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Rapid methods based on untargeted analysis technique such as Fourier Transform Infrared (FT-IR) spectroscopy can provide much faster and easier solution for food authentication. However, studies on the metabolite content in UKMR-2 calyces using FT-IR spectroscopy has not been reported yet in any previous studies. Thus, the present study was performed to analyze the differences in metabolite content in UKMR-2 calyces under the influences of different [CO2] treatment by applying tri-step infrared based fingerprinting. The UKMR-2 plant cultivation was exposed to ambient [CO2] (400 µmol/mol) and elevated [CO2] (800 µmol/mol) treatment. The UKMR-2 calyx extracts were analysed by conventional infrared (1D-IR), second derivative infrared (SD-IR) and two-dimensional correlation infrared (2D-IR) spectroscopy. The 1D-IR spectrum results revealed a similar absorption spectrum in the range of 1900 - 650 cm-1, which suggest similar major metabolites content present in both extracts. For SD-IR spectrum, both treatments clearly showed have more peaks with different shape, position and intensity in the range of 1650 - 1450 cm-1 and 1200 - 950 cm-1, which is likely to have different flavonoid and carbohydrate content in UKMR-2 calyces. The 2D-IR synchronous correlation spectrum in the range of 1000 – 650 cm-1 clearly distinguished the metabolite content in the UKMR-2 calyx extract from different [CO2] treatment. Therefore, this tri-step infrared based fingerprinting has the potential as one of the effective methods to discriminate extract samples with similar infrared fingerprint features and indicate that the metabolite content in UKMR-2 calyces were influenced by different [CO2] treatments.

The impact of global climate change on plants which has been widely reported can exhibit significant changes on the growth, yield and metabolite production. Studies on the impact of elevated carbon dioxide concentration, [CO 2 ] on plant growth and production of phenolic constituents in Hibiscus sabdariffa var. UKMR-2 has not been reported in any previous studies. This study investigated the growth quality and production of phenolic constituents of UKMR-2 under different [CO 2 ]. The cultivation was subjected to two atmospheric [CO 2 ]; ambient (400 µmol/mol), and elevated (800 µmol/mol). Selected parameters for growth performance were recorded throughout the plant development. UKMR-2 calyx extract was analysed for total phenolic, total anthocyanins, antioxidant activity, and evaluated based on HPLC-PDA method. The results revealed that UKMR-2 responded differently to the [CO 2 ] treatments. The results clearly showed that exposure to elevated [CO 2 ] increased calyx yields, production of phenolic constituents, and antioxidant activity. Furthermore, different [CO 2 ] had significant interaction on the production of phenolic constituents, and antioxidant activity (p < 0.05), except for plant growth. The HPLC-PDA showed the presence of delphinidin-3- O -sambubioside, cyanidin-3- O -sambubioside, ascorbic acid, caffeic acid, and chlorogenic acid. Therefore, increased [CO 2 ] may have significant effects on UKMR-2 to not only produce higher production yields, but also on the production of phenolic constituents with potential physiological impact to human health.

Marine actinomycetes are now in demand as they are capable of producing unique and novel compounds with wide biological activities. Marine Streptomyces sp. UKMCC_PT15 previously isolated from seawater collected in Pulau Tinggi, Johor was used in this study. Molecular identification showed high similarity of Streptomyces sp. UKMCC_PT15 with Streptomyces fradiae and S. diastaticus subsp. ardesiacus based on partial sequence of 16S rRNA gene. Further characterisations of this bacterium include spore morphology using SEM, growth on various media, salt tolerance test and carbon utilisation profile. This bacterium had straight spore chain with smooth-surfaced spores and was able to tolerate up to 11% NaCl with capabilities of utilising >40 carbon sources. Undecylprodigiosin (C 25 H 35 N 3 O) was successfully purified through succession of column chromatography and finally using HPLC. Structure elucidation was confirmed through NMR spectroscopy, MS and comparison with established data. This compound demonstrated strong antibacterial activities against S. aureus , B. subtilis and C. albicans but weak antibacterial activities against E. coli, P. aeruginosa and Methicillin-resistant S. aureus (MRSA), Interestingly, undecylprodigiosin also demonstrated algicidal activity when tested against toxic dinoflagellates, A. minutum and P. bahamense, both of which are responsible for harmful algal blooms (HABs) . Undecylprodiogiosin with concentration of 10-100 μg/ml gave ~100% algicidal activity against both dinoflagellates. Further testing with undecylprodigiosin concentration < 10 µg/ml showed that undecylprodigision was capable of killing significantly high numbers of both dinoflagellates, giving a high algicidal activity. Findings from this study suggested the potential use of undecylprodigiosin as algicidal agent which could be used for the mitigation of HABs

Phytochemical studies on the woods of Vatica pauciflora and Vatica lowii have been conducted. The woods of V. pauciflora were extracted with methanol by using Soxhlet apparatus while the woods of V. lowii were extracted with acetone at room temperature. The methanolic extract of V. pauciflora was semi-purified by using vacuum liquid chromatography (VLC) and further purified by high performance liquid chromatography (HPLC) to obtain a pure compound (1) . The same technique of semi-purification has been employed on V. lowii acetone extract which was further purified by radial chromatography to give a pure compound (2) . Based on the UV, IR, NMR and mass spectral data, the isolated compounds were characterized as (-)- cis -resveratrol-10- C -b-D-glucopyranoside and (-)-piceid respectively.

Streptomyces sp. has been known to produce antibiotics and other bioactive natural products. However, the production of these secondary metabolites depends on the culture conditions, where in most cases the secondary-metabolite genes are not expressed in fermentation culture. Recently, a novel fermentation method known as combined-culture has been introduced to unlock these “silent” genes, hence induces the production of cryptic metabolites. We report herein, our preliminary work on combined-culture using two soil-borne bacterial strains; Streptomyces and Tsukamurella. From the results, it is shown that the presence of Tsukamurella, a mycolic acid-containing bacterium induces the production of new metabolites in Streptomyces. Moreover, the production of compounds associated with Streptomyces was enhanced via combination-culture as compared to culture of Streptomyces strain alone. These findings may promote the feasibility of combined-culture in unlocking the “silent” genes of microorganisms which could lead to the discovery of novel metabolites.