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Fulltext Effect of drying methods on yield, physicochemical properties, and total polyphenol content of chamomile extract powder

Lee SY, Ferdinand V, Siow LF

Front Pharmacol, 2022;13:1003209.
PMID: 36408266 DOI: 10.3389/fphar.2022.1003209

Chamomile (Matricaria chamomilla L.) is a traditional medicinal plant used to treat hay fever, inflammation, muscle spasms, menstrual disorders, insomnia ulcers, wounds, gastrointestinal disorders, rheumatic pain, and hemorrhoids. Dried chamomile flowers have a longer shelf life and the dried extract in form of powder offers much flexibility for new therapeutic formulations as it could be used as a replacement for liquid extract and serve as a shelf-stable ingredient in new applications. This study aims to determine the effect of drying methods, i.e., convection oven-drying at 45 °C, freeze-drying at -50°C, and spray-drying at 140°C at 10.5 and 12 ml/min, respectively) on powder yield, physicochemical properties (moisture content, water activity, and color attributes), and total polyphenol content of chamomile extract powder. Our findings showed that spray-drying conducted at 140°C, 12 ml/min resulted in the lowest yield of powder (16.67%) compared to convection oven-drying (90.17%) and freeze-drying (83.24%). Decreasing the feed flow rate to 10.5 ml/min during spraying caused an increase in powder yield to 26.99%. The moisture content of spray-dried chamomile extract powder obtained at 140°C, 10.5 ml/min was higher (11.00%) compared to that of convection oven-dried (8.50%) and freeze-dried (7.50%). Both convection oven-dried and freeze-dried chamomile extract powder displayed no significant difference (p > 0.05) in moisture content. The higher feed flow rate (12 ml/min) in spray-drying also led to an increase in the moisture content of chamomile extract powder to 12.00%. The higher residual moisture found in the spray-dried samples resulted in partial agglomeration of particles. In terms of water activity, freeze-dried chamomile extract powder was found to have the highest water activity (0.63) compared to that of convection oven-dried (0.52), spray-dried at 140°C, 10.5 ml/min (0.57), and spray-dried at 140°C, 12 ml/min (0.58). Spray-dried and freeze-dried chamomile extract powder with high moisture content and water activity could be highly susceptible to microbial growth. In terms of color attributes, higher drying temperature in spray-drying led to darker, redder, and more yellowish chamomile extract powder that could be caused by heat-induced Maillard reaction and caramelization. Since lower drying temperature was used in both convection oven-drying and freeze-drying, both convection oven-dried (56.94 mg GAE/g powder) and freeze-dried chamomile extract powder (55.98 mg GAE/g powder) were found to have higher total polyphenol content compared to those of spray-dried (42.79-46.79 mg GAE/g powder). The present findings allow us to understand the effect of drying methods on the properties of chamomile extract powder and provide a better drying option to dry chamomile extract. Due to higher powder yield with ideal powder properties such as low moisture content and water activity, desirable color, and high total polyphenol content obtained from convection oven-drying, convection oven-drying was a better option than freeze-drying and spray-drying for drying chamomile extract.
Egg white lysozyme purification by a stirred cell contactor equipped with a weak ion-exchange nanofiber membrane: Process development and scale-up

Lee SY, Liu BL, Wu JY, Chang YK

Food Chem, 2021 Feb 15;338:128144.
PMID: 33092004 DOI: 10.1016/j.foodchem.2020.128144

A weak ion-exchange membrane (P-COOH) was synthesized by alkaline hydrolysis of a polyacrylonitrile nanofiber membrane prepared by electrospinning process. The P-COOH membrane was characterized for its physical properties and its application for purification of lysozyme from chicken egg white was investigated. The lysozyme adsorption efficiency of the P-COOH membrane operating in a stirred cell contactor (Millipore, Model 8010) was evaluated. The effects of key parameters such as the feed concentration, the rotating speed, the flow rate of feed and the operating pressure were studied. The results showed successful purification of lysozyme with a high recovery yield of 98% and a purification factor of 63 in a single step. The purification strategy was scaled-up to the higher feedstock loading volume of 32.7 and 70 mL using stirred cell contactors of Model 8050 and 8200, respectively. The scale-up processes achieved similar purification results, proving linear scalability of the purification technique adopted.
Electrochemical genosensor assay using lyophilized gold nanoparticles/latex microsphere label for detection of Vibrio cholerae

Liew PS, Lertanantawong B, Lee SY, Manickam R, Lee YH, Surareungchai W

Talanta, 2015 Jul 1;139:167-73.
PMID: 25882423 DOI: 10.1016/j.talanta.2015.02.054

Vibrio cholerae is a Gram-negative bacterium that causes cholera, a diarrheal disease. Cholera is widespread in poor, under-developed or disaster-hit countries that have poor water sanitation. Hence, a rapid detection method for V. cholerae in the field under these resource-limited settings is required. In this paper, we describe the development of an electrochemical genosensor assay using lyophilized gold nanoparticles/latex microsphere (AuNPs-PSA) reporter label. The reporter label mixture was prepared by lyophilization of AuNPs-PSA-avidin conjugate with different types of stabilizers. The best stabilizer was 5% sorbitol, which was able to preserve the dried conjugate for up to 30 days. Three methods of DNA hybridization were compared and the one-step sandwich hybridization method was chosen as it was fastest and highly specific. The performance of the assay using the lyophilized reagents was comparable to the wet form for detection of 1aM to 1fM of linear target DNA. The assay was highly specific for V. cholerae, with a detection limit of 1fM of PCR products. The ability of the sensor is to detect LAMP products as low as 50ngµl(-1). The novel lyophilized AuNPs-PSA-avidin reporter label with electrochemical genosensor detection could facilitate the rapid on-site detection of V. cholerae.
Evaluating new bio-hydrogen producers: Clostridium perfringens strain JJC, Clostridium bifermentans strain WYM and Clostridium sp. strain Ade.TY

Wong YM, Wu TY, Ling TC, Show PL, Lee SY, Chang JS, et al.

J Biosci Bioeng, 2018 May;125(5):590-598.
PMID: 29352712 DOI: 10.1016/j.jbiosc.2017.12.012

Three newly discovered H2 producing bacteria namely Clostridium perfringens strain JJC, Clostridium bifermentans strain WYM and Clostridium sp. strain Ade.TY originated from landfill leachate sludge have demonstrated highly efficient H2 production. The maximum H2 production attained from these isolates are in the descending order of strain C. perfringens strain JJC > C. bifermentans strain WYM > Clostridium sp. strain Ade.TY with yield of 4.68 ± 0.12, 3.29 ± 0.11, and 2.87 ± 0.10 mol H2/mol glucose, respectively. The result has broken the conventional theoretical yield of 4 mol H2/mol glucose. These isolates were thermodynamically favourable with Gibbs free energy between -33 and -35 kJ/mol (under process conditions: pH 6, 37 °C and 5 g/L glucose). All three isolates favour butyrate pathway for H2 production with the ratio of acetate and butyrate of 0.77, 0.65 and 0.80 for strain JJC, WYM and Ade.TY, respectively. This study reported provides a new insight on the potential of unique bacteria in H2 production.
Fulltext Evaluation of BRCA1 and BRCA2 mutations and risk-prediction models in a typical Asian country (Malaysia) with a relatively low incidence of breast cancer

Thirthagiri E, Lee SY, Kang P, Lee DS, Toh GT, Selamat S, et al.

Breast Cancer Res, 2008;10(4):R59.
PMID: 18627636 DOI: 10.1186/bcr2118

The cost of genetic testing and the limited knowledge about the BRCA1 and BRCA2 genes in different ethnic groups has limited its availability in medium- and low-resource countries, including Malaysia. In addition, the applicability of many risk-assessment tools, such as the Manchester Scoring System and BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm) which were developed based on mutation rates observed primarily in Caucasian populations using data from multiplex families, and in populations where the rate of breast cancer is higher, has not been widely tested in Asia or in Asians living elsewhere. Here, we report the results of genetic testing for mutations in the BRCA1 or BRCA2 genes in a series of families with breast cancer in the multi-ethnic population (Malay, Chinese and Indian) of Malaysia.
Fulltext Expert appraisal of criteria for assessing gaming disorder: an international Delphi study

Castro-Calvo J, King DL, Stein DJ, Brand M, Carmi L, Chamberlain SR, et al.

Addiction, 2021 09;116(9):2463-2475.
PMID: 33449441 DOI: 10.1111/add.15411

BACKGROUND AND AIMS: Following the recognition of 'internet gaming disorder' (IGD) as a condition requiring further study by the DSM-5, 'gaming disorder' (GD) was officially included as a diagnostic entity by the World Health Organization (WHO) in the 11th revision of the International Classification of Diseases (ICD-11). However, the proposed diagnostic criteria for gaming disorder remain the subject of debate, and there has been no systematic attempt to integrate the views of different groups of experts. To achieve a more systematic agreement on this new disorder, this study employed the Delphi expert consensus method to obtain expert agreement on the diagnostic validity, clinical utility and prognostic value of the DSM-5 criteria and ICD-11 clinical guidelines for GD.
METHODS: A total of 29 international experts with clinical and/or research experience in GD completed three iterative rounds of a Delphi survey. Experts rated proposed criteria in progressive rounds until a pre-determined level of agreement was achieved.
RESULTS: For DSM-5 IGD criteria, there was an agreement both that a subset had high diagnostic validity, clinical utility and prognostic value and that some (e.g. tolerance, deception) had low diagnostic validity, clinical utility and prognostic value. Crucially, some DSM-5 criteria (e.g. escapism/mood regulation, tolerance) were regarded as incapable of distinguishing between problematic and non-problematic gaming. In contrast, ICD-11 diagnostic guidelines for GD (except for the criterion relating to diminished non-gaming interests) were judged as presenting high diagnostic validity, clinical utility and prognostic value.
CONCLUSIONS: This Delphi survey provides a foundation for identifying the most diagnostically valid and clinically useful criteria for GD. There was expert agreement that some DSM-5 criteria were not clinically relevant and may pathologize non-problematic patterns of gaming, whereas ICD-11 diagnostic guidelines are likely to diagnose GD adequately and avoid pathologizing.
Flavonoids and phenolic acids from Labisia pumila (Kacip Fatimah)

Chua LS, Latiff NA, Lee SY, Lee CT, Sarmidi MR, Aziz RA

Food Chem, 2011 Aug 1;127(3):1186-92.
PMID: 25214112 DOI: 10.1016/j.foodchem.2011.01.122

Both total phenolic content (TPC) and total flavonoid content (TFC) of Labisia pumila extracts were determined spectrophotometrically. L. pumila leaves extracted in 60% methanol (MeOH) were fractionated on C18 cartridge and the antioxidant property of each fraction was determined by measuring free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity. The 40% MeOH fraction exhibited the highest scavenging activity. Nine flavonols (quercetin, myricetin and kaempferol), two flavanols (catechin and epigallocatechin) and nine phenolic acids were identified from this active fraction by UPLC-ESI-MS/MS, and confirmed by comparison with the mass spectra of standard aglycones, theoretical fragments generated from MS Fragmenter software, and literature values.
Genetic and immunologic relationships between vaccine and field strains for vaccine selection of type A foot-and-mouth disease virus circulating in East Asia

Lee SY, Park ME, Kim RH, Ko MK, Lee KN, Kim SM, et al.

Vaccine, 2015 Jan 29;33(5):664-9.
PMID: 25528521 DOI: 10.1016/j.vaccine.2014.12.007

Of the seven known serotypes of foot-and-mouth disease virus (FMDV), type A has the most diverse variations. Genetic variations also occur frequently at VP1, VP2, VP3, and VP4 because these proteins constitute the viral capsid. The structural proteins of FMDV, which are closely related to immunologic correlations, are the most easily analyzed because they have highly accessible information. In this study we analyzed the type A vaccine viruses by alignment of available sequences in order to find appropriate vaccine strains. The matching rate of ASIA topotype-specific sites (20 amino acids) located on the viral surface, which are mainly VP1 and VP2, was highly related to immunologic reactivity. Among the available vaccines analyzed in this study, we suggest that A Malaysia 97 could be used as a vaccine virus as it has the highest genetic similarity and immunologic aspects to field strains originating in East Asia.
Fulltext Genome Size, Molecular Phylogeny, and Evolutionary History of the Tribe Aquilarieae (Thymelaeaceae), the Natural Source of Agarwood

Farah AH, Lee SY, Gao Z, Yao TL, Madon M, Mohamed R

Front Plant Sci, 2018;9:712.
PMID: 29896211 DOI: 10.3389/fpls.2018.00712

The tribe Aquilarieae of the family Thymelaeaceae consists of two genera, Aquilaria and Gyrinops, with a total of 30 species, distributed from northeast India, through southeast Asia and the south of China, to Papua New Guinea. They are an important botanical resource for fragrant agarwood, a prized product derived from injured or infected stems of these species. The aim of this study was to estimate the genome size of selected Aquilaria species and comprehend the evolutionary history of Aquilarieae speciation through molecular phylogeny. Five non-coding chloroplast DNA regions and a nuclear region were sequenced from 12 Aquilaria and three Gyrinops species. Phylogenetic trees constructed using combined chloroplast DNA sequences revealed relationships of the studied 15 members in Aquilarieae, while nuclear ribosomal DNA internal transcribed spacer (ITS) sequences showed a paraphyletic relationship between Aquilaria species from Indochina and Malesian. We exposed, for the first time, the estimated divergence time for Aquilarieae speciation, which was speculated to happen during the Miocene Epoch. The ancestral split and biogeographic pattern of studied species were discussed. Results showed no large variation in the 2C-values for the five Aquilaria species (1.35-2.23 pg). Further investigation into the genome size may provide additional information regarding ancestral traits and its evolution history.
Fulltext Getting patient blood management Pillar 1 right in the Asia-Pacific: a call for action

Abdullah HR, Ang AL, Froessler B, Hofmann A, Jang JH, Kim YW, et al.

Singapore Med J, 2020 Jun;61(6):287-296.
PMID: 31044255 DOI: 10.11622/smedj.2019037

Preoperative anaemia is common in the Asia-Pacific. Iron deficiency anaemia (IDA) is a risk factor that can be addressed under patient blood management (PBM) Pillar 1, leading to reduced morbidity and mortality. We examined PBM implementation under four different healthcare systems, identified challenges and proposed several measures: (a) Test for anaemia once patients are scheduled for surgery. (b) Inform patients about risks of preoperative anaemia and benefits of treatment. (c) Treat IDA and replenish iron stores before surgery, using intravenous iron when oral treatment is ineffective, not tolerated or when rapid iron replenishment is needed; transfusion should not be the default management. (d) Harness support from multiple medical disciplines and relevant bodies to promote PBM implementation. (e) Demonstrate better outcomes and cost savings from reduced mortality and morbidity. Although PBM implementation may seem complex and daunting, it is feasible to start small. Implementing PBM Pillar 1, particularly in preoperative patients, is a sensible first step regardless of the healthcare setting.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.

Autophagy, 2016;12(1):1-222.
PMID: 26799652 DOI: 10.1080/15548627.2015.1100356
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1

Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.

Autophagy, 2021 Jan;17(1):1-382.
PMID: 33634751 DOI: 10.1080/15548627.2020.1797280

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
Highly divergent regions in the complete plastome sequences of Aquilaria are suitable for DNA barcoding applications including identifying species origin of agarwood products

Hishamuddin MS, Lee SY, Syazwan SA, Ramlee SI, Lamasudin DU, Mohamed R

3 Biotech, 2023 Mar;13(3):78.
PMID: 36761338 DOI: 10.1007/s13205-023-03479-1

Members of Aquilaria Lam. (Thymelaeaceae) are evergreen trees that are widely distributed in the Indomalesia region. Aquilaria is highly prized for its unique scented resin, agarwood, which is often the subject of unlawful trade activities. Survival of the tree is heavily threatened by destructive harvesting and agarwood poaching, leading to its protection under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Unfortunately, an efficient species identification method, which is crucial to aid in the conservation efforts of Aquilaria is lacking. Here, we described our search for a suitable specific DNA barcode for Aquilaria species using eight complete plastome sequences. We identified five highly variable regions (HVR) (matK-rps16, ndhF-rpl32, psbJ-petA, trnD, and trnT-trnL) in the plastomes. These regions were further analyzed using the neighbor-joining (NJ) method to assess their ability at discriminating the eight species. Coupled with in silico primer design, two potential barcoding regions, psbJ-petA and trnT-trnL, were identified. Their strengths in species delimitation were evaluated individually and in combination, via DNA barcoding analysis. Our findings showed that the combined dataset, psbJ-petA + trnT-trnL, effectively resolved members of the genus Aquilaria by clustering all species into their respective clades. In addition, we demonstrated that the newly proposed DNA barcode was capable at identifying the species of origin of six commercial agarwood samples that were included as unknown samples. Such achievement offers a new technical advancement, useful in the combat against illicit agarwood trades and in assisting the conservation of these valuable species in natural populations.
SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-023-03479-1.
Identification of germline alterations in breast cancer predisposition genes among Malaysian breast cancer patients using panel testing

Ng PS, Wen WX, Fadlullah MZ, Yoon SY, Lee SY, Thong MK, et al.

Clin Genet, 2016 10;90(4):315-23.
PMID: 26757417 DOI: 10.1111/cge.12735

Although an association between protein-truncating variants and breast cancer risk has been established for 11 genes, only alterations in BRCA1, BRCA2, TP53 and PALB2 have been reported in Asian populations. Given that the age of onset of breast cancer is lower in Asians, it is estimated that inherited predisposition to breast cancer may be more significant. To determine the potential utility of panel testing, we investigated the prevalence of germline alterations in 11 established and 4 likely breast cancer genes in a cross-sectional hospital-based cohort of 108 moderate to high-risk breast cancer patients using targeted next generation sequencing. Twenty patients (19%) were identified to carry deleterious mutations, of whom 13 (12%) were in the BRCA1 or BRCA2, 6 (6%) were in five other known breast cancer predisposition genes and 1 patient had a mutation in both BRCA2 and BARD1. Our study shows that BRCA1 and BRCA2 account for the majority of genetic predisposition to breast cancer in our cohort of Asian women. Although mutations in other known breast cancer genes are found, the functional significance and breast cancer risk have not yet been determined, thus limiting the clinical utility of panel testing in Asian populations.
Impact of BRCA1/2 cascade testing on anxiety, depression, and cancer worry levels among unaffected relatives in a multiethnic Asian cohort

Padmanabhan H, Mariapun S, Lee SY, Hassan NT, Lee DS, Meiser B, et al.

J Genet Couns, 2023 Feb;32(1):43-56.
PMID: 35913122 DOI: 10.1002/jgc4.1619

Cascade testing for families with BRCA pathogenic variants is important to identify relatives who are carriers. These relatives can benefit from appropriate risk management and preventative strategies arising from an inherited increased risk of breast, ovarian, prostate, melanoma, and pancreatic cancers. Cascade testing has the potential to enable cost-effective cancer control even in low- and middle-income settings, but few studies have hitherto evaluated the psychosocial impact of cascade testing in an Asian population, where the cultural and religious beliefs around inheritance and destiny have previously been shown to influence perception and attitudes toward screening. In this study, we evaluated the short- and long-term psychosocial impact of genetic testing among unaffected relatives of probands identified through the Malaysian Breast Cancer Genetics Study and the Malaysian Ovarian Cancer Study, using validated questionnaires (Hospital Anxiety and Depression Scale and Cancer Worry Scale) administered at baseline, and 1-month and 2-year post-disclosure of results. Of the 305 unaffected relatives from 98 independent families who were offered cascade testing, 256 (84%) completed predictive testing and family history of cancers was the only factor significantly associated with uptake of predictive testing. We found that the levels of anxiety, depression, and cancer worry among unaffected relatives decreased significantly after result disclosure and remained low 2-year post-result disclosure. Younger relatives and relatives of Malay descent had higher cancer worry at both baseline and after result disclosure compared to those of Chinese and Indian descent, whereas relatives of Indian descent and those with family history of cancers had higher anxiety and depression levels post-result disclosure. Taken together, the results from this Asian cohort highlight the differences in psychosocial needs in different communities and inform the development of culture-specific genetic counseling strategies.
Impact of Double Expression of C-MYC/BCL2 Protein and Cell of Origin Subtypes on the Outcome among Patients with Diffuse Large B-Cell Lymphoma: a Single Asian Center Experience

Teoh CS, Lee SY, Chiang SK, Chew TK, Goh AS

Asian Pac J Cancer Prev, 2018 May 26;19(5):1229-1236.
PMID: 29801406

Background: Diffuse large B-cell lymphoma (DLBCL) with double expression of c-MYC and BCL2 protein is
associated with dismal outcome after treatment with R-CHOP. Local data on disease burden and survival outcome in
DLBCL is limited. We investigated the prognostic values of c-MYC/BCL2 protein co-expression and cell of origin
subtypes using immunohistochemistry (IHC) and to determine their associations with multiethnic groups under
resource limited setting. Methods: This was a retrospective study which recruited 104 patients in between June 2012
and December 2015 for IHC review and analysis. Result: We demonstrated that patients with high International
Prognostic Index (IPI) (score 3-5) and co-expression of c-MYC/BCL2 protein had significant inferior overall survival
(OS) and event free survival (EFS) respectively (P<0.05). c-MYC/BCL2 protein co-expression was more common in
non-germinal center B-cell (non-GCB) (P=0.048) and contributed to adverse prognosis in this group of patients (OS,
P=0.004; EFS, P=0.005). In multivariate analysis, double-protein co-expression was a significant independent predictor
of inferior outcome after adjusted for IPI and cell of origin subtypes (OS hazard ratio [HR], 2.11; 95% CI, 1.01 to 4.04;
P=0.048; EFS HR, 2.31; 95% CI, 1.05 to 5.04; P=0.036). In addition, non-GCB subtype was more common than GCB
in Malays (60% vs 40%, P=0.106) and Chinese (81.2% vs 18.8%, P=0.042). Indians had more DLBCL without c-MYC/
BCL2 protein co-expression compared to double-protein positive cases (66.7% vs 33.3%, P=0.414). Otherwise, the
prognostic impact of ethnicity on survival outcome was insignificant (P=0.961). Conclusion: c-MYC/BCL2 protein
co-expression in non-GCB subtype constituted a unique group with extremely inferior outcome regardless of ethnicity.
Gene expression profile (GEP) may possibly provide insights into the cause of discrepancies in DLBCL subtypes and
protein expression among the multiethnic groups.
Fulltext In Vitro Wound Healing Potential of Flavonoid C-Glycosides from Oil Palm (Elaeis guineensis Jacq.) Leaves on 3T3 Fibroblast Cells

Che Zain MS, Lee SY, Sarian MN, Fakurazi S, Shaari K

Antioxidants (Basel), 2020 Apr 17;9(4).
PMID: 32316665 DOI: 10.3390/antiox9040326

Oil palm (Elaeis guineensis Jacq.) leaves (OPL) are widely available at zero cost in Southeast Asia countries, especially in Malaysia and Indonesia due to large scale oil palm plantations. OPLs contain a large amount of flavonoids in particular flavonoid C-glycosides, which are known to possess useful biological properties including antioxidant and wound healing properties. The present study aimed at evaluating the wound healing efficacy of OPL in various solvent extracts and flavonoid enriched fractions and to determine the contribution of flavonoid C-glycosides (orientin, isoorientin, vitexin and isovitexin) using in-vitro scratch assay on 3T3 fibroblast cells. Solvent crude extracts with different polarity were screened and the most active extract was subjected to acid hydrolysis. The crude and acid hydrolysed extracts were further enriched using macroporous resins, XAD7HP. UHPLC-UV/PDA and LC-MS/MS analysis were applied for identification and confirmation of flavonoid C-glycosides. The wound healing properties comprised of cell viability, cell proliferation and cell migration were studied. Allantoin was used as a positive control to compare the efficacy among the tested samples. The results revealed all OPL crude extracts, flavonoid enriched fractions and flavonoid C-glycosides were non-toxic at concentrations below 25 µg/mL and showed better cell proliferation and migration activities at low concentrations than higher concentrations.. This study also demonstrated orientin, isoorientin, vitexin and isovitexin presented in OPL extracts and flavonoid enriched fractions stimulated proliferation and migration of 3T3 fibroblast cells. Hence, these findings may pose potential therapeutic bioactive agents for wound healing by enhancing fibroblast proliferation and migration.
In vitro gastrointestinal digestion and fecal fermentation reveal the effect of different encapsulation materials on the release, degradation and modulation of gut microbiota of blueberry anthocyanin extract

Wu Y, Han Y, Tao Y, Li D, Xie G, Show PL, et al.

Food Res Int, 2020 06;132:109098.
PMID: 32331662 DOI: 10.1016/j.foodres.2020.109098

In this study, four different selected wall materials (namely gelatin, soy protein isolate, maltodextrin and Arabic gum) were applied for blueberry anthocyanin extract encapsulation. The effect of these wall material types on the release and degradation of anthocyanin and the modulation of gut microbiota during in vitro simulated gastrointestinal digestion and colonic fermentation were investigated. It was found that the encapsulation of anthocyanin extract using appropriate wall material could significantly enhance the colonic accessibility of anthocyanins. Soy protein isolate and gelatin delayed the release of anthocyanins, whereas the other two wall materials displayed no significant effect on the release time of anthocyanins. Gut microbiota mainly metabolized some phenolic compounds such as 4-hydroxycinnamic acid and chlorogenic acid. Meanwhile, different fermented anthocyanin extract microcapsule broth could significantly decrease the composition and abundance of Firmicutes and increase that of Bacteroidetes. Furthermore, the presence of anthocyanin extract microcapsules, especially those encapsulated with soy protein isolate, promoted the biosynthesis of short-chain fatty acids by gut microbiota. It is concluded that, amongst the wall materials studied, soy protein isolate appeared to be a functional and suitable candidate to delay anthocyanin release and prevent disease through the promotion of gut health.
Fulltext Inherited mutations in BRCA1 and BRCA2 in an unselected multiethnic cohort of Asian patients with breast cancer and healthy controls from Malaysia

Wen WX, Allen J, Lai KN, Mariapun S, Hasan SN, Ng PS, et al.

J Med Genet, 2018 02;55(2):97-103.
PMID: 28993434 DOI: 10.1136/jmedgenet-2017-104947

BACKGROUND: Genetic testing for BRCA1 and BRCA2 is offered typically to selected women based on age of onset and family history of cancer. However, current internationally accepted genetic testing referral guidelines are built mostly on data from cancer genetics clinics in women of European descent. To evaluate the appropriateness of such guidelines in Asians, we have determined the prevalence of germ line variants in an unselected cohort of Asian patients with breast cancer and healthy controls.
METHODS: Germ line DNA from a hospital-based study of 2575 unselected patients with breast cancer and 2809 healthy controls were subjected to amplicon-based targeted sequencing of exonic and proximal splice site junction regions of BRCA1 and BRCA2 using the Fluidigm Access Array system, with sequencing conducted on a Illumina HiSeq2500 platform. Variant calling was performed with GATK UnifiedGenotyper and were validated by Sanger sequencing.
RESULTS: Fifty-five (2.1%) BRCA1 and 66 (2.6%) BRCA2 deleterious mutations were identified among patients with breast cancer and five (0.18%) BRCA1 and six (0.21%) BRCA2 mutations among controls. One thousand one hundred and eighty-six (46%) patients and 97 (80%) carriers fulfilled the National Comprehensive Cancer Network guidelines for genetic testing.
CONCLUSION: Five per cent of unselected Asian patients with breast cancer carry deleterious variants in BRCA1 or BRCA2. While current referral guidelines identified the majority of carriers, one in two patients would be referred for genetic services. Given that such services are largely unavailable in majority of low-resource settings in Asia, our study highlights the need for more efficient guidelines to identify at-risk individuals in Asia.
Integration of Choline Chloride-Based Natural Deep Eutectic Solvents and Macroporous Resin for Green Production of Enriched Oil Palm Flavonoids as Natural Wound Healing Agents

Che Zain MS, Yeoh JX, Lee SY, Afzan A, Shaari K

Antioxidants (Basel), 2021 Nov 12;10(11).
PMID: 34829674 DOI: 10.3390/antiox10111802

Huge quantities of oil palm (Elaeis guineensis Jacq.) leaves (OPL) are generated as agricultural biomass from oil palm plantations. OPL are known to contain significant amounts of flavonoids. For maximal exploitation of these valuable antioxidant compounds, an innovative and sustainable extraction method employing natural deep eutectic solvents (NaDES) combined with ultrasonic assisted extraction was developed. Various NaDES composed of choline chloride as the hydrogen bond donor (HBD) and 1,2 propanediol (PD), 1,4 butanediol (BD), glycerol (GLY), glucose (GLU), maltose (MAL), and lactic acid (LA) as the hydrogen bond acceptor (HBA) were synthesized. The influence of these compositions, the methods of their synthesis, molar ratios, and water contents on their capacity to extract flavonoids from OPL was evaluated. Based on the results, it was found that methods which incorporate a heating step produced NaDES with the best capacity to extract OPL flavonoids. These thermal methods combined with molar ratios of 1:3 or 1:4 and water contents of 17 to 50% were found to be the optimal conditions for preparing NaDES, specifically when applied to the PD, BD, and GLY NaDES. Subsequently, UHPLC-UV/PDA-MS/MS analysis revealed NaDES extracts recovered by macroporous adsorption resin XAD7HP were able to optimally extract at least twelve luteolin and apigenin derivatives in OPL NaDES extracts prepared from glycerol and 1,4-butanediol demonstrated better and comparable efficiency as aqueous methanol in extracting flavonoids from OPL. The in vitro studies of antioxidant and wound healing properties supported these findings by exhibiting good free radical scavenging, cell proliferation, and migration activities. Additionally, the NaDES extracts also showed non-cytotoxicity effects at 1000 µg/mL and below on 3T3 fibroblast cells. Results of the study showed that NaDES could be a promising eco-friendly green solvent to extract bioactive OPL flavonoids that have great potential for applications as wound healing agents.

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