Food Preservative Properties Research Articles

Unveiling plants with food preservative properties

Unveiling plants with food preservative properties

Effect of Layered Double Hydroxide and Its Localization on the Structure and Properties of PBAT/PPC Composites

AbstractThe blends of poly(butylene adipate‐co‐terephthalate) (PBAT), poly(propylene carbonate) (PPC), chain extender (ADR) and layered double hydroxides (LDH) are prepared by different extrusion methods. Effects of LDH and its distribution on rheology, phase morphology, mechanical properties, water vapor barrier properties and food preservation properties are investigated. Results show that when PBAT, PPC, and LDH are mixed directly, LDH is preferentially distributed in the PBAT phase. When LDH are mixed with PPC firstly and then further with PBAT, LDH mostly migrates to the interface of PBAT and PPC. The epoxy groups of ADR react with the terminal groups of the polymers to improve the interfacial compatibility. Adding LDH, the mechanical properties and barrier properties of the materials are improved and by premixing of PPC and LDH, properties of composites are further improved. Compared with PBAT/PPC blends, the tensile strength and elongation at break of PBAT/PPC(LDH‐0.5)/ADR increased by 25.2% and 15.3%, respectively. The banana packaged in PBAT/PPC/LDH films maintains good freshness. It illustrates that PBAT/PPC(LDH)/ADR composites have a good application prospect in the field of barrier and food packaging based on their excellent mechanical, barrier, and preservation properties.

Characterization of Moringa oleifera Seed Oil for the Development of a Biopackage Applied to Maintain the Quality of Turkey Ham.

Moringa oleifera has a high level of active chemicals that are useful in the food industry, and they have antibacterial and food preservation properties. The characterization of M. oleifera seed oil (MOS) may vary due to agronomic and environmental factors. Therefore, it was necessary to know the composition of lipids present in our oil extracted under pressing at 180 °C and thus determine if it is suitable to produce a biopackaging. Within the characterization of the oil, it was obtained that MOS presented high-quality fatty acids (71% oleic acid) with low values of acidity (0.71 mg KOH/g) and peroxide (1.74 meq O2/kg). Furthermore, MOS was not very sensitive to lipoperoxidation by tert-butyl hydroperoxide (tBuOOH) and its phenolic components, oleic acid and tocopherols, allowed MOS to present a recovery of 70% after 30 min of treatment. Subsequently, a biopackaging was developed using a multiple emulsion containing corn starch/carboxymethylcellulose/glycerol/MOS, which presented good mechanical properties (strength and flexibility), transparency, and a barrier that prevents the transfer of UV light by 30% and UV-C by 98%, as well as a flux with the atmosphere of 5.12 × 10-8 g/ m.s. Pa that prevents moisture loss and protects the turkey ham from O2. Hence, the turkey ham suffered less weight loss and less hardness due to its preservation in the biopackaging.

Physicochemical, antibacterial and food preservation properties of active packaging films based on chitosan/ε-polylysine-grafted bacterial cellulose

To address the environmental and food contamination issues caused by plastics and microorganisms, antimicrobial films using natural polymers has attracted enormous attention. In this work, we proposed a green, convenient and fast approach to prepare antimicrobial films from chitosan (CS), bacterial cellulose (BC) and ε-polylysine (ε-PL). The effects of different concentrations of ε-PL (0 %, 0.25 %, 0.5 %, 0.75 %, 1 %, w/v) on the physicochemical properties and antibacterial activity of composite films (CS-DABC-x%PL) were systematically investigated. Furthermore, a comprehensive comparison with purely physically mixed CS-BC-x%PL films provides a deeper understanding of the subject matter. Characterization tests of the films were conducted using scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results suggested that the incorporation of 0.5 % ε-PL reduced the water solubility of the composite film by 19.82 %, along with improved the tensile strength and thermal stability by 37.31 % and 28.54 %. As ε-PL concentration increased to 1 %, the antibacterial performance of the films gradually enhanced. Additionally, the CS-DABC-0.5%PL film demonstrated effectiveness in delaying the deterioration of tilapia. These findings imply that this novel green packaging material holds significant potential in food preservation due to its promising antibacterial properties.

Modified magnesium oxide/silver nanoparticles reinforced poly (butylene succinate-co-terephthalate) composite biofilms for food packaging application

MgO/Ag nanoparticles (NPs) were surface-modified with titanate coupling agent titaniumtriisostearoylisopropoxide (NDZ-130). A new antibacterial biofilm for food packaging was synthesized by combining the modified MgO/Ag NPs with poly (butylene succinate-co-terephthalate) (PBST). The modification improved the compatibility between the MgO/Ag NPs and the PBST matrix. The effects of the modified MgO/Ag NPs on biofilm mechanical, barrier, thermal, antibacterial and food preservation properties were evaluated. Compared with the PBST/MgO/Ag composite film, the modified PBST/MgO/Ag composite film showed an increase in tensile strength (TS) of 8.71% and elongation at break (EB) of 16.66%, additionally decreasing water vapor permeability (WVP) by 42.86%. The composite film also exhibited over 95% inhibition of Staphylococcus aureus and Escherichia coli. The modified PBST/MgO/Ag composite film avoided microbial contamination and preserved cherry tomatoes while maintaining moisture and firmness for six days. All results indicated that the prepared biofilms have a high potential for use as food packaging films.

Enhancing food preservation with postbiotic metabolites γ-aminobutyric acid (GABA) and bacteriocin-like inhibitory substances (BLIS) produced by Lactobacillus brevis C23 co-cultures in plant-based medium

Lactic acid bacteria (LAB) can produce γ-aminobutyric acid (GABA) with antioxidant properties and sedative effects when it binds to the GABA receptor in the human brain. LAB can also produce bacteriocin-like inhibitory substances (BLIS) with antimicrobial capabilities during carbohydrate fermentation. GABA and BLIS are natural compounds with potential health benefits and food preservation properties. Lactobacillus brevis C23 was co-cultured with three different LABs as inducers, which produced the highest GABA content and BLIS activity. They were cultured in various plant-based media to obtain an edible and better-tasting final product over commercially available media like MRS broth. A coconut-based medium with additives was optimized using response surface methodology (RSM) to increase GABA and BLIS production. The optimized medium for maximum GABA production (3.22 ± 0.01 mg/mL) and BLIS activity (84.40 ± 0.44%) was a 5.5% coconut medium containing 0.23% glucose, 1.44% Tween 20, 0.48% L-glutamic acid, and 0.02% pyridoxine. Due to the presence of GABA, the cell-free supernatant (CFS) as a postbiotic showed higher antioxidant activity than other food preservatives like nisin and potassium sorbate. Finally, microbiological tests on food samples showed that the postbiotic was more effective than other preservatives at combating the growth of LAB, molds and coliform bacteria, making it a possible food preservative.

Anthocyanins as Natural Plant-derived Antifungal Agents

Anthocyanins are polyphenolic compounds found as natural pigments in various parts of plants that share the same diphenyl propane skeleton (C6C3C6) and are collectively known as flavonoids. They are water-soluble pigments responsible for the blue, purple, and red color of various plant parts and are particularly abundant in fruits, flowers, and vegetables. These pigments are natural colorants that are low to non-toxic. They also show antifungal, antibacterial, antioxidant, and food preservative properties. This study aims to perform in vitro analysis of the antifungal activity of anthocyanins extracted from different plant materials. Anthocyanins were extracted in acetone and acidified methanol. For qualitative determination of anthocyanins, thin layer chromatography was used whereas for quantitative determination pH differential method was used. The antifungal potential of anthocyanins was determined using the MIC and agar well diffusion methods against Penicillium sp. and Aspergillus sp. Acetone extract exhibited higher antifungal potential compared to acidified methanol extract against both fungal strains. It is suggested that anthocyanins, being strong antifungal agents, can be used to prevent fungal spoilage and deterioration of processed foods.

PHOTOSYNTHETIC MICROORGANISMS AS SOURCE OF ANTIOXIDANT AND ANTIBACTERIAL BIOACTIVE COMPOUNDS OF INTEREST IN THE FOOD INDUSTRY

Bioactive compounds from microalgae and cyanobacteria have been frequently investigated as food preservatives due to their various biotechnological activities. Therefore, this study aimed to evaluate the antimicrobial and antioxidant activities of the aqueous and ethanolic extracts from Dunaliella tertiolecta, Tetradesmus obliquus, and Chlorella vulgaris microalgae and Arthrospira platensis cyanobacteria. The extracts were obtained through the sonication method and the antioxidant activity was determined by ABTS and DPPH methods, whereas antimicrobial activity was evaluated by microdilution assay. In general, ethanolic extracts of all microalgae showed higher antioxidant activity compared to aqueous extracts, especially using ABTS method. All bacteria exhibited higher resistance using the aqueous extracts. Specifically, the gram-negative Pseudomonas aeruginosa was the most susceptible pathogen and was inhibited by all microalgae. The highest antioxidant and antimicrobial activities were obtained by the ethanolic extract from Arthrospira platensis. These data show that ethanolic extract from Arthrospira platensis may be a potential source of antioxidant and antimicrobial compounds with food preservative properties.

Synergistic Antibacterial Screening of Cymbopogon citratus and Azadirachta indica: Phytochemical Profiling and Antioxidant and Hemolytic Activities.

Current studies were performed to investigate the phytochemistry, synergistic antibacterial, antioxidant, and hemolytic activities of ethanolic and aqueous extracts of Azadirachta indica (EA and WA) and Cymbopogon citratus (EC and WC) leaves. Fourier transform infrared data verified the existence of alcoholic, carboxylic, aldehydic, phenyl, and bromo moieties in plant leaves. The ethanolic extracts (EA and EC) were significantly richer in phenolics and flavonoids as compared to the aqueous extracts (WA and WC). The ethanolic extract of C. citratus (EC) contained higher concentrations of caffeic acid (1.432 mg/g), synapic acid (6.743 mg/g), and benzoic acid (7.431 mg/g) as compared to all other extracts, whereas chlorogenic acid (0.311 mg/g) was present only in the aqueous extract of A. indica (WA). Food preservative properties of C. citratus can be due to the presence of benzoic acid (7.431 mg/g). -Gas chromatography-mass spectrometry analysis demonstrated the presence of 36 and 23 compounds in A. indica and C. citratus leaves, respectively. Inductively coupled plasma analysis was used to determine the concentration of 26 metals (Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Si, Sn, Sr, V, Zn, Zr, Ti); the metal concentrations were higher in aqueous extracts as compared to the ethanolic extracts. The extracts were generally richer in calcium (3000-7858 ppm), potassium (13662-53,750 ppm), and sodium (3181-8445 ppm) and hence can be used in food supplements as a source of these metals. Antioxidant potential (DDPH method) of C. citratus ethanolic extract was the highest (74.50 ± 0.66%), whereas it was the lowest (32.22 ± 0.28%) for the aqueous extract of A. indica. Synergistic inhibition of bacteria (Staphylococcus aureus and Escherichia coli) was observed when the aqueous extracts of both the plants were mixed together in certain ratios (v/v). The highest antibacterial potential was exhibited by the pure extract of C. citratus, which was even higher than that of the standard drug (ciprofloxacin). The plant extracts and their mixtures were more active against S. aureus as compared to E. coli. No toxic hemolytic effects were observed for the investigated extracts indicating their safe medicinal uses for human beings.

Enhancing the applicability of gelatin-carboxymethyl cellulose films by cold plasma modification for the preservation of fruits

Cold plasma has been induced in polymer modification, but its influence on the properties of edible coatings in fruit preservation is unclear. In the present study, cold plasma was used to improve the practicability of Gelatin-carboxymethyl cellulose (GCMC). Cold plasma modification decreased the viscosity, cohesiveness, hardness, springiness and surface microroughness of GCMC to make it easy to implement during coating. The FTIR spectrum of cold-plasma-modified GCMC (CP-GCMC) film was like GCMC film with a shift towards lower wave numbers. However, CP-GCMC film exhibited higher water vapor permeability, but lower light transmittance and water solubility than GCMC film. Moreover, CP-GCMC film-coating showed good inhibition efficiency in decay rate, weight loss, respiration rate, fruit browning, and extended shelf lives of blueberry, apple and green walnut. These results indicated that cold plasma modification did not changed chemical structure, but improved the physical, microstructural and food preservation properties of GCMC films. Hence, cold plasma modification can be used as an effective technique to enhance the application and preservation potential of edible coatings.

Antioxidant Effect of Ocimum basilicum Essential Oil and Its Effect on Cooking Qualities of Supplemented Chicken Nuggets.

A commonly observed chicken meat issue is its lipid oxidation that leads to deterioration of its organoleptic and nutritional properties and its further-processed products. Basil (Ocimum basilicum L.) is one of the traditional culinary herbs exhibiting food preservation properties. The current study investigated the essential oil composition, antioxidant activity and in vitro cytotoxic capacity of the essential oil of basil indigenous to Pakistan. GC–MS analysis of the essential oil revealed the presence of 59 compounds that constituted 98.6% of the essential oil. O. basilicum essential oil (OB-EO) exhibited excellent antioxidant activity, i.e., IC50 5.92 ± 0.15 µg/mL as assayed by the DPPH assay, 23.4 ± 0.02 µmoL Fe/g by FRAP, and 14.6 ± 0.59% inhibition by H2O2. The brine shrimp lethality assay identified an average mortality of ~18% with OB-EO at 10–1000 µg/mL, while that of the same concentration range of the standard drug (etoposide) was 72%. OB-EO was found to be non-toxic to HeLa and PC-3 cell lines. TBARS contents were significantly decreased with increase of OB-EO in chicken nuggets. The lowest TBARS contents were recorded in nuggets supplemented with 0.3% OB-EO, whereas the highest overall acceptability score was marked to the treatments carrying 0.2% OB-EO. The results suggest OB-EO as a promising carrier of bioactive compounds with a broad range of food preservation properties, and which has a sensory acceptability threshold level for chicken nuggets falling between 0.2-0.3% supplementation. Future research must investigate the antibacterial impact of OB-EO on meat products preserved with natural rather than synthetic preservatives.

Choline oleate based micellar system as a new approach for Luteolin formulation: Antioxidant, antimicrobial, and food preservation properties evaluation

Luteolin (LUT), an important flavonoid, shows excellent antioxidant and antimicrobial properties. However, its low solubility and stability in water, as well as challenges related to its formulation, have limited its use in food preservation. Here, we develop a highly water-soluble LUT-loaded micellar formulation (LUT-MF) using a solid-in-water nanodispersion technique involving emulsification and lyophilization processes. LUT solubilized in an organic phase comprising acetone, methanol, and cyclohexane (5:10:85 v/v) was emulsified with an aqueous solution of a surface-active ionic liquid, choline oleate ([Cho][Ole]), and the oil in water emulsion was lyophilized to remove the organic phase and water and obtain a solid LUT-[Cho][Ole] complex. LUT-[Cho][Ole] complex was dispersed again in water to prepare the LUT-MF formulation with good stability. Dynamic light scattering and transmission electron microscopy confirmed that the LUT-MF formed spherical micelles with a mean particle size of approximately 73 nm. LUT-MF showed excellent encapsulation efficiency (94.3%) and enhanced aqueous solubility. An in vitro release study in PBS containing 30% ethanol demonstrated 3.94 times higher release of LUT from LUT-MF than from LUT suspension after 24 h. The developed formulation showed better antioxidant activity than both free LUT and ascorbic acid. LUT-MF demonstrated higher antibacterial activity than sodium benzoate. Food preservation studies revealed that treating strawberries with LUT-MF effectively preserved color and prevented shriveling and decay over 8 days storage at 10 °C, compared with sodium benzoate treatment. The results suggest that LUT-MF is a potential natural preservative alternative to conventional toxic chemical preservatives used in the food industry.

Terpenes and terpenoids as main bioactive compounds of essential oils, their roles in human health and potential application as natural food preservatives

Essential oils (EOs) are volatile and concentrated liquids extracted from different parts of plants. Bioactive compounds found in EOs, especially terpenes and terpenoids possess a wide range of biological activities including anticancer, antimicrobial, anti-inflammatory, antioxidant, and antiallergic. Available literature confirms that EOs exhibit antimicrobial and food preservative properties that are considered as a real potential application in food industry. Hence, the purpose of this review is to present an overview of current knowledge of EOs for application in pharmaceutical and medical industries as well as their potential as food preservatives in food industry.

Beyond Archaea: The Table Salt Bacteriome.

Commercial table salt is a condiment with food preservative properties by decreasing water activity and increasing osmotic pressure. Salt is also a source of halophilic bacteria and archaea. In the present research, the diversity of halotolerant and halophilic microorganisms was studied in six commercial table salts by culture-dependent and culture-independent techniques. Three table salts were obtained from marine origins: Atlantic Ocean, Mediterranean (Ibiza Island), and Odiel marshes (supermarket marine salt). Other salts supplemented with mineral and nutritional ingredients were also used: Himalayan pink, Hawaiian black, and one with dried vegetables known as Viking salt. The results of 16S rRNA gene sequencing reveal that the salts from marine origins display a similar archaeal taxonomy, but with significant variations among genera. Archaeal taxa Halorubrum, Halobacterium, Hallobellus, Natronomonas, Haloplanus, Halonotius, Halomarina, and Haloarcula were prevalent in those three marine salts. Furthermore, the most abundant archaeal genera present in all salts were Natronomonas, Halolamina, Halonotius, Halapricum, Halobacterium, Haloarcula, and uncultured Halobacterales. Sulfitobacter sp. was the most frequent bacteria, represented almost in all salts. Other genera such as Bacillus, Enterococcus, and Flavobacterium were the most frequent taxa in the Viking, Himalayan pink, and black salts, respectively. Interestingly, the genus Salinibacter was detected only in marine-originated salts. A collection of 76 halotolerant and halophilic bacterial and haloarchaeal species was set by culturing on different media with a broad range of salinity and nutrient composition. Comparing the results of 16S rRNA gene metataxonomic and culturomics revealed that culturable bacteria Acinetobacter, Aquibacillus, Bacillus, Brevundimonas, Fictibacillus, Gracilibacillus, Halobacillus, Micrococcus, Oceanobacillus, Salibacterium, Salinibacter, Terribacillus, Thalassobacillus, and also Archaea Haloarcula, Halobacterium, and Halorubrum were identified at least in one sample by both methods. Our results show that salts from marine origins are dominated by Archaea, whereas salts from other sources or salt supplemented with ingredients are dominated by bacteria.

Rosemary (Salvia rosmarinus): Health-Promoting Benefits and Food Preservative Properties

Natural food preservatives in the form of herb extracts and spices are increasing in popularity due to their potential to replace synthetic compounds traditionally used as food preservatives. Rosemary (Salvia rosmarinus) is an herb that has been traditionally used as an anti-inflammatory and analgesic agent, and currently is being studied for anti-cancer and hepatoprotective properties. Rosemary also has been reported to be an effective food preservative due to its high anti-oxidant and anti-microbial activities. These properties allow rosemary prevent microbial growth while decreasing food spoilage through oxidation. Rosemary contains several classes of compounds, including diterpenes, polyphenols, and flavonoids, which can differ between extracts depending on the extraction method. In particular, the diterpenes carnosol and carnosic acid are two of the most abundant phytochemicals found in rosemary, and these compounds contribute up to 90% of the anti-oxidant potential of the herb. Additionally, several in vivo studies have shown that rosemary administration has a positive impact on gastrointestinal (GI) health through decreased oxidative stress and inflammation in the GI tract. The objective of this review is to highlight the food preservative potential of rosemary and detail several studies that investigate rosemary to improve in vivo GI health.

Effect of date fruit waste extract as an antioxidant additive on the properties of active gelatin films

In this work, date-fruit syrup waste extract (DSWE) was used as an antioxidant additive to develop active gelatin films with enhanced food preservation properties. The effect of DSWE content (5, 10, 15, and 25 wt%) on the mechanical, physical, and antioxidant properties of the gelatin films were analyzed. Total phenolic content and antioxidant assay analysis revealed that the active compounds in blend films are highly migrated to the aqueous phase than the fatty medium. In the canola oil stability studies, gelatin/25 wt% DSWE film immersed oil sample exhibited low peroxide (POV) and p-anisidine (PV) values of 28.6 and 7.1, respectively, compared to the control oil (POV = 41.7 and PV = 13.1) in the air atmosphere and 45 °C for 30 days. Totox values of canola oil samples were decreased as a function of DSWE content in the films, indicating that polyphenols in DSWE are significantly resistant to oil's lipid oxidation.

Essential oils: A promising eco-friendly food preservative.

Essential oils (EOs) are natural, volatile and aromatic liquids extracted from special plants. EOs are complex mixture of secondary metabolites (terpenes, phenolic compounds, alcohol). EOs possess a wide range of biological activities including antioxidant, antimicrobial and anti-inflammatory ones. Particularly, EOs exhibit pronounced antibacterial and food preservative properties that represent a real potential for the food industry. Numerous EOs have the potential to be used as a food preservative for meat and meat products, vegetables and fruits as well as for dairy products. The main obstacles for using EOs as food preservatives are their safety limits, marked organoleptic effects and possible contamination by chemical products such as pesticides. This review aims to provide an overview of current knowledge about EOs food preservative properties with special emphasis on their antibacterial activities and to support their uses as natural, eco-friendly, safe and easily biodegradable agents for food preservation.

Biochemical Profile of Olive Leaves Grown in "Olive Valley" Pakistan

This study was designed to determine the best olive variety for cultivation in Pakistan. The leaves of eight locally grown varieties were analyzed for levels of moisture, total solids, ash, fat, fibre, protein, K, Ca, Mg, Na, Fe, Mn, Zn and Cu levels. Leaves were then subjected to solvent extraction with each of water ratio in, 75% ethanol, 75% methanol, 95% ethanol and 95% methanol. The extract yield was significantly highest for 75% ethanol extract of all varieties. Significantly highest polyphenol and flavonoid contents were examined for Gemlik leaves extracted with 75% ethanol. We recommend cultivation of Gemlik in Pakistan and extraction of bioactive compounds from olive leaves will be the most efficient with a binary solution of 75% ethanol in water. Further studies should be planned to assess antioxidant, antimicrobial and food preservation properties of olive leaf extract from locally grown varieties.

Characterization of bio-based plastic made from a mixture of Momordica charantia bioactive polysaccharide and choline chloride/glycerol based deep eutectic solvent

Momordica charantia bioactive polysaccharide (MCBP) was used as an alternative source for the production of bio-based plastics (BPs) with choline chloride/glycerol-based deep eutectic solvent (DES) as a plasticizer. In this study, MCBP was initially extracted using 0.1 M citric acid at temperature 80 °C for 2 h, precipitated using ethanol, and then lyophilized. Subsequently, seven BPs were prepared: MCBP without plasticizer (MCBP), with 1% (w/w) of glycerol (MCBP-G), or with 1% (w/w) of DES at different choline chloride/glycerol molar ratios (i.e. 1.5:1, 1:1, 1:1.5, 1:2, and 1:3). The properties of these BPs were then investigated. Results showed that the tensile strains, stresses and moduli were in the range of 1.3–13.3%, 4.8–19.1 MPa and 132–2487 MPa, respectively. The melting temperatures were found in the range of 92.6–111.4 °C whereas the moisture absorptions and water vapour transmission rates (WVTR) of BPs were 1.4–6.5% and 3.6–5.4 mg/m2·s, respectively. The results also showed that these BPs exhibited bioactivities, such as microbial inhibitory activity (19.5–32.3 mm), free radical scavenging activity (10.3–18.3%) and ferric reducing antioxidant power (FRAP, 16.1–20.0 mM). In addition, it was observed that using DES as a plasticizer had improved the properties of BP, such as tensile strain (354.7–937.5%), melting temperature (4.6–20.3%), radical scavenging activity (0.6–88.6%), FRAP (0.9–18.7%) and antimicrobial activity (12.3–33.6%) compared to MCBP, due to the fact DES has caused different degrees of plasticization via hydrogen bonds and ionic bonds with the polymer chains, and induced a lower pH condition. Therefore, it was suggested that these BPs with DES could contribute to food preservation properties.

HPLC와 DPPH radical 소거능 측정 방법의 결합에 의한 약용 식물 추출물의 항산화 활성 비교

Natural anti-oxidative compounds have important disease prevention and food preservation properties, in addition to anti-bacterial, anti-inflammation, anti-cancer, and skin whitening effects. High-performance liquid chromatography (HPLC), with an ultra vilolet (UV) detector coupled to a reverse phase C18 column and an online measurement system for 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radicals, was used to search for potent antioxidative compounds in crude extracts. The online HPLCDPPH assay was then applied to confirm antioxidative compounds in water extracts from Radix of Pueraria lobata, Rhizoma of Zingiber officinale, Fructus of Chaenomeles sinensis, Cortex of Ulmus pumila, and Radix of Astragalus membranaceus. To determine the yields of the extracts, the Brix% of each extract solution was measured using a refractometer. When the relative DPPH radical scavenging ability values of the water extracts were compared with those of a positive control (ascorbic acid), the water extracts of P. lobata, C. sinensis, and U. pumila were 7.77%, 4.71%, and 4.19%, respectively. The results suggest that this method provides a useful assay for rapid measurement of DPPH radical scavenging abilities and conformation of antioxidative compounds in natural products. Moreover, it can reduce the time spent on the separation of active compounds from natural materials, such as medicinal plants, in addition to the use of reagents for separation.