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In Malaysia, Piper sarmentosum or 'kaduk' is commonly used in traditional medicines. However, its biological effects including in vivo embryonic toxicity and tissue regenerative properties are relatively unknown. The purpose of this study was to determine zebrafish (Danio rerio) embryo toxicities and caudal fin tissue regeneration in the presence of P. sarmentosum aqueous extracts. The phytochemical components and antioxidant activity of the extract were studied using GC-MS analysis and DPPH assay, respectively. Embryo toxicity tests involving survival, heartbeat, and morphological analyses were conducted to determine P. sarmentosum extract toxicity (0-60 µg/mL); concentrations of 0-400 µg/mL of the extract were used to study tissue regeneration in the zebrafish caudal fin. The extract contained several phytochemicals with antioxidant activity and exhibited DPPH scavenging activity (IC 50 = 50.56 mg/mL). Embryo toxicity assays showed that a concentration of 60 μg/mL showed the highest rates of lethality regardless of exposure time. Slower embryogenesis was observed at 40 µg/mL, with non-viable embryos first detected at 50 µg/mL. Extracts showed significant differences (p < 0.01) for tissue regeneration at all concentrations when compared to non-treated samples. In conclusion, Piper sarmentosum extracts accelerated tissue regeneration, and extract concentrations at 60 µg/mL showed the highest toxicity levels for embryo viability. Natural products have been frequently used as dietary supplements for health promotion and for culinary uses due to their herbaceous scents and flavours. Piper sarmentosum is one particular natural product with several medicinal effects including anti-cancer and fracture healing properties 1, 2. P. sarmentosum is a medicinal plant found in tropical countries, such as Indonesia, the Philippines, and Malaysia. The plant is widely consumed in the Asean region for its medicinal benefits. Aqueous extracts from P. sarmentosum have been found to produce anti-cancer effects on human liver cancer and Chang's cell lines 2, 3. However, further study on Chang's cell lines which originally derived from normal liver has found this cell is indistinguishable from HeLa (human cervical cancer) by STR PCR 4. P. sarmentosum extracts have been reported to produce aid in healing fractures; such extracts contain flavonoid compounds that reduce bone loss and increase bone strength in ovariectomised rats 1 .

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Dengue virus (DENV) is a globally significant human pathogen that annually infects more than $300 million of the Earth's population. While the clinically approved anti-dengue vaccine, Dengvaxia is available for treating such infection, its treatment is limited to those infected with DENV of serotypes 3 and 4 only. However, the vaccine is no longer available to treat dengue infections following the suspended use of Dengvaxia after several discoveries on the side effects of the vaccine on humans. In view of this recent development, a collection of plant extracts in the MyNature50000 library showing potential anti-dengue activities were explored. In this work, the DENV2 NS2B-NS3 bioassay was setup and optimized to evaluate the potential inhibitory activity of plant extracts stored in the MyNature50000 natural product collections. A total of 150 plants were examined using the high-throughput screening assay, among which four candidate plants showed potential as inhibitors of the DENV2 NS2B-NS3 protease, with exceptional inhibition activity >95% with corresponding IC 50 values ranging within 2 À 5 mg/mL. Two local plants, Syzygium campanulatum ('Kelat Paya') and Syzygium grande ('Keriang Batu'), were phytochemically analyzed and the data revealed existence of cyclododecane, n-hexadecanoic acid and caryophyllene, all of which are compounds well-known for their inhibitory activity against DENV2 NS2B-NS3. Additionally, MTT assays showed that both plants were mildly cytotoxic on mammalian cell lines, with IC 50 values >20 mg/mL, indicating their prospective use as drugs to combat DENV.

Aim: This paper reviews the different in vitro models of human intestinal epithelium that have been utilized for studying the adhesion and invasion properties. Problem Statement: The cell adhesion and invasion are the key mechanisms of bacterial pathogenicity that determines their possible routes of transmission. Numerous investigations related to the adhesion and invasion ability of bacterial isolates have been reported on monoculture human intestinal cells. However, the use of monoculture cells has several major disadvantages, such as the inability to reproduce the complex structure that defines the intestine and the inability to accurately predict the mechanism of bacterial adhesion and invasion. Approach: Co-culture models of human intestine have been developed as an alternative to improve the monoculture epithelial cell for adhesion and invasion studies, which provide more flexibility and overcome some of the limitations Conclusion: With the use of diverse in vitro approach, it could provide thorough information on different ability of bacterial adhesion and invasion and it could help to clarify the intricacy of host-pathogen interactions that underpin bacterial pathogenesis.

Despite advancement in food analytical platforms and availability of CODEX standard, the fraud honey relentlessly remains as global issue. Even with stringent guidelines, controlling the incoming honey product at ground level proved to be challenging and difficult to tackle. While most analytical platforms are powerful enough to detect counterfeit honey products, there is also a need to develop a rapid screening test to support field regulatory activity. A chemical reagent developed based on biochemistry principle has proved to be able to differentiate synthetic honey product from its raw counterpart. The reaction required only three drops of honey product to react with few drops of reagent mixtures which resulted in a change of color and precipitation of proteins and other molecules within 2 min reaction. Test performed on raw honey samples inclusive of several stingless bees and Apis species honey resulted in a precipitation as compared to fake honey generated from a blend of white sugar, golden syrup, vinegar, lime juice and plantain which resulted in clear organic phase indicating missing natural honey biological matters. The difference between raw honey and fake honey reaction with the reagents can be utilized for real time on field screening activity before proceeding with authentication using complex analytical platforms.