Chemistry Journal of Moldova

https:/doi.org/10.19261/cjm.2022.946   

 

Abstract (PDF)
Graphical Abstract: The composition of the lipophilic and hydrophilic extracts from the Feteasca Neagra ground seeds, grown in three different vineyards, was studied. The physicochemical indicators of the seeds, the oil quality indicators and the total content of polyphenols and flavonoids in the extracts were determined.  Some phenolic and flavanol constituents were identified and quantified using reversed-phase HPLC by gradient-elution. The Trolox equivalent antioxidant capacity assay proved the increased antioxidant activity of the hydrophilic extracts, with the highest DPPH• scavenging effect of almost 91.70 and 93.81%, an equivalent of 281.66 and 288.27 µM/L Trolox. It was concluded that the seeds recovered from Feteasca Neagra by-products are a rich source of functional compounds, with significant antioxidant properties. 


 

DOI: http://dx.doi.org/10.19261/cjm.2020.701   

 

Abstract (PDF)
Graphical Abstract: The concentrations of the accumulated heavy metals such as cadmium, lead, copper, mercury, zinc, and chromium have been determined in the muscles, gills and liver of the fish species of Clupea pallasii, Macolor niger and Pristipomoides filamentosus collected from the waters of the South Pacific Ocean around Lautoka in Fiji. Overall, the contents of heavy metals in all the samples were below the permissible limits, except for chromium that is slightly higher than the limit set by Food and Agriculture Organization of the United Nations and World Health Organization regulations, respectively. As anticipated, the muscles are still near the lowest concentration of all metal concentration. Significant variations in heavy metal concentrations were found between different tissues within each species of fish.


 

DOI: http://dx.doi.org/10.19261/cjm.2017.438   

 

Abstract (PDF)
Graphical Abstract: Avocado seeds starch was investigated after the modification with lactic acid using thermogravimetry and differential thermal analysis, differential scanning calorimetry, X-ray powder diffraction and scanning electron microscopy. After the modification, there was a decrease in the thermal stability of the starch, also the parameters measured by differential scanning calorimetry showed lower values. There was no difference in the morphology of the granules, which presented an oval and rounded shape. 



 

 

Abstract (PDF)
Graphical Abstract: The purpose of this research was to investigate the impact of indigenous starter culture capable to synthesize exopolysaccharides (EPSs) on physicochemical properties of yoghurt. Two starter cultures, EPS-producing and non-EPS-producing, were developed from the autochthonous lactic acid bacteria strains by pairwise combining Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus strains. In the present study the ropy strain of Streptococcus thermophilus CNMN LB-50 was incorporated in EPS-producing starter culture. The microstructure, viscosity, EPS amount, structural properties and syneresis of yoghurt samples were assessed. It has been established that the EPS-producing starter culture provided a reduction of structural degradation and increased degree of structural recovery after deformation. Besides, it was observed that the use of EPS synthesized starter culture in yoghurt production restrains the syneresis of the gel.

 

 

DOI: dx.doi.org/10.19261/cjm.2015.10(2).11

Graphical Abstract:  Procymidone was chosen as the model compound and its phototransformation was followed under sunlight irradiation. The main photodegradation products on silica is 3,5-dichloroaniline and 3,5-diclorphenilisocyanate. The use of ammonium ferric citrate enhances the degradation of the procymidone.

DOI: dx.doi.org/10.19261/cjm.2015.10(1).04

Graphical Abstract:  In young wines potassium hydrogen tartrate is always present in supersaturating concentration and crystallizes spontaneously. The aim of this study is to obtain kinetic parameters, which explain the stability of young wines during the stabilization treatments. The kinetic and equilibrium parameters were evaluated and discussed. According to the obtained experimental results, the optimal regime for production and stabilization of young wines has been established.

DOI: dx.doi.org/10.19261/cjm.2015.10(1).05

Graphical Abstract:  The present work was undertaken to study the effect of the treatment temperature on the potassium bitartrate stability and composition of young wines. The thermodynamic parameters, namely ∆G°, ∆H°, ∆S° were calculated to predict the nature of potassium hydrogen tartrate (KHT) precipitation. According to the achieved results, the exothermal nature and thermodynamical feasibility of KHT precipitation in young wines were established. Based on thermodynamics, negative ∆G°, ∆H° values and positive ∆S° value give a spontaneous KHT process at lower temperatures.