Cumin – In stomach and cervical cancer – In the present study, cancer chemopreventive potentials of different doses of a cumin seed-mixed diet were evaluated against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis and 3-methylcholanthrene (MCA)-induced uterine cervix tumorigenesis. Results showed a significant inhibition of stomach tumor burden (tumors per mouse) by cumin. Tumor burden was 7.33 +/- 2.10 in the B(a)P-treated control group, whereas it reduced to 3.10 +/- 0.57 (P < 0.001) by a 2.5% dose and 3.11 +/- 0.60 (P <0.001) by a 5% dose of cumin seeds. Cervical carcinoma incidence, compared with the MCA-treated control group (66.67%), reduced to 27.27% (P < 0.05) by a diet of 5% cumin seeds and to 12.50% (P < 0.05) by a diet of 7.5% cumin seeds. The effect of 2.5 and 5% cumin seed-mixed diets was also examined on carcinogen/xenobiotic metabolizing phase I and phase II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH), and lipid peroxidation in the liver of Swiss albino mice. Levels of cytochrome P-450 (cyt P-450) and cytochrome b5 (cyt b(5)) were significantly augmented (P < 0.05) by the 2.5% dose of cumin seed diet. The levels of cyt P-450 reductase and cyt b(5) reductase were increased (significance level being from P < 0.05 to P < 0.01) by both doses of cumin. Among the phase II enzymes, glutathione S-transferase specific activity increased (P < 0.005) by the 5% dose, whereas that of DT-diaphorase increased significantly (P < 0.05) by both doses used (2.5 and 5%). In the antioxidant system, significant elevation of the specific activities of superoxide dismutase (P < 0.01) and catalase (P < 0.05) was observed with the 5% dose of cumin. The activities of glutathione peroxidase and glutathione reductase remained unaltered by both doses of cumin. The level of reduced glutathione measured as nonprotein sulfhydryl content was elevated (significance level being from P < 0.05 to P < 0.01) by both doses of cumin. Lipid peroxidation measured as formation of MDA production showed significant inhibition (P < 0.05 to P < 0.01) by both doses of cumin. LDH activity remained unaltered by both doses of cumin. The results strongly suggest the cancer chemopreventive potentials of cumin seed and could be attributed to its ability to modulate carcinogen metabolism.
Thyme – for Lung diseases – Thyme (Thymus vulgaris) is used traditionally to prepare herbal remedies possessing expectorant, mucolytic, antitussive and antispasmodic properties. The aim of the present study was to investigate the effects of a standardized hydroalcoholic extract of thyme on primary human airway (bronchial/tracheal) epithelial cell lines in a model of lung inflammation induced by LPS. In addition, the effects of thyme extract on human lung cancer cell line (H460) were analysed. Thyme extract showed significant anti-inflammatory properties by reducing the NF-κB p65 and NF-κB p52 transcription factors protein levels followed by the decrease of pro-inflammatory cytokines (IL-1 beta and IL-8), and Muc5ac secretion in human normal bronchial and tracheal epithelial cells. Moreover, the extract showed cytotoxic effects on H460 cancer cells, modulated the release of IL-1 beta, IL-8 and down-regulated NF-κB p65 and NF-κB p52 proteins. Taken together, these results substantiated the traditional uses of thyme in the treatment of respiratory diseases. Thyme extract might be an effective treatment of chronic diseases based on inflammatory processes when hypersecretion of mucus overwhelms the ciliary clearance and obstructs airways, causing morbidity and mortality. Moreover thyme extract, evaluated in H460 lung cancer cell line, demonstrated to induce cell cytotoxicity in addition to reduce inflammatory cell signals.
Thyme instead of metrodiazinole – One of the most common drugs used against a wide variety of anaerobic protozoan parasites is metronidazole.However, this drug is mutagenic for bacteria and is a potent carcinogen for rodents. Thymus vulgaris is used for cough suppression and relief of dyspepsia. Also it has antibacterial and antifungal properties. The aim of this study was to investigate antiamebic effect of Thymus vulgaris against Entamoeba histolytica in comparison with metronidazole. One hundred gram air-dried T. vulgaris plant was obtained and macerated at 25°C for 14 days using n-hexane and a mixture of ethanol and water. For essential oil isolation T. vulgaris was subjected to hydrodistillation using a clevenger-type apparatus for 3 hr. E. histolytica, HM-1: IMSS strain was used in all experiments. It was found that the minimal inhibitory concentration (MIC) for T. vulgaris hydroalcoholic, hexanic extracts, and the essential oil after 24 hr was 4 mg mL-1, 4 mg mL-1, and 0.7 mg mL-1, respectively. After 48 hr the MIC for T. vulgaris hydroalcoholic and hexanic extracts was 3 and 3 mg mL-1, respectively. Therefore, it can be concluded that the Iranian T. vulgaris is effective against the trophozoites of E. histolytica. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/thymus-vulgaris
H Plylori – Among the plants that killed H pylori, turmeric was the most efficient, followed by cumin, ginger, chilli, borage, black caraway, oregano and liquorice. Moreover, extracts of turmeric, borage and parsley were able to inhibit the adhesion of H pylori strains to the stomach sections. Conclusion: Several plants that were tested in our study had bactericidal and/or anti-adhesive effects on H pylori. Ingestion of the plants with anti-adhesive properties could therefore provide a potent alternative therapy for H pylori infection, which overcomes the problem of resistance associated with current antibiotic treatment. https://www.scopus.com/record/display.uri?eid=2-s2.0-31144473388&origin=inward&txGid=a0ca2fae25c1aede56ea8b380af41ddd
Antibacterial and Antifungal Activities of Spices
This review summarizes the scientific studies on the antibacterial and antifungal activities of spices and their derivatives, and some suggestions and prospects are offered for future studies.
Clove (Eugenia caryohyllata), belonging to family Myrtaceae, is widely used in medicine as antiseptic against infectious diseases like periodontal disease due to the antimicrobial activities against oral bacteria . Clove is also commonly applied in food industry as a natural additive or antiseptic to increase shelf-life due to the effective antimicrobial activities against some foodborne pathogens . The main active component of clove oil and extract was found, i.e., eugenol [15,17].
2.1. Antimicrobial Activities of Clove
Antimicrobial activities of clove water extract were studied in vitro and in vivo against pathogenic microorganisms (S. aureus and E. coli, in a model of pyelonephritis) . An in vitro study was conducted with the agar well diffusion method, and the results suggested that clove water extract showed antibacterial activity against S. aureus (minimum inhibitory concentration (MIC): 2 mg/mL) and E. coli (MIC: 2.5 mg/mL). While in vivo, the study was conducted in 40 adult male albino rats, and the results confirmed the efficacy of clove extract as natural antimicrobials. The direct antimicrobial activities of ultra-fine powders of ball-milled cinnamon and clove were tested by Kuang et al.  against E. coli, S. aureus, Brochothrix thermosphacta (B. thermosphacta), Lactobacillus rhamnosus (L. rhamnosus), and Pseudomonas fluorescens (P. fluorescens) from meat, using broth dilution method. Clove powder showed strong inhibitory effects on five microorganisms tested with the MICs ranging from 1.0% w/v (L. rhamnosus and B. thermosphacta ) to 2.0% w/v (P. fluorescens), and the inhibitory effects were positively associated with the concentrations of powder, which increased from 0.5% to 2.5% w/v.
Clove could destroy cell walls and membranes of microorganisms, and permeate the cytoplasmic membranes or enter the cells, then inhibit the normal synthesis of DNA and proteins . Eugenol, the major component of clove, could inhibit the production of amylase and proteases in Bacillus cereus (B. cereus) and has the ability of cell wall deterioration and cell lysis .
2.2. Comparison of Antimicrobial Activities of Clove and Other Spices
Badei et al.  tested the antimicrobial activities of cardamom, cinnamon and clove essential oils (EOs) against nine Gram-positive bacterial strains, four Gram-negative bacterial strains, seven molds, and two yeasts, compared with phenol, using the disc diffusion method. Clove EO showed the highest antimicrobial activity, and the antimicrobial spectra (diameter of inhibition zones) of 10% clove EO was 1.48 times as that of 10% phenol. Schmidt et al.  evaluated the antifungal effects of eugenol-containing EOs of 4 spices on 38 Candida albicans (C. albicans) isolates, of which 12 were isolated from oropharynges, 16 from vaginas, and 10 from damaged skin, using the microdilution method. Clove EO possessed the strongest antifungal activities against all C. albicans strains among the tested spices. Pure eugenol alone exhibited weaker antifungal activities than clove leaf EO. Angienda et al.  investigated the antimicrobial activities of EOs of four spices against Salmonella typhimurium (S. typhimurium), E. coli, B. cereus, and Listeria innocua (L. innocua) by agar diffusion test. Clove EO showed the most effective inhibition against both Gram-positive bacteria and Gram-negative bacteria compared with three other EOs, with the MICs ranging from 1.25% v/v (B. cereus) to 2.50% v/v (S. typhimurium and E. coli). Lomarat et al.  reported the antimicrobial activities of EOs from nine spices against histamine-producing bacteria including Morganella morganii (M. morganii), by determining MICs and minimum bactericidal concentrations (MBCs) using the broth dilution assay, and also found the antibacterial compounds of EOs by bioautography-guided isolation. The results indicated that the clove EO was the most effective against M. morganii among nine tested spices with MIC 0.13% v/v and MBC 0.25% v/v. The eugenol was identified as the active component of clove EO by thin layer chromatography bioautography assay.
Shan et al.  tested the antibacterial activities of ethanol extracts from five spices and herbs against L. monocytogenes, S. aureus, and Salmonella enterica (S. enterica) in raw pork by counting bacterial enumeration. When treated with clove extract, raw pork samples were found with the fewest colonies of tested bacteria. Bayoub et al.  reported the antimicrobial activities of ethanol extracts of 13 plants including clove against L. monocytogenes, the MICs were determined by agar well diffusion test. The results showed that clove extract was the most effective inhibitor against L. monocytogenes compared with the other 12 selected plant ethanol extracts, with the MIC 0.24 mg/mL. Cui et al.  tested the antimicrobial activities of 90 plant extracts (water and 99.5% ethanol extracts) against Clostridium spp. Clove water extract was found with the greatest antimicrobial activity against Clostridium botulinum in trypticase peptone glucose yeast extract broth (pH = 7.0) among all the water extracts, and the MICs of clove extract ranged from 0.1% to 0.2% against Clostridium spp. Antimicrobial effects of 3 extracts (ethyl acetate, acetone, and methanol extracts) of 12 plants were tested on 2 fungi (Kluyveromyces marxianus (K. marxianus) and Rhodotorula rubra (R. rubra)) and 8 bacteria (Klebsiella pneumoniae (K. pneumoniae), Bacillus megaterium (B. megaterium), P. aeruginosa, S. aureus, E. coli, Enterobacter cloacae (E. cloacae), Corynebacterium xerosis (C. xerosis), and Streptococcus faecalis (S. faecalis)) by the disc diffusion method . Clove exhibited the most effective inhibitory impacts. The methanol extract from clove showed inhibition against microorganisms (diameter of inhibition zones (DIZs): 8–24 mm) tested except K. pneumoniae. The acetone extract showed inhibition against microorganisms (DIZs: 8–18 mm) tested except R. rubra and K. pneumoniae. The ethyl acetate extract only showed antibacterial activity against B. megaterium (DIZ: 7 mm). Liang et al.  observed the antimicrobial activities of seven spices, and different concentrations of extracts and EOs in each spice were used to test the effects on the growth of spoilage microorganisms in apple cider by total plate counts. Clove products showed the strongest antimicrobial activities compared with other spices tested. Nearly seven log reduction of microorganisms was observed at 0.8% v/v in the cider for clove oil and 2% w/w for clove powder at room temperature. Badhe et al.  tested the antimicrobial activities of many spice and herb powders against S. aureus, S. typhimurium, E. coli, and B. cereus at refrigerated temperature (8 ± 2 °C) for intervals of 0, 3, 6, 12, 24, and 48 h. The results indicated that at the concentration of 2%, clove powder showed highest effect on S. aureus followed by E.coli and S. typhimurium, and at 24 h under refrigeration, clove powder led to a significant reduction of bacteria counting.
2.3. The Application of Clove as Antimicrobial Agents in Food Packaging
Clove EO and its functional extracts have been incorporated into films, the antimicrobial activities of which have been evaluated in some studies. In a study, chitosan at high, moderate and low molecular mass were elaborated with antimicrobial films which were incorporated with EOs and extracts from two spices . Then the antimicrobial effects of the films were investigated on E. coli, S. typhimurium, S. aureus, B. cereus, and L. monocytogenes. The films prepared by low molecular mass chitosan with 2% EO and ethyl heptanoate extract from clove showed antimicrobial activities against a majority of the tested strains. In another study, the researchers tested the antimicrobial activities of EOs and functional extracts of cumin, clove, and elecampane against E. coli, S. typhimurium, B. cereus, S. aureus, and L. monocytogenes by determining the MICs and MBCs . They also evaluated the antibacterial activities of edible films prepared by EOs and functional extracts of spices based on chitosan polymeric structure against the same bacteria by determining the DIZs. Clove EO showed the best inhibitory effects with the MIC of 500 mg/L on all the bacteria tested, clove extracts showed very similar MICs to those of EO, except ethyl caproate extract of clove against L. monocytogenes (MIC of 750 mg/L) and ethyl heptanoate extract of clove against B. cereus (MIC of 250 mg/L). Among the chitosan films added with EOs, only clove showed inhibition zones of all tested bacteria except L. monocytogenes. The ethyl heptanoate extract of clove film also possessed antibacterial activities against all tested bacteria, weaker than those of clove EO though. Liu et al.  evaluated the antimicrobial activities of spice EOs against microbial populations in chilled pork stored in PE film antimicrobial package using the disk diffusion method to determine the DIZs and serial dilution assay to determine the MICs. Clove EO was the most effective against microorganisms tested among all the spice EOs tested. The MICs of clove EO were 0.10%, 0.10%, and 0.30% v/v against Enterobacteriaceae, S. aureus, and Pseudomonas sp., respectively. Spice EOs possessed the ability to decrease the number of spoilage populations, but not the species diversity of spoilage microbiota.
Collectively, clove EO and extracts could prevent against some food spoilage and foodborne pathogens (Table 1), especially Gram-positive bacteria. The MICs of clove were less than 2.5% against tested microorganisms like P. fluorescens, S. typhimurium, E. coli, B. cereus, and L. innocua. Generally speaking, the qualities of the papers cited are good and the results are reliable.
Oregano (Origanum vulgare), belonging to family Lamiaceae, has been used as food seasoning and flavoring for a long time. The major components associated with antimicrobial activities in oregano EO were proved to be carvacrol and thymol .
3.1. Antimicrobial Activities of Oregano
Babacan et al.  evaluated the antimicrobial activities of oregano extract against various Salmonella serotypes by evaluating the bacterial growth with disc diffusion method. The results showed that DIZs of oregano were 15, 19, and 16 mm for Salmonella gallinarum (S. gallinarum), Salmonella enteritidis (S. enteritidis), and S. typhimurium, respectively. Santoyo et al.  observed the antimicrobial activities of EO-rich fractions of oregano which were selectively precipitated in the second separator in different conditions against six microorganism strains (S. aureus, Bacillus subtilis (B. subtilis), E. coli, P. aeruginosa, C. albicans, and Aspergillus niger (A. niger)), using the disk diffusion and broth dilution methods. The results showed that all of the supercritical fluid extraction fractions exhibited antimicrobial effects on tested microorganisms, and the most efficient fraction was obtained with 7% ethanol at 150 bar and 40 °C. De Souza et al.  evaluated the effects of heating (at the temperatures of 60, 80, 100, and 120 °C, at a duration of 1 h for each) on the antimicrobial activities of oregano EO against 9 microorganism strains (C. albicans, Candida krusei (C. krusei), Candida tropicalis (C. tropicalis), B. cereus, E. coli, S. aureus, Yersinia enterocolitica (Y. enterocolitica), S. enterica, and Serratia marcescens (S. marcescens)), using the solid medium diffusion procedure. The results indicated that heating treatment showed no significant effects on the antimicrobial activities of EO, with the DIZs and MICs of heated EO close to those of EO kept at room temperature (MICs ranging from 10 to 40 μL/mL).
Oregano could bind to sterols in the fungal membranes of C. albicans strains , but the exact mechanisms of action on other microorganisms are to be further studied. Carvacrol, one of the major components of oregano, could interact with cell membranes through changing the permeability for small cations . As the chemical compounds in EO and extracts of oregano are complex, they could inhibit microorganisms through different cell targets.
3.2. Comparison of Antimicrobial Activities of Oregano and Other Spices
Ozcan et al.  investigated the antifungal activities of four spice decoctions against six molds (Fusarium oxysporum f. sp. phaseoli, Macrophomina phaseoli (M. phaseoli), Botrytis cinerea (B. cinerea), Rhizoctonia solani (R. solani), Alternaria solani (A. solani), and Alternaria parasiticus (A. parasiticus)). The results showed that the mycelial growth were 100% inhibited by 10% oregano decoction in culture medium. Ai-Turki et al.  tested the antimicrobial activities of aqueous extracts of four plants against E. coli and B. subtilis using the disc diffusion method. Oregano extract showed the best antibacterial effects on two bacteria compared with three other spice extracts, and B. subtilis showed more sensitivity than E. coli. Marques et al.  assessed the antimicrobial activities of the EOs of oregano and marjoram against S. aureus isolated from poultry meat using the disk diffusion method, and the MICs and MBCs were tested using the microdilution technique. All the S. aureus strains were susceptible to oregano EO with the MICs ranging from 6.25 to 25 μL/mL, but four of the isolates were resistant to ampicillin and one was resistant to tetracycline. Bozin et al.  investigated the antimicrobial activities of 3 spice EOs against 13 bacterial strains using the hole-plate agar diffusion method and 6 fungi by the microdilution technique. The results indicated that the most effective antibacterial activities were expressed by oregano EO, even on multiresistant strains of P. aeruginosa and E. coli. Viuda-Martos et al.  studied the antimicrobial activities of EOs from six spices against six bacteria (Lactobacillus curvatus (L. curvatus), Lactobacillus sakei (L. sakei), Staphylococcus carnosus (S. carnosus), Staphylococcus xylosus (S. xylosus), Enterobacter gergoviae (E. gergoviae) and Enterobacter amnigenus (E. amnigenus)), using the disc diffusion method. Oregano EO was the most effective against bacteria tested, with DIZs ranging from 35.29 mm (S. xylosus) to 57.90 mm (E. amnigenus). Santurio et al.  reported the antimicrobial activities of EOs of eight spices against E. coli strains isolated from poultry and cattle faeces by determining the MICs using the broth microdilution technique. The results showed that the most effective against all E. coli strains in the study was oregano EO. Khosravi et al.  investigated the antifungal activities of Artemisia sieberi and oregano EOs against Candida glabrata (C. glabrata) isolated from patients with vulvovaginal candidiasis by determining the MICs and minimal fungicidal concentrations (MFCs), using the broth macrodilution method. The results indicated that the EOs inhibited all tested C. glabrata isolates concentration-dependently, with the MICs ranging from 0.5 to 1100 μg/mL (mean: 340.2 μg/mL) for oregano. Dal Pozzo et al.  studied the antimicrobial activities of 7 spice EOs, and some majority constituents of these spices such as carvacrol, thymol, cinnamaldehyde, and cineole against 33 Staphylococcus spp. isolates from herds of dairy goats, by determining the MICs and MBCs using the broth microdilution method. Oregano and thyme possessed equally strong antimicrobial activities among EOs. Santos et al.  evaluated the antimicrobial activities of four spices against several bacteria like S. aureus and E. coli isolated from vongole and bacteria standard ATCC (American Type Culture Collection): E. coli, S. aureus, and Salmonella choleraesuis (S. choleraesuis), by determining the MICs using diffusion test. Oregano and clove EOs presented antimicrobial activities against all tested bacteria, but oregano presented larger DIZs of 26.7 mm (E. coli) and 29.3 mm (S. aureus). Hyun et al.  tested the antibacterial effects of various spice EOs including oregano on total mesophilic microorganisms in products (fresh leaf lettuce and radish sprouts) using the dipping method. One species of oregano (in the USA) EO showed the best effects on maintaining reduced levels of total mesophilic microorganisms in fresh leaf lettuce and radish sprouts compared with the control.
3.3. The Application of Oregano as Antimicrobial Agents in Food Packaging
The antimicrobial effects of pure EOs of four spices and chitosan-EOs films on L. monocytogenes and E. coli were evaluated in vitro by agar diffusion test . The antimicrobial activities of EOs alone and incorporated in the films were similar following the order: oregano >> coriander > basil > anise. When used in inoculated bologna samples at 10 °C and stored for five days, pure chitosan films led to 2 log reduction of L. monocytogenes, 3.6–4 log reduction of L. monocytogenes, and 3 log reduction of E. coli were observed in films incorporated with 1% and 2% oregano EO.
All the above studies are of good quality, and oregano showed strong antimicrobial activities against microorganism strains such as Staphylococcus spp. and S. aureus isolates with larger DIZs and lower MICs, MBCs, and MFCs compared with several other spices (Table 2). Future studies could focus on the application of oregano and its EO in food industry, and also the possible mode of action.
Cinnamon – Cinnamomum
Human lung tissue, directly exposed to the environmental oxidants and toxicants, is apt to be harmed to bring about acute or chronic oxidative insults. The nuclear factor erythroid 2-related factor 2 (Nrf2) represents a central cellular defense mechanism, and is a target for developing agents against oxidative insult-induced human lung diseases. Our previous study found that the EtOH extract of Cinnamomum chartophyllum protected human bronchial epithelial cells against oxidative insults via Nrf2 activation. In this study, a systemic phytochemical investigation of the aerial parts of C. chartophyllum led to the isolation of thirty chemical constituents, which were further evaluated for their Nrf2 inducing potential using NAD(P)H: quinone reductase (QR) assay. Among these purified constituents, a sesquiterpenoid bearing α, β-unsaturated ketone group, 3S-(+)-9-oxonerolidol (NLD), and a diphenyl sharing phenolic groups, 3, 3′, 4, 4′-tetrahydroxydiphenyl (THD) significantly activated Nrf2 and its downstream genes, NAD(P)H quinone oxidoreductase 1 (NQO-1), and γ-glutamyl cysteine synthetase (γ-GCS), and enhanced the nuclear translocation and stabilization of Nrf2 in human lung epithelial cells. Importantly, NLD and THD had no toxicities under the Nrf2 inducing doses. THD also demonstrated a potential of interrupting Nrf2-Keap1 protein–protein interaction (PPI). Furthermore, NLD and THD protected human lung epithelial cells against sodium arsenite [As(III)]-induced cytotoxicity. Taken together, we conclude that NLD and THD are two novel Nrf2 activators with potential application of preventing acute and chronic oxidative insults in human lung tissue.Human lung tissue, directly exposed to the environmental oxidants and toxicants, is apt to be harmed to bring about acute or chronic oxidative insults. The nuclear factor erythroid 2-related factor 2 (Nrf2) represents a central cellular defense mechanism, and is a target for developing agents against oxidative insult-induced human lung diseases. Our previous study found that the EtOH extract of Cinnamomum chartophyllum protected human bronchial epithelial cells against oxidative insults via Nrf2 activation. In this study, a systemic phytochemical investigation of the aerial parts of C. chartophyllum led to the isolation of thirty chemical constituents, which were further evaluated for their Nrf2 inducing potential using NAD(P)H: quinone reductase (QR) assay. Among these purified constituents, a sesquiterpenoid bearing α, β-unsaturated ketone group, 3S-(+)-9-oxonerolidol (NLD), and a diphenyl sharing phenolic groups, 3, 3′, 4, 4′-tetrahydroxydiphenyl (THD) significantly activated Nrf2 and its downstream genes, NAD(P)H quinone oxidoreductase 1 (NQO-1), and γ-glutamyl cysteine synthetase (γ-GCS), and enhanced the nuclear translocation and stabilization of Nrf2 in human lung epithelial cells. Importantly, NLD and THD had no toxicities under the Nrf2 inducing doses. THD also demonstrated a potential of interrupting Nrf2-Keap1 protein–protein interaction (PPI). Furthermore, NLD and THD protected human lung epithelial cells against sodium arsenite [As(III)]-induced cytotoxicity. Taken together, we conclude that NLD and THD are two novel Nrf2 activators with potential application of preventing acute and chronic oxidative insults in human lung tissue.
Cumulative evidences have proved that Nrf2 is highly expressed in relative abundance in human lung tissue, to counteract the insults caused by environmental oxidants and toxicants . Plenty of Nrf2 inducers, exemplified by SF, resveratrol, xanthohumol, tanshinone I, bis[2-hydroxybenzylidene]acetone, have demonstrated protective and therapeutic effects on lung disorders , , , , . Nrf2 is a good target for discovering agents possessing therapeutic effect on human lung diseases , , . In this study, experiments in vitro were performed using Beas-2B cells to evaluate the Nrf2 inducing effect of NLD and THD on human normal lung tissue. We have found that NLD and THD significantly activated Nrf2 and its downstream genes, NQO1, and γ-GCS, and enhanced the nuclear translocation and stabilization of Nrf2 in human lung epithelial Beas-2B cells (Fig. 3). According to these data, NLD and THD are verified to be canonical Nrf2 activators. More importantly, NLD and THD had no toxicity under the Nrf2 inducing doses in Beas-2B cells, and hada broad effective dose range (Fig. 3A and S2). Furthermore, NLD and THD-mediated Nrf2 activations in Beas-2B cells are intermittent (Fig. 3B), which are similar to that of chemopreventive agents (e.g. SF), but different from that of toxicants and carcinogens . https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5608562/
Anti viral herbs research article