Of three beta-galactosidases from Aspergillus oryzae, Kluyveromyces lactis and Bacillus sp., used for the production of low-content galacto- oligosaccharides (GOS) from lactose, the latter produced the highest yield of trisaccharides and tetrasaccharides. GOS production was enhanced by mixing beta-galactosidase glucose oxidase. The low-content GOS syrups, produced either by beta-galactosidase alone or by the mixed enzyme system, were subjected to the fermentation by Kluyveromyces marxianus, whereby glucose, galactose, lactose and other disaccharides were depleted, resulting in up to 97% and 98% on a dry weight basis of high-content GOS with the yields of 31% and 32%, respectively.

β-Galactosidase was immobilized on chitosan using tris(hydroxymethyl)phosphine (THP) as a coupling agent to produce galactooligosaccharides (GOS) from lactose. Both the THP-immobilized and the free enzymes were maximally achieved at pH 5.0 and the optimal temperature was 55• C. The residual activities for the THP-immobilized enzyme and the free enzyme were 75 and 25%, respectively, after being incubated in 0.1 mol dm −3 sodium acetate buffer (pH 5.0) at 55 • C for 13 days. The formation of GOS was catalyzed by free and THP-immobilized β-galactosidase from lactose. The yield of GOS produced by the free enzyme from the lactose solution (36%, w/v) at 55• C was 43% on a dry weight basis, which was similar to the 41% GOS yield produced by the THP-immobilized enzyme system.

A partially purified beta-fructofuranosidase from Aspergillus japonicus was covalently immobilized on to chitosan beads using either glutaraldehyde or tris(hydroxymethyl)phosphine (THP) as a coupling agent. Compared with the glutaraldehyde-immobilized and the free enzyme, the THP-immobilized enzyme had the highest thermal stability with 78% activity retained after 12 days at 37 degrees C. The THP-immobilized enzyme also had higher reusability than that immobilized by glutaraldehyde, 75% activity was retained after 11 batches (or 11 days) at 37 degrees C for the THP immobilized enzyme system. Less yield (48%) of fructooligosaccharides (FOS) were produced by the THP-immobilized enzyme compared with the free enzyme system (58%) from 50 (w/v) sucrose at 50 degrees C.

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Viral reactivation was previously reported after severe acute respiratory syndrome coronavirus‐2 (SARS-CoV-2) infection but was seldom documented after SARS-CoV-2 vaccination, except varicella-zoster virus and cytomegalovirus. Here, we present a case of reactive Epstein–Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) and thrombosis with thrombocytopenia syndrome after receiving SARS-CoV-2 mRNA vaccination. Antiplatelet factor 4 antibody was detected, and the bone marrow study showed hemophagocytosis and was positive in the immunohistochemistry staining for EBV-encoded small nuclear RNAs and negative staining for CD3 and CD56 markers of small lymphocytes. The high percentage of CD38 high/HLA-DR+ cells among CD8+ T cells further confirmed HLH. After intravenous administration of immunoglobulin, the clinical symptoms, D-dimer level, fibrinogen, platelet count, EBV-DNA titer, and anti-PF4 level were all improved. Further investigation into the pathogenesis of vaccine-associated EBV reactivation, such as TNF-α, interleukin-1β (IL-1β), and interleukin-6 (IL-6), is warranted.