Ion Valeriu Caraba

Dr. Ion Valeriu Caraba


Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 September 2025 in Biology
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NGNicolae Adrian Giurginca
Nicolae Adrian Giurginca
Marioara Nicoleta FilimonMarioara Nicoleta Filimon
Marioara Nicoleta Filimon
DGDumitrescu Gabi
Dumitrescu Gabi
IPIoan Pet
Ioan Pet
Elena PeţElena Peţ
Elena Peţ
ICIon Valeriu Caraba
Ion Valeriu Caraba
The low profitability of small-scale dual-purpose (milk–meat) farming has caused the decline of Tsurcana sheep, making hormonal reproductive optimization essential to sustain Tsurcana sheep farming. We aimed to identify an effective protocol for out-of-season estrous induction in Tsurcana micro-farms. Five protocols were tested in multiparous ewes under free-range conditions (n = 100; 20/group): T1—prostaglandin F2α (PGF2α) on day 9/gonadotropin-releasing hormone (GnRH) on day 12; T2—PGF2α on day 9/pregnant mare serum gonadotropin (PMSG) on day 11; T3—PGF2α + PMSG on day 9/GnRH on day 12; T4—PGF2α on day 12/PMSG on day 13; T5—PMSG on day 13. The fluorogestone acetate (FGA) sponges were removed on day 9 (T1–T3), day 12 (T4), or day 13 (T5). The estrous responses (70–100%) mainly occurred 36–48 h post-sponge removal, with no differences between protocols or time points. The sponge losses (≤10%) were similar among groups. The occurrence of vaginitis differed significantly between the groups (p = 0.008) and was restricted to the long-duration treatments (T4 and T5; ≤10%). Singleton births predominated, the twinning rate was modest (highest in T1–T3), and no multiple births occurred. The lambing, singleton, twinning, and prolificacy rates, as well as birth weights, showed no significant differences between the groups. The estrous responses correlated strongly with the pregnancy, lambing, and singleton rates (Kendall’s τ = 0.82, p < 0.05). Cost analysis identified T1 as the most efficient protocol. Short-duration sponge retention combined with PGF2α and GnRH (T1) provides the optimal reproductive results for sustainable Tsurcana micro-farming.

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VBVanessa Bolchis
Vanessa Bolchis
DLDelia Luca-Abrudan
Delia Luca-Abrudan
Ramona DumitrescuRamona Dumitrescu
Ramona Dumitrescu
Atena GaluscanAtena Galuscan
Atena Galuscan
Marioara Nicoleta FilimonMarioara Nicoleta Filimon
Marioara Nicoleta Filimon
DJDaniela Elisabeta Jumanca
Daniela Elisabeta Jumanca
Oral biofilms are complex polymicrobial communities involved in the development of dental caries and periodontal diseases. Chemical antiseptics are commonly used as adjuncts to mechanical plaque control; however, their antimicrobial efficacy varies depending on composition and mechanism of action. The aim of this study was to comparatively evaluate the antimicrobial and antibiofilm activities of four commercially available dental products (Corsodyl, Ozosan, HybenX, and Elugel) against a broad spectrum of oral microorganisms. This in vitro study included Gram-positive and Gram-negative bacterial strains, comprising both reference strains and clinical isolates, as well as Candida albicans. Antimicrobial activity was assessed using the disc diffusion assay, while antibiofilm activity was evaluated using a crystal violet microplate assay. All experiments were performed in triplicate. Statistical analysis was conducted using two-way ANOVA followed by Tukey’s post hoc test (p < 0.05). All tested products exhibited antimicrobial activity. Inhibition zones ranged from 9 to 56 mm for Gram-positive bacteria, 12 to 38 mm for Gram-negative bacteria, and 13 to 43 mm for Candida albicans. Two-way ANOVA revealed a significant effect of the dental product (p < 0.001), while incubation time was not significant (p > 0.05). HybenX showed the highest antimicrobial efficacy, while chlorhexidine-based products demonstrated consistent activity. Antibiofilm inhibition exceeded 80% for several strains. Dental antiseptics exhibit significantly different antimicrobial and antibiofilm profiles, highlighting the importance of appropriate product selection in oral biofilm control.

22 October 2025 in Foods
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ANAlexandru Nan
Alexandru Nan
MMMihai Mitulețu
Mihai Mitulețu
DGDumitrescu Gabi
Dumitrescu Gabi
ICIon Valeriu Caraba
Ion Valeriu Caraba
IPIoan Pet
Ioan Pet
Marioara Nicoleta FilimonMarioara Nicoleta Filimon
Marioara Nicoleta Filimon
Honey is a traditional remedy, with its biologically active compounds being responsible for its properties. The aim of this study was to characterize linden honey from a physico-chemical point of view as well as its antimicrobial and antibiofilm potential. Two samples of linden honey with different origins were subjected to physico-chemical analyses, including the determination of water content, impurities, dry matter, acidity, pH, reducing sugar content, total phenol content, flavonoids, antioxidant potency by DPPH, and mineral content. The microbiological analysis involved determining the inhibition rates of microbial growth and the antibiotic capacity of linden honey against ten standardized bacterial strains and five bacterial strains isolated from patients. The analyzed linden honey can be characterized based on physico-chemical parameters as having a slightly increased water content, moderate acidity, rich in antioxidants, and a balanced pH. The average concentrations of macroelements and microelements in the honey samples showed that potassium was the dominant mineral element, followed by calcium and magnesium. The heavy metal content was consistent with European and international standards. The chemical content of linden honey influenced its antimicrobial and antibiofilm potential. In Gram-positive bacteria, inhibition rates were between 70.83 and 91.28% (sample A) and 71.14–90.16% (sample B) when applying concentration c1. For Gram-negative bacteria, values ranged between 63.91 and 78.30% (sample A) and 46.56–90.92% (sample B) at concentration c1. In bacterial strains isolated from patients, the inhibition rate values were between 75.42 and 85.69% (sample A) and 78.31–86.22% (sample B) when applying concentration c1. The antimicrobial and antibiofilm potential was highlighted in all bacterial strains studied, with differences occurring depending on the concentration of honey tested and the type of bacterial strain studied.

8 June 2026 in Foods
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Journal Article
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ANAlexandru Nan
Alexandru Nan
Marioara Nicoleta FilimonMarioara Nicoleta Filimon
Marioara Nicoleta Filimon
MMMihai Mitulețu
Mihai Mitulețu
DGDumitrescu Gabi
Dumitrescu Gabi
ICIon Valeriu Caraba
Ion Valeriu Caraba
DPDaniela Puscasiu
Daniela Puscasiu
Honey has been appreciated for its medicinal properties since ancient times; it is known as a powerful antimicrobial agent, and as a result of the increase in antibiotic resistance of various bacterial strains, honey began to be used in complementary therapies to combat microbial infections. The study aimed to identify the antimicrobial potential of two honey varieties (Acacia honey and polyflora honey) with different botanical and geographical origins on standardized bacterial strains or isolated from patients, some of which showed antibiotic resistance. The physicochemical parameters of the honey varieties analyzed were: water content, impurities, pH of honey, acidity, mineral content, reducing sugar content, total phenol content, and antioxidant capacity (DPPH). The antibacterial potential of the honey varieties was assessed based on tests to determine cell viability and the capacity to inhibit biofilm formation. The Gram-positive strains studied were Staphylococcus aureus (ATCC25923), Staphylococcus aureus MRSA (ATCC43300), Streptococcus pneumoniae (ATCC49619), and the Gram-negative strain was Escherichia coli (ATCC25922). In addition, bacterial strains isolated from the patients were Staphylococcus aureus, Staphylococcus aureus MRSA, Streptococcus pneumoniae, and Escherichia coli. The results of the microbiological tests were correlated with the physicochemical parameters, suggesting that the content of polyphenolic compounds with antioxidant activity and acidic pH may contribute to the antimicrobial potential of honey. Also, statistical analyses indicated significant differences regarding the antimicrobial potential of honey on Gram-positive versus Gram-negative bacteria, standardized versus isolated bacteria from patients, but also for antibiotic-resistant bacteria compared to the other strains studied.

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ICIon Valeriu Caraba
Ion Valeriu Caraba
Luminita CrisanLuminita Crisan
Luminita Crisan
Marioara Nicoleta FilimonMarioara Nicoleta Filimon
Marioara Nicoleta Filimon
This study evaluated the effects of different doses of the herbicide fluroxypyr on soil microbial communities under controlled laboratory conditions. Specific enzymatic activities ((dehydrogenase (DA), urease (UA), catalase (CA), phosphatase (PA)) and quantitative variations in bacterial and fungal populations were measured regarding key physico-chemical soil parameters (temperature, pH, electrical conductivity, moisture, organic matter, ammonium, nitrate nitrogen, and available phosphate content). The effects of the herbicide on the targeted parameters were dose- and time-dependent. Fluroxypyr induced a clear decrease in DA, CA, and PA during the first 14 days after administration, while UA showed a decrease in the first 7 days, followed by a slight increase starting on day 14, closely related to the applied dose. Microbial populations decreased in direct relation to the fluroxypyr dose. Organic matter content exhibited a positive correlation with DA, UA, CA, as well as with microbial populations. In addition, three natural compounds structurally similar to fluroxypyr were identified via 3D virtual screening, demonstrating potential herbicidal activity. Fluroxypyr can alter soil metabolic activity and disrupt microbial communities, thereby affecting soil fertility. Used as a reference in 3D screening, fluroxypyr helped identify three natural compounds with potential herbicidal activity as safer alternatives to synthetic herbicides.

9 April 2025 in Romanian Journal of Oral Rehabilitation
Verified
Journal Article
Open access
ANAlexandru Nan
Alexandru Nan
MCMarioara Nicoleta Caraba
Marioara Nicoleta Caraba
DPDaniela Puscasiu
Daniela Puscasiu
CVCristian Sebastian Vlad
Cristian Sebastian Vlad
LTLaria-Maria Trusculescu
Laria-Maria Trusculescu
GDGabi Dumitrescu
Gabi Dumitrescu
Aim of the study: Honey has been historically recognized as a traditional therapeutic agent for microbial infections due to its biologically active compounds, which confer antibacterial, anti-inflammatory, and antioxidant properties. This study aims to chemically characterize and evaluate the antimicrobial potential of linden honey sourced from an ecological apiary in western Romania. Materials and methods: Physico-chemical analyses were conducted to determine key parameters, including impurity levels, water content, acidity, pH, and reducing sugar concentration, all of which were found to be within the established regulatory standards. The total phenolic content was assessed to confirm the antioxidant properties of the honey. Microbiological evaluations were performed to determine inhibition rates and biofilm formation inhibition capacity against both Gram-positive and Gram-negative bacterial strains, including standard strains and those isolated from patients. The anti-biofilm potential was assessed using 2,3,5-triphenyl-tetrazolium chloride (TTC), while anti-biofilm activity was quantified via the crystal violet assay. Results: The antimicrobial and anti-biofilm effects of linden honey were observed across all tested bacterial strains, with variations depending on the honey concentration and bacterial type. The honey exhibited both bacteriostatic and bacteriolytic effects, influenced by concentration and bacterial susceptibility. Notably, the antibacterial efficacy differed when tested on standardized bacterial strains, patient-isolated strains, and antibiotic-resistant strains. Conclusions: The chemical composition of linden honey played a significant role in determining its antimicrobial and anti-biofilm efficacy. The findings support the potential of linden honey as a natural antimicrobial agent, with its effects being concentration-dependent and influenced by bacterial strain characteristics. These results contribute to the growing body of research on the therapeutic applications of honey in combating bacterial infections and biofilm formation.