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The effects of voltage on the methane production rate (k) of various types of anaerobic sludge biomasses are quantitatively demonstrated. Voltage is supplied to the anaerobic digestion (AD) sludges independently and quickly improves the methane production rates and specific methanogenic activities (SMAs), regardless of bio-electrochemical activation of the sludge. This supports previous findings that bio-electrochemical AD (BEAD) shows higher stabilization and methane production rates than those of AD. However, in reactors fed with H2/CO2, SMA and k are not significantly increased by the voltage supply, indicating that direct electron transfer for hydrogenotrophic methanogenesis is not a major methane formation pathway. The voltage supply contributed to indirect electron transfer for H2 production. Therefore, indirect electron transfer via H2 is a significant factor in hydrogenotrophic methanogenesis. These findings indicate changes in the general pathways of AD achieved using a voltage supply and provide a better understanding of previous BEAD studies.

Quantitative evaluation of methane production either in bulk sludge or biofilm on electrodes was performed in a bio-electrochemical anaerobic digestion (BEAD) reactor with a lower electrode surface area/reactor working volume (A/V) ratio (7.0 m2/m3). Methane production by electrochemical reaction was also evaluated in the BEAD reactor with a biofilm-free electrode under the same conditions as in other experimental sets. The contributions of bulk sludge, biofilms on the electrodes, and electrochemical reactions in the BEAD reactor, on methane production, were 70.2%, 29.8%, and 0%, respectively. The principal methane-producing reactions occurred in the bulk sludge facilitated by H2-dependent methylotrophic and hydrogenotrophic methanogens. Hydrogenotrophic methanogenesis was also the main methane-producing reaction in the biofilms attached to the bio-electrodes. Quantitative analysis of methane production (29.8%) in the biofilm revealed that bio-electrochemical processes involving H2 and direct bio-electrochemical methane production contributed 8.7% and less than 0.1%, respectively. Interestingly, biochemical processes (21.1%) contributed the most to the overall production of methane in the biofilm. Bulk sludge contributed more to methane production than the biofilm, but the methane production per unit mass of volatile solid on the electrodes was about 1.6-times higher than that of bulk sludge. Methane was not produced in the BEAD reactor with biofilm-free electrodes. Therefore, formation and maintenance of biofilms on the electrodes are essential for improved methane production in BEAD reactors.

In this study, the metabolism of methanol and changes in an archaeal community were examined in a bioelectrochemical anaerobic digestion sequencing batch reactor with a copper-coated graphite cathode (BEAD-SBRCu). Copper-coated graphite cathode produced methanol from food waste. The BEAD-SBRCu showed higher methanol removal and methane production than those of the anaerobic digestion (AD)-SBR. The methane production and pH of the BEAD-SBRCu were stable even under a high organic loading rate (OLR). The hydrogenotrophic methanogens increased from 32.2 to 60.0%, and the hydrogen-dependent methylotrophic methanogens increased from 19.5 to 37.7% in the bulk of BEAD-SBRCu at high OLR. Where methanol was directly injected as a single substrate into the BEAD-SBRCu, the main metabolism of methane production was hydrogenotrophic methanogenesis using carbon dioxide and hydrogen released by the oxidation of methanol on the anode through bioelectrochemical reactions.

Acetobacter pasteurianus AFY-4 was isolated from fermented vinegar in Hongcheon-gun, Gangwon-do. The A. pasteurianus AFY-4 strain had a higher tolerance to low-pH. Optimization of acetic acid fermentation of hardy kiwi (Actinidia arguta) was conducted using the A. pasteurianus AFY-4 strain based on the response surface methodology (RSM). The optimization of acetic acid fermentation for producing hardy kiwi vinegar was determined by five levels of initial ethanol, initial acetic acid, and acetic acid bacteria (AAB) inoculum volume, using the central composite design. The acetic acid yield and residual ethanol for acetic acid fermentation of hardy kiwi optimized by the RSM were significantly different. The optimal conditions for acetic acid fermentation of hardy kiwi vinegar were 8.95% of the initial ethanol, 1.86% of the initial acetic acid, and 25.02% of the AAB inoculum volume.

Nitidine chloride (NC) is a natural alkaloid compound derived from the plant Zanthoxylum nitidum and is known for its therapeutic anticancer potential. In this study, we investigated the effects of NC on growth and signaling pathways in human oral cancer cell lines and a tumor xenograft model. The apoptotic effects and related molecular targets of NC on human oral cancer were investigated using trypan blue exclusion assay, DAPI staining, Live/Dead assay, Western blotting, Immunohistochemistry/Immunofluorescence and a nude mouse tumor xenograft. NC decreased cell viability in both HSC3 and HSC4 cell lines; further analysis demonstrated that cell viability was reduced via apoptosis. STAT3 was hyper-phosphorylated in human oral squamous cell carcinoma (OSCC) compared with normal oral mucosa (NOM) and dephosphorylation of STAT3 by the potent STAT3 inhibitor, cryptotanshinone or NC decreased cell viability and induced apoptosis. NC also suppressed cell viability and induced apoptosis accompanied by dephosphorylating STAT3 in four other oral cancer cell lines. In a tumor xenograft model bearing HSC3 cell tumors, NC suppressed tumor growth and induced apoptosis by regulating STAT3 signaling without liver or kidney toxicity. Our findings suggest that NC is a promising chemotherapeutic candidate against human oral cancer.

Nitidine chloride (NC) was recently reported to exhibit a wide range of pharmacological properties for several diseases, including cancer. Here we report for the first time that NC is a potential therapeutic agent for mucoepidermoid carcinoma (MEC) occurring in the head and neck because it suppresses X chromosome-linked inhibitor of apoptosis protein (XIAP) in human MEC in vitro and in vivo. The antitumor effects of NC were evaluated by trypan blue exclusion assay, western blotting, live/dead assay, 4',6-diamidino-2-phenylindole (DAPI) staining, human apoptosis antibody array, immunofluorescence staining, immunohistochemistry, small interfering RNA assay, transient transfection of XIAP overexpression vector, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and histopathological examination of organs. NC inhibited cell viability and induced caspase-dependent apoptosis in vitro. A human apoptosis antibody array assay showed that XIAP is suppressed by NC treatment. XIAP was overexpressed in oral squamous cell carcinoma (OSCC) tissues that arose from the head and neck, and high XIAP expression was correlated with poor prognosis in OSCC patients. XIAP depletion significantly increased apoptosis, and ectopic XIAP overexpression attenuated the apoptosis induced by NC treatment. NC suppressed tumor growth in vivo at a dosage of 5 mg/kg/day. The number of TUNEL-positive cells increased and the protein expression of XIAP was consistently downregulated in NC-treated tumor tissues. In addition, NC caused no histopathological changes in the liver or kidney. These findings provide new insights into the mechanism of action underlying the anticancer effects of NC and demonstrate that NC is a promising therapeutic agent for the treatment of human MEC of the head and neck. KEY MESSAGES: • Nitidine chloride induces caspase-dependent apoptosis in MEC of the head and neck. • High XIAP expression correlates with poor prognosis of OSCC patients. • Nitidine chloride suppresses tumor growth in vivo without any systemic toxicities. • Targeting XIAP is a novel chemotherapeutic strategy for MEC of the head and neck.

OBJECTIVES: The purpose of this study was to investigate optimization of spray drying conditions for water-soluble powder using response surface methodology that is a statistical procedure used for optimization studies. METHODS: First, conditions of the extract used for spray drying were set. We compared heat water extraction (60–100 °C) with ethanol extraction (10–50%). After final selection of the method of extract used for spray drying, spray drying conditions were set. Independent variables included the additive contents of maltodextrin (X(1)), inlet temperature (X(2)), and air flow rate (X(3)). The dependent variables were yield, water absorption index (WAI) and total phenolic compounds. RESULTS: The yield was highest in 100 °C heat water extraction. The content of rutin was 29.77 mg/100 g in 90 °C heat water extraction, 28.07 mg/100 g in 100 °C heat water extraction and 24.24 mg/100 g in 10% ethanol extraction. The heat water extraction method at 100 °C was selected as an extract of the spray dryer. Statistical analysis revealed that independent variables significantly affected all the responses. A maximum yield was obtained at 15.55% of X(1), 167.87 °C of X(2) and 50.00 mL/min of X(3). The water absorption index of asparagus increased with increasing MD ratio (X(1)), higher inlet temperature (X(2)) and higher air flow rate (X(3)). The total polyphenol contents of asparagus were higher when the MD addition ratio (X(1)) was 16.56%, the inlet temperature (X(2)) was higher and the air flow rate (X(3)) was higher. CONCLUSIONS: In this study, extracts of asparagus using different extraction methods were compared for yield and spray-dried asparagus powders were investigated for their physicochemical characteristics. We were vary the range of the temperature, air flow rate, dextrin rate and set the best method for the functionality content of asparagus. Asparagus was spray - dried using 100 °C water extraction with high yield and high rutin content. The maximum spray drying yield was obtained at 15.55% of MD ratio, 167.87 °C of inlet temperature and 50.00 mL/min of air flow rate. There will be additional processed goods development made with what we have found. FUNDING SOURCES: This study was supported by 2018 Regional Specialized Technology Development Project, Rural Development Administration, Republic of Korea. SUPPORTING TABLES, IMAGES AND/OR GRAPHS

Approximately 20% of all salivary gland cancer patients who are treated with current treatment modalities will ultimately develop metastases. Its most common form, mucoepidermoid carcinoma (MEC) is a highly aggressive tumor with an overall 5-year survival rate of ~30%. Until now, several chemotherapeutic drugs have been tested for the treatment of salivary gland tumors, but the results have been disappointing and the drugs often cause unwanted side effects. Therefore, several recent studies have focused on the potential of alternative and/or complementary therapeutic options, including the use of silymarin. The effects of silymarin and its active component silibinin on salivary gland cancer-derived MC3 and HN22 cells and their underlying molecular mechanisms were examined using trypan blue exclusion, 4′-6-diamidino-2-phenylindole (DAPI) staining, Live/Dead, Annexin V/PI staining, mitochondrial membrane potential (ΔΨm) measurement, quantitative RT-PCR, soft agar colony formation and Western blotting analyses. We found that silymarin and silibinin dramatically increased the expression of the pro-apoptotic protein Bim in a concentration- and time-dependent manner and, concomitantly, induced apoptosis in MC3 and HN22 cells. We also found that ERK1/2 signaling inhibition successfully sensitized these cells to the apoptotic effects of silymarin and silibinin, which indicates that the ERK1/2 signaling pathway may act as an upstream regulator that modulates the silymarin/silibinin-induced Bim signaling pathway. Taken together, we conclude that ERK1/2 signaling pathway inhibition by silymarin and silibinin increases the expression of the pro-apoptotic Bcl-2 family member Bim which, subsequently, induces mitochondria-mediated apoptosis in salivary gland cancer-derived cells.

Effects of pulsed electric field (PEF) technology on physicochemical properties of raw Panax ginseng roots were investigated in this study. PEF treatment was conducted with different electric field strength (0.5, 1.5, and 2.5 kV/cm) and pulse width of 25 μs. Ginseng cell and vacuole membranes were significantly affected by PEF treatment at field strengths >1.5 kV/cm. Changes in membrane systems due to PEF treatment were verified by increased ion leaching and increased cell membrane disintegration (conductivity disintegration index Z value). Observation by electron microscopy revealed vacuole destruction and plasma membrane separation following PEF treatment. Texture profile analysis showed a significant decrease in hardness (by 44%) and chewiness (by 45%) at 2.5 kV/cm. PEF treatment had little effect on proximate composition and crude saponin content of ginseng roots. However, total phenolic content (by 11%) and antioxidant activity (by 21.4% for DPPH and 3.64% for ABTS) were significantly increased. Industrial relevance Raw ginseng is normally steamed and dried to make white ginseng and red ginseng. However, using these methods is time consuming and requires much energy. Pulsed electric field (PEF) can induce the changes in physicochemical properties of ginseng with less energy for a short period of time. By using this technology, we can obtain ginseng products with high cell permeability and high antioxidant ability by tailoring the microstructure. This potentially increases the extraction of bioactive compounds in ginseng and significantly enhances the mass transfer during subsequent processing, thereby improving the efficiency of the whole process. These results could be used as basic study for the production of high-quality ginseng products using non-thermal technologies.

Objective Caffeic acid phenethyl ester (CAPE), a natural honeybee product exhibits a spectrum of biological activities including antimicrobial, anti-inflammatory, antioxidant and antitumor actions. The purpose of this research was to investigate the anticancer potential of CAPE and its molecular mechanism in human oral cancer cell lines (YD15, HSC-4 and HN22 cells). Design To determine the apoptotic activity of CAPE and identify its molecular targets, trypan blue exclusion assay, soft agar assay, Western blot analysis, DAPI staining, and live/dead assay were performed. Results CAPE significantly suppressed transformation of neoplastic cells induced by epidermal growth factor (EGF) and 12-O-tetradecanoylphorbol 13-acetate (TPA) without inhibiting growth. CAPE treatment inhibited cell growth, increased the cleavages of caspase-3 and poly (ADP-ribose) polymerase (PARP), and augmented the number of fragmented nuclei in human oral cancer cell lines. CAPE activated Bax protein causing it to undergo a conformational change, translocate to the mitochondrial outer membrane, and oligomere. CAPE also significantly increased Puma expression and interestingly Puma and Bax were co-localized. Conclusion Overall, these results suggest that CAPE is a potent apoptosis-inducing agent in human oral cancer cell lines. Its action is accompanied by up-regulation of Bax and Puma proteins.