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Öğe Biochemical and biohythane production from anaerobically digested water plant by hydrothermal liquefaction/gasification(Elsevier Ltd, 2023) Bodur, F.-G.; Güngören-Madenoğlu, T.; Özdemir, G.; Ballice, L.; Kabay, N.Water hyacinth (Eichhornia crassipes) was anaerobically digested with waste sludge in a batch system at varying total solid (TS) contents (3.3–8.3%) and temperatures (35–55 °C). Then, the high organic content of digested biomass was utilized for hydrothermal liquefaction/gasification in the batch reactor system at different temperatures (200–600 °C) to yield biofuels and biochemicals. Hydrothermal liquefaction/gasification was performed in sub- and super-critical water (above 374 °C and 221 bar) conditions. Prevailing products are some biochemical compounds (carboxylic acids, furfurals, aldehyde/ketones, phenols etc.) at lower temperatures (200–300 °C) while biohythane (total of hydrogen and methane) gaseous fuel are produced at higher temperatures (400–600 °C). The highest carbon gasification efficiency (73 g C in product/g C in feed) was obtained at 600 °C with the sample that has a high anaerobic digestion efficiency (digested at 6.3 TS% at 35 °C). The highest carbon liquefaction efficiency (37.2 g C in product/g C in feed) was obtained at 200 °C with the sample which has a low anaerobic digestion yield (digested at 8.3 TS% at 35 °C). © 2023 Hydrogen Energy Publications LLCÖğe HYDROGEN AND METHANE PRODUCTION FROM ANAEROBICALLY DIGESTED WATER PLANT BY HYDROTHERMAL GASIFICATION(International Association for Hydrogen Energy, IAHE, 2022) Bodur, F.G.; Güngören-Madenoğlu, T.; Özdemir, G.; Kabay, N.; Ballice, L.Previously, water hyacinth (Eichornia crassipes) was anaerobically digested with anaerobic sludge in batch system at varying total solid (TS) contents of 3.3 and 4.3% and at 35°C. In this study, high organic content of the digested biomass was evaluated in hydrothermal gasification in batch reactor system at different temperatures (200-500°C) to produce biofuels and biochemicals. Hydrothermal gasification was performed in sub- and super-critical water (Tc=374°C, Pc=221 bar) conditions. Prevailing products are biochemicals (glycolic acid, formic acid, acetic acid, furfural, 5-methyl furfural, phenols etc.) at lower temperatures (200-300°C) while biofuels (especially hydrogen and methane) are produced at higher temperatures (400-500°C). Nearly 63% of the feed was converted to gas and aqueous products at 500°C. © 2022 Proceedings of WHEC 2022 - 23rd World Hydrogen Energy Conference: Bridging Continents by H2. All rights reserved.Öğe Optimization and microbial community analysis for anaerobic digestion of water hyacinth (Eichhornia crassipes) with waste sludge at different solid contents and temperatures(Elsevier B.V., 2023) Öztep, G.; Güngören-Madenoğlu, T.; Özdemir, G.; Işık, E.; Serez, H.; Kabay, N.; Yüksel, M.In this study, optimum operating conditions for anaerobic digestion of water hyacinth (Eichhornia crassipes) with waste sludge was investigated at varying total solid (TS) content of the digestion solution (3.3%, 4.3%, 5.3%, 6.3%, 7.3% and 8.3%) and digestion temperature (35, 40, 45, 50 and 55 °C) to produce methane with high yield. The highest biogas yield reached experimentally was 163.2 mL/g TVS (with high CH4 content of 81.1 vol%) at 6.3% of TS content and digestion temperature of 35 °C. Kinetic parameters were estimated by using modified Gompertz, Cone and first-order kinetic models in which modified Gompertz model gave the lowest fitting errors (?1.0 to 3.7%). The effect of temperature on methane production rate was simulated by Ratkowsky model and optimum digestion temperature was found between 41.5 and 44 °C for maximum methane production at 6.3% TS. The experimental methane yields were 61.9–132.3 mL CH4/g TVS. The metagenomic sequencing was used to characterize microbial community structure of the anaerobic digestate at varying conditions and acetoclastic/hydrogenothrophic methanogenesis was equally dominated methane-producing pathways. The most abundant bacterial populations were found to be Proteobacteria, Firmicutes, Chloroflexi and Actinobacteria. Based on alpha diversity indices, it can be concluded that effect of digestion temperature on microbial richness and diversity was higher than the effect of TS content. © 2023 The AuthorsÖğe Real-Time PCR Detection of Candida Species in Biopsy Samples from Non-Smokers with Oral Dysplasia and Oral Squamous Cell Cancer: A Retrospective Archive Study(Multidisciplinary Digital Publishing Institute (MDPI), 2023) İlhan, B.; Vural, C.; Gürhan, C.; Vural, C.; Veral, A.; Wilder-Smith, P.; Özdemir, G.The impact of Candida sp. in the development of oral cancer remains uncertain and requires sensitive analytical approaches for clarification. Given the invasive capabilities of these microorganisms in penetrating and invading host tissues through hyphal invasion, this study sought to detect the presence of five Candida sp. in oral biopsy tissue samples from non-smoker patients. Samples were obtained from patients at varying stages of oral carcinogenesis, including dysplasia, carcinoma in situ, OSCC, and histologically benign lesions, and analyzed using Real-Time PCR. Oral tissue samples from 80 patients (46 males and 34 females) were included. Significantly higher C. albicans presence was detected in the mild/moderate dysplasia group compared to the healthy (p = 0.001), carcinoma in situ (p = 0.031) and OSCC groups (p = 0.000). Similarly, C. tropicalis carriage was higher in tissues with mild/moderate dysplasia compared to healthy (p = 0.004) and carcinoma in situ (p = 0.019). Our results showed a significant increase in the presence of C. albicans and C. tropicalis within the mild/moderate dysplasia group compared to other cohorts. Coexistence of these two microorganisms was observed, suggesting a potential transition from a commensal state to an opportunistic pathogen, which could be particularly linked to the onset of oral neoplasia. © 2023 by the authors.Öğe Salivary inflammatory burden in pre- and postmenopausal women: Associations with body mass index, patient-reported health, serum cytokines, and periodontal parameters(John Wiley and Sons Inc, 2023) Yakar, N.; Bostanci, N.; Özdemir, G.; Atmaca, H.; Türedi, A.; Şahin, Ç.; Köse, T.Background: The decline of estrogen levels during menopause impacts weight, mood, and overall health, both orally and systemically. This study assessed salivary levels of tumor necrosis factor alpha (TNF-?), interleukin-6 (IL-6), IL-10, and IL-7 in postmenopausal (PMW) and regularly menstruating premenopausal (RMPW) women, while considering serum cytokine levels, body mass index (BMI), periodontal health, and self-reported physical and emotional well-being. Methods: In this study, 75 PMW and 71 RMPW were included. Clinical and periodontal parameters were evaluated, and perceived health was assessed with the Women's Health Questionnaire (WHQ). Cytokine levels in both saliva and serum were quantified by enzyme-linked immunosorbent assay (ELISA). Covariate evaluations of salivary cytokines were conducted using hierarchical linear regression modeling. Results: Cytokines were detectable in saliva from 71 PMW and 67 RMPW. In the initial unadjusted model, IL-7, IL-10, and TNF-? exibited significant differences between RMPW and PMW. However, these differences became non-significant (p > 0.05) in the final model after adjusting for age, which implies a negligible effect of the investigated covariates on salivary cytokine levels when age was considered. Lower levels of IL-6 in PMW, which initially showed no significant difference, became borderline (p = 0.054) in the final model after adjusting for age. Conclusions: After adjusting for multiple factors, no significant difference was found in the salivary levels of the investigated cytokines between RMPW and PMW. Factors such as BMI, perceived health, serum cytokine levels, and periodontal parameters seem to minimally influence these levels in PMW. However, age may be a stronger confounding factor. © 2023 The Authors. Journal of Periodontology published by Wiley Periodicals LLC on behalf of American Academy of Periodontology.
