Biofilms are increasingly recognized as playing a major role in human infectious diseases, as they can form on both living tissues and abiotic surfaces, with serious implications for applications that rely on prolonged exposure to the body such as implantable biomedical devices or catheters. Therefore, there is an urgent need to develop improved therapeutics to effectively eradicate unwanted biofilms. Recently, the biological signaling molecule nitric oxide (NO) was identified as a key regulator of dispersal events in biofilms. In this paper, we report a new class of core cross-linked star polymers designed to store and release nitric oxide, in a controlled way, for the dispersion of biofilms. First, core cross-linked star polymers were prepared by reversible addition-fragmentation chain transfer polymerization (RAFT) via an arm first approach. Poly(oligoethylene methoxy acrylate) chains were synthesized by RAFT polymerization, and then chain extended in the presence of 2-vinyl-4,4-dimethyl-5-oxazolone monomer (VDM) with N,N-methylenebis(acrylamide) employed as a cross-linker to yield functional core cross-linked star polymers. Spermine was successfully attached to the star core by reaction with VDM. Finally, the secondary amine groups were reacted with NO gas to yield NO-core cross-linked star polymers. The core cross-linked star polymers were found to release NO in a controlled, slow delivery in bacterial cultures showing great efficacy in preventing both cell attachment and biofilm formation in Pseudomonas aeruginosa over time via a nontoxic mechanism, confining bacterial growth to the suspended liquid.

Proses menua merupakan proses yang alamiah dimana terjadi berbagai perubahan pada seluruh sistem tubuh lansia, termasuk sistem kardiovaskuler yang biasanya diikuti oleh penyakit utama yakni hipertensi. Penelitian ini bertujuan untuk mengetahui faktor-faktor yang berhubungan dengan hipertensi pada lansia diatas Umur 65 tahun. Pengambilan data dilakukan pada 87 orang responden yang merupakan lansia di atas umur 65 tahun secara total sampling, dengan alternatif uji Fisher pada faktor keturunan dan obesitas. Hasil uji menunjukkan adanya hubungan antara faktor keturunan dengan hipertensi Pvalue ≤ 0,05, tidak ada hubungan antara faktor jenis kelamin, obesitas, kebiasaan merokok, stres, olahraga dengan Pvalue > 0,05. Disarankan kepada lansia diatas 65 tahun yang menderita hipertensi untuk melakukan pengontrolan tekanan darah secara rutin dan disarankan kepada petugas kesehatan untuk melakukan promosi kesehatan atau pencegahan hipertensi terkait lansia.

The isolation of crystalline regions from fibers cellulose via the hydrolysis route generally requires corrosive chemicals, high-energy demands, and long reaction times, resulting in high economic costs and environmental impact. From this basis, this work seeks to develop environment-friendly processes for the production of Bacterial Cellulose Nanocrystals (BC-NC). To overcome the aforementioned issues, this study proposes a fast, highly-efficient and eco-friendly method for the isolation of cellulose nanocrystals from Bacterial Cellulose, BC. A two-step processes is considered: (1) partial depolymerization of Bacterial Cellulose (DP-BC) under ultrasonic conditions; (2) extraction of crystalline regions (BC-NC) by treatment with diluted HCl catalyzed by metal chlorides (MnCl2 and FeCl3.6H2O) under microwave irradiation. The effect of ultrasonic time and reactant and catalyst concentrations on the index crystallinity (CrI), chemical structure, thermal properties, and surface morphology of DP-BC and BC-NC were evaluated. The results indicated that the ultrasonic treatment induced depolymerization of BC characterized by an increase of the CrI. The microwave assisted by MnCl2-catalyzed mild acid hydrolysis enhanced the removal of the amorphous regions, yielding BC-NC. A chemical structure analysis demonstrated that the chemical structures of DP-BC and BC-NC remained unchanged after the ultrasonic treatment and MnCl2-catalyzed acid hydrolysis process.

The framework of this work was to develop an emulsion-based edible film based on a chitosan nanoparticle matrix with cellulose nanocrystals (CNCs) as a stabilizer and reinforcement filler. The chitosan nanoparticles were synthesized based on ionic cross-linking with sodium tripolyphosphate and glycerol as a plasticizer. The emulsified film was prepared through a combination system of Pickering emulsification and water evaporation. The oil-in-water emulsion was prepared by dispersing beeswax into an aqueous colloidal suspension of chitosan nanoparticles using high-speed homogenizer at room temperature. Various properties were characterized, including surface morphology, stability, water vapor barrier, mechanical properties, compatibility, and thermal behaviour. Experimental results established that CNCs and glycerol improve the homogeneity and stability of the beeswax dispersed droplets in the emulsion system which promotes the water-resistant properties but deteriorates the film strength at the same time. When incorporating 2.5% w/w CNCs, the tensile strength of the composite film reached the maximum value, 74.9 MPa, which was 32.5% higher than that of the pure chitosan film, while the optimum one was at 62.5 MPa, and was obtained by the addition of 25% w/w beeswax. All film characterizations demonstrated that the interaction between CNCs and chitosan molecules improved their physical and thermal properties.

Abstract. Agustina S, Wiryawan KG, Suharti S, Meryandini A. 2021. The enrichment process and morphological identification of anaerobic fungi isolated from buffalo rumen. Biodiversitas 23: 469-477. Anaerobic fungi are one of the microbes that have an important role in rumen fiber degradation because they can produce cellulase enzymes and penetrate feed particles. Nevertheless, few studies were performed to test the potential of anaerobic fungi in Indonesia. Therefore, the present study was carried out to evaluate the impact of the enrichment process on pH value, the zoospores population, NH3 (ammonia) concentration, and VFA (Volatile Fatty Acid) proportion. In addition, this research was also performed to isolate anaerobic fungi from buffalo rumen and identify their morphological characteristics. The enrichment stage of anaerobic fungi was carried out using the Hungate method. Results showed that the population of fungi zoospores, pH value, ammonia concentration, the proportion of acetate, and total VFA were significantly affected by the incubation time (P<0.01). In addition, Caecomyces, Neocallimastix, and Piromyces were rumen anaerobic fungi isolated from buffalo rumen with different morphological characteristics. It can be concluded that the incubation time increased the zoospore population, the concentration of NH3, acetate proportion, and total VFA but decreased media's pH value.