High Nutrient Concentrations Research Articles

Application of Isochoric Impregnation: Effects on Microbial and Physicochemical Parameters and Shelf Life of Strawberries Stored Under Refrigeration

This study evaluates the effectiveness of isochoric impregnation during isochoric cold storage in extending the shelf life of strawberries. Strawberries in two different impregnation solutions—(1) sucrose solution and (2) sucrose solution containing calcium chloride (CaCl2) and ascorbic acid (AA)—were first stored in an isochoric chamber at −2 °C/48 MPa for 1 week, followed by refrigeration at 4 °C for 3 weeks. For comparison, strawberries were also immersed in each solution for 1 week at 4 °C then refrigerated at 4 °C for 3 weeks. Additionally, a control group of fresh strawberries was stored at 4 °C for 4 weeks. The quality of the strawberries was assessed at 1-week intervals throughout the storage period. Isochoric cold storage effectively inhibited microbial growth and reduced the weight loss of the strawberries compared to refrigerated storage. Also, isochoric cold storage resulted in strawberries that retained their color attributes, whereas refrigeration led to a significant change in their color attributes. Isochoric impregnated strawberries in the sucrose solution containing CaCl2 and AA showed better mechanical properties and higher nutrient contents (anthocyanins and ascorbic acid) than those impregnated in the sucrose solution, impregnated in the solutions at 4 °C, and refrigerated with no impregnation (control). The results demonstrated that isochoric cold storage in a solution containing sucrose, CaCl₂, and ascorbic acid effectively maintained the quality of the strawberries, as indicated by parameters such as firmness, color retention, and reduced microbial growth. This method extended the strawberries’ shelf life by up to 4 weeks.

Shifts in competition outcomes between two Daphnia species in response to algal phosphorus content

Competition is one of the key drivers of cladoceran community dynamics. Competitive abilities can be measured as the Threshold Food Concentration (TFC), i.e., concentration of food at which population growth rate equals zero. Species with lower TFC should be superior competitors. However, population TFC can vary with environmental conditions. We hypothesized that algal phosphorus (P) content influences TFC and can alter the outcome of competition between large and small-bodied cladocerans. We conducted competition and life table experiments with single clones of large Daphnia magna and small Daphnia longispina to assess how algal P content affected their TFC and competitive interactions. We also conducted computer simulations to further explore competition between the small and large species. Our experiments showed that TFC varied with the algal P content. P limitation increased the TFC of both species, but this increase was more pronounced for the smaller D. longispina. For this reason, D. magna was a superior competitor at low P content, while D.longispina was superior at high P content. We also found that enhanced food abundance gave an additional advantage to the large-bodied D. magna due to higher reproduction potential at high food concentrations.

Assessment of pollution in Alibeykoy Dam Lake (Istanbul, Türkiye) and its influent streams: Phytoplankton composition and heavy metal accumulation.

In this study, the pollution levels of Alibeykoy Dam Lake were assessed by examining phytoplankton distribution, physicochemical parameters, nutrient content, and heavy metal concentrations. Alibeykoy Dam is a critical drinking water source for the Istanbul metropolitan area. Water samples were collected from the lake and six influent streams (Cebeci, Pirincci, Sidan, Bolluca, Gulgen, and Kocaman) in January, February, May, and September of 2021. A total of 36 taxa from seven divisions were identified, including Bacillariophyta (14), Charophyta (2), Chlorophyta (9), Cryptophyta (1), Cyanobacteria (3), Euglenozoa (4), and Miozoa (3). Diatoms were found to be the dominant group in terms of species richness and abundance. The dominant species recorded in each site were as follows: Microcystis aeruginosa in Alibeykoy Dam and Sidan Creek, Cyclotella ocellata in Cebeci and Gulgen Creeks, Scenedesmus sp. in Pirincci Creek, Navicula cryptocephala in Bolluca Creek, and Sphaerocystis planctonica in Kocaman Creek. Mesotrophic and eutrophic phytoplankton species suggested that the lake is nearing eutrophic conditions. This conclusion was further supported by high concentrations of heavy metals and nutrients detected in the water samples. This research is significant because it provides a comprehensive understanding of the ecological status of Alibeykoy Dam Lake, a critical resource for drinking water in Istanbul. The study highlights potential risks associated with eutrophication and heavy metal accumulation by identifying pollution levels and dominant species. These findings are vital for implementing effective water resource management strategies, ensuring the lake's sustainability, and protecting public health. PRACTITIONER POINTS: The pollution rate of Alibeykoy Dam Lake was determined. The presence of mesotrophic and eutrophic species of phytoplankton indicated the lake's trophic structure. The measurements were done to estimate the lake's heavy metal and nutrient contents.

Wheat dust and extracted rapeseed scrap biochar: a comprehensive characterization and assessment of potential utilization in the context of the circular economy

Abstract The current utilization of wheat dust (WD) and hexane-extracted rapeseed scrap (RS) in Central Europe is inefficient and non-ecological. Therefore, it is necessary to identify an appropriate waste treatment that supports the principles of the circular economy. For this reason, the aforementioned wastes were pyrolyzed, resulting in the production of biochars, which are commonly used as absorbents or soil amendments. These biochars were then steam activated, characterized, and evaluated for potential further suitable and sustainable utilization. The structure, porosity, specific surface area, and composition of bound functional groups, nutrients, toxic elements, cation exchange capacity (CEC), and pH were analyzed as important parameters for biochar applications. RS biochar contained high concentrations of nutrients (N 75.9, P 21.5, K 15.1, C 603, Ca 14.3, Mg 8.31, S 5.40 g·kg−1 wt. all). The CEC was remarkably high 87.0 cmol·kg−1 for the RS biochar. The SSA value increased in fivefold in both samples upon activation (11.0 m2·g−1 for WD biochar and 0.8 m2·g−1 for RS biochar). The pore depth increased in accordance with activation temperature. Alkanes, aromatics, and oxygenated groups were detected on the biochars surfaces, yet more evident in WD. WD biochar could be used as an adsorbent for organic pollutants because its structure, surface area, and representation of functional group predict high adsorption efficiency, especially after activation. Raw RS biochar is more suited to utilization as a soil amendment, due to its high concentration of nutrients. These utilizations of biochar support the circular economy, eliminate pollution, improve soil properties, and reduce the need for industrially produced fertilizers and sorbents. Graphical abstract

Assessing the Efficiency of Phragmites australis in Wastewater Treatment as a Natural Approach to Water Quality Improvement

The Oued Zénati, a vital waterway in Algeria, faces severe pollution from urban discharges, hospital wastewater, and agricultural activities, threatening both the ecosystem and public health. This pollution is characterized by high nutrient levels, suspended solids, and fecal contamination indicators, jeopardizing biodiversity and human well-being. To explore natural restoration solutions, this study assessed the purification potential of reeds (Phragmites australis) found in the Oued Zénati riverbed. Water quality was analyzed at three sites: a non-polluted control site (S1), a wastewater discharge area (S2), and a reed-dense area (S3). Results revealed a significant deterioration in water quality at site S2, with high concentrations of nutrients, suspended solids (SS), and fecal contamination indicators. However, a notable improvement in water quality was observed at site S3, downstream of the reed-dense area, with reductions in fecal coliforms (68.5%), fecal streptococci (92.3%), and phosphates (40.3%), and increased levels of dissolved oxygen (DO). These findings suggest that phytoremediation using P. australis could offer a cost-effective, sustainable, and eco-friendly solution for restoring the Oued Zénati. This study recommends establishing phragmifiltration stations, developing artificial wetlands, and enhancing sanitation systems, including hospital wastewater treatment. Public awareness campaigns promoting water and environmental protection are crucial for long-term success. This phytoremediation approach offers economic, ecological, and aesthetic advantages over conventional wastewater treatment techniques.

ИЗУЧЕНИЕ ЭФФЕКТИВНОСТИ ПРИМЕНЕНИЯ ИННОВАЦИОННЫХ ВИДОВ БИОКОРРЕКТОРОВ ДЛЯ УПРАВЛЕНИЯ КАЧЕСТВОМ И НУТРИЕНТНЫМ СОСТАВОМ МИКРОЗЕЛЕНИ КАК ИСТОЧНИКА ПИЩЕВЫХ ФУНКЦИОНАЛЬНЫХ ИНГРЕДИЕНТОВ

The aim of the study is to develop mechanisms for controlling the activity of the photosynthesis process of individual types of microgreens during vegetation in a closed system of an urban-type phytotron to obtain the maximum possible, genetically determined content of essential phytonutrients, which can subsequently be used as a source of functional ingredients in the diet for the prevention of alimentary diseases. The results of the development of the main elements of biotechnology for growing microgreens in an urban-type phytotron are presented. The obtained results characterize the efficiency of regulation of the activity of metabolic processes occurring during the cultivation of microgreens in the conditions of an urban-type phytotron by controlling individual elements of the biotechnological process – optimization of seed germination technology, intensity and spectrum of light illumination, differentiation of daily temperature and light conditions, use of individual and/or complex bioinducers to control the quality and nutrient composition of microgreens as a source of food functional ingredients for healthy nutrition.The comparative efficiency of treating the studied crops with inorganic phytoinducers 1-germatranol and 1-ethoxysilatrane was established in comparison with the use of microbiological synthesis preparations Nikfan, Azotovit and Super mycorrhiza. The highest indicators for productivity, total content of chlorophyll, carotenoids, phenolic substances, vitamin C and total antioxidant activity were found in samples treated with inorganic preparations 1-germatranol, 1-ethoxysilatrane and organic preparation Super mycorrhiza. It is recommended to use environmentally friendly microgreens grown using optimized technology with a given composition of phytochemical compounds and a high content of functional nutrients for constructing diets for functional and personalized nutrition.

Analisis Pemasaran Maggot BSF (Black Soldier Fly) Desa Bojo

This study aims to analyze the marketing system of maggot bsf in Bojo Village. Based on the results of observations and interviews in Bojo Village, the main problem was found, namely household waste. The garbage was thrown out of place, the garbage was found scattered on the beach and close to residential areas. The waste that is wasted includes organic waste from household waste. Organic waste can cause environmental problems such as air and soil pollution and cause various negative impacts on public health. A solution that can be done by village communities is maggot cultivation from Black Soldier Fly (BSF) flies, as an effective and easy way to manage organic waste. By cultivating maggot for organic waste, we can create a high-value resource that can have a positive impact on the environment and the economy of the village community. Maggot cultivation aims to decompose organic matter left over from household food consumption. Able to digest organic waste quickly so that it helps reduce the volume of organic waste. In addition, maggots are also able to prevent uncontrolled accumulation of waste. In fact, casgot which is the result of the decomposition of waste carried out by maggot can produce high-quality organic fertilizer that can increase soil fertility. Maggot has a high nutrient content that helps local agriculture. Maggot cultivation can also be a new business opportunity for village communities because it can be sold as animal feed. It has an impact on increasing the income of the local community.

Effect of Different Stimulation Methods on the Activation and Metabolic Performance of Microbial Community to Enhance Heavy Oil Recovery

Microbial enhanced oil recovery (MEOR) is an economical and efficient tertiary recovery technology that can be used to increase the recovery of heavy oil reservoirs after steam thermal operation. However, the introduction of high-pressure steam with a temperature as high as 370 °C during thermal recovery can disrupt the indigenous microbial flora of oil reservoirs. Consequently, the effective activation of the functional microbial flora after steam thermal operation is crucial for heavy oil recovery. As such, we investigated the effects of different activation methods on oil viscosity reduction, biogas production, microbial community structure, and microbial metabolic performance. The highest viscosity reduction (61.59%), methane content (25.96%), and asphaltene degradation rates were achieved when low/high content of organic nutrients were alternately added in group L-H. The results of the FT-ICR MS analysis showed that the addition of a high content of organic nutrients promoted the degradation of N1 classes, and the degree of aromaticity of N1O2 class compounds (DBE = 10) was reduced. The analysis of the microbial community showed that function bacteria, such as Firmicutes and Synergistetes, were effectively activated by the alternate addition of nutrients, which could prevent the accumulated fatty acids and accelerate the asphaltene degradation and methane production through the syntrophic relationship between syntrophic bacteria and methanogens. Thus, the alternate addition of nutrients has potential application for enhancing heavy oil recovery by simultaneously reducing heavy oil viscosity and improving methane production.

Macrophytes and Phytoplankton, Two Primary Antithetical Producers in Degraded Water Systems

One year of monthly sampling in some lagoons of the Po Delta and a pond in the Comacchio Valleys helped fill a gap in the knowledge of the primary producers of these degraded environments, focusing on the competition between macrophytes and phytoplankton. Key water column and surface sediment parameters showed a strong association with the different primary producers, explaining the main factors influencing the dominance of one group over the other. Phytoplankton, recorded as Chlorophyll-a and Phaeophytin-a, and Chlorophyceae among the macrophytes, dominated in conditions of high water turbidity and elevated nutrient concentrations. In contrast, macrophytes, particularly Rhodophyceae, their abundance, total biomass, and number of taxa. prevailed in clear, oxygenated waters. Under optimal conditions, sensitive macroalgae and aquatic angiosperms were also present. Additionally, the current list of macroalgal taxa has been updated, highlighting the dominance of some nonindigenous species (NIS) that had not been recorded before the 2000s. Specifically, Gracilaria vermiculophylla and Ulva australis, native to the North West Pacific (Japan, Korea, China, and Vietnam) and to South Australia, as well as the Indo-West Pacific (India, South Africa, Japan, and Korea), respectively, are now the most frequent and abundant taxa in these lagoons.

Effect of Different Sources and Levels of Zinc on the Nutrient Content, Uptake and Fertility Status of Wheat

Indian farmers face challenges in wheat production due to poor soil nutrients and imbalanced fertilizer use, making zinc-supplemented fertilizers vital for boosting productivity. Wheat (Triticum aestivum L.) is a vital global food crop, rich in carbohydrates, protein, and essential nutrients, with India being a major producer, although many regions face significant zinc deficiency in their soils. A field study was conducted during Rabi 2021-2022 at Wheat Research Unit, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. The experimental soil collected from the wheat research unit field was slightly alkaline in reaction, medium in organic carbon, moderately calcareous, low in available N, medium in available P, remarkably high in available K, marginal in available S, and sufficient in micronutrients but deficient in Zn. The nine treatments T1 to T9 are applied in the plots in Randomized Block Design with three replications. The higher nutrient content and N, P, K, S, Zn, Fe, Cu, and Mn uptake was recorded with the soil application of RDF + soil application of ZnSO4 @ 30 kg ha-1. It is concluded that the soil application of ZnSO4 @ 30 kg ha-1 along with a recommended dose of fertilizer (RDF) at the time of sowing recorded the highest nutrient content, nutrient uptake and improvement in soil fertility.

Effect of Land Use Types and Slope on Selected Soil Physicochemical Properties in Bubisa Watershed, Adea Berga District, Central Ethiopia

Soil physicochemical properties can be affected by different land use type in Ethiopia. The nutrient content of soil in the three sites was varied based on; soil management systems, organic inputs and other factors. Cognizant of this fact, research was conducted in Bubisa Watershed to evaluate the effect of different land use types and slope on selected physicochemical properties of soil. Accordingly, lands such as; crop, grazing and forest land were nominated and twenty seven (27) core and composite soil samples were collected from 0-20 cm layers. Soil analysis was done and the highest (1.29 g cm<sup>-3</sup>) bulk density was recorded on the upper slope of crop land and lower (0.99 g cm<sup>-3</sup>) on the lower slope of forest land. Total porosity and Available water holding capacity were high (60.02%; 172 mm/m) in forest land and lower (49.56%); 152 mm/m) in crop land respectively. Soil pH was high in forest land and low in crop land soils. The result of soil organic carbon and total nitrogen were also high (4.51%; 0.22%) in forest land and low (1.4; 0.15) crop land soils, respectively. Moreover, CEC and basic cations varied across the three sites and high in forest land and low in crop land in the study watershed. Based on the results, it was concluded that forest has high concentration of soil nutrients except bulk density than crop land. As recommendation, studies should be expanded to provide more conclusive recommendation to have qualified; productive soils and estimate the effect of land use types and slope on soil properties for sustainable agricultural productivity.

Aquaculture Wastewater Treatment by Constructed Wetlands Planted with Anthurium Plants (Anthurium andraeanum)

Aquaculture wastewater often has high content of organic matter and nutrients (nitrogen, phosphorus). Along with the rapid development of the aquaculture industry is the problem of water pollution, eutrophication... because of untreated wastewater. Among current wastewater treatment methods, constructed wetland technology is an environmentally friendly wastewater treatment solution, providing high treatment efficiency and low cost. In this study, constructed wetland systems planted with anthurium plants (Anthurium andraeanum) at laboratory-scale were established to treat shrimp farming wastewater in Quang Ninh. The results showed that after 15 experimental days, the wetland system planted with anthurium plants on gravel and coconut fiber materials had organic matter (COD) removal efficiency, ammonium (NH4+-N) and phosphate (PO43--P) removal efficiency of 87.5%, 76% and 44.1%, respectively. The wetland system planted with anthurium plants on gravel had organic matter (COD) removal efficiency, NH4+-N and PO43--P removal efficiency of 75.7%, 46.7%, and 40.6%, respectively. Meanwhile, the COD removal efficiency, NH4+-N and PO43--P removal efficiencies in the control system were only 15.8%, 12.6% and 19.4%, respectively. The research results show the ability of constructed wetland systems planted with anthurium plants to treat aquaculture wastewater.

Changes in Antioxidant and Photosynthetic Capacity in Rice Under Different Substrates.

Against the backdrop of a changing global climate, the soil environment may undergo significant changes, directly affecting agricultural productivity and exacerbating global food security issues. Three different substrates were set up in this study, namely, S (high sand and low nutrient content), T (medium sand and medium nutrient content), and TT (low sand and high nutrient content). The results showed that the root/shoot ratio increased as the sand content increased (nutrient content decreased). Rice in different substrates had various degrees of dependence on antioxidant enzymes and antioxidants. For example, seedlings in TT treatment may depend more on ascorbic acid (AsA) compared to T. In addition, compared with S and T, the photosynthetic activity of rice in the optimized substrate (TT) was the highest; the net photosynthetic rate (Pn) of TT seedlings was significantly higher than that of T. This study also detected that the change in substrates affected the gas exchange parameters of rice leaves. The transpiration rate (Tr) and stomatal conductance (Gs) of the TT treatment were higher than those of the T treatment. The results of this study may provide a scientific basis for formulating agricultural management strategies.

Root-associated functional microbiome endemism facilitates heavy metal resilience and nutrient poor adaptation in native plants under serpentine driven edaphic challenges.

Serpentine soils are characterized by high concentrations of heavy metals (HMs) and limited essential nutrients with remarkable endemic plant diversity, yet the mechanisms enabling plant adaptation to thrive in such harsh environments remain largely unknown. Full-length 16S rRNA amplicon sequencing, coupled with physiological and functional assays, was used to explore root-associated bacterial community composition and their metabolic and ecological functions. The results revealed that serpentine plant species exhibited significantly higher metal transfer factor values compared to non-serpentine plant species, particularly evident in Bidens pilosa, Miscanthus floridulus, and Leucaena leucocephala. The serpentine root-associated microbes showed a higher utilization of carboxylic acid, whereas carbohydrate utilization was higher in the non-serpentine site. Zymomonas mobilis and Flavabacterium sp. exhibited high resistance to heavy metal concentrations, showing greater adaptability, while, Staphylococcus carnosus showed sensitivity to HMs, showing limited adaptability. Moreover, Ni, Cr, and Co resistance genes were found, while nitrogen and phosphorous metabolism genes were less abundant in the serpentine site compared to the non-serpentine site. Furthermore, Flavobacterium sp. had a strong positive relationship with Cd and Cu, Zymomonas mobilis with Ni, and Cr, Streptomyces sp. with Co, and Staphylococcus carnosus with N and P cycling. These findings underscore critical role of root-associated bacterial communities and distinctive soil conditions of serpentine habitats in fostering ecological adaptation of native plant species to the challenges posed by HMs and nutrient deficiencies.

CO2 Fertilisation Counteracts the Negative Effect of Poor Water Quality on the Growth and Photosynthesis of a Great Barrier Reef Coralline Alga

ABSTRACTThe global problem of ocean acidification and localised decline in water quality are major threats to coral reefs worldwide. This study examined the individual and interactive impacts of global and local stressors by investigating the effects of increased seawater pCO2, elevated nutrient concentrations and reduced light levels on linear growth and metabolic rates of the common branching crustose coralline alga Lithophyllum cf. pygmaeum. We found complex interactions between factors on algal growth and photosynthetic rates, but overall, growth was significantly enhanced by pCO2 enrichment under all light and nutrient combinations. This is the first study to report a positive growth response in coralline algae to elevated pCO2 using linear extension methods. In contrast, the combination of reduced light levels and high nutrient concentrations simulating poor water quality conditions reduced algal growth rates by up to 67% (compared to individuals exposed to high light, low nutrients and elevated pCO2). Decreased light levels reduced linear growth, Pgross and Pnet rates by 33%, 18% and 24%, respectively, highlighting the critical role of light in coralline algal physiology. We suggest that poor water quality may counteract any CO2 fertilisation effect under ocean acidification conditions on the growth of coralline algae, and this has implications for coral reef conservation as it emphasises the importance of improving water quality to maintaining coral reef functions. These results further highlight the need for multifactorial experiments to better understand the interplay between global and local processes on coralline algae growth.

Characterization of Parthenium (Parthenium hysterophorus L.) Compost for Plant Nutrient Contents at Ginir District of Bale Zone, South-Eastern Ethiopia

Parthenium (Parthenium hysterophorus L.) characterization in the southeast of Ethiopia, in the Oromia Region, the compost for Major Plant Nutrient Contents experiment was carried out in the Ginir District of the Bale Zone. As a result, the purpose of this research was to evaluate the quality and nutrient content of compost made from parthenium combined with wheat byproduct and farmyard manure. Before they began to bloom, the parthenium plants were harvested and cut into smaller pieces. As a result, parthenium compost was made using three different methods, including parthenium biomass plus farmyard manure, parthenium biomass plus crop residue, and parthenium biomass plus both farmyard manure and crop residue. Important chemical characteristics like pH, EC, OC, TN, available P, CEC, and exchangeable bases (Ca, Mg, K, and Na) and micronutrients (Fe, Mn, Cu, and Zn) were examined using standard practice laboratory techniques. The compost had high plant nutrients and significantly varied among the three Parthenium compost preparation techniques, according to the results of the final laboratory analysis of the prepared and harvested Parthenium compost. As a result, Parthenium compost provides multiple benefits, including high nutrient content, weed control, and the general environmental friendliness of using organic fertilizers.

Diatom Communities in the Littoral Sediments of the Robert Island`s Lakes, South Shetland Islands, Antarctica

The study area is situated at Robert Island, which is located in the South Shetland Islands in the northwest of the Antarctic Peninsula. The diatom samples were taken as part of the Turkish Antarctic Expedition (TAE-II) which took place between March and April 2018. The samples were collected from the surface of sediments (c. 5 cm) at a depth of approximately 20 cm, 50–100 cm from the littoral zones of an inland glacial lake (L1) and three coastal lakes (L2, L3 and L4) situated on glacier-free area on Robert Island. The main objective of this study was to reveal the diversity and the abundance of diatom communities in the littoral sediments of the lakes on Robert Island. The lakes are shallow and oligotrophic freshwater lakes, although the coastal lagoons have a high conductivity and nutrient concentration. Twenty-six diatom taxa belonging to Achnanthes (1), Fragilaria (1), Frustulia (1), Gomphonema (1), Halamphora (1), Hantzschia (1), Hippodonta (1), Humidophila (2), Luticola (3), Melosira (1), Nitzschia (4), Pinnularia (3), Planothidium (2), Psammothidium (2), Stauroneis (1) and Stephanopterobia (1) were identified in the samples from these lakes. The coastal lake L2 showed the highest richness of diatom communities among the in studied lakes, with 21 identified taxa.

Preparation of biscuits from Manihot esculenta leaf flour

The Manihot esculenta (cassava) has an important representation, as it has a high nutrient content and versatility in technological use. The present study aimed to produce cassava leaf flour and use it in the production of biscuits. Cassava leaves were washed in and sanitized. Subsequently, the leaves were placed inside a solar dryer, previously cleaned and sanitized, and exposed to sunlight for 2 days (~30 h). After drying, they were ground in a domestic blender, with standardization of the granulometry by passing through a 14-mesh sieve, and the flour obtained was stored in an airtight container. Three preparation of the biscuits consisted of three formulations with different concentrations of cassava leaf flour: Standard (P, 0%), F1 (5%) and F2 (10%); replacing the proportion of flours. The analyses of cassava flour and biscuits were based on instrumental color, pH and total titratable acidity. The instrumental color parameters for cassava leaf flour were: L* 42.11 ± 0.05, a* −7.88 ± 0.01, b* 21.471 ± 0.48, C* 22.78 ± 0.45 and °h 110.25 ± 0.40, indicative of the presence of yellow and green pigments, in addition to low luminosity. The pH was 5.62 ± 0.40, characteristic of low acidity. The biscuits showed statistical difference between them (p < 0.05) in all color parameters. The pH content of the biscuits ranged from 6.39 to 6.65, with no significant difference (p > 0.05). Regarding titratable acidity, it did not vary significantly (p > 0.05): 0.03 to 0.06 g citric acid 100 g−1. This is a concise presentation of all the relevant points of the study. Biscuits are low-acid foods due to their low acidity content.

The Influence of Lipase Enzyme Level and Ca(OH)2 Usage in the Production of Protected Lemuru Fish Oil Supplement on the Texture, Nutrient Content, and Fatty Acid Value of the Product

The scarcity of feed energy source to ruminant can be anticipated by adding oil to the feed. However, the effect of adding oil to the feed more than 7% will reduce the activity of fiber-degrading microbes because fat is toxic. In addition, fat in the feed will easily undergo biohydrogenation by rumen microbes so that it will reduce its function. Making fat protection feed using lemuru fish oil with a combination of lipase enzymes and Ca(OH)2 can be a solution because it aims to protect fat from biohydrogenation in the rumen. The experiment used a completely randomized design method with a 3×2 factorial pattern with factors 1) lipase enzyme (0%, 0.5%, and 1%) and factor 2) Ca(OH)2 (20% and 25%). The product results obtained showed that the product quality was in good condition with the product hardness criteria at number 4 (hard). Analysis of variance showed no significant effect on interaction,enzyme factor and Ca(OH)2 factor (P>0.05) on DM, OM, CF and acid number where the combination of L1K20 treatment (1% enzyme and 20% Ca(OH)2) produced the highest DM content of 90.25±1.12%; OM 81.98±1.35%; CF 14.62±0.53%; and the lowest acid number of 0.54±.0.06 mg KOH/g sample. The conclusion that can be given is that the use of a combination of 1% lipase enzyme and 20% Ca(OH)2 in fat protection products produces good quality products in terms of product hardness, high nutrient content and low acid number according to the standard fatty acid number below 1 mg KOH/g sample.

Characterization of biochar produced from paperboard sludge: A sustainable approach for waste management and resource recovery

The pulp and paperboard industry are a significant industrial sector that consumes large quantities of fresh water and generates substantial volumes of wastewater. Treating this wastewater produces a considerable amount of sludge, which poses serious environmental challenges. This study proposes a sustainable solution by converting paperboard sludge (PBS) into biochar through slow pyrolysis at temperatures ?00°C, offering an alternative approach to waste management and resource conservation. The physicochemical analysis of paperboard sludge biochar (PBSB) revealed a neutral pH of 7.49, electrical conductivity of 0.09 dS m-1, an organic carbon content of 38.12%, and a calcium carbonate (CaCO3) content of 24.5%. Proximate analysis of PBSB revealed an increased fixed carbon content of 10.27 %, total organic carbon (TOC) of 7.13%, and reduced volatile matter and moisture levels. Micronutrients viz., iron (Fe) (5.06 mg L-1), Manganese (Mn) (419.3 mg L-1), Copper (Cu) (26.3 mg L-1), and Zinc (Zn) (66.1 mg L-1), were also observed in PBSB. FTIR analysis identified various carbon-containing functional groups, including C-Cl, C-N, C-C, H-C=O, C-H, and -C?C-H, indicating substantial chemical transformations during pyrolysis. Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) analysis revealed that PBSB consists of fine particles with a coarse, fluffy, spongy, porous structure, making it ideal for water adsorption. Elemental analysis through x-ray diffraction (XRD) showed high carbon and oxygen content and significant amounts of aluminosilicates, carbonates, and nutrients like phosphorus and potassium, suggesting PBSB as a potential slow-release fertilizer. This research highlights the potential of biochar derived from paperboard waste as a sustainable solution for effective waste management and resource recovery.