Laura Stan | USAMV Cluj Napoca (original) (raw)

Papers by Laura Stan

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2008

Royal jelly present quality of the biological and physiological exception of the reason for which... more Royal jelly present quality of the biological and physiological exception of the reason for which is marketed widely is being used in various industries, such as the pharmaceutical, food (nutritional supplements) and cosmetics companies (M?rghita?, 2005). This paper contents a summery about physical-chemical composition of fresh and lyophilized royal jelly. Queen bees are made, not born, and their feeding with royal jelly is the key to that process. Royal jelly (RJ) is a yellowish and creamy secretion from hypo pharyngeal and mandibular glands of young worker bees (Apis mellifera L.) to feed all larvae for the first three days of their life and the queen bee for both her larval life and adulthood. The physical-chemical composition of pure royal jelly are analyzed by determining moisture, free acidity, pH, ash; and for lyophilized royal jelly are analyzed by determining free acidity, pH, ash. In literature 10-HDA content is the criteria of royal jelly quality analysis and it is a fre...

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2007

Many research studies are mentioned in scientific literature regarding the quality parameters of ... more Many research studies are mentioned in scientific literature regarding the quality parameters of monofloral honeys. The purpose of this study is to make a physico-chemical characterization of three monofloral types of honey and honeydew in order to realize a general profile of these honeys. Analytical methods applied for this research were elaborated by International Honey Commission in 2002 and are used in European Community. Physico-chemical analyses were developed for all 24 samples consisting in ash, water, color and sugars content.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, Dec 15, 2008

Royal jelly present quality of the biological and physiological exception of the reason for which... more Royal jelly present quality of the biological and physiological exception of the reason for which is marketed widely is being used in various industries, such as the pharmaceutical, food (nutritional supplements) and cosmetics companies (Mărghitaş, 2005). This paper contents a summery about physicalchemical composition of fresh and lyophilized royal jelly. Queen bees are made, not born, and their feeding with royal jelly is the key to that process. Royal jelly (RJ) is a yellowish and creamy secretion from hypo pharyngeal and mandibular glands of young worker bees (Apis mellifera L.) to feed all larvae for the first three days of their life and the queen bee for both her larval life and adulthood. The physical-chemical composition of pure royal jelly are analyzed by determining moisture, free acidity, pH, ash; and for lyophilized royal jelly are analyzed by determining free acidity, pH, ash. In literature 10-HDA content is the criteria of royal jelly quality analysis and it is a freshness parameter (

Propolis is one of the best natural antibiotic, with high amounts of polyphenols, derived from pl... more Propolis is one of the best natural antibiotic, with high amounts of polyphenols, derived from plant’s resins from where the bees collect, mix with own substances and wax, and preserve it in the hive. High variability among propolis samples was noticed, depending on the geographical origin, plant source, harvesting procedures and methods of evaluation 1 . One of the major problems in labeling the propolis that is commercially available is the real bioactive compounds concentration. The study was aimed to evaluate the in vitro antibacterial activity and the chemical composition of different commercially available propolis based products (tinctures, ethanolic, glycolic and hydroglycolic extracts, products for veterinary and human use). Spectrophotometric and chromatographic determinations were used to characterize the propolis products. The in vitro antibacterial activity was evaluated against reference strains of Staphylococcus aureus, Staphylococcus pseudintermedius, Bacillus cereus, Enterococcus faecalis, Salmonella enteritis, Salmonella typhimurium and Escherichia coli using the disc diffusion assay. The results indicated intense antibacterial properties in case of both tinctures and ethanolic extracts, especially against Bacillus cereus , Staphylococcus aureus and Staphylococcus pseudintermedius. While the inhibition zone diameters were significantly smaller for the Gram negative bacteria, no efficacy was recorded towards Enterococcus faecalis. Total polyphenols varied from 18-26% and flavonoids (6-10%) were determined in all samples. The total amount of polyphenols and flavonoids depended both on the concentration of propolis in the extracts and the solvent type used for extract preparations and its concentration. These data underline the complex chemical composition and antimicrobial potential of certain propolis based products.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca: Horticulture, Nov 27, 2015

Smoked plums and pears are highly appreciated in Romanian food culture as traditional healthy des... more Smoked plums and pears are highly appreciated in Romanian food culture as traditional healthy dessert. Safety concerns about smoked fruits led to the application of slow dehydration at low temperatures (SDLT) as gentle method to prologue the product shelf life. The aim of this study was to evaluate the consumers' expectations and perception both prior and after tasting of dried plums and pears obtained by SDLT. A questionnaire of 15 questions with 5 point Hedonic scale was addressed to regular consumers of dried fruits (N=97). Alongside with willingness to buy and perception of product quality, the respondent's expectations were evaluated before tasting the product (for product general appearance, colour and expected taste) and after tasting (for taste and consistency). Promising results were obtained for both pears and plums, thus concluding that the respondents are open to accept new processing methods for traditional products as long as there is a beneficial sensorial advantage in the perceived quality of the product.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2009

Propolis samples from Transylvanian stationary apiaries were collected during 2004-2007 and were ... more Propolis samples from Transylvanian stationary apiaries were collected during 2004-2007 and were analyzed for total phenolics and antioxidant activity. DPPH was employed as free stable radical for evaluation of propolis radical scavenging activity (RSA), inhibitory concentration IC 50 and propolis's content in antioxidant compounds. Correlation between propolis composition and antioxidant activity was performed. Analyzed propolis presented about 3% flavones/flavonols, 4% flavanones/dihydro-flavonols, 23% total phenolics. RSA values of propolis were 17±4%. There is an indirect relation between RSA and IC50. Therefore, propolis with high RSA values has low IC50 (under 2mg/ml). Correlation coefficients between RSA, IC50 and phenolics were calculated, and a positive correlation was found between phenolics and antioxidant activity.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2007

In this article there are two methods presented for determination of 2 groups of flavonoids: flav... more In this article there are two methods presented for determination of 2 groups of flavonoids: flavone/flavonols (FF)-AlCl 3 , and flavanones/dihydroflavonols (FD)-2,4-dinitrophenylhidrazine. Together they sum up the total flavonoids (FvT) in propolis. Romanian propolis taken into analysis had an amount of 4% flavone/flavonols, 6% flavanones/dihydroflavonols and about 10% total flavonoids typical for propolis derived from Populus sp. Statistical correlation between data (FF, FD, FvT) obtained by sonication and by maceration present no significance difference between results.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2009

Bulletin UASVM Animal Science and Biotechnologies, 66 (1-2)/2009 Print ISSN 1843-5262; Electronic... more Bulletin UASVM Animal Science and Biotechnologies, 66 (1-2)/2009 Print ISSN 1843-5262; Electronic ISSN 1843-536X ... Transylvanian Propolis from 7 Counties Qualitative and Quantitative Analysis of Phenolics ... Cristina M. MIHAI, Liviu Al. MĂRGHITAŞ, Daniel DEZMIREAN, ...

DOAJ (DOAJ: Directory of Open Access Journals), Dec 1, 2015

Food consumption habits could be determined by various factors: cultural identity, area of reside... more Food consumption habits could be determined by various factors: cultural identity, area of residence, economical and physical access, lifestyle. This article presents the preliminary results obtained from a quantitative study in rural regions of Transylvania. The research focused on the investigation of food consumption frequency for major food groups but also on the provenience of food consumed within the households. A number of 1190 subjects was investigated between February and May 2015. The results show a high consumption rate for food products derived from cereals. Pork and chicken meat is frequently preferred in rural households, a possible explanation being the tradition of consuming these types of meat as well as facile accessibility. A high consumption rate of fresh fruits and vegetables is a positive aspect shown by the study, the quantity consumed being covered by the internal household production. Further analysis of the collected data is required in order to identify the barriers between tradition and modernity and to create a food consumption pattern of rural households in Transylvania.

Food and Chemical Toxicology, Dec 1, 2013

We aimed at investigating the antioxidant, antiinflamatory, antiapoptotic and antigenotoxic effec... more We aimed at investigating the antioxidant, antiinflamatory, antiapoptotic and antigenotoxic effects of a 30 Romanian Propolis (RP) extract in two concentrations (RP1 3 mg, respectively RP2 1.5 mg polyphenols/ 31 cm 2), topically administered, either prior to or after UVB exposure, in a Swiss mouse model. Our results 32 showed that both concentrations of RP extract, independent of the time of administration, significantly 33 attenuated the malondialdehyde (MDA) formation and restored glutathione peroxidase (GPx) activity. 34 However, the 8-hydroxy-2-deoxy-guanosine (8-oxo-dG), nitric oxide (NO) and glutathione (GSH) levels 35 were not influenced by UVB exposure and RP treatment. Interleukin (IL)-6 levels were significantly 36 decreased by RP treatment, both before and after UVB-exposure. RP2 extract, in both regimens, signifi-37 cantly reduced the epidermal hyperplasia and dermal inflammation, whereas RP1 pre-treatment dimin-38 ished only the dermal inflammation. The effect of our RP extract in terms of reduction of sunburn cell 39 formation and of activated caspase-3 and TUNEL-positive cells was observed in both subsets of the exper-40 iment, RP2 having a slightly better protective effect as compared to RP1. The antigenotoxic effect of RP 41 was demonstrated by significantly reduced cyclobutane pyrimidine dimers (CPDs) formation. Our results 42 suggest that RP extract might be a potential chemopreventive candidate by modulation of multiple UVB-43 induced signaling pathways in skin.

Wageningen Academic Publishers eBooks, May 18, 2015

The purpose of this paper work is the sensorial analysis of bread types (graham type and bread wi... more The purpose of this paper work is the sensorial analysis of bread types (graham type and bread with eggplant and oregano) in order to fit the products in quality class and establish consumer preferences. It's been used the method for assessing the average number of points (20) and hedonic scale method

Oxidative Medicine and Cellular Longevity, Feb 27, 2020

Currently, one of the central problems in cancer management is the relapse of disease following c... more Currently, one of the central problems in cancer management is the relapse of disease following conventional treatments, yet few therapeutic agents targeting resistance and tolerance exist. Propolis is known as a healing agent since ancient times. Therefore, over time, its curative properties have kept the interest of scientists, thus leading permanently to investigations of its other possible undiscovered effects. In this context, current experiments were performed to establish the chemopreventive potential of propolis extract (PE) (1.05 mg/kg BW/day) in N-methyl-N-nitrosourea-(MNU-) induced rat mammary tumors. MNU-inoculated/PEtreated rats had tumors of different physical attributes compared with control rats MNU-inoculated. The number of developed tumors (mean 49% versus 100%), incidence (mean 49% versus 100%), multiplicity (1.8 versus 3.7 (p < 0:001)), tumor volume (mean 10 cm 3 versus 16 cm 3 (p < 0:001)), and weight of the tumor mass (mean 7.42 g versus 9.00 g (p < 0:05)) were noted. The numbers of grade I tumors recorded for MNU-inoculated rats were 24 (Group 1) and 7 (Group 2) for MNU-induced/PEtreated rats. In the serum of rats MNU-inoculated/PE-treated were found higher levels of antioxidative enzymes (SOD, CAT, and GPx) than in MNU-induced. Taken together, these data indicate that propolis could be a chemopreventive agent against MNU-induced mammary carcinogenesis.

Foods, Feb 12, 2019

Fresh water availability is considered highly risky because it is a finite resource, and a defici... more Fresh water availability is considered highly risky because it is a finite resource, and a deficiency in water leads to numerous economic and environmental issues. Agriculture is one of the main consumers of fresh water in practices such as irrigation and fertilization. In this context, the main objectives of this study were (i) to determine the descriptive sensory profiles of four almond types grown using different irrigation strategies and (ii) to study their acceptance in a cross-cultural study (Romania and Spain). Consumers' willingness to pay for hydroSOS almonds was also evaluated. The four irrigation strategies evaluated were a control sample, two samples grown under regulated deficit irrigation strategies (RDI), and a sample grown under a sustained deficit irrigation strategy (SDI). The main conclusion was that neither descriptive nor affective sensory results showed significant differences among treatments. These findings should encourage farmers to reduce their water usage by demonstrating that sensory quality was not significantly affected by any of the studied treatments, compared to the control. Regarding willingness to pay, both Spanish and Romanian consumers were willing to pay a higher price for the hydroSOS almonds.

Journal of Comparative Pathology, 2017

Introduction: Mammary tumours are one of the most common tumours in female dogs worldwide. This i... more Introduction: Mammary tumours are one of the most common tumours in female dogs worldwide. This investigation presents the protective degree of long-term day-today administration of propolis in the MNU-induced rat mammary tumour model. Materials and Methods: Thirty-day-old juvenile female Spra-gueeDawley rats were utilized. Methyl-nitroso-urea (MNU) was used to induce mammary tumours, while propolis was used as a chemopreventive agent. The female rats were assigned to four groups: group 1, inoculated with 55 mg MNU/kg body weight (BW) intraperitoneally; group 2, inoculated with MNU and received feed with propolis (15 droplets of alcoholic extract of propolis/rat/day); group 3 inoculated with saline and received feed with propolis (15 droplets of propolis/rat/day); and group 4, inoculated with saline. The experiment continued for 290 days. A complete necropsy examination was performed for each animal, followed by histological assessment of the mammary tumours. Results: All rats of group 1 developed tumours compared with seven of 10 rats in group 2. The mammary tumour induction ratio was 90.24% in group 1 and 90% in group 2. The average mammary tumour number/rat was 3.7 AE 2.75 in group 1 versus 1.8 AE 1.39 in group 2 (P !0.05). A difference was noticed in the average of mammary tumour volume (16.68 AE 33.32 in group 1 versus 10.76 AE 17.17 in group 2; P !0.05) and mammary tumour mass compared with final BW (9.00 AE 10.86 in group 1 versus 7.42 AE 11.43 in group 2; P !0.05). Conclusions: Daily administration of propolis in the diet of rats with MNU-induced mammary tumours induced a significant drop in the tumour occurrence compared with the control group.

Agronomy

This study examined the effect of simultaneous fermentations of Saccharomyces cerevisiae and Pich... more This study examined the effect of simultaneous fermentations of Saccharomyces cerevisiae and Pichia kluyveri, Lactobacillus plantarum and Oenococcus oeni on the chemical composition of apple cider from two apple varieties—Topaz and Red Topaz. Analytical techniques (HPLC-RID, HPLC-VWD, GC/MS, GC/FID, HPLC-DAD ESI+) were employed to analyze glucides, organic acids, volatile compounds, amino acids and phenolic compounds, respectively. Statistical analysis and and PCA were conducted to assess the correlations among samples based on the compounds identified. In the mixed fermentations, such as Saccharomyces cerevisiae + Lactobacillus plantarum and Saccharomyces cerevisiae + Oenococcus oeni, the amount of lactic acid was higher compared to the other samples, thus proving the effectiveness of malolactic fermentation simultaneous to alcoholic fermentation. The fermentation of Saccharomyces cerevisiae + Pichia kluyveri resulted in the formation of greater amounts of certain volatile compound...

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2008

28 declared honeydew honey samples were collected from different Transylvanian areas directly fro... more 28 declared honeydew honey samples were collected from different Transylvanian areas directly from the beekeepers (24 samples) or from supermarket (4 samples). Physico-chemical parameters as well as microscopic analysis were done in order to authenticate the honeydew honey from this part of Romania. The results of electrical conductivity, ash and mineral content, honeydew honey elements demonstrated that from the analyzed samples 7 were real honeydew honeys, 9 were mixture of multifloral and honeydew honeys and 12 were multifloral honeys. High quantity of honey, ddeclared and sold as honeydew honey do not correspond to the EU requirements for honeydew honey. To improve this situation, a better control by the authorities and certified laboratories, is needed

The result of the long evolutionary process formed, by natural selection, variable races and ecot... more The result of the long evolutionary process formed, by natural selection, variable races and ecotypes which are biological and ecological differentiated. The Romanian, Apis mellifera carpatica is the most adapted and the most efficient species at the local conditions. Morphometric measurements were the major criteria for classification described by Ruttner (1988) and are the basis of our study. In this way 8 morphometric characters of honeybees from Transylvanian region were measured. The data obtained show that the honeybees’ ecotype genes are mixed due to the migratory beekeeping.

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2009

The chemical composition of propolis was investigated. This type of investigations was extremely ... more The chemical composition of propolis was investigated. This type of investigations was extremely valuable with respect to propolis standardization and practical applications in therapy. In this study are two methods presented for two flavonoids group determination: flavone/flavonols (FF)–AlCl3, and flavanones/dihydroflavonols (FD)–2,4-dinitrophenylhidrazine.Transylvanian propolis taken into analysis had an amount of 6.61% flavone/flavonols, 3.02% flavanones/dihydroflavonols and about 10% total flavonoids typical for propolis derived from Populus sp. Total phenolic content was measured by the Folin-Ciocalteu procedure using a mixture of Pinocembrin and Galangin as internal standards. The analyzed samples of propolis presented an average of 35.60% of phenolic compounds. The extraction of active principles from propolis was performed and the average of the extraction yield was found to be 60% ± 7.7%.