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Syairah Liyana Mohd Abd Ghafar,1 Mohd Zobir Hussein,2 Yaya Rukayadi,1,3 Md Zuki Abu Bakar Zakaria1,4 1Institute of Bioscience, 2Institute of Advance Technology, 3Department of Food Science, Faculty of Food Science and Technology, 4Department of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Calcium carbonate aragonite polymorph nanoparticles derived from cockle shells were prepared using surface functionalization method followed by purification steps. Size, morphology, and surface properties of the nanoparticles were characterized using transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, zetasizer, X-ray powder diffraction, and Fourier transform infrared spectrometry techniques. The potential of surface-functionalized calcium carbonate aragonite polymorph nanoparticle as a drug-delivery agent were assessed through in vitro drug-loading test and drug-release test. Transmission electron microscopy, field emission scanning electron microscopy, and particle size distribution analyses revealed that size, morphology, and surface characterization had been improved after surface functionalization process. Zeta potential of the nanoparticles was found to be increased, thereby demonstrating better dispersion among the nanoparticles. Purification techniques showed a further improvement in the overall distribution of nanoparticles toward more refined size ranges

Lamin Saidykhan,1 Md Zuki Bin Abu Bakar,2 Yaya Rukayadi,1,3 Aminu Umar Kura,4 Saiful Yazan Latifah5 1Microbiology Unit, Laboratory of Natural Products, Institute of Bioscience, 2Laboratory of Anatomy and Histology, Department of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, 3Department of Food Science, Faculty of Food Science and Technology, 4Vaccine and Immunotherapeutics Laboratory Unit, Institute of Bioscience, 5Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia Abstract: A local antibiotic delivery system (LADS) with biodegradable drug vehicles is recognized as the most effective therapeutic approach for the treatment of osteomyelitis. However, the design of a biodegradable LADS with high therapeutic efficacy is too costly and demanding. In this research, a low-cost, facile method was used to design vancomycin-loaded aragonite nanoparticles (VANPs) with the aim of understanding its potency in developing a nanoantibiotic bone implant for the treatment of osteomyelitis. The aragonite nanoparticles (ANPs) were synthesized from cockle shells by a hydrothermal approach using a zwitterionic surfactant. VANPs were prepared using antibiotic ratios of several nanoparticles, and the formulation (1:4) with the highest drug-loading efficiency (54.05%) was used for physicochemical, in vitro drug release, and biological evaluation. Physiochemical characterization of VANP was performed by using transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, and Zetasizer. No significant differences were observed between VANP and ANP in terms of size and morphology as both samples were cubic shaped with sizes of approximately 35 nm. The Fourier transform infrared spectroscopy of VANP indicated a weak noncovalent interaction between ANP and vancomycin, while the zeta potential values were slightly increased from -19.4±3.3 to -21.2±5.7 mV after vancomycin loading. VANP displayed 120 hours (5 days) release profile of vancomycin that exhibited high antibacterial effect against methicillin-resistant Staphylococcus aureus ATCC 29213. The cell proliferation assay showed 80% cell viability of human fetal osteoblast cell line 1.19 treated with the highest concentration of VANP (250 µg/mL), indicating good biocompatibility of VANP. In summary, VANP is a potential formulation for the development of an LADS against osteomyelitis with optimal antibacterial efficacy, good bone resorbability, and biocompatibility. Keywords: cockle shell-derived nanoparticles, nanoantibiotics, in vitro drug release, antibacterial activity, biocompatibility

Bacterial growth in food sources after harvesting and during food manufacturing has emerged as a major agricultural concern. Currently, several chemical preservatives have been added to foods to prevent or inhibit bacterial growth. These phenomena, however, become a concern when consumers begin to demand the safety of the food they consume, thus resulting in a search for natural plant extracts as an alternative. The antimicrobial activity of Cosmos caudatus leaf extract against six food pathogens was thus investigated in the present work. The disc-diffusion test, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) tests were used to determine the antibacterial potential. Time-kill kinetics were used to determine their killing endpoints at various incubation times. Thereafter, Bacillus cereus was selected as a representative bacterium to be viewed under the light sheet electron microscope (LSEM) to observe the morphological changes. For the application as a sanitiser, different concentrations of C. caudatus extract were applied to chicken meat and oyster mushroom to determine bacterial reduction and sensory acceptability. The toxicity test using brine shrimp lethality assay was also performed to determine the toxicity level of C. caudatus extract. Results showed that C. caudatus extract contain five major peaks of flavonoids. In the antibacterial test, all tested pathogens were inhibited, with B. cereus being the most susceptible, with a significant reduction time of more than 3 log10 at 3.125 mg/mL. Under LSEM, the population of B. cereus was reduced, and the shape was wrinkled. In the application, C. caudatus extract at 0.05% for 5 min treatment time was chosen as the best formulation, whereas the brine shrimp tests showed that C. caudatus extract was safe for human consumption (LC50: 3.54 mg/mL). In conclusion, C. caudatus extract could have the potential to be further explored as a natural food sanitiser. [ABSTRACT FROM AUTHOR]

Growing population in Malaysia has resulted in increased production of local vegetables as well as pesticide usage. This constitutes a health risk to human health. In the present work, the level of ten pesticide residues namely chlorpyrifos, profenofos, aldrin, endrin, cypermethrin, lambda-cyhalothrin, carbendazim, propamocarb, imidacloprid, and thiamethoxam in ten types of vegetables collected from six local markets were measured using modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Results showed that 13.3% samples contained pesticide residues above the maximum residue limit (MRL) prescribed by the Malaysian Food Regulations 1985, 55.0% of samples contained pesticide residues below the MRL, and no pesticide residues were detected in 31.7% of samples. Carbendazim and chlorpyrifos were among the highest pesticides detected in the samples. For the type of vegetables, kale and spinach contained high concentrations of pesticide residues above the MRL. In order to produce safe vegetables, the efficiency of different washing methods (tap water, 10% sodium bicarbonate solution, and 10% acetic acid solution) in reducing carbendazim and chlorpyrifos residues in a kale model system was evaluated. Results showed that the levels of carbendazim and chlorpyrifos reduction for all three methods were significantly different (p < 0.05) with 10% acetic acid solution being the most effective followed by 10% sodium bicarbonate solution, and tap water. Washing kale with 10% acetic acid reduced 76.0 and 41.2% of carbendazim and chlorpyrifos, respectively. Therefore, it is recommended for consumers to practice 10% sodium bicarbonate washing method by soaking vegetables with an acidic solution followed by rinsing with tap water to reduce pesticide residues, and minimise the exposure to hazardous pesticides. [ABSTRACT FROM AUTHOR]

The present work evaluated the antimicrobial potential of the ethanolic extract of jambu mawar [Syzygium jambos (L.) Alston] leaves against various foodborne pathogens and spoilage microorganisms via the disc diffusion assay (DDS) and the time-kill curve assay. These microorganisms included bacteria (Klebsiella pneumoniae ATCC13773, Listeria monocytogenes ATCC19112, Proteus mirabilis ATCC21100, Pseudomonas aeruginosa ATCC9027, Staphylococcus aureus ATCC29737, and Vibrio parahaemolyticus ATCC17802), yeasts (Candida albicans ATCC10231, C. krusei ATCC32196, C. glabrata ATCC2001, and C. parapsilosis ATCC22019), and moulds (Aspergillus fumigatus ATCC26430, A. niger ATCC9029, Rhizopus oligosporus ATCC22959, and R. oryzae ATCC22580). The inhibition zone of DDA ranged from 7.00 ± 0.23 to 10.25 ± 0.29 mm. The minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal (MBC/MFC) of the ethanolic leaf extract were obtained at the concentrations of 0.01 to 2.50 and 0.01 to 5.00 mg/mL, respectively. The time-kill curve assay showed that except for P. mirabilis, other microorganisms were completely killed at MIC concentrations ranging from 0.5 to 4× MIC. In comparison, P. mirabilis showed a growth reduction of > 3 log10 CFU/mL for 4 h. Meanwhile, the conidial germination of A. fumigatus was fully inhibited at 0.5× MIC. Though not fully inhibited, the ethanolic leaf extract significantly reduced the conidial germination of A. niger, R. oryzae, and R. oligosporus to 7.0, 7.0, and 11.0%, respectively. Overall, the ethanolic leaf extract of S. jambos exhibited antimicrobial activity against foodborne pathogens and spoilage microorganisms. [ABSTRACT FROM AUTHOR]

Cantaloupe is an excellent source of carotenoids, phenolics, flavonoids, carbohydrates, and minerals. Fresh cantaloupe is a seasonal fruit, highly perishable, and has a short shelf life. In the present work, the physicochemical properties of spray-dried cantaloupe powder with various Arabic gum (AG) concentrations (5 - 15%), and its food application in cake icing were evaluated. Results showed that spray-dried cantaloupe powder with 10% AG exhibited the best quality in terms of moisture content, hygroscopicity, hue, water solubility index, and total carotenoid content. A rheological test was then conducted on the cake icing incorporated with spray-dried cantaloupe powder with 10% AG at a powder-to-icing ratio of 1:10, and in temperature between 15 and 35°C. Steady shear flow of cake icing incorporated with spray-dried cantaloupe powder fit the Power Law model. The flow behaviour index of the icing was 0.134, and showed no significant difference (p < 0.05) with the control sample. The cake icing incorporated with spray-dried cantaloupe powder showed higher b* value (yellowness) as compared to the control sample. This indicated that spray-dried cantaloupe powder with 10% AG has the potential to produce cake icing with a natural colorant and high in antioxidants, with no significant effect on the flow behaviour index of the produced cake icing. [ABSTRACT FROM AUTHOR]

Recently, there has been an increasing demand and interest in developing plant extracts as natural food sanitizer, owing to their antimicrobial properties. Hence, the aim of this study was to investigate the effect of salam (Syzygium polyanthum L.) leaves methanolics extract on the number of microflora on chicken meat and shrimp. Salam leaves extract at different concentrations (0.0%, 0.1%, 1.00%) and exposure times (5, and 10 min) used to treat chicken meat and shrimp by using dilution method. Result showed that the total plate count and Staphylococcus aureus had been detected in untreated chicken and shrimp samples with 6.66 ± 0.12, 8.66 ± 0.15 and 7.25 ± 0.21, 6.54 ± 0.21, respectively. However, there was no Escherichia coli, Salmonella spp. and Vibrio cholerae detected in both samples. The number of total plate count (TPC) and S. aureus in chicken meat and shrimp were starting to reduce significantly at 0.01% concentration of salam leaves extract for 5 minutes of exposure time compared to initial count. There was no significantly different between exposure times. The highest reduction in number of microorganism population was at treatment with 1.0% extract for 10 min where TPC was reduced from 6.66 ± 0.12 to 0.00 ± 0.00 log CFU/ml, and from 8.66 ± 0.15 to 4.88 ± 0.00 log CFU/ml in shrimp while S. aureus reduced from 7.25 ± 0.21 to 3.88 ± 0.01 and from 6.54 ± 0.21 to 4.92 ± 0.04 in chicken and shrimp, respectively. For the sensory acceptability, overall acceptability were accepted by panellists until treatment 0.10% for 5 min and 10 min of soaking time. In conclusion, salam leaves extract might be developed as natural sanitizer for rinsing raw food materials such as chicken meat and shrimp. [ABSTRACT FROM AUTHOR]

The filamentous spoilage fungi in vegetables can lead to significant impact in food and economic loss. In order to overcome this problem, chemical fungicide has been implemented in vegetable farming and processing but it causes problems towards environment and food safety. Thus, the utilization of natural products such as plants extracts, which exhibit antimicrobial and antifungal activity, is more acceptable to solve this problem. The aim of this study is to investigate the antifungal activity of Boesenbergia rotunda extract against ten filamentous spoilage fungi isolated from five vegetables. The extract was used to treat fungal isolates from vegetables; CRb 002 (Penicillium sp.), CHa 009 (Aspergillus sp.), TMa 001 (Geotrichum sp.), TMa 002 (Aspergillus sp), ONb 001 (Aspergillus sp.), WBb 003 and WBb 004 (Fusarium sp.) WBb 007 (unidentified), WBb 008 (Aureobasidium sp.) and WBb 010 (Penicillium sp.). The results showed that the yield of the extract of B. rotunda using ethanol (95%) was 11.42% (w/v). The 10% of B. rotunda extract exhibited antifungal activities against ten filamentous fungi after 5 days treatment with growth reduction of 41.56%, 30.68%, 86.20%, 50.62%, 26.67%, 47.44%, 50.74%, 36.39%, 42.86%, and 39.39% for WBb 008, WBb 004, WBb 007, WBb 003, CRb 002, WBb 010, CHa 009, TMa 001, ONb 001, and TMa 002, respectively. B. rotunda extract showed highest antifungal activity against fungi isolated from winged bean (WBb 007) with percentage reduction in growth was 86.20%, while the lowest activity was against fungi isolated from the carrot (CRb 002) with 26.67% reduction in growth. Generally, the TPC of fungi in the vegetable samples were reduced after treatment with 5% of B. rotunda extract at 5 min and 10 min of exposure time. The results suggested that B. rotunda extract has high potential to become natural food preservative which can reduce the fungi spoilage of vegetables. [ABSTRACT FROM AUTHOR]

Plants have been used recently to eliminate bacterial growth in food products. This study was undertaken to test the in vitro sanitizing effect of crude extract from bitter gourd (BG) fruit on the growth of native microorganisms in raw chicken leg meat. Hot air dried BG and extrudate extracts at 1% concentration and exposure times of (5, 10 and 15 min) were used to treat the samples using dilution method. Results showed that BG extrudate had a slightly stronger bactericidal activity against the microflora than the B.G. hot air drying treatment, especially, on E. coli at all exposure time. Overall, there is no significant difference between the treatments; Total Plate Count (TPC), Escherichia coli, Bacillus cereus, Staphylococcus aureus. The best reduction time of microflora by hot air dried extract was at (15 min) except for B. cereus was at (5 min) and for extrudate extract was at (5 min) except for E. coli was at (10 min). In conclusion, bitter gourd extract could be used as an important natural sanitizer for rinsing raw food matrials such chicken meat. [ABSTRACT FROM AUTHOR]

Listeriosis and salmonellosis are the major foodborne illnesses worldwide. Over the last decade, increasing reports about the antibiotic resistance of Listeria monocytogenes and Salmonella from diverse sources have prompted public health concerns, especially in developing countries with over reliance or misuse of antibiotic drugs in the treatment of humans and animals. In this study, antibiotic susceptibility profiles of 58 L. monocytogenes and 12 Salmonella Enteritidis strains from vegetable farms and retail markets in Malaysia were testedby the standard disk diffusion method. Listeria monocytogenes isolates were found to exhibit 100% resistance to penicillin G. Also, high resistance patterns were observed for meropenem (70.7%) and rifampicin (41.4%). The multiple antibiotic resistance (MAR) index of L. monocytogenes isolates ranged from 0.11 to 0.56. Besides, the antibiogram results revealed that multidrugresistant (MDR) S. Enteritidis were detected and all the S. Enteritidis isolates demonstrated resistance to at least four antibiotics. Ampicillin, amoxicillin, and trimethoprim failed to inhibit all the S. Enteritidis strains. Salmonella Enteritidis isolates also displayed high resistance to nalidixic acid (75.0%), trimethoprim-sulfamethoxazole (75.0%), and chloramphenicol (66.7%). Findings in this study indicated that vegetables could be potential sources of multidrug resistance of L. monocytogenes and S. Enteritidis, which can be a serious issue and a major concern for public health. Thus, there is a great need for surveillance programs in Malaysia to continuously monitor the antibiotic resistance profiles of important pathogens. [ABSTRACT FROM AUTHOR]

Increase of foodborne diseases has promulgated the development of new natural food additive with high extraction yield to eliminate food pathogenic organisms. One such possibility is the use of plant product as antibacterial agents with non-conventional method to enhance the yield. In this study, cinnamon leaves (Cinnamomum zeylanicum Blume) were subjected to ultrasonic assisted extraction (UAE) using response surface methodology (RSM) to optimise extraction yield and total phenolic contents. The effect of two independent factors, extraction temperature (x1: 25-40°C) and extraction time (x2: 15-45 minutes) were investigated. Optimum extraction yield and total phenolic contents of cinnamon leaves were 27.49 ± 1.59% and 3987 ± 79.10 mg GAE/g which were closely as predicted using RSM (28.34%, 4048 mg GAE/g), respectively. The optimum condition of extraction yield (40°C and 45 minutes) showed the maximum zone of inhibition against all tested foodborne pathogens (7.33 ± 0.50 to 13.22 ± 0.44 mm), whereas optimum condition of total phenolic contents (33°C and 31 minutes) showed the lowest zone inhibition (6.78 ± 0.67 mm to 11.67 ± 1.41 mm). The minimal inhibitory concentration (MIC) values range from 97.65 to 6250.00 μg/mL and minimal bactericidal concentration (MBC) values from 6.25 to 50.00 mg/mL. These results indicated that UAE method is excellent in producing significantly the highest of extraction yield, total phenolic contents and act as a potential natural antibacterial agent even using low extraction temperature and short time. [ABSTRACT FROM AUTHOR]