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Glucose-, galactose- and lactose-containing photosensitizers based on derivatives of chlorophyll a and bacteriochlorophyll a were synthesized with the use of [3+2] cycloaddition between sugar azides and triple bond derivatives of chlorins and bacteriochlorins. Unlike bacteriochlorin cycloimide, chlorin was detected to form a Cu-complex during the click reaction. An approach to the synthesis of metal-free glycosylated chlorins was developed with the use of "protection" by Zn²⁺ cation and subsequent demetalation. It is based on the action of alkynyl chlorin e₆ derivative Zn-complex, which is resistant to the substitution by copper cation. Bacteriochlorin p cycloimide conjugate with per-acetylated β-D-lactose was obtained and shown to become water-soluble after unblocking of the lactose hydroxy functions. NMR studies allowed for the elucidation of structure, tautomeric form and conformation of the obtained compounds.

A regioselective synthesis of glycoconjugates based on bacteriochlorophyll a and lactose derivatives has been carried out. The conjugation was achieved via 1,3-dipolar cycloaddition of bacteriochlorins containing a terminal triple bond and a lactose azide derivative. The conjugates obtained in this way had one or two disaccharide fragments attached to pyrrol A, the exocyclic imide ring of the tetrapyrrolyc macrocycle, or to both positions. Exhaustive NMR analysis by 1D and 2D NMR experiments (¹H-¹H COSY, TOCSY, ROESY, ¹H-¹³C HSQC, HMBC, and ¹H-¹⁵N HMBC) allowed us to determine the structures and configurations of the glycoconjugates obtained. A bioassay of the glycoconjugates using the Hep2 cell line showed that the highest efficiency was observed for the glycosylated bacteriopurpurinimide containing a lactose residue at pyrrole ring A.

The abilities of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus to decrease lactose content in milk after different light treatments have been compared in this study. Each one of cultures was treated by visible daily light, linear non-coherent polarized light or kept in dark. After fermentation lactose concentration was measured by ultrasound milk analyzer Lacto Scan. Experimental results show the decrease of lactose concentration in a range of 37,5% - 40,35%, dependant to the treatments and durations. There are significant differences in lactose concentration (p < 0,01) by cultures treated 40, 50 and 60 minutes, in relation to the kind of treatments. Each one of treatments in duration 30 show no statistical differences in lactose concentration (p = 0,05). Diagram of experimental results presents a percent of decrease in lactose concentration as a logarithmic function of the energy impute in the case of linear non-coherent polarized light.