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  1. James SL, Castle CD, Dingels ZV, Fox JT, Hamilton EB, Liu Z, et al.
    Inj Prev, 2020 10;26(Supp 1):i96-i114.
    PMID: 32332142 DOI: 10.1136/injuryprev-2019-043494
    BACKGROUND: Past research in population health trends has shown that injuries form a substantial burden of population health loss. Regular updates to injury burden assessments are critical. We report Global Burden of Disease (GBD) 2017 Study estimates on morbidity and mortality for all injuries.

    METHODS: We reviewed results for injuries from the GBD 2017 study. GBD 2017 measured injury-specific mortality and years of life lost (YLLs) using the Cause of Death Ensemble model. To measure non-fatal injuries, GBD 2017 modelled injury-specific incidence and converted this to prevalence and years lived with disability (YLDs). YLLs and YLDs were summed to calculate disability-adjusted life years (DALYs).

    FINDINGS: In 1990, there were 4 260 493 (4 085 700 to 4 396 138) injury deaths, which increased to 4 484 722 (4 332 010 to 4 585 554) deaths in 2017, while age-standardised mortality decreased from 1079 (1073 to 1086) to 738 (730 to 745) per 100 000. In 1990, there were 354 064 302 (95% uncertainty interval: 338 174 876 to 371 610 802) new cases of injury globally, which increased to 520 710 288 (493 430 247 to 547 988 635) new cases in 2017. During this time, age-standardised incidence decreased non-significantly from 6824 (6534 to 7147) to 6763 (6412 to 7118) per 100 000. Between 1990 and 2017, age-standardised DALYs decreased from 4947 (4655 to 5233) per 100 000 to 3267 (3058 to 3505).

    INTERPRETATION: Injuries are an important cause of health loss globally, though mortality has declined between 1990 and 2017. Future research in injury burden should focus on prevention in high-burden populations, improving data collection and ensuring access to medical care.

  2. James SL, Castle CD, Dingels ZV, Fox JT, Hamilton EB, Liu Z, et al.
    Inj Prev, 2020 Oct;26(Supp 1):i125-i153.
    PMID: 32839249 DOI: 10.1136/injuryprev-2019-043531
    BACKGROUND: While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria.

    METHODS: In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced.

    RESULTS: GBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes.

    CONCLUSIONS: GBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future.

  3. Haagsma JA, James SL, Castle CD, Dingels ZV, Fox JT, Hamilton EB, et al.
    Inj Prev, 2020 Oct;26(Supp 1):i12-i26.
    PMID: 31915273 DOI: 10.1136/injuryprev-2019-043296
    BACKGROUND: The epidemiological transition of non-communicable diseases replacing infectious diseases as the main contributors to disease burden has been well documented in global health literature. Less focus, however, has been given to the relationship between sociodemographic changes and injury. The aim of this study was to examine the association between disability-adjusted life years (DALYs) from injury for 195 countries and territories at different levels along the development spectrum between 1990 and 2017 based on the Global Burden of Disease (GBD) 2017 estimates.

    METHODS: Injury mortality was estimated using the GBD mortality database, corrections for garbage coding and CODEm-the cause of death ensemble modelling tool. Morbidity estimation was based on surveys and inpatient and outpatient data sets for 30 cause-of-injury with 47 nature-of-injury categories each. The Socio-demographic Index (SDI) is a composite indicator that includes lagged income per capita, average educational attainment over age 15 years and total fertility rate.

    RESULTS: For many causes of injury, age-standardised DALY rates declined with increasing SDI, although road injury, interpersonal violence and self-harm did not follow this pattern. Particularly for self-harm opposing patterns were observed in regions with similar SDI levels. For road injuries, this effect was less pronounced.

    CONCLUSIONS: The overall global pattern is that of declining injury burden with increasing SDI. However, not all injuries follow this pattern, which suggests multiple underlying mechanisms influencing injury DALYs. There is a need for a detailed understanding of these patterns to help to inform national and global efforts to address injury-related health outcomes across the development spectrum.

  4. Ashraf S, Ashraf S, Akmal R, Ashraf M, Kalsoom L, Maqsood A, et al.
    Trials, 2021 Sep 15;22(1):618.
    PMID: 34526081 DOI: 10.1186/s13063-021-05510-3
    OBJECTIVES: Considering the therapeutic potential of honey and Nigella sativa (HNS) in coronavirus disease 2019 (COVID-19) patients, the objective of the study is defined to evaluate the prophylactic role of HNS.

    TRIAL DESIGN: The study is a randomized, placebo-controlled, adaptive clinical trial with parallel group design, superiority framework with an allocation ratio of 1:1 among experimental (HNS) and placebo group. An interim analysis will be done when half of the patients have been recruited to evaluate the need to adapt sample size, efficacy, and futility of the trial.

    PARTICIPANTS: All asymptomatic patients with hospital or community based COVID-19 exposure will be screened if they have had 4 days exposure to a confirmed case. Non-pregnant adults with significant exposure level will be enrolled in the study High-risk exposure (<6 feet distance for >10min without face protection) Moderate exposure (<6 feet distance for >10min with face protection) Subjects with acute or chronic infection, COVID-19 vaccinated, and allergy to HNS will be excluded from the study. Recruitment will be done at Shaikh Zayed Post-Graduate Medical Institute, Ali Clinic and Doctors Lounge in Lahore (Pakistan).

    INTERVENTION AND COMPARATOR: In this clinical study, patients will receive either raw natural honey (0.5 g) and encapsulated organic Nigella sativa seeds (40 mg) per kg body weight per day or empty capsule with and 30 ml of 5% dextrose water as a placebo for 14 days. Both the natural products will be certified for standardization by Government College University (Botany department). Furthermore, each patient will be given standard care therapy according to version 3.0 of the COVID-19 clinical management guidelines by the Ministry of National Health Services of Pakistan.

    MAIN OUTCOMES: Primary outcome will be Incidence of COVID-19 cases within 14 days of randomisation. Secondary endpoints include incidence of COVID-19-related symptoms, hospitalizations, and deaths along with the severity of COVID-19-related symptoms till 14th day of randomization.

    RANDOMISATION: Participants will be randomized into experimental and control groups (1:1 allocation ratio) via the lottery method. There will be stratification based on high risk and moderate risk exposure.

    BLINDING (MASKING): Quadruple blinding will be ensured for the participants, care providers and outcome accessors. Data analysts will also be blinded to avoid conflict of interest. Site principal investigator will be responsible for ensuring masking.

    NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 1000 participants will be enrolled in the study with 1:1 allocation.

    TRIAL STATUS: The final protocol version 1.4 was approved by institutional review board of Shaikh Zayed Post-Graduate Medical Complex on February 15, 2021. The trial recruitment was started on March 05, 2021, with a trial completion date of February 15, 2022.

    TRIAL REGISTRATION: Clinical trial was registered on February 23, 2021, www.clinicaltrials.gov with registration ID NCT04767087 .

    FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). With the intention of expediting dissemination of this trial, the conventional formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines.

  5. Muhamad Rosli SH, Lau MS, Khalid T, Maarof SK, Jeyabalan S, Sirdar Ali S, et al.
    PMID: 36947708 DOI: 10.1080/19440049.2023.2183068
    3-Monochloropropane-1,2-diol esters (3-MCPDE) are food contaminants commonly found in refined vegetable oils and fats, which have possible carcinogenic implications in humans. To investigate this clinically, we conducted an occurrence level analysis on eight categories of retail and cooked food commonly consumed in Malaysia. This was used to estimate the daily exposure level, through a questionnaire-based case-control study involving 77 subjects with renal cancer, with 80 matching controls. Adjusted Odds Ratio (AOR) was calculated using the multiple logistic regression model adjusted for confounding factors. A pooled estimate of total 3-MCPDE intake per day was compared between both groups, to assess exposure and disease outcome. Among the food categories analysed, vegetable fats and oils recorded the highest occurrence levels (mean: 1.91 ± 1.90 mg/kg), significantly more than all other food categories (p 
  6. Eng-Chong T, Yean-Kee L, Chin-Fei C, Choon-Han H, Sher-Ming W, Li-Ping CT, et al.
    PMID: 23243448 DOI: 10.1155/2012/473637
    Boesenbergia rotunda is a herb from the Boesenbergia genera under the Zingiberaceae family. B. rotunda is widely found in Asian countries where it is commonly used as a food ingredient and in ethnomedicinal preparations. The popularity of its ethnomedicinal usage has drawn the attention of scientists worldwide to further investigate its medicinal properties. Advancement in drug design and discovery research has led to the development of synthetic drugs from B. rotunda metabolites via bioinformatics and medicinal chemistry studies. Furthermore, with the advent of genomics, transcriptomics, proteomics, and metabolomics, new insights on the biosynthetic pathways of B. rotunda metabolites can be elucidated, enabling researchers to predict the potential bioactive compounds responsible for the medicinal properties of the plant. The vast biological activities exhibited by the compounds obtained from B. rotunda warrant further investigation through studies such as drug discovery, polypharmacology, and drug delivery using nanotechnology.
  7. Md-Mustafa ND, Khalid N, Gao H, Peng Z, Alimin MF, Bujang N, et al.
    BMC Genomics, 2014;15:984.
    PMID: 25407215 DOI: 10.1186/1471-2164-15-984
    Panduratin A extracted from Boesenbergia rotunda is a flavonoid reported to possess a range of medicinal indications which include anti-dengue, anti-HIV, anti-cancer, antioxidant and anti-inflammatory properties. Boesenbergia rotunda is a plant from the Zingiberaceae family commonly used as a food ingredient and traditional medicine in Southeast Asia and China. Reports on the health benefits of secondary metabolites extracted from Boesenbergia rotunda over the last few years has resulted in rising demands for panduratin A. However large scale extraction has been hindered by the naturally low abundance of the compound and limited knowledge of its biosynthetic pathway.
  8. 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.
  9. Beh CY, Cheng EM, Mohd Nasir NF, Eng SK, Abdul Majid MS, Ridzuan MJM, et al.
    Int J Biol Macromol, 2021 Jan 01;166:1543-1553.
    PMID: 33181217 DOI: 10.1016/j.ijbiomac.2020.11.034
    This paper provides a comprehensive analysis of the dielectric and physicochemical properties of the porous hydroxyapatite/cornstarch (HAp/Cs) composites in a new perspective. The porous composites have been characterized via SEM, FTIR, XRD and dielectric spectroscopy. The dielectric permittivity spectra were obtained in Ku-band (12.4-18.0 GHz) and it was correlated with the physicochemical properties of the porous HAp/Cs. Porous HAp/Cs composites exhibits low ε' and negative ε″, which influenced by the microstructural morphology, interaction between Hap and Cs, as well as crystalline features due to the various proportion of the HAp/Cs. The physicochemical effect of the composites results in the dielectric polarization and energy loss. This phenomenon indicates the presence of the three obvious relaxation responses in the ε' spectrum (13.2-14.0, 15.2-16.0, and 16.6-17.4 GHz) and the negative behaviours in the ε″ spectrum. The relationships between physicochemical and dielectric properties of the porous composite facilitate the development of the non-destructive microwave evaluation test for the porous composite.
  10. Ng TL, Karim R, Tan YS, Teh HF, Danial AD, Ho LS, et al.
    PLoS One, 2016;11(6):e0156714.
    PMID: 27258536 DOI: 10.1371/journal.pone.0156714
    Interest in the medicinal properties of secondary metabolites of Boesenbergia rotunda (fingerroot ginger) has led to investigations into tissue culture of this plant. In this study, we profiled its primary and secondary metabolites, as well as hormones of embryogenic and non-embryogenic (dry and watery) callus and shoot base, Ultra Performance Liquid Chromatography-Mass Spectrometry together with histological characterization. Metabolite profiling showed relatively higher levels of glutamine, arginine and lysine in embryogenic callus than in dry and watery calli, while shoot base tissue showed an intermediate level of primary metabolites. For the five secondary metabolites analyzed (ie. panduratin, pinocembrin, pinostrobin, cardamonin and alpinetin), shoot base had the highest concentrations, followed by watery, dry and embryogenic calli. Furthermore, intracellular auxin levels were found to decrease from dry to watery calli, followed by shoot base and finally embryogenic calli. Our morphological observations showed the presence of fibrils on the cell surface of embryogenic callus while diphenylboric acid 2-aminoethylester staining indicated the presence of flavonoids in both dry and embryogenic calli. Periodic acid-Schiff staining showed that shoot base and dry and embryogenic calli contained starch reserves while none were found in watery callus. This study identified several primary metabolites that could be used as markers of embryogenic cells in B. rotunda, while secondary metabolite analysis indicated that biosynthesis pathways of these important metabolites may not be active in callus and embryogenic tissue.
  11. Afzan A, Lee JC, Adam Z, Mustafa Khalid N, Gunasegavan RDN, Md Noh MF, et al.
    Fitoterapia, 2024 Apr 09;175:105958.
    PMID: 38604262 DOI: 10.1016/j.fitote.2024.105958
    In our quest to discover advanced glycation end products (AGEs) inhibitors from Clinacanthus nutans (Burm.f.) Lindau leaves, we conducted a bioactivity-based molecular networking. This approach integrates LC-MS2 profiling and in vitro antiglycation data to predict bioactive compounds. We began by screening three extracts: 100% ethanol, 70% ethanol and 100% water alongside the in vitro antioxidant activity, total phenolics content (TPC) and schaftoside content. Among these extracts, 100% ethanol extract exhibited the highest total AGEs inhibition effects (IC50 = 80.18 ± 11.6 μg/mL), DPPH scavenging activity (IC50 = 747.40 ± 10.30 μg/mL) and TPC (26.54 ± 2.09 μg GAE /mg extract). Intriguingly, 100% ethanol extract contained the lowest amount of schaftoside, suggesting the involvement of other phytochemicals in the antiglycation effects. The molecular networking and in silico structural annotations of 401 LC-MS features detected in the fractions from 100% ethanol extract predicted 21 bioactive compounds (p  0.90), including several C40 carotenoids, alkaloids containing tetrapyrrole structures and fatty acids. On the contrary, all phenolics showed weak correlations with antiglycation effects. These predictions were further validated in vitro, where carotenoid lutein showed half maximal inhibitory concentration, IC50 = 96 ± 8 μM and selected flavonoid-C-glycosides exhibited weaker inhibitions (IC50 between 568 and 1922 μM). Notably, lutein content was higher in freeze-dried leaves (12.42 ± 0.82 mg/100 g) than oven-dried, although the former was associated with elevated mercury levels. In summary, C. nutans exhibited potential antiglycation and antioxidant activity, and lutein was identified as the main bioactive principle.
  12. Othman R, Kiat TS, Khalid N, Yusof R, Newhouse EI, Newhouse JS, et al.
    J Chem Inf Model, 2008 Aug;48(8):1582-91.
    PMID: 18656912 DOI: 10.1021/ci700388k
    A group of flavanones and their chalcones, isolated from Boesenbergia rotunda L., were previously reported to show varying degrees of noncompetitive inhibitory activities toward Dengue virus type 2 (Den2) protease. Results obtained from automated docking studies are in agreement with experimental data in which the ligands were shown to bind to sites other than the active site of the protease. The calculated K(i) values are very small, indicating that the ligands bind quite well to the allosteric binding site. Greater inhibition by pinostrobin, compared to the other compounds, can be explained by H-bonding interaction with the backbone carbonyl of Lys74, which is bonded to Asp75 (one of the catalytic triad residues). In addition, structure-activity relationship analysis yields structural information that may be useful for designing more effective therapeutic drugs against dengue virus infections.
  13. Lee WS, Gudimella R, Wong GR, Tammi MT, Khalid N, Harikrishna JA
    PLoS One, 2015;10(5):e0127526.
    PMID: 25993649 DOI: 10.1371/journal.pone.0127526
    Physiological responses to stress are controlled by expression of a large number of genes, many of which are regulated by microRNAs. Since most banana cultivars are salt-sensitive, improved understanding of genetic regulation of salt induced stress responses in banana can support future crop management and improvement in the face of increasing soil salinity related to irrigation and climate change. In this study we focused on determining miRNA and their targets that respond to NaCl exposure and used transcriptome sequencing of RNA and small RNA from control and NaCl-treated banana roots to assemble a cultivar-specific reference transcriptome and identify orthologous and Musa-specific miRNA responding to salinity. We observed that, banana roots responded to salinity stress with changes in expression for a large number of genes (9.5% of 31,390 expressed unigenes) and reduction in levels of many miRNA, including several novel miRNA and banana-specific miRNA-target pairs. Banana roots expressed a unique set of orthologous and Musa-specific miRNAs of which 59 respond to salt stress in a dose-dependent manner. Gene expression patterns of miRNA compared with those of their predicted mRNA targets indicated that a majority of the differentially expressed miRNAs were down-regulated in response to increased salinity, allowing increased expression of targets involved in diverse biological processes including stress signaling, stress defence, transport, cellular homeostasis, metabolism and other stress-related functions. This study may contribute to the understanding of gene regulation and abiotic stress response of roots and the high-throughput sequencing data sets generated may serve as important resources related to salt tolerance traits for functional genomic studies and genetic improvement in banana.
  14. Soo YN, Tan CP, Tan PY, Khalid N, Tan TB
    J Sci Food Agric, 2021 Apr;101(6):2455-2462.
    PMID: 33034060 DOI: 10.1002/jsfa.10871
    BACKGROUND: The popularity of coffee, the second most consumed beverage in the world, contributes to the high demand for liquid non-dairy creamer (LNDC). In this study, palm olein emulsions (as LNDCs) were investigated as alternatives to the more common soybean oil-based LNDCs. LNDCs were prepared via different homogenization pressures (100-300 bar) using different types of oil (palm olein and soybean oil) and concentrations of DATEM emulsifier (5-20 g kg-1 ).

    RESULTS: Increases in homogenization pressure and emulsifier concentration were observed to have significant (P  0.05) differences between the prepared and commercial LNDCs in terms of their color, appearance, and overall acceptability.

    CONCLUSION: Shelf-stable LNDCs with qualities comparable to commercial LNDC were successfully fabricated. Valuable insights into the effects of homogenization pressure, oil type, and emulsifier concentration, as well as functionality and consumer acceptance of the LNDCs when added into black coffee, were obtained. © 2020 Society of Chemical Industry.

  15. Kiat TS, Pippen R, Yusof R, Ibrahim H, Khalid N, Rahman NA
    Bioorg Med Chem Lett, 2006 Jun 15;16(12):3337-40.
    PMID: 16621533
    Boesenbergia rotunda (L.) cyclohexenyl chalcone derivatives, 4-hydroxypanduratin A and panduratin A, showed good competitive inhibitory activities towards dengue 2 virus NS3 protease with the Ki values of 21 and 25 microM, respectively, whilst those of pinostrobin and cardamonin were observed to be non-competitive. NMR and GCMS spectroscopic data formed the basis of assignment of structures of the six compounds isolated.
  16. Md Noh MF, Gunasegavan RD, Mustafa Khalid N, Balasubramaniam V, Mustar S, Abd Rashed A
    Molecules, 2020 Oct 06;25(19).
    PMID: 33036314 DOI: 10.3390/molecules25194567
    Food composition database (FCD) provides the nutritional composition of foods. Reliable and up-to date FCD is important in many aspects of nutrition, dietetics, health, food science, biodiversity, plant breeding, food industry, trade and food regulation. FCD has been used extensively in nutrition labelling, nutritional analysis, research, regulation, national food and nutrition policy. The choice of method for the analysis of samples for FCD often depends on detection capability, along with ease of use, speed of analysis and low cost. Sample preparation is the most critical stage in analytical method development. Samples can be prepared using numerous techniques; however it should be applicable for a wide range of analytes and sample matrices. There are quite a number of significant improvements on sample preparation techniques in various food matrices for specific analytes highlighted in the literatures. Improvements on the technology used for the analysis of samples by specific instrumentation could provide an alternative to the analyst to choose for their laboratory requirement. This review provides the reader with an overview of recent techniques that can be used for sample preparation and instrumentation for food analysis which can provide wide options to the analysts in providing data to their FCD.
  17. Abd-Aziz N, Tan BC, Rejab NA, Othman RY, Khalid N
    Mol Biotechnol, 2020 Apr;62(4):240-251.
    PMID: 32108286 DOI: 10.1007/s12033-020-00242-2
    In the past decade, interest in the production of recombinant pharmaceutical proteins in plants has tremendously progressed because plants do not harbor mammalian viruses, are economically competitive, easily scalable, and capable of carrying out complex post-translational modifications required for recombinant pharmaceutical proteins. Mucuna bracteata is an essential perennial cover crop species widely planted as an underground cover in oil palm and rubber plantations. As a legume, they have high biomass, thrive in its habitat, and can fix nitrogen. Thus, M. bracteata is a cost-efficient crop that shows ideal characteristics as a platform for mass production of recombinant protein. In this study, we established a new platform for the transient production of a recombinant protein in M. bracteata via vacuum-assisted agro-infiltration. Five-week-old M. bracteata plants were vacuum infiltrated with Agrobacterium tumefaciens harboring a plasmid that encodes for an anti-toxoplasma immunoglobulin (IgG) under different parameters, including trifoliate leaf positional effects, days to harvest post-infiltration, and the Agrobacterium strain used. Our results showed that vacuum infiltration of M. bracteata plant with A. tumefaciens strain GV3101 produced the highest concentration of heterologous protein in its bottom trifoliate leaf at 2 days post-infiltration. The purified anti-toxoplasma IgG was then analyzed using Western blot and ELISA. It was demonstrated that, while structural heterogeneity existed in the purified anti-toxoplasma IgG from M. bracteata, its transient expression level was two-fold higher than the model platform, Nicotiana benthamiana. This study has laid the foundation towards establishing M. bracteata as a potential platform for the production of recombinant pharmaceutical protein.
  18. Liew YJM, Lee YK, Khalid N, Rahman NA, Tan BC
    PeerJ, 2020;8:e9094.
    PMID: 32391211 DOI: 10.7717/peerj.9094
    Flavonoids and prenylated flavonoids are active components in medicinal plant extracts which exhibit beneficial effects on human health. Prenylated flavonoids consist of a flavonoid core with a prenyl group attached to it. This prenylation process is catalyzed by prenyltranferases (PTs). At present, only a few flavonoid-related PT genes have been identified. In this study, we aimed to investigate the roles of PT in flavonoid production. We isolated a putative PT gene (designated as BrPT2) from a medicinal ginger, Boesenbergia rotunda. The deduced protein sequence shared highest gene sequence homology (81%) with the predicted homogentisate phytyltransferase 2 chloroplastic isoform X1 from Musa acuminata subsp. Malaccensis. We then cloned the BrPT2 into pRI vector and expressed in B. rotunda cell suspension cultures via Agrobacterium-mediated transformation. The BrPT2-expressing cells were fed with substrate, pinostrobin chalcone, and their products were analyzed by liquid chromatography mass spectrometry. We found that the amount of flavonoids, namely alpinetin, pinostrobin, naringenin and pinocembrin, in BrPT2-expressing cells was higher than those obtained from the wild type cells. However, we were unable to detect any targeted prenylated flavonoids. Further in-vitro assay revealed that the reaction containing the BrPT2 protein produced the highest accumulation of pinostrobin from the substrate pinostrobin chalcone compared to the reaction without BrPT2 protein, suggesting that BrPT2 was able to accelerate the enzymatic reaction. The finding of this study implied that the isolated BrPT2 may not be involved in the prenylation of pinostrobin chalcone but resulted in high yield and production of other flavonoids, which is likely related to enzyme promiscuous activities.
  19. Liew YJM, Lee YK, Khalid N, Rahman NA, Tan BC
    Mol Biotechnol, 2021 Apr;63(4):316-326.
    PMID: 33565047 DOI: 10.1007/s12033-021-00304-z
    Prenylation of aromatic natural products by membrane-bound prenyltransferases (PTs) is an important biosynthesis step of many bioactive compounds. At present, only a few plant flavonoid-related PT genes have been functionally characterized, mainly due to the difficulties of expressing these membrane proteins. Rapid and effective methods to produce functional plant membrane proteins are thus indispensable. Here, we evaluated expression systems through cell-based and cell-free approaches to express Boesenbergia rotunda BrPT2 encoding a membrane-bound prenyltransferase. We attempted to express BrPT2 in Escherichia coli and tobacco plants but failed to detect this protein using the Western-blot technique, whereas an intact single band of 43 kDa was detected when BrPT2 was expressed using a cell-free protein synthesis system (PURE). Under in vitro enzymatic condition, the synthesized BrPT2 successfully catalyzed pinostrobin chalcone to pinostrobin. Molecular docking analysis showed that pinostrobin chalcone interacts with BrPT2 at two cavities: (1) the main binding site at the central cavity and (2) the allosteric binding site located away from the central cavity. Our findings suggest that cell-free protein synthesis could be an alternative for rapid production of valuable difficult-to-express membrane proteins.
  20. Ali MH, Suleiman N, Khalid N, Tan KH, Tseng ML, Kumar M
    Trends Food Sci Technol, 2021 Mar;109:94-102.
    PMID: 34728899 DOI: 10.1016/j.tifs.2021.01.021
    BACKGROUND: The ability of small- and medium-sized enterprises in the food industry (FSMEs) in cultivating resilience against the COVID-19 pandemic is vital food security. However, there is limited supply chain resilience literature to guide FSMEs in overcoming disruptions caused by pandemic.

    SCOPE AND APPROACH: This review aims to provide a broad view of SCRes reactive strategies for FSMEs in dealing with crises in the context of COVID-19. Attention is given to the literature on resilience in other types of supply chain and situated in the context of food settings. The factors are monitored or controlled to contribute to FSME resiliency.Key findings and conclusion: Four quadrants, i.e., (1) rapid with low cost, (2) rapid with high cost, (3) slow with low cost and (4) slow with high cost, are offered based on the limitations and the time needed to react, and the strategies of each quadrant are explained in depth. This review also provides a better understanding of and guidance on reactive strategies for SCRes as options for FSMEs in dealing with the COVID-19 pandemic. This review suggests future directions as extensions based on the logical flow of this review.

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