Investigation of common chemical components and inhibitory effect on GES-type beta-lactamase (GES22) in methanolic extracts of Algerian seaweeds

HOUCHI, Selma/0000-0002-6922-709X; SANDALLI, Cemal/0000-0002-1298-3687WOS: 000458468100008PubMed: 30393116This study aimed to investigate the total phenolic content (TPC), the identification of the common compounds by HPLC-ESI-MS and HPLC-ESI-MS-TOF and the inhibitory effects against class A-type beta-lactamase (GES-22 variant, produced recombinantly) in methanolic extracts (MEs) of four Algerian seaweeds [Ulva intestinalis, Codium tomentosum, Dictyota dichotoma and Halopteris scoparia]. the TPC varied among the four species, ranging between 0.93 +/- 0.65 and 2.66 +/- 1.33 mg GAEs/g DW. C.tomentosum had higher total phenol content than other seaweeds while, all of them inhibited uncompetitively GES-22 activity in a dose-dependent manner. Nitrocefin was used as chromogenic substrate to evaluate the inhibitory effect on GES-22. the methanolic extract of D.dichotoma exhibited significant inhibitory effect on GES-22 (IC50 = 13.01 +/- 0.046 mu g/mL) more than clavulanate, sulbactam and tazobactam (classical beta-lactam inhibitors) (IC50 = 68.38 +/- 0.17 mu g/mL, 52.68 +/- 0.64 mu g/mL, and 29.94 +/- 0.01 mu g/mL, respectively). IC50 of the other ME of U.intestinalis, C.tomentostum, and H.scoparia were 16.87 +/- 0.10 mu g/mL, 16.54 +/- 0.048 mu g/mL, and 25.72 +/- 0.15 mu g/mL, respectively. Except H. scoparia, other three seaweed extracts showed almost two times or more inhibition on GES-22. Furthermore, four common compounds in these MEs were identified, alpha-linolenic acid (C18:3 omega 3), linoleic acid (C18:2 omega 6), oleic acid (C18:1 omega 9), the eicosanoid precursors "arachidonic acid" (C20:4 omega 6). Baicalein (C15H10O5) was identified in U.intestinalis and D.dichotoma seaweeds. the fact that all seaweed extracts inhibited the GES-22 better than commercial samples makes these seaweeds candidate for discovering new inhibitors against beta-lactamases. Besides that, they contain important components with potential health benefits

A Distinct Anti-EBV DNase Profile in Patients with Undifferentiated Nasopharyngeal Carcinoma Compared to Classical Antigens

Nasopharyngeal cancer (NPC) is a prevalent type of cancer that often takes the form of undifferentiated carcinoma in the Maghreb region. It affects people of all ages. NPC diagnosis, mainly based on detecting Epstein-Barr virus (EBV), has not been well evaluated in North Africa. We compared the classical EBV serological tests using indirect immunofluorescence to the detection of EBV DNase antibodies by immunoblot in Algerian NPC patients. Significant variations were observed among different age groups of patients regarding the presence of VCA-IgA antibodies (0–14 and ≥30 years old, p p p p < 0.05). Differences were also noted in the titers of IgA anti-VCA and anti-EA antibodies across the three age groups. Some patients under the age of 30 with detectable IgG anti-VCA antibodies had undetectable IgA anti-VCA antibodies. These patients had a strong anti-DNase IgA response. However, older individuals had a higher level of anti-DNase IgG. Before treatment, children had strong DNase reactivity as indicated by specific IgA antibodies. Young adults had high IgA anti-DNase response, but the elderly (90.9%) had a lower response for these antibodies. Following therapy, the children retained high levels of IgA anti-DNase antibodies, and 66% of the young adults demonstrated robust antibody reactivity against DNase. In contrast, IgG responses to anti-DNase were low in children. This study demonstrated the utility of anti-DNase responses in the diagnosis and prognosis of NPC