Pineapple fruit bromelain affinity to different protein substrates

Purification and characterization of a new trypsin-like protease from Crotalaria stipularia

Proteases are the main enzymes traded worldwide-comprising 60% of the total enzyme market-and are fundamental to the degradation and processing of proteins and peptides. Due to their high commercial demand and biological importance, there is a search for alternative sources of these enzymes. Crotalaria stipularia is highlighted for its agroecological applications, including organic fertilizers, nematode combat, and revegetation of areas contaminated with toxic substances. Considering the pronounced biotechnological functionality of the studied species and the necessity to discover alternative sources of proteases, we investigated the extraction, purification, and characterization of a protease from seeds of the C. stipularia plant. Protease isolation was achieved by three-phase partitioning and single-step molecular exclusion chromatography in Sephacryl S-100, with a final recovery of 47% of tryptic activity. The molecular mass of the isolated enzyme was 40 kDa, demonstrating optimal activities at pH 8.0 and 50 °C. Enzymatic characterization demonstrated that the protease can hydrolyze the specific trypsin substrate, BApNA. This trypsin-like protease had a Km, Vmax, Kcat, and catalytic efficiency constant of 0.01775 mg/mL, 0.1082 mM/min, 3.86 s-1, and 217.46, respectively.

Fatty acid modification of casein bioactive peptides nano-assemblies, synthesis, characterization and anticarcinogenic effect

In this study, the nano-assemblies of bovine casein hydrolyzed peptides (HP) modified by fatty acids with various alkyl chain lengths (C8, C10, C12 and C14) were synthesized. The physicochemical properties of HP-C8-HP-C14 nano-assemblies were characterized using spectra, laser particle size analyzer, contact angle meter, scanning electron microscope (SEM) and cryo-transmission electron microscope (Cryo-TEM). HP-C8 and HP-C10 self-assembled into a hollow cube cage with an average size of ~500 nm, and the assembly of HP-C12 showed a flower-shaped morphology with more dispersed behavior, and droplet size was observed as ~20 nm. The in vitro cytotoxicity against human breast cancer cells MCF-7 was tested using CCK-8 assay and flow cytometry analysis. HP-C12 showed the highest cytotoxicity for MCF-7 cells with an inhibition rate of 66.03 % ± 0.35 % with an IC50 value of 7.4 μM among HP-Cn. HP-C8, HP-C10 and HP-C12 significantly affected on the migration, invasion and apoptosis of MCF-7 cells. The apoptosis mechanism may depend on the upregulation of anti-apoptotic protein Bcl-2 as well as pro-apoptotic proteins Bax and caspase-8. The dead MCF-7 cells were analyzed with UHPLC-MS/MS using untargeted metabolomics, revealing key metabolic pathways.

Development of Biodegradable Thermosetting Plastic Using Dialdehyde Pineapple Stem Starch

Starch extracted from pineapple stem waste underwent an environmentally friendly modification process characterized by low-energy consumption. This process resulted in the creation of dialdehyde pineapple stem starch featuring varying aldehyde contents ranging from 10% to 90%. Leveraging these dialdehyde starches, thermosetting plastics were meticulously developed by incorporating glycerol as a plasticizer. Concurrently, unmodified pineapple stem starch was employed as a control to produce thermoplastic material under identical conditions. The objective of streamlining the processing steps was pursued by adopting a direct hot compression molding technique. This enabled the transformation of starch powders into plastic sheets without the need for water-based gelatinization. Consequently, the dialdehyde starch-based thermosetting plastics exhibited exceptional mechanical properties, boasting a modulus within the range of 1862 MPa to 2000 MPa and a strength of 15 MPa to 42 MPa. Notably, their stretchability remained relatively modest, spanning from 0.8% to 2.4%. Comparatively, these properties significantly outperformed the thermoplastic counterpart derived from unmodified starch. Tailoring the mechanical performance of the thermosetting plastics was achieved by manipulating the glycerol content, ranging from 30% to 50%. Phase morphologies of the thermoset starch unveiled a uniformly distributed microstructure without any observable starch particles. This stood in contrast to the heterogeneous structure exhibited by the thermoplastic derived from unmodified starch. X-ray diffraction patterns indicated the absence of a crystalline structure within the thermosets, likely attributed to the establishment of a crosslinked structure. The resultant network formation in the thermosets directly correlated with enhanced water resistance. Remarkably, the thermosetting starch originating from pineapple stem starch demonstrated continued biodegradability following a soil burial test, albeit at a notably slower rate when compared to its thermoplastic counterpart. These findings hold the potential to pave the way for the utilization of starch-based products, thereby replacing non-biodegradable petroleum-based materials and contributing to the creation of more enduring and sustainable commodities.

Growth Performance, Feed Utilisation, Endogenous Digestive Enzymes, Intestinal Morphology, and Antimicrobial Effect of Pacific White Shrimp (Litopenaeus vannamei) Fed with Feed Supplemented with Pineapple Waste Crude Extract as a Functional Feed Additive

This study used pineapple waste crude extract (PWCE) to increase the potential of Pacific white shrimp (Litopenaeus vannamei) production for food sustainability and stability. The objective was to investigate the appropriate technique to increase the yield production and quality of shrimp and decrease waste from shrimp culture. Pacific white shrimp (average body size: 0.51 g) were fed with commercial feed supplemented with PWCE at various concentrations of 0 (control), 90, 170, and 250 ppt. Shrimp were fed five times per day for 80 days. At the end of the trial, the results showed that shrimp fed with the PWCE 250 ppt supplementation provided the highest growth rate and the best feed utilisation and yield (P < 0.05). The protein content of whole shrimp in all shrimp fed with the PWCE supplementation diet was higher than that in the control group (P < 0.05). On the contrary, the variation of endogenous digestive enzymes, including protease, trypsin, and the T/C ratio, was significantly lower in shrimp fed a diet supplemented with PWCE 250 ppt (P < 0.05). While in this group, the number of microorganisms on thiosulfate-citrate-bile salt-sucrose (TCBS), blood agar, and trypticase soy agar (TSA) was lowest (P < 0.05). Furthermore, the dietary PWCE at 250 ppt increased the volume of microvilli in the hindgut of shrimp, but the supplementation at 170 ppt improved the number of F-cells in the epithelial cells of the hepatopancreas. Nevertheless, the supplementation of PWCE in the diet did not affect the water quality (P > 0.05). Therefore, pineapple waste crude extract supplementation improves both quantitative and qualitative yields and tends to reduce waste.

Application of Plant Proteases in Meat Tenderization: Recent Trends and Future Prospects

Papain, bromelain, and ficin are commonly used plant proteases used for meat tenderization. Other plant proteases explored for meat tenderization are actinidin, zingibain, and cucumin. The application of plant crude extracts or powders containing higher levels of compounds exerting tenderizing effects is also gaining popularity due to lower cost, improved sensory attributes of meat, and the presence of bioactive compounds exerting additional benefits in addition to tenderization, such as antioxidants and antimicrobial effects. The uncontrolled plant protease action could cause excessive tenderization (mushy texture) and poor quality due to an indiscriminate breakdown of proteins. The higher cost of separation and the purification of enzymes, unstable structure, and poor stability of these enzymes due to autolysis are some major challenges faced by the food industry. The meat industry is targeting the recycling of enzymes and improving their stability and shelf-life by immobilization, encapsulation, protein engineering, medium engineering, and stabilization during tenderization. The present review critically analyzed recent trends and the prospects of the application of plant proteases in meat tenderization.

Production and analysis of metabolites from Solid-State Fermentation of Chenopodium formosanum (Djulis) Sprouts in a Bioreactor

The study utilized fresh fourth-day Chenopodium formosanum sprouts as the substrate for Rhizopus oligosporus fermentation. The resultant products showed higher antioxidant capacity than those from C. formosanum grains. Compared to traditional plate fermentation (PF), fermentation in a bioreactor (BF) (35 °C, 0.4 vvm aeration at 5 rpm) led to higher free peptide content (99.56 ± 7.77 mg casein tryptone/g) and enzyme activity (amylase, glucosidase, and proteinase are 2.21 ± 0.01, 54.57 ± 10.88, and 40.81 ± 6.52 U/g, respectively) than traditional plate fermentation (PF). Using mass spectrometry analysis, two peptides TDEYGGSIENRFMN and DNSMLTFEGAPVQGAAAITEK were predicted to possess high bioactive properties as DPP IV and ACE inhibitors. Additionally, over twenty new metabolites (aromatics, amines, fatty acids, and carboxylic acids) were discovered in the BF system compared to its PF counterpart. Results suggest that using a BF system to ferment C. formosanum sprouts is an appropriate method to scale-up fermentation and enhance nutritional values as well as bioactivities.

Anticancer properties of bromelain: State-of-the-art and recent trends

Bromelain is a key enzyme found in pineapple (Ananas comosus (L.) Merr.); a proteolytic substance with multiple beneficial effects for human health such as anti-inflammatory, immunomodulatory, antioxidant and anticarcinogenic, traditionally used in many countries for its potential therapeutic value. The aim of this updated and comprehensive review focuses on the potential anticancer benefits of bromelain, analyzing the cytotoxic, apoptotic, necrotic, autophagic, immunomodulating, and anti-inflammatory effects in cancer cells and animal models. Detailed information about Bromelain and its anticancer effects at the cellular, molecular and signaling levels were collected from online databases such as PubMed/MedLine, TRIP database, GeenMedical, Scopus, Web of Science and Google Scholar. The results of the analyzed studies showed that Bromelain possesses corroborated pharmacological activities, such as anticancer, anti-edema, anti-inflammatory, anti-microbial, anti-coagulant, anti-osteoarthritis, anti-trauma pain, anti-diarrhea, wound repair. Nonetheless, bromelain clinical studies are scarce and still more research is needed to validate the scientific value of this enzyme in human cancer diseases.

Heterologous Expression and Catalytic Properties of Codon-Optimized Small-Sized Bromelain from MD2 Pineapple

Bromelain is a unique enzyme-based bioactive complex containing a mixture of cysteine proteases specifically found in the stems and fruits of pineapple (Ananas comosus) with a wide range of applications. MD2 pineapple harbors a gene encoding a small bromelain cysteine protease with the size of about 19 kDa, which might possess unique properties compared to the other cysteine protease bromelain. This study aims to determine the expressibility and catalytic properties of small-sized (19 kDa) bromelain from MD2 pineapple (MD2-SBro). Accordingly, the gene encoding MD2-SBro was firstly optimized in its codon profile, synthesized, and inserted into the pGS-21a vector. The insolubly expressed MD2-SBro was then resolubilized and refolded using urea treatment, followed by purification by glutathione S-transferase (GST) affinity chromatography, yielding 14 mg of pure MD2-SBro from 1 L of culture. The specific activity and catalytic efficiency (k_cat/K_m) of MD2-SBro were 3.56 ± 0.08 U mg⁻¹ and 4.75 ± 0.23 × 10⁻³ µM⁻¹ s⁻¹, respectively, where optimally active at 50 °C and pH 8.0, and modulated by divalent ions. The MD2-SBro also exhibited the ability to scavenge the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) with an IC₅₀ of 0.022 mg mL⁻¹. Altogether, this study provides the production feasibility of active and functional MD2-Bro as a bioactive compound.

Pineapple (Ananas comosus L.) By-Products Valorization: Novel Bio Ingredients for Functional Foods

Pineapple is consumed on a large scale around the world due to its appreciated sensorial characteristics. The industry of minimally processed pineapple produces enormous quantities of by-products (30–50%) which are generally undervalued. The end-of-life of pineapple by-products (PBP) can be replaced by reuse and renewal flows in an integrated process to promote economic growth by reducing consumption of natural resources and diminishing food waste. In our study, pineapple shell (PS) and pineapple core (PC), vacuum-packed separately, were subjected to moderate hydrostatic pressure (225 MPa, 8.5 min) (MHP) as abiotic stress to increase bromelain activity and antioxidant capacity. Pressurized and raw PBP were lyophilized to produce a stable powder. The dehydrated samples were characterized by the following methodologies: chemical and physical characterization, total phenolic compounds (TPC), antioxidant capacity, bromelain activity, microbiology, and mycotoxins. Results demonstrated that PBP are naturally rich in carbohydrates (66–88%), insoluble (16–28%) and soluble (2–4%) fiber, and minerals (4–5%). MHP was demonstrated to be beneficial in improving TPC (2–4%), antioxidant activity (2–6%), and bromelain activity (6–32%) without affecting the nutritional value. Furthermore, microbial and mycotoxical analysis demonstrated that powdered PC is a safe by-product. PS application is possible but requires previous decontamination to reduce the microbiological load.

Bromelain a Potential Bioactive Compound: A Comprehensive Overview from a Pharmacological Perspective

Bromelain is an effective chemoresponsive proteolytic enzyme derived from pineapple stems. It contains several thiol endopeptidases and is extracted and purified via several methods. It is most commonly used as an anti-inflammatory agent, though scientists have also discovered its potential as an anticancer and antimicrobial agent. It has been reported as having positive effects on the respiratory, digestive, and circulatory systems, and potentially on the immune system. It is a natural remedy for easing arthritis symptoms, including joint pain and stiffness. This review details bromelain's varied uses in healthcare, its low toxicity, and its relationship to nanoparticles. The door of infinite possibilities will be opened up if further extensive research is carried out on this pineapple-derived enzyme.

Identification and Comparison of Peptides from Chickpea Protein Hydrolysates Using Either Bromelain or Gastrointestinal Enzymes and Their Relationship with Markers of Type 2 Diabetes and Bitterness

The chickpea (Cicer arietinum L.) is one of the most important pulses worldwide. The objective was to identify, compare and evaluate peptides from chickpea hydrolysates produced by two enzymatic treatments. The antidiabetic potential and bitterness of the peptides and induction of bitter receptors were identified in silico. Proteins were isolated from the Kabuli variety. Peptides were produced from the proteins using a simulated digestive system (pepsin/pancreatin, 1:50 Enzyme/Protein, E/P), and these peptides were compared with those produced via bromelain hydrolysis (1:50 E/P). The protein profiles, sequences and characteristics of the peptides were evaluated. The biochemical inhibition and molecular docking of dipeptidyl peptidase-IV (DPP-IV), α-amylase and α-glucosidase were also studied. The molecular docking identified peptides from enzymatic hydrolysis as inhibitors of DPP-IV. The high hydrophobicity of the peptides indicated the potential for bitterness. There was no correlation between peptide length and DPP-IV binding. Peptides sequenced from the pepsin/pancreatin hydrolysates, PHPATSGGGL and YVDGSGTPLT, had greater affinity for the DPP-IV catalytic site than the peptides from the bromelain hydrolysates. These results are in agreement with their biochemical inhibition, when considering the inhibition of sitagliptin (54.3 µg/mL) as a standard. The bitter receptors hTAS2R38, hTAS2R5, hTAS2R7 and hTAS2R14 were stimulated by most sequences, which could be beneficial in the treatment of type 2 diabetes. Chickpea hydrolysates could be utilized as functional ingredients to be included in the diet for the prevention of diabetes.

Extraction and crosslinking of bromelain aggregates for improved stability and reusability from pineapple processing waste

The present study is first of its kind that focuses upon the extraction of bromelain from pineapple core waste and stabilising it as insoluble cross-linked aggregates. The influence of process variables such as the choice of precipitant, type of cross-linker, concentration of cross-linker and the reaction time for cross-linking step was investigated upon the activity recovery of bromelain cross-linked aggregates. The optimization of this biocatalyst preparation specifically recovered 87% of the enzymatic activity available in pineapple core waste by ammonium sulphate (60%, w/v) precipitation followed by cross-linking for 4 h with 80 mM glutaraldehyde. Cross-linked bromelain aggregates were thermally more stable and exhibited higher pH stability in comparison to free bromelain. The cross-linked bromelain aggregates exhibited higher operational stability in different organic solvents at 4 °C. The highest operational stability (% stability given in parenthesis) was observed in acetone (100%) followed by hexane (53.6%), ethyl acetate (39.6%), ethanol (32.5%) and chloroform (14.9%). The kinetic studies revealed higher Km value (5.45 mM) after the formation of cross-linked bromelain aggregates as compared to free bromelain (5.04 mM) with almost similar Vmax values. Cross-linked bromelain aggregates also showed significant reusability characteristics with an activity retention of >85% after 5-time cycles. Such recyclability of bromelain cross-linked aggregates could lead to potential industrial applications in both food and non-food sector. In addition, the present extraction method avoids costs related to purification and expensive immobilization carriers.

Enzyme activity and partial characterization of proteases obtained from Bromelia karatas fruit and compared with Bromelia pinguin proteases

The enzymatic activity and partial characterization of proteases from Bromelia karatas fruits were evaluated and compared with Bromelia pinguin proteases. The specific activity increased twofold after partial purification in both proteases. Partially purified proteases from Bromelia karatas showed good specific activity at pH 6.0-8.0 and residual activity of 70-100% for 60 min at 37-60 °C, similar to Bromelia pinguin proteases. The K m value of proteases from Bromelia karatas was higher (253.32 µM) than that of Bromelia pinguin proteases (234.94 µM). The use of specific protease inhibitors indicated the presence of cysteine and serine proteases. Proteases with molecular weight of 66.2-97 and 21-31 kDa were detected. Bromelia karatas proteases registered 73% hydrolysis using a soy protein concentrate, similar to the enzyme activity of Bromelia pinguin proteases and commercial bromelain. These results demonstrate that Bromelia karatas proteases could be a potential alternative protease in the food industry.

Antiacanthain A: New proteases isolated from Bromelia antiacantha Bertol. (Bromeliaceae)

Crude extract (CE) from pulp of Bromelia antiacantha Bertol. mature fruit, contains at least 3 cysteine proteases with proteolytic activity. By single step cation exchange chromatography (Hi-trap SP-HP) of partially purified CE, the protease with the lowest pI, Antiacanthain A (AntA), was isolated. It showed maximum activity at pH9, and 75% of remaining activity was maintained over a wide pH range (pH6-10). The AntA activity exhibits a constant increase up to 70°C. Maintains almost 100% of its activity at 45 at pH6 and 9. A 60% of AntA was active by titration with specific inhibitor, E64. Amidasic activity was studied with pyroglutamyl-phenyl-leucyl-paranitroaniline (PFLNA) substrate having higher AntA catalytic efficiency of (k_cat/K_m=470s^-1M^-1) relative to stem bromelain (k_cat/K_m=305s^-1M^-1). Esterase activity using p-nitrophenyl esters of N-α-CBZ-l-Lysine (z-L-LysONp) showed a 10-fold higher catalytic efficiency for AntA (k_cat/K_m=6376s^-1M^-1) relative to stem bromelain (k_cat/K_m=688s^-1M^-1). Incubation with 8M Urea did not affect AntA activity and remained unchanged for 18h, with 6M GndHCl resulted in a 41% decrease in activity after 30min incubation, maintained this activity 18h. AntA exhibits high sequence identity with proteases of the Bromeliaceae family.

Bromelain: from production to commercialisation

Bromelain is a mixture of proteolytic enzymes found in pineapple (Ananas comosus) plants. It can be found in several parts of the pineapple plant, including the stem, fruit, leaves and peel. High demand for bromelain has resulted in gradual increases in bromelain production. These increases have led to the need for a bromelain production strategy that yields more purified bromelain at a lower cost and with fewer production steps. Previously, bromelain was purified by conventional centrifugation, ultrafiltration and lyophilisation. Recently, the development of more modern purification techniques such as gel filtration, ion exchange chromatography, affinity chromatography, aqueous two-phase extraction and reverse micelle chromatography has resulted in increased industrial bromelain production worldwide. In addition, recombinant DNA technology has emerged as an alternative strategy for producing large amounts of ultrapure bromelain. An up-to-date compilation of data regarding the commercialisation of bromelain in the clinical, pharmaceutical and industrial fields is provided in this review. © 2016 Society of Chemical Industry.

The biochemical characterization, stabilization studies and the antiproliferative effect of bromelain against B16F10 murine melanoma cells

The current study aims to extract bromelain from different parts (stem, crown, peels, pulp and leaves) of Ananas comosus var. comosus AGB 772; to determine of optimum pH and temperature; to test bromelain stability in disodium EDTA and sodium benzoate, and to investigate its pharmacological activity on B16F10 murine melanoma cells in vitro. The highest enzymatic activity was found in bromelain extracted from the pulp and peel. The optimum bromelain pH among all studied pineapple parts was 6.0. The optimum temperature was above 50 °C in all bromelain extracts. The fluorescence analysis confirmed the stability of bromelain in the presence of EDTA and sodium benzoate. Bromelain was pharmacologically active against B16F10 melanoma cells and it was possible verifying approximately 100% inhibition of tumor cell proliferation in vitro. Since bromelain activity was found in different parts of pineapple plants, pineapple residues from the food industry may be used for bromelain extraction.

Enzymes in the dissolution testing of gelatin capsules

Gelatin capsules are a widely used dosage form both for pharmaceutical drug products as well as dietary supplements. Gelatin in the presence of certain compounds, mainly aldehydes, or in high humidity and high temperature conditions can cross-link. Cross-linking involves covalent bonding of the amine group of a lysine side chain of one gelatin molecule to a similar amine group on another molecule. The covalent bonding is, for practical purposes, irreversible. Cross-linking results in the formation of a pellicle on the internal or external surface of the gelatin capsule shell that prevents the capsule fill from being released. In vitro dissolution testing of cross-linked gelatin capsules can result in slower release of the drug or no release at all. The data obtained by the Gelatin Capsule Working Group, created in the early 90s to investigate noncompliance of gelatin capsules, was used to establish the type and amounts of enzymes that can be added to the dissolution medium in the case of test failure to the presence of cross-linking in the gelatin. The two-tier dissolution testing was included in the US Pharmacopeia and it recommends the addition of pepsin (pH below 6.8) or pancreatin (pH above 6.8) to the medium depending on its pH. Pepsin shows good protease activity up to pH 4 and pancreatin above pH 6 leaving a gap where neither one has good activity. Possible proteolytic enzymes that could be used for the pH range 4-6.8 could be papain or bromelain.

Functional properties of a cysteine proteinase from pineapple fruit with improved resistance to fungal pathogens in Arabidopsis thaliana

In plant cells, many cysteine proteinases (CPs) are synthesized as precursors in the endoplasmic reticulum, and then are subject to post-translational modifications to form the active mature proteinases. They participate in various cellular and physiological functions. Here, AcCP2, a CP from pineapple fruit (Ananas comosus L.) belonging to the C1A subfamily is analyzed based on the molecular modeling and homology alignment. Transcripts of AcCP2 can be detected in the different parts of fruits (particularly outer sarcocarps), and gradually increased during fruit development until maturity. To analyze the substrate specificity of AcCP2, the recombinant protein was overexpressed and purified from Pichia pastoris. The precursor of purified AcCP2 can be processed to a 25 kDa active form after acid treatment (pH 4.3). Its optimum proteolytic activity to Bz-Phe-Val-Arg-NH-Mec is at neutral pH. In addition, the overexpression of AcCP2 gene in Arabidopsis thaliana can improve the resistance to fungal pathogen of Botrytis cinerea. These data indicate that AcCP2 is a multifunctional proteinase, and its expression could cause fruit developmental characteristics of pineapple and resistance responses in transgenic Arabidopsis plants.