Judul: Effect of cajuputs candy formulas on competitive capacity of streptococcus sanguinis upon streptococcus mutans in multispecies biofilm.
Abstrak: Cajuputs candy development as a functional food has been shifted to maintain the oral health. Cajuputs candy is classified as hard candy which utilized cajuput and peppermint oil as its flavor components. Streptococcus sanguinis is a health-associated species which can control the growth of cariogenic species, S. mutans. These two oral Streptococci have antagonistic interaction which plays a role in preventing dental caries formation. The aim of this research is to determine the effects of two type of cajuputs candy, i.e. Sucrose Cajuputs Candy (SCC) and Non-Sucrose Cajuputs Candy (NSCC), on competitive capacity of S. sanguinis upon S. mutans in multispecies (S. sanguinis+S. mutans) biofilm, which is indicated by its ability to form biofilm, control the growth of S. mutans, and expressed spxB mRNA. The spxB mRNA expression reflected hydrogen peroxide (H2O2) production by S. sanguinis. Volatile constituents of cajuputs candy’s flavors were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). In vitro biofilm assay with optical density (OD) measurement was used to examine the potency of cajuputs candy in inhibiting the formation of multispecies biofilm. Quantitative real-time polymerase chain reaction (real-time PCR) techniques were applied for quantification of spxB mRNA and relative amount of total DNA bacterium in the biofilms. Several reported antimicrobial components, i.e. 1,8-cineole (23,67%), α-terpineol (9,17%), menthol (7,29%), β-caryophyllene (6,78%), menthone (3,30%), and terpinen-4-ol (1,86%) were detected in SCC. Meanwhile, the reported antimicrobial components, i.e. menthol (13,32%), α-terpineol (9,97%), 1,8-cineole (8,48%), β-caryophyllene (7,64%), menthone (4,43%) and terpinen-4-ol (1,28%) were also detected in NSCC. The biofilm assay showed that the exposures of SSC and NSCC were effective in inhibiting multispecies biofilm. Biofilm inhibition caused by SCC was 59,2% and NSCC was 68,2%. Moreover, SCC and NSCC exposures also decreased the relative amount of total DNA in multispecies biofilm to be 1,20% and 1,04% compared to the control (100%), respectively. These reductions were indicating that SCC and NSCC could inhibit biofilm formation of S. sanguinis and S. mutans, in vitro. Exposures of candy formula without flavor, i.e sucrose candy without flavor and non-sucrose candy without flavor, also affected biofilm formation. The ability to form biofilm affected by sucrose candy and non-sucrose candy without flavor exposures were decreased 36,9% and 47,1% compared with the control, respectively. However, sucrose candy and non-sucrose candy without flavor exposures were induced bacterial growth with percentage of total DNA in the biofilm were 184,77% and 221,29% increase compared with the control, respectively. It seems that utilization of sucrose without addition of antibacterial component, e.g. essential oil as flavoring agent, could induce bacterial growth. Even a non-sucrose utilization, in this study is isomalt - a non-cariogenic polyol-, with a long exposure time (approx. 20 hours) in this research could be fermented by these Streptococci and can be used for their growth. This indicated that cajuput and peppermint oil in SCC and NSCC showed antibacterial activity. The proportion of S. sanguinis DNA in multispecies biofilms was lower than S. mutans DNA in all samples, which ranged from 35 to 42% for S. sanguinis and 58 to 65% for S. mutans. This bacterial DNA proportion was not statistically significant compared with
Keyword: cajuputs candy, biofilm inhibition, Streptococcus sanguinis, Streptococcus mutans, spxB mRNA

Judul: Potensi Cajuputs Candy Non Sukrosa sebagai Penghambat Aktivitas Streptococcus mutans dalam Pembentukan Biofilm
Abstrak: Cajuputs candy is a confectionery considered as functional product effective for throat lozenges. Flavor compounds of cajuputs candy has been reported as inhibitor of biofilm formation by S. mutans serotype C. Non sucrose cajuputs candy is a product of cajuputs candy developed by replacing sucrose as the main component by isomalt. The aim of this research is to observe the potency of non sucrose cajuputs candy to inhibit the activity of S. mutans in biofilm formation by identifying the volatil components of candy and monitoring the formation of biofilm. This study has three experiment models. Control model (K) is non sucrose candy without flavor compounds, CC1 model is cajuput candy non sucrose with cajuput extract as flavor compound, and CC2 model is cajuputs candy non sucrose with cajuput and peppermint extract as flavor compounds. The volatil components was identified using Gas Chromatography Mass Spectra (GC-MS) with capillary column DB-5 MS in flavor laboratory of Indonesia Rice Research Center, Sukamandi-Subang, West Java. The volatil components of cajuput and peppermint extract is used as former information that could verify volatil components in CC1 and CC2. The inhibition of S. mutans activity in biofilm formation was monitored by analysis of biofilm mass viability and quantification of gtfB-gtfC mRNA with 4 and 6 hours incubation time. The viability of biofilm mass analysis and mRNA quantification was conducted in biology oral laboratory of Dentistry Faculty-University of Indonesia. The viability of biofilm mass obtained by monitoring the absorbance of biofilm suspension using microplate Enzyme Linked Immunosorbent Assay (ELISA) Reader. Expression level of gtfB-gtfC mRNA obtained by monitoring the CT The identification result of volatil components based by LRI value showed that cajuput extract has 22 volatil components inside meanwhile peppermint extract has 17 volatil compponents inside. The main volatil components of cajuput extract, consecutively are 1,8-cineole (47,61%), α-terpineol (10,76%), α-caryophyillene (7,91%), γ-terpinene (5,78%), terpinyl acetate (4,09%), α-pinene (3,90%), p-cymene (3,75%), and terpinolene (3,52%). The main volatil components of peppermint extract, consecutively are menthol (32,53%), menthon (15,60%), isomenthon (11,87%), methyl salicylate (10,86%), D-limonene (10,07%), β-pinene (3,77%), dan α-pinene (3,09%). The volatil components of cajuput and peppermint extract becoming components target of CC1 and CC2. The study showed that CC1 has 14 volatil components with main volatil components consecutively are 1,8-cineole (39,26%), α-terpineol (19,63%), dan α-caryophyillene (17,90%). Meanwhile CC2 has 18 volatil components with main volatil components consecutively are menthol (23,47%), α-terpineol (17,57%), value of gtfB and gtfC mRNA during amplification process using Real Polymerase Chain Reaction (RT-PCR). 1,8-cineole (14,94%), α-caryophyllene (13,46%), menthone (7,80%), dan isomenthone (7,65%). This research showed that the optimum inhibition of biofilm mass formation occured in 4 hours incubation with inhibition potency of K, CC1, and CC2 consecutively are 63,98%, 48,34%, and 65,64%. The inhibition potency of all models are less than 50% in 6 hours incubation, only CC2 has inhibition potency more than 40%. The expression level of gtfB mRNA in K, CC1, and CC2 model is higher than blank during 4 hours incubation. The experiment models K, CC1, and CC2 could inhibit the expression of gtfB mRNA later (6 hours incubation). Meanwhile, the existence
Keyword: 

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: