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The microbial-induced calcite precipitation (MICP) technique has been developed as a sustainable methodology for the improvement of the engineering characteristics of sandy soils. However, the efficiency of MICP-treated sand has not been well established in the literature considering cyclic loading under undrained conditions. Furthermore, the efficacy of different bacterial strains in enhancing the cyclic properties of MICP-treated sand has not been sufficiently documented. Moreover, the effect of wetting-drying (WD) cycles on the cyclic characteristics of MICP-treated sand is not readily available, which may contribute to the limited adoption of MICP treatment in field applications. In this study, strain-controlled consolidated undrained (CU) cyclic triaxial testing was conducted to evaluate the effects of MICP treatment on standard Ennore sand from India with two bacterial strains: Sporosarcina pasteurii and Bacillus subtilis. The treatment durations of 7 d and 14 d were considered, with an interval of 12 h between treatments. The cyclic characteristics, such as the shear modulus and damping ratio, of the MICP-treated sand with the different bacterial strains have been estimated and compared. Furthermore, the effect of WD cycles on the cyclic characteristics of MICP-treated sand has been evaluated considering 5–15 cycles and aging of samples up to three months. The findings of this study may be helpful in assessing the cyclic characteristics of MICP-treated sand, considering the influence of different bacterial strains, treatment duration, and WD cycles.

For the characterization of fiber-reinforced soil under static loading conditions, there is a wealth of literature. However, study on the dynamic behavior of fiber-reinforced soil is very limited. Now that earthquakes are occurring frequently around the world, the dynamic soil analysis has become important for all classes of geotechnical engineering problems. Through numerical simulation of triaxial specimens, the current study explores the behaviour of fiber-reinforced cohesionless soil. The numerical model was validated using existing laboratory triaxial compression testing literature. The stress–strain response of fiber-reinforced sand has been investigated using static and cyclic triaxial testing, as well as other combinations of fiber contents. Fiber-reinforced sand is tested for bulk modulus, shear modulus, and damping values. Effects of fiber contents on static and dynamic stress–strain response of fiber-reinforced soil are highlighted. It has been observed from results that, with an increase in fiber content modulus of elasticity, bulk modulus and shear modulus values increase while damping coefficients decrease for the same. It is believed that the highlighted numerical approach will be an alternative to laboratory experiments to determine the dynamic properties of fiber-reinforced soil.

Studies are being carried out on achieving the maximum quality of garlic through various approaches. In Bangladesh, new garlic varieties (BARI 1–4, BAU-1, BAU-2, BAU-5) have been recently developed by artificial selection to enhance their quality. The present study aimed to evaluate their potency in terms of bioactive properties and organosulfur compounds content using different bioassay and GC–MS techniques while comparing them with other accessible varieties (Chinese, Indian, Local). The new variety, BARI-3 showed the highest antioxidant activity and total phenolic content. It was also found with the highest level of a potent blood pressure-lowering agent, 2-vinyl-4H-1,3-dithiine (78.15 %), which is never reported in any garlic at this percentage. However, the local variety exhibited greater inhibitory properties against the tested organisms including multidrug-resistant pathogens compared to other varieties. This study primarily shows the potential of these two kinds of garlic for their further utilization and development.

Overuse of antimicrobial drugs has led to selective resistance to existing antibiotics, necessitating the development of different and improved alternatives. Natural substances, particularly those derived from plants, are well-known for their therapeutic characteristics, including antibacterial and antifungal properties. Over the last decade, several pharmacological investigations on medicinal plants have been carried out based on their traditional uses in complementary therapies. In our current study, we have evaluated the pharmacological properties of Mesua ferrea seed ethanolic extract. To test their antioxidant properties, a 1,1-diphenyl-2-picryl-hydrazyl (DPPH)-radical scavenging activity test was performed. Using the agar well diffusion method, the antimicrobial activity of ethanolic extracts of M. ferra seed was investigated against four bacteria such as Salmonella typhi, Bacillus cereus, Staphylococcus aureus and Escherichia coli. The ethanol extract of M. ferra seed was shown to be efficient against gram positive and gram-negative bacteria in this investigation, although Salmonella typhi, Escherichia coli. Demonstrated resistance to this extract. The results revealed that gram positive bacteria were more sensitive than gram negative bacteria to the ethanolic extract of M. ferra seed at all concentrations utilized (from 20 μL to 100 μL). The lowest inhibition zone was produced by a dose of 20 μL with an inhibition zone equal to 11 mm and 14.33 mm, while the maximum inhibition zone was produced by a high concentration of 100 μL with an inhibition zone 19.33 mm and 18 mm against Bacillus cereus and Staphylococcus aureus respectively. Gas Chromatography-Mass Spectroscopy (GC-MS) was performed to identify the compounds in the extract to determine their pharmacological effects and then we performed in-silico experiments to determine the biological activity of the compounds. We have concluded from the study that M. ferrea seed can be a potential source for lead compound development.