Mehmet Fuat Gülhan

This study investigated the effects of supplementing Tris semen extender with protocatechuic acid (PCA) at doses of 25, 50, and 100 µg/mL on the quality of ram spermatozoa after cryopreservation. We evaluated motility, kinematic parameters, DNA integrity, redox status, plasma membrane–acrosome integrity (PMAI), viability, and high mitochondrial membrane potential (HMMP). PCA supplementation produced concentration-dependent and parameter-specific responses. The 25 µg/mL PCA group exhibited the most favorable functional profile, demonstrating improved progressive and total motility alongside reduced DNA damage. This protective effect was evidenced by lower tail length, tail DNA percentage, and tail moment in the comet assay. Conversely, treatment with 100 µg/mL PCA appeared to exert a notable effect on the redox balance, indicated by lower malondialdehyde, total oxidant status, and oxidative stress index levels, alongside an elevated total antioxidant status (p < 0.05). However, this higher concentration (100 µg/mL) did not provide parallel DNA protection and was associated with increased comet assay indices. PMAI, viability, and HMMP were not significantly affected by PCA supplementation (p > 0.05). These findings indicate that PCA exerts dose-dependent but parameter-specific effects on frozen–thawed ram spermatozoa. Low-dose PCA, particularly 25 µg/mL, appears more suitable for preserving motility and nuclear integrity, whereas 100 µg/mL mainly improves oxidative balance.

The objective of the study was to investigate the vanillic acid's (VA) protective effects, a phenolic compound, on the ram semen after freeze–thaw. Semen was obtained from Ramlıç rams and was diluted with control (0 μg/mL VA) and VA‐supplemented Tris‐based extenders at concentrations of 1, 10 and 50 μg/mL. The diluted semen was equilibrated for 2 h at +4°C, filled into 0.25 mL straws and frozen in liquid nitrogen vapour. It was then stored in a liquid nitrogen container at −196°C. For analysis, the samples were thawed at 37°C for 30 s in a water bath. There was no difference detected among total and progressive motility as well as velocity parameters ( p > 0.05) except for rapid progressive motility ( p < 0.05). The findings support the idea that VA has an outstanding effect on reducing DNA damage ( p < 0.001). While there was no positive development with regard to total oxidant status ( p > 0.05), VA enhanced the antioxidant defences of total antioxidant status ( p < 0.05). VA administered at doses of 10 and 50 μg increased total antioxidant status ( p < 0.01). Lipid peroxidation was not directly affected by VA application ( p > 0.05); otherwise, 10 and 50 μg VA treatments showed a positive effect on viability ( p < 0.001). Based on findings, it was concluded that although VA was put in the semen extender, it did not have an ameliorative potency on sperm motility and velocity properties except for specific sub‐parameters such as rapid progressive motility. All applied doses reduced DNA damage, and 10 and 50 μg doses supported cellular viability.

Research background. Dandelion flowers have a very short shelf life. The canning process is known not only to stabilise food and preserve its nutritional content at a high level, but also to significantly extend its shelf life. For this reason, canned dandelion flowers are believed to be beneficial for both consumers and the gastronomy sector. Experimental approach. In this study, fresh dandelion (Taraxacum officinale L.) flowers were canned using sucrose syrup with different (20 and 30) degrees of Brix (°Bx) as filling medium and stored at 25 °C for 30 days. A total of 56 phytochemicals were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS), while the in vitro antioxidant activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and cupric reducing antioxidant capacity (CUPRAC) and the total phenolic content (TPC) were analysed in both the canned flowers and the syrup at different storage times (on days 10, 20 and 30). Results and conclusions. The antioxidant activities of fresh dandelion flowers were 89.6 % and 0.8 mmol Trolox equivalents (TE) per gram, respectively. The lowest DPPH (41.4 %) and CUPRAC expressed as TE (0.3 mmol/g) activities were observed on day 20 in samples stored in the 30 °Bx syrup. The TPC in fresh flowers, expressed as gallic acid equivalents (GAE) per g of extract, was 367.4 mg/g. The highest TPC in canned flowers was determined on day 10 in the samples in syrup with both °Bx. LC-MS/MS analysis identified 24 phytochemicals in fresh flowers, including quinic acid, luteolin, siranoside, chlorogenic acid, fumaric acid, caffeic acid, protocatechuic acid, quercetin, cosmosiin, isoquercitrin and apigenin. A decrease in the polyphenol content of canned flowers was observed during storage. The results indicate that canning dandelion flowers in a 30 °Bx syrup and storing them for 20 days preserved their phenolic content and antioxidant capacity. Novelty and scientific contribution. Numerous studies in the literature focus on extending the shelf life of fruit and vegetables by the canning method. However, this study fills a gap in the literature by successfully applying the canning technique to edible flowers for the first time. Furthermore, the results of this study contribute to future research on the potential commercialisation of canned dandelion flowers as a food product.

In this study, the potential of using different concentrations of agave syrup (AS) as a substrate in kombucha fermentation was investigated. After adding AS at concentrations of 3% (AS3), 5% (AS5), and 7% (AS7) to kombucha, some physicochemical, antioxidant, and microbiological analyses were conducted, alongside the determination of total phenolic content. The lowest pH value was measured as 3.13±0.13 and 2.91±0.15 in AS7 kombucha after fermentation for 7th and 14th days, respectively. The highest total soluble solids content was determined as 7.81±0.28 °Bx in AS7 kombucha on our 48th. The highest DPPH activity was observed in AS7 after 14 days (71±1.02%), metal chelating activity was highest in AS7 kombucha on day 14th (71.5%), and the total phenolic content was found to be 412±0.81 mg GAE/L and 438±0.89 mg GAE/L in AS7 on days 7th and 14th, respectively. The highest levels of acetic acid, lactic acid, and yeast counts were detected in AS7 on days 7th and 14th. The results showed that agave syrup may be an alternative sugar source to sucrose for kombucha, and polyphenols from agave may contribute to antioxidant capacity. Particularly, consumption between 7th and 14th days is recommended due to the highest functional properties observed during this period.

The aim of this study was to investigate the effectiveness of hesperidin (HES) on testicular histopathological changes, biochemical changes, and semen characteristics in rats exposed to glyphosate (GLP). The control group was given a normal diet devoid of GLP and HES, the HES group was given 100 mg/kg/day HES with the normal diet, the GLP group was given GLP at the LD₅₀/10 dose of normal feed, which was 787.85 mg/kg/day, and the GLP + HES group was given normal feed containing 787.85 mg/kg/day LD₅₀/10 dose of GLP in addition to 100 mg/kg/day HES. GLP administration reduced sperm motility, sperm plasma membrane integrity, glutathione levels, and total antioxidant levels in the testicular tissues of rats. Moreover, it caused an increase in right testis and left epididymis weights, abnormal sperm counts, malondialdehyde levels, total oxidant status, and DNA damage. The HES treatment showed curative effects on these parameters. Furthermore, HES was effective in lessening the histopathological damage that was caused by GLP. The results showedthat HES protects spermatological parameters and DNA integrity, improves antioxidant defenses, and lowers the damage and lipid peroxidation caused by GLP in testicular tissue.

In this study, sugar-free (A) and sugar-added (B) formulations of carob sherbet were fermented with water kefir grains. After 48 h of fermentation, the pH and total soluble solid content level (TSS) of A and B decreased, while the titratable acidity (TA) value increased. At the end of fermentation, Ave B formulations were stored at 4 °C for 28 days. Fermented sherbets’ 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity decreased with storage. A had 75.3% DPPH radical scavenging activity on day 0th, whereas B had 77.0%. B had less total phenolic content (TPC) than fermented A on day 0. TPC values decreased significantly, notably on days 21st and 28th of storage. After fermentation, A had more gallic acid, hesperidin, p-coumaric acid, rosmarinic acid, and syringic acid than B. A had 2.21% sucrose before fermentation and 0.95% after. On 14th days of storage, potassium and calcium had the greatest mineral levels. Compared to A, B gave higher microbial count values (Lactobacillus sp., Lactococcus sp. total mesophilic aerobic bacteria, and yeast) in the microbiological analysis results at the end of fermentation and during storage.

To the best of our knowledge, no research has been conducted to test the effects of syringic acid (SA) on ram semen freezing within the scope of natural antioxidants added to semen extenders. Therefore, this study had two main objectives. First, to test whether adding SA to ram semen freezing extender has a protective effect and contributes positively to sperm kinetic, plasma and acrosome integrity, mitochondrial membrane potential, lipid peroxidation, oxidant and antioxidant and DNA damage parameters after thawing. Second, it was to determine at what concentration the SA supplemented to the extender could be applied by in vitro studies by preserving the fertilization ability of frozen semen at the highest level. In the study, six individuals of Sönmez rams were used. The semen was collected from the rams using an artificial vagina and pooled. The pooled semen was divided into five different groups and extended with 0, 0.5, 1, 2 and 4 mM SA (control C, SA0.5, SA1, SA2 and SA4, respectively). After dilution, the semen samples were kept at 4°C for 3 h, then loaded into 0.25 mL straws and frozen in liquid nitrogen vapour. The SA1 and SA2 groups were higher plasma membrane and acrosome integrity (PMAI), high mitochondrial membrane potential (HMMP), plasma membrane integrity and motility compared to other groups (p < .05). It was observed that SA supplemented to the Tris extender significantly reduced DNA damage, and the lowest values were obtained especially in the SA1 and SA2 treatments (p < .05). Also, lowest MDA level was determined at the SA1 and this was statistically significant compared to SA4 and C (p < .05). In conclusion, it was revealed that SA added to Tris semen extender at 1 and 2 mM treatment doses increased progressive and total motility and preserved PMAI, plasma membrane integrity, HMMP and DNA integrity.

In this study, it was designed to reveal the effects of capsaicin on oxidative stress and freezability of ram semen. Ejaculates were taken from Sönmez rams and divided into five specimens and diluted with extender at different rates (4 mM, 2 mM, 1 mM, 500 µM) with and without capsaicin (control; C). At the end of the study, sperm motility and kinetic parameters, plasma membrane acrosome integrity (PMAI), mitochondrial membrane potential (MMP), DNA damage, oxidant and antioxidant parameters were analyzed. A decrease was observed in the groups containing capsaicin compared to the C in terms of progressive, total motility and kinetic parameters (p

Recently, the use of different herbal products as carbon sources instead of black and green tea in the preparation of traditional kombucha has been investigated. In this study, functional kombucha was prepared by adding Stevia rebaudiana Bertoni leaves, which have special organoleptic properties, to kombucha medium, and some properties of the beverage were analyzed. Tea blends were determined as 100% green tea (control = C), 75% green tea (GT) + 25% Stevia (ST), 50% GT + 50% ST, and 100% ST. On the 15th day of fermentation, gluconic acid (43.12 ± 0.01 g/L) was detected as dominant organic acid in GT75 + ST25 samples compared to group C (p < 0.05). According to physicochemical parameters that determine the drinkability properties of prepared teas, the best results were in GT25 + ST75 compared to group C (p < 0.05). It proved that the highest activity was in GT25 + ST75 on the 10th day in the groups that applied different antioxidant tests (DPPH, MCA, and CUPRAC). The antimicrobial activities of kombucha at 25, 50, 75, and 100% concentrations of GT and ST reached the highest levels in the GT25 + ST75 group in samples after 10 days of fermentation for all selected microorganisms. The results prove that GT25 + ST75 kombucha is a functional product with high drinkability on the 10th day of fermentation and also more beneficial for health due to the phenolic compounds from both green tea and Stevia. Stevia rebaudiana leaves can be suggested that be used as a new substrate and nitrogen source for kombucha production.

We conducted this study to determine the potential cryopreservative effects of different hesperidin (vitamin P; H) doses on ram semen after freeze-thawing. Semen samples were obtained from Sönmez rams using an artificial vagina. The samples were divided into six groups: control, 10, 50, 100, 250, and 500 µg/mL H (C, H10, H50, H100, H250, and H500, respectively). At the end of the study, sperm motility and kinetic parameters, acrosome integrity (AI), mitochondrial membrane potential (MMP), viability, lipid peroxidation levels (LPL), chromatin damage, oxidant parameters, and antioxidant parameters were assayed. None of the doses of H added to the semen extender showed any enhancing effects on progressive motility compared to C (p > 0.05). In fact, H500 had negative effects (p < 0.05). Moreover, AI was the highest at the H10 dose, while LPL values were the lowest at the same dose (p < 0.05). The doses of H10 and H50 added to the Tris extender medium showed positive effects on sperm cell chromatin damage. Consequently, we can say that H doses used in this study are not effective on semen progressive motility, but the H10 dose is effective on AI and chromatin damage by reducing LPL.