Freeze-dried Research Articles

Mechanism of the green coagulation processes on the construction of raw rubber network structure

AbstractAcid coagulation is the most traditional latex coagulation technology, but this coagulation process leads to delayed vulcanization, corrosiveness, and environmental pollution. Different coagulation processes significantly impact the raw rubber network structure, leading to differences in the properties of both raw rubber and rubber vulcanizates. Raw rubber was prepared by three acid‐free coagulation processes: freeze, microwave, and flash drying. The network density, molecular chain flexibility, molecular weight, processing fluidity, and plasticity retention of the raw rubber were characterized, and the vulcanization characteristics, viscoelasticity, mechanical properties, and dynamic mechanical properties of the cured rubber composites were investigated. Raw rubbers prepared by microwave drying and flash drying had higher crosslink density, more flexible molecular chains, larger molecular weight, and wider molecular weight distribution, thereby increasing the crosslink density of rubber vulcanizates. The crosslink density of the raw rubber prepared by microwave drying versus the acid coagulated raw rubber increased by 51% to 105.71 mol/m3, the tensile strength increased by 16% to reach 28.12 MPa, and the elastic modulus and rolling resistance under dynamic stress increased. This paper provides a new idea for analyzing the relationship between the raw rubber network structure and the properties of vulcanized rubber.Highlights Acid‐free raw rubbers are prepared by freeze, microwave, and flash drying. Coagulation processes significantly impact the raw rubber network structures. Effects of raw rubber network structures on properties are investigated. Crosslink density, plasticity retention, and tensile strength are improved.

Simple and scalable preparation of lignin based porous carbon coated nano-clay composites and their efficient removal for the diversified iodine

Here, lignin and nano-clay were used to prepare novel composite adsorbents by one-step carbonization without adding activators for radioactive iodine capture. Specially, 1D nano-clay such as halloysite (Hal), palygorskite (Pal) and sepiolite (Sep) were selected as skeleton components, respectively, enzymatic hydrolysis lignin (EHL) as carbon source, lignin based porous carbon/nano-clay composites (ELC-X) were prepared through ultrasonic impregnation, freeze drying, and carbonization. Characterization results indicated lignin based porous carbon (ELC) well coated on the surface of nano-clay, and made its surface areas increase to 252 m2/g. These composites appeared the micro-mesoporous hierarchical structure, considerable N doping and good chemical stability. Results of adsorption experiments showed that the introduction of ELC could well promote iodine vapor uptake of nano-clay, and up to 435.0 mg/g. Meanwhile, the synergistic effect between lignin based carbon and nano-clay was very significant for the adsorption of iodine/n-hexane and iodine ions, their capacity were far exceed those of a single material, respectively. The relevant adsorption kinetic and thermodynamics, and mechanism of ELC-X composites were clarified. This work provided a class of low-cost and environmentally friendly adsorbents for radioactive iodine capture, and opened up ideas for the comprehensive utilization of waste lignin and natural clay minerals.

Dry powder inhalation containing muco-inert ciprofloxacin and colistin co-loaded liposomes for pulmonary P. Aeruginosa biofilm eradication

Pseudomonas aeruginosa (PA), a predominant pathogen in lung infections, poses significant challenges due to its biofilm formation, which is the primary cause of chronic and recalcitrant pulmonary infections. Bacteria within these biofilms exhibit heightened resistance to antibiotics compared to their planktonic counterparts, and their secreted toxins exacerbate lung infections. Diverging from traditional antibacterial therapy for biofilm eradication, this study introduces a novel dry powder inhalation containing muco-inert ciprofloxacin and colistin co-encapsulated liposomes (Cipro-Col-Lips) prepared using ultrasonic spray freeze drying (USFD) technique. This USFD dry powder is designed to efficiently deliver muco-inert Cipro-Col-Lips to the lungs. Once deposited, the liposomes rapidly diffuse into the airway mucus, reaching the biofilm sites. The muco-inert Cipro-Col-Lips neutralize the biofilm-secreted toxins and simultaneously trigger the release of their therapeutic payload, exerting a synergistic antibiofilm effect. Our results demonstrated that the optimal USFD liposomal dry powder formulation exhibited satisfactory in vitro aerosol performance in terms of fine particle fraction (FPF) of 44.44 ± 0.78 %, mass median aerodynamic diameter (MMAD) of 4.27 ± 0.21 μm, and emitted dose (ED) of 99.31 ± 3.31 %. The muco-inert Cipro-Col-Lips effectively penetrate the airway mucus and accumulate at the biofilm site, neutralizing toxins and safeguarding lung cells. The triggered release of ciprofloxacin and colistin works synergistically to reduce the biofilm’s antibiotic resistance, impede the development of antibiotic resistance, and eliminate 99.99 % of biofilm-embedded bacteria, including persister bacteria. Using a PA-beads induced biofilm-associated lung infection mouse model, the in vivo efficacy of this liposomal dry powder aerosol was tested, and the results demonstrated that this liposomal dry powder aerosol achieved a 99.7 % reduction in bacterial colonization, and significantly mitigated inflammation and pulmonary fibrosis. The USFD dry powder inhalation containing muco-inert Cipro-Col-Lips emerges as a promising therapeutic strategy for treating PA biofilm-associated lung infections.

Encapsulation of felty germander (Teucrium polium L.) extract using the freeze-drying method.

Extracts with antimicrobial and antioxidant properties are limited in their application in food products due to their inability to withstand harsh environmental conditions, such as high temperatures and oxygen exposure. Therefore, the present study investigated the nanoencapsulation of Teucrium polium L. extract using the freeze-drying method to facilitate its application and protection against environmental factors. In this regard, an emulsion containing Teucrium polium L. extract at concentrations of 10%, 20%, and 30% and a mixture of maltodextrin/Persian gum in three ratios of 1:2, 1:1, and 2:1 as the coating wall were produced and then dried in a freeze dryer. In the following, the properties of emulsions and produced nanocapsules were studied. According to the results, emulsions with high amounts of Persian gum showed more stability, zeta potential, and viscosity. However, their particle size and polydisparity index were lower than those of other emulsions. As the extract concentration increased, there was a decrease in stability, zeta potential, and viscosity, accompanied by an increase in particle size and polydispersity index. Concurrently, elevated concentrations of maltodextrin, Persian gum, and extract resulted in higher humidity, density, encapsulation efficiency, and antioxidant activity of the capsules. The most optimal properties of emulsions and nanocapsules were achieved at the 10% concentration of Teucrium polium L. extract and the 1:1 ratio of maltodextrin/Persian gum mixture as the wall material. It is noteworthy that the release rate of phenolic compounds reached its maximum value (88%) after 60 days.

Comparative investigation on the phenolic compounds and antioxidant capacity of walnut kernel from different drying methods

Drying techniques are being used more and more to extend the shelf life of industrial products. Drying could influnce the content of phenolics in food and their antioxidant activity. This study estimated the effects of different drying methods (freeze drying (FD), gradient hot air drying (GHD), and constant hot air drying (CHD)) on phenolic profiles and antioxidant activities in walnut kernels. With a maximum content of 3.61 mg g−1, GHD was found to be the most effective in preserving total phenols, while CHD and FD had maximum contents of 2.66 mg g−1 and 1.96 mg g−1, respectively. The concentration of most monomeric phenols detected in the kernels increased with temperature, particularly in the free and bound forms. Gallic acid (free form) levels in GHD2 (194.54 µg g−1) were 55.77 and 60.08 times higher, respectively, than in FD and CHD. GHD dried walnuts had higher antioxidant activity than FD and CHD dried walnuts. Furthermore, bioinformatics analysis revealed three key metabolic pathways associated with the mechanisms underlying drying changes. The GHD technique, according to these findings, is a better choice for drying walnut in order to preserve its phenolics and antioxidant activity.Graphical

Simulation of the Effect of Air Humidity Ratio in the Drying Room on the Rate of Material Evaporation in Vacuum Freeze Drying

Simulation of the Effect of Air Humidity Ratio in the Drying Room on the Rate of Material Evaporation in Vacuum Freeze Drying

Microencapsulation of fish oil by spray drying, spray freeze-drying, freeze-drying, and microwave freeze-drying: Microcapsule characterization and storage stability.

The objective of this paper was to evaluate the effect of spray drying (SD), spray freeze-drying (SFD), freeze-drying (FD), and microwave freeze-drying (MFD) on the characteristics of fish oil (FO) microcapsules. The physicochemical properties, morphology, fatty acid composition, and stability of the microcapsules were analyzed. The encapsulation efficiencies of microcapsules dried by SD, SFD, FD, and MFD were 86.98%, 77.79%, 63.29%, and 57.89%, respectively. SD microcapsules exhibited superior properties in terms of effective loading capacity, color, and flowability. Conversely, SFD microcapsules demonstrated improved solubility. Microencapsulation positively affected the thermal stability of FO, but the content of unsaturated fatty acids decreased. The findings from the storage experiment indicated that the oxidative stability of SD fish oil microcapsules was marginally lower compared to microcapsules produced through three alternative drying techniques, all of which were based on the FD concept. The comparison of various drying methods and their effects on the quality of FO microcapsules offers valuable insights that can serve as a foundation for the industrial production of high-quality microcapsules.

The influence of drying and storage conditions on the volatilome and cannabinoid content of Cannabis sativa L. inflorescences

The increasing interest in hemp and cannabis poses new questions about the influence of drying and storage conditions on the overall aroma and cannabinoids profile of these products. Cannabis inflorescences are subjected to drying shortly after harvest and then to storage in different containers. These steps may cause a process of rapid deterioration with consequent changes in precious secondary metabolite content, negatively impacting on the product quality and potency. In this context, in this work, the investigation of the effects of freeze vs tray drying and three storage conditions on the preservation of cannabis compounds has been performed. A multi-trait approach, combining both solid-phase microextraction (SPME) two-dimensional gas chromatography coupled to mass spectrometry (SPME-GC × GC–MS) and high-performance liquid chromatography (HPLC), is presented for the first time. This approach has permitted to obtain the detailed characterisation of the whole cannabis matrix in terms of volatile compounds and cannabinoids. Moreover, multivariate statistical analyses were performed on the obtained data, helping to show that freeze drying conditions is useful to preserve cannabinoid content, preventing decarboxylation of acid cannabinoids, but leads to a loss of volatile compounds which are responsible for the cannabis aroma. Furthermore, among storage conditions, storage in glass bottle seems more beneficial for the retention of the initial VOC profile compared to open to air dry tray and closed high-density polyethylene box. However, the glass bottle storage condition causes formation of neutral cannabinoids at the expenses of the highly priced acid forms. This work will contribute to help define optimal storage conditions useful to produce highly valuable and high-quality products.Graphical

A comparative assessment of drying kinetics, energy consumption, mathematical modeling, and multivariate analysis of Indian borage (Plectranthus amboinicus) leaves

AbstractIn the current study, four drying methods, namely microwave (MD), vacuum (VD), hot air (HAD), and freeze drying (FD), were compared for drying of Indian borage (Plectranthus amboinicus) leaves for optimum energy consumption and bioactive compounds' retention. Effective moisture diffusivity for MD was about 100 times more than that of HAD and VD. MD at 600 W showed minimum specific energy consumption (4.04 kWh/kg), proving the most suitable drying condition. Moreover, it showed desirable energy values in terms of maximum specific moisture extraction rate (0.265 kg moisture/kWh) and maximum drying efficiency (15.85%). Bioactive compounds' retention in terms of phenols, antioxidants, and flavonoids was better in MD, followed by FD. Mathematical modeling of drying kinetics data revealed proper fitting of three drying models, namely, Aghbashlo, Modified Page‐II, and Page model, for explaining the drying behavior of Indian borage leaves. Multivariate characterization using principal component analysis revealed that FD and MD had a strong effect on bioactive compounds' retention, while VD and HAD showed least effect. Hence, based on optimum energy utilization and bioactive compounds' retention, MD at 600 W was selected for efficient drying of Indian borage leaves.Practical applicationsDrying of Indian borage leaves using microwave drying (MD) resulted in quicker drying with retention of bioactive compounds and color of dried leaves. The energy aspects were also favorable for industrial scale‐up. With due consideration to capacity enhancement in MD, it can prove to be a promising source of drying for culinary, medicinal, and aromatic plants.

Comparison of different drying technologies for coffee pulp tea: Changes in color, taste, bioactive and aroma components

Drying is a crucial process in the production of tea. The effects of sun drying (SD), hot air drying (HAD), microwave drying (MD), vacuum drying (VD) and freeze drying (FD) on the color, taste, bioactive, and aroma of coffee pulp tea (CPT) were evaluated systematically. The results showed that FD could better retain the original color, total phenolics (4.75 mg/mL), trigonelline (0.31 mg/mL), chlorogenic acid (0.067 mg/mL), protocatechuic acid (0.81 mg/mL), and total soluble sugars (24.33 mg/mL) of CPT, but its drying time was longer (32.56 h), and the taste and flavor were the worst. HAD and SD displayed the highest loss rates of most bioactive components, exceeding 40%. In contrast, MD can better improve the quality of CPT, giving it a better color, superior retention of bioactive components, and the most attractive taste and aroma, and decrease the drying time by 66.1% and 96.5%, respectively. Overall, MD is a promising production method for obtaining high-value-added CPT products.

Effect drying process of white turmeric herb (Curcuma mangga) on antioxidant activity

Curcuma mangga is one of the herbal rhizome plants. It has good benefits as Curcuma longa, and it has advantage of having aroma like a mango. This study aims to determine the effect of drying process of Curcuma mangga herb toward antioxidant activity. There are eight drying variations (oven drying at 50, 60, 70, 80 and 90°C, sun drying, room temperature, and freeze drying). Extraction of Curcuma mangga powder was carried out by maceration using aquadest, this study didn’t used organic solvents because the solvent for herbal drink is water (aquadest). Curcuma mangga extract was analysed for its stability in room temperature, FTIR analysis, and antioxidant activity analysis using 0.02% DPPH. The entire process in this research was replicated three times and average results were obtained. Based on the results, it can be seen that Curcuma mangga extracts are not stable at room temperature (maximum at 6 hours). Based on spectra FTIR results, Curcuma mangga extracts have polar functional group because the solvent used for extraction is aquadest which is polar solvent. The best antioxidant activity results (%AA) of Curcuma mangga is vacuum freeze drying process with an IC50 value 106.95 ppm, it was classified as a moderate antioxidant.

Effect of different drying methods on the structure and properties of porous starch

In order to investigate the effects of different drying methods on the properties of porous starch. The present study used four drying methods, namely hot air drying (HD), spray drying (SPD), vacuum freeze drying (FD) and supercritical carbon dioxide drying (SCD) to prepare maize and kudzu porous starch. Findings indicated that the physicochemical properties (e.g., morphology, crystallinity, enthalpy value, porosity, surface area and water absorption capacity as well as dye absorption capacity, particle size) of porous starch were significantly affected by the drying method. Compared with other samples, SCD-treated porous starch exhibited the highest surface areas of the starch (2.943 and 3.139 m2/g corresponding to kudzu and maize, respectively), amylose content (22.02 % and 16.85 % corresponding to kudzu and maize, respectively), MB and NR absorption capacity (90.63 %, 100.26 % and 90.63 %, 100.26 %, corresponding to kudzu ad maize, respectively), and thermal stability, whereas HD-treated porous starch showed the highest water-absorption capacity (123.8 % and 131.31 % corresponding to kudzu and maize, respectively). The dye absorption of the maize and kudzu porous starch was positively correlated with surface area, according to Pearson's correlation analysis. Therefore, in this study, our aim was to explore the effects of different drying methods on the Structure and properties of porous starch, and provide reference for selecting the best drying method for its application in different fields.

Fast dissolving tablet

Fast dissolving tablets have emerged as a popular dosage form, particularly beneficial for pediatric and geriatric patients facing challenges such as dysphagia or hand tremors. These tablets dissolve quickly in saliva without needing water, enhancing compliance and effectiveness of therapy. They offer advantages like easy portability, accurate dosing, and improved bioavailability. Various technologies, including spray drying and melt granulation, have been developed for their manufacturing. This review provides comprehensive information on fast dissolving tablets, covering their definition, advantages, limitations, challenges, and available formulations. The design of an oral drug delivery system prioritizes convenience in administration and improved patient compliance, making it the preferred route of drug delivery despite certain drawbacks. Over the last decade, there has been a growing demand for Fast Disintegrating Tablets (FDTS), turning this field into a rapidly expanding area within the pharmaceutical industry. The formulation’s popularity and effectiveness have led to the development of various FDT technologies. These technologies aim to achieve rapid tablet disintegration and mouth dissolution within five seconds, eliminating the need for chewing or water intake. This characteristic is particularly advantageous for populations such as pediatrics, geriatrics, and patients facing difficulties in swallowing conventional tablets and capsules. The formulation of an easily administrable dosage form, considering challenges like swallowing difficulties and low patient compliance, has driven the creation of orally disintegrating tablets. Traditional preparation methods include spray drying, freeze drying, direct compression, molding, and sublimation. In addition, new technologies have been devised to enhance the production of orodispersible tablets.

RESPONSE SURFACE METHODOLOGY FOR THE OPTIMIZATION OF SWEET POTATOES (Ipomoea batatas) DRYING PROCESS CONDITIONS

The aim was optimization of sweet potatoes (Ipomoea batatas) drying process conditions with RSM to obtain high quality product is very vital as improper drying conditions can affect the composition of the dried sweet potatoes and thereby increases the risk of running into deterioration of the nutrient contents of the product and loss. Matured sweet potatoes were processed by washing, peeling and cut into required size. Samples obtained were dried in triplicate using DHG-9101 laboratory drying oven at different temperatures of 60, 65, and 70◦C and time of 480, 540 and 600 minutes at thickness size of 4, 5 and 6 mm by employing Design of Experiment (DOE). Statistical analysis based on central composite design was carried out. The significant factors were identified. The optimum conditions obtained were at a temperature of 60◦C, time of 480 minutes and thickness of 4 mm which resulted in final moisture content of 13.96%. From these results obtained, the use of response surface methodology in drying operation for optimizing sweet potatoes could be used. For further research, higher temperatures at lower drying time could be implemented. Also, other drying methods such as freeze drying and osmotic drying can be explored

Encapsulation of probiotic Lacticaseibacillus casei with whey protein isolate/soybean hull polysaccharide enhances cell viability in harsh conditions

Whey protein isolate (WPI)-soybean hull polysaccharide (SHP) Maillard reaction conjugates were used to encapsulate Lacticaseibacillus casei and determine the effect of encapsulation on bacterial viability during freeze drying, simulated pasteurization simulated gastrointestinal digestion and storage. The WPI-SHP conjugates were characterized by degree of conjugation, size-exclusion chromatography, infrared and fluorescence spectroscopy and other analyses. The degree of conjugation, the formation of Maillard reaction products and the content of high molecular weight conjugates increased with reaction time. The emulsification capacity and glass transition temperature (Tg) of the WPI-SHP conjugates peaked after 4 days of reaction, at a Tg of 140.51 ± 2.76 °C, an emulsification activity index of 9.12 m2/g and emulsion stability index of 87.01%. WPI-SHP4d had the best protection effect of probiotics under freeze drying, simulated pasteurization and gastrointestinal digestion. These findings provide valuable insights into the selection of encapsulating agents to improve probiotic viability in functional foods.

Impact of Drying Method and Solvent Extraction on Ethiopian Verbascum sinaiticum (Qetetina) Leaves: Metabolite Profiling and Evaluation of Antioxidant Capacity

The aim of this study was to evaluate the effects of different drying methods on bioactive compounds and to analyze their composition in Verbascum sinaiticum (V. sinaiticum) leaf extracts using UHPLC-ESI-QTOF-MS/MS. V. sinaiticum is traditionally used as an herbal medicine, yet it has undergone limited scientific investigations regarding its secondary metabolites. V. sinaiticum leaves were dried using oven dryers at 50 °C, 60 °C, and 70 °C, as well as a freeze dryer. The leaves were then extracted using 50% and 70% aqueous ethanol and 100% aqueous solutions. The results showed that the highest contents of TPC and TFC were observed when 70% aqueous ethanol was used during freeze drying, reaching 181.73 mg GAE/g dw and 78.57 mg CE/g dw, respectively. The strongest correlations were observed between the TFC and DPPH radical scavenging activity (0.9082), followed by TPC and ABTS assays (0.8933) and TPC and DPPH (0.8272). In the FTIR analysis, freeze drying exhibited a lower intensity of the phenolic -OH functional groups, contrasting with significant denaturation observed during oven drying at 70 °C. Metabolite analysis identified 29 compounds in V. sinaiticum leaves, further confirming the presence of 14 phenolic and flavonoid compounds, including kaempferol, catechin, gallic acid, and myricetin derivatives, consistent with the experimentally observed antioxidant capacity. This study highlights the impact of drying methods on the bioactive composition of V. sinaiticum and underscores its potential as a source of antioxidants for food, nutraceutical, and pharmaceutical applications.

Chemometric analysis illuminates the relationship among browning, polyphenol degradation, Maillard reaction and flavor variation of 5 jujube fruits during air-impingement jet drying

This study was designed to reveal the relationship among browning, polyphenol degradation, Maillard reaction (MR) and flavor variation in jujube fruit (JF) during air-impingement jet drying (AIJD). Five kinds of JFs were dried by AIJD at 60 °C and vacuum freeze drying. Colorimeter and chemometric analysis found that AIJD induced color changes of JF pulp and peel. AIJD also reduced the total polyphenols content and total flavonoids levels in JF. The Fe3+ reducing capacity and 2,2′-Azinobis-(3-ethylbenzothiazoline-6-sulphonate) cationic radical scavenging capacity of JF were reduced by 31.6% and 8.2%, respectively. Seven polyphenols were identified in JF, and epicatechin was found related to change of JF pulp color by sparse partial least square (sPLS). sPLS revealed that 3-deoxy glucosone, N-ε-carboxymethyl-l-lysine and 5-hydroxymethylfurfural associated with JF color. sPLS found that MR generated 3-methyl-butanoic acid and cyclobutanone during AIJD of JF. Chemometrics is an effective tool to disclose mechanism of color changes in food.

Optimization of ultrasound pre-treatment and the effect of different drying techniques on antioxidant capacity, bioaccessibility, structural and thermal properties of purple cabbage

Some of the challenges of purple cabbage post-harvest processing and shelf-life is the preservation of its bioactive compounds, especially anthocyanins– a water-soluble pigment of interest due to their health-promoting benefits. The current study proposes the application of ultrasound (US) as a pretreatment prior to convective drying (CD), freeze-drying (FD), spray drying (SD), or spouted bed drying (SB). For this, a Box-Behnken Design (BBD) evaluated the effect of the different drying techniques and selected US amplitudes (20–70 %) and times (4–12 min) on the antioxidant capacity, bioaccessibility, and structural and thermal properties of purple cabbage. The results demonstrated that the amplitude of 80.35 % and 8 min of US, yielded the highest total phenolic compounds (TPC) (80.46 mg GAE/100 g), total anthocyanins (TA) (9.85 mg/100 g), and antioxidant activity (29.74 µM Fe2SO4/g) levels. SD and SB stood out for preserving bioactive compounds, increasing solubility, and reducing powder hygroscopicity. In the Scanning Electron Microscopy (SEM) analysis, CD, FD, and SB exhibited irregular and rough surfaces, while SD displayed spherical particles. Changes in the intensities of Fourier-Transform Infrared Spectroscopy (FT-IR) spectra, especially in the bonds (C = C, 1020 cm−1) in SD and SB, suggest alterations in molecular interactions due to processing and the adjuvant. Differential scanning calorimetry (DSC) indicated that SD displayed greater thermal stability. In conclusion, US pre-treatment and appropriate selection of drying techniques significantly influenced the properties of purple cabbage powder, bringing insights for the food industry regarding the use of drying as a post-harvested treatment of purple cabbage.

Comparison of different drying technologies for kiwifruit pomace: Changes in physical characteristics, nutritional properties and antioxidant capacities

The objective of this study was to evaluate the impacts of different drying technologies including microwave drying (MD), vacuum microwave drying (VMD), sun drying (SD), vacuum drying (VD), hot air drying (HAD), and vacuum freeze drying (VFD) on the physical characteristics, nutritional properties and antioxidant capacities of kiwifruit pomace in order to realize by-product utilization and improve energy efficiency. Results showed that both MD and VMD significantly reduced drying time by >94.6%, compared to traditional thermal drying which took 14–48 h. MD exhibited the highest content of soluble dietary fiber (9.5%) and the lowest energy consumption. Furthermore, VMD resulted in the highest content of vitamin C (198.78 mg/100 g) and reducing sugar (73.78%), and the antioxidant capacities ranked only second to VFD. Given the financial advantages and product quality, VMD was suggested to be advantageous technology in actual industrial production.

Protein identification and potential bioactive peptides from pumpkin (Cucurbita maxima) seeds.

Pumpkin is an economically important crop all over the world. Approximately, 18%-21% of pumpkins, consisting of peels and seeds by-products, are wasted during processing. In addition, the seeds are rich in protein and have the potency of bioactive peptide production. This study aims to recognize the proteins and investigate the potential bioactive peptides from pumpkin (Cucurbita maxima) seeds. Pumpkin seeds were subjected to hot air drying (HAD) at 55°C for 12 h and freeze-drying (FD) at -80°C for 54 h before they were powdered, analyzed, and precipitated by isoelectric point to obtain pumpkin seed protein isolates (PSPI). PSPI comprised 11S globulin subunit beta, 2S seed storage albumin, and chaperonin CPN60-1. To generate hydrolysate peptides, PSPI was hydrolyzed using papain, pepsin, and bromelain. FD group pepsin hydrolysates had the highest peptide content of 420.83 mg/g. ACE inhibition and DPP-IV inhibition activity were analyzed for each enzymatic hydrolysate. The pepsin hydrolyzed sample exhibited the highest ACE inhibition of 70.26%, and the papain hydrolyzed sample exhibited the highest DPP-IV inhibition of 30.51%. The simulated gastrointestinal digestion (SGID) conducted by pepsin and pancreatin increased ACE inhibitory activity from 76.93% to 78.34%, and DPP-IV inhibited activity increased from 58.62% to 77.13%. Pepsin and papain hydrolysates were fractionated using ultrafiltration to measure ACE and DPP-IV inhibition activity. The highest free radical scavenging abilities were exhibited by the <1 kDa hydrolysate fractions with 78.34% ACE inhibitory activities and 79.55% DPP-IV inhibitory activities. This research revealed that pumpkin seeds had the potency to produce bioactive peptides.