Serapias vomeracea is an economically valuable plant belonging to the Orchidaceae family; particularly, its tubers are consumed as hot drinks. Past studies on S. vomeracea have focused on volatile components only in the aerial parts of this orchid. This study is the first to investigate the volatile compounds present in S. vomeracea tubers, which have a high commercial value. Additionally, we determined the effect of harvest time and drying method on the volatile compound profile. The tubers were harvested on two different days (May 17, 2022, and June 6, 2022) and subjected to four different drying conditions (shade drying, oven drying, shade drying after boiling, and lyophilizer drying). To determine the volatile compound profile, sample extracts were prepared by solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry. Overall, 22 volatile compounds were identified: 3 esters, 3 aldehydes, 3 alcohols, 3 terpenes, 3 alkanes, 3 carboxylic acids, 1 phenol, 1 ketone, 1 lactone, and 1 furan. The results revealed that p-cresol was the main compound. During harvesting and subsequent drying, some compounds were lost, and some new compounds were formed. Moreover, harvest time had quite limited effects on volatile compounds in the lyophilizer method. Cluster analysis revealed that the combination of harvest time and drying was effective in the distribution of volatile compounds in salep powder.

En tr This study was carried out to determine tea (Camellia sinensis L. O. Kuntze) genotypes with high antioxidant activity and also high total phenolic content (TPC) in Rize/Turkey conditions in 2017. In the research, the seeds collected from tea plantations located at different five locations of Rize were used. Plants were grown under controlled conditions in pots in greenhouse at first and then transferred to field conditions. Harvest of fresh leaves was realized for 3.5 leaves (three leaves and bud) in August. Ferric-Reducing Antioxidant Power (FRAP) and total phenol content of young leaves of selected 103 genotypes were determined. As a result, FRAP values varied between 638.4 and 1093.0 mg FeSO4 g-1 dw while total phenol content varied from 210.9 to 450.6 mg GAE g-1 dw depending on the genotypes. FRAP values belonging each genotype group representing locations were very close to each other. On the other hand, 87 of a total of 103 genotypes had high antioxidant values. The fact that the genotypes showed a high level of antioxidant activity and total phenol content reveals the presence of evaluable tea genotypes to be used in tea breeding in Rize. Bu çalışma toplam fenolik içeriği (TPC) ve antioksidan aktivitesi yüksek çay (Camellia sinensis (L.) O. Kuntze) genotiplerinin belirlenmesi amacıyla Rize/Türkiye koşullarında 2017 yılında yürütülmüştür. Araştırmada, Rize’nin farklı lokasyonlarında yer alan çay plantasyonlarından toplanmış tohumlar kullanılmıştır. Saksılarda kontrollü koşullarda yetiştirilen bitkiler daha sonra açık hava koşullarına taşınmıştır. Genç yaprakların hasadı, Ağustos ayı içinde 3.5 yaprak üzerinden yapılmıştır. Liyofilizatörde kurutulan toplam 103 genotipe ait taze yaprakların antioksidan değerleri ve toplam fenol içerikleri tespit edilmiştir. Sonuç olarak, incelenen genotipler içinde elde edilen ortalama FRAP değerleri 638.4-1093.0 mg FeSO4/g dw; toplam fenol içeriği ise 210.9-450.6 mg GAE g-1 dw arasında değişim göstermiştir. Lokasyonları temsil eden her bir genotip grubuna ait ortalama FRAP değerleri birbirine çok yakın çıkmıştır. Diğer taraftan, toplam 103 genotip içinden 87 tanesi yüksek antioksidan değerlere sahip olmuştur. Genotiplerin yüksek düzeyde antioksidan aktivite ve toplam fenol içeriği göstermesi, Rize'de çay yetiştiriciliğinde kullanılabilecek değerli çay genotiplerinin varlığını ortaya koymaktadır.

Ülkemiz Çay tarım alanlarında bilinçsizce yapılan gübrelemeler toprak yapısının bozulmasına ve ürün kalitesinin azalmasına neden olmaktadır. Bu çalışma, toprak ve yaprak analizleri yapılarak, elde edilen sonuçlar doğrultusunda çay üreticilerine örnek olabilecek bir gübreleme programının oluşturulması amacıyla yapılmıştır. Çay üreticilerinin yaygın olarak kullandığı 100 kg da-1 25-5-10 kompoze gübre yanında, 70 kg da-1 25-5-10 kompoze gübre, 70 kg da-1 25-5-10 kompoze gübre + (Fe, Zn, Cu, Mn), 70 kg da-1 25-5-10 kompoze gübre + (Kalsiyum karbonat), 70 kg da-1 25-5-10 kompoze gübre + (Magnezyum karbonat + Kalsiyum karbonat) ve 70kg da-1 25-5-10 kompoze gübre + (Fe, Zn, Cu, Mn, Kalsiyum karbonat) uygulamaları yapılmıştır. Kompoze gübreye ek olarak verilen mikro elementler yapılan toprak analizleri dikkate alınarak hesaplanmıştır. Doğal kil minerali olan kaolinin % 3 ve % 6’lık dozlarının da denendiği çalışmada, yapılan tüm uygulamaların yaş ve kuru çay verimi üzerine etkileri incelenmiştir. Çalışma sonucunda, üreticinin çayda kullanmış olduğu gübre miktarı %30 oranında azaltıldığı halde yaprak ve toprak analizleri doğrultusunda uygulanan mikro besin elementlerinin ilavesi ve kaolin uygulamaları ile verim ve kalite kayıplarının yaşanmadığı görülmüştür. Yapılan gübre uygulamaları içerisinde özellikle 70 kg da-1 25-5-10 kompoze gübre + (Kalsiyum Karbonat), ile 70 kg da-1 25-5-10 kompoze gübre + (Fe, Zn, Cu, Mn) ön plana çıkmıştır.

This study was carried out in Rize province in 2016, on fresh leaf samples collected from an organic tea plantation. In this study, the aim was to determine the effect of pruning age (1st year, 3rd year and 5th year following the last pruning) and diurnal variability on antioxidant activity and dry matter rate in tea leaves depending on shoot periods. When the pruning age was considered, the highest antioxidant activity was obtained from the plants which were in 5th pruning age in the 1st shoot period with 4991,1 μmol FeSO4/g dw. In terms of the same trait, the effect of pruning age on antioxidant activity during the 2nd shoot period was insignificant, while the highest antioxidant activity in the third shoot period was obtained from 1st pruning age with 7229.2 μmol FeSO4/g dw. As a general average, considering intraday collecting time, antioxidant activity in leaves collected in morning (07.00) and at noon (12.00) was very close to each other, while the collected leaves in the evening (17.00) had higher values. The dry matter rates obtained from the 1st, 3rd and 5th pruning ages were 23.45%, 25.23% and 25.45% respectively. When the shoot period was considered, the lowest dry matter rate was 20.17% in the first shoot period and the highest dry matter rate was 28.8% in the 2nd shoot period and high values were obtained from the leaves collected at noon.

The objective of this work was to compare salep orchid species based on the composition of the volatile compounds of their tubers. Tuber samples extracted by solid-phase microextraction were analyzed by gas chromatography-mass spectrometry. In all studied species, p-cresol was the main volatile compound detected. The highest p-cresol proportion was found in Anacamptis laxiflora (76.31%), followed by Ophrys sphegodes subsp. mammosa (62.72%), Orchis coriophora (55.95%), and Anacamptis pyramidalis (21.19%). The proportions of the other volatile compounds also varied significantly between the evaluated species. The clustering analysis of the species according to their volatile compounds showed that A. laxiflora and O. coriophora were the closest, while A. laxiflora and A. pyramidalis were the most distant.