Garcinia mangostana hydrogel patch: bactericidal activity and clinical safety for acne vulgaris treatment.

Background and purpose: Garcinia mangostana, simply known as mangosteen, has long been used by Thai traditional medicine because of its reported antibacterial and anti-inflammatory activities for the treatment of skin infections. In this study, mangosteen pericarps were developed into a hydrogel patch to eradicate acne-inducing bacteria. Experimental procedure: The G. mangostana extract was investigated for bactericidal activity. A hydrogel patch containing the extract was examined for mechanical properties, antibacterial activity, in vitro release, skin permeation, and a phase I clinical study of skin irritation and allergic testing by a closed patch test. Finding/Results: The G. mangostana hydrogel patch made from carrageenan and locust bean gum powders was yellow in color, smooth, durable, and flexible. This G. mangostana hydrogel patch was effective against Cutibacterium acnes, Staphylococcus epidermidis, and Staphylococcus aureus. The active ingredient, α-mangostin, was released and permeated from the G. mangostana hydrogel patch within the first 30 min at 33.16 ± 0.81% and 32.96± 0.97%, respectively. The G. mangostana hydrogel patch showed no irritation in 30 healthy volunteers. However, two volunteers had delayed allergic contact dermatitis to 0.5% (w/w) G. mangostana hydrogel patch. Conclusion and implication: This hydrogel patch containing G. mangostana ethanolic extract is not recommended for patients who have any reaction to mangosteen but has utility as an anti-acne facial mask.

Alpha-Mangostin-Loaded Transferrin-Conjugated Lipid-Polymer Hybrid Nanoparticles: Development and Characterization for Tumor-Targeted Delivery.

Alpha-mangostin, a natural xanthone mainly extracted from the pericarp of Garcinia mangostana, has been shown to have promising anticancer properties in many types of cancer. However, the therapeutic potential of α-mangostin has been limited so far due to its poor aqueous solubility and low oral bioavailability, which limited its biopharmaceutical applications. Furthermore, α-mangostin failed to specifically reach tumors at a therapeutic concentration due and rapid elimination in vivo. We hypothesized that this drawback could be overcome by loading the drug within a delivery system conjugated to transferrin (Tf), whose receptors are overexpressed on many cancer cells and would enhance the specific delivery of α-mangostin to cancer cells, thereby enhancing its therapeutic efficacy. The objectives of this study were therefore to prepare and characterize transferrin-conjugated lipid-polymer hybrid nanoparticles (LPHN) entrapping α-mangostin, as well as to evaluate their therapeutic efficacy in vitro. We successfully prepared α-mangostin loaded LPHN using a one-step nanoprecipitation method with high drug entrapment efficiency. The conjugation of Tf to the LPHN was achieved by using the thiol-maleimide "click" reaction, leading to an increase in the particle hydrodynamic size of Tf-LPHN compared to that of unconjugated (control) LPHN (Ctrl-LPHN). Both Tf-LPHN and Ctrl-LPHN were bearing negative surface charges. Tf-LPHN and Ctrl-LPHN exhibited a sustained release of α-mangostin at pH 7.4, following an initial burst release, unlike rapid release of drug solution. The entrapment of α-mangostin in the LPHN led to an increase in α-mangostin uptake by cancer cells, and thus improved its antiproliferative activity compared to that observed with the drug solution. In conclusion, α-mangostin entrapped in the Tf-LPHN is therefore a highly promising therapeutic system that should be further optimized as therapeutic tools for cancer treatment.

Anti-Inflammatory Investigations of Extracts of Zanthoxylum rhetsa.

Zanthoxylum rhetsa has been consumed in the diet in northern Thailand and also used as a medicament in ancient scripture for arthropathies. Thus, this study aimed to evaluate the activity of various extracts from differential parts of Z. rhetsa via inhibition of inflammatory mediators (NO, TNF-α, and PGE2) in RAW264.7 macrophages. The chemical composition in active extracts was also analyzed by GC/MS. The parts of this plant studied were whole fruits (F), pericarp (P), and seed (O). The methods of extraction included maceration in hexane, 95% ethanol and 50% ethanol, boiling in water, and water distillation. The results demonstrated that the hexane and 95% ethanolic extract from pericarp (PH and P95) and seed essential oil (SO) were the most active extracts. PH and P95 gave the highest inhibition of NO production with IC50 as 11.99 ± 1.66 µg/ml and 15.33 ± 1.05 µg/ml, respectively, and they also showed the highest anti-inflammatory effect on TNF-α with IC50 as 36.08 ± 0.55 µg/ml and 34.90 ± 2.58 µg/ml, respectively. PH and P95 also showed the highest inhibitory effect on PGE2 but less than SO with IC50 as 13.72 ± 0.81 µg/ml, 12.26 ± 0.71 µg/ml, and 8.61 ± 2.23 µg/ml, respectively. 2,3-Pinanediol was the major anti-inflammatory compound analyzed in PH (11.28%) and P95 (19.82%) while terpinen-4-ol constituted a major anti-inflammatory compound in SO at 35.13%. These findings are the first supportive data for ethnomedical use for analgesic and anti-inflammatory activity in acute (SO) and chronic (PH and P95) inflammation.

Ethnopharmacological analysis from Thai traditional medicine called prasachandaeng remedy as a potential antipyretic drug.

ETHNOPHARMACOLOGICAL RELEVANCE: Prasachandaeng (PSD) remedy is a famous antipyretic drug for adults and children in Thai traditional medicine used and is described in Thailand's National List of Essential Medicine. Relationship between the taste of this herbal medicine, ethnopharmacological used and its pharmacological properties was reviewed. AIMS OF STUDY: Since there has been no scientific report on the antipyretic activity of PSD, aim of this study was to investigate the efficacy related antipyretic drug of the remedy and its 12 herbal ingredients. It involved quality evaluation of raw materials, extraction of PSD and its ingredients, in vitro evaluation of their inhibitory activities on fever mediators, i.e. NO and PGE2 production in murine macrophage (RAW 264.7) cell line stimulated by lipopolysaccharide, and its stability study of the 95% ethanolic extract of PSD remedy. MATERIALS AND METHODS: PSD remedy was extracted by maceration with 50% and 95% ethanol (PSD50 and PSD95), by decoction with distilled water (PSDW), and hydrolysis of PSDW with 0.1 N HCl (PSDH). The 12 plant ingredients were extracted with 95% ethanol. Quality evaluation of PSD ingredients was performed according to the standard procedures for the quality control of herbal materials. The inhibitory activity on nitric oxide production was determined by the Griess reaction and the inhibition of prostaglandin E2 production was determined using the ELISA test kit. RESULTS: PSD ingredients passed the quality standard stipulated for herbal materials. PSD95 exhibited the highest inhibitory activities on the production of NO and PGE2 with the IC50 values of 42.40 ± 0.72 and 4.65 ± 0.76 µg/mL, respectively. A standard drug acetaminophen (ACP) exhibited inhibition of NO and PGE2 production with the IC50 values of 99.50 ± 0.43 and 6.110 ± 0.661 µg/mL, respectively. The stability study was suggested two years shelf-life of PSD95. This is the first report on the activity related antipyretic activity of PSD remedy and its ingredients against two fever mediators, NO and PGE2. CONCLUSION: The results suggested that the 95% ethanolic extracts of PSD remedy and some of its ingredients, were better than ACP in reducing fever. PSD should be further studied using in vivo models and clinical trials to support its use as an antipyretic drug in Thai traditional medicine.

Bactericidal Effect and Anti-Inflammatory Activity of Cassia garettiana Heartwood Extract.

Natural products are used as alternative drugs in traditional medicine to treat infection and inflammation and relieve pain. Heartwood of Cassia garettiana Craib has been investigated as an ingredient in Thai traditional medicine for anti-HIV protease, but there is no report on its antibacterial and anti-inflammatory activities. The objectives of this study were to investigate the anti-inflammatory and antibacterial activities, time-kill profile, and main active constituents of an ethanolic extract of C. garettiana heartwood. The study followed the generally accepted experimental design. All tests were investigated in triplicate. The heartwood of C. garettiana was extracted by maceration with 95% EtOH. The antibacterial activity of the extract and its chemical constituents were determined by their MIC values using resazurin as an indicator. Time-kill profile was determined at 0, 2, 4, 6, 8, 10, 12, and 24 hrs and expressed as log CFU/mL. The anti-inflammatory activity of the extract and its chemical components was investigated by their inhibiting effect on IL-6 and TNF-α production by ELISA. The ethanolic extract was analyzed for its chemical constituents by HPLC technique. The ethanolic extract showed both dose- and time-dependent bactericidal effects against Staphylococcus aureus, methicillin-resistance Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Salmonella Typhi, Salmonella Typhimurium, Klebsiella pneumoniae, and Shigella dysenteriae with MIC values of 312.5, 312.5, 312.5, 1,250, 2,500, 625, 625, 2,500, and 625 µg/mL, respectively. It showed an inhibiting effect on IL-6 production at concentrations of 12.5 to 100 µg/mL. The main active chemical constituent of C. garettiana was piceatannol that showed antibacterial activity against all test bacteria except P. aeruginosa. C. garettiana showed a broad spectrum of antibacterial activity against both Gram-negative and Gram-positive bacteria. Piceatannol and resveratrol from the plant strongly inhibited IL-6 production. Based on these results, we concluded that the ethanolic extract of C. garettiana showed both an antibacterial activity and inhibition of IL-6. Piceatannol is the active constituent of the extract and showed anti-inflammatory and antibacterial activities against Gram-negative and Gram-positive bacteria.

In Vitro and In Vivo Anti-Inflammatory Activities of Benjakul: A Potential Medicinal Product from Thai Traditional Medicine.

Benjakul (BJK) is a Thai traditional remedy consisting of five plants: Piper chaba Hunt., Piper sarmentosum Roxb., Piper interruptum Opiz., Plumbago indica Linn., and Zingiber officinale Roscoe. It is used as a first-line drug to balance patient's symptoms before other treatments. BJK ethanolic extract has been reported to show anti-inflammatory activity through various mediators, e.g., nitric oxide, TNF-α, IL-1ß, and IL-6. Therefore, BJK could serve as a potential novel anti-inflammatory herbal medicine. However, studies on prostaglandin E2 (PGE2), one of the key mediators in acute inflammation, and anti-inflammation in animal models (in vivo) have not been done. This study investigated the anti-inflammatory activity of BJK extract and some of its chemical compounds against PGE2 production in murine macrophage (RAW 264.7) cell line and two in vivo models of anti-inflammatory studies. Ethanolic extract of BJK (BJK[E]) showed high inhibitory activity against PGE2 production with an IC50 value of 5.82 ± 0.10 µg/mL but its water extract (BJK[W]) was inactive. Two chemicals from BJK[E], i.e., plumbagin and myristicin, which served as biological markers, showed strong activity with IC50 values of 0.08 ± 0.01 and 1.80 ± 0.06 µg/mL, respectively. BJK[E] was administered both topically and orally to rats inhibited with inflammation induced by ethyl phenylpropiolate (rat ear edema model) and carrageenan (hind paw edema model). Moreover, the biological activity of BJK extract did not reduce after six-month storage under accelerated condition (40°C, 75% RH). This indicated its stability and a 24-month shelf-life under normal condition. These results supported not only the use of BJK in Thai traditional medicine but also the possibility of further development of phytopharmaceutical products from BJK.

The role of Piper chaba Hunt. and its pure compound, piperine, on TRPV1 activation and adjuvant effect.

BACKGROUND: Piper chaba Hunt. is used as an ingredient in Thai traditional preparation for arthritis. Its isolated compound is piperine which shows anti-inflammatory activity. Piperine produces a burning sensation because it activates TRPV1 receptor. The TRPV1 activation involved with the analgesic and adjuvant effect. P. chaba Hunt. has not been reported about TRPV1 activation and adjuvant effect. The aim of this study was to investigate the effect of P. chaba extract and piperine on TRPV1 receptor, which is considered as a target for analgesic and their adjuvant effects to support the development of an analgesic drug from herbal medicine. METHODS: The effect of P. chaba extract and piperine on HEK cells expressing TRPV1 channel was examined by calcium imaging assay. Adjuvant effects of P. chaba extract and piperine were investigated by a fluorescein isothiocyanate (FITC)-induced contact hypersensitivity (CHS) model in mice. RESULTS: P. chaba extract induced calcium influx with EC50 value of 0.67 µg/ml. Piperine induced calcium influx with EC50 value of 0.31 µg/ml or 1.08 µM. For mouse CHS model, we found that 1% piperine, 5% piperine, 1% P. chaba extract and 5% P. chaba extract significantly enhanced sensitization to FITC as revealed by ear swelling responses. CONCLUSION: P. chaba extract and piperine activated TRPV1 channel and enhanced contact sensitization to FITC.

Antimicrobial Activities of Thai Traditional Remedy "Kheaw-Hom" and Its Plant Ingredients for Skin Infection Treatment in Chickenpox.

Background: Kheaw-Hom is a Thai traditional remedy which appears in the National List of Essential Medicines 2011. This remedy consists of eighteen Thai medicinal plants. It has long been used in folk medicine to treat fever, measles, chickenpox and skin infection, but there has been no scientific report on antimicrobial activities of this remedy. Objective: To investigate antimicrobial activities of Kheaw-Hom remedy extracts and its plant ingredients. Material and Method: Kheaw-Hom remedy and each of its plant ingredients were extracted by maceration in 95% ethanol and decoction in water to obtain ethanolic extract and aqueous extract, respectively. All extracts were tested for antimicrobial activities by microtiter plate-based assay to determine the minimum inhibitory concentration (MIC) and the minimum microbicidal concentration (MMC) values against Staphylococcus aureus (ATCC 25923), methicillin-resistant Staphylococcus aureus (DMST 20651), Staphylococcus epidermidis (ATCC 12228) and Candida albicans (ATCC 90028). Results: The ethanolic extract of Kheaw-Hom remedy showed antimicrobial activities against Staphylococcus aureus, methicillinresistant Staphylococcus aureus and Staphylococcus epidermidis with MIC values of 0.625, 0.625 and 1.25 mg/ml, respectively and MMC values of 1.25, 0.625 and 2.5 mg/ml, respectively. Among all the ethanolic extracts of its plant ingredients, that of Mammea siamensis showed the highest activity with MIC values of 0.005, 0.005 and 0.039 mg/ml and MMC values of 0.005, 0.005 and 0.039 mg/ml, respectively. The weak activity against bacteria was found in the aqueous extract of some plant ingredients. The ethanolic and aqueous extracts of Kheaw-Hom remedy and the aqueous extract of its plant ingredients had no activity against C. albicans but the ethanolic extract of Sophora exigua showed the highest activities against Candida albicans with MIC values of 0.625 mg/ml and MMC values of 0.625 mg/ml. Conclusion: The ethanolic extracts of Kheaw-Hom remedy had antimicrobial activity against S. aureus, methicillin-resistant S. aureus and S. epidermidis that are causes of skin infection from chickenpox. These results support the use of Kheaw-Hom remedy for skin infection treatment in chickenpox.

Antimicrobial Activities of Medicinal Plants Mostly used for Acute Pharyngitis Treatment.

Background: Many people suffer from acute pharyngitis which is caused by bacteria, especially Streptococcus pyogenes. Patients consume antibiotics even though antibiotic drugs have been causing adverse effects. Ten Thai medicinal plant species commonly used for treating acute pharyngitis may reduce the use of antibiotics. Objective: To determine the antimicrobial activity of ten Thai medicinal plant species most commonly used for acute pharyngitis. Material and Method: Plant materials were extracted with 95% ethanol or distilled water then concentrated and dried. Antimicrobial activity of ten Thai medicinal plant species were determined using two standard assays, broth dilution method for minimal inhibitory concentration value (MIC) and agar dilution method for minimal bactericidal concentration value (MBC), against microorganisms that cause acute pharyngitis. Results: The ethanolic extract of Garcinia mangostana showed the strongest activity of both assays, MIC value in range of 0.6-9.8 µg/ml and MBC value in range of 1.2-625 µg/ml, which inhibited all the bacteria tested and particularly inhibited S. pyogenes ATCC 19615 as the most common cause of acute pharyngitis with the value of MIC and MBC at 0.6 and 1.2 µg/ml, respectively. The second highest antimicrobial activity was the ethanolic extract of Glycyrrhiza glabra with MIC value in range of 39-156 µg/ml and MBC value in range of 78-312 µg/ml and it showed strong activity against S. pyogenes ATCC 19615, S. pneumoniae ATCC 49619 and S. mutans ATCC 25175 with the value of MIC and MBC at 39 and 78 µg/ml, respectively. Conclusion: The ethanolic extract of G. mangostana and G. glabra are the two best choice for acute pharyngitis treatment.

Antimicrobial activity of extracts from a Thai traditional remedy called Kabpi for oral and throat infection and its plant components.

BACKGROUND: Thai traditional remedy called Kabpi (KP) has long been usedfor oral and throat infection. It composed with four herbs Syzygium aromaticum (L.) Merr etPerry, Nigella sativa L., Limonia acidissima L. andAchasma sphaerocephalum Holtt. OBJECTIVE: To investigate antimicrobial activity ofKP remedy extracts and its plant components. MATERIAL AND METHOD: The extract procedures were maceration method with 95% ethanol, 50% ethanol and dried by evaporator and boiling in water, filtrated dried by lyophilizer The residue from the maceration in 95% ethanol and 50% ethanol were boiled in water and dried by lyophilizer In the preliminary studied, all extracts were evaluated antimicrobial activity by disc diffusion method. All extracts were tested against one type of gram positive bacteria Staphylococcus aureus (ATCC 25923) and one type ofyeast Candida albicans (ATCC 90028). The active plant extracts were diluted to determine the minimum inhibitory concentration (MIC) values by microtiter plate-based assay. RESULTS: The 95% ethanol extract of KP remedy showed antimicrobial activity against S. aureus (ATCC 25923) and C. albicans (ATCC 90028) (MIC = 0.625, 0.625 mg/ml, respectively). The zone of inhibition ofall extracts were in the range of 7.33 to 23.33 mm. The 95% ethanol extract ofAchasma sphaerocephalum Holtt. showed the highest inhibition zone against S. aureus 21.00 mm (MIC = 0.625 mg/ml). The 95% ethanol extract ofSyzygium aromaticum (L.) Merr etPerry exhibited the best antimicrobial activity against C. albicans the inhibition zone with inhibition zone of23.33 mm (MIC = 0.156 mg/ml). CONCLUSION: The present study demonstrated that the extracts ofKP remedy and its plant components had an antimicrobial effect against oral and throat infection such as S. aureus and C. albicans. These results support using this remedy of Thai traditional medicine called Kabpifor oral and throat infection.

Biological activities and chemical content of Sung Yod rice bran oil extracted by expression and soxhlet extraction methods.

BACKGROUND: Sung Yod rice is a red-violet pigmented rice and grown in the southern part of Thailand. Its rice bran oil has attracted the attention ofscientists who have described anti-oxidant properties ofsome ingredients in Sung Yod rice bran oil. Normally, extraction methods ofcommercial product from rice bran oil are by expression or soxhlet extraction with hexane. Thus, biological activities of Sung Yod rice bran oil related to health and chemical content ofrice bran oilfrom the two methods should be studied. OBJECTIVE: The objectives of this research were to investigate for biological activities and chemical content ofSung Yod rice bran oil obtainedfrom expression or soxhlet extraction method. MATERIAL AND METHOD: Biological activities such as cytotoxic, anti-inflammatory and antioxidant activities were investigated. Sulphorhodamine (SRB) assay was used to test cytotoxic activity against four human cancer cell lines: lung (COR-L23), cervical (HeLa), prostate (PC-3) and breast (MCF-7) and normal human lung cells (MRC-5). The inhibitory effect on lipopolysaccharide (LPS) induced nitric oxide (NO) production in RA W264. 7 cell lines was usedfor the determination of anti-inflammatory effect. DPPH, TEAC and FRAP assay were carried outfor antioxidant activity. Total phenolic compound was determined by Folin-Ciocalteu reagent. y-oryzanol and vitamin E content were determined by HPLC. Sung Yod rice bran oil was produced by expression method (EX) or by soxhlet extraction method using hexane (SXH-I). RESULTS: The percentage ofyield ofSung Yod rice bran oil by EX and SXH were 2.16 and 15.23 %w/w, respectively. Only EX showed the selective cytotoxicity against prostate cancer cells (PC-3), (IC50 = 52.06±1.60 µg/ml). It also exhibited high inhibitory effects on NO production (IC50 = 30.09 µg/ml). In contrast, SXH had no anti-inflammatory effect and cytotoxic activity against any of the cancer cells. EXshowed higher antioxidant activity determined using DPPH compared to SXH. It also showed higher amount of yoryzanol and vitamin E than that ofSXH (3.09±1.04 and 1.35±1.56 mg % w/w ofextracts, respectively). Yet, SXH exhibited higher antioxidant power determined by FRAP assay and higher total phenolic content compared with EX CONCLUSION: Sung Yod rice bran oil, produced by expression method, had better benefit for health regarding cytotoxicity against prostate cancer cells (PC-3), anti-inflammatory effect and antioxidant (using DPPH) than that produced by soxhlet method extracted with hexane.

Effect of Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. on natural killer cell activity and lymphocyte proliferation.

BACKGROUND: Immune system is the most important system ofhuman body. Thaifolk doctors have used some medicinal plants as an adaptogenic drug or immunomodulatory agent. Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. are used by folk doctors to activate immune response in cancer patients. OBJECTIVE: To investigate the effect on natural killer cell activity and on lymphocyte proliferation activity of water extract of P chaba Hunter P. sarmentosum Roxb. and P interruptum Opiz. MATERIAL ANDMETHOD: Plant materials were extracted by decoction method. All extracts were testedfor an immunomodulatory effect using PBMCs from twelve healthy donors by chromium release assay. Lymphocyte proliferation was also determined by 3H-thymidine uptake assay. The degree of activation was expressed as the stimulation index. RESULTS: The water extract of P chaba Hunter significantly increased lymphocyte proliferation at concentrations ofl ng/ml, 10 ng/ml, 1 µg/ml, 5 µg/ml, 10 µg/ml and 100 µg/ml. P sarmentosum Roxb., and P interruptum Opiz. extracts at those concentrations significantly stimulated lymphocyteproliferation. P sarmentosum Roxb. extractsignificantly increased natural killer (NK) cell activity at a concentration of 100 µg/ml but P chaba Hunter and P interruptum Opiz. extracts did not significantly stimulate natural killer cell activity. CONCLUSION: P chaba Hunter, P interruptum Opiz. andP sarmentosum Roxb. have an immunomodulatory effect especially for P sarmentosum Roxb. extract which can activate both lymphocyte proliferation and NK cell activity.

Immunomodulatory activity of Dioscorea membranacea Pierre rhizomes and of its main active constituent Dioscorealide B.

BACKGROUND: The rhizomes of Dioscorea membranacea Pierre, also called Hua-Khao-Yen by Thai name, are used as ingredients in many Thai traditional medicines for the alternative or complementary treatment of cancer and AIDs. Preliminary in vitro studies have indicated that D. membranacea extracts exhibited high cytotoxic activity with several cancer cell lines, but the underlining mechanisms are far from clear. The aims of this study were to investigate the effects of ethanolic and aqueous crude extracts from D. membranacea Pierre, and pure compound from D. membranacea Pierre, Dioscorealide B, on natural killer cells activity and on lymphocyte proliferation. METHODS: Immunomodulatory activity was investigated using PBMCs from healthy donors. NK cells activity was performed by the chromium release assay using PBMCs as effector cells, and K562 cells line labelled with chromium as target cells. Lymphocyte proliferation was determined by 3H-thymidine uptake. The degree of activation was expressed as the stimulation index. RESULTS: The crude ethanolic extracts of D. membranacea Pierre significantly stimulated NK cells activity against K562 cells line at lower concentrations of 10 and 100 ng/ml, but not at higher concentrations. The ethanolic extracts showed no observable effect on lymphocyte proliferation. The crude water extracts significantly increased NK cell activity at concentrations of 10 ng/ml, 100 ng/ml, 1 µg/ml, 10 µg/ml and 100 µg/ml, and also activated lymphocyte proliferation at concentration of 1 ng/ml, 10 ng/ml, 100 ng/ml, 1 µg/ml, 5 µg/ml, 10 µg/ml and 100 µg/ml. However, Dioscorealide B had no significant effect at lower concentrations (0-1 µg/ml and 0-0.1 µg/ml, respectively) on NK cell activity and lymphocyte proliferation. In fact higher concentrations (>10 µg/ml and >0.5 µg/ml) of Dioscorealide B cause a significant decrease in NK cell activity and lymphocyte proliferation. CONCLUSIONS: D. membranacea Pierre stimulated NK cells activity and lymphocyte proliferation, but Dioscorealide B either had no effect, and at higher concentrations decreased NK cell activity and lymphocyte proliferation. Our results suggest that both extracts of D. membranacea Pierre significantly increases immune function, but the underlining mechanism is not clearly understood.

An in vitro inhibitory effect on RAW 264.7 cells by anti-inflammatory compounds from Smilax corbularia Kunth.

BACKGROUND: Smilax corbularia is a Thai medicinal plant locally known as 'Hua-Khao-Yen Neua', which is used for treating inflammatory conditions. OBJECTIVE: To evaluate the anti-inflammatory effect of S. corbularia extracts and its isolated compounds by determination of inhibitory effects on lipopolysaccharide-stimulated PGE2 release, and TNF-alpha and NO production from RAW 264.7 cells. METHODS: The inhibitory effect of aqueous and ethanolic extracts of this plant were determined on LPS-induced NO production, TNF-alpha and PGE2 release in RAW 264.7 cells, as an in vitro indication of possible anti-inflammatory activity. The compounds from active extract were isolated by bioassay-guided fractionation. RESULTS: Only the ethanolic extract of this plant inhibited TNF-alpha and NO production, with IC50 values of 61.97, and 83.90 microg/ml respectively. Three flavonols, engeletin, astilbin and quercetin were isolated from the ethanolic extract. quercetin possessed the highest inhibitory effect on NO production with IC50 11.2 microg/ml (37.1 microM), whereas engeletin and astilbin had no activity (IC50 >100 microg/ml). All three flavonols possessed potent inhibition of PGE2 release with IC50 values of 14.4, 19.6 and 19.9 microg/ml (33.2, 43.5 and 65.8 microM) respectively. Quercetin also exhibited the highest inhibitory effect on TNF-alpha production (IC50 = 1.25 microg/ml or 4.14 microM), but engeletin and astilbin had no activity. CONCLUSION: This is the first report of isolated compounds from S. corbularia with potential anti-inflammatory effects, and the results support the use of this plant by Thai traditional doctors for treatment of inflammatory diseases.

Antimicrobial, antioxidant activities and total phenolic content of Thai medicinal plants used to treat HIV patients.

BACKGROUND: Opportunistic infections in AIDs patients is the leading cause of death in among them. HIV infection was reported as causes of increasing oxidative stress which may lead to progress of many syndrome. Thus medicinal plants as demonstrated antimicrobial and antioxidant activities would be therapeutic values to treat opportunistic infections of AIDs patients. OBJECTIVE: To investigate antibacterial, antioxidant activities and total phenolic contents of five Thai medicinal plants using by Thai traditional doctors to treat opportunistic infections of AIDs patients such as Dioscorea bulbifera L. (DB), Momordica charantia L. (MC), Caricapapaya L. (female and male trees, CPF and CPM) and Phyllanthus amarus Schum & Thonn. (PA). MATERIAL AND METHOD: The ethanolic and water extracts of those herbs were tested. For antioxidant method was measured using DPPH radical scavenging assay, anti-microbial activity using disc diffusion assay and minimal inhibitory concentration (MIC) was determined by using the modified resazurin assay against four species of micro-organisms: Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Candida albicans. Total phenolic content was determined by Folin-Ciocalteau colorimetric method. RESULTS: For water extract of PA showed the highest antibacterial activity against S. aureus (MIC value = 0.625 mg/ml). The ethanolic extract of MC showed the highest activity against B. subtilis (MIC = 0.625 mg/ml). Only ethanolic extract of DB inhibited growth of E. coli (MIC = 5 mg/ml) it also inhibited growth of gram positive bacteria such as S. aureus and B. subtilis with the same MIC values (2.5 mg/ml). No plant extracts showed activity against C. albicans. The ethanolic extract of CPM, PA and DB and the water extract of PA showed high antioxidant activity (EC50 of 8.48, 9.54, 11.07 and 11.37 microg/ml, respectively). The water extract of PA and the ethanolic extract of DB, CPM showed high total phenolic content of 262.54, 106.26 and 83.78 mg/g, respectively. The total phenolic content of these extracts correlated with DPPH radical scavenging activity, while only ethanolic extract of PA showed high antioxidant activity (9.54 microg/ml) but it contain low phenolic content (45.50 mg/g). CONCLUSION: Our findings support the usage of the these plants to treat opportunistic infection of Thai traditional doctors in AIDs patients. Thus, it is recommended that the isolation of pure active antibacterial and antioxidant from these plant extracts should be carried on.

Antimicrobial activity of Thai medicinal preparation of Khampramong Temple used for cancer treatment and its plant components.

BACKGROUND: Thai medicinal preparation of Khampramong Temple has been used for cancer treatment more than ten years ago. It is composed of eleven herbs. Many anticancer drugs exhibited antimicrobial activity as antitumor antibiotics such as the anthracycline group [daunorubicin] and quinone group [mitomycin C]. OBJECTIVE: To determine antimicrobial activity of Thai medicinal plants used to treat cancer patients of Khampramong Temple by disc diffusion and agar dilution methods. MATERIAL AND METHOD: The extraction procedure was maceration method using 95% ethanol and drying by evaporator In the preliminary study, all extracts were evaluated for antimicrobial activity by disc diffusion method against two strains of Gram positive bacteria (Staphylococus aureus and Bacillus subtilis), one Gram negative bacteria (Escherichia coli) and one fungus (Candida albicans). The active plant extracts were diluted to determine the minimum inhibitory concentration (MIC) by agar dilution method. RESULTS: The preparation showed antimicrobial activity against S. aureus, B. subtilis and E. coli (MIC = 1.25, 0.625 and 5 mg/ml, respectively) but no inhibition against Candida albicans. Most extracts showed activity against B. subtilis and Rhinacanthus nasutus extract showed the highest antimicrobial activity (MIC = 0.156 mg/ml). Hydnophytum formicarum Jack, Tectona grandis L.f and Salacia chinensis L. exhibited good antibacterial activity against S. aureus (MIC = 1.25, 0.15625 and 0.3125 mg/ml respectively). CONCLUSION: These results supported the use of this preparation on chronic wound infection of cancer patients and the antimicrobial compounds of the preparation should be further studied to be used in cancer patients.