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Recovery of laccase from processed Hericium erinaceus (Bull.:Fr) Pers. fruiting bodies in aqueous two-phase system

Rajagopalu D, Show PL, Tan YS, Muniandy S, Sabaratnam V, Ling TC

J Biosci Bioeng, 2016 Sep;122(3):301-6.
PMID: 26922478 DOI: 10.1016/j.jbiosc.2016.01.016

The feasible use of aqueous two-phase systems (ATPSs) to establish a viable protocol for the recovery of laccase from processed Hericium erinaceus (Bull.:Fr.) Pers. fruiting bodies was evaluated. Cold-stored (4.00±1.00°C) H. erinaceus recorded the highest laccase activities of 2.02±0.04 U/mL among all the processed techniques. The evaluation was carried out in twenty-five ATPSs, which composed of polyethylene glycol (PEG) with various molecular weights and potassium phosphate salt solution to purify the protein from H. erinaceus. Optimum recovery condition was observed in the ATPS which contained 17% (w/w) PEG with a molecular weight of 8000 and 12.2% (w/w) potassium phosphate solution, at a volume ratio (VR) of 1.0. The use of ATPS resulted in one-single primary recovery stage process that produced an overall yield of 99% with a purification factor of 8.03±0.46. The molecular mass of laccases purified from the bottom phase was in the range of 55-66 kDa. The purity of the partitioned laccase was confirmed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).
Recovery of lignin peroxidase from submerged liquid fermentation of Amauroderma rugosum (Blume & T. Nees) Torrend using polyethylene glycol/salt aqueous two-phase system

Jong WYL, Show PL, Ling TC, Tan YS

J Biosci Bioeng, 2017 Jul;124(1):91-98.
PMID: 28319022 DOI: 10.1016/j.jbiosc.2017.02.008

Amauroderma rugosum is a wild mushroom species widely distributed in tropics and is classified under the class of Basidiomycetes. Basidiomycetes are well-known for their abilities of producing lignocellulolytic enzymes such as lignin peroxidase (LiP), laccase (Lac) and manganese peroxidase (MnP). Different factors such as nutrient sources, incubation period and agitation affect the production of lignocellulolytic enzymes. The A. rugosum produced LiP in the medium supplemented with potato dextrose broth (PDB), 0.5% yeast and 1.0% saw dust at 26.70±3.31 U/mL. However, the LiP activity was increased to 106.32±5.32 U/mL when supplemented with 150 μm of copper (CuSO4). The aqueous two-phase system (ATPS) is a simple, rapid and low cost method for primary extraction and recovery of LiP. A total of 25 systems made from five different molecular weights of polyethylene glycol (PEG)/dipotassium hydrogen phosphate (K2HPO4) were tested. PEG 600 produced the highest top phase purification factor (PFT) of 1.33±0.62 with yield of 72.18±8.50%. The optimization of the ATPS parameters, such as volume ratio VR, pH and crude enzyme loading are the factors controlling the phase partition. Our results showed that significant improvement (PFT of 6.26±2.87 with yield of 87.31±3.14%) of LiP recovery can be achieved by optimized the parameters.
Solid-substrate fermentation of wheat grains by mycelia of indigenous species of the genus Ganoderma (higher Basidiomycetes) to enhance the antioxidant activities

Subramaniam S, Sabaratnam V, Kuppusamy UR, Tan YS

Int J Med Mushrooms, 2014;16(3):259-67.
PMID: 24941167

Species of the genus Ganoderma are a cosmopolitan wood decaying white rot fungi, which has been used by the Asians for therapeutic purposes for centuries. In the present study, solid-substrate fermentation (SSF) of wheat grains (Triticum aestivum L.) was carried out with indigenous Ganoderma australe (KUM60813) and G. neo-japonicum (KUM61076) selected based on ethnomycological knowledge. G. lucidum (VITA GL) (a commercial strain) was also included in the study. Antioxidant activities of the crude ethanol and aqueous extracts of the fermented and unfermented wheat grains were investigated by ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), diphenyl-1-picryl-hydrazyl (DPPH) free radical scavenging ability, and lipid peroxidation assay. Among the six mycelia extracts tested, the ethanol extract from wheat fermented with KUM61076 mycelia showed the most potent antioxidant activities, whereas the ethanol extract of wheat grains fermented with KUM60813 mycelia has a good potential in protecting frying oils against oxidation. Total phenolic content (TPC) in the ethanol extracts were higher than that in the aqueous extract. The wheat grains fermented with G. australe (KUM60813) and G. neo-japonicum KUM61076 have greater antioxidant potential compared to the commercially available G. lucidum (VITA GL). The antioxidant activities of the mycelia extracts had a positive correlation with their phenolic contents. Thus phenolic compounds may play a vital role in the antioxidant activities of the selected Ganoderma spp.
Surface Decoration of Selenium Nanoparticles by Proteins from the Culinary-Medicinal Shiitake Mushroom, Lentinus edodes (Agaricomycetes), for Enhanced Fibrinolytic Activity

Ali SM, Raman J, Lakshmanan H, Ling TC, Phan CW, Tan YS, et al.

Int J Med Mushrooms, 2018;20(11):1021-1030.
PMID: 30806227 DOI: 10.1615/IntJMedMushrooms.2018028307

Lentinus edodes (shiitake mushroom) has exhibited fibrinolytic activity. We synthesized and characterized selenium nanoparticles (SeNPs) using protein precipitated from the mushroom. We also investigated the fibrinolytic activity of the SeNPs. The proteins from a crude extract of L. edodes were recovered through the use of aqueous 2-phase separation, and these we used as the capping agent in SeNP biosynthesis. We characterized the SeNPs using UV-visible spectrophotometry, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), particle size distribution analysis, and Fourier transform infrared spectroscopy (FT-IR). The fibrinolytic capability of the SeNPs was tested through an in vitro fibrin plate assay. The UV-visible spectra showed maximal absorbance at 220 nm. FESEM images showed that the SeNPs were dispersed and did not clump. The TEM images revealed a spherical shape and average size of the SeNPs. The particle size distribution analysis confirmed the mean size of the SeNPs at 64.53 nm. A strong signal for the presence of selenium was observed in the EDX analysis. The FT-IR spectrum revealed the involvement of protein functional groups in the reduction of sel-enite. Overall, the SeNPs capped with protein from shiitake mushroom were effective as an in vitro fibrinolytic agent.
Fulltext Taxonomic and phylogenetic re-evaluation of Mycena illuminans

Chew AL, Tan YS, Desjardin DE, Musa MY, Sabaratnam V

Mycologia, 2013 Sep-Oct;105(5):1325-35.
PMID: 23709573 DOI: 10.3852/13-009

Mycena illuminans Henn. is described and re-evaluated based on recently collected material from peninsular Malaysia, providing comprehensive descriptions, illustrations and photographs. In addition to morphological data, axenic monokaryon and dikaryon cultures were established to provide data on culture morphology and the mating system of the species. Molecular sequences data from the nuclear large subunit (LSU) gene also are presented, confirming that M. illuminans is not a synonym of Mycena chlorophos.
The impact of pharmacist interventions, follow-up frequency and default on glycemic control in Diabetes Medication Therapy Adherence Clinic program: a multicenter study in Malaysia

Lim PC, Tan HH, Mohd Noor NA, Chang CT, Wong TY, Tan EL, et al.

J Pharm Policy Pract, 2023 Jul 05;16(1):83.
PMID: 37408067 DOI: 10.1186/s40545-023-00583-8

BACKGROUND: Pharmacist's involvement in optimizing medication adherence among diabetic patients has been implemented for over a decade. Diabetes Medication Therapy Adherence Clinic (DMTAC) was set up to educate diabetic patients, monitor treatment outcomes, and manage drug-related problems. While evidence shows that pharmacist-led DMTAC was effective in reducing HbA1c, there was limited data regarding the impact of different intervention types and default to follow-up on glycemic control.
AIM: To assess the impact DMTAC on glycemic control and the difference in glycemic control between hospital and health clinic settings as well as defaulter and non-defaulter. In addition, the impact of pharmacist's interventions, DMTAC follow-up frequencies, and duration of diabetes on glycemic control were also determined.
METHODS: A retrospective study was conducted among diabetes patients under DMTAC care between January 2019 and June 2020 in five hospitals and 23 primary health clinics. Patients' demographics data, treatment regimens, frequencies of DMTAC visits, defaulter (absent from DMTAC visits) and types of pharmacists' intervention were retrieved from patients' medical records and electronic database. HbA1c was collected at baseline, 4-6 months (post-1), and 8-12 months (post-2).
RESULTS: We included 956 patients, of which 60% were females with a median age of 58.0 (IQR: 5.0) years. Overall, the HbA1c reduced significantly from baseline (median: 10.2, IQR: 3.0) to post-1 (median: 8.8, IQR: 2.7) and post-2 (median: 8.3, IQR: 2.6%) (p