Evaluation of Biological Activity of Mastic Extracts Based on Chemotherapeutic Indices.

BACKGROUND: Most previous mastic investigators have not considered its potent cytotoxicity that may significantly affect the interpretation of obtained data. In the present study, we re-evaluated several biological activities of mastic extracts, based on chemotherapeutic indexes. MATERIALS AND METHODS: Pulverized mastic gum was extracted with n-hexane and then with ethyl acetate or independently with methanol or n-butanol. Tumor specificity (TS) of the extracts was determined by their cytotoxicity against human malignant and non-malignant cells. Antibacterial activity was determined by their cytotoxicity against bacteria and normal oral cells. Antiviral activity was determined by their protection of viral infection and cytotoxic activity. Cytochrome P-450 (CYP) 3A4 activity was measured by ß-hydroxylation of testosterone. RESULTS: Ethyl acetate extract showed slightly higher tumor specificity (TS=2.6) and one order higher antibacterial activity (selectivity index (SI)=0.813) than other extracts (TS=1.4-2.5; SI=0.030-0.063). All extracts showed no anti-human immunodeficiency virus (HIV) activity, but some anti-herpes simplex virus (HSV) activity, which was masked by potent cytotoxicity. They showed strong inhibitory activity against CYP3A4. CONCLUSION: Ethyl acetate extraction following the removal of cytotoxic and CYP3A4 inhibitory substances by n-hexane can enhance antitumor and antibacterial activity of mastic.

Antiviral and Antitumor Activity of Licorice Root Extracts.

BACKGROUND: In the search for anti-viral and antitumor substances from natural resources, antiviral and antitumor activities of licorice root extract and purified ingredients were investigated. MATERIALS AND METHODS: Viability of cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Antiviral activity was quantified by the selectivity index, defined as the ratio of the 50% cytotoxic concentration (CC50) to the 50% effective concentration against human immunodeficiency virus (HIV) or herpes simplex virus (HSV)-infected cells (EC50). The tumor specificity was calculated by the ratio of CC50 against human normal oral cells to that against human oral squamous cell carcinoma cell lines. Licorice flavonoids and lower molecular polyphenols were subjected to quantitative structure-activity relationship analysis. RESULTS: Alkaline extract of licorice root had higher anti-HIV activity than did water extracts, confirming our previous reports. On the other hand, water extract, especially the flavonoid-rich fraction, had higher anti-HSV activity than did the alkaline extract. The flavonoid-rich fraction was more cytotoxic against human oral squamous cell carcinoma cell lines compared to normal oral cells, suggesting their tumor-specific cytotoxicity. CONCLUSION: The present study suggests that water and alkaline extracts of licorice root exert different mechanisms of actions against these two viruses. Physicochemical properties, rather than the category of compounds, may be important in determining their anti-HSV activity.

Synergism of Alkaline Extract of the Leaves of Sasa senanensis Rehder and Antiviral Agents.

BACKGROUND: Previous studies have shown a much greater antiviral activity of alkaline extract of the leaves of Sasa senanensis Rehder (SE) against human immunodeficiency virus (HIV), compared to lignin precursors, tannins and flavonoids, suggesting its possible application to oral diseases. Systematic comparative study with herpes simplex virus (HSV) has been limited compared to that with HIV. In the present study, we investigated whether combination of SE with other popular antiviral agents further enhances their individual activity. MATERIALS AND METHODS: Cell viability of mock-infected, HIV-infected and HSV-infected cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The antiviral activity was evaluated by the selectivity index, defined as the ratio of 50% cytotoxic concentration to 50% effective concentration. Synergy between SE and antiviral agents was evaluated by MacSynerg and CompuSyn software. RESULTS: SE showed potent anti-HIV activity, although its activity was two-orders lower than that of azidothymidine, 2',3'-dideoxycytidine dextran sulfate and curdlan sulfate. Combination of SE with these antiviral agents produced synergistic effects. Using a newly established MTT assay system for anti-HSV activity, SE and acyclovir were found to have synergistic anti-HSV activity. CONCLUSION: The present study suggests the possible efficacy of the clinical application of SE combined with antiviral agents.

Efficient utilization of licorice root by alkaline extraction.

Compared to studies of water extracts of plants, those utilising alkaline extracts are limited. Both water and alkaline extracts from licorice root were compared regarding their biological activities. Licorice root was successively extracted first with water or alkaline solution (pH 9 or 12), and the alkaline (pH 12.0) extract was further separated into 50% ethanol-soluble and -insoluble fractions. Viable cell number was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Antibacterial activity against Porphyromonas gingivalis 381 was determined by turbidity assay. Cytochrome P-450 (CYP)3A4 activity was measured by ß-hydroxylation of testosterone using human recombinant CYP3A4. Radical intensity of superoxide and hydroxyl radicals was determined by electron spin resonance spectroscopy. Alkaline extraction yielded slightly higher amounts of dried materials compared to water extraction. Alkaline extract showed higher anti-HIV and antibacterial activities, and similar magnitudes of CYP3A4 inhibitory and superoxide and hydroxyl radical-scavenging activities, compared to water extract. When alkaline extract was fractionated by 50% ethanol, anti-HIV activity was recovered from the insoluble fraction representing approximately 3% of the alkaline extract, whereas antibacterial activity was concentrated in the soluble fraction rich in glycyrrhizid acid, flavanones and chalcones. All extracts and sub-fractions led to bimodal hormetic dose-response (maximum hormetic response=238%) on the bacterial growth. The present study demonstrated the superiority of alkaline extraction over water extraction for preparing anti-HIV and antibacterial agents at higher yield from licorice root.

Biological interaction between Sasa senanensis Rehder leaf extract and toothpaste ingredients.

BACKGROUND: Previous studies have shown antiviral, antibacterial, and anti-inflammatory activity of alkaline extract of the leaves of Sasa senanensis Rehder (SE). In order to manufacture an SE-containing toothpaste for combating oral diseases, we investigated the possible interaction between the candidate ingredients of toothpaste: SE, isopropyl methylphenol (IPMP, antibacterial agent) and charcoal prepared from Sasa senanensis Rehder. MATERIALS AND METHODS: Cell viability of mock-infected, HIV-infected and UV-irradiated cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Superoxide radical scavenging activity was determined by electron-spin resonance spectroscopy. Antibacterial activity against Porphyromonas gingivalis 381 and Streptococcus mutans ATCC25175 was determined by the turbidity assay. RESULTS: Exposure to less than 50% SE or less than 0.31 mM IPMP for 10 min scarcely damaged human cultured gingival and periodontal ligament fibroblasts. Both SE and IPMP showed bi-modal action, stimulating the bacterial growth at lower concentrations, but synergistically inhibiting it at higher concentrations. Addition of extremely high concentrations of charcoal enhanced both anti-HIV and anti-UV activity of SE. CONCLUSION: Practically, addition of charcoal may not be recommendable, since one or two orders higher concentrations of charcoal as compared with SE, are required to achieve the synergistic effect for anti-HIV and anti-UV activity. Rather, addition of about one tenth of the amount of IPMP may be recommendable for enhancing the antibacterial activity.

Anti-UV/HIV activity of Kampo medicines and constituent plant extracts.

AIM: In order to search for new biological activities of Kampo medicines and their constituent plant extracts, we investigated whether they protect the cells from the cytotoxicity induced by UV irradiation and human immunodeficiency virus (HIV) infection. MATERIALS AND METHODS: Anti-UV/HIV activity (SI value) was evaluated as the ratio of the CC(50) (concentration that reduced the viable cell number by 50%) to the EC(50) (the concentration that increased the viability of UV-irradiated or HIV-infected cells to 50%): SI=CC(50)/EC(50). The content of glycyrrhizin in each sample was determined by high performance liquid chromatography (HPLC). Caspase-3/-7 activity was assayed by cleavage of poly ADP ribose polymerase using western blot analysis. RESULTS: Among 25 plant extracts, Gardenia fruit had the highest anti-UV activity (SI≥8.0), followed by Glycyrrhiza (SI=4.3), Coptis rhizoma (SI=1.5), Cimicifuga rhizoma (SI>1.4), Saposhnikovia root (SI>1.3) and Japanese Gentian (SI>1.1). Among ten Kampo medicines, Unseiin and Hangesyashinto (SI>4.9) had the highest anti-UV activity, followed by Shosaikoto (SI>4.3), Saireito (SI>3.4), Rikkosan (SI>1.2) and Kikyoto (SI=1.1). Glycyrrhiza inhibited UV-induced caspase-3/-7 activation. Only Polyporus sclerotium (SI>4.4), Gardenia fruit (SI>2.7), Atractylodes lancea rhizoma (SI>1.9), Cnidium rhizoma (SI>1.5) and Japanese Angelica root (SI>1.1) exhibited some anti-HIV activity. There was no apparent correlation of their anti-UV/HIV activity and content of glycyrrhizin, a major component of Glycyrrhiza, which exhibited much higher anti-UV activity (SI=20.6) and some anti-HIV activity (SI>2.0). CONCLUSION: The present study suggests the involvement of substances other than glycyrrhizin in the anti-UV/HIV activity of Kampo medicines and their constituent plant extracts.

Biological activity of SE-10, granulated powder of Sasa senanensis Rehder leaf extract.

BACKGROUND: We have previously reported that alkaline extract of Sasa senanensis leaves (SE) showed potent anti-HIV, anti-UV and radical scavenging activity. In the present study, we investigated the biological activities of SE-10, a granulated powder of SE supplemented with lactose, lactitol, trehalose and tea extract. MATERIALS AND METHODS: Cell viability of mock-infected, HIV-infected, and UV-irradiated cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Scavenging activity of superoxide anion and hydroxyl radicals was determined by electron-spin resonance spectroscopy. Cytochrome P-450 (CYP)3A4 activity was measured by ß-hydroxylation of testosterone in human recombinant CYP3A4. RESULTS: SE-10 had slightly higher anti-HIV and anti-UV activities, but slightly lower radical-scavenging and CYP3A4-inhibitory activities, as compared with SE. CONCLUSION: The present study demonstrates that the biological activities of SE were well preserved during the manufacturing process of SE-10.

Comparative study of biological activity of three commercial products of Sasa senanensis Rehder leaf extract.

BACKGROUND: We have previously reported that alkaline extract of Sasa senanensis leaves (SE) has several biological activities characteristic of lignin-carbohydrate complex (LCC). In the present study, we compared the biological activity of three commercially available products of SE (products A, B and C). MATERIALS AND METHODS: Cell viability of mock-infected, HIV-infected, UV-irradiated cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Radical intensity was determined by electron spin resonance spectroscopy. Cytochrome P-450 (CYP)3A4 activity was measured by ß-hydroxylation of testosterone in human recombinant CYP3A4. RESULTS: Product A is a pure SE that contains Fe(II)-chlorophyllin, whereas products B and C contain Cu(II)-chlorophyllin and less LCC. Product C is supplemented with ginseng and pine (Pinus densiflora) leaf extracts. Product A exhibited 5-fold higher anti-HIV, 4-fold higher anti-UV, 5-fold higher hydroxyl radical-scavenging, and 3-fold lower CYP3A4 inhibitory activities as compared to those of product B, and 5-fold higher, 1.5-fold higher, comparable, and 7-fold lower activities, respectively, as compared to those of product C. CONCLUSION: The present study demonstrates for the first time the superiority of product A over products B and C, suggesting the beneficial role of LCC and Fe(II)-chlorophyllin.

Biological activity of luteolin glycosides and tricin from Sasa senanensis Rehder.

BACKGROUND: In contrast to the several reports of alkaline extracts (Sasa-health, SE), no study of flavonoids from the leaves of S. senanensis has been reported. Four flavonoids were isolated from this plant species and their biological activities were investigated. MATERIALS AND METHODS: Luteolin 6-C-ß-D-glucoside [1], luteolin 7-O-ß-D-glucoside [2], luteolin 6-C-α-L-arabinoside [3] and tricin [4] were extracted from the leaf of S. senanensis with methanol, partitioned with ethyl acetate, separated by Sephadex LH-20 and purified by high-performance liquid chromatography (HPLC). The structure was determined by ultraviolet (UV) spectra, high-resolution mass spectra (HR-MS) and nuclear magnetic resonance (NMR). RESULTS: The luteolin glycosides, 1-3 showed no cytotoxicity against the human normal oral cells and oral squamous cell carcinoma cell lines used up to 0.8 mg/ml, whereas 4 was highly cytotoxic. The luteolin glycosides 1-3 protected the cells from UV induced cytotoxicity, more efficiently than 4. The anti-HIV activity of 4 (Selectivity index, SI=27) was much higher than that of the luteolin glycosides (SI=2-7), but lower than that of SE (SI=40). The scavenging activity of 1-3 against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radicals was comparable with that of quercetin and, much higher than that of 4. CONCLUSION: The luteolin glycosides from S.senanensis show several new biological properties distinct from tricin and the anti-UV activity of the luteolin glycosides may be derived from their radical scavenging activity.

Anti-HIV and immunomodulation activities of cacao mass lignin-carbohydrate complex.

BACKGROUND: Recently, a prominent antiviral and macrophage stimulatory activity of cacao lignin-carbohydrate complex (LCC) has been reported. However, the solubility and sterility of LCC have not been considered yet. In the present study, complete solubilisation and sterilisation was achieved by autoclaving under mild alkaline conditions and the previously reported biological activities were re-examined. MATERIALS AND METHODS: LCCs were obtained by 1% NaOH extraction and acid precipitation, and a repeated extraction-precipitation cycle. Nitric oxide (NO) and cytokine productions were assayed by the Griess method and ELISA, respectively. Inducible NO synthase (iNOS) expression was determined by Western blot analysis. Superoxide anion, hydroxyl radical and nitric oxide radical-scavenging activity was determined by ESR spectroscopy. RESULTS: Cacao mass LCC showed reproducibly higher anti-HIV activity than cacao husk LCC. Cacao mass LCC, up to 62.5 µg/ml, did not stimulate mouse macrophage-like cells (RAW264.7 and J774.1) to produce NO, nor did it induce iNOS protein, in contrast to lipopolysaccharide (LPS). Cacao mass LCC and LPS synergistically stimulated iNOS protein expression, suggesting a different point of action. Cacao mass LCC induced tumour necrosis factor-α production markedly less than LPS, and did not induce interleukin-1ß, interferon-α or interferon-γ. ESR spectroscopy showed that cacao mass LCC, but not LPS, scavenged NO produced from NOC-7. CONCLUSION: This study demonstrated several new biological activities of LCCs distinct from LPS and further confirmed the promising antiviral and immunomodulating activities of LCCs.

Multiple biological complex of alkaline extract of the leaves of Sasa senanensis Rehder.

Previous studies have shown anti-inflammatory potential of alkaline extract of the leaves of Sasa senanensis Rehder (SE). The aim of the present study was to clarity the molecular entity of SE, using various fractionation methods. SE inhibited the production of nitric oxide (NO), but not tumour necrosis factor-α by lipopolysaccharide (LPS)-stimulated mouse macrophage-like cells. Lignin carbohydrate complex prepared from SE inhibited the NO production to a comparable extent with SE, whereas chlorophyllin was more active. On successive extraction with organic solvents, nearly 90% of SE components, including chlorophyllin, were recovered from the aqueous layer. Anti-HIV activity of SE was comparable with that of lignin-carbohydrate complex, and much higher than that of chlorophyllin and n-butanol extract fractions. The CYP3A inhibitory activity of SE was significantly lower than that of grapefruit juice and chlorophyllin. Oral administration of SE slightly reduced the number of oral bacteria. When SE was applied to HPLC, nearly 70% of SE components were eluted as a single peak. These data suggest that multiple components of SE may be associated with each other in the native state or after extraction with alkaline solution.

Antitumor potential of three herbal extracts against human oral squamous cell lines.

Three Chinese herbal extracts of Drynaria baronii, Angelica sinensis and Cornus officinalis Sieb. et Zucc (referred to as DB, AS, CO, respectively) were investigated for their antitumor potential. These extracts showed very weak cytotoxicity against all nine cultured human cells (normal and tumor cells), but with some tumor-specific cytotoxicity displayed by DB and CO. These extracts showed little or no growth stimulation effects at lower concentrations (so-called 'hormetic effect'). Human oral squamous cell carcinoma cell lines (HSC-2, NA) were relatively resistant to committing apoptosis, as compared with human promyelocytic leukemia HL-60 cells. Electron-spin resonance spectroscopy shows that DB and CO scavenged superoxide anion (generated by hypoxanthine and xanthine oxidase reaction) and hydroxyl radical (generated by Fenton reaction) more efficiently than AS. DB and CO, but not AS, produced broad radical peak(s) and enhanced the superoxide scavenging activity of vitamin C. However, none of the extracts clearly enhanced the cytotoxicity of mitoxantrone, an anthracycline antitumor antibiotic. DB, but not CO and AS, showed weak anti-HIV activity. These data demonstrate several unique antitumor properties of DB.

Antiviral, antibacterial and vitamin C-synergized radical-scavenging activity of Sasa senanensis Rehder extract.

Sasa senanensis Rehder extract (SE) showed slightly higher cytotoxicity against human squamous cell carcinoma cell lines and human glioblastoma cell lines, as compared with human oral normal cells (gingival fibroblast, pulp cell, periodontal ligament fibroblast), and was more cytotoxic to human myelogenous and T-cell leukemia cell lines. SE showed a bacteriostatic effect on Fusobacterium nucleatum and Prevotella intermedia, but almost completely eliminated hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) produced by these bacteria. SE protected human T-cell leukemia MT-4 cells from the cytopathic effect of human immunodeficiency virus (HIV) infection, and its anti-HIV activity was much higher than that of tannins and flavonoids, comparable with that of natural and synthetic lignins. SE also protected the MDCK cells from the cytopathic effect of influenza virus infection. SE synergistically enhanced the superoxide anion and hydroxyl radical-scavenging activity of vitamin C. The present study suggests the functionality of SE as a complementary alternative medicine.

Anti-HIV and vitamin C-synergized radical scavenging activity of cacao husk lignin fractions.

Cacao husk lignin fractions, prepared by acid precipitation and 50% ethanol precipitation showed unexpectedly higher anti-human immunodeficiency virus (HIV) activity, as compared with the corresponding fractions from the cacao mass, amounting to the level comparable with that of popular anti-HIV compounds. The cacao husk lignin fractions also showed anti-influenza virus activity, but did not show antibacterial activity. The cacao husk lignin fractions synergistically enhanced the superoxide anion and hydroxyl radical scavenging activity of vitamin C. The cacao husk lignin fractions stimulated nitric oxide generation by mouse macrophage-like cells, to a level higher than that attained by lipopolysaccharide (LPS). The present study suggests the functionality of cacao husk lignin fractions as complementary alternative medicine.

Anti-stress, anti-HIV and vitamin C-synergized radical scavenging activity of mulberry juice fractions.

Anti-stress and anti-HIV activity of mulberry juice were separated by centrifugation. The anti-stress activity was enriched in the supernatant fraction whereas the anti-HIV activity in the precipitate fraction. Oral administration of the supernatant fraction significantly reduced the elevated plasma level of lipid peroxide in mice loaded with water immersion restraint stress. The kinetic study revealed that the anti-stress activity was maintained for 4 hours after cessation of the administration of mulberry juice. The lignin fraction in the precipitate fraction scavenged superoxide and hydroxyl radicals more efficiently than other fractions, in a synergistic fashion with sodium ascorbate. Anti-HIV activity of mulberry juice was concentrated in the lignin fraction, whereas blueberry juice, which has no precipitating fibrous materials, did not show anti-HIV activity. The present study suggests the functionality of mulberry juice as an alternative medicine.

Anti-stress activity of mulberry juice in mice.

The possible anti-stress activity of mulberry juice was investigated in mice. When mice were subjected to water immersion restraint stress at 25 degrees C for 8 h, the plasma lipid peroxide level, determined by the d-ROMs test performed 12 h thereafter, was almost doubled. After administration of mulberry juice one or two weeks before the stress loading, the lipid peroxidation was completely blocked. Administration of mulberry juice after the stress loading, without pre-administration, was also protective. ESR spectroscopy revealed that mulberry juice scavenged superoxide anion (generated by hypoxanthine and xanthine oxidase reaction), hydroxyl radical (produced by the Fenton reaction) and NO radical (generated by a NO donor) at approximately 50% efficiency of blueberry juice. Mulberry juice produced smaller amounts of radical at neutral to alkaline pH. The cytotoxic and anti-HIV activities of mulberry juice were 18% and >4-fold those of blueberry juice, respectively. These data suggest that the anti-stress activity of mulberry juice in vivo may be derived from its radical scavenging activity.

Cytotoxicity and radical modulating activity of Moxa smoke.

The biological activities of Moxa, used as moxibustion, have not been well documented. We investigated here Moxa smoke for its tumor-specific cytotoxicity, anti-HIV activity, radical intensity and radical scavenging activity, in comparison with previously published data of Moxa extract. Moxa smoke showed slightly higher cytotoxicity against human tumor cell lines (oral squamous cell carcinoma HSC-2, HSC-3, promyelocytic leukemia HL-60) than against normal oral cells (gingival fibroblast HGF, pulp cell HPC, periodontal ligament fibroblast HPLF), yielding a tumor specificity index of 1.29. Moxa smoke dose-dependently induced internucleosomal DNA fragmentation, activation of caspases 3, 8 and 9, and slightly modified the expression of apoptosis-related proteins (Bcl-2, Bad, Bax) in HL-60 cells, but to much lesser extents than attained by positive controls (UV irradiation, actinomycin D treatment). ESR spectroscopy showed that Moxa smoke generated semiquinone-type radicals under alkaline conditions, and scavenged O2(-), hydroxyl radical, singlet oxygen and NO. All Moxa smoke preparations showed no apparent anti-HIV activity. These data demonstrate the antitumor potential of Moxa smoke.