Presenter’s ID: PC02 Category: Others BIOCOMPUTATIONAL-MEDIATED SCREENING FOR DISCOVERY OF ANTIMELANOGENIC AND ANTIOXIDANT AGENTS FROM Ficus carica L. Chew Wing Xin , Zee Wei Lai, Yin-Quan Tang School of Biosciences, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia. *Corresponding author email address: [email protected] Hyperpigmentation disorders caused by the overproduction of melanin and oxidative stress not only affect skin health but also contribute to psychological consequences such as low self-esteem and social anxiety. The desire to solve hyperpigmentation problems, as well as adverse effects associated with synthetic compounds in commercial skin-whitening products, has led to a growing demand for natural skin-whitening ingredients. Fig fruit (Ficus carica L.) is a promising alternative as it is known to contain various bioactive compounds with excellent antioxidant properties. This study aims to identify safe yet effective antioxidant and antimelanogenic compounds from fig fruit for skin depigmentation purposes. 77 Ficus carica compounds were docked with 4 proteins involved in melanogenesis (receptor tyrosine kinase, tyrosinase-related protein 1, cAMP-response element binding protein, endothelin receptor type-B) and 2 proteins related to oxidative stress generation (mitogen-activated protein kinase, matrix metalloproteinase-1). The best five ligands for each target protein were analysed for their pharmacokinetic characteristics. Compounds that meet the desired criteria were selected for multiple ligand simultaneous docking to examine combined effects. The negative binding affinity values obtained from molecular docking proved the ability of Ficus carica compounds to inhibit melanogenesis and oxidative stress production. Cynaroside is depicted to be the most potent compound as it shows strong binding interactions with most target proteins and exhibits great pharmacokinetics properties. Our study found several compounds derived from fig fruit, especially cynaroside, are potent inhibitors of melanogenesis and oxidative stress. Keywords: hyperpigmentation disorders, fig, molecular docking 100 *
Presenter’s ID: PC03 Category: Others EFFECTS OF HCoV-229E ON HUMAN PLATELET AGGREGATION INDUCED BY COLLAGEN Farah Syazwanie Mohd Zahiruddin , Nadiah Nabilah Mohd Marphy , Nur Tha’iyyah Kamaruzaman , Mohammad Azri Faiq Mohammad , Zetty Nadia Mohd Zain , Zulkefley Othman Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. Department of Medical Science II, Faculty of Medicine and Health Sciences, Universiti Sains Islam Malaysia, Nilai, Negeri Sembilan, Malaysia. *Corresponding author email address: [email protected], [email protected], [email protected] The emergence of COVID-19 as a prevalent respiratory virus has raised concerns regarding its impact beyond respiratory symptoms. Recent studies have suggested that coronavirus infection may affect platelet function. Platelet aggregation plays a crucial role in preventing excessive bleeding and promoting clot formation. This study aims to investigate the effects of HCOV-229E on human platelet aggregation induced by collagen. 20 mL of peripheral blood samples from healthy individuals (n=4) were collected and centrifuged to obtain platelet-rich plasma (PRP) and platelet-poor plasma (PPP). For each well, 100 µL of PRP was co-incubated with 10 µL of HCoV-229E (MOI 0.001) for 30 minutes at 37°C before being added into a new 96-well plate containing various concentrations of collagen in duplicate. Platelet aggregation was determined by measuring absorbance using light transmission aggregometry (LTA) in a microplate reader for 64 cycles at 595 nm. Statistical analysis was performed using GraphPad Prism, and data were expressed as mean ± standard error of the mean (SEM). Platelet aggregation induced by collagen at concentrations of 3.0, 10.0 and 30 µg (15.67 ± 11.09; 41.67 ± 3.32; 57.17 ± 13.62) was decreased to (11.83 ± 6.01; 19.17 ± 10.09; 44.17 ± 15.60) with the addition of HCOV-229E. Although most studies suggested that platelet function is increased following coronavirus infection, our findings showed that collagen-induced platelet aggregation is inhibited in the presence of low virus concentration. The virus might induce changes in platelet receptors or their downstream activation pathways, resulting in decreased sensitivity to collagen. Repeating experiments with higher multiplicity of infection (MOI) is suggested to confirm this pattern of platelet response. As a conclusion, coronavirus infection may affect downstream activation of glycoprotein IV, a major collagen receptor on platelets and may cause platelet dysfunction rather than clotting. Keywords: HCOV-229E, platelet, collagen 101 1 2 1* 1 1* 1 2 2*
Presenter’s ID: PC04 Category: Others EFFECT OF CYTOADHERENCE PROPERTIES OF Plasmodium knowlesi Joo Yie Chin , Wenn-Chyau Lee Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia. Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia. A*STAR Infectious Diseases Labs (A*STAR ID Labs), Agency for Science, Technology and Research (A*STAR), Singapore. *Corresponding author email address: [email protected] The pathogenesis of severe malaria revolves around the cytoadherence properties of Plasmodium-infected red blood cells (IRBCs) within the patient's vasculature. IRBCs can sequester within the microvasculature through several mechanisms to escape the clearance by the immune system, which include the IRBC-endothelial cytoadherence, rosetting, and autoagglutination of IRBCs. The sequestration of IRBCs causes microvasculature obstruction, leading to the development of severe malaria. Insulin growth factor binding protein 7 (IGFBP7), a human-derived protein, has been demonstrated to mediate the cytoadherence events by P. falciparum (the most fatal human malaria parasite). In this project, we investigated the effect of IGFBP7 on the cytoadherence characteristics of P. knowlesi, the potentially fatal zoonotic malaria of increasing prevalence in Southeast Asia. Culturable P. falciparum and P. knowlesi isolates were recruited. Rosetting assay was conducted to assess the impact of IGFBP7 on the cytoadherence properties. IGFBP7 stimulated rosette formation by P. knowlesi in similar manner as that of P. falciparum. Significant rosette stimulation on P. knowlesi was noted at IGFBP7 of working concentrations as low as 50 ng/ml. In addition, the cytoadherence ligand(s) involved in IGFBP7-mediated rosetting by this simian malaria parasite exhibited high trypsin sensitivity. Similar to P. falciparum, IGFBP7-mediated rosetting by P. knowlesi requires the presence of human serum. Keywords: Plasmodium knowlesi, Insulin Growth Factor Binding Protein 7 (IGFBP7), cytoadherence properties 102 1 2 3 1,2 2,3*
Presenter’s ID: PC05 Category: Others PREVALENCE OF INTESTINAL POLYPARASITISM CO-INFECTED WITH MICROSPORIDIA AMONG ROHINGYA SCHOOL CHILDREN IN SELANGOR Wan Muhammad Daud Wan Ali , Nur Raihana Ithnin , Nur Shahira Sulaiman Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia. Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia. *Corresponding author email address:[email protected], [email protected], [email protected] Refugees frequently migrate from areas where infectious diseases are more prevalent and they may have experienced adverse social conditions, inadequate housing facilities, unhygienic lifestyles, poor sanitation and barriers to healthcare access. Due to that, refugees particularly in children are generally more susceptible to contracting any infectious diseases, including intestinal parasitic infections. Concomitant infections of intestinal parasites are very common in developing countries especially in tropical regions. In Malaysia, Rohingya refugees are the most registered refugee population. Most previous studies of intestinal parasitic infections in Malaysia have been conducted in rural communities, with relatively little attention focussed on underprivileged populations such as refugees. These infections can be due to intestinal protozoa (Giardia intestinalis, Cryptosporidium spp., Cyclospora cayetanensis and Entamoeba histolytica/coli) or intestinal helminths (Ascaris lumbricoides, Necator americanus, Trichuris trichiura, Ancylostoma duodenale and Enterobius vermicularis). This study aims to assess the distribution of intestinal polyparasitism co-infected with microsporidia among Rohingya school children in Selangor. Ninety-one Rohingya school children's stools were collected and examined for the presence of intestinal parasites using direct fecal smear, Formol-ethyl acetate sedimentation technique and Modified Wheatley’s Trichrome staining technique. Later, the fecal smear and staining were observed under microscope and confirmed by two expertises. The intestinal parasitic infections among children in this marginalized community showed higher prevalence of intestinal helminths compared to intestinal protozoa. Prevalence rate of polyparasitism was high in Rohingya children. Thus, it is necessary to implement sustainable and effective control measures such as periodic chemotherapy in schools, delivering of reliable health education by emphasizing good personal hygiene practices and proper sanitation as well as ensuring a safe drinking water supply in this population. Keywords: Intestinal Parasites, Microsporidia, Rohingya 103 1 2 1 1 2
Presenter’s ID: PC06 Category: Others SCREENING FOR ANTIBACTERIAL AND ANTIBIOFILM EFFECTS OF SYNTHETIC PEPTIDE PAM-5 ON MULTIDRUG-RESISTANT Escherichia coli Chia Yee Goh, Hawk Leong Yuen Department of Allied Health Sciences, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar 31900, Perak, Malaysia. *Corresponding author email address: [email protected], [email protected] The rising incidence of antibiotic resistance in Escherichia coli is alarming, and biofilm has been recognized as one of the attributing factors to antibiotic resistance, making treatment of bacterial infections become extremely challenging. Therefore, there is an urgent demand for novel antibacterial and antibiofilm agents to combat this bacterium. Antibacterial peptides (ABPs) have been reported as promising candidates of alternative antibacterial agents against many bacterial infections. However, not all the ABPs possess antibiofilm effects. In this study, a 15-mer synthetic peptide, PAM-5, was screened for its antibacterial and antibiofilm effects on Escherichia coli (E. coli). Using microbroth dilution assay, a clinical extended spectrum beta lactamases (ESBL)-producing E. coli was treated with increasing concentrations of PAM-5 (2 µg/mL to 256 µg/mL), and the minimal bacteriostatic/bactericidal concentrations (MICs and MBCs) were determined. Antibiofilm effects of PAM-5 were evaluated using biofilm inhibition assay and biofilm eradication assay. For inhibitory assay, E. coli was loaded onto wells of 96-well microtiter plate precoated with PAM-5 at the same range of concentrations, followed by quantifying the amount of biofilm mass using crystal violet (CV) staining on the next day. For eradication assay, mature bacterial biofilm was established in the wells, followed by treatment with PAM-5 at the same concentrations. The biofilm mass was accessed by CV staining, while the metabolic activity of the treated biofilm was accessed using MTT stain. PAM-5 exhibited promising antibacterial effects towards planktonic ESBL-producing E. coli at the MIC of 8 µg/mL and MBC of 16 µg/mL. Interestingly, PAM-5 was also shown able to inhibit biofilm formation at the MBIC50 of 2 µg/mL, while eradicating mature biofilm at the MBEC50 of 4 µg/mL. In conclusion, PAM-5 was shown to possess promising antibacterial effects towards planktonic ESBL-E. coli, as well as inhibiting biofilm formation and eradicate mature biofilm formed by the bacterium. Keywords: synthetic peptide, antibacterial activity, antibiofilm activity 104
Presenter’s ID: PC07 Category: Others EFFECTS OF HUMAN CORONAVIRUS 229E (HCoV-229E) ON HUMAN PLATELET AGGREGATION INDUCED BY ADP Nadiah Nabilah Mohd Marphy , Farah Syazwanie Mohd Zahiruddin , Nur Thai’iyyah Kamaruzaman , Mohammad Azri Faiq Mohammad , Zetty Nadia Mohd Zain , Zulkefley Othman Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. Department of Medical Science II, Faculty of Medicine and Health Science, Universiti Sains Islam Malaysia, Nilai, Negeri Sembilan, Malaysia. *Corresponding author email address: [email protected], [email protected] Human Coronavirus infections have garnered significant attention especially after COVID-19 pandemic. While these viruses were previously known for causing mild respiratory illnesses like common cold, emerging research suggests potential cardiovascular implications associated with some strains. Recent studies highlight interactions between coronaviruses and blood coagulation, leading to coagulopathies. Platelet agonists, like ADP, play crucial roles in platelet activation and coagulation. However, the specific impact of HCoV-229E on ADP-induced platelet aggregation remains unexplored, necessitating further investigation. This study aims to investigate the effects of HCoV-229E on human platelet function determined by platelet aggregation activated by ADP. Healthy human peripheral blood was collected (N=3) and centrifuged to obtain Platelet Rich Plasma (PRP) and Platelet Poor Plasma (PPP). HCoV-229E was propagated in MRC-5 lung fibroblast cells followed by plaque assay for virus titration. Platelet agonist, ADP was prepared with increasing concentration, 0.1µM, 0.3µM, 1µM, 3µM, 10µM, and 30µM in a 96-well plate. PRP was pre-incubated with HCoV-229E (MOI 0.001) for 30 minutes at 37˚ C, following the addition into a 96-well plate containing ADP. Platelet aggregation assay was performed using the modified Light Transmission Aggregometry (LTA) method, and the absorbance was measured at wavelength of 595 nm for 64 cycles. The result was analysed using GraphPad Prism 10.2.2. HCoV-229E increases platelet aggregation induced by various ADP concentrations; 1µM (24.8 ±18.2%), 3µM (20.7 ±9%), 10µM (39 ±5.7%), and 30µM (51.8 ±4.8%), as compared to control 1µM (7.5 ±2.8%), 3µM (12 ±2%), 10µM (29.8 ±4.8%), and 30µM (38.5 ±2.2%). These findings showed there is an increase of platelet aggregation induced by ADP in the presence of HCoV-229E, suggesting a potential role of coronavirus in exacerbating thrombotic events. These data suggest that HCoV-229E may increase platelet aggregation induced by ADP, highlighting a potential link between coronavirus infections and thrombotic risk. Keywords: Coronavirus, ADP, platelet 105 1 2 1* 1 1 2 2 1*
Presenter’s ID: PC08 Category: Others ESTABLISHMENT OF GAMETOCYTE PRODUCTION IN Plasmodium knowlesi IN VITRO CULTURE Lam, Sherly Wai Ying , Yee Ling, Lau , Fei Wen, Cheong Biomedical Science Department, Faculty of Medicine, Universiti Malaya, Federal Territory of Kuala Lumpur, 50603, Malaysia. Department of Parasitology, Faculty of Medicine, Universiti Malaya, Federal Territory of Kuala Lumpur, 50603, Malaysia. *Corresponding author email address: [email protected] Plasmodium knowlesi is identified as the fifth human malaria of zoonotic origin and it is endemic within Malaysia. The life cycle of Plasmodium spp. undergoes asexual stages of rings, trophozoites, merozoites, and schizonts and some commit irreversibly into gametocytogenesis to form sexual stages (gametocytes). Gametocytes are transmitted from humans to Anopheles mosquitoes during a blood meal to complete its life cycle. The present study aims to induce gametocytogenesis using conditioned media (CM) in the P. knowlesi UM04-H (Universiti Malaya) line. CM is a media consisting of accumulated metabolic waste products from the parasite culture with depletion of nutrients, thus it is postulated to be able to induce stress on the synchronized asexual stages to commit into gametocytogenesis. CM was collected from P. knowlesi cultures during the parasitemia of 3% (termed 3% CM) and 6% (termed 6% CM) each. During the induction, the parasites were incubated in 90% (vol/vol) CM, gas composition of 90% , 5%, and 5%, and the outcome of gametocytogenesis was observed at 3 time points of 36 hours, 41 hours, and 48 hours post-incubation via microscopic examination of thin blood smears. A total of 6 biological replicates were included in each round of the experiment, and the entire experiment was repeated for another 2 rounds (total 3 technical replicates). Data analysis for the remaining technical replications is still on-going. Based on the findings from one round of experiment, no gametocytes were observed at 6% CM and 3% CM at all time points. This could be due to the lack of optimization on the experiment settings, where the parasitemia and concentration of CM used in the present study could be insufficient/inappropriate to induce stress on UM04-H. Statistical analysis by Repeated Measure Two-Way ANOVA and Tukey’s multiple comparisons test revealed significant differences (p < 0.0001) in conditioned media effects. The difference between 3% CM and 6% CM at 36h and 48h is significant (p = 0.0176, p = 0.0085). Parasitemia at each time point is significantly different (p ≤ 0.05 – 0.001) between the CM with their respective controls (except for 6% CM with its control at 36h due to outliers), signifying that CM does affect the fold change of the parasites. Overall, CM is unable to induce gametocytogenesis efficiently in the present study and more future studies are required to optimize the protocols. Keywords: Gametocytes, Conditioned Media, Induction 1* 2 2 1 2 106
Presenter’s ID: PC09 Category: Others Candida glabrata GENE EXPRESSION RESPONSE UPON ENGULFMENT BY MACROPHAGES Nur Amisya Safia Mohd Fadzil , Leslie Thian Lung Than , Elysha Nur Ismail Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia. Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia. Candida glabrata, also recognized as Nakaseomyces glabratus, is a non-dimorphic yeast that falls within the Nakaseomyces genus and the Fungi Imperfecta class. Unlike other Candida species, C. glabrata exclusively appears as small blastoconidia and does not develop pseudohyphae at temperatures exceeding 37°C. The increasing focus on the growing incidence of candidiasis in recent years is primarily attributed to C. glabrata due to its high resistance to the effectiveness of azoles therapy. Notably, when C. glabrata is internalized by macrophages, it can survive and multiply inside the host, thereby prolonging the duration of the infection. This study aims to examine the alterations in ICL1 and MNN2 gene expression patterns when C. glabrata interacts with macrophages. In this investigation, the differentiation of monocytes into macrophages will be achieved through exposure to the phorbol ester PMA. Subsequently, C. glabrata will be co-cultured with THP-1 macrophages at a human macrophage to fungal ratio of 1:10. The co-culture will be incubated at 37°C for varying durations (0 hours, 0.5 hours, 2 hours, and 48 hours) to observe changes in gene expression at different time points. Total RNA will be extracted from C. glabrata from inside the macrophage, and RT-qPCR will be used to measure gene expression. The anticipated outcome of this study is an observed upregulation in ICL1 and MNN2 gene levels. Upregulation of the two genes lead to altered metabolism and cell wall modifications that subsequently lead to enhanced capacity for survival in the host environment. In conclusion, understanding changes in gene expression is crucial in unraveling the complex host-pathogen interaction. By examining the genes that are altered in response to C. glabrata engulfment, insights into the molecular mechanisms underlying the infection can be further defined. Keywords: Candida glabrata, THP-1 macrophages, RT-qPCR 107 1 2 1 2 1
Presenter’s ID: PC10 Category: Others INSECTICIDE SUSCEPTIBILITY PROFILE OF WOLBACHIA-INFECTED Aedes aegypti Ahnaf Akram Anuar , Zulhisham Zulzahrin , Wenn-Chyau Lee Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia. Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia. A*STAR Infectious Diseases Labs (A*STAR ID Labs), Agency for Science, Technology and Research (A*STAR), Singapore. *Corresponding author email address: [email protected] Dengue fever is a significant mosquito-borne illness, with Aedes aegypti serving as one of its major vectors, particularly in the urban areas. To control the spread of this potentially fatal infection, Ae. aegypti infected with Wolbachia (henceforth known as WIA) have been released into the environment in several countries, including Malaysia. However, various biological aspects, such as the effect of Wolbachia infection on the insecticide susceptibility of the mosquitoes, have remained to be elucidated thoroughly. This study evaluated the susceptibility of larvae produced by WIA and Wolbachia-uninfected Ae. aegypti (henceforth known as WUA) to insecticides from four major classes, namely temephos (an organophosphate), permethrin (a pyrethroid), propoxur (a carbamate) and dichlorodiphenyl-trichloroethane (DDT, an organochlorine). A total of 5760 laboratory-reared larvae of WIA and WUA were recruited for the study. The mortality rates were determined after 24 hours of insecticide exposure. The larvae that survived the insecticide exposure were monitored to evaluate their growth and metamorphosis. WIA demonstrated lower susceptibility to temephos, permethrin, and DDT, whereas the WUA were less susceptible to propoxur. Furthermore, WIA showed higher success of metamorphosis into pupal and adult stages post-exposure, as compared to the WUA, with the exception of propoxur exposure. There was no significant difference in the speed of metamorphosis among the larvae that survived the insecticide exposure. Our study demonstrated altered larval susceptibility profiles of WIA and WUA to different commonly used insecticides. Keywords: Wolbachia, Aedes aegypti, insecticide 108 1 2 1,2 2 2,3*
109 Presenter’s ID: PD01 Category: Natural Products THE ANTIVIRAL EFFECTS OF DIFFERENT TYPES OF STINGLESS BEE PROPOLIS EXTRACTS AGAINST INFLUENZA A VIRUS Hui Yee Ng , Chai Xin Yu , Kai Xin Cheah , Wan Iryani Wan Ismail , Hui Yee Chee , Chau Ling Tham Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, Kuala Nerus Terengganu, Malaysia. Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. Honeybee propolis is known as a functional food with scientifically proven antiviral effects against the Influenza A Virus (IAV). Stingless bees produce more propolis (64%) than honey and beebread, however, the antiviral effect of stingless bee propolis remains underexplored. This study aims to investigate the antiviral activities of the stingless bee propolis extracts (SBPEs) as a whole along with its five types extracted from different parts of a beehive against IAV (A/Puerto Rico/8/34) (PR8) infection in vitro. It is hypothesised that SBPEs can suppress IAV infection in vitro. Six SBPEs were obtained from ethanolic extracts of a beehive from Heterotrigona itama. Non-cytotoxic concentrations (NCTCs) of SBPEs on A549 human pulmonary epithelial cells were determined using an MTT assay. Cytopathic effect (CPE) assay was performed to examine the morphological changes in the IAV-infected cells after treatment with NCTCs of SBPEs, followed by an MTT-based CPE reduction assay to determine the antiviral effect and selectivity index. The antiviral mechanism was accessed via pre-treatment, posttreatment, and co-treatment of SBPEs with IAV infection. Virus level in the culture supernatant was quantified via TCID50. Data were analysed using One-way ANOVA, followed by post hoc Dunnett’s test. According to the MTT results, pillars were noncytotoxic to A549 cells at the concentrations of 25, 12.5, and 6.25ug/mL (CC50= 51.40μg/mL); cerumen, pot, and involucrum NCTCs’ 6.25, 3.125, 1.563ug/mL with CC50 values of 11.12ug/mL, 24.73μg/mL and 13.59μg/mL respectively; batumen’s NCTCs were at 3.125, 1.563, 0.781ug/mL (CC50= 5.999μg/mL) (p<0.05). Pillars show the least cytotoxic effect on A549 cells as compared to other SBPEs. While cytotoxicity effects on A549 cells have been determined, antiviral effects of SBPEs on IAV-infected A549 cells remain to be explored. 1 2 3 1 1 1 2 3 1
Presenter’s ID: PD02 Category: Natural Products COMPARATIVE ANALYSIS OF RESVERATROL FROM VARIOUS SOURCES IN INHIBITING DENGUE VIRUS REPLICATION Mok Xin Hui*, Chin Kim Ling Department of Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia. *Corresponding author email address:[email protected] Dengue virus (DENV), a mosquito-borne flavivirus, which can cause dengue fever and lead to death. Over the past decade, there has been a global upsurge in dengue cases. The antiviral effects of resveratrol (RES) against viral infections, including DENV, have been reported previously. However, the antiviral effects of different sources of RES against DENV have not been explored yet. Therefore, this study investigated the effectiveness of three sources of RES, which are Japanese knotweed from Dong Foong Manufacturing Sdn Bhd. (JK), bushy knotweed from Sigma-Aldrich (S), and grape skin from Veri-te® Resveratrol by Evolva (V), in suppressing DENV replication in vitro. The RES cytotoxicity towards human hepatocellular carcinoma Huh7 cells was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium (MTS) assay. Subsequently, a post-infection assay was performed to investigate the antiviral effects of the three RES sources on DENV replication. DENV titers were determined using a focus-forming assay (FFA). The findings showed that S obtained the highest 50% cytotoxicity concentration (CC50), 2782 µM and maximal nontoxic dose (MNTD), 472.2 µM, suggesting that it has a broader therapeutic window compared to JK and V. The antiviral effects of all three RES sources against DENV were shown to be dose-dependent, with 100% inhibition at 80 μM. S demonstrated the highest selectivity index (SI) of 113.97, indicating that it exhibited the most effective inhibition of DENV at lower concentrations. Further research in animal models is required to fully understand the significance of RES in dengue treatment. Keywords: resveratrol sources comparison, dengue virus, antiviral effects 110
Presenter’s ID: PD03 Category: Natural Products THE EFFECT OF POLYMERIC MICELLES ENCAPSULATING Sesbania grandiflora LEAF EXTRACT ON THE ANTIBACTERIAL ACTIVITY OF GRAM POSITIVE AND GRAM NEGATIVE BACTERIA Narmitha A/P Sathasivam , Elysha Nur Ismail , Seri Narti Edayu Sarchio , Zulkefley Othman , Suhaili Shamsi Department of Biomedical Science, Faculty of Medicine and Health Science, Universiti Putra Malaysia, Malaysia. Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Malaysia. *Corresponding author email address: [email protected] Sesbania grandiflora (S. grandiflora) leaves are rich in alkaloids, glycosides, flavonoids and tannins, exhibiting potent antioxidant, antibacterial and anti-inflammatory properties. Despite these therapeutic properties, the use of S. grandiflora extract (SGE) as a therapeutic agent and in clinical practices is limited because of its low solubility and stability. To address these limitations, a nanoparticle system encapsulating the SGE is designed using a polymeric micelle known as Pluronic F127 (NanoSGE). Previous studies of NanoSGE were generally focused on evaluating the toxicity in the silkworm model and the antibacterial activity against only one strain of bacteria, which is S. aureus. Reports on the antibacterial activity of NanoSGE on different strains of bacteria are low. The aim of this study is to assess the antimicrobial properties of NanoSGE against Gram-positive bacteria, S. aureus and Gram-negative bacteria, E. coli. The crude extract of the leaves of S. grandiflora was obtained via maceration in 80% ethanol. SGE concentration was determined using UV-Vis Spectrophotometry and LC-MS/MS. NanoSGE is produced by a thin dry film method. The characterization of NanoSGE involved FTIR, FESEM, DLS and loading efficiency. In Vitro antibacterial studies utilized the agar well diffusion and broth microdilution methods to assess the NanoSGE, the crude leaf extract, and the unloaded PF127 against the Gram-positive and Gram-negative bacteria. The NanoSGE will exhibit a bigger zone of inhibition and a lower MIC and MBC in comparison to the crude extract against S. aureus and E.coli while the unloaded PF127 will not exhibit antibacterial effect. The new nanoformulation is believed to improve the antibacterial efficacy, implying that it could be used to overcome the limits of SGE. Keywords: Sesbania grandiflora, nanoencapsulation, antimicrobial activity. 111 1 2 1* 1 1 1 2
Presenter’s ID: PD04 Category: Natural Products OPTIMIZATION IN EXTRACTION AND CHARACTERIZATION OF CHITOSAN FROM Aspergillus niger Nur Dyana Syazwanie binti Dedy Chandra , Nur Syahmina Rasudin School of Health Sciences, University of Science Malaysia, 16150, Kubang Kerian, Kelantan. *Corresponding author email address: [email protected] Chitosan is a deacetylated derivative of chitin linked to β-(1-4) d-glucosamine and Nacetyl-d-glucosamine. It is abundant in nature, such as crustaceans, fungi, and exoskeletons. Due to its unique properties, such as biodegradability and nontoxicity, chitosan has many applications in various industries, such as medicine and agriculture. The objective of this study is to determine the significant mean difference in the dry weight of chitosan between different incubation temperatures and time. Additionally, the study also was conducted to find out the significant mean difference in the degree of deacetylation of chitosan between different incubation temperatures and times. In this project, isolates of Aspergillus niger were cultured on PDA agar for several days, and the cultivated fungal mycelium underwent alkaline and acid treatment to obtain chitosan. Four incubation temperatures (90°C, 98°C, 110°C and 121°C) and four incubation times (15, 20, 25 and 30) minutes were used in the alkaline treatment. The results showed that the incubation temperature affected both the dry weight and the deacetylation level of chitosan (p<0.05). Meanwhile, incubation time did not affect the level of deacetylation and dry weight (p>0.05). The highest chitosan production was obtained at an incubation temperature of 121°C and an incubation period of 30 minutes (157.10 mg). In conclusion, the optimum temperature to get the highest number of chitosan is 121°C and the incubation period is 30 minutes. Keywords: Chitosan extraction, Aspergillus niger, fungal chitosan 112 *
Presenter’s ID: PD05 Category: Natural Products ANTIOXIDANT ACTIVITY AND CYTOTOXIC EFFECT OF TRADITIONAL CHINESE MEDICINE (TCM) DECOCTION Teoh Chai Wen , Sangeetha Arullappan Department of Allied Health Sciences, Faculty of Science, Universiti Tunku Abdul Rahman (UTAR), Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia. *Corresponding author email address: [email protected] Traditional Chinese Medicine (TCM) decoction has drawn great attention as a complementary medicine towards cancer treatment, primarily to alleviate the side effects and to sensitize patients’ response towards conventional cancer therapy like chemotherapy and radiotherapy. In this study, the TCM decoction was provided by the Traditional and Complementary Medicine (T&CM) Centre, UTAR Hospital and was evaluated for the presence of phytochemicals, antioxidant activity and cytotoxic effect. The TCM decoction contained a total of ten herbs namely Hedyotidis Herba, Scutellaria barbata, Prunellae Spica, Coicis Semen, Sparganii Rhizoma, Curcumae Rhizoma, Fritillariae thunbergii Bulbus, Paridis Rhizoma, Solanum nigrum, and Cremastrae Pseudobulbus Pleiones Pseudobulbus. The presence of phytochemicals in the TCM decoction and its polarity was detected via phytochemical analysis and thin layer chromatography. The antioxidant and cytotoxic effects of the TCM decoction were evaluated using DPPH and MTT assays, respectively. In phytochemical analysis, TCM decoction was found to comprise mainly of flavonoids, phenolic compounds, glycosides, saponins, and tannins, while glycosides, quinones and terpenoids were not detected. The TCM decoction has also shown a strong antioxidant activity with EC50 value of 0.0256 ± 5.193 mg/mL. In MTT assay, no cytotoxicity was observed by the TCM decoction on leukemic cells (K562) at both 24- and 48-hours treatment which could be attributed to the nature of the individual components in TCM decoction, whereby most components were prescribed to alleviate the side effects as well as some underlying complications of the patients and very limited components were prescribed for anticancer activity. The TCM decoction are potential antioxidant agent but not a cytotoxic agent against leukemic cell line (K562). Further studies on the TCM decoction are crucial to evaluate its effectiveness as suitable medication in the treatment of cancers. Keywords: Traditional Chinese Medicine (TCM), DPPH assay, MTT assay 113 *
Presenter’s ID: PD06 Category: Natural Products EVALUATING FOR THE TOXICITY OF NANOENCAPSULATED Sesbania grandiflora ETHANOLIC EXTRACT ON ZEBRAFISH EMBRYOS Sitinurshahfika Abdullah , Seri Narti Edayu Sarchio , Suhaili Shamsi , Elysha Nur Ismail Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, 43400, Malaysia. Laboratory of Animal Biochemistry and Biotechnology, Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, 43400, Malaysia. *Corresponding author email address: [email protected], [email protected] While biotechnology shows promise for enhancing ethnopharmacological research through means like nanoencapsulation, which could expedite the progress and effectiveness of therapeutic plant-derived medicines, uncertainties remain regarding the optimal implementation of such complex techniques. Sesbania grandiflora (SG), also known as vegetable hummingbird, is a plant that possesses antibacterial, anthelmintic, and antineoplastic properties. This research employs nanoencapsulation for improved drug delivery, offering a less invasive method such as oral administration and enhancing drug delivery efficiency. Specifically, this study is the first to employ nanoencapsulation to reduce the toxicity of S. grandiflora ethanolic extract (SGE) during embryonic development. Therefore, zebrafish embryos are ideal for toxicity testing because of their rapid development, transparency, and approximately 70% genetic similarity to humans. Previous research on SG-loaded Pluronic nanoformulation (NanoSG) focused on the pluronic type and concentration of pluronic. There have been publications that emphasise SG toxicity, however, research on nanoencapsulation to alleviate S. grandiflora ethanolic extract (SGE) toxicity in embryonic developmental stages is limited. The aim of this study is to evaluate the potential toxicity effects of NanoSGE on zebrafish (Danio rerio) embryos. It is hypothesised that the NanoSGE has less toxicological effects in the zebrafish (Danio rerio) embryo model than in non-encapsulated. SGE leaves' crude extract was obtained using an 80% ethanol maceration process, followed by quantification of total phenolics using spectrophotometer. A nanoformulation of SGE will be synthesised using a dry thin film method. The NanoSGE, pluronic and SGE will be used to evaluate the toxicity of zebrafish embryos (less than 24 hours post-fertilization). All experiments will be triplicated. The observations on mortality, hatching rate, heart rate and tail formation were made every 24 hours. Statistical analysis of the data will involve utilization of twoway analysis of variance methodology (ANOVA) and subsequent application of Tukey’s post hoc testing parameters within the SPSS V29 software environment for examination of outcomes. This study expects that there is lower toxicity of NanoSGE compared to nonencapsulated SGE when tested on zebrafish (Danio rerio) embryos which could contribute to the safer development of therapeutics derived from S. grandiflora. Keywords: Sesbania grandiflora, toxicity, zebrafish embryo 114 1 2 1 1* 1* 2
Presenter’s ID: PD07 Category: Natural Products THE ANTIOXIDANT PROPERTIES AND TOXICITY EVALUATION OF Ostodes pauciflora MERR. SEED EXTRACT (KOP NUTS) Muizzuddin bin Jamaluddin , Caryn Khoo Zhi Hui , Liza Noordin , Noraini Abdul Ghafar , Wan Amir Nizam Wan Ahmad Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia. Physiology Department, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia. *Corresponding author email address: [email protected] Traditionally, Ostodes pauciflora Merr seed (Kop nut) has been used by Sarawakians to lower their blood sugars. Diabetes mellitus is closely linked to the overproduction of reactive oxygen species, leading to oxidative stress. Despite its extensive consumption, there are limited studies and research regarding this plant's antioxidant properties and toxicology profiles. This study determined the antioxidant properties of O. pauciflora seed oil extracts (OPIE) and their toxicology profiles. OPIE was processed using the Soxhlet method and diethyl ether extraction. OPIE's in vitro antioxidant activity was determined using a 1,1- Diphenyl-2-picrylhydrazyl (DPPH) assay. The toxicity evaluation of Kop nut was done by using brine shrimp lethality assay (BSLA). The in vivo acute oral toxicity study was further evaluated on five female rats using five different concentrations of OPIE (55 mg/kg, 175 mg/kg, 550 mg/kg, 1000 mg/kg and 2000 mg/kg) following the OECD 425 guidelines. There was high in vitro antioxidant activity of OPIE, at 68.51%, with an IC50 of 7.965 µg/ml. The BSLA results suggested LC50 of more than 10000 ug/ml. No mortality was observed at the highest dose of OPIE (2000 mg/kg) in the acute study. In addition, no abnormal behaviour and changes in body weight were observed. This study shows that Kop nuts have high antioxidant properties and are safe to consume. With further study, it can be considered as one of the potential antidiabetic agents due to its antioxidant activity. Keywords: Kops nuts, antioxidant, toxicity 115 2 1 1 1 1 1* 2
Presenter’s ID: PD08 Category: Natural Products NANOENCAPSULATION OF Moringa oleifera LEAF EXTRACT (NANOMOLE) USING THIN DRY FILM METHOD: SYNTHESIS, CHARACTERISATION AND TOXICITY ASSESSMENT USING ZEBRAFISH (Danio rerio) MODEL Intan Nurzulaikha Abdul Zahid , Suhaili Shamsi , Elysha Nur Ismail , Seri Narti Edayu Sarchio Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. Department of Biochemistry, Faculty of Biotechnology and Biomolecular, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. *Corresponding author email address: [email protected] Moringa oleifera, locally known as Kelor is a recognised medicinal plant in tropical countries including Malaysia. The plant is valuable in pharmaceutical fields due to the presence of various therapeutic bioactive compounds. Its leaves specifically contain many benefits to human consumption including anticancer properties, breast milk stimulation and immunity enhancement. Despite these benefits, there remains a gap in the research regarding M. oleifera leaf extract (MOLE) utilisation in medical treatments, particularly its toxicity profile. This study aims to extract M. oleifera leaf followed by the assessment of its toxicity profile on zebrafish (Danio rerio) embryogenesis including survival rate, heart rate, hatching rate,and morphology development. M. oleifera leaves were collected at Bukit Katil, Melaka and sent to Institute of Bioscience (IBS), UPM for identification. Once its voucher number was received, its extraction proceeded. Overnight macerations using 80% (v/v) ethanol was performed and then proceeded with freeze drying. For toxicity assessment, zebrafish embryos (n=10-20; 24 hr post fertilisation (hpf)) will be exposed to six different concentrations of MOLE ranging between (5-400 μg/mL) for 96 hr of exposure. Embryos were closely monitored daily for survival rate, hatching rate, heart rate, and embryonic development. E3 media (embryo media) was used as control. MOLE treatment across the three time points showed no significant difference in zebrafish survival rate with no delayed effect on hatching rate. However, the heart rate of embryos was significantly affected at 25 µg/mL and 50 µg/mL concentrations at 24 hr post-treatment. Abnormal embryo development (scoliosis) was observed in groups with >25 µg/mL of MOLE. The toxicity effects of MOLE towards the zebrafish embryos could potentially be due to the length of exposure, concentration difference and the levels of phytochemicals in MOLE such as saponins, tannins, vitamins and phenolic acids. It is revealed that MOLE displayed concentration- and time-dependent toxicity response with more than >50% embryos surviving at highest concentration, up to 72 hr post-treatment. Keywords: Nanoformulation, Moringa oleifera, zebrafish embryo 1 2 1 2 1 1* 116
Presenter’s ID: PD09 Category: Natural Products ANTIOXIDANT ACTIVITY AND CYTOTOXIC EFFECT OF LEMONGRASS ESSENTIAL OIL Tan Jing Ming Utilisation of natural products has become the growth engine in the pharmaceutical industry. Lemongrass essential oil is an aromatic liquid extracted from the leaves and stems of Cymbopogon citratus. Traditionally, lemongrass essential oil is used as insecticide, pain reliever, fever reducer, and antidepressant. Qualitative phytochemical analysis was performed to detect the presence of secondary metabolites in the essential oil. Thin layer chromatography (TLC) was carried out to determine the polarity of the components in lemongrass essential oil. Additionally, antioxidant activity and cytotoxic effect of lemongrass essential oil was evaluated using DPPH and MTT assays, respectively. Based on the results, alkaloids, flavonoids, glycosides, saponins, and terpenoids were present in lemongrass essential oil. Oppositely, phenolic compounds, tannins and quinones were not detected. Only a single spot was formed on the TLC plate and the lemongrass essential oil contains more polar compounds than non-polar compounds based on the increasing Rf values from 0.31 to 0.93. Lemongrass essential oil was able to scavenge DPPH free radicals with an EC50 value of 590.50 ± 9.001 μg/mL. In MTT assay, lemongrass essential oil showed no cytotoxicity on both the normal Vero and K562 cells with the IC50 values of 630.10 ± 17.130 μg/mL and 805.00 ± 19.900 μg/mL, respectively at 48-hours. In a nutshell, the lemongrass essential oil is a potential antioxidant agent. Future studies can be conducted by determining the cytotoxic effect of lemongrass essential oil on distinct cancer cells. 117
Presenter’s ID: PD10 Category: Natural Products NANOENCAPSULATION OF Moringa oleifera LEAF EXTRACT (NANOMOLE) USING THIN DRY FILM METHOD: SYNTHESIS, CHARACTERIZATION AND ASSESSMENT OF ANTIBACTERIAL ACTIVITIES AGAINST METHICILLINRESISTANT Staphylococcus aureus (MRSA) Nur Liyana Daud , Suhaili Shamsi , Elysha Nur Ismail , Nurshahira Sulaiman , Seri Narti Edayu Sarchio Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. Department of Biochemistry, Faculty of Biotechnology and Biomolecular, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia. *Corresponding author email address: [email protected] Methicillin-resistant Staphylococcus aureus (MRSA) presents a substantial nationwide health risk due to its resistance to conventional antibiotics. Researchers are currently investigating new methods to address this pressing issue. One such approach involves the usage of herbal medicine. Among the prospective herbs, Moringa oleifera leaf extract (MOLE) has demonstrated potential in combating bacterial infections. This study aims to examine the antibacterial effects of 80% ethanolic leaf extracts of Moringa oleifera against methicillin-resistant and susceptible Staphylococcus aureus (MRSA and MSSA). The MOLE was obtained by maceration using 80% ethanol as the solvent, followed by concentration with a rotary evaporator and lyophilization into powder form. The antibacterial activity of the crude extract was evaluated using the Kirby-Bauer disc diffusion method. Five different concentrations of MOLE (50 mg/ml, 100 mg/mL, 200 mg/mL, 400 mg/mL, and 800 mg/mL) were tested against MRSA and MSSA. MOLE exhibited significant dose-dependent antibacterial activity against both MRSA and MSSA strains, with higher concentrations demonstrating greater efficacy. Notably, at a concentration of 800 mg/ml, MOLE displayed antibacterial activity comparable to the positive control for MRSA. Possible mechanisms underlying MOLE's differential effect against MRSA and MSSA strains include cell wall alterations, efflux pump systems, and synergistic interactions of bioactive compounds. The antibacterial activities are most likely due to the presence of phytochemicals such as flavonoids and tannins that inhibit bacterial growth. Data from this study strongly suggest that MOLE exhibits antibacterial activity against both MSSA and MRSA with the greatest zones of inhibition noted at 800 mg/mL. Current investigations into nanoencapsulated MOLE (nanoMOLE) are being conducted with the goal of improving the stability and efficacy of its antibacterial applications. Keywords: Moringa oleifera, Methicillin-resistant Staphylococcus aureus, Nanoformulation 1 2 1 2 1 1 1* 118
Presenter’s ID: PD11 Category: Natural Products IMPACTS OF STINGLESS BEE HONEY ON THE MORPHOLOGY INTACTNESS OF Escherichia coli Min Jun Lam, Wen Jie Ng Department of Allied Health Sciences, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar, Malaysia. *Corresponding author email address: [email protected], [email protected] The emergence of antibiotic-resistant bacteria underscores the need for effective alternative antibacterial agents. Multidrug-resistant bacteria especially Escherichia coli have been shown to exhibit a high prevalence of infection and mortality. Even though stingless bee honey has been recognized for its antibacterial properties, its impacts on the morphology of E. coli remain poorly understood. The main objective of this study was to investigate the changes in morphological properties of E. coli including multidrug-resistant clinical isolate after being treated with stingless bee honey. The inhibitory and bactericidal effects of stingless bee honey on E. coli were determined with agar-well diffusion and broth dilution assays. Geniotrigona thoracica honey was found to show greater inhibitory and bactericidal effects against E. coli, compared with Heterotrigona itama honey. The protein content was quantified to determine the leakage of intracellular substances by treating E. coli. The impact of G. thoracica honey on the membrane potential and membrane integrity of E. coli were further assessed using DiBAC4(3) and propidium iodide fluorescent dyes. The results suggested the ability of stingless bee honey to depolarize and destruct the membrane of E. coli. Scanning electron microscopy also revealed morphological alteration and destruction of bacterial cells upon exposure to the stingless bee honey. Overall, the outcomes of this study suggested G. thoracica honey could be a potential alternative against antibiotic-resistant E. coli. Keywords: stingless bee honey, antibiotic-resistant, bactericidal mechanism 119
Presenter’s ID: PD12 Category: Natural Products EFFECTS OF MELON MANIS TERENGGANU PEEL POWDER ON CELL PROLIFERATION AND MORPHOLOGICAL CHANGES IN HUMAN FOETAL OSTEOBLAST CELL LINE (hFOB 1.19) Hermizi Hapidin , Evon Koay Yi Wen , Sakinah Harith , Ong Ying Qian Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia. Faculty of Health Sciences, Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia. Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia. *Corresponding author email address: [email protected] Melon Manis Terengganu (MMT) peel powder is rich in bioactive compounds, vitamins, and minerals, suggesting potential health benefits, particularly for bone health. However, its effects on human foetal osteoblast cells (hFOB 1.19) are largely unexplored. This study aimed to investigate the effects of MMT peel powder on cell proliferation and morphological changes in the hFOB 1.19 cells. hFOB 1.19 cells were cultured in complete Dulbecco’s modified Eagle F12 medium (DMEM F12) and treated with various concentrations of MMT peel powder. The half maximal effective concentration (EC50) was determined using the MTT assay. Cell proliferation assays were conducted over 7 days, and morphological changes were observed under an inverted microscope on days 1, 3, and 7 post-treatments. The EC50 for hFOB 1.19 cells treated with MMT peel powder was 1.404 µg/mL, demonstrating superior efficacy compared to the control drug, pamidronate (IC50 of 3.279 µg/mL). By day 7, the number of cells treated with MMT peel powder significantly exceeded that of the control groups. Microscopic observation revealed confluent and healthy cells with polygonal shapes. MMT peel powder effectively enhanced cell proliferation and induced favorable morphological changes in hFOB 1.19 cells. Its superior efficacy compared to pamidronate highlights its potential as a therapeutic agent for bone health, supporting its utility in bone metabolism. MMT peel powder augments cell proliferation and induces beneficial morphological. Keywords: Melon Manis Terengganu (MMT) peel powder, hFOB 1.19 cell line, MTT assay 120 1 2 3 1* 1 2 3
Presenter’s ID: PD13 Category: Natural Products LARVICIDAL BIOEFFICACY OF THE METHANOLIC EXTRACTS FROM FRUIT WASTES OF Citrullus lanatus RINDS AND Lansium domesticum PEELS AGAINST Aedes spp. LARVAE Chun Zhong Phang, Lai yee Ho Department of Allied Health Sciences, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia. *Corresponding author email address: [email protected], [email protected] Mosquito-borne illnesses pose a significant health risk in developing countries. The frequent use of synthetic insecticides can lead to vector resistance, environmental pollution, ecosystem disturbance, and poisoning of non-target organisms. To address these issues, phytochemical substances derived from plant extracts are sourced as insecticide alternatives. This research studied the larvicidal bioefficacy of methanolic extracts from fruit wastes of Citrullus lanatus rinds and Lansium domesticum peels against larvae of Aedes aegypti and Aedes albopictus, including changes in their morphology. The concentrations of each methanolic extract at 3,125 ppm, 6,250 ppm, 12,500 ppm, 25,000 ppm, 50,000 ppm, and 100,000 ppm were evaluated against third instar Aedes spp. larvae in the larvicidal bioassay. Both methanolic extracts showed significant larvicidal effects against Aedes spp. larvae, which were dose- and time-dependent. Methanolic extract of Citrullus lanatus rinds had lower LC50 and LC95 values against Aedes spp. larvae at both 24 hours (Aedes aegypti: 9,330.08 ppm and 23,478.03 ppm; Aedes albopictus: 8,447.81 ppm and 31,100.32 ppm) and 48 hours of post-treatment (Aedes aegypti: 4,815.79 ppm and 12,106.71 ppm; Aedes albopictus: 5,707.17 ppm and 25,464.94 ppm) compared to Lansium domesticum peels at both 24 hours (Aedes aegypti: 15,101.13 ppm and 38,830.56 ppm; Aedes albopictus: 15,165.66 ppm and 42,460.39 ppm) and 48 hours of post-treatment (Aedes aegypti: 9,202.88 ppm and 29,547.75 ppm; Aedes albopictus: 10,020.93 ppm and 29,561.40 ppm). It was believed that the morphological changes observed in the third instar larvae of Aedes spp. following treatment, where the body becomes distorted and swollen with a darker midgut and an extended cephalo-thoracic junction, are due to the effects of phytochemical compounds in plant extracts that disrupt the larvae's physiological state and mechanisms. This study demonstrated that the methanolic extracts of Citrullus lanatus rinds and Lansium domesticum peels have significant larvicidal activities, making them potential alternatives for vector control. Keywords: Solvent extraction, larvicidal, medical entomology 121
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