Antibacterial and antibiofilm activities of Prangos acaulis Bornm. extract against Streptococcus mutans: an in silico and in vitro study

Introduction: Streptococcus mutans is a principal pathogenic agent in biofilm formation on the teeth surfaces and subsequently development of dental caries and plaque. Therefore, currently introducing novel anti-bacterial and anti-biofilm agents, especially plant based materials are highly regarded. This study was planned to investigate in silico and in vitro antibacterial activities of Prangos acaulis extracts against S. mutans in single and biofilm forms and their mutagenicity in Ames test. Methods: The anti-bacterial and anti-biofilm effects of methanol extracts from various parts of P. acaulis were evaluated using disk diffusion and microtiter assay. Moreover, the potential mutagenicity of the extracts was investigated using Ames test. In addition, dominant constitutes of P. acaulis that reported in previous studies were subjected to an in silico analysis. The ability of selected phytochemicals to inhibit the glucosyltransferase was evaluated using molecular docking method. Results: All tested extracts especially root extract had significant antibacterial activity against the single form of S. mutans and inhibited biofilm formation without any mutagenic activity. The results also confirmed that three compounds consisting of ar-curcumene, d-limonene and alpha-pinene had strong and appropriate interactions to glucosyltransferase. Conclusion: This study indicated that P. acaulis has potent antibacterial and biofilm inhibition activity against S. mutans and can be good candidate for in vitro and in vivo studies with the aim of introducing novel inhibitors of dental caries developmen

Water Treatment Process Options for Gravity-Feed System of Rural Water Supply Scheme in Western Sarawak

Water resource is abundant in Malaysia. The renewable water resource from both surface water and groundwater is about 630 billion cubic meters. About 97 percent of the rivers in Malaysia are abstracted for public water supplies. This contributes to the establishment of 487 water treatment plant intake points in Peninsular Malaysia and 91 in Sarawak. The number does not include the number of water treatment plants established in the State of Sabah. Nevertheless, the nation aspiration of overarching vision 2020 to achieve the fully developed nation status has caused impacts to the national water resources because of the rapid pace of socio-economic development. The stakeholders have started expressing their concern on the issues of freshwater scarcity because of apparent degradation in water quality standard. Furthermore, the land-use developments have extended into the rural areas to exploit the natural resources for economic purposes. Consequently, the pollutions generated from unregulated development activities have caused environmental impacts and scarcity of freshwater sources from designated water supply catchment areas. Since the urban populations are getting their water sources from major river basins, which are larger, the populations living in remote rural areas are experiencing the opposite. In the State of Sarawak, 60 percent of the population are living in the remote rural areas. They get their water supply from freshwater sources that come from smaller water catchments provided by the State Health Department, known as the gravity-feed water catchment. In this regard, only designated first-priority water catchments with sources that comply with the requirement of the drinking water quality standards as well as passing the catchment sanitary survey are chosen for development as gravity-feed systems. Because of the high raw water quality, the villages are supplied with these sources as their drinking water, through piped-gravity water without the provision of any basic treatment. The communities are only advised to boil their water for safety reasons. The State Health Department carries out routine drinking water quality surveillance programmes to monitor the water quality from the gravity-feed systems. In 2002, there are 2,730 gravity-feed system established in Sarawak.These gravity-feed systems are developed by the State Health Department. The purpose of this study is to determine the conditions of raw water quality from various State Health Department gravity-feed systems as of whether these raw waters are still safe as drinking water for the rural populations. Due to some constraints and limitations, only water quality data from selected water catchments in three districts of Western Sarawak, namely, Lundu, Serian and Betong are used for the study. In addition, the study is trying to determine the best available solution to overcome the water quality problems by finding a feasible and economical water treatment process options to enhance existing practice adopted by the State Health Department for the rural water supply

In Silico Screening Hepatitis B Virus DNA Polymerase Inhibitors from Medicinal Plants

Abstract Background: Hepatitis B virus infection (HBV) is a significant global health problem and is a major cause of morbidity and mortality worldwide. Therefore, currently, introducing novel anti Hepatitis B drugs is taken into consideration. This study was planned to in silico screening novel Hepatitis B virus DNA polymerase inhibitors from two medicinal plants Terminalis chebula and Caesalpinia sappan. Materials and Methods: This is a descriptive-analytic study. In the study, three-dimensional structure of the Hepatitis B virus DNA polymerase was predicted using homology modeling method. A set of phytochemicals from mentioned plants were retrieved from Pubchem database in SDF format. In silico screening was carried out using molecular docking between mentioned phytochemicals and modeled polymerase by iGemdock 2.1 software. Results: Results of the study confirmed that all evaluated ligands have appropriate interactions to the polymerase with least toxicity and without genotoxicity potential. Results also showed that most interactions occur in reverse transcriptase domain which located in 354-694 area in the amino acid sequence of tested polymerase. Analysis of energy and amino acids involved in ligand-polymerase interaction revealed that Terchebin, Chebulinic Acid and Terflavin A have more effective interaction with the polymerase in compared to other ligands. Conclusion: Based on the results it can be concluded that evaluated compounds could be good candidates for in vitro and in vivo research in order to develop novel anti- Hepatitis B drugs

Geotechnical Aspects of Explosive Compaction

Explosive Compaction (EC) is the ground modification technique whereby the energy released from setting off explosives in subsoil inducing artificial earthquake effects, which compact the soil layers. The efficiency of EC predominantly depends on the soil profile, grain size distribution, initial status, and the intensity of energy applied to the soil. In this paper, in order to investigate the geotechnical aspects, which play an important role in performance of EC, a database has been compiled from thirteen-field tests or construction sites around the world, where EC has been successfully applied for modifying soil. This research focuses on evaluation of grain size distribution and initial stability status of deposits besides changes of soil penetration resistance due to EC. Results indicated suitable EC performance for unstable and liquefiable deposits having particle sizes ranging from gravel to silty sand with less than 40% silt content and less than 10% clay content. However, EC is most effective in fine-to-medium sands with a fine content less than 5% and hydraulically deposited with initial relative density ranging from 30% to 60%. Moreover, it has been observed that EC can be an effective method to improve the density, stability, and resistance of the target soils

Callogenesis in root explants of four species of the family Solanaceae after inducing by Agrobacterium rhizogenes

Studying explants affected by Agrobacterium rhizogenes shows that in addition to possible formation of hairy roots, it is likely that callogenesis can be induced in these tissues. The T-DNA region of A. rhizogenes codes enzymes that participate in biosynthesis of plants growth hormones. These hormones also affect callogenesis, hence, the formation of various calluses with different morphological properties are possible. It is very likely that the level of biosynthetic growth hormone, the plasmid carried by each bacteria strain, the position of T-DNA, and the level of gene expression contribute to this morphologic variation. In this study, the root explants of four species of the family Solanaceae namely Atropa belladonna, Datura metel, D. stramonium and Hyoscyamus niger were induced by using different strains of A. rhizogenes (A4, A7, AR15834, AR318, AR9402 and AR9543). Some of these explants entered callus phase and formed various calluses with different colors and shapes. Moreover, in some callus samples hairy roots were also appeared. These variations were probably caused by variations in the levels and ratios of auxin and cytokinine hormons after the induction. As shown in previous studies, the amount of secondary metabolites is reduced due to undifferentiated tissue produced in the callogenesis process

Antibacterial and antibiofilm activities of Prangos acaulis Bornm. extract against Streptococcus mutans: an in silico and in vitro study

Introduction: Streptococcus mutans is a principal pathogenic agent in biofilm formation on the teeth surfaces and subsequently development of dental caries and plaque. Therefore, currently introducing novel anti-bacterial and anti-biofilm agents, especially plant based materials are highly regarded. This study was planned to investigate in silico and in vitro antibacterial activities of Prangos acaulis extracts against S. mutans in single and biofilm forms and their mutagenicity in Ames test. Methods: The anti-bacterial and anti-biofilm effects of methanol extracts from various parts of P. acaulis were evaluated using disk diffusion and microtiter assay. Moreover, the potential mutagenicity of the extracts was investigated using Ames test. In addition, dominant constitutes of P. acaulis that reported in previous studies were subjected to an in silico analysis. The ability of selected phytochemicals to inhibit the glucosyltransferase was evaluated using molecular docking method. Results: All tested extracts especially root extract had significant antibacterial activity against the single form of S. mutans and inhibited biofilm formation without any mutagenic activity. The results also confirmed that three compounds consisting of ar-curcumene, d-limonene and alpha-pinene had strong and appropriate interactions to glucosyltransferase. Conclusion: This study indicated that P. acaulis has potent antibacterial and biofilm inhibition activity against S. mutans and can be good candidate for in vitro and in vivo studies with the aim of introducing novel inhibitors of dental caries development