Boesenbergia Pandurata Roxb., An Indonesian Medicinal Plant: Phytochemistry, Biological Activity, Plant Biotechnology

The Nephroprotective Activity of Boesenbergia Rotunda Rhizome by Reducing Creatinine, Urea Nitrogen, Glutamic Pyruvic Transaminase, and Malondialdehyde Levels in the Blood and Attenuating the Expression of Havcr1 (KIM-1), Lcn2 (NGAL), Casp3, and Casp7 Genes in the Kidney Cortex of Cisplatin-Induced Sprague-Dawley Rats

Background

Cisplatin chemotherapy induces nephrotoxicity by producing reactive oxygen species, hence, discovering add-on nephroprotective drugs for patients with cancer is challenging. Boesenbergia rotunda has been reported for its antioxidant properties.

Purpose

This study aims to explore the nephroprotective mechanism of the ethanol extract of Boesenbergia rotunda rhizome (EEBR) in cisplatin-induced rats.

Methods

The rats were randomly assigned into 6 groups: the normal control (treated with saline); the negative control (cisplatin-induced without any treatment); the positive control (treated with quercetin 50 mg/kg BW); and 3 treatment EEBR (125 mg/kg BW; 250 mg/kg BW; 500 mg/kg BW) groups for 10 days. The % relative organ weight, kidney histopathology, and nephrotoxicity biomarkers expression were evaluated.

Results

EEBR decreased creatinine, urea nitrogen, glutamic pyruvate transaminase, and malondialdehyde levels in the blood of cisplatin-induced rats. An insignificant increase in GOT was observed in rats treated with the highest dose of EEBR. EEBR did not significantly alter the BW and the % kidney relative weight. An abnormal shape of the Bowman capsule is observed in the negative control group. EEBR reduced the expression of Havcr1 (KIM-1), Lcn2 (NGAL), Casp3, and Casp7 genes in rats' kidneys.

Conclusion

Boesenbergia rotunda could be considered a potential candidate for add-on therapy in cisplatin-treated patients, but further studies are needed to verify its efficacy and safety.

In vitro investigation on Pennisetum purpureum leaf extracts grown in Indonesia of phytochemical components, optical characteristics, and antioxidant-antibacterial activities

Medicinal plants hold significant cultural significance and play a crucial role in the advancement of potentially safe drugs for the therapy of disease worldwide. Pennisetum purpureum or elephant grass has been used for traditional medications in Indonesia without understanding the phytochemicals of those plants. Herein, our report revolves around the qualitative and quantitative examination of phytochemical components, optical properties, antioxidants, and antibacterial assessments of solvent fractions derived from Pennisetum purpureum leaf. The Pennisetum purpureum leaf was successfully soaked with ethanol, n-hexane, and chloroform. The study aimed to assess the total phenolic content (TPC), total flavonoid content (TFC), and total alkaloid content (TAC) within different of extracts. The optical properties of extract were analyzed by absorption light and photoluminescent. Moreover, evaluation of antioxidant activities of extracts through DPPH free radical scavenging and FRAP assays, followed by an evaluation of their effectiveness in antibacterial therapy against different bacterial strains. The qualitative and quantitative phytochemical of Pennisetum purpureum presented as highest in ethanol TPC (85.5 mg GAE/g extracts), TFC (87.9 mg QE/g extracts), and TAC (86.2 mg ATE/g extracts) as compared to other solvents extract. Pennisetum purpureum extract had antioxidant capacity against DPPH radical and FRAP assay. Furthermore, each of the samples displayed antibacterial effectiveness that was dependent on the dosage towards different strains of bacteria. Our findings clearly demonstrated that Pennisetum purpureum leaf extracts grown in Indonesia containing alkaloid, flavonoid, glycoside, saponin, steroids, tannin, and terpenoids that support its capability as antioxidant and antibacterial.

<em>In vitro</em> study of pinostrobin propionate and pinostrobin butyrate: Cytotoxic activity against breast cancer cell T47D and its selectivity index

Backgrounds: Pinostrobin has the potential activity as an anti-cancer. However, its activity is still lower than the anticancer drugs on the market. To increase its activity, pinostrobin derivatives have been synthesized, namely pinostrobin propionate and pinostrobin butyrate, which are predicted to have better activity and lower toxicity than pinostrobin after being tested by in silico approach. So the compound deserves to be tested for its anticancer activity and selectivity on normal cells. Objective: This study aims to determine the anticancer activity of pinostrobin propionate and pinostrobin butyrate against the T47D breast cancer cell line and its selectivity against the Vero cell line. Methods: The cytotoxicity test which is anticancer activity test and its selectivity on normal cell were carried out using the MTT(3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. The cells used were breast cancer cell line T47D and normal Vero cells. The test results were analyzed using a microplate reader with a wavelength of 570 nm. Results: From the analysis of anticancer activity on T47D cells, the IC50 values of pinostrobin, pinostrobin propionate, and pinostrobin butyrate were 2.93, 0.57, and 0.40 mM, respectively. While the results of the cytotoxicity test on Vero cells obtained the CC50 value of pinostrobin, pinostrobin propionate, pinostrobin butyrate was 1.27, 0.94, and 0.89 mM, respectively. So the SI value of pinostrobin (SI=0.4) is smaller than its derivatives (SI=1.7 and 2.2). Meanwhile, pinostrobin butyrate is more selective than pinostrobin propionate. Conclusions: It can be concluded that pinostrobin propionate and pinostrobin butyrate compounds have greater activity and selectivity than pinostrobin so these compounds are promising to be further developed as anticancer candidates.

Inhibitory Effect of Isopanduratin A on Adipogenesis: A Study of Possible Mechanisms

The root of Boesenbergia rotunda, a culinary plant commonly known as fingerroot, has previously been reported to possess anti-obesity activity, with four flavonoids identified as active principles, including pinostrobin, panduratin A, cardamonin, and isopanduratin A. However, the molecular mechanisms underlying the antiadipogenic potential of isopanduratin A remain unknown. In this study, isopanduratin A at non-cytotoxic concentrations (1-10 μM) significantly suppressed lipid accumulation in murine (3T3-L1) and human (PCS-210-010) adipocytes in a dose-dependent manner. Downregulation of adipogenic effectors (FAS, PLIN1, LPL, and adiponectin) and adipogenic transcription factors (SREBP-1c, PPARγ, and C/EBPα) occurred in differentiated 3T3-L1 cells treated with varying concentrations of isopanduratin A. The compound deactivated the upstream regulatory signals of AKT/GSK3β and MAPKs (ERK, JNK, and p38) but stimulated the AMPK-ACC pathway. The inhibitory trend of isopanduratin A was also observed with the proliferation of 3T3-L1 cells. The compound also paused the passage of 3T3-L1 cells by inducing cell cycle arrest at the G0/G1 phase, supported by altered levels of cyclins D1 and D3 and CDK2. Impaired p-ERK/ERK signaling might be responsible for the delay in mitotic clonal expansion. These findings revealed that isopanduratin A is a strong adipogenic suppressor with multi-target mechanisms and contributes significantly to anti-obesogenic activity. These results suggest the potential of fingerroot as a functional food for weight control and obesity prevention.

Total synthesis of (-)-panduratin D

Herein, an enantioselective total synthesis of (-)-panduratin D, a novel secondary metabolite against human pancreatic PANC-1 cancer cell, from commercially available 3-methoxyphenol is reported. The synthesis was completed in nine steps and the key features include Sonogashira coupling, anionic Snieckus-Fries rearrangement, directed ortho metalation, tandem Si → C Alkyl rearrangement/Claisen-Schmidt condensation, and chiral boron complex-promoted asymmetric Diels-Alder cycloaddition. These endeavors could facilitate the biological studies of (-)-panduratin D and its analogs.

Induction of apoptosis in human colorectal cancer cells by nanovesicles from fingerroot (Boesenbergia rotunda (L.) Mansf.)

Colorectal cancer is the leading cause of cancer-related deaths worldwide, warranting the urgent need for a new treatment option. Plant-derived nanovesicles containing bioactive compounds represent new therapeutic avenues due to their unique characteristics as natural nanocarriers for bioactive molecules with therapeutic effects. Recent evidence has revealed potential anticancer activity of bioactive compounds from Boesenbergia rotunda (L.) Mansf. (fingerroot). However, the effect and the underlying mechanisms of fingerroot-derived nanovesicles (FDNVs) against colorectal cancer are still unknown. We isolated the nanovesicles from fingerroot and demonstrated their anticancer activity against two colorectal cancer cell lines, HT-29 and HCT116. The IC50 values were 63.9 ± 2.4, 57.8 ± 4.1, 47.8 ± 7.6 μg/ml for HT-29 cells and 57.7 ± 6.6, 47.2 ± 5.2, 34 ± 2.9 μg/ml for HCT116 cells at 24, 48, and 72 h, respectively. Interestingly, FDNVs were not toxic to a normal colon epithelial cell line, CCD 841 CoN. FDNVs exhibited selective uptake by the colorectal cancer cell lines but not the normal colon epithelial cell line. Moreover, dose- and time-dependent FDNV-induced apoptosis was only observed in the colorectal cancer cell lines. In addition, reactive oxygen species levels were substantially increased in colorectal cancer cells, but total glutathione decreased after treatment with FDNVs. Our results show that FDNVs exhibited selective anticancer activity in colorectal cancer cell lines via the disruption of intracellular redox homeostasis and induction of apoptosis, suggesting the utility of FDNVs as a novel intervention for colorectal cancer patients.

Toward the use ofBoesenbergia rotundaextracts and the chalcone panduratin A to treat periodontitis

Novel affordable medications are needed to treat chronic periodontitis, which is one of the most common dental pathologies worldwide. Extracts prepared from the rhizome of the medicinal plant Boesenbergia rotunda (L.) Mansf., commonly known as fingerroot, are used to treat a variety of human pathologies. These extracts contain potent anti-inflammatory compounds, including the chalcone derivative panduratin A (Pa-A), which is the lead compound of a series of analogues, designated panduratins A to Y. The anti-inflammatory properties of the extracts of B. rotunda and the most abundant bioactive products found in these extracts (including Pa-A, 4-hydroxyoanduratin, isopanduratin, and others) have been reviewed. A standardized extract of the plant has promising utility in the treatment of gingival inflammation. The effects are characterized by three actions: (i) a direct antimicrobial effect against fungi and oral pathogens such as Porphyromonas gingivalis, (ii) a marked anti-inflammatory effect via a reduced production of mediators, like prostaglandin E2 and different interleukins, and (iii) a dual bone-preserving effect, with a reduction in bone resorption and an increase in bone formation. Acting as a protease inhibitor, Pa-A is one of the main active ingredients of the extract, implicated in these actions. A Pa-A-standardized extract of B. rotunda has been used in humans for treating dyspepsia. The product is safe and well-tolerated. The development of panduratin-containing dental products, for the prevention and treatment of periodontitis, has been proposed. The structural analogues, Pa-A to-Y, should also be investigated for the treatment of dental inflammation.

Combination of natural antivirals and potent immune invigorators: A natural remedy to combat COVID-19

The flare‐up in severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) that emerged in December 2019 in Wuhan, China, and spread expeditiously worldwide has become a health challenge globally. The rapid transmission, absence of anti‐SARS‐CoV‐2 drugs, and inexistence of vaccine are further exacerbating the situation. Several drugs, including chloroquine, remdesivir, and favipiravir, are presently undergoing clinical investigation to further scrutinize their effectiveness and validity in the management of COVID‐19. Natural products (NPs) in general, and plants constituents specifically, are unique sources for various effective and novel drugs. Immunostimulants, including vitamins, iron, zinc, chrysin, caffeic acid, and gallic acid, act as potent weapons against COVID‐19 by reinvigorating the defensive mechanisms of the immune system. Immunity boosters prevent COVID‐19 by stimulating the proliferation of T‐cells, B‐cells, and neutrophils, neutralizing the free radicals, inhibiting the immunosuppressive agents, and promoting cytokine production. Presently, antiviral therapy includes several lead compounds, such as baicalin, glycyrrhizin, theaflavin, and herbacetin, all of which seem to act against SARS‐CoV‐2 via particular targets, such as blocking virus entry, attachment to host cell receptor, inhibiting viral replication, and assembly and release.

Boesenmaxane Diterpenoids from Boesenbergia maxwellii

Three new diterpenoids, boesenmaxanes A-C (1-3), with an unprecedented core skeleton consisting of an unusual C-C bond between C-12 and an exo-cyclic methylene C-13, were isolated from the rhizome extracts of Boesenbergia maxwellii. The structures were elucidated by analysis of spectroscopic and X-ray diffraction data. Electronic circular dichroism spectra were used to determine the absolute configuration. All the isolates were evaluated for their cytotoxic effects, anti-HIV activity, and antimicrobial activity. Boesenmaxanes A and C (1 and 3) showed significant inhibitory activity in the syncytium reduction assay, with EC₅₀ values of 55.2 and 27.5 μM, respectively.

Protective Effect of Panduratin A on Cisplatin-Induced Apoptosis of Human Renal Proximal Tubular Cells and Acute Kidney Injury in Mice

BACKGROUND

Cisplatin is an effective chemotherapy but its main side effect, acute kidney injury, limits its use. Panduratin A, a bioactive compound extracted from Boesenbergia rotunda, shows several biological activities such as anti-oxidative effects. The present study investigated the nephroprotective effect of panduratin A on cisplatin-induced renal injury.

METHODS

We investigated the effect of panduratin A on the toxicity of cisplatin in both mice and human renal cell cultures using RPTEC/TERT1 cells.

RESULTS

The results demonstrated that panduratin A ameliorates cisplatin-induced renal toxicity in both mice and RPTEC/TERT1 cells by reducing apoptosis. Mice treated with a single intraperitoneal (i.p.) injection of cisplatin (20 mg/kg body weight (BW)) exhibited renal tubule injury and impaired kidney function as shown by histological examination and increased serum creatinine. Co-administration of panduratin A (50 mg/kg BW) orally improved kidney function and ameliorated renal tubule injury of cisplatin by inhibiting activation of extracellular signal-regulated kinase (ERK)1/2 and caspase 3. In human renal proximal tubular cells, cisplatin induced cell apoptosis by activating pro-apoptotic proteins (ERK1/2 and caspase 3), and reducing the anti-apoptotic protein (Bcl-2). These effects were significantly ameliorated by co-treatment with panduratin A. Interestingly, panduratin A did not alter intracellular accumulation of cisplatin. It did not alter the anti-cancer efficacy of cisplatin in either human colon or non-small cell lung cancer cell lines.

CONCLUSIONS

The present study highlights panduratin A has a potential protective effect on cisplatin's nephrotoxicity.

Emerging roles of cardamonin, a multitargeted nutraceutical in the prevention and treatment of chronic diseases

Although chronic diseases are often caused by the perturbations in multiple cellular components involved in different biological processes, most of the approved therapeutics target a single gene/protein/pathway which makes them not as efficient as they are anticipated and are also known to cause severe side effects. Therefore, the pursuit of safe, efficacious, and multitargeted agents is imperative for the prevention and treatment of these diseases. Cardamonin is one such agent that has been known to modulate different signaling molecules such as transcription factors (NF-κB and STAT3), cytokines (TNF-α, IL-1β, and IL-6) enzymes (COX-2, MMP-9 and ALDH1), other proteins and genes (Bcl-2, XIAP and cyclin D1), involved in the development and progression of chronic diseases. Multiple lines of evidence emerging from pre-clinical studies advocate the promising potential of this agent against various pathological conditions like cancer, cardiovascular diseases, diabetes, neurological disorders, inflammation, rheumatoid arthritis, etc., despite its poor bioavailability. Therefore, further studies are paramount in establishing its efficacy in clinical settings. Hence, the current review focuses on highlighting the underlying molecular mechanism of action of cardamonin and delineating its potential in the prevention and treatment of different chronic diseases.

Vasorelaxant Effect of Boesenbergia rotunda and Its Active Ingredients on an Isolated Coronary Artery

Cardiovascular diseases are a major cause of death in developed countries. The regulation of vascular tone is a major approach to prevent and ameliorate vascular diseases. As part of our ongoing screening for cardioprotective natural compounds, we investigated the vasorelaxant effect of rhizomes from Boesenbergia rotunda (L.) Mansf. [Boesenbergia pandurata (Roxb.) Schltr.] used as a spice and herbal medicine in Asian countries. The methanol extract of B. rotunda rhizomes (BRE) exhibited significant vasorelaxation effects ex vivo at EC₅₀ values of 13.4 ± 6.1 μg/mL and 40.9 ± 7.9 μg/mL, respectively, with and without endothelium in the porcine coronary artery ring. The intrinsic mechanism was evaluated by treating with specific inhibitors or activators that typically affect vascular reactivity. The results suggested that BRE induced relaxation in the coronary artery rings via an endothelium-dependent pathway involving NO-cGMP, and also via an endothelium-independent pathway involving the blockade of Ca²⁺ channels. Vasorelaxant principles in BRE were identified by subsequent chromatographic methods, which revealed that flavonoids regulate vasorelaxant activity in BRE. One of the flavonoids was a Diels-Alder type adduct, 4-hydroxypanduratin A, which showed the most potent vasorelaxant effect on porcine coronary artery with an EC₅₀ of 17.8 ± 2.5 μM. Our results suggest that rhizomes of B. rotunda might be of interest as herbal medicine against cardiovascular diseases.

Docking Study on Anti-HIV-1 Activity of Secondary Metabolites from Zingiberaceae Plants

Introduction:

Human immunodeficiency virus type-1 (HIV-1) that causes acquired immunodeficiency syndrome (AIDS) has become a worldwide health problem today. There are approximately 30 anti-HIV-1 drugs that have been used in the treatment of AIDS. However, effective anti HIV-1 agents with less side affect and high inhibition potency are still in demand.

Objective:

The objective of this study was to identify the potential compounds from Zingiberaceae plants that might be active as anti-HIV-1 by molecular docking.

Materials and Methods:

Molecular docking simulation was performed by using AutoDock 4.2 on Linux operation system. Docking protocol was validated by using root mean square deviation (RMSD) value using redocking and cross-docking methods. The reported metabolites from Zingiberaceae plants were docked on HIV-1 protease, integrase, and reverse transcriptase protein enzymes.

Results:

The docking result showed that the genera of Zingiber, Etlingera, Alpinia, Hedychium, and Boesenbergia have potential metabolites that inhibit HIV protease, integrase, and reverse transcriptase enzymes by possessing lower docking energy than native ligand of amprenavir, raltegravir, and nevirapine. Among the metabolites, noralpindenoside B and alpindenoside A from Alpinia densespicata inhibited protease enzymes with the lowest docking energy of -18.02 and -17.90 kcal/mol, respectively. Meanwhile, panduratin E from Boesenbergia pandurata Roxb. and 5α,8α-epidioxyergosta-6,22-dien-3β-ol from Etlingera elatior showed the lowest docking energy on integrase protein with docking energy of -11.97 and -11.41 kcal/mol, respectively. Pahangensin A from Alpinia pahangensis Ridley showed the lowest docking energy on reverse transcriptase enzyme with docking energy of -13.76 kcal/mol.

Conclusion:

The docking molecular study has identified the possible potential compounds from Zingiberaceae plants that might be used for anti-HIV-1 treatment. So, this study suggested further isolation and purification of the predicted compounds.

Boesenbergia rotunda extract inhibits Candida albicans biofilm formation by pinostrobin and pinocembrin

ETHNOPHARMACOLOGICAL RELEVANCE

Boesenbergia rotunda (L.) Mansf. (Zingiberaceae) is an indigenous plant of Southeast Asia. Based on ethnopharmacological use, the rhizome is recommended in the treatment of stomachache, leukoplakia, abscesses, and leukorrhea in Thailand primary health care system. Candida albicans often causes leukorrhea, and infection of many mucosal sites. Its infection leads to serious illness.

AIM OF THE STUDY

This study aimed to investigate the effects of the ethanolic extract of the B. rotunda rhizome on C. albicans ATCC10231 in the stages of planktonic and biofilm formation and to explore the underlying mechanisms.

MATERIALS AND METHODS

The chemical composition of the extract was determined using ultra-performance liquid chromatography (UPLC). The planktonic growth of C. albicans was evaluated by the microdilution method, following EUCAST guidelines. For each stage of biofilm formation, the biofilm was assessed by the MTT assay. The biofilm structure was examined under a light microscope. The degree of cell surface hydrophobicity was measured. The mRNA levels of ALS1, ALS3, and ACT1 were determined by RT-qPCR.

RESULTS

The extract of B. rotunda consisted of 25% (w/w) pinostrobin and 12% (w/w) pinocembrin. All stages of C. albicans biofilm formation were significantly inhibited by the extract, whereas the planktonic growth did not change. Biofilm development greatly decreased due to the extract in a concentration-dependent manner, with an IC₅₀ value of 17.7 μg/mL. Pinostrobin and pinocembrin demonstrated inhibitory effects during this stage. These results were in accordance with the microscopic evaluation. The filamentous form decreased with pinocembrin rather than pinostrobin. Moreover, the cell surface hydrophobicity was significantly decreased by 6.25 and 12.5 μg/mL of the extract and 100 μM of pinocembrin. The ALS3 mRNA level was noticeably decreased by 12.5 μg/mL of the extract, 100 μM of pinostrobin, and 100 μM of pinocembrin. The ACT1 mRNA level decreased significantly with pinocembrin. However, the ALS1 mRNA level was not altered following all treatments.

CONCLUSION

The ethanolic extract of B. rotunda could inhibit biofilm formation of C. albicans, especially during the biofilm development stage, by means of reducing the cell surface hydrophobicity and suppressing the ALS3 mRNA expression. Pinocembrin had a stronger effect on ALS3 mRNA expression than pinostrobin. Only pinocembrin significantly decreased the ACT1 mRNA level.

Cardamonin: A new player to fight cancer via multiple cancer signaling pathways

Nature's pharmacy has undoubtedly served humans as an affordable and safer health-care regime for a long times. Cardamonin, a chalconoid present in several plants has been known for a longtime to have beneficial properties towards human health. In this review, we aimed to highlight the recent advances achieved in discovering the pharmacological properties of cardamonin. Cardamonin is cardamom-derived chalcone, which plays a role in cancer treatment, immune system modulation, inflammation and pathogens killing. Through the modulation of cellular signaling pathways, cardamonin activates cell death signal to induce apoptosis in malignant cells that results in the inhibition of cancer development. Moreover, cardamonin arrests cell cycle by altering the expression of regulatory proteins during malignant cells division. Due to its relatively selective cytotoxic potential against host malignant cells, cardamonin is emerging as a promising novel experimental anticancer agent. The potential of cardamonin to target various signaling molecules, transcriptional factors, cytokines and enzymes, such as mTOR, NF-κB, Akt, STAT3, Wnt/β-catenin and COX-2 enhances the opportunity to explore it as a new multi-target therapeutic agent. The pharmacokinetic and biosafety profile of cardamonin favor it as a potentially safe biomolecule for pharmaceutical drug development.

Dinorcassane Diterpenoid from Boesenbergia rotunda Rhizomes Collected in Lower Myanmar

A new dinorcassane diterpenoid, seikphoochinal A (1), and four known compounds, pinostrobin (2), 4',7-dimethylkaempferol (3), and galanals A (4) and B (5), were isolated from the chloroform-soluble crude extract of wild type Boesenbergia rotunda rhizomes collected in Lower Myanmar. The chemical structures of these compounds were identified, using a combination of spectroscopic methods. The presence of the diterpenoids 1, 4, and 5 demonstrated the structural diversity of wild type B. rotunda. Among the isolates, compounds 4 and 5 exhibited significant antiproliferative activities against a small panel of human cancer cell lines, including lung (LK-2, A549), stomach (ECC4), breast (MCF7), cervix (HeLa), and prostate (DU145).

Boesenbergia rotunda (L.) Mansf. extract potentiates the antibacterial activity of some β-lactams against β-lactam-resistant staphylococci

OBJECTIVES

The purpose of this study was to investigate the effect of Boesenbergia rotunda (L.) Mansf. extract (BRE) and peptidoglycan inhibitor antibiotics, alone and in combination, against β-lactam-resistant staphylococci.

METHODS

Antibacterial and synergistic activities of BRE alone and in combination with ampicillin (AMP), cloxacillin (CLX), cefazolin (CZO) or vancomycin (VAN) were evaluated against two β-lactam-resistant Staphylococcus aureus (BRSA) isolates and one β-lactam-resistant Staphylococcus epidermidis (BRSE) isolate. The activities were confirmed by killing curve assays. The preliminary antimicrobial action was elucidated by transmission electron microscopy (TEM) and cytoplasmic membrane (CM) permeability assay.

RESULTS

All tested staphylococci were inhibited by BRE at a minimum inhibitory concentration (MIC) of 16μg/mL. Two BRSA strains showed high resistance to CLX, AMP and CZO, whilst BRSE was resistant to CLX and AMP. All tested isolates remained susceptible to VAN. Chequerboard assay demonstrated a fractional inhibitory concentration index (FICI) of 0.50 for the BRE+CLX combination against the BRSA strains. Killing curve determinations confirmed the antibacterial and synergistic activities. TEM revealed collapse of the CM in BRE-treated cells and damage both of the CM and peptidoglycan (PG) in BRE+CLX-treated cells. The CM permeability assay showed that either BRE or nisin alone as well as BRE+CLX significantly induced leakage of OD_260nm-absorbing materials.

CONCLUSIONS

BRE potentiated the activity of β-lactams, particularly CLX, against β-lactam-resistant staphylococci by damaging the CM and PG layer, leading to leakage of intracellular material. Combination of BRE and β-lactams provides a potential way forward in developing novel antistaphylococcal agents.

New Biflavonoids with α-Glucosidase and Pancreatic Lipase Inhibitory Activities from Boesenbergia rotunda

Roots of Boesenbergia rotunda (L.) Mansf. are prominent ingredients in the cuisine of several Asian countries, including Thailand, Malaysia, Indonesia, India, and China. An extract prepared from the roots of this plant showed strong inhibitory activity against enzymes α-glucosidase and pancreatic lipase and was subjected to chromatographic separation to identify the active components. Three new biflavonoids of the flavanone-chalcone type (9, 12, and 13) were isolated, along with 12 known compounds. Among the 15 isolates, the three new compounds showed stronger inhibitory activity against α-glucosidase than the drug acarbose but displayed lower pancreatic lipase inhibitory effect than the drug orlistat. The results indicated the potential of B. rotunda roots as a functional food for controlling after-meal blood glucose levels.

Identification of PGC-1α activating constituents in Zingiberaceous crude drugs

The activity of Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) as an index of thermogenesis induced by four Indonesian Zingiberaceous crude drugs, Boesenbergia rotunda, Curcuma longa, Kaempferia galanga, Zingiber montanum, was examined, and GC-MS analyses of extracts of these drugs were performed. The results showed that activation of PGC-1α by K. galanga was high, whereas no activation was shown for the other drugs. Ethyl p-methoxycinnamate and ethyl cinnamate were identified as the PGC-1α activating compounds of K. galanga. Furthermore, study on the structure-activity relationship revealed that ethyl p-methoxycinnamate has the strongest activity among the cinnamic acid derivatives. This suggests that the ester structure and the methoxy group are important factors responsible for the PGC-1α activity.

Southeast Asian Medicinal Plants as a Potential Source of Antituberculosis Agent

Despite all of the control strategies, tuberculosis (TB) is still a major cause of death globally and one-third of the world's population is infected with TB. The drugs used for TB treatment have drawbacks of causing adverse side effects and emergence of resistance strains. Plant-derived medicines have since been used in traditional medical system for the treatment of numerous ailments worldwide. There were nine major review publications on antimycobacteria from plants in the last 17 years. However, none is focused on Southeast Asian medicinal plants. Hence, this review is aimed at highlighting the medicinal plants of Southeast Asian origin evaluated for anti-TB. This review is based on literatures published in various electronic database. A total of 132 plants species representing 45 families and 107 genera were reviewed; 27 species representing 20.5% exhibited most significant in vitro anti-TB activity (crude extracts and/or bioactive compounds 0–<10 µg/ml). The findings may motivate various scientists to undertake the project that may result in the development of crude extract that will be consumed as complementary or alternative TB drug or as potential bioactive compounds for the development of novel anti-TB drug.

Boesenberols, Pimarane Diterpenes with TRAIL-Resistance-Overcoming Activity from Boesenbergia pandurata

TRAIL is a potent and selective inducer of apoptosis in most cancer cells while sparing normal cells, which makes it an attractive target for the development of new cancer therapies. In a screening program on natural resources with the ability to abrogate TRAIL resistance, the bioassay-guided fractionation of Boesenbergia pandurata rhizomes resulted in the isolation of 17 pimarane diterpenes and a monoterpene. Among these, compounds 1-8, named boesenberols A-H, are new pimarane diterpenes. All compounds exhibited TRAIL-resistance-overcoming activity in TRAIL-resistant AGS cells. Subtoxic doses of the major compound 9 sensitized AGS cells to TRAIL-induced apoptosis by up-regulating apoptosis-inducing proteins, such as DR4, DR5, p53, Fas, CHOP, Bak, and cleaved caspases-3, -8, and -9, and down-regulating the levels of cell survival proteins, such as Bcl-2, c-FLIP, and GSK-3β, in TRAIL-resistant AGS cells. Furthermore, compound 9 did not decrease the viability of noncancerous (HEK293) cells at concentrations up to 30 μM.