192
M. R. Nikolic et al.
(Bhayani et al. 2016). The role of trehalose on the dynamics and structural stabilization of PC was investigated by neutron scattering (Koeper et al. 2008). In addition,
Minic et al. (2018a) demonstrated a mutual protective effect of complexed PCB and
BSA against free radical attack using antioxidant assays.
8.7 PBPs-Derived Natural and Synthetic (Chromo)Peptides
Early studies of structure and/or configuration of PBP chromophores were performed
on chromopeptides and provided the means for the development of methods for their
purification. Rabier and Vijayalakshmi (1983) digested PC with pepsin and obtained
good separation of chromopeptides on histidyl-Sepharose gels based on histidinetetrapyrrole interactions. Chromopeptides from pepsin digests of PC were purified by
chromatography and isoelectrofocusing and, after photoisomerization, chromophore
configuration was characterized by ‘H NMR spectroscopy (Thümmler and Rüdiger
1983). In the study of Wedemayer et al. (1992), PBPs were digested by pepsin,
chromopeptides were purified by chromatography, and bilin groups were identified
by absorption, fluorescence,
1 H NMR, and MS.
Although multiple studies investigated biological activities of peptides produced
by enzymatic hydrolysis of whole algal biomass or isolated whole algal proteins
(Ovando et al. 2018), only a few of them focused on the bioactivities of
(chromo)peptides obtained from purified PBPs. In several studies, in addition to
the identification of bioactive peptides, some of the peptides were synthesized and
tested for bioactivity. Kim et al. (2018) identified PBPs by proteomics and, based on
obtained amino acid sequences, synthesized 13 PBPs-derived peptides which were
tested for their anti-cancer activity effect in vitro. Minic et al. (2016) digested PC
by pepsin in simulated gastric fluid, separated chromopeptides by chromatography,
and analyzed chromopeptides by MS. Sequences of chromopeptides were determined by manual de novo sequencing and confirmation of sequences was done by
analysis of MS2 and MS3 spectra of parent ions and pure PCB. They also tested
chromopeptides for antioxidant and metal-chelating activities, as well as for the
protection of human erythrocytes from free radical-induced hemolysis and cytotoxic
effect on HeLa and Caco-2 cells. Oh et al. (2018) separated whole algal proteins
on 2D PAGE, digested PE band by trypsin, and after identification by MS, synthesized PYP peptide and tested its effect in hippocampal neuron cell culture. Wu et al.
(2017) hydrolyzed PE by pepsin and purified the hydrolysate by gel permeation
and reversed-phase chromatography. Two peptides with the highest angiotensinconverting enzyme inhibitory activity were determined with the Edman degradation method, followed by the synthesis of peptides with the same sequences. Xu
et al. (2018) generated PC-derived peptides by limited trypsin hydrolysis, grafted
hydrolysate to N-succinyl chitosan by microbial transglutaminase and tested them
for antioxidant and anti-cancer activity on HeLa and L929 mouse fibroblast cell lines.
M. R. Nikolic et al.
(Bhayani et al. 2016). The role of trehalose on the dynamics and structural stabilization of PC was investigated by neutron scattering (Koeper et al. 2008). In addition,
Minic et al. (2018a) demonstrated a mutual protective effect of complexed PCB and
BSA against free radical attack using antioxidant assays.
8.7 PBPs-Derived Natural and Synthetic (Chromo)Peptides
Early studies of structure and/or configuration of PBP chromophores were performed
on chromopeptides and provided the means for the development of methods for their
purification. Rabier and Vijayalakshmi (1983) digested PC with pepsin and obtained
good separation of chromopeptides on histidyl-Sepharose gels based on histidinetetrapyrrole interactions. Chromopeptides from pepsin digests of PC were purified by
chromatography and isoelectrofocusing and, after photoisomerization, chromophore
configuration was characterized by ‘H NMR spectroscopy (Thümmler and Rüdiger
1983). In the study of Wedemayer et al. (1992), PBPs were digested by pepsin,
chromopeptides were purified by chromatography, and bilin groups were identified
by absorption, fluorescence,
1 H NMR, and MS.
Although multiple studies investigated biological activities of peptides produced
by enzymatic hydrolysis of whole algal biomass or isolated whole algal proteins
(Ovando et al. 2018), only a few of them focused on the bioactivities of
(chromo)peptides obtained from purified PBPs. In several studies, in addition to
the identification of bioactive peptides, some of the peptides were synthesized and
tested for bioactivity. Kim et al. (2018) identified PBPs by proteomics and, based on
obtained amino acid sequences, synthesized 13 PBPs-derived peptides which were
tested for their anti-cancer activity effect in vitro. Minic et al. (2016) digested PC
by pepsin in simulated gastric fluid, separated chromopeptides by chromatography,
and analyzed chromopeptides by MS. Sequences of chromopeptides were determined by manual de novo sequencing and confirmation of sequences was done by
analysis of MS2 and MS3 spectra of parent ions and pure PCB. They also tested
chromopeptides for antioxidant and metal-chelating activities, as well as for the
protection of human erythrocytes from free radical-induced hemolysis and cytotoxic
effect on HeLa and Caco-2 cells. Oh et al. (2018) separated whole algal proteins
on 2D PAGE, digested PE band by trypsin, and after identification by MS, synthesized PYP peptide and tested its effect in hippocampal neuron cell culture. Wu et al.
(2017) hydrolyzed PE by pepsin and purified the hydrolysate by gel permeation
and reversed-phase chromatography. Two peptides with the highest angiotensinconverting enzyme inhibitory activity were determined with the Edman degradation method, followed by the synthesis of peptides with the same sequences. Xu
et al. (2018) generated PC-derived peptides by limited trypsin hydrolysis, grafted
hydrolysate to N-succinyl chitosan by microbial transglutaminase and tested them
for antioxidant and anti-cancer activity on HeLa and L929 mouse fibroblast cell lines.