Articole ştiinţifice

Research on cryopreservation of ram semen

2026-06-22T10:17:26Z

Research on cryopreservation of ram semen DARIE, Grigorie; CIBOTARU, Elena; BRADU, Nina; DJENJERA, Irina The research was carried out on semen obtained from Karakul and Tigaie rams. There was reviled a high individual variability of sexual behaviour in Bethaimer and Sulfoc ejaculate efficacy in the cryopreservation process, the dilution medium for cryopreservation of the seminal material was proposed. The evaluation of the results of ram semen freezing supposed the evaluation of the ejaculates obtained from rams of various breeds, the cryopreservation, the storage of the semen and its use for the sowing of the sheep and the stock of semen material in the gene banks.

Comparative analysis of cryopreserved ram sperm parameters depending on the dilution medium

2026-06-22T08:57:30Z

Comparative analysis of cryopreserved ram sperm parameters depending on the dilution medium DARIE, Grigore; CIBOTARU, Elena; DJENJERA, Irina; BRADU, Nina To improve the effectiveness of long-term sperm storage outside the animal’s body, it is necessary to enhance the protective media that help reduce the impact of cryodamaging factors on sperm. In this study, sperm from Assaf breed rams was used. Sperm was collected from the rams twice a week using an artificial vagina, which ensured high-quality material. For analysis, ejaculates with at least 70% motility and a concentration of 2,0 to 2,5 billion sperm per milliliter were selected. The aim of the study was to compare the parameters of cryopreserved sperm depending on the synthetic media used: GTJ, STJ+MP, and STJ+IMB-2. This allowed for the determination of the most suitable extender to ensure a higher fertilization rate. During the study, the main parameters of cryopreserved sperm were analyzed, including motility, percentage of pathological sperm forms, plasma membrane integrity (based on the hypoosmotic swelling test results), and acrosome integrity. The highest values were achieved with samples diluted with the STJ+IMB-2 medium. In this group, the following results were obtained: motility – 54,0±0,4%, velocity (VAP) – 91,8±3,4%, VSL – 75,5±3,9%, VCL – 132,0±3,8%, percentage of anomalies – 16,75%, acrosome integrity – 24,15±0,31%, and plasma membrane integrity was 65,6±0.7%. The obtained data suggest that the STJ+IMB-2 medium provided the most effective protection for sperm during cryopreservation compared to other media such as GTJ and STJ+MP. These results highlight the importance of selecting an appropriate medium to optimize cryopreservation processes and improve fertilization rates.

Reducing sulphite consumption in wines by applying bioprotective yeasts

2026-06-21T16:53:34Z

Reducing sulphite consumption in wines by applying bioprotective yeasts CUPCEA, Nicolai; STURZA, Rodica Consumer demand for “low-sulfite” wines requires alternative microbiological preservation strategies. Non-Saccharomyces yeasts (Metschnikowia pulcherrima and Torulaspora delbrueckii) suppress spoilage organisms through bioprotection (iron chelation, nutrient competition, oxygen depletion) without compromising fermentation. Bioprotective yeasts operate through an elegant ecological principle: inoculated directly into fresh grape must at the prefermentation stage, they rapidly colonize the available microbial niche before indigenous spoilage organisms can establish themselves. Operating at low prefermentation temperatures (10-16°C), these non-Saccharomyces yeasts competitively consume fermentable sugars and nutrients, produce inhibitory metabolites, trigger oxygen-dependent stress responses that suppress acetic acid bacteria and lactic acid bacteria, and establish mechanisms of cell-contact inhibition. Essentially, they perform this protective action without initiating alcoholic fermentation – a role reserved for later inoculated Saccharomyces cerevisiae strains, which take over once the ethanol concentration exceeds the ethanol tolerance threshold (~5% v/v) of the bioprotectors. This study reports the results of field tests conducted under Moldovan conditions, validating the efficacy of bioprotector yeasts on white grape musts from the Codru region (Glera and Fetească Regală varieties). The results demonstrated a 32–50% reduction in sulfites compared to traditional methods. Volatile acidity levels (0.43–0.44 g/L) remained at approximately 40% of the EU quality threshold, demonstrating the successful suppression of acetic acid bacteria and other spoilage microorganisms during the critical pre-fermentative stage. The author would like to thank the Institutional Project, subprogram 020405 “Optimizing food processing technologies in the context of the circular bioeconomy and climate change”, Bio-OpTehPAS, being implemented at the Technical University of Moldova.

Postprandial glycemic response to thermally processed rice: experimental basis for metabolic predictability and stability assessment

2026-06-21T16:51:30Z

Postprandial glycemic response to thermally processed rice: experimental basis for metabolic predictability and stability assessment VÎRLAN, Anna; SIMINIUC, Sergiu; ȚURCANU, Dinu; SIMINIUC, Rodica Postprandial glycemic response is strongly influenced not only by food composition but also by technological processing conditions applied prior to consumption. Rice represents an appropriate experimental model for investigating how domestic thermal processing affects metabolic responses. The aim of this study was to experimentally evaluate the effect of cooking duration on postprandial glycemic response and to establish an in vivo experimental basis for assessing metabolic variability, stability, and predictability. Four rice varieties differing in structural characteristics (three refined varieties and one whole-grain variety) were analysed under two cooking regimes: recommended cooking time and prolonged cooking (+10 min), simulating thermal overprocessing. An in vivo study involving ten healthy participants was conducted. Glycemic response was assessed using glycemic index (GI), incremental area under the glycemic curve (iAUC₀–₁₂₀), postprandial glycemic dynamics (0–120 min), and glycemic load (GL) of a standard 300 g portion. Statistical evaluation was performed using two-factor ANOVA to determine the effects of rice variety and cooking duration. Results showed systematic increases in GI and iAUC₀–₁₂₀ for refined rice varieties following prolonged cooking, indicating enhanced starch digestibility and increased glycemic exposure. In contrast, whole-grain long-grain rice exhibited a differentiated response characterized by reduced iAUC values and maintenance of moderate glycemic load despite extended thermal treatment. ANOVA analysis confirmed significant effects of both variety (F=48.84, p<0.001) and cooking duration (F=7.14, p=0.009), as well as a significant interaction between factors, demonstrating that technological processing effects are variety-dependent. Extended cooking also reduced interindividual variability for some varieties, suggesting partial convergence of metabolic responses. Cooking duration acts as a critical technological determinant of both intensity and stability of postprandial glycemic response. The experimental protocol proved sensitive to technological modification, providing a validated basis for predictive modelling of glycemic response. The research was supported by Institutional Project, subprogram 020405 “Optimizing food processing technologies in the context of the circular bioeconomy and climate change”, Bio-OpTehPAS, being implemented at the Technical University of Moldova.