Chemical Extraction Techniques Research Articles

Geochemical fractionation, bioavailability, and ascertaining ecological risk of phosphorus in surface and core sediments of mangroves, western coast of India.

Phosphorus (P), a crucial macronutrient, is essential in the maintenance of ecosystem productivity and the biogeochemical processes of other biogenic substances found in marine settings. The aim of the present study is to quantify the different geochemical fractions, bioavailability, and ecological risk of phosphorus in surface and core sediment of mangroves, Gulf of Kachchh (GoK). To better understand the P dynamics, sequential chemical extraction techniques were used to study sediment P pool distribution such as exchangeable P; Fe-bound P; authigenic P; detrital P; and organic P. The total sedimentary P ranged from 539.51 to 7217.24mg/kg in pre-monsoon and 487.04 to 7180.26mg/kg in post-monsoon, and was primarily composed of inorganic P. Authigenic P and Fe-bound P were the dominant fractions of P in surface and core sediments, exhibiting a significant long-term P reservoir. Sources such as riverine inputs, industrial and sewage discharge, aquaculture farms, and seaport operations all have an impact on the P dynamics in GoK. Furthermore, organic matter, pH, ORP, and diagenetic processes in sedimentary environment have influenced P retention and release. FeBD:Fe-P ratio indicates the presence of Fe matrices, having strong adsorption potential for P, with the availability of a surplus of Fe(III) (oxy)hydroxides serving as a significant P pool, governing the P dynamics. The P enrichment index (PEI) showed that sediments were highly impacted by anthropogenic P and could cause a high ecological risk. Bioavailable phosphorus (BAP) suggests the availability of an ample amount of bioavailable P fractions (average of 49.70% post-monsoon and 44.64% post-monsoon) in surface sediments. Sites 3, 13, 14, 20, 21, and 26 exhibited considerably higher BAP. Core 1 comprised significantly higher BAP (60.52%). Thus, sediments of GoK could act as a source of P to the overlying water if released from sediments.

Potential Role and Mechanism of Mulberry Extract in Immune Modulation: Focus on Chemical Compositions, Mechanistic Insights, and Extraction Techniques.

Mulberry is a rapidly growing plant that thrives in diverse climatic, topographical, and soil types, spanning temperature and temperate countries. Mulberry plants are valued as functional foods for their abundant chemical composition, serving as a significant reservoir of bioactive compounds like proteins, polysaccharides, phenolics, and flavonoids. Moreover, these compounds displayed potent antioxidant activity by scavenging free radicals, inhibiting reactive oxygen species generation, and restoring elevated nitric oxide production induced by LPS stimulation through the downregulation of inducible NO synthase expression. Active components like oxyresveratrol found in Morus demonstrated anti-inflammatory effects by inhibiting leukocyte migration through the MEK/ERK signaling pathway. Gallic and chlorogenic acids in mulberry leaves (ML) powder-modulated TNF, IL-6, and IRS1 proteins, improving various inflammatory conditions by immune system modulation. As we delve deeper into understanding its anti-inflammatory potential and how it works therapeutically, it is crucial to refine the extraction process to enhance the effectiveness of its bioactive elements. Recent advancements in extraction techniques, such as solid-liquid extraction, pressurized liquid extraction, superficial fluid extraction, microwave-assisted extraction, and ultrasonic-assisted extraction, are being explored. Among the extraction methods tested, including Soxhlet extraction, maceration, and ultrasound-assisted extraction (UAE), UAE demonstrated superior efficiency in extracting bioactive compounds from mulberry leaves. Overall, this comprehensive review sheds light on the potential of mulberry as a natural immunomodulatory agent and provides insights into its mechanisms of action for future research and therapeutic applications.

Bioactivities of Jojoba Oil Beyond Skincare.

Jojoba oil, which is extracted from jojoba plant seeds that are native to North America, possesses a unique molecular structure and is distinct from other oils. Unlike typical oils, which mostly contain triglycerides, jojoba oil is composed of long monounsaturated esters, affording it exceptional properties and is valuable across cosmetics, chemicals, and pharmaceuticals. While jojoba oil is prevalent in beauty and skincare today, its seeds and oil have ancient roots in folk medicine, used for treating skin and scalp issues, wounds, sore throats, obesity, and even cancer, while enhancing immunity and fostering hair growth. Modern research underscores jojoba oil's pharmacological versatility, demonstrating antioxidant, antidiabetic, anti-acne, anti-inflammatory, antipyretic, and antibacterial properties. Notably, there has been a surge in its utilization in pharmaceuticals, particularly in topical, transdermal, and parenteral formulations. This review provides a comprehensive overview of jojoba oil, encompassing its chemical composition, extraction techniques, health advantages, and pharmaceutical application developments.

Bioavailability of Metals in the Biosphere

In some areas, soil, sediment, water, and organic materials may exhibit elevated concentrations of various metals. Under certain conditions, these metals can take on most bioavailable forms. To assess the impacts and potential risks associated with elevated element concentrations, understanding the fraction of whole elements in water, sediment, and soil which are bioavailable is very important. The study aims to examine these conditions to accurately assess potential environmental impacts. For the study, searches were carried out using the keywords "bioavailability", "metal" and "environment" in various combinations in English. The search was limited to articles published open access in NCBI or PubMed, Scopus, and Google Scholar. The language of the manuscript was not restricted. The complex interactions of these diverse factors highlight the difficulty of assessing and understanding the bioavailability of metals in different environmental matrices. The study identified key factors affecting the bioavailability of the metal. These factors can change over time and among different microorganisms, plants, and animals. Research involving field and laboratory studies conducted at specific locations in soil, sediment, and flora using selective chemical extraction techniques is critical to a detailed understanding of the complex ecological processes associated with the bioavailability of metals to organisms.

Shrimp Waste Upcycling: Unveiling the Potential of Polysaccharides, Proteins, Carotenoids, and Fatty Acids with Emphasis on Extraction Techniques and Bioactive Properties.

Shrimp processing generates substantial waste, which is rich in valuable components such as polysaccharides, proteins, carotenoids, and fatty acids. This review provides a comprehensive overview of the valorization of shrimp waste, mainly shrimp shells, focusing on extraction methods, bioactivities, and potential applications of these bioactive compounds. Various extraction techniques, including chemical extraction, microbial fermentation, enzyme-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, and pressurized techniques are discussed, highlighting their efficacy in isolating polysaccharides, proteins, carotenoids, and fatty acids from shrimp waste. Additionally, the bioactivities associated with these compounds, such as antioxidant, antimicrobial, anti-inflammatory, and antitumor properties, among others, are elucidated, underscoring their potential in pharmaceutical, nutraceutical, and cosmeceutical applications. Furthermore, the review explores current and potential utilization avenues for these bioactive compounds, emphasizing the importance of sustainable resource management and circular economy principles in maximizing the value of shrimp waste. Overall, this review paper aims to provide insights into the multifaceted aspects of shrimp waste valorization, offering valuable information for researchers, industries, and policymakers interested in sustainable resource utilization and waste-management strategies.

Novel positioning of Olea europaea L. (Olive) from farm to pharma indexed in pharmacopeia

The current study explores the transformative journey of L. (Olive) from its traditional role in random traditional medicine to its current positioning in pharmacopeia as a pharmaceutical preparation with defined dosage and indications. The comprehensive examination covers botanical and chemical profiles, traditional uses, pharmacological activities, extraction techniques, quality control, regulatory status, clinical studies, and future directions. Various analytical methods, including spectroscopic and chromatographic approaches, are discussed for quality evaluation and detection of adulteration. Additionally, the regulatory landscape, particularly within the European Union, is outlined, emphasizing the importance of accurate labeling and geographical origin disclosure. The regulatory status of L. varies across regions, ranging from restrictions due to safety concerns to inclusion in pharmacopeias as traditional herbal medicine or pharmaceutical preparations. A pivotal development highlighted is the incorporation of Olive into Egyptian pharmacopeia, signifying a significant shift towards evidence-based therapy and reinforcing its acceptance in mainstream healthcare.

Fractionation and Lability of Phosphorus Species in Cottonseed Meal-Derived Biochars as Influenced by Pyrolysis Temperature.

Defatted cottonseed meal (CSM), the residue of cottonseeds after oil extraction, is a major byproduct of the cotton industry. Converting CSM to biochar and utilizing the goods in agricultural and environmental applications may be a value-added, sustainable approach to recycling this byproduct. In this study, raw CSM was transformed into biochar via complete batch slow pyrolysis at 300, 350, 400, 450, 500, 550, and 600 °C. Thermochemical transformation of phosphorus (P) in CSM during pyrolysis was explored. Fractionation, lability, and potential bioavailability of total P (TP) in CSM-derived biochars were evaluated using sequential and batch chemical extraction techniques. The recovery of feed P in biochar was nearly 100% at ≤550 °C and was reduced to <88% at 600 °C. During pyrolysis, the organic P (OP) molecules predominant in CSM were transformed into inorganic P (IP) forms, first to polyphosphates and subsequently to orthophosphates as promoted by a higher pyrolysis temperature. Conversion to biochar greatly reduced the mobility, lability, and bioavailability of TP in CSM. The biochar TP consisted of 9.3-17.9% of readily labile (water-extractable) P, 10.3-24.1% of generally labile (sequentially NaHCO3-extractable) P, 0.5-2.8% of moderately labile (sequentially NaOH-extractable) P, 17.0-53.8% of low labile (sequentially HCl-extractable) P, and 17.8-47.5% of residual (unextractable) P. Mehlich-3 and 1 M HCl were effective batch extraction reagents for estimating the "readily to mid-term" available and the "overall" available P pools of CSM-derived biochars, respectively. The biochar generated at 450 °C exhibited the lowest proportions of readily labile P and residual P compounds, suggesting 450 °C as the optimal pyrolysis temperature to convert CSM to biochar with maximal P bioavailability and minimal runoff risk.

A Descriptive Analysis of the Nutraceutical Constituents, Extraction Techniques, and Possible Health Benefits of Tamarind

Background: Tamarind is a multifunctional tree, with nearly every portion having significant nutritional or therapeutic use. The fruit, which produces acidic pulp, is the most valuable and often utilized portion. Objective: The aim of this paper is to discuss the distribution, habitat, chemical constituents and extraction techniques of tamarind. Method: This study reviews the chemical constituents, health benefits and extraction techniques of tamarind. Databases such as PubMed, Scopus, Science Direct, and Google Scholar were used to search articles from 1990 to 2022. The key search terms included tamarind, phytoconstituents extraction and anti-nutritional factor. Research studies also included similar plant parts extracted from similar solvents which were considered in this review. Results: According to our observations, Tamarindus indica is a crucial plant with significant pharmacological properties. It is extensively used as a conventional medicine to treat a variety of disorders; however, its active ingredients require further investigation for future drug development and pharmacological activity. Tamarind contains a diverse range of bioactive compounds, including polyphenols, flavonoids, alkaloids, vitamins, and minerals, which have been associated with various health-promoting properties. The study examines different extraction methods used to isolate tamarind's bioactive constituents, such as solvent extraction, supercritical fluid extraction (SFE), and microwave-assisted extraction (MAE). Furthermore, the research highlights the potential health benefits of tamarind, including antioxidant activity, anti-inflammatory effects, gastrointestinal support, cardiovascular benefits, and antimicrobial properties. Discussion: Tamarind includes citric acid, linoleic acid, volatile oils, vitamin C, potassium, Camp sterol, -amyrin, Tannins, saponins, and glycosides as a result of this. It has several pharmacological properties such as reducing swelling, preventing oxidation, hypolipidemic, weight loss, antibacterial, hepatoprotective, anthelmintic, and painkiller properties. These properties will assist to generate interest in Tamarind and develop novel preparations with more medicinal and commercial potential. The findings indicate that tamarind holds significant promise as a natural resource for developing functional foods, nutraceuticals, and pharmaceuticals with potential positive impacts on human health.

Chitosan and Its Derivatives: Preparation and Antibacterial Properties.

This comprehensive review illuminates the various methods of chitosan extraction, its antibacterial properties, and its multifarious applications in diverse sectors. We delve into chemical, physical, biological, hybrid, and green extraction techniques, each of which presents unique advantages and disadvantages. The choice of method is dictated by multiple variables, including the desired properties of chitosan, resource availability, cost, and environmental footprint. We explore the intricate relationship between chitosan's antibacterial activity and its properties, such as cationic density, molecular weight, water solubility, and pH. Furthermore, we spotlight the burgeoning applications of chitosan-based materials like films, nanoparticles, nonwoven materials, and hydrogels across the food, biomedical, and agricultural sectors. The review concludes by highlighting the promising future of chitosan, underpinned by technological advancements and growing sustainability consciousness. However, the critical challenges of optimizing chitosan's production for sustainability and efficiency remain to be tackled.

Synthesis of crystalline nanocellulose and its effect on the mechanical properties of E-glass fiber/epoxy composite for prosthetic shank applications

Prosthetic shank is one of the prominent parts of prosthetic leg that transfers load from prosthetic socket to the foot section. Nowadays, it is common to use composite materials for prosthetics and orthotics applications. This research aims at synthesis and characterization of properties of crystalline nanocellulose (CNC) powder and investigating its effect on the mechanical and physical properties of E-glass fiber - epoxy composite for prosthetic shank applications. Different properties including tensile, impact, flexural, water absorption, thermographic, density and surface morphology of a hybrid composite are investigated. The research further targets to test the suitability of developed composite material for prosthetic shank applications. Extraction of CNC powder is performed using chemical extraction technique which involves alkali treatment, delignification, bleaching and acid hydrolysis. Crystallinity of CNC particles is determined at 2θ values of 19.89°, 44.04°, 64.34° and 77.51°. Crystallite size of these powders is found to be 13 nm from XRD analysis. Thermal properties of CNCs are examined using thermographic analysis and the result reveals a three-stage decomposition of CNC powders in temperature ranges. The results also reveal that addition of CNC powder enhances the overall performance of the composite, and composite specimen with 8wt% CNC powder shows superior mechanical and physical properties. Further, selected composite is modeled for the prosthetic shank application using commercial finite element software, ANSYS 2022, and maximum equivalent von Mise’s stress of 0.82598 MPa and deformation of 0.054065 mm are obtained Based on the overall findings and analysis, it is highly recommended to develop and use hybrid E-glass fiber – CNC - epoxy composite as a substitute material for prosthetic shank applications.

Optimization of the Two‐ and Three‐Dimensional Characterization of Rare Earth‐Traced Deoxidation Products

Tracing by means of the light rare earths (REs), particularly La and Ce, is a state‐of‐the‐art method used to track deoxidation products during the steelmaking process. Traced heterogeneous multiphase inclusions are analyzed using scanning electron microscopy with energy‐dispersive spectroscopy (SEM/EDS) to perform a 2D characterization. The sequential chemical extraction technique is implemented for a 3D investigation to determine traced particles’ actual sizes and shapes. The automated SEM/EDS measurement must be optimized since RE oxides appear brighter in the backscattered electron images due to their high atomic numbers. Therefore, two grayscales are implemented for the detection of RE‐containing multiphase inclusions. Within this technique, individual RE‐traced heterogeneous nonmetallic inclusions (NMIs) are counted as separate particles. Thus, the measured NMIs must be recombined, which is achieved using a self‐developed MATLAB tool. The extracted particles are also analyzed by automated and manual SEM/EDS measurements to determine the 3D morphologies and sizes of traced NMIs.

Isolation of Antimicrobial Peptides (AMPs) From Different Sources: A Review

Antimicrobial peptides (AMPs) are small peptide molecules produced by a wide range of species, from bacteria to higher vertebrates, as a part of the innate immune system. These naturally produced peptides fight against intrusive microbes like viruses, bacteria, and fungi. AMPs are produced in various body parts by different organisms, such as skin secretion of amphibians; leaf, stem, fruits, or whole parts of plants; glandular secretion of mammals; the venom of reptiles and arthropods, etc. Due to this source variation, there is no universal method for the isolation, i.e., extraction and purification of the AMPs. Therefore, several techniques have been established to extract and purify these natural peptides from various sources. Generally, solid-phase extraction and chemical extraction techniques are the most common methods used for the extraction of AMPs. For purification and identification purposes, chromatography, gel electrophoresis, filtration, Edman degradation, circular dichroism, mass spectrometry, etc. are mainly adopted. In this review, we provide a brief discussion on the isolation process of AMPs based on their sources. This study would be helpful in isolating newer AMPs that could be used as potential antimicrobial agents. Bangladesh Pharmaceutical Journal 26(1): 99-111, 2023 (January)

Improved phosphorus availability and reduced degree of phosphorus saturation by biochar-blended organic fertilizer addition to agricultural field soils

Phosphorus (P) availability and loss risk are linked to P species; however, their alternations in the soil amended with biochar-blended organic fertilizer is not well known, particularly under contrasting soil properties and land management. In this study, the variance of soil P species extracted by sequential chemical extraction (SCE) and 31P NMR techniques, as well as the degree of P saturation (DPS), were investigated throughout three paddy and three vegetable fields. These fields were amended with three different fertilizers at the same P application rate: chemical fertilizer (CF), organic fertilizer substitution (sheep manure/biogas slurry, SM/BS), and biochar-blended organic fertilizer substitution (BSM/BBS). Results showed that the BSM/BBS and SM increased the total P contents by 7.5% and 5.9% (TP) and available P contents by 30.1% and 19.2% (AP), but decreased the DPS values by 19.4% and 11.7%, compared to the CF treatment. Yet, the BS decreased the TP and AP contents but increased the DPS values across the experimental sites. In the BSM/BBS amended soils, high AP contents were due to the increased inorganic P (NaHCO3-Pi), while the increased organic P (monoester and DNA) induced low DPS values and reduced soil P loss risk. Our study highlights that biochar-blended organic fertilizer is an effective agronomic way for improving P availability and decreasing P loss risk via the alteration of soil P species.

A review of the physiological functions of blueberry anthocyanins and their applications in food

Anthocyanins are a class of water-soluble natural pigments, which are widely used in the food field because of their high nutritional value and various physiological functions. The extraction and purification technology of blueberry anthocyanins is one of the hot spots of research, and new techniques to improve the extraction rate and utilization have been emerging in recent years. This paper reviews the chemical structure, types, extraction and purification techniques, physiological functions and applications of blueberry anthocyanins in the food field, and gives an outlook on the application prospects, in order to provide scientific guidance and theoretical reference for the development and technical improvement of blueberry related products.

Sequential extraction and fractionation of four polysaccharides from cultivated brown algae Saccharina latissima and Alaria esculenta

Norway has a well-established seaweed industry based on extraction of alginates from wild harvested brown algae, Laminaria hyperborea (LH). However, further expansion of wild harvest is limited, and cultivated seaweed can contribute to meeting increasing demands for high value compounds in an environmentally sustainable manner. Herein, an integrated process for retrieving alginate, fucoidan, laminarin and cellulose was established for cultivated Saccharina latissima (SL) and Alaria esculenta (AE). Focus was to develop a process using mild chemical methods that do not compromise the molecular weights (MW) of the polysaccharides, particularly with respect to alginate. Response surface methodology (RSM) was applied to optimize the yield of fucoidan and laminarin and assess the effect of the applied extraction parameters: pH, temperature, and time, on the MW of subsequently extracted alginates. RSM confirmed that high yields of fucoidan and laminarin can be achieved while maintaining the alginate MW. Optimized conditions were applied in a pilot scale process, where all four polysaccharides were extracted. Purity (ranging from 40 up to 98 %) and composition of the components were evaluated combining several analytical techniques. Total yields of the polysaccharides were 23.4 % of the entering dry biomass from SL and 26.3 % from AE, representing around 55 % of the estimated maximal yield. However, all extractions were not optimized, and a mass balance revealed that <75 % more alginates could have been collected. The process can be adapted to simultaneously collect mannitol, which accounted for <15 % of the dry weight. The alginates were further examined by producing hydrogels, showing that the gel properties are comparable to alginates from LH fronds. The study demonstrated that mild chemical extraction techniques can be combined to extract all four polysaccharides from SL and AE, providing a foundation for a multicomponent biorefinery using cultivated brown algae.

Effect of Surface Modification of Himalayan Nettle Fiber and Characterization of the Morphology, Physical and Mechanical Properties

Abstract The process of retting bast fiber plants for the production of long fiber has presented major challenges. Water retting, dew retting, chemical extraction, and micro-organism (fungi, enzymes) techniques were applied to the extraction of natural fibers. The two nettle samples were extracted with water retting for 14 days and dew retting for 4 weeks. This research investigated the effects on the traditional retting process of nettle fiber by fungi and bacteria formation in lignocellulosic. The latter biological extraction methods successfully degraded the lignin and pectin materials of the fiber and increases the cellulose content. These extraction methods produced high quality fiber and tensile strength at a low cost. This study determined the chemical, physical, and mechanical characteristics such as fiber cellulose, non-cellulosic content, tensile strength, tenacity, and elongation break to see how treatments affected them. The treated fiber surface morphology was characterized using scanning electron microscopy. To evaluate functional group alterations, Fourier-transform infrared spectroscopy was used on the fiber specimen.

Novel extraction protocol for evaluating abundances and structural features of amorphous SiO2

Spectral data from satellite and rover missions on Mars identified significant abundances of amorphous phases in most samples analyzed, and SiO2 is the principal amorphous constituent in the Gale crater. Identifying and quantifying these short-range ordered, highly reactive phases is challenging but necessary to gain insight into the evolution of these materials. Terrestrial analogs are frequently employed to allow detailed analyses that cannot be performed on Martian samples. Historically, chemical extraction techniques have been extensively used to characterize amorphous materials in terrestrial soils, but most automated systems are complex, expensive, and limited to analyzing a single sample at one time. This study aims to develop a cost-effective apparatus that will allow latitude in choosing an extractant, process several samples simultaneously, enable rapid sampling over time without interruption and provide the resolution for quantitative differentiation of rapidly dissolving SiO2(a) phases in natural samples. Dissolution rates as a function of time were used as input for kinetic models to estimate the abundances of amorphous phases. When 2 M Na2CO3 is used as the extractant, dissolution rates differ significantly between secondary phases such as opal and primary glass phases. A stronger base, NaOH, is necessary for the complete dissolution of basaltic glass. Palagonitic tuffs from Iceland (proposed analogs of Martian soils) with >90% (w/w) amorphous composition were analyzed with 2 M Na2CO3 in the proposed apparatus, and both primary glass and secondary SiO2 appear to be present. Using the kinetic model of the dissolution, the palagonitic tuff has a composition of approximately 25% (w/w) of a rapidly reacting amorphous phase and 13% (w/w) of the slower reacting glass-like phase. The proposed high-efficiency analytical method can be applied to screen multiple terrestrial analogs and archive dissolution kinetics of many standard amorphous minerals. Although this paper focuses on extracting SiO2(a), the same setup can be applied to study time-based dissolution reactions using other extractants such as ammonium oxalate oxalic acid.

Advances in Chemical Composition, Extraction Techniques, Analytical Methods, and Biological Activity of Astragali Radix.

Astragali Radix (AR) is one of the well-known traditional Chinese medicines with a long history of medical use and a wide range of clinical applications. AR contains a variety of chemical constituents which can be classified into the following categories: polysaccharides, saponins, flavonoids, amino acids, and trace elements. There are several techniques to extract these constituents, of which microwave-assisted, enzymatic, aqueous, ultrasonic and reflux extraction are the most used. Several methods such as spectroscopy, capillary electrophoresis and various chromatographic methods have been developed to identify and analyze AR. Meanwhile, this paper also summarizes the biological activities of AR, such as anti-inflammatory, antioxidant, antitumor and antiviral activities. It is expected to provide theoretical support for the better development and utilization of AR.

The dynamic changes of phosphorus availability in straw/biochar-amended soils during the rice growth revealed by a combination of chemical extraction and DGT technique

The dynamic changes of phosphorus availability in straw/biochar-amended soils during the rice growth revealed by a combination of chemical extraction and DGT technique

Chemical Leaching of Sulfidic Mining Waste, Plombières Tailings Pond, Eastern Belgium: Insights from a Mineralogical Approach

Historic sulfidic mine waste material poses both an economic opportunity and an environmental threat (e.g., acid mine drainage). Due to low metal content in the mine waste and complex mineralogy, metal extraction of metal of interest is challenging. The Plombières tailings pond in eastern Belgium was selected as a case study to determine the potential for metal extraction of targeted metals from three different types of mine waste (metallurgical waste, brown, and yellow tailings). Material from this historic tailing originates from the exploitation and pyrometallurgical processing of the Mississippi Valley-type ores. The examined mine waste contains amounts of lead and zinc which can be potentially recovered by developing a hydrometallurgical method, which is selective for zinc and lead with respect to iron. From the three selected chemical extraction techniques, i.e., sulfuric acid, methanesulfonic acid, and sodium hydroxide solutions, the best results were given by sodium hydroxide solution leaching, due to negligible concentration of Fe in pregnant leaching solution, and leached metals were not precipitated into new mineral phases. Pb and Zn showed, however, a leaching efficiency of only 22% (0.0–63.6%) and 14% (0.0–29.1%) in average respectively. Furthermore, this study investigated how the mineralogy of mine waste material influences the leaching efficiency of the samples. Regardless of the lixiviant and the material, the highest leaching efficiency of Pb and Zn was achieved for samples where abundant Pb and Zn minerals were present. In samples where no Pb- or Zn-bearing minerals were detected, leaching efficiency was lower or negligible.