Üzerlik tohumu, ardıç tohumu ve yaban mersini bitkisel çaylarının antioksidan ve toplam fenolik madde özelliklerinin incelenmesi
Investigation of antioxidant and total phenolic material properties of herbal tea of peganum harmala seeds, juniper seeds and blueberry fruits
Yazar: NUR AYBÜKE SOYYİĞİT
Danışman: PROF. DR. MUSTAFA GÜLFEN
Sakarya Üniversitesi / Fen Bilimleri Enstitüsü / Kimya Ana Bilim Dalı / Analitik Kimya Bilim Dalı
Derece: Yüksek Lisans, 2023
Konu: Kimya = Chemistry
Dizin: Antioksidanlar = Antioxidants ; Ardıç = Juniper ; Bitkisel çaylar = Herbal teas ; Fenolik maddeler = Phenolic matters ; Metal iyonları = Metal ions ; Tohumlar = Seeds ; Yaban mersinleri = Blueberries ; Üzerlik = Harmala

Özet:
Bu çalışmada üzerlik tohumu (Peganum Harmala L), ardıç tohumu (Juniperus Communis L.) ve yaban mersini (Vaccinium Myrtillus L.)' nin bitki çaylarında suda çözünür toplam antioksidan kapasiteleri, toplam polifenolik maddeler ve metal iyonlarının analizleri yapılmıştır. Bitkisel numunelerin su ile ekstraksiyon işlemleri, 20, 40, 60 ve 80 dakikalık farklı ekstraksiyon sürelerinde ve 70, 80, 95 ve 100 °C farklı sıcaklıklar da 200 mL saf suda yaklaşık 1 g bitkisel numune kullanılarak çalışılmıştır. Sulu çözeltilerindeki çözünmüş toplam antioksidan kapasiteleri ferri-ferrisiyanür indirgeme yöntemi kullanılarak belirlenmiştir ve UV-gör. bölge absorpsiyon spektrofotometresi kullanılarak 690 nm dalga boyunda ölçülmüştür. Sulu çözeltisindeki çözünmüş toplam polifenolik madde miktarları, Folin-Ciocalteu reaktif yöntemi ile UV-gör. bölge absorpsiyon spektrofotometresi ile 760 nm dalga boyunda ölçülerek belirlenmiştir. Bitkisel örneklerin su ve etanol ekstraktlarının UV-gör. bölge absorpsiyonu ve floresans spektrumları doğrudan ölçülmüştür. Üzerlik tohumu çözeltileri, sulu ekstraktında 200-445 nm, etanoldeki ekstraktında 200-440 nm dalga boyları aralığında UV-gör. bölge absorpsiyon spektrumu gösterirken, ardıç tohumu bitkisi sulu ekstraktında 200-420 nm, etanoldeki ekstraktında 200–380 nm dalga boyları aralığında, yaban mersini bitkisi sulu ekstraktında 200-500 nm, etanoldeki ekstraktında 200–380 nm dalga boyları aralığında absorpsiyon spektrumu göstermiştir. UV-gör. fluoresans (FL) spektrokopisi ölçümlerinde, farklı uyarılma dalga boylarında farklı FL emisyonları gözlenmiştir. UV ışık altında, üzerlik turkuaz renkli FL emisyonu verirken, ardıç ve yaban mersini mavi renkli FL emisyonu verdiği gözlenmiştir. Ayrıca suda çözünür metal iyonları indüktif eşleşmiş plazma- optik emisyon spektrometresi (ICP-OES) kullanılarak analiz edilmiştir. Bitkisel numunelerin su ile ekstraksiyon işlemleri, 0,5'er gram tartılarak 100 mL saf suda 95 °C ve 100 °C'lerde, 40 dk'da çalışılmıştır. Üzerlik tohumu, ardıç tohumu ve yaban mersini su ile ekstrakte edilmiş çözeltilerinde Ca(II), Mg(II), K(I) Na(I) metal iyonları saptanırken, Fe(III), Mn(II), Cu(II) Ni(II), Cd(II), Cr(III) tespit edilmemiştir.

Anahtar Kelimeler: Üzerlik tohumu (Peganum Harmala L.), Ardıç tohumu (Juniperus Communis L.), Yaban mersini meyvesi (Vaccinium Myrtillus L.), fluoresans, toplam antioksidan kapasitesi, toplam fenolik madde, metal iyonları

Abstract:
In this study, water-soluble total antioxidant capacities, total polyphenolic substances and metal ions amounts, UV-vis. absorption and fluorescence properties of aqueous and ethanolic extracts of peganum (Peganum Harmala L.), juniper seed (Juniperus Communis L.) and blueberry (Vaccinium Myrtillus L.) herbal teas were analyzed. Peganum seeds, juniper seeds and blueberry fruits are used generally as tea, among the most preferred consumption forms, with the acceptance of natural compounds of plants as beneficial to health. The bioactive compounds and minerals are beneficial for the human body.
The extraction processes of the herbal samples with water were studied at different extraction times of 20, 40, 60 and 80 minutes and at different temperatures of 70, 80, 95 and 100 °C using approximately 1 g of herbal sample in 200 mL distilled water. The dissolved total antioxidant capacities in their aqueous solutions were determined using the ferri-ferricyanide reduction method with a UV-vis. absorption spectrophootometer. The measurements were taken at a wavelength of 690 nm on the spectrophotometer. For the peganum seeds, the total antioxidant capacities were found as 1820 mg/100 g in the extract at 70 °C for 20 minutes, while the highest value was found as 2281 mg/100 g in the extract at 100 °C for 80 minutes. In the juniper seed aqueous extract at 70 °C, the lowest value was found at the 20th minute as 343 mg/100 g, while the highest value was found in the extract at 1845 mg/100 g at 100 °C at the 80th minute. The lowest antioxidant capacity value in the blueberry juice was found at 70 °C as 170 mg/100 g in the 20th minute extract, while the highest value was found in the extract at 100 °C as 1266 mg/100 g in the 20th minute.
The amounts of dissolved total polyphenolic substances in the aqueous solution were determined by UV-vis. absorption spectrophotometer  with the Folin-Ciocalteu reagent method at a wavelength of 760 nm. The amount of the total polyphenolic substances as gallic acid equivalent, while the lowest value was found as 1884 mg/100 g at 70 °C at the 20th minute in the aqueous extract of peganum, the highest value was found at the 80th minute as 4312 mg/100 g. The lowest value was found as 343 mg/100 g in the juniper seed aqueous extract at 70 °C in the 20th minute, while the highest value was observed as 1845 mg/100 g at 100 °C in the 80th minute. The lowest total polyphenolic substance value in the blueberry fruit juice extract was 312 mg/100 g at 70 °C in the 20th minute and the highest value was found as 1065 mg/100 g at 95 °C in the 20th minute. When evaluated in general, it is predicted that the amount of the total polyphenolic substances can be transferred more to the water solution phase by increasing in temperature and time for the extracts of peganum and juniper seeds. 
On the other hand, the decrease in the dissolved total polyphenolic substances was observed in blueberry fruit with the prolongation of the brewing time at high temperature is caused by the deterioration in the structures of heat-sensitive phenolic substances in its structure. When the amounts of the total polyphenolic substances that passes into the water at different times and temperatures were examined, the highest value was found in the pear seed extract as 4312 mg/100 g at 100 °C in the 80th minute, the lowest value was found in the blueberry fruit as 312 mg/100 g at 70 °C. in the 20th minute.
The UV-vis. absorption and fluorescence emission spectra of the water and ethanol extracts of peganum seed, juniper seed and blueberry fruit samples were measured directly. The aqueous extracts were prepared at 95 °C for 40 min and the ethanolic extracts were at 50 °C for 40 min. The peganum extract  showed the absorption bands between 200-445 nm in water and 200-440 in EtOH, the juniper extracts were between 200-420 nm in water and 200–380 nm 200-380 nm in EtOH,  and blueberry extracts were 200-500 nm in water and 200–380 nm in EtOH.
It was found that the FL emission was obsereved at 478 nm wavelength when it was excited at 368 nm for the aqueous extract of peganum plant, and when excited at 383 nm in the EtOH extract. The FL emission was observed at 343 nm wavelength when excited at 260 nm for Juniper seed aqueous extract and n ethanolic extract. The blueberry water extract has a FL emission spectrum at 346 nm wavelength when excited at 260 nm, and the ethanol extract gives FL emission spectrum at 338 and 404 nm when excited at 260 nm. The blueberry extract emits FL emission in turquoise color, while juniper and blueberry emit FL in blue.
In addition, water-soluble metal ions were also analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES). The extraction processes of the herbal samples, weighing 0.5 grams, were performed in 100 mL distilled water at 95 °C and 100 °C for 40 minutes. Ca(II), Mg(II), K(I) Na(I) metal ions were detected in water-extracted solutions of the peganum seeds, the juniper seeds and blueberry fruits. Fe(III), Mn(II), Cu(II) Ni (II), Cd(II), Cr(III) were not detected. 
In the peganum harmala  water extract, Ca(II), Mg(II), Na(I) and K(I) ions were found as  2.11 - 2.18 mg /100 g, 31.74 - 31.79 mg / 100 g, 7.14 – 7.63 mg / 100 g and 140.71 – 158.72 mg / 100 g, respectively. In the juniper water extract, Ca(II), Mg(II), Na(I) and K(I) ions were found as  3.16  - 5.35 mg /100 g, 7.50 – 10.12 mg / 100 g, 2.11 – 2.15 mg / 100 g and 34.25 – 38.9 mg / 100 g, respectively. In the blueberry  water extract, Ca(II), Mg(II), Na(I) and K(I) ions were found as  15.11  - 16.27 mg /100 g, 0.31  – 0.79 mg / 100 g, 2.43 – 2.50 mg / 100 g and 7.53 – 7.73 mg / 100 g, respectively.  It was observed that peganum harmala and the juiper water extracts have high Mg(II) and K(I) contents and  he blueberry has high Ca(II) and K(I) contents. 
In this study, it was observed that the amount of antioxidant values increased with the increase in temperature and time, while the deterioration of antioxidant structures occurred at very high temperatures and long periods. In recent years, with the increasing awareness of the importance of the antioxidants in nutrition, research and orientation towards foods with high antioxidant content has increased. It has been determined that the aroma, taste and odor of the prepared plant extracts were reached in a 40-minute steeping at 95 °C. While little or no aroma transition can occur in shorter brewing periods and low temperatures, it has been observed that taste and aroma are lost in long-term boiling processes.

Keywords: Peganum harmala (Peganum Harmala L.)., Juniper seed (Juniperus Communis L.,), Blueberry berry (Vaccinium Myrtillus L.), fluorescence, total antioxidant capacity, total phenolic substance, metal ions