rhizome, also knowing the most effective extraction method to take the antibacterial compound from Hedychium coronarium rhizome. The gandasuli rhizome was extracted by maceration and reflux with 96% ethanol. Antibacterial activity test carried out by the agar diffusion method, and the analysis of antibacterial compounds with bioautography, and the results are monitored with vanillin-sulfuric acid. Maceration and reflux extract at a concentration of 90% have antibacterial activity with inhibition zones, each for 8 and 10 mm against Escherichia coli as well as 9 and 10 mm against Staphylococcus aureus. Bioautography results show a positive effect on the appearance of vanillinsulfuric acid. Reflux extract has better antibacterial activity, while the antibacterial compound is an essential oil group.

Modulating effect of Coronarin D in 5-fluorouracil resistance human oral cancer cell lines induced apoptosis and cell cycle arrest through JNK1/2 signaling pathway

Coronarin D (CD) is one of the main components of Hedychium coronarium rhizome, which has therapeutic potential by reducing cell proliferation in cancer cells. However, the mechanism of CD to 5-fluorouracil (5FU) oral cancer cell remain unclearly. This study discusses the CD to 5FU chemoresistance oral squamous cell carcinoma (OSCC) biochemical mechanisms and possibly pathways to inhibit multiplication in oral cancer. The effect of CD-treated 5FU-chemoresistance human oral cancer cell lines were subjected to MTT assay, cell cycle assay, DAPI assay, annexin-V/PI double staining assay and mitochondrial membrane potential measurement. Furthermore, western blotting was performed to assess the effect of CD on the expression levels of apoptosis related protein and MAPK signaling pathway. The results of the study evidenced that CD reduced viability of 5FU cancer cells in a dose- and time-dependent manner compared with control. The cytotoxic effect of CD lead to cell cycle arrest in the G2/M phase and induced apoptosis in both internal and external pathways. CD induces apoptosis by enhancing phosphorylation of JNK, further exploring the combination of CD and SP600125 reduced the overexpression of phosphate JNK levels. The mechanism of action of CD in 5FU on human oral cancer cells is reported for the first time and can hopeful to be a potential therapeutic agent for 5FU against human oral cancer cells.

In Vitro and In Vivo Anti-diabetic Activity of Fractions Obtained from the Unexplored Hedychium coronarium Rhizome

Despite the availability of numerous medicines for diabetes treatment, compounds derived from plants are gaining popularity due to their lesser side effects. The present investigation was carried out to determine the anti-diabetic activity of a terpenoid-rich fraction obtained from the rhizomes of Hedychium coronarium under in vitro and in vivo. The authors performed in vitro assays to determine glucose uptake in insulin-resistant cell lines. Further, the effect of terpenoid fraction was tested using albino Wistar rats. The streptozotocin-induced diabetic rats were treated with different concentrations of most active fraction, and results were compared with the standard drug insulin. At regular intervals, the blood glucose level and the bodyweight of the rats were monitored. The serum, biochemical and histological parameters related to the liver and kidney were also estimated. The fraction at 10 mg/kg.b.wt. has shown a significant reduction in blood glucose level and an increase in bodyweight. This specific concentration increases the activity of antioxidant enzymes, but reduces the activity of carbohydrate-metabolizing enzymes leading to normal blood glucose level. The normal cellular architecture of liver and kidney tissue was also retained. The significant observations obtained from both in vitro and in vivo studies suggest the potential role of terpene-rich fraction obtained from H. coronarium rhizomes in the treatment of diabetes. It also inferred that the fraction controls diabetes by regulating various parameters associated with diabetes-related complications.

Antagonistic Endophytic Fungi of Hedychium coronarium J. Koenig from Hutan Sibayak and Taman Hutan Raya, North Sumatra against Staphylococcus aureus ATCC® 29213TM

Possible role of endophytic microbes has been receiving much attention from different aspects and all plants are believed to have an endophytic association. Some medicinal plants have been reported to harbor endophytic microbes capable of producing bioactive compounds. Endophytes may benefit plant host by secreting similar bioactive compounds leading to systemic plant defenses through synthesis of antimicrobial compounds. In this study, we reported that rhizome of Hedychium coronarium J. Koenig (a member of Zingiberaceae), native of Hutan Sibayak and Taman Hutan Raya, North Sumatra, is inhabited by various endophytic fungi morphotypes. Total of 28 fungal morphotypes were recovered from rhizome parts and differentiated based on morphological characters. Most fungal strains displayed antibacterial activities ranging from 0,00 (no activity) to 30 mm (very strong activity) against Staphylococcus aureus ATCC® 29213™. Based on this preliminary result, we may propose some antagonistic strains as candidates for further study regarding to the production of antibacterial compounds.

Chemical characterization and phytotoxicity of the essential oil from the invasive Hedychium coronarium on seeds of Brazilian riparian trees

The release of allelochemical compounds by some plants may directly affect the development of other plant species and is considered one of the mechanisms that facilitate plant invasions. However, little is known about the role phytotoxicity plays in plant invasions in the neotropics, especially regarding to the response of different native species to the phytotoxic compounds of invasive plants. In this study, we assessed the effect of oil extracted from the rhizomes of Hedychium coronarium J. König, an important invasive plant in Brazilian riparian habitats, on the germination speed index (GSI) and germination percentage (GP) of four tree species native from Brazilian riparian forests (Anadenanthera macrocarpa, Peltophorum dubium, Mimosa bimucronata and Sesbania virgata). We also measured the radicle growth of S. virgata. The essential oil was extracted, chemically characterized, and germination bioassays were performed using oil concentrations of 0.01%, 0.1% and 1%, distilled water and Tween 80 (1%) as controls. The concentration 1% of the essential oil inhibited the GP and the GSI of all tested species (except the GP of S. virgata) and the radicle growth of S. virgata. The oil concentration 0.1% also reduced the GSI and GP of M. bimucronata. Our results revealed that some phytotoxic compounds of the invasive H. coronarium negatively affect the germination of native tree species, which may enhance its dominance in riparian forests.

Effects of phosphorylation on the chemical composition, molecular structure, and paste properties of Hedychium coronarium starch

This work describes the chemical modification of a non-conventional starch by means of phosphorylation, improving its characteristics in order to meet the demands of the consumer market. The evaluation was made of the effect of phosphorylation on the chemical composition, molecular structure, and paste properties of starch extracted from rhizomes of Hedychium coronarium. Phosphorylation was performed using sodium tripolyphosphate (3–7%), with reaction times of 20, 30, and 40 min. Molecular structure, morphology, chemical composition, and physical properties of the modified starches were analyzed. Phosphorus was not detected in the native sample; however, phosphorylation generated distarch phosphates containing 0.013, 0.233, and 0.477% of phosphorus, with B-type crystallinity patterns, which were more stable than the native starch. The paste properties showed that phosphorylation had a strong influence on the viscosity of the starch reducing the tendency for retrogradation and increasing peak viscosity which was higher than that of native starch. The characteristics of modified H. coronarium starch by phosphorylation produced suitable starches for applications requiring stronger paste consistency and low retrogradation.

Chemical Composition and Biological Activity of Five Essential Oils from the Ecuadorian Amazon Rain Forest.

The chemical composition and biological activity of essential oils isolated from the leaves of Siparuna aspera, Siparuna macrotepala, Piper leticianum, Piper augustum and the rhizome of Hedychium coronarium were evaluated. These species are used medicinally in different ways by the Amazonian communities that live near the Kutukú mountain range. Chemical studies revealed that the main components for the two Siparuna species were germacrene D, bicyclogermacrene, α-pinene, δ-cadinene, δ-elemene, α-copaene and β-caryophyllene; for the two Piper species β-caryophyllene, germacrene D, α-(E,E)-farnesene, β-elemene, bicyclogermacrene, δ-cadinene and for H. coronarium 1,8-cineole, β-pinene, α-pinene and α-terpineol. The antioxidant activity of all essential oils was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), photochemiluminescence (PCL) quantitative assays, and DPPH and ABTS bioautographic profiles, with different results for each of them. Antimicrobial activity studies were carried out on three yeasts, six Gram positive and four Gram negative bacteria, by means of the disc diffusion method. The essential oil of H. coronarium showed the most relevant results on L. grayi, K. oxytoca and S. mutans, P. augustum and P. leticianum on S. mutans. An antibacterial bioautographic test for H. coronarium was also carried out and highlighted the potential activity of terpinen-4-ol and 1,8-cineole.

JNK Inactivation Induces Polyploidy and Drug-Resistance in Coronarin D-Treated Osteosarcoma Cells.

Inhibition of proliferating cells is a critical strategy for cancer therapy. In this study, we demonstrated that coronarin D, a natural component extracted from the rhizomes of Hedychium coronarium, significantly suppressed the proliferation of osteosarcoma cells. The treatment with coronarin D resulted in the activation of caspase-3 and apoptosis. This treatment induced the accumulation of cyclin B1 and DNA condensation indicating the treated osteosarcoma cells were arrested in mitotic phase. Furthermore, the treatment with coronarin D increased the levels of phosphorylated c-Jun NH2-terminal kinase (JNK) in human osteosarcoma cells. Pretreatment with JNK inhibitor blocked the accumulation of cyclin B1 and DNA condensation, resulting the accumulation of tetraploid cells in coronarin D-treated osteosarcoma HOS cells, indicating JNK inactivation blocked the mitotic entry and arrested cells in the 4 N state. After adaptation, the arrested tetraploid cells continued to duplicate their DNA resulting in polyploidy. Interestingly, when the arrested mitotic cells induced by coronarin D were treated with JNK inhibitor, the accumulated cyclin B1 and DNA condensation were immediately eliminated. These arrested 4 N cells loss the ability to undergo cytokinesis, and ultimately continued to duplicate DNA upon prolonged arrest resulting in the production of polyploid populations. JNK inactivation, either by the pretreatment with JNK inhibitor or the treatment with JNK inhibitor in coronarin D-induced mitotic cells, both caused resistance to coronarin D-induced cell death. Taken together, our findings indicate that coronarin D induces the apoptosis and mitosis arrest in human osteosarcoma cells. JNK has a crucial role in coronarin D-induced mitosis arrest and apoptosis. We hypothesize that functional evaluation of JNK may produce more specific and effective therapies in coronarin D-related trail for treatment of human osteosarcoma.

UJI ANTIBAKTERI RIMPANG GANDASULI (HEDYCHIUM CORONARIUM) TERHADAP BAKTERI STAPHYLOCOCCUS AUREUS DAN ESCHERICHIA COLI DENGAN PERBANDINGAN METODE EKSTRAKSI

<p><em>Indonesia has various types of plants those have potential as medicine to overcome health problems in line with the expanding of traditional medicine industry. One example of plants from the Zingiberaceae family is Hedychium coronarium, which is not widely known by the community despite it has efficacy as an antibacterial which is not inferior to other Zingiberaceae family. The research was conducted to determine whether the Hedychium coronarium rhizome shown to have antibacterial activity against the growth of Staphylococcus aureus and Escherichia coli, knowing antibacterial compound that contained in Hedychium coronarium rhizome, also knowing the most effective extraction method to take the antibacterial compound from Hedychium coronarium rhizome. The gandasuli rhizome was extracted by maceration and reflux with 96% ethanol. Antibacterial activity test carried out by the agar diffusion method, and the analysis of antibacterial compounds with bioautography, and the results are monitored with vanillin-sulfuric acid. Maceration and reflux extract at a concentration of 90% has antibacterial activity with inhibition zones, each for 8 and 10 mm against Escherichia coli as well as 9 and 10 mm against Staphylococcus aureus. Bioautography results show a positive effect on the appearance of vanillin-sulfuric acid. Reflux extract has better antibacterial activity, while the antibacterial compound is an essential oil group.</em></p><p><strong> </strong><strong><em>Keywords:</em></strong><strong><em> </em></strong><em>Hedychium coronarium, antibacterial, Staphylococcus aureus, Escherichia coli, bioautography</em><em>.</em></p>

Coronarin D induces apoptotic cell death through the JNK pathway in human hepatocellular carcinoma.

Coronarin D, a diterpene derived from the rhizomes of Hedychium coronarium, has been used to treat inflammatory diseases. Coronarin D can exert strong anticancer effects through cell growth prevention and cell cycle arrest in many cancer cells. In this study, we investigated the molecular mechanism through which coronarin D suppresses cell proliferation and triggers cell death in human hepatocellular carcinoma (HCC) cells. Treatment of Huh7 and Sk-hep-1 cells with coronarin D resulted in a significantly increased loss of mitochondrial membrane potential, leading to the cleavage and activation of caspase-9, caspase-8, and caspase-3 and changes in Bax, Bcl-2, and Bcl-xL protein levels. Coronarin D significantly induced autophagy by increasing the expression of Beclin-1 and LC3-II and reducing the expression of p62. Moreover, Huh7 and Sk-hep-1 cells exposed to coronarin D had decreased expression of phosphorylated AKT, p38, and ERK and increased expression of phosphorylated JNK. Exposure of cells to the JNK-specific inhibitor SP600125 attenuated the apoptotic effects of coronarin D. Taken together, this is the first study to report that coronarin D may effectively inhibit cell growth through apoptosis. We have provided evidence indicating that coronarin D induces cell death through the upregulation of JNK mitogen-activated protein kinases in human HCC cells.

Coronarin D induces reactive oxygen species-mediated cell death in human nasopharyngeal cancer cells through inhibition of p38 MAPK and activation of JNK.

Background and PurposeNasopharyngeal carcinoma (NPC) belongs to squamous cell carcinoma that occurs in the epithelial lining of the nasopharynx. Because of the anatomical position close to the cervical lymph node, some patients have a distant metastasis at the time of diagnosis that leads to treatment failure. Although early stages have a high curability and excellent prognosis, advanced NPC urgently requires new drugs developed to reinforce the effectiveness of therapy without noticeable side effects.Experimental approachCoronarin D (CD), a natural product extracted from the rhizomes of Hedychium coronarium, has been reported to possess anticancer potential. The aim of the present study was to determine the anticancer activity of CD and further elucidate the underlying molecular mechanisms.Key ResultsIn this study, we first demonstrated that CD potently suppressed cell viability in various NPC cell lines. Treatment of cells with CD induced G2/M arrest, apoptosis, and autophagy. Further studies showed that CD increased the production of reactive oxygen species and subsequently activated both autophagy and apoptosis. Moreover, we found that CD-induced activation of p38 and JNK constituted major mechanisms involved in the apoptosis and autophagy triggered by CD. In particular, inhibition of autophagy could strengthen the cytotoxicity of CD, implying that autophagy seems to play a valuable survival and protective role in cancer cells.Conclusions & ImplicationsThese findings provide a promise for the use of CD in combination with autophagy inhibitors for treatment of human NPC cell lines.

Development and validation of an HPTLC method for estimation of coronarin D in Hedychium coronarium rhizome

Rhizome extracts of Hedychium coronarium are widely used as phytotherapeutics. As of date, there is no documented study on the standardization of H. coronarium extract, and the following research is an effort in this direction. Coronarin D is an important bioactive compound present in H. coronarium which shows chemopreventive activity against cancer. H. coronarium extracts were assessed for coronarin D content for the first time. The extraction was checked using different solvents: n-hexane, acetone, and methanol. Coronarin D was separated on silica gel 60F254 high-performance thin-layer chromatography (HPTLC) plates by isocratic gradient method using n-hexane-ethyl acetate (80:20 v/v) as mobile phase. Densitometric quantification was performed at 231 nm in absorption mode. This method gave a well-defined peak at Rf 0.20 corresponding to coronarin D. The method was validated using International Conference on Harmonization (ICH) guidelines in terms of precision, repeatability, and accuracy. Linearity range of coronarin D was 200–1000 ng spot−1 with a correlation coefficient of R2 ± SD = 0.9987 ± 2.62% in the concentration range of 200–1000 ng spot−1. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 35 and 115 ng, respectively. Accuracy of the method was checked by recovery studies conducted at three different concentration levels, and the average percentage recovery was found to be 98.22 % for coronarin D. Among the different solvents, acetone produced maximum extraction efficiency of coronarin D. The proposed HPTLC method can be applied for robust identification and quantitative determination of coronarin D in H. coronarium extracts.

Tetrahydropyran- and tetrahydrofuran-containing diarylheptanoids from Hedychium coronarium rhizomes.

Seven new diarylheptanoids (1-7) were isolated from the n-BuOH-soluble fraction of the rhizome of Hedychium coronarium. Hedycoropyrans A-C (1-3) contain a tetrahydropyran moiety, while hedycorofurans A-D (4-7) contain a tetrahydrofuran moiety, belonging to a rare structural class of diarylheptanoids. Their structures including stereochemistry were elucidated on the basis of 1D and 2D NMR and ECD spectroscopic analyses and HRESIMS data of the parent compounds and the isopropylidene derivatives of 4 and 7.

Chemical characterisation and allelopathic potential of essential oils from leaves and rhizomes of white ginger

Essential oils have the potential to be used as bioherbicides, and possess the advantage of their biodegradability, high structural diversity and reduced natural resistance to weeds. The essential oils of the leaves and rhizomes of Hedychium coronarium, an exotic invasive plant adapted to different regions of Brazil, were extracted by hydrodistillation and characterised chemically by Gas-Liquid Chromatography and Gas-Liquid Chromatography/Mass Spectrometry. Allelopathic activity was determined using methodologies that evaluate the effects of volatility and direct contact on seed germination and seedling vigour in the lettuce. The major constituents of the essential oil from the leaves were β-pinene (46.9%), α-pinene (19.2%) and β-caryophyllene (13.2%) and from the rhizomes, β-pinene (41.5%), 1.8-cineole (23.6%) and α-pinene (13.1%). When analysing the volatile effects of the essential oils, it was seen that their concentration did not affect seedling first germination count or total germination. The essential oil from the rhizomes was more effective than the essential oil from the leaves in reducing seedling response for SGI, dry weight, and length of the roots and shoots. When evaluating the effect of direct contact with the essential oils, it was seen that both oils reduced the response of all the variables under evaluation, and that in addition, the oil from the rhizomes caused greater reductions than that from the leaves, again for all variables. These results can be attributed to the higher levels of monoterpenes present in the essential oil from the rhizomes, mainly the presence of 1.8-cineole.

Antimicrobial activity of coronarin D and its synergistic potential with antibiotics.

Coronarin D is a labdane-type diterpene from the rhizomes of Hedychium coronarium. In the view of our ongoing effort to explore its novel biological activity, antimicrobial activity study of coronarin D was performed. The results showed that coronarin D was active against tested Gram-positive bacteria, inactive for tested Gram-negative bacteria, and weakly active against tested fungi. The antibacterial effect of the combination of coronarin D with nine classical antibiotics against four Gram-positive bacteria was also evaluated. The fractional inhibitory concentration indices (FICI) of coronarin D-antibiotics combinations, calculated from the checkerboard assay, were used as synergism indicator. Out of 36 combinations, 47% showed total synergism, 33% had partial synergistic interaction, 17% showed no effect, and 3% showed antagonism. By combination with coronarin D at concentration of 0.25 minimal inhibitory concentration (MIC), the activities of antibiotics were boosted to 4- to 128-fold. These finding suggested an attractive approach to combat the infectious diseases by using coronarin D-antibiotic drug combination.