Sürdürülebilir Kalkınma Amaçları

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Yazarlar

• Ayata, Umit(2)
• Domingos, Idalina(2)
• Esteves, Bruno(2)
• Ferreira, José(2)
• Akmeşe, Osman(1)
• Aygül, İmdat(1)
• Baltacı, Cemalettin(1)
• Can, Zehra(1)
• Cruz-Lopes, Luisa(1)
• Demir Kanbur, Esra(1)
• Dulyanska, Yuliya(1)
• Ecem-Bayram, Nesrin(1)
• Ferreira, Miguel(1)
• Fidan, Muhammed Said(1)
• Gercek, Ynsuf Can(1)
• Kara, Yakup(1)
• Kolayli, Sevgi(1)
• Okumus Yukunc, Gulsah(1)
• Ozkok, Aslı(1)
• Sahin, Sirri(1)
• Sefalı, Abdurrahman(1)
• Sen, Ali(1)
• Tanugur Samanci, Aslı Elif(1)
• Öz, Mehmet(1)

• MakaleYalnız künye2026Scopus SJRQ4/r/bayburt/11207
  CORRELATION BETWEEN THE CHEMICAL COMPOSITION OF WOOD AND THE INCREASING OF ITS CALORIFIC VALUE THROUGH HEAT TREATMENT; [CORRELAÇÃO ENTRE A COMPOSIÇÃO QUÍMICA DA MADEIRA E O AUMENTO DO PODER CALORÍFICO ATRAVÉS DO TRATAMENTO TÉRMICO]; [CORRELACIÓN ENTRE LA COMPOSICIÓN QUÍMICA DE LA MADERA Y EL AUMENTO DE SU PODER CALORÍFICO MEDIANTE TRATAMIENTO TÉRMICO]

  Domingos, Idalina; Ferreira, Miguel; Ferreira, José; Dulyanska, Yuliya; Ayata, Umit; Esteves, Bruno

  Introduction: The greatest importance of biomass lies in its Higher Heating Value (HHV), when considered for energy production. The calorific value is significantly affected by the changes in the chemical composition of the wood that occur during heat treatment. Objective: To understand the effect of heat treatment on the calorific value of the chemical constituents of two hardwoods: Sapelli and chestnut, and two softwoods: Scots pine and Siberian pine. Methods: The calorific value was determined by a Parr calorimeter – model 6400. The content of extractives was determined by successive Soxhlet extraction using about 3 g of each sample and 150 ml of dichloromethane, ethanol, and water as solvents. The extractives content was determined in accordance with TAPPI 204, and insoluble lignin by the Klason method Tappi T 222 om-02. For the determination of holocellulose, the acid chlorite method was used. Results: The calorific value of untreated wood ranged from 18.98 MJ/kg for chestnut to 20.35 MJ/kg for Siberian pine. Heat treatment resulted in an increase in the calorific value for most of the wood samples studied. Conclusion: The rise in HHV observed during heat treatment in softwoods and hardwoods is mainly due to the increase in lignin content, although dichloromethane extractives also play an important role.

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• MakaleAçık Erişim2025Scopus SJRQ3/r/bayburt/11799
  Chemical composition of essential oils and comparative analysis of enzyme inhibitory, antioxidant and antimicrobial activities in essential oils of endemic Gelasia sericea (Aucher ex DC.) Zaika, Sukhor. & N. Kilian

  Fidan, Muhammed Said; Baltacı, Cemalettin; Akmeşe, Osman; Sefalı, Abdurrahman; Aygül, İmdat; Öz, Mehmet

  In this study, essential oil from the aerial parts of Gelasia sericea (Aucher ex DC.) Zaika, Sukhor. & N. Kilian was extracted via hydrodistillation using a Clevenger apparatus. GC-MS/FID analysis determined aldehydes (28.31%) as the dominant group, with eucalyptol (8.71%) as the main constituent. Antioxidant activities were exhibited using DPPH, ABTS, and FRAP assays, with the essential oil demonstrating relatively higher antioxidant properties. The essential oil also showed higher levels of bioactive components, including total antioxidant capacity (160.26 mg AA eq./100 mL), total phenolic content (21.57 mg GA eq./100 mL), and total flavonoid content (14.85 mg QE eq./100 mL). While G. sericea essential oil demonstrated some antioxidant activity, it was significantly lower compared to the reference standard ascorbic acid (AA). The antimicrobial results showed relatively higher antimicrobial activity compared to most bacterial and fungal strains, as evidenced by lower MIC and MBC values and larger inhibition zones. Nevertheless, chloramphenicol (CH) and nalidixic acid (NA) continually showed superior antimicrobial efficacy, with the lowest MIC and MBC values and the largest inhibition zones. The essential oil also demonstrated potent enzyme inhibitory activity, especially against CA-II, AChE, and BChE, with the lowest IC50 value observed for CA-II, highlighting its potential as a potent enzyme inhibitor. However, the essential oil exhibited comparatively greater inhibition against AChE, BChE and α-amylase but was less effective overall. These findings suggest that the G. sericea essential oil has important antioxidant potential and enzyme inhibitory activity, while the essential oil shows varying efficacy across different enzymes.

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  AtıfOpenAlex1

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• MakaleYalnız künye2025Scopus SJRQ2/r/bayburt/11001
  Bee bread from Anatolia: its chemical composition, phenolic and aromatic profiles, and antioxidant properties

  Kolayli, Sevgi; Okumus Yukunc, Gulsah; Kara, Yakup; Demir Kanbur, Esra; Can, Zehra; Ozkok, Aslı; Tanugur Samanci, Aslı Elif

  This study investigated the botanical origin, chemical composition, phenolic and volatile aromatic profiles, and antioxidant activities of 11 bee bread samples from different regions of Anatolia, Turkey. The bee bread samples contained high amounts of proteins (19.61 g/100 g) and lipids (6.43 g/100 g). The bee breads were determined to have a rich mineral content. The antioxidant potential of the bee breads was predicted using total phenolic content (TPC), total flavonoid content (TFC), total condensed tannin (TCT) content, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) assays. The TPC of the bee breads ranged between 2.041 ± 0.170 and 3.224 ± 0.006 mg GAE/g, while the TFC ranged from 0.323 ± 0.004 to 1.903 ± 0.017 mg QE/g. The FRAP assay showed antioxidant activity ranging from 17.778 ± 0.207 to 49.752 ± 0.856 µmol FeSO4.7H2O/g, and the DPPH values were between 1.054 ± 0.009 and 4.366 ± 0.014 SC50 mg/mL. Using 25 standards, RP-HPLC-PDA quantified the composition of the phenolic compounds, attributed to their antioxidant activity. The highest concentrations were detected for t-cinnamic acid, rutin, and p-coumaric acid. One hundred nineteen volatile aromatic compounds were determined in the bee breads by solid-phase microextraction coupled with gas chromatography and mass spectrometry (SPME-GC-MS). The obtained values suggest that bee breads could serve as a potential source of nutrients and bioactive compounds for value-added food supplements and functional foods.

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  AtıfScopus12·WoS13·OpenAlex15

  İncele
• MakaleAçık Erişim2020Scopus SJRQ2/r/bayburt/13188
  Calorific power improvement of wood by heat treatment and its relation to chemical composition

  Domingos, Idalina; Ayata, Umit; Ferreira, José; Cruz-Lopes, Luisa; Sen, Ali; Sahin, Sirri; Esteves, Bruno

  Chemical composition influences the calorific power of wood, mainly due to the calorific power of structural compounds and extractives. Heat treatment changes the chemical composition of treated wood. This work studies the relationship between chemical composition and calorific power improvement by heat treatment. Samples were heat-treated by the ThermoWood process ® for 1 h and 2 h. High heating value (HHV) and chemical composition; lignin, cellulose, hemicelluloses and extractives in dichloromethane, ethanol, and water were determined. The HHV of untreated wood ranged between 18.54-19.92 MJ/kg and increased with heat treatment for all the tested species. A positive linear correlation was found between HHV and Klason lignin (R2 = 0.60). A negative trend was observed for holocellulose, cellulose, and hemicelluloses content against HHV, but with low determination coefficients for linear regression. The best adjust for polysaccharides was found for hemicelluloses content. A positive correlation could be found for dichloromethane extractives (R2 = 0.04). The same was obtained in relation to ethanol extractives with R2 = 0.20. For water and total extractives, no clear positive or negative trends could be achieved. The results showed that the HHV of wood increased with heat treatment and that this increase was mainly due to the increase in lignin content.

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  AtıfScopus32·WoS27·OpenAlex38

  İncele
• MakaleYalnız künye2019Scopus SJRQ4/r/bayburt/12425
  Appropriate maceration duration for the extraction of propolis

  Ecem-Bayram, Nesrin; Gercek, Ynsuf Can

  The importance of the use of natural products as nutritional supplements in order to increase the quality of life and prevent diseases has increased in recent years. Among these products, propolis produced by honey bees is collected from plants and has a very complex structure in terms of chemical content. Propolis and its extracts have been used by humans for centuries because of its various bioactive properties. Although different methods can be used in the extraction stage, the most commonly used technique is extraction by maceration. However, there is no standard time period for extraction of propolis by maceration. We aimed to determine the changes in the concentrations of flavonoid group compounds pinocembrin, chrysin, tectochrysin, pi-nostrobin chalcone, gengwanin, naringenin and galangin from propolis samples exposed to seven different periods (1, 2, 5 10, 15, 20, 30 days) of maceration using GC-MS. The flavonoids pinocembrin, chrysin, tectochrysin, and naringenin reached their maximum concentrations at the end of 15 days of maceration and a decrease in their concentrations was observed after this period. The concentrations of other flavonoids did not show a steady increase or decrease with different maceration times. As a result, it can be said that the appropriate duration of maceration to extract the flavonoids responsible for propolis' numerous activities varies depending on the origin of the propolis and the nature of the compounds to be extracted.

  AtıfScopus9

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