Stability Of Method Research Articles

Silencing ACE1 Gene with dsRNA of Different Lengths Impairs Larval Development in Leptinotarsa decemlineata

In the search for effective strategies to control the Colorado Potato Beetle, RNA interference technology has emerged as a promising method due to its capacity to suppress genes selectively. Factors such as the target gene and double-stranded RNA (dsRNA) length are critical for optimizing gene silencing efficiency. In this study, we designed and synthesized in vitro dsRNAs of varying lengths targeting the ACE1 gene, which encodes the AChE1 isoform of acetylcholinesterase in the beetle. All tested dsRNA lengths (222 bp, 543 bp, 670 bp, and 870 bp) promoted transcript reduction. The 670 bp dsRNA was the most effective, reducing transcript levels by approximately 40% by day seven, followed by the 543 bp dsRNA. No significant differences were observed between the 222 bp and 870 bp dsRNAs. Furthermore, all of the dsRNA lengths resulted in reduced weight gain and increased mortality in larvae, with the 670 bp dsRNA showing the highest mortality rate, leaving only 63% larval survival, a trend that persisted through day nine. These findings emphasize that dsRNA length is a key factor in the silencing response, underscoring the importance of selecting the optimal length while considering the gene’s target, stability, and delivery methods. This study contributes to establishing design criteria for dsRNA, aiding in the development of more effective and sustainable pest management strategies.

Phytochemical screening, antioxidant and anti-inflammatory activities of Rosmarinus officinalis medicinal plant from Algeria

This study aims to investigate phytochemical screening, total polyphenol, flavonoids and tannins content, antioxidant activities, and anti-infalammatory effects of methanol, water and ethyl acetate extracts of R.officinalis L growing in Mascara region (Algeria). The extracts were screened for their possible antioxidant activity was determined by DPPH free radical-scavenging and reducing power assay, in vitro anti-inflammatory activity was evaluated by membrane stabilization method using sodium diclofenac as a reference drug. Phytochemical screening of the extracts revealed a presence of tannins (total and gallic), flavonoids, phenols, quinones, coumarins, saponosides, teranoids. and Reducing sugar.. The results showed that methanolic extract significantly (P˂ 0.05) antioxidant than the aqueous and ethyl acetate extract with IC50 values of (5.032 ± 1.003 μg/ml). Furthemore, the ethyl acetate extract showed significantly (P˂ 0.05) inhibition of hypotonicity induced haemolysis 94.36 % at concentration of 250 μg/ml compared to 50 % for sodium diclofenac at 100 μg/ml. The results obtained confirm the traditional therapeutic effects and these plants can be a potential source of anti-inflammatory drug.

An adaptive assessment method of power system transient stability considering PMU data loss

AbstractTransient stability assessment (TSA) plays an important role in ensuring the reliable operation of power systems. With the popularity of phasor measurement units (PMUs), data‐driven TSA methods have been widely concerned. However, the performance of TSA model may deteriorate when data loss occurs due to PMU failure. This paper proposes an adaptive assessment method for transient stability of power systems considering PMU data loss. First, considering the importance of temporal features, a collection of PMU clusters is constructed to minimize the failure risk and maintain full observability of the whole buses of the grid. Secondly, a weighted integrated assessment model based on PMU clusters is constructed by using an improved eXplainable Convolutional neural network for Multivariate time series classification (XCM) as a TSA classifier. The model can make full use of time series information to carry out adaptive TSA and maintain the robustness of the assessment performance even when PMU failure occurs. Finally, it is verified in a modified IEEE 39‐bus system with wind power and solar power. The effect of the proposed method shows high accuracy and strong anti‐noise interference ability in case of data loss.

Active Remote Focus Stabilization in Oblique Plane Microscopy.

Light-sheet fluorescence microscopy (LSFM) has demonstrated great potential in the life sciences owing to its efficient volumetric imaging capabilities. For long term imaging, the light-sheet typically needs to be stabilized to the detection focal plane for the best imaging results. Current light-sheet stabilization methods rely on fluorescence emission from the sample, which may interrupt the scientific imaging and add to sample photobleaching. Here we show that for oblique plane microscopes (OPM), a subset of LSFM where a single primary objective is used for illumination and detection, light-sheet stabilization can be achieved without expending sample fluorescence. Our method achieves ~43nm axial precision and maintains the light-sheet well within the depth of focus of the detection system for hour-long acquisition runs in a lab environment that would otherwise detune the system. We demonstrate subcellular imaging of the actin skeleton in melanoma cancer cells with a stabilized OPM.

A novel linear stability method based on Shakhov Bhatnagar–Gross–Krook equations for Rayleigh–Bénard convection in rarefied gases

A novel linear stability method based on Shakhov Bhatnagar–Gross–Krook equations for Rayleigh–Bénard convection in rarefied gases

A review of herbaceous vegetation effect on mechanical properties of soil for enhancing slope stability

Abstract Slope instability is a critical issue that threatens infrastructure, human settlements, and the environment, with conventional stabilization methods often causing significant environmental disruption and incurring high costs. This study aims to explore the potential of native Southeast Asian plants, especially lemongrass (Cymbopogon citratus), vetiver grass (Chrysopogon zizanioides), elephant grass (Pennisetum purpureum), and alang-alang grass (Imperata cylindrica) to improve soil quality and prevent slope stability. The analysis focuses on their physical and mechanical properties to identify trends and advantages for slope reinforcement and sustainable ecological restoration in Southeast Asia. The findings highlight that lemongrass and vetiver grass demonstrate promising improvements in slope stability parameters, including friction angle, cohesion, and shear strength, making them highly effective for erosion control. Lemongrass shows the most pronounced benefits, while vetiver grass also provides substantial stabilization. In contrast, elephant grass and alang-alang grass offer less improvement in these parameters. The study suggests that future research should explore the hydraulic behavior of these species to better understand their effects on water infiltration, runoff, and soil moisture dynamics, which are crucial for comprehensive slope stability analysis.

A first-order energy stable scheme for the Allen–Cahn equation with the Allen–Cahn type dynamic boundary condition

In this paper we construct and analyze a first-order time marching scheme for the Allen–Cahn equation with the Allen–Cahn type dynamic boundary condition. To hold the mass conservation in the bulk and on the surface respectively, we add two penalty terms to the model. By using the stabilization method, we verify that the scheme is energy stable and is of first-order in time by the error estimates. Finally we present enough numerical results to validate the convergence and the energy stability of such scheme. Moreover, we simulate the shape deformation of a droplet and the moving process of the contact line.

A variationally-consistent hybrid equilibrium element formulation for linear poroelasticity

A poroelastic medium is defined as a continuous system in which the mechanical response arises from the interaction between a deformable elastic solid skeleton and a pressurised fluid, fully saturating the interconnected porous network. The coupled theory of Poromechanics is effectively employed to solve a broad class of problems spanning various fields, ranging from its original application in Geomechanics to addressing contemporary challenges in tissue Biomechanics. Besides the seminal theory introduced by Biot, several variational multi-field principles have been proposed, leading to various finite element formulations. Finite Element approaches are mostly based on a two-field discretisation involving the coupled solid displacement and interstitial fluid pressure as primary variables. However, this choice of the two-primary variables leads to a saddle-point problem, posing a challenge in achieving accurate solutions and thus making the use of stabilisation methods rather mandatory. This study proposes a novel variationally consistent Hybrid Equilibrium Element formulation, based on the complementary strain energy function. A two-field minimisation principle is formulated, with total Cauchy stress and interstitial fluid pressure serving as primary variables. The proposed variational principle provides a variationally consistent framework for designing inherently self-equilibrated Hybrid Equilibrium Elements, where the solid displacement field emerges as a Lagrangian variable to enforce a co-diffusivity constraint at element sides. The fulfilment of the inf-sup condition, typically challenging in developing stable and computationally efficient finite element formulations, is no longer required, a minimisation principle having been adopted, rather than the classical saddle-point principle. The proposed Hybrid Equilibrium Element approach offers a statically admissible solution even in the proximity of singularities or high space gradient stress distribution, providing a more comprehensive assessment of stress distributions and concentrations. The convexity of the new variational principle has been established, ensuring solution uniqueness. The formulation is based on a 2-D triangular Hybrid Equilibrium Element employed to solve plane strain problems. The element has been implemented in the Open source Finite Element Analysis Program (FEAP) and its performance evaluated against classical benchmark problems for poroelasticity, with the emphasis on stress accuracy. The numerical results obtained for the quasi-static analysis of poroelastic systems show the advantages of the proposed approach, in which accurate stress distributions are displayed, even adopting quite coarse meshes. Remarkably, in the proposed approach no stabilisation technique is required.

Investigating the geomechanical behavior and mechanism of clay stabilization with natural zeolite and nano-magnetite under accelerated curing conditions (ACC)

Chemical stabilization is a commonly used technique for ground improvement. Traditional methods of chemical soil stabilization rely on additives such as cement and lime, which are relatively expensive and not environmentally friendly. Therefore, using accessible natural pozzolans, such as zeolite, in soil stabilization is an effective and economical option. This study investigated the effect of zeolite and nano-magnetite on the geomechanical behavior of fine-grained clayey soil. Unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV), and electrical conductivity (EC) tests were performed on both stabilized and unstabilized samples. The samples were cured under standard curing conditions (SCC) and accelerated curing conditions (ACC). The UCS and UPV results for the clay sample containing 5% zeolite and 1% nano-magnetite showed significant increases of 85% and 48% under SCC and 174% and 59% under ACC, respectively, compared to untreated clayey soil. Additionally, the clay mixture containing 5% zeolite and 1% nano-magnetite, which achieved the highest UCS and UPV values under ACC, exhibited increases of 166 kPa and 100 m/s, respectively, compared to SCC. Moreover, the EC value decreased by approximately 51% and 60% for the samples with the highest strength in SCC and ACC, respectively. Based on Scanning Electron Microscope (SEM) imaging and Energy Dispersive Spectroscopy (EDS) analysis, the impact of zeolite and nano-magnetite on improving compaction and promoting hydrothermal reactions was evident, supporting the higher geomechanical results obtained. Overall, the findings suggest that using zeolite and nano-magnetite offers a cost-effective and eco-friendly solution for stabilizing clayey soil in civil engineering projects.

Cobalt-nickel sulfide hierarchical hollow microspheres to boost electrochemical activity for supercapacitors

Cobalt-nickel bimetallic sulfides are promising candidates for supercapacitors due to their high theoretical specific capacity, good electrical conductivity and fast redox kinetics. Nevertheless, they confront challenges such as poor cycling stability, volume expansion, and complicated synthesis methods. To address these issues, in this work, a MOF-assisted synthesis strategy is developed to achieve the one-pot formation cobalt-nickel sulfide hollow microspheres. The 2D nanosheet-constructed hierarchical hollow configuration promotes rapid electron/ion transfer, provides more active sites and effectively mitigates volume expansion during cycling. The optimized Co1Ni4S exhibits high electrochemical performance, such as a specific capacity of 277.2 mA h/g (2217 F g−1) at 1 A g−1, remarkable cycling stability with ∼100 % retention after 5000 cycles, and favorable rate capability with 84.8 % retention at 20 A g−1. Furthermore, an aqueous asymmetric supercapacitor (ASC) assembled with the Co1Ni4S and active carbon (AC) derived from lotus pollen achieves an energy density of 86.9 Wh kg−1 at 800.1 W kg−1, along with significant cycling stability (97.1 % retentions over 30,000 cycles). These superior results showcase a simple one-step method for developing superior-performing electrode materials applicable to advanced supercapacitors.

Eco-friendly synthesis of ZnO nanoparticles fabricated using Fioria vitifolia L. and their Biomedical Potentials

The present study aimed to environmentally friendly synthesis of ZnO NPs using Fioria vitifolia leaf extracts which provides a sustainable and green approach for production of NPs. The produced ZnO NPs were evaluated using various spectrum approaches (UV-vis, FTIR XRD, TEM and EDAX). The synthesized ZnO NPs was confirmed by UV-Visible spectroscopy exhibited a peak at 370 nm. SEM imaging revealed a flash-like and needle-like bottom morphology. Fourier-transform infrared spectroscopy (FTIR) analysis detected vibrations corresponding to alcohols, halides, and aromatics functional groups. TEM showed spherical-shaped NPs with an average diameter of 11 nm. XRD analysis exhibited distinct peaks at 2θ values of 31.7°, 34.3°, 36.2°, 47.4°, 56.6°, 62.8°, 66.4°, 67.9°, 69.1°, and 76.8°, corresponding to the crystallographic planes (100), (002), (101), (102), (110), (103), (200), (112), (201), (004), and (202) planes respectively. The antibacterial activity demonstrated significant zones of inhibition against E. coli (17±0.6 mm) and S. aureus (23.7±0.5 mm), and inhibition of biofilm formation in S. aureus and C. albicans. Additionally, S. mutans exhibited the highest sensitivity to the minimum inhibitory concentration (MIC) of ZnO NPs, with complete inhibition occurring at 7.5 μg/mL. Furthermore, antioxidant DPPH assays exhibited IC50 values of 42 μg/mL. Additionally, the anti-inflammatory properties of ZnO NPs of F. vitifolia were evaluated in-vitro using models utilizing the human red blood cells (HRBC) membrane stabilization method (MSM), and it was shown to have an MSM of 83.87% at 250 μg/mL. Furthermore, ZnO NPs exhibited anticancer activity against the MDA-MB-231 breast cancer cell line with an IC50 value of 35.50 μg/mL. Toxicological evaluation of FV-ZnO nanoparticles in zebrafish (Danio rerio) embryos indicated low toxicity at maximum concentration. These is first findings suggest that ZnO NPs synthesized from F. vitifolia leaf extracts possess significant antibacterial, antioxidant, anti-inflammatory, and anticancer properties. Additionally, their low toxicity in zebrafish embryos makes them suitable for further development in antimicrobial therapies with minimal side effects, offering a sustainable, biocompatible solution to tackle multidrug-resistant microbial infections.

Effect of Flax By-Products on the Mechanical and Cracking Behaviors of Expansive Soil.

Expansive soils, prone to significant volume changes with moisture fluctuations, challenge engineering infrastructure due to their swelling and shrinking. Traditional stabilization methods, including mechanical and chemical treatments, often have high material and environmental costs. This study explores fibrous by-products of flax processing, a sustainable alternative, for reinforcing expansive clay soil. Derived from the Linum usitatissimum plant, flax fibers offer favorable mechanical properties and environmental benefits. The research evaluates the impact of flax tow (FT) reinforcement on enhancing soil strength and reducing cracking. The results reveal that incorporating up to 0.6% randomly distributed FTs, consisting of technical flax fibers and shives, significantly improves soil properties. The unconfined compressive strength (UCS) increased by 29%, with 0.6% FT content, reaching 525 kPa, compared to unreinforced soil and further flax tow additions, which led to a decrease in UCS. This reduction is attributed to diminished soil-fiber interactions and increased fiber clustering. Additionally, flax tows effectively reduce soil cracking. The crack length density (CLD) decreased by 6% with 0.4% FTs, and higher concentrations led to increased cracking. The crack index factor (CIF) decreased by 71% with 0.4% flax tows but increased with higher FT concentrations. Flax tows enhance soil strength and reduce cracking while maintaining economic and environmental efficiency, offering a viable solution for stabilizing expansive clays in geotechnical applications.

Ether‐Free Alkaline Polyelectrolytes for Water Electrolyzers: Recent Advances and Perspectives

AbstractAnion exchange membrane (AEM) water electrolyzers (AEMWEs) have attracted great interest for their potential as sustainable, environmentally friendly, low‐cost sources of renewable energy. Alkaline polyelectrolytes play a crucial role in AEMWEs, determining their performance and longevity. Because heteroatom‐containing polymers have been shown to have poor durability in alkaline conditions, this review focuses on ether‐free alkaline polyelectrolytes, which are more chemically stable. The merits, weaknesses, and challenges in preparing ether‐free AEMs are summarized and highlighted. The evaluation of synthesis methods for polymers, modification strategies, and cationic stability will provide insights valuable for the structural design of future alkaline polyelectrolytes. Moreover, the in situ degradation mechanisms of AEMs and ionomers during AEMWE operation are revealed. This review provides insights into the design of alkaline polyelectrolytes for AEMWEs to accelerate their widespread commercialization.

Innovative multi-trial breeding and genotype screening in triticale (x Triticosecale Wittmack) for enhanced stability under drought stress.

Triticale is a man-made crop produced by crossing wheat (Triticum aestivum) and rye (Secal cereal) with the aim of increasing the adaptability and potential production of its parental line (wheat) under environmental stresses and harsh conditions. Accordingly, the objectives of this study are as follow, a: compare different stability measurement methods regarding their suitability, b: identify most stable genotypes for cultivar release, and c: provide a freely available package in R programming language (named 'Stbidx') capable of exploiting all stability methods for similar studies. Accordingly, 30 triticale genotypes were evaluated for their stability and adaptability to changing environments during four consecutive years from 2016 to 2020 in different locations in Iran (one year in Zarghan, two years in Ghorveh, one year in Sanandaj) and under two different irrigation regimes (normal irrigation and water deficit stress conditions). All 30 triticale genotypes were cultivated in a randomized complete block design (RCBD) with three replications in each environment (12 environments: 6 trials in 2 conditions). Grain yield of triticale genotypes was measured and it applied to calculate all known stability indices (univariate methods) along with the meta-analysis models were evaluated in this study. Additionally, two novel techniques (Stability ID: SID and AMMI PC Value: APCV) were introduced and successfully tested for screening stable genotypes. These methods were introduced to improve and resolve the limitation of the previous stability methods. Meanwhile, heatmap analysis, as a proper data-mining technique, has been successfully applied for the first time to find stable genotypes in different environments in this study. The results clearly indicated a higher suitability of our introduced methods over previous multi-trials screening methods. Based on our methods and considering all environments, triticale genotypes ELTTCL21 (SID = 8.00; APCV = 28.12), ELTTCL25‌ (SID = 8.14; APCV = 30.02), ELTTCL30 (SID = 8.43; APCV = 17.00), ET-90-8 (SID = 14.00; APCV = 42.05), and Sanabad (SID = 10.57; APCV = 12.44) were among stable genotypes and they can be nominated as new cultivars. Additionally, for stress condition genotypes ELTTCL30 (stress: 380.6g/m2) and ELTTCL18 (stress: 360.79g/m2) and for normal condition genotypes ET-90-4 (normal: 849.4g/m2) and ELTTCL20 (normal:845g/m2) were respectively the most proper genotypes with the highest production to be considered for each condition separately.

Biomechanical Comparison of Spacer Pin Fixation to Two Established Methods of Tibial Tuberosity Transposition Stabilization in Dogs.

The aim of this cadaveric study was to compare the biomechanical outcomes of three methods of stabilization for tibial tuberosity transposition to treat medial patellar luxation: a complete osteotomy with a two-pin and tension band wire (TBW) fixation (TBW group), a partial osteotomy with a two-pin fixation (2 Pin group), and a partial osteotomy with a spacer pin fixation (Spacer Pin group). Thirty medium to large-sized canine cadaveric tibiae were dissected and randomly assigned to one of three groups: TBW, 2 Pin, and Spacer Pin groups. The patellar ligaments were loaded in tension until ultimate failure. Ultimate failure force and mode of failure were documented, stiffness was calculated, and the results were compared statistically between the three treatment groups. There were not any significant differences in ultimate failure force or stiffness between groups. All groups predominantly failed by patellar ligament failure, with distal tibial crest fracture/displacement being the second-most common mode in the 2 Pin and Spacer Pin groups. The mechanical properties of the spacer pin stabilization were not different from the TBW and 2 Pin groups. The spacer pin technique could be an alternative way to stabilize tibial tuberosity following tibial tuberosity transposition with a partial osteotomy based on this cadaveric load-to-failure model.

The Punch Graft Technique: A Simplified Protocol for Three-Dimensional Peri-Implant Soft and/or Hard Tissue Augmentation in a Single Step.

This article describes a clinical protocol utilizing soft tissue augmentation alone or in combination with guided bone regeneration (GBR), introducing simultaneous application of the one abutment one time concept for three-dimensional reconstruction of the deficient ridge. Soft and hard tissue quality and dimensions are fundamental elements for long lasting results in implant dentistry. Different techniques have been described for soft and hard tissue augmentation at time of implant placement presenting favorable results. However, multiple abutment disconnections during the prosthetic phase of treatment can compromise the results achieved during surgery. The purpose of this article is to present a surgical protocol that allows three-dimensional ridge reconstruction involving soft tissue augmentation alone, or in combination with hard tissue augmentation in one single step with the use of an one-time intermediate abutment as an anchorage device for the regenerative materials. Two clinical cases utilizing the proposed protocol are also presented, demonstrating favorable results. The application of the proposed protocol simplifies the surgical phase of treatment, protects the achieved result and enables a favorable outcome in decreased time. Utilising an intermediate abutment as an anchorage device at time of surgery can be proven an easy to apply and biologically favorable alternative way to other methods of soft tissue graft stabilization proposed in the past.

Blind 3D Video Stabilization with Spatio-Temporally Varying Motion Blur

Video stabilization is a challenging task that attempts to compensate for the overall frame shake during video acquisition. Existing three-dimensional video stabilization methods aim at modeling camera perspective projection through either data-driven training or explicit motion estimation. However, the above methods are difficult to effectively solve the issue of shaky videos with abrupt object movements, resulting in local motion blur in the direction of the movement. This phenomenon is prevalent in real-world scenarios featuring foreground blind motion scenes. Unfortunately, directly combining stabilization and deblurring methods poses challenges when dealing with this situation. In the video, the intensity of motion blur undergoes continuous changes, and the direct combination method inadequately utilizes spatiotemporal information, providing insufficient clues for cross-frame compensation. To alleviate this problem, the Cross-frame-temporal Module framework is proposed to address blind motion blur induced by various conditions, which utilizes cross-frame temporal features to estimate depth maps and camera motion. In this framework, a Blur Transform Network (BTNet) is designed to adapt to spatially varying motion blur, which transforms local regions according to the impact of blur intensities to adapt to the effects of non-uniform motion blur; furthermore, our Temporal-Aware Network (TANet) further suppresses motion blur by leveraging cross-frame temporal features. In addition, the limited availability of pair-training video data containing motion blur limits the application of this approach in practice. The Cross-frame-temporal Module framework adopts an un-pretrained in-test training strategy. Extensive experimental results have demonstrated that our method outperforms state-of-the-art methods.

Mechanical Performance and Life Cycle Assessment of Soil Stabilization Solutions for Unpaved Roads from Northeast Brazil

This article presents the results of laboratory tests conducted to identify the granulometric stabilization and chemical improvement techniques used in an experimental segment of the unpaved BR-030 highway in the Maraú Peninsula, Bahia. The segment was designed to evaluate the performance of primary coating sections stabilized with sand, clayey gravel, reclaimed asphalt pavement (RAP), and simple graded crushed stone (GCS), as well as chemically improved with Portland cement and hydrated lime. The laboratory campaign focused on mechanical resistance, resilient modulus, and permanent deformation tests. In this research, chemical improvement with the addition of 2% Portland cement presented the most promising results for potential application in the section of the BR-030 highway intended to remain unpaved. Additionally, a life cycle assessment (LCA) revealed that mechanical stabilization of the primary coating has the lowest environmental impacts, making it a suitable and sustainable option among stabilization methods.

Briquetting of black soldier fly frass as a post-harvest stabilization strategy

ABSTRACT The production–consumption cycle needs a transition towards a circular economy where waste valorization is included. This study investigated briquetting as a stabilization method for black soldier fly frass (BSFF) with faecal matter, pig manure, and poultry manure as the larvae feed. Herein, dried BSFF was pyrolyzed at 350 °C for 2 h to produce biochar then mixed with charcoal dust in equal ratio to produce biobriquettes through densification, with cassava gel (10 wt%) as binder. One-way ANOVA showed statistical significance in carbon, nitrogen, hydrogen, and oxygen. There were significant differences (p < 0.05) between the calorific value, moisture content, ash content, volatile matter, and fixed carbon of the briquettes. The fixed carbon, volatile matter, moisture, and ash content ranged from 29.66 ± 0.86 to 42.01 ± 0.92, 29.26 ± 0.52 to 32.59 ± 0.80, 2.95 ± 0.1 to 5.08 ± 0.04, and 21.48 ± 0.14 to 37.20 ± 0.29, respectively. The calorific value of the produced briquettes ranged from 16.25 ± 0.57 to 20.70 ± 0.53 MJ/kg, which exceeds the minimum requirement of 14.5 MJ/kg recommended for non-woody briquettes. During combustion, concentrations of NOx, N2O, CO, and CO2 varied significantly across the treatments with the acacia charcoal having the highest concentration of CO. Briquetting is a potential stabilization method for frass resulting in waste reduction, bioenergy production, reduced adverse effects of climate change, and enhanced sustainability.

Anti –Inflammatory Activity of Propolis Trigona sp. Water Extract from North Lombok with Red Blood Cell Membrane Stability Method

Propolis is a bee product that can be used as an anti-inflammatory. Cultivation of propolis-producing bees is also carried out in North Lombok. However, propolis has not been utilized optimally by the people of North Lombok. Apart from that, testing of North Lombok propolis is still limited to the chemical content and antioxidant activity of propolis extracted with ethanol solvent. Therefore, this study aims to determine the activity and effective concentration of North Lombok propolis water extract as an anti-inflammatory using the red blood cell membrane stability method. Groups include control groups such as positive control (diclofenac sodium), negative control (distilled water), and test groups (propolis water extract concentrations of 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, 25%, 27.5%, and 30%). In The first step human blood was centrifuged of human blood, and then part of the red blood cells (sediment) was taken and saline was added to obtain a red blood cell suspension. Next, mixing the test solution was carried out in the order of 0.5 ml of red blood cell suspension, then 0.5 ml of extract was added (0.1% w/v Na-diclofenac solution in the positive control, distilled water in the negative control), 1 mL of buffer solution and 2 mL of hyposaline solution, then homogenized. Each group was incubated at 37°C for 30 minutes, then centrifuged for 10 minutes at 3000 rpm. The supernatant was taken, and the absorbance was read with a UV-Vis spectrophotometer at 560 nm. Next, the percentage value of red blood cell hemolysis protection was calculated. The data obtained were tested statistically using One-way ANOVA and post-hoc (LSD) tests SPSS version 29. The results showed that propolis water extract concentrations were 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, 25%, 27.5%, and 30% have anti-inflammatory activity because they can increase the stability of the red blood cell membrane with a percentage of hemolysis protection of respectively 57.92%, 59.99%, 60.99%, 61.99%, 64.31%, 69.59%, 75.07%, 79.77% and 84.45%. Propolis water extract concentrations of 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, and 25% had anti-inflammatory effects that were not significantly different from the positive control (p>0.05). The 27.5 % and 30% concentrations had a higher percent hemolysis protection value than the positive control (p<0.05).