STUDY ON THE DYNAMICS OF SOME BIOACTIVE ELEMENTS FROM BEE POLLEN EXTRACTS

A.-Al. Prelipcean, Otilia Bobiş, St. Lazăr

Abstract
Analyses carried out have followed the determination of the amount of total polyphenols, flavanols, total flavonoids and antioxidant activity of bee pollen extracts harvested by collectors from Moldova. These determinations were performed according to different conditions: time, temperature and light. Two methanolic extracts have been used different in the methanolic solvent concentration used: 96% and 80%. Analyses were performed on fresh pollen extract, kept a week and kept two weeks, at 4°C, 20°C, the presence or absence of natural light. We have detected fluctuations in the quantities of compounds followed, both in relation to storage conditions and depending on the solvent used. The amounts of total polyphenols detected had mean values between 27.13 and 29.90 mg GAE / g pollen for extract 1 (solvent methanol concentration 96%) and between 23.56 and 27.67 mg GAE / g pollen for extract 2 (solvent methanol concentration 80%). Quantities of flavanols values were between 8.93 and 7.43 mg QE / g pollen (extract 1), and between 4.95 and 5.92 mg QE / g pollen (extract 2), describing a general downward dynamic. Total flavonoids recorded were between 20.44 and 28.00 mg QE / g pollen (extract 1), and between 16.17 and 19.50 mg QE / g pollen (extract 2). The antioxidant activity determined was between 24.18 and 14.24% inhibition (extract 1), and between 26.71 and 19.90% inhibition (extract 2).

Key words: pollen extract, dynamic, polyphenols, flavonoids, antioxidant activity

STUDIU PRIVIND DINAMICA UNOR ELEMENTE BIOACTIVE DIN EXTRACTE DE POLEN APICOL

A.-Al. Prelipcean, Otilia Bobiş, St. Lazăr

Rezumat
Analizele efectuate au urmarit determinarea în timp si diferite conditii de temperatura si lumina a cantitatii de polifenoli totali, flavone, flavonoide totale si a activitatii antioxidante a unor extracte polinice obtinute din polen apicol, recoltat cu ajutorul colectoarelor din zona Moldovei. S-au utilizat doua extracte metanolice, diferite prin concentratia solventului metanolic utilizat: 96% si 80%. Analizele au fost efectuate pe extract polinic proaspat, pastrat 1 saptamâna si pastrat 2 saptamâni; la 4°C, 20°C; prezenta sau absenta luminii naturale. S-au detectat fluctuatii în cantitatile de compusi urmariti, atât în functie de conditiile de pastrare cât si în functie de solventul utilizat. Cantitatile de polifenoli totali detectate au avut valori medii cuprinse între 27,13 si 29,90 mg GAE/g polen pentru extractul 1 (solvent metanolic de 96% concentratie) si între 23,56 si 27,67 mg GAE/g polen pentru extractul 2 (solvent metanolic de 80% concentratie). Dinamica rezultata a fost una în general ascendenta. Valorile cantitatilor de flavone au fost cuprinse între 8,93 si 7,43 mg QE/g polen (extract 1), respectiv între 4,95 si 5,92 mg QE/g polen (extract 2), descriind o dinamica în general descendenta. Flavonoidele totale au înregistrat valori cuprinse între 20,44 si 28,00 mg QE/g polen (extract 1), respectiv între 16,17 si 19,50 mg QE/g polen (extract 2). Dinamica descrisa a fost una în general ascendenta. Activitatea antioxidanta determinata a avut valori cuprinse între 24,18 si 14,24 % inhibitie (extract 1), respectiv între 26,71 si 19,90 % inhibitie (extract 2). Dinamica descrisa a fost una descendenta.

Cuvinte cheie: extract polinic, dinamica, polifenoli, flavonoide, activitate antioxidanta