Sesquiterpenoids and Xanthones from the Kiwifruit-Associated Fungus Bipolaris sp. and Their Anti-Pathogenic Microorganism Activity

Nine previously undescribed sesquiterpenoids, bipolarisorokins A–I (1–9); two new xanthones, bipolarithones A and B (10 and 11); two novel sativene-xanthone adducts, bipolarithones C and D (12 and 13); as well as five known compounds (14–18) were characterized from the kiwifruit-associated fungus Bipolaris sp. Their structures were elucidated by extensive spectroscopic methods, electronic circular dichroism (ECD), 13C NMR calculations, DP4+ probability analyses, and single crystal X-ray diffractions. Many compounds exhibited anti-pathogenic microorganism activity against the bacterium Pseudomonas syringae pv. actinidiae and four pathogenic microorganisms.

Microbial Pathogenesis

For a pathogenic microbe to cause disease in a susceptible host, it must gain access to that host first. The pathogenicity of a microbe is determined by the virulence factors alongside other innate mechanisms. Apart from the initiation of infection, these virulence factors also enable the pathogenic microorganism to survive in the new environment within the susceptible host. They also enable the pathogenic microorganism to invade the host, colonize, and evade the host defense mechanisms. These virulence factors include; invasins, capsules, siderophores, adhesins, enzymes, endotoxins, and exotoxins. Key words: Pathogenicity factors and Pathological effect on cells.

Research Progress on Antibiosis Activity of Scutellaria Flavonoids

Scutellariae (Huangqin) is a traditional medicine that is widely applied in China for the treatment of cold and fever, and nowadays research found that it can against pathogenic microorganism. Flavonoids is the main active constituent isolated from Scutellariae and possesses outstanding antibiosis activity. Scutellaria flavonoids displayed antiseptic actions and anti-resistance, including but not limited to destroy bacterial biofilm, suppressed activity of the DNA enzyme, restrain efflux pump and quorum-sensing system. This paper highlights and discusses the antibiosis activity of Scutellaria flavonoids, along with possible mechanisms of its action. hoping to providing basis and evidence for clinical application.

ANTIMICROBIAL STUDY OF PYROLIGNEOUS EXTRACT FROM RHIZOPHORA APICULATE AGAINST URINARY TRACT PATHOGENS

Various parts of the human body are host to certain microorganism species, such as fungi and bacteria which may cause urinary tract infections (UTIs). In this research, the pyroligneous extract as antimicrobial agent on urinary tract infection-related pathogenic microorganism were studied. The Time-kill kinetics assay was used to study an antimicrobial agent over time. A series of various concentration (0 – 24%) of the pyroligneous extract was tested. Each strain’s bioactivity was quantified after 60 minutes of incubation at 22.5 oC. From the result showed that pyroligneous extract reached 100% of reduction effects with different concentration (E.faecalis (19433) at 20%, E.coli (8739) at 4%, P.vulgaris (33420) at 4%), K.pneumoniae (13883) at 4%, C.albicans (10231) at 4%). For bioprocess kinetics analysis, the highest specific reduction rate and halve rate according concentration: E.faecalis at 24% (0.1426, 0.2058), E.coli at 4% (0.1219, 0.1759), P.vulgaris at 4% (0.1311, 0.1891), K.pneumoniae at 4% (0.1175, 0.1695), C.albicans at 4% (0.1175, 0.1695).These findings shows the importance of pyroligneous extract as antimicrobial agent, especially in urinary tract infection, as a natural antimicrobial agent in public health industries.

Metagenomic Next-Generation Sequencing Can Clinch Diagnosis of Non-Tuberculous Mycobacterial Infections: A Case Report

Non-tuberculou Mycobacteria (NTM) is ubiquitous in the environment and is conditional pathogen. Due to NTM and Mycobacterium tuberculosis belong to the genus Mycobacterium, their pathogenic mechanisms and clinical manifestations are similar. Therefore, NTM can cause tuberculosis-like lesions and lead to misdiagnosis. Early diagnosis and treatment greatly improve prognosis. However, traditional pathogenic microorganism detection has limitations, and it is difficult to accurately identify strains in clinical practice. Here, we report a 65-year-old man with NTM who presented with recurrent fever and cough. Computed tomography of the chest revealed a lung infection. The previous improper diagnosis and treatment did not improve his condition. With the aid of metagenomic next-generation sequencing, the pathogen was identified as Mycobacterium avium complex. Subsequently, he received accurate treatment and made significant improvements in clinical and radiology.

Identification of Amyloidogenic Regions in Pseudomonas aeruginosa Ribosomal S1 Protein

Bacterial S1 protein is a functionally important ribosomal protein. It is a part of the 30S ribosomal subunit and is also able to interact with mRNA and tmRNA. An important feature of the S1 protein family is a strong tendency towards aggregation. To study the amyloidogenic properties of S1, we isolated and purified the recombinant ribosomal S1 protein of Pseudomonas aeruginosa. Using the FoldAmyloid, Waltz, Pasta 2.0, and AGGRESCAN programs, amyloidogenic regions of the protein were predicted, which play a key role in its aggregation. The method of limited proteolysis in combination with high performance liquid chromatography and mass spectrometric analysis of the products, made it possible to identify regions of the S1 protein from P. aeruginosa that are protected from the action of proteinase K, trypsin, and chymotrypsin. Sequences of theoretically predicted and experimentally identified amyloidogenic regions were used to synthesize four peptides, three of which demonstrated the ability to form amyloid-like fibrils, as shown by electron microscopy and fluorescence spectroscopy. The identified amyloidogenic sites can further serve as a basis for the development of new antibacterial peptides against the pathogenic microorganism P. aeruginosa.

Pengaruh ekstrak daun kemangi (Ocimum basilicum L) terhadap Staphylococcus aureus di rongga mulutEffect of basil leaf extract (Ocimum basilicum L.) on oral Staphylococcus aureus

Pendahuluan: Staphylococcus aureus merupakan mikroorganisme dalam rongga mulut yang bersifat patogen. Di Indonesia, penyakit infeksi masih menjadi masalah umum terutama pada rongga mulut, untuk itu dikembangkan obat antibakteri yang berasal dari tumbuhan salah satunya daun kemangi. Tujuan penelitian untuk menganalisis efektivitas penggunaan ekstrak daun kemangi (Ocimum basilicum L) terhadap jumlah Staphylococcus aureus rongga mulut. Metode: Penelitian ini menggunakan true eksperiment laboratoris, dimana pengujian efektivitas antibakteri dengan metode pengenceran seri. Sampel yang digunakan strain murni Staphylococcus aureus dan isolat klinik Staphylococcus aureus. Konsentrasi ekstrak yang digunakan 50%, 25%, 12,5%, 6,25% dan dilakukan pengulangan sebanyak 4 kali. Data penelitian diolah menggunakan SPSS yaitu uji Kruskal-Wallis dan uji Mann-Whitney.Hasil: Konsentrasi 50% merupakan kadar bunuh minimum (KBM) untuk strain murni bakteri Staphylococcus aureus, dan kadar hambat minimum (KHM) untuk isolat klinik Staphylococcus aureus. Konsentrasi 25% hanya didapati kadar hambat minimum (KHM) untuk strain murni Staphylococcus aureus. Simpulan: Terdapat pengaruh penggunaan ekstrak daun kemangi (Ocimum basilicum L) terhadap penurunan jumlah Staphylococcus aureus rongga mulut.Kata kunci : Daun kemangi, Staphylococcus aureus, pengenceran seri, KHM, KBM. ABSTRACTIntroduction: Staphylococcus aureus is a pathogenic microorganism in the oral cavity. In Indonesia, infectious diseases are still a common problem, especially in the oral cavity. Therefore, a natural antibacterial remedy has been developed, one of which is basil leaves. The study aimed to analyse the effectiveness of using basil leaf extract (Ocimum basilicum L) against the number of oral Staphylococcus aureus. Methods: This study used a true laboratory experiment, where the antibacterial effectiveness was tested by using the series dilution method. The samples used were pure strains of Staphylococcus aureus and clinical isolates of Staphylococcus aureus. The extract concentration used was 50%, 25%, 12.5%, 6.25% and was repeated 4 times. The research data were processed using SPSS, namely the Kruskal-Wallis test and the Mann-Whitney test. Results: The concentration of 50% is the minimum kill rate (MKC) for pure strains of Staphylococcus aureus and the minimum inhibitory level (MIC) for clinical isolates of Staphylococcus aureus. At 25% concentration, only the minimum inhibitory level (MIC) was found for pure strains of Staphylococcus aureus. Conclusion: There is an effect of using basil leaf extract (Ocimum basilicum L) on reducing the number of oral Staphylococcus aureus.Keywords: Basil leaf, Staphylococcus aureus, serial dilution, MIC, MKC.