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Lactic Acid Bacteria Isolated from Poultry: Phenotypic Characterization Based on Total Plate Count, Gram Staining Test and Hemolytic Activity
No full textThis study aims to characterize lactic acid bacteria (LAB) isolated from the ileum of broiler chickens and native chickens based on total colony count, Gram reaction, and hemolytic activity. Samples were isolated from the small intestine contents of five broiler chickens and five native chickens aged 35 days using selective de Man Rogosa and Sharpe Agar (MRSA) media. The research methodology included Total Plate Count (TPC) counting, Gram staining for cell morphology identification, and hemolysis testing on blood agar media for preliminary safety assessment. The TPC test results showed that the microbial population in broiler chickens (range 2,0×107 to 2,7×107 CFU/ml) was significantly higher than in native chickens (range 3,1×106 to 5,8×106 CFU/ml) based on an independent t-test (p < 0,05). Isolates selected from the group with the highest TPC were identified as Gram-positive rod-shaped (bacilli) bacteria. In the hemolytic activity test, the isolates showed γ-hemolysis (non-hemolytic) characteristics, which were marked by the absence of clear zones around the colonies on blood agar media. The LAB isolates obtained met the initial safety criteria as probiotic candidates due to their non-pathogenic nature, which does not lyse red blood cells. These isolates have the potential to be further developed as poultry feed additives
The structure design and application of metamaterials with negative Poisson's ratio
No full textMetamaterials with negative Poisson's ratio, also called auxetic metamaterials, are artificially engineered structures or materials that possess extraordinary auxetic effect, high shear modulus, excellent impact resistance, and remarkable energy absorption capability. They have been widely applied in aerospace, transportation equipment, mechanical automation, and biomedical engineering. The unique properties of metamaterials are generally determined by the geometry and arrangement of their unit cells. However, due to the structural complexity and microscale dimensions of these cells, traditional manufacturing methods often fail to meet precision requirements, which has significantly restricted research progress in this field. In recent years, with the continuous advancement and maturation of additive manufacturing technology, it has become possible to fabricate complex and delicate microstructures, providing new opportunities for the development and practical application of auxetic materials. This paper focuses on the deformation mechanisms, mechanical properties, and structural characteristics of auxetic metamaterials. It provides an in-depth summary of the physical models of auxetic unit cells, such as re-entrant polygon and rotating rigid unit structures, and explores their wide applicability. Finally, the challenges and future prospects of auxetic metamaterials are summarized, aiming to provide valuable insights and references for the further development and practical applications of auxetic metamaterials and structures
Nanoencapsulation of bioactive compounds in chocolate products: A bibliometric study
No full textThis study aims to map global research trends in the nanoencapsulation of bioactive compounds in chocolate products using a bibliometric analysis. Data were obtained from the Scopus database and analyzed using VOSviewer software for publications published between 2015 and 2025. The results indicate an increasing interest in research on the use of nanoencapsulation technology in chocolate formulations, particularly to support the development of functional foods with higher antioxidant activity. The direction of functional chocolate research is influenced by a country's role in the global cocoa supply chain. Cocoa-producing countries tend to focus on raw material utilization and potential bioactive compounds, while countries with established chocolate industries and high consumption levels place greater emphasis on formulation, processing technology, and functional enrichment of chocolate products. Keyword co-occurrence analysis indicates the dominance of topics such as bioactive compounds, antioxidant activity, encapsulation, and various chocolate formulation approaches. In general, incorporating bioactive compounds into chocolate aims to enhance its functional value without compromising product quality. However, most research still focuses on extracts from fruits, leaves, and spices, while bioactive sources from oil-producing plants remain relatively underexplored, opening up opportunities for further research in the field of functional chocolate
Performance of Alginate-Based Coatings in Liquid Smoke Encapsulation
No full textLiquid smoke contains bioactive compounds such as phenols, carbonyls, and organic acids that function as antimicrobial and antioxidant agents. However, its major limitation is its high volatility, which requires protection through encapsulation. This study aimed to determine the characteristics of encapsulated liquid smoke using the coacervation technique with various coating materials, including alginate (A), alginate+gum arabic (AA), alginate+chitosan (AK), alginate+tapioca (AT), and alginate+maltodextrin (AM), as well as two drying methods, cabinet dryer (CB) and open air drying (OA). The results showed that the two factors coating material and drying method significantly affected the total phenol, total acidity, total carbonyl content, encapsulation efficiency, and loading capacity. Total phenol range from 0.75–3.20%, total acidity from 1.72– 4.33%, and total carbonyl content from 6.26–11.53%. AK combination produced the highest retention of phenols, acids, and carbonyls, as well as the highest encapsulation efficiency and loading capacity
La Génération Z et la supervision en milieu clinique : aligner les attentes avec l’apprentissage par compétences
No full textDans les formations en sciences de la santé, l’enseignement clinique se trouve actuellement à l’intersection de deux dynamiques majeures : l’arrivée d’apprenants issus de la Génération Z et l’implantation d’une réforme de l’éducation médicale fondée sur les compétences. L’articulation entre ces dynamiques et la convergence de leurs attentes respectives demeurent encore peu explorées, bien que les cliniciens superviseurs occupent une position centrale dans leur mise en œuvre. L’examen critique des représentations associées à la Génération Z, confronté aux données issues de la littérature scientifique, pourrait contribuer à orienter l’évolution des pratiques pédagogiques en milieu clinique
Antioxidant activity of catfish (
No full textProtein hydrolysis using alcalase enzyme yields a high degree of hydrolysis, generating bioactive peptides with potential applications as nutraceuticals and functional food ingredients. Striped catfish (Pangasius sp.), characterized by its high protein and moderate fat content, represents a promising source of antioxidant peptides. This study aimed to evaluate the antioxidant activity of striped catfish protein hydrolysates produced by alcalase hydrolysis and subsequently fractionated using ultrafiltration. Hydrolysis was conducted with alcalase at concentrations of 1%, 2%, and 3%, followed by ultrafiltration through a 3 kDa MWCO membrane. Antioxidant activity was assessed using DPPH and ABTS assays. The highest degree of hydrolysis (43.37%) was observed at 3% enzyme concentration. The <3 kDa fraction exhibited strong antioxidant activity with IC50 values of 21.97 ppm (DPPH) and 3.28 ppm (ABTS). These findings demonstrate that ultrafiltration effectively produces smaller peptides with enhanced antioxidant activity
Enhancing marine-derived functional drinks with natural antioxidants: A sustainable approach using seaweed and indigenous botanicals
No full textSeaweed is a marine biomass known for its dietary fiber, bioactive compounds, and hydrocolloids. Carrageenan extracted from seaweed is suitable for the health-promoting beverages. Jelly drinks, while popular in the market, especially among children, often contain high levels of sugar and low nutritional value. This study aimed to formulate antioxidant-enriched functional jelly drinks by incorporating Kappaphycus alvarezii with natural colorants from roselle, curcuma, and beetroot. Formulations using different seaweed porridge -to-water ratios (1:8, 1:9, 1:10 V/V) were evaluated through hedonic sensory testing. The 1:10 ratio was found to be the most preferred based on overall liking. The selected formula was enriched with indigenous botanical at concentrations of 5% and 10% (w/w), respectively. Among these, the 10% concentration of each is better than 5% concentration. At this level, the antioxidant activity by DPPH assay IC50 values of 1153.08 ppm (roselle), 537.40 ppm (curcuma), and 409.04 ppm (beetroot). Meanwhile, the dietary fiber content in the control and botanical-enriched samples ranged from 1.88 to 2.82% (w/w). The selected product (1:10 seaweed porridge:water with 10% coloran) contained 83.89% water, 0.20% ash, 0.17% protein, 0.39% fat, 1.93% dietary fiber, and 15.42% carbohydrate. The addition of indigenous botanicals not only enhanced antioxidant capacity but also improved consumer acceptability at certain level
Role of inertia in the dynamics of a thin film falling over a heated vertical cylindrical fiber
No full textThis work investigates the linear stability of a thin liquid film flowing down a uniformly heated vertical cylindrical fiber. A fourth-order nonlinear evolution equation governing the spatiotemporal dynamics of the film thickness is derived using lubrication approximation and asymptotic expansion. The model captures the influence of gravity, inertia, surface tension, thermocapillarity, and convective heat transfer through key dimensionless parameters: Bond, Reynolds, Marangoni, and Biot numbers. Temporal stability analysis reveals that, in the absence of inertia and thermocapillarity, perturbations grow due to the classical Rayleigh-Plateau instability. Moderate inertia enhances instability, although Rayleigh-Plateau instability remain dominant over inertial instability for high surface tension fluids. The relative influence of gravity and surface tension, represented by the Bond number, tends to stabilize long-wave disturbances (). Thermocapillary stress stabilizes film flow on a cooled cylinder and destabilizes it on a heated one. The Biot number plays a dual role-initially amplifying instability, then reducing it as interfacial temperature gradients diminish. Spatiotemporal analysis uncovers a transition from convective to absolute instability with increasing Marangoni or Reynolds numbers. Lower Bond numbers favor absolute instability, which transitions to convective behavior as Bond number increases. Numerical simulations align well with theoretical predictions, capturing both temporal and spatiotemporal film dynamics under varying physical conditions
Salinity distribution analysis for the region of freshwater influence (RoFI) at the Musi-Banyuasin Estuary, Indonesia
No full textRoFI is a transition zone where fresh water and sea water mix, characterized by water column stratification, with salinity as the key parameter. This study is the first to identify RoFI based on salinity gradients in the Musi–Banyuasin Estuary, aiming to reveal the distribution patterns of salinity and oceanographic parameters that influence RoFI extent. Observations were conducted at 9 stations using CTD, with horizontal and vertical profiles visualized in ODV, and tides and currents analyzed as the primary controllers of RoFI dynamics. The results show that RoFI can be clearly identified through salinity distribution, where the Musi Estuary is characterized by low surface salinity (5 PSU) and water column salinity of 25–30 PSU at high tide, with residual freshwater influence at low tide, while the Banyuasin Estuary is dominated by high salinity (24–28 PSU) throughout the water column, reflecting the dominance of seawater. PCA analysis (80.41%) confirmed that the RoFI area is closely related to tides, currents, and river discharge. However, the limited observation period indicates the need for further season-based studies to understand RoFI dynamics better