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Quinoline, Indole, and Isogranatanine Alkaloids from Malayan Leuconotis eugeniifolia

Tan YS, Ng MP, Tan CH, Tang WK, Sim KS, Yong KT, et al.

J Nat Prod, 2024 Feb 23;87(2):286-296.
PMID: 38284153 DOI: 10.1021/acs.jnatprod.3c00960

Nine new alkaloids, eugeniinalines A-H (1-8) and (+)-eburnamenine N-oxide (9), comprising one quinoline, six indole, and two isogranatanine alkaloids, were isolated from the stem-bark extract of the Malayan Leuconotis eugeniifolia. The structures and absolute configurations of these alkaloids were established based on the analysis of the spectroscopic data, GIAO NMR calculations, DP4+ probability analysis, TDDFT-ECD method, and X-ray diffraction analysis. Eugeniinaline A (1) represents a new pentacyclic quinoline alkaloid with a 6/6/5/6/7 ring system. Eugeniinaline G (7) and its seco-derivative, eugeniinaline H (8), were the first isogranatanine alkaloids isolated as natural products. The known alkaloids leucolusine (10) and melokhanine A (11) were found to be the same compound, based on comparison of the spectroscopic data of both compounds, with the absolute configuration of (7R, 20R, 21S). Eugeniinalines A and G (1 and 7) showed cytotoxic activity against the HT-29 cancer cell line with IC50 values of 7.1 and 7.2 μM, respectively.
Fulltext Polymorphism of HLA and Susceptibility of Breast Cancer

Aboulaghras S, Khalid A, Makeen HA, Alhazmi HA, Albratty M, Mohan S, et al.

Front Biosci (Landmark Ed), 2024 Feb 05;29(2):55.
PMID: 38420797 DOI: 10.31083/j.fbl2902055

Breast cancer (BC) is the second most common malignancy in the world. Numerous studies have demonstrated the association between human leukocyte antigen (HLA) and cancer. The occurrence and development of BC are closely linked to genetic factors. Human leukocyte antigens G and E (HLA-G and HLA-E) are non-classical major histocompatibility complex (MHC) class I molecules. These molecules play an important role in immune surveillance by inhibiting the cytotoxic and natural killer T cells responsible for immune escape. The expression of HLA-G and HLA-E has been associated with several diseases, including tumors. The HLA system plays a key role in the escape of tumor cells from immune surveillance. This review aims to determine the correlation between BC susceptibility and HLA markers specific HLA alleles such as HLA-B07, HLA-DRB111, HLA-DRB113, and HLA-DRB115 are associated with an increased risk of developing BC. Furthermore, HLA-G mutations have been attributed to an elevated likelihood of metastasis in BC patients. Understanding the complex associations between the HLA system and BC development is critical for developing novel cancer prevention, detection, and treatment strategies. This review emphasizes the importance of analyzing HLA polymorphisms in the management of BC patients, as well as the urgent need for further research in this area.
Leveraging nitrogen occurrence in approved drugs to identify structural patterns

Masand VH, Al-Hussain S, Alzahrani AY, El-Sayed NNE, Yeo CI, Tan YS, et al.

Expert Opin Drug Discov, 2024;19(1):111-124.
PMID: 37811790 DOI: 10.1080/17460441.2023.2266990

BACKGROUND: The process of drug development and discovery is costly and slow. Although an understanding of molecular design principles and biochemical processes has progressed, it is essential to minimize synthesis-testing cycles. An effective approach is to analyze key heteroatoms, including oxygen and nitrogen. Herein, we present an analysis focusing on the utilization of nitrogen atoms in approved drugs.
RESEARCH DESIGN AND METHODS: The present work examines the frequency, distribution, prevalence, and diversity of nitrogen atoms in a dataset comprising 2,049 small molecules approved by different regulatory agencies (FDA and others). Various types of nitrogen atoms, such as sp3-, sp2-, sp-hybridized, planar, ring, and non-ring are included in this investigation.
RESULTS: The results unveil both previously reported and newly discovered patterns of nitrogen atom distribution around the center of mass in the majority of drug molecules.
CONCLUSIONS: This study has highlighted intriguing trends in the role of nitrogen atoms in drug design and development. The majority of drugs contain 1-3 nitrogen atoms within 5Å from the center of mass (COM) of a molecule, with a higher preference for the ring and planar nitrogen atoms. The results offer invaluable guidance for the multiparameter optimization process, thus significantly contributing toward the conversion of lead compounds into potential drug candidates.
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
Fulltext Investigating the Correlation between Electrolyte Concentration and Electrochemical Properties of Ionogels

Suen JW, Elumalai NK, Debnath S, Mubarak NM, Lim CI, Reddy Moola M, et al.

Molecules, 2023 Jul 04;28(13).
PMID: 37446854 DOI: 10.3390/molecules28135192

Ionogels are hybrid materials comprising an ionic liquid confined within a polymer matrix. They have garnered significant interest due to their unique properties, such as high ionic conductivity, mechanical stability, and wide electrochemical stability. These properties make ionogels suitable for various applications, including energy storage devices, sensors, and solar cells. However, optimizing the electrochemical performance of ionogels remains a challenge, as the relationship between specific capacitance, ionic conductivity, and electrolyte solution concentration is yet to be fully understood. In this study, we investigate the impact of electrolyte solution concentration on the electrochemical properties of ionogels to identify the correlation for enhanced performance. Our findings demonstrate a clear relationship between the specific capacitance and ionic conductivity of ionogels, which depends on the availability of mobile ions. The reduced number of ions at low electrolyte solution concentrations leads to decreased ionic conductivity and specific capacitance due to the scarcity of a double layer, constraining charge storage capacity. However, at a 31 vol% electrolyte solution concentration, an ample quantity of ions becomes accessible, resulting in increased ionic conductivity and specific capacitance, reaching maximum values of 58 ± 1.48 μS/cm and 45.74 F/g, respectively. Furthermore, the synthesized ionogel demonstrates a wide electrochemical stability of 3.5 V, enabling diverse practical applications. This study provides valuable insights into determining the optimal electrolyte solution concentration for enhancing ionogel electrochemical performance for energy applications. It highlights the impact of ion pairs and aggregates on ion mobility within ionogels, subsequently affecting their resultant electrochemical properties.
Fulltext In silico studies, X-ray diffraction analysis and biological investigation of fluorinated pyrrolylated-chalcones in zebrafish epilepsy models

Mohd Fahmi MSA, Swain P, Ramli AH, Wan Ibrahim WN, Saleh Hodin NA, Abu Bakar N, et al.

Heliyon, 2023 Feb;9(2):e13685.
PMID: 36852036 DOI: 10.1016/j.heliyon.2023.e13685

Epilepsy is the third most common known brain disease worldwide. Several antiepileptic drugs (AEDs) are available to improve seizure control. However, the associated side effects limit their practical use and highlight the ongoing search for safer and effective AEDs. Eighteen newly designed fluorine-containing pyrrolylated chalcones were extensively studied in silico, synthesized, structurally analyzed by X-ray diffraction (XRD), and biologically and toxicologically tested as potential new AEDs in zebrafish epilepsy in vivo models. The results predicted that 3-(3,5-difluorophenyl)-1-(1H-pyrrol-2-yl)prop-2-en-1-one (compound 8) had a good drug-like profile with binding affinity to γ-aminobutyric acid receptor type-A (GABAA, -8.0 kcal/mol). This predicted active compound 8 was effective in reducing convulsive behaviour in pentylenetetrazol (PTZ)-induced larvae and hyperactive movements in zc4h2 knockout (KO) zebrafish, experimentally. Moreover, no cardiotoxic effect of compound 8 was observed in zebrafish. Overall, pyrrolylated chalcones could serve as alternative AEDs and warrant further in-depth pharmacological studies to uncover their mechanism of action.
Eugeniifoline, a Pentacyclic Indole Alkaloid from Leuconotis eugeniifolia, and Configurational Revision of Synthetic Eugeniifoline Isolated from a Diversity-Enhanced Extract

Tan YS, Wong SK, Yong KT, Lim KH, Lim SH, Low YY

J Nat Prod, 2023 Jan 27;86(1):232-236.
PMID: 36651825 DOI: 10.1021/acs.jnatprod.2c00731

Eugeniifoline (1), a pentacyclic indole alkaloid with a five-membered ring E, was isolated for the first time as a natural product from the stem-bark extract of Leuconotis eugeniifolia. Eugeniifoline (1) was previously reported as a synthetic product from a diversity-enhanced extract, but with the configuration at C-21 reported as S (1a). The configuration at C-21 was revised to R as shown in 1, based on the NOE data, GIAO NMR calculations, and DP4+ probability analysis, as well as the TDDFT-ECD method.
Fulltext Genome Assembly and Analysis of the Flavonoid and Phenylpropanoid Biosynthetic Pathways in Fingerroot Ginger (Boesenbergia rotunda)

Taheri S, Teo CH, Heslop-Harrison JS, Schwarzacher T, Tan YS, Wee WY, et al.

Int J Mol Sci, 2022 Jun 30;23(13).
PMID: 35806276 DOI: 10.3390/ijms23137269

Boesenbergia rotunda (Zingiberaceae), is a high-value culinary and ethno-medicinal plant of Southeast Asia. The rhizomes of this herb have a high flavanone and chalcone content. Here we report the genome analysis of B. rotunda together with a complete genome sequence as a hybrid assembly. B. rotunda has an estimated genome size of 2.4 Gb which is assembled as 27,491 contigs with an N50 size of 12.386 Mb. The highly heterozygous genome encodes 71,072 protein-coding genes and has a 72% repeat content, with class I TEs occupying ~67% of the assembled genome. Fluorescence in situ hybridization of the 18 chromosome pairs at the metaphase showed six sites of 45S rDNA and two sites of 5S rDNA. An SSR analysis identified 238,441 gSSRs and 4604 EST-SSRs with 49 SSR markers common among related species. Genome-wide methylation percentages ranged from 73% CpG, 36% CHG and 34% CHH in the leaf to 53% CpG, 18% CHG and 25% CHH in the embryogenic callus. Panduratin A biosynthetic unigenes were most highly expressed in the watery callus. B rotunda has a relatively large genome with a high heterozygosity and TE content. This assembly and data (PRJNA71294) comprise a source for further research on the functional genomics of B. rotunda, the evolution of the ginger plant family and the potential genetic selection or improvement of gingers.
Dynamics of fungal and bacterial microbiome associated with green-mould contaminated sawdust substrate of Pleurotus pulmonarius (grey oyster mushroom)

Ponnusamy A, Ajis AH, Tan YS, Chai LC

J Appl Microbiol, 2021 Oct 12.
PMID: 34637602 DOI: 10.1111/jam.15327

AIMS: Green-mould contamination is identified as one of the challenges faced by mushroom cultivation industry globally which believed to be caused by Trichoderma spp.
METHODS AND RESULTS: To explore the dynamics of microbial population in mushroom substrate during commercial mushroom cultivation and how microbiota might play a role in green-mould contamination, we applied both culturing and targeted metagenomics approaches to identify microbiota in noncomposted sawdust substrates at different cultivation stages. The microbiological analysis showed that the green-mould contaminated substrates harboured higher total mesophilic bacteria count. The green-moulds isolated from the contaminated mushroom substrates were identified as Trichoderma pleurotum (n = 15; 93.8%) and Graphium penicillioides (n = 1; 6.3%). To our surprise, the targeted metagenomic analysis revealed that Graphium comprised 56.3% while Trichoderma consisted of only 36.1% of the total fungi population, suggesting that green-mould contamination might not be caused by Trichoderma alone, but also Graphium that grows very slowly in the laboratory.
CONCLUSION: It is worthwhile to note that G. penicillioides was also isolated in the early stages of mushroom cultivation, but not T. pleurotum. The results indicated that the structure and composition of the bacterial population in the mushroom substrate varied and the bacterial population shifted along the cultivation process.
SIGNIFICANCE AND IMPACT OF STUDY: This study revealed a possibility of G. penicillioides as an overlooked fungi causing green-mould contamination.
Effect of solvent pre-treatment on the physicochemical, thermal profiles and morphological behavior of Mangifera pajang seed fat

Norazlina MR, Tan YS, Hasmadi M, Jahurul MHA

Heliyon, 2021 Sep;7(9):e08073.
PMID: 34622074 DOI: 10.1016/j.heliyon.2021.e08073

In this work, the effect of solvent pre-treatment (hexane, petroleum ether and ethanol) on the physicochemical, thermal and morphology behavior of Mangifera pajang seed fat (MPSF) were investigated. Fat extraction was performed using Soxhlet method, and results showed that the yield, physicochemical, and crystalline structures of the MPSF were significantly (p < 0.05) influenced by the extraction solvents. Hexane gave the highest fat yield (7.67 %) with low unsaturation value (52.13 g iodine/g) compared with petroleum ether and ethanol. Hexane MPSF also had low oxidation rate (peroxide value of 1.1 mEq/g). Both non-stabilized and stabilized hexane MPSF showed a single melting endothermic peak at high temperature with onset, maximum peak and offset temperature of 16.23 ˚C-18.21 °C, 28.22 ˚C-31.25 °C and 34.85 ˚C-39.58 °C, respectively. Hexane MPSF crystallized rapidly at high temperature with single maximum peak starting at 16.51 ˚C-16.68 °C and ending at 0.23 ˚C-1.13 °C. In comparison with ethanol extract, hexane MPSF demonstrated a compact crystalline structure with a large densely packed center. Therefore, MPSF obtained from hexane presented better overall quality than those obtained from other extraction solvents. MPSF exhibited similar melting and morphological behavior to mango kernel fat and commercial cocoa butter. These results suggested that hexane was the best solvent for the extraction of MPSF. This fat also has the potential to be applied as a cocoa butter alternative fat or functional fat.
Angiosarcoma - a rare fatal cause of recurrent pericardial effusions

Ng BH, Tan YS, Pavitratha P, A Hing C, Zainul NH, Lim CH

Med J Malaysia, 2020 11;75(6):759-761.
PMID: 33219196

A 40-year-old man presented to the Hospital Sultanah Bahiyah, Alor Setar, Kedah, with constitutional and respiratory symptoms. Physical examination and echocardiogram demonstrated massive pericardial effusion. Patient required multiple attempts of pericardiocentesis due to recurrent pericardial effusion. Initial workup including pericardial fluids examination and computed tomography imaging did not reveal any apparent cause. Magnetic resonance imaging showed a suspicious mass infiltrating into the right atrium. Autoimmune screening was negative. Patient was subsequently treated as having tuberculous pericarditis. However, his disease progressed rapidly and he eventually passed away due to right atrial rupture. Postmortem revealed a ruptured right atrial tumour leading to massive haemothorax. Histopathological examination confirmed the diagnosis of primary pericardial angiosarcoma.
Diagnostic accuracy and ability to reduce unnecessary FNAC: A comparison between four Thyroid Imaging Reporting Data System (TI-RADS) versions

Tan L, Tan YS, Tan S

Clin Imaging, 2020 Sep;65:133-137.
PMID: 32470834 DOI: 10.1016/j.clinimag.2020.04.029

BACKGROUND: Thyroid Imaging Reporting Data System (TI-RADS) is used to characterize thyroid nodules while reducing unnecessary FNAC. Over the years, several versions of TI-RADS have been developed but there is no consensus on which TI-RADS is the best system. This study aimed to compare the diagnostic accuracy and ability of ACR TI-RADS, EU TI-RADS, K TI-RADS, AI TI-RADS to eliminate unnecessary FNAC.
METHODS: In this prospective study, thyroid nodules were characterized by using the four TI-RADS systems and US-guided FNAC was done for nodule with the highest ACR TI-RADS score. Correlation between TI-RADS and FNAC results were analyzed.
RESULTS: Out of 244 thyroid nodules, 100 nodules with either size <1 cm (43 nodules) non-diagnostic or inconclusive FNAC results (57 nodules) were excluded. Seven nodules (4.9%) were confirmed to be malignant on FNAC. K TI-RADS showed 100% sensitivity and NPV but the lowest specificity (40.2%). EU TI-RADS had the highest specificity (83.2%) but the lowest sensitivity (57.1%) and NPV (97.4%). ACR TI-RADS had an average sensitivity (85.7%) and NPV (98.6%). The specificity of ACR TI-RADS (51.1%) was lower than EU TI-RADS but higher than K TI-RADS. AI TI-RADS showed higher specificity (61.8% vs 51.1%, p
Fulltext New Species of Termitomyces (Lyophyllaceae, Basidiomycota) from Sabah (Northern Borneo), Malaysia

Sathiya Seelan JS, Shu Yee C, She Fui F, Dawood M, Tan YS, Kim MJ, et al.

Mycobiology, 2020;48(2):95-103.
PMID: 32363037 DOI: 10.1080/12298093.2020.1738743

The genus Termitomyces (Lyophyllaceae, Basidiomycota) is often associated with fungus-feeding termites (Macrotermitinae) due to their strong symbiotic relationships. The genus is widely found exclusively in certain regions of Africa and Asia. They are recognized as edible mushroom within Southeast Asia as well. But it is often misidentified based on morphology by the local communities especially in Malaysia for Chlorophyllum molybdites which is a highly poisonous mushroom. Thus, it is necessary to study the genus for Malaysia with the synergy of using both morphological and molecular identification. In this study, we aim to describe another new species as an addition to the genus Termitomyces found within Sabah, Malaysia. We generated two new sequences (nrLSU and mtSSU) for the new species and a total of 28 nrLSU and mtSSU sequences were retrieved from GenBank for the phylogenetic analysis using maximum likelihood and Bayesian inferences. We identified that the new collection from Sabah province is a new species and named as Termitomyces gilvus based on the termites found in the mound. A phylogeny tree made from the concatenated genes of LSU and mtSSU suggests that T. gilvus is closely related to T. bulborhizus from China. According to our results, the combination of molecular and morphology proved to be a robust approach to re-evaluate the taxonomic status of Termitomyces species in Malaysia. Additional surveys are needed to verify the species diversity and clarify their geographic distribution.
In vitro anti-bacterial and time kill evaluation of binuclear tricyclohexylphosphanesilver(I) dithiocarbamates, {Cy3PAg(S2CNRR')}2

Tan YJ, Tan YS, Yeo CI, Chew J, Tiekink ERT

J Inorg Biochem, 2019 03;192:107-118.
PMID: 30640150 DOI: 10.1016/j.jinorgbio.2018.12.017

Four binuclear phosphanesilver(I) dithiocarbamates, {cyclohexyl3PAg(S2CNRR')}2 for R = R' = Et (1), CH2CH2 (2), CH2CH2OH (3) and R = Me, R' = CH2CH2OH (4) have been synthesised and characterised by spectroscopy and crystallography, and feature tri-connective, μ2-bridging dithiocarbamate ligands and distorted tetrahedral geometries based on PS3 donor sets. The compounds were evaluated for anti-bacterial activity against a total of 12 clinically important pathogens. Based on minimum inhibitory concentration (MIC) and cell viability tests (human embryonic kidney cells, HEK 293), 1-4 are specifically active against Gram-positive bacteria while demonstrating low toxicity; 3 and 4 are active against methicillin resistant S. aureus (MRSA). Across the series, 4 was most effective and was more active than the standard anti-biotic chloramphenicol. Time kill assays reveal 1-4 to exhibit both time- and concentration-dependent pharmacokinetics against susceptible bacteria. Compound 4 demonstrates rapid (within 2 h) bactericidal activity at 1 and 2 × MIC to reach a maximum decrease of 5.2 log10 CFU/mL against S. aureus (MRSA).
Fulltext Expression and DNA methylation of SERK, BBM, LEC2 and WUS genes in in vitro cultures of Boesenbergia rotunda (L.) Mansf

Karim R, Tan YS, Singh P, Khalid N, Harikrishna JA

Physiol Mol Biol Plants, 2018 Sep;24(5):741-751.
PMID: 30150851 DOI: 10.1007/s12298-018-0566-8

The process of somatic embryogenesis and plant regeneration involve changes in gene expression and have been associated with changes in DNA methylation. Here, we report the expression and DNA methylation patterns of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK), BABY BOOM (BBM), LEAFY COTYLEDON 2 (LEC2) and WUSCHEL (WUS) in meristematic block of newly emerged shoots from rhizome, embryogenic and non-embryogenic calli, prolonged cell suspension culture, ex vitro leaf, and in vitro leaf of regenerated plants of Boesenbergia rotunda. Among all seven samples, based on qRT-PCR, the highest level of expression of SERK, BBM and LEC2 was in embryogenic callus, while WUS was most highly expressed in meristematic block tissue followed by embryogenic callus. Relatively lower expression was observed in cell suspension culture and watery callus for SERK, LEC2 and WUS and in in vitro leaf for BBM. For gene specific methylation determined by bisulfite sequencing data, embryogenic callus samples had the lowest levels of DNA methylation at CG, CHG and CHH contexts of SERK, LEC2 and WUS. We observed negative correlation between DNA methylation at the CG and CHG contexts and the expression levels of SERK, BBM, LEC2 and WUS. Based on our results, we suggest that relatively higher expression and lower level of DNA methylation of SERK, BBM, LEC2 and WUS are associated with somatic embryogenesis and plant regeneration in B. rotunda.
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.
Antimelanogenesis and Anti-Inflammatory Activity of Selected Culinary-Medicinal Mushrooms

Saad HM, Sim KS, Tan YS

Int J Med Mushrooms, 2018;20(2):141-153.
PMID: 29773006 DOI: 10.1615/IntJMedMushrooms.2018025463

Five culinary-medicinal mushrooms are commonly available in the Malaysian market: Agaricus bisporus (white and brown), Ganoderma lucidum, Hypsizygus marmoreus, Pleurotus floridanus, and P. pulmonarius. These species were selected for use in the current study, the aim of which was to investigate the antimelanogenesis and anti-inflammatory activity of these mushrooms in an attempt to evaluate their potential use in cosmeceuticals. Mushroom fruiting bodies were extracted with hot water, and the extracts were freeze-dried before testing. The antimelanogenesis activity of the extracts was determined by cell viability assay, measurement of intracellular melanin content, and cellular tyrosinase assay with B16F10 melanoma cells. The anti-inflammatory activity of the mushroom extracts was tested by measuring the levels of nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin-10 excreted by RAW264.7 macrophages. Brown A. bisporus reduced intracellular melanin content to the largest extent-up to 57.05 ± 3.90%-without a cytotoxic effect on B16F10 melanoma cells. This extract also reduced cellular tyrosinase activity to 17.93 ± 2.65%, performing better than kojic acid, the positive control. In parallel, the extract from brown A. bisporus, at the highest concentration tested, has appreciable anti-inflammatory activity through reductions of NO and TNF-α levels. The other 5 extracts showed moderate antimelanogenesis and anti-inflammatory activities. In summary, our findings show that A. bisporus (brown) extract has the potential to be used as an ingredient in whitening skincare products and to sooth the inflammatory response on the skin.
Fulltext Crystal structure of (4,4'-bipyridyl-κN)bis-[N-(2-hydroxy-ethyl)-N-iso-propyl-dithio-carbamato-κ2S,S']zinc(II)-4,4'-bipyridyl (2/1) and its isostructural cadmium(II) analogue

Tan YS, Tiekink ERT

Acta Crystallogr E Crystallogr Commun, 2017 Nov 01;73(Pt 11):1642-1646.
PMID: 29152341 DOI: 10.1107/S2056989017014396

The title structures, [M(C6H12NOS2)2(C10H8N2)]·0.5C10H8N2, for M = Zn, (I), and Cd, (II), feature terminally bound 4,4'-bipyridyl ligands and non-coordinating 4,4'-bi-pyridyl mol-ecules, with the latter disposed about a centre of inversion. The coordination geometry about the metal atom is defined by two non-symmetrically chelating di-thio-carbamate ligands and a pyridyl N atom. The NS4 donor sets are distorted but, approximate to trigonal bipyramidal in each case. In the crystal, hy-droxy-O-H⋯O(hy-droxy) and hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds between the zinc-containing mol-ecules lead to a supra-molecular layer parallel to (100). The three-dimensional architecture arises as the layers are linked via methine-C-H⋯S, pyridyl-C-H⋯O(hy-droxy) and π-π [inter-centroid distance between coordinated pyridyl rings = 3.6246 (18) Å] inter-actions. Channels along the c-axis direction are occupied by the non-coordinating 4,4'-bipyridine mol-ecules, which are held in place by C-H⋯π(chelate ring) contacts.
Fulltext Escaping introns in COI through cDNA barcoding of mushrooms: Pleurotus as a test case

Avin FA, Subha B, Tan YS, Braukmann TWA, Vikineswary S, Hebert PDN

Ecol Evol, 2017 09;7(17):6972-6980.
PMID: 28904776 DOI: 10.1002/ece3.3049

DNA barcoding involves the use of one or more short, standardized DNA fragments for the rapid identification of species. A 648-bp segment near the 5' terminus of the mitochondrial cytochrome c oxidase subunit I (COI) gene has been adopted as the universal DNA barcode for members of the animal kingdom, but its utility in mushrooms is complicated by the frequent occurrence of large introns. As a consequence, ITS has been adopted as the standard DNA barcode marker for mushrooms despite several shortcomings. This study employed newly designed primers coupled with cDNA analysis to examine COI sequence diversity in six species of Pleurotus and compared these results with those for ITS. The ability of the COI gene to discriminate six species of Pleurotus, the commonly cultivated oyster mushroom, was examined by analysis of cDNA. The amplification success, sequence variation within and among species, and the ability to design effective primers was tested. We compared ITS sequences to their COI cDNA counterparts for all isolates. ITS discriminated between all six species, but some sequence results were uninterpretable, because of length variation among ITS copies. By comparison, a complete COI sequences were recovered from all but three individuals of Pleurotus giganteus where only the 5' region was obtained. The COI sequences permitted the resolution of all species when partial data was excluded for P. giganteus. Our results suggest that COI can be a useful barcode marker for mushrooms when cDNA analysis is adopted, permitting identifications in cases where ITS cannot be recovered or where it offers higher resolution when fresh tissue is. The suitability of this approach remains to be confirmed for other mushrooms.
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.

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