Antimicrobial Effect of Bacteriocin KU24 Produced by Lactococcus lactis KU24 against Methicillin‐Resistant Staphylococcus aureus

Bacteriocin KU24 produced by Lactococcus lactis KU24 exhibited an inhibitory effect against methicillin‐resistant Staphylococcus aureus (MRSA). Bacteriocin KU24 was inactivated by protease XIV, showing that it has a proteinaceous nature on S. aureus ATCC 33591. Also, bacteriocin KU24 exhibited a strong heat stability (121 °C for 15 min) and pH stability (pH 3 to 9). The mode of inhibition was determined for S. aureus ATCC 33591 by treatment of 0, 250, and 500 AU/mL of bacteriocin KU24. S. aureus ATCC 33591 was inhibited by added bacteriocin KU24, while control was increased. The cell membranes of S. aureus ATCC 33591 were damaged with treatment of 500 AU/mL of bacteriocin KU24. Also, bacteriocin KU24 inhibited the occurrence of mecA gene, the methicillin resistance gene in S. aureus ATCC 33591. Bacteriocin KU24 was purified by C₁₈ Sep‐Pack column, cation exchange chromatography, and gel filtration chromatography, and molecular mass is approximately 6.5 kDa by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis. These results demonstrate that bacteriocin KU24 can be used as an alternative antimicrobial agent for the treatment of infection of MRSA in the food industry.     

Antibacterial mechanism of adzuki bean seed coat polyphenols and their potential application in preservation of fresh raw beef

The monomeric phenolic components of adzuki bean seed coat polyphenols (ABSCPs) were analysed, and their antibacterial activity and mechanism against two tested bacteria (Escherichia coli ATCC8797 and Staphylococcus aureus ATCC12600) were evaluated for their potential application in preservation of fresh raw beef. ABSCP contained 13 kinds of monomeric phenols, and the minimum inhibition concentration (MIC) of ABSCP against E. coli and S. aureus was 1250 and 625 μg ml⁻¹, respectively. The mechanism of ABSCP against E. coli and S. aureus was associated with increased cell protein and nucleic acid leakage, increased cell membrane potential, decreased intracellular ATP concentration and morphological changes in bacterial cell. In addition, ABSCP with whey protein isolate (WPI) was applied to fresh raw beef and this remarkably retarded microbial growth by maintaining the total microbial quality below the acceptable limit of 6 lg CFU g⁻¹ for 14 days. Lower pH and total volatile base nitrogen values were observed in the coated samples during refrigerated storage (4 °C). As a result, we found that ABSCP, as a natural food bacteriostatic agent, can effectively inhibit the growth of E. coli and S. aureus and combined with WPI to apply to fresh raw beef to extend its shelf life.     

Daphne oleoides: An alternative source of important sesquiterpenes

This study was targeted to characterize the chemical composition and antibacterial properties of Daphne oleoides subsp. oleoides essential oil. The essential oil was analyzed and quantified by gas chromatography and gas chromatography/mass spectrometry. Additionally, the broth dilution method was used to evaluate its antibacterial activity against Bacillus cereus (ATCC 11778), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Streptococcus faecalis (ATTC 29212), Escherichia coli (ATCC 25922), Proteus mirabilis (ATCC 25933), Proteus vulgaris (ATCC 13315), Pseudomonas aeruginosa (ATCC 27853), and Salmonella typhi Ty2 (ATCC 19430). Seventy-nine compounds were identified, representing 95.2% of the total oil. Nootkatone (18.5%), nootkatin (12.1%), and daphnauranol C (11.7%) were determined as the main constituents in the oil. Oxygenated sesquiterpenes were dominating in the oil (43.0%), followed by fatty acid derivatives (13.7%) and carbonylic compounds (9.6%). The minimal inhibitory/bactericidal concentrations of essential oils of D. oleoides were in the range from 25–100 μg/mL, which can be considered as high activity in comparison with the reference antibiotic which was active in the rangefrom 3.12–100 μg/mL. The greatest minimal inhibitory concentration value was determined as 25 µg/mL against both two Bacillus strains and S. epidermidis, B. cereus, B. subtilis, and S. aureus were the most sensitive strains against essential oils when compared with the minimal inhibitory concentrations of control antibiotic. Consequently, Daphne oleoides subsp. oleoides can be exploited as a source of natural antibacterial agents and nootkatone for the pharmaceutical, food, and agricultural industries.     

Supercritical fluid extraction of antioxidant and antimicrobial compounds from Laurus nobilis L. Chemical and functional characterization

Extraction of laurel leaves by using supercritical carbon dioxide was carried out on a supercritical fluid (SF) pilot-scale plant. The extraction pressure and temperature were set to 250 bar and 60°C, respectively, using a 4% of ethanol as modifier. The employed apparatus, owing to a two-stage separation, allowed us to obtain two different fractions (F1 and F2), whose antioxidant and antimicrobial activities were investigated. Two different methods, β-carotene bleaching test and DPPH^• free radical–scavenging assay, were carried out to determine the antioxidant activity. Moreover, antimicrobial activity of laurel fractions was tested against Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa ATCC 10145, Escherichia coli ATCC 11775, Candida albicans ATCC 60193 and Aspergillus niger ATCC 16404. Minimum inhibitory concentration (MIC) and minimal bactericidal and fungicidal concentration (MBC) were obtained. Both fractions showed a similar antioxidant activity, although it was slightly higher for the fraction recovered in separator 2. However, antimicrobial activity against the microorganisms tested was only found when fraction 2 was used. Staphylococcus aureus was the most sensitive microorganism to this fraction, with maximal inhibition zones (25 mm) and the lowest MBC values (1.25 mg/ml), whereas the least susceptible was the fungi Aspergillus niger. In order to determine the compounds responsible for the antimicrobial activity, fraction 2 was analysed by GC–MS; results obtained showed that most of the compounds identified in the supercritical extract have been previously described to show antimicrobial activity; among them, the major compound found in the supercritical extract corresponded to a sesquiterpene lactone of the germacrolide type (6-epi-desacetyllaurenobiolide) previously described in laurel.     

银杏种仁蛋白分离纯化及其抑菌活性

从银杏种仁中分离纯化具有抑菌活性的蛋白质,并分析其抑菌活性。结合抑菌活性分析,采用硫酸铵分级盐析、透析、纤维素DE-52阴离子交换柱层析及Sephadex G-75凝胶过滤柱层析对银杏种仁蛋白（Ginkgo bilobaseed protein,GBSP）进行分离纯化,得到一种抑菌蛋白GBSPⅠ-A。十二烷基磺酸钠-聚丙烯酰胺凝胶电泳（sodiumdodecyl sulfate polyacrylamide gel electrophoresis,SDS-PAGE）检测结果显示,该蛋白呈单一条带,其分子质量约为42.80 kD;Superdex G-75柱层析结果显示GBSPⅠ-A呈单一对称峰,高效凝胶渗透色谱测定其分子质量为39.32 kD;该蛋白对肺炎克雷伯氏菌、金黄色葡萄球菌、戴尔有孢圆酵母及黑曲霉的最小抑菌浓度（minimum inhibitory concentration,MIC）分别为20、20、20、12 mg/mL。     

Antimicrobial activity of greater galangal [Alpinia galanga (Linn.) Swartz.] flowers

Using the agar disc diffusion method, the potential antimicrobial activity of edible galangal [Alpinia galanga (Linn.) Swartz.] flower against Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Shigella, and the effects of different drying methods and solvent types on the flowers’ antimicrobial activity were investigated. Oven-dried ethanol (OD Ethanol) extract from galangal flower was the most effective against S. aureus with inhibition zone of about 26–31 mm and the minimum inhibitory concentration (MIC) ranging from 0.352–0.547 mg/mL. No antimicrobial activity was observed on E. coli O157:H7 and Salmonella. Overall antimicrobial activity of oven-dried samples extracted with ethanol (OD Ethanol) was the highest with inhibition zone of 8.94 mm and MIC of 1.457 mg/mL. In contrast, freeze-dried samples extracted with ethanol (FD Ethanol) exhibited the lowest overall antimicrobial activity (7.05 mm and 2.470 mg/mL). This is the first report describing antimicrobial activity of galangal flowers against Grampositive S. aureus.     

Antimicrobial activity of bovine β-lactoglobulin against mastitis-causing bacteria

Bovine mastitis is one of the most economically deleterious diseases affecting dairy herds and results from an infection of the udder by pathogenic microorganisms such as Staphylococcus aureus, Streptococcus uberis, and Escherichia coli. The mammary gland is capable of preventing and combating bacterial infection by means of a complex network of innate and adaptive immune mechanisms. Lactoferrin is an 86-kDa protein with antibacterial activity that plays a role in the mammary gland's defense against infection. β-Lactoglobulin (β-LG) is an 18-kDa protein that is present in most mammals but is notably absent in humans, rodents, and lagomorphs. Different genetic variants of this protein exist, with β-LG A and β-LG B being the most common. In spite of being well studied, the biological function of β-LG is not thoroughly understood, and most noticeably, no reports exist on the effects of the native protein on bacterial growth. Hence, the objective of this study was to assess the potential antibacterial activity of β-LG against mastitis agents. To do this, we purified β-LG from normal bovine milk using a mild, nondenaturing method and performed in vitro growth inhibition assays with Staph. aureus, E. coli, and Strep. uberis. β-Lactoglobulin inhibited the growth of Staph. aureus and Strep. uberis but had no effect on E. coli. The antimicrobial activity against Staph. aureus and Strep. uberis was concentration dependent and was elicited by the intact protein because Tricine-sodium dodecyl sulfate-PAGE and analytical gel filtration chromatography did not reveal the presence of short degradation peptides. Analysis of the genetic variants of β-LG showed that β-LG A has higher inhibitory activity against Staph. aureus and Strep. uberis than β-LG B. Coincubation of β-LG and lactoferrin resulted in an augmented antibacterial activity against Staph. aureus, suggesting an additive effect of the proteins. This result, along with the proteins’ complementary spectrum of action, suggests that β-LG and lactoferrin may complement each other in the mammary gland's defenses against bacterial infection.     

Identification and Functional Characterization of Cysteine Protease from Nine Pear Cultivars (Pyrus pyrifolia)

This study was performed to compare the total protein and protease content among the whole fruit, flesh, and peel of nine different pear cultivars. Pear proteases were functionally characterized with respect to three enzyme assays. Proteases from pears were further identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, in gel activity staining, and matrix assisted laser desorption/ionization-time of flight mass spectrometry analysis. Flesh from Whasan, Nikita, and Hanareum cultivars contained relatively more total protein and protease and showed high enzyme activities, while Chuwhang contained the lowest amount of protein and protease activity. Protease content and enzyme activities found in the pear flesh or whole fruits were two to six times higher than those in the pear peel. Pear cultivars contained one or two protease bands with molecular weights of 36 kDa and/or 38k Da. The larger band was further identified as a cysteine proteinase with 70% homology to the pear cysteine protease from Pyrus pyrifolia.     

Effect of juice processing on cranberry antibacterial properties

The effects of the industrial juice process on the ability of neutralized cranberry samples and extracts (polar, apolar and anthocyanins) to inhibit the growth of Enterococcus faecium resistant to vancomycin (ERV), Escherichia coli O157:H7 EDL 933, E. coli ATCC 25922, Listeria monocytogenes HPB 2812, Pseudomonas aeruginosa ATCC 15442, Salmonella Typhimurium SL1344 and Staphylococcus aureus ATCC 29213 were investigated. The juice process appeared to have a general enhancing effect on the antibacterial properties of cranberry polar and anthocyanin extracts. The lowest minimum inhibitory concentrations (MICs) (1.80–7.0 μg phenol/well) were obtained when S. aureus, S. Typhimurium, and ERV were exposed to the juice concentrate. The growth of P. aeruginosa, L. monocytogenes, E. coli ATCC, and E. coli O157:H7 was not inhibited by the juice concentrate, but did show sensitivity (maximal tolerated concentrations of 0.007–0.4 μg phenol/well). The lowest MICs (22.6–90.5 μg phenol/well) for P. aeruginosa, S. aureus, S. Typhimurium, and ERV were observed when they were exposed to the cranberry anthocyanin extract obtained from cranberry pomace. The results also showed a negative effect of the juice process on the antibacterial properties of the cranberry apolar extracts: the one obtained from frozen cranberries was most efficient against P. aeruginosa, S. aureus, L. monocytogenes and S. Typhimirium (MIC of 45.50 μg phenol/well). The tested bacteria showed the greatest resistance toward the cranberry extracts obtained from the mash and the macerated and depectinized mash.     

Antibacterial activity and mechanism of a novel bacteriocin produced by Lactiplantibacillus plantarum against Escherichia coli and Staphylococcus aureus

The purpose of the study was to explore the antibacterial effect and mechanism of a novel bacteriocin of Lactiplantibacillus plantarum (L. plantarum) against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial activity was determined by the Oxford cup method, and the dynamic growth curves were conducted with continuous shaking incubation. The result showed that the bacteriocin was a protein or protein-like antibacterial substance susceptible to pepsin and trypsin. And it had good antibacterial activity, pH stability, thermostability and enzyme treatment stability against E. coli and S. aureus. The SEM, flow cytometry and nucleic acid leakage showed that the bacteriocin disrupted the cell structures of the two bacteria by damaging cell walls and cell membranes. An agarose gel electrophoresis and SDS-PAGE analysis showed that the bacteriocin inhibited DNA replication and interfered with the protein formation, which resulted in the inhibition of the two bacteria's growth. Therefore, the use of the L. plantarum bacteriocin might be a promising biocontrol strategy to inhibit the pollution of E. coli and S. aureus simultaneously in foods.     

Antibacterial properties of honey produced by Melipona beecheii and Apis mellifera against foodborn microorganisms

The aim of this study was to determine the antibacterial activity in vitro of Melipona and Apis honey against various foodborne microorganisms. The results of qualitative test showed that Melipona honey inhibited both Staphylococcus aureus ATCC25923 and H08M06 strains and both Escherichia coli ATCC35922 and H12K06 strains. Apis honey inhibited both E. coli ATCC35922 and H12K06 strains and S. aureus ATCC25923 strain. Minimum inhibitory concentrations of Melipona honey (5–16%, w/v) were lower than those of Apis honey (15–31%, w/v). This study demonstrated that the antibacterial potency of Melipona honey could be a new alternative for controlling foodborne illness.     

Differential inactivation of food poisoning bacteria and Lactobacillus sp. by mandelic acid

Microbicides are used to eliminate pathogenic bacteria, but they can also eliminate beneficial and normal bacteria. This study provides antimicrobial information of mandelic acid (MA) prior to its widespread use. The MA susceptibilities of Lactobacillus sp. and pathogens were determined by dilution method based on NCCLS protocol. The concentration of MA at 5.0 mg/mL inhibited 90% of the Lactobacillus sp., whereas a 1.25 mg/mL concentration inhibited the following pathogenic bacteria strains: Listeria monocytogenes KCTC3710, Yersinia enterocolitica ATCC23715, and Shigella sonnei ATCC9290. The minimal inhibitory concentration (MIC) for Escherichia coli O157:H7, Salmonella enteritidis KCTC12400, Salmonella gallinarum ATCC9148, Salmonella typhimurium ATCC29631, and Staphylococcus aureus KCCM40881 was at 2.5 mg/mL. These pathogens were also inhibited by addition of 1.0 M NaCl in 2 mg/mL MA solution (pH 5.0), while lactobacilli were not affected. These results indicate that MA can prevent disease and food poisoning when applied as a disinfectant in food industry, hospitals, and public places.     

Purification,characterization, and mode of action of a novel bacteriocin BM173 from Lactobacillus crustorum MN047 and its effect on biofilm formation of Escherichia coli and Staphylococcus aureus

There is an increasing demand for dairy products, but the presence of food-spoilage bacteria seriously affects the development of the dairy industry. Bacteriocins are considered to be a potential antibacterial or antibiofilm agent that can be applied as a preservative. In this study, bacteriocin BM173 was successfully expressed in the Escherichia coli expression system and purified by a 2-step method. Furthermore, it exhibited a broad-spectrum antibacterial activity, high thermal stability (121°C, 20 min), and broad pH stability (pH 3–11). Moreover, the minimum inhibitory concentration values of BM173 against E. coli ATCC 25922 and Staphylococcus aureus ATCC 25923 were 14.8 μg/mL and 29.6 μg/mL, respectively. Growth and time-kill curves showed that BM173 exhibited antibacterial and bactericidal activity. The results of scanning electron microscopy and transmission electron microscopy demonstrated that BM173 increased membrane permeability, facilitated pore formation, and even promoted cell lysis. The disruption of cell membrane integrity was further verified by propidium iodide uptake and lactic dehydrogenase release. In addition, BM173 exhibited high efficiency in inhibiting biofilm formation. Therefore, BM173 has promising potential as a preservative used in the dairy industry.     

Chemical Composition and Antimicrobial Activity of the Essential Oil from the Peel of Shatian Pummelo (Citrus Grandis Osbeck)

The chemical composition of the essential oil obtained from the peel of Shatian pummelo was analyzed by gas chromatography/mass spectrometry. Twenty-one components were identified. The monoterpenes and sesquiterpene hydrocarbons were the principal compound groups with 96.64% (w/w) of the total oil, among which, limonene was observed dominant (89.96 ± 1.64%), followed by β-myrcene (4.49 ± 0.38%), α-pinene (0.63 ± 0.05%), 3-carene (0.48 ± 0.04%), caryophyllene (0.47 ± 0.04%), and other minor constitutes. Esters, alcohols, ketones, aldehydes, and ether represented 3.15% of the total oil. Results by the disc diffusion method and minimum inhibitory concentration determination method showed that the essential oil contained a wide-spectrum antimicrobial activity against Penicillium chrysogenum ATCC 10106, Bacillus subtilis ATCC 21616, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922, with their inhibition zones ranging from 8.27 ± 1.07 mm to 20.71 ± 1.50 mm. The MIC values were ranging from 4.69 to 37.50 μL/mL. However, no inhibition effect was observed on the Aspergillus niger ATCC 16888.     

Potential roles of essential oil and organic extracts of Zizyphus jujuba in inhibiting food-borne pathogens

This study was undertaken to examine the chemical compositions of essential oil and tested the efficacy of oil and organic extracts from seeds of Zizyphus jujuba against food-borne pathogens. The chemical compositions of the oil was analysed by Null. Twenty three compounds representing 91.59% of the total oil were identified. The oil (5 μl of 1:5 (v/v) dilution of oil with methanol) and extracts of hexane, chloroform, ethyl acetate and methanol (300 μg/disc) of Z. jujuba displayed a remarkable antibacterial activity against Staphylococcus aureus (ATCC 6538 and KCTC 1916), Listeria monocytogenes ATCC 19166, Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa KCTC 2004, Salmonella typhimurium KCTC 2515 and Escherichia coli ATCC 8739. The scanning electron microscopic studies also demonstrated the effect of essential oil on the morphology of Staph. aureus ATCC 6538 at the MIC value, along with the potential effect on cell viabilities of the tested bacteria.     

Antimicrobial Effect of Sour Pomegranate Sauce on Escherichia coli O157 : H7 and Staphylococcus aureus

Pomegranate sauce is one of the most popular pomegranate products produced in Turkey. This study was conducted to determine the minimum inhibitory concentrations (MICs) of both traditional and commercial sour pomegranate sauce samples on Staphylococcus aureus (ATCC 25923) and Escherichia coli O157 : H7 (ATCC 43895). The initial microflora of the pomegranate sauce samples was determined by performing the enumerations of total aerobic mesophilic bacteria, yeast and mold, S. aureus, E. coli, and the determination of Salmonella spp. MIC tests were applied to the neutralized and the original (unneutralized) sour pomegranate sauce samples in order to put forth the inhibition effect depending on low pH value. It was found that inhibitory effect of the traditional and the commercial samples, except one sample, on pathogens was not only due to the acidity of the products. The results of MIC tests indicated that although both traditional and commercial samples showed a considerable inhibitory effect on test microorganisms, the traditional pomegranate sauce samples were more effective than the commercial ones.     

Antimicrobial activity of <Emphasis Type="Italic">Myagropsis myagroides</Emphasis> and interaction with food composition

Ethanol extract of Myagropsis myagroides (MMEE) has substantial antimicrobial activity against Gram-positive bacteria and some of the yeasts. The minimum inhibitory concentration (MIC) of MMEE ranged from 0.0625 to 0.125 mg/mL for Bacillus subtilis, Listeria monocytogenes, and Clostridium perfringens. Chloroform fraction obtained through liquid-liquid extraction possessed the strongest antimicrobial activity, and was separated by silica gel column chromatography. Among 22 of subfraction, CH4 showed the strongest activity (4–8 times MIC of the crude extract). The antimicrobial activity of CH4 to Staphylococcus aureus was reduced at high concentrations of starch, but the bactericidal effect of CH4 was maintained at 1 and 5% starch model media. The efficacy of CH4 against S. aureus diminished in the presence of >5% beef extract and >1% soybean oil. In acute toxicity test, no mortalities occurred in mice administered 5 g/kg body weight of MMEE over 2 weeks observation.     

Analysis and the potential applications of essential oil and leaf extracts of <Emphasis Type="Italic">Silene armeria</Emphasis> L. to control food spoilage and food-borne pathogens

The aim of this study was to analyze the chemical composition of essential oil isolated from the floral parts of Silene armeria L. by hydrodistillation and to test the efficacy of essential oil and the various leaf extracts against a diverse range of microorganisms comprising food spoilage and food-borne pathogenic bacteria. The chemical composition of essential oil was analyzed by the GC–MS. It was determined that 28 compounds, which represented 89.03% of total oil, were present in the oil. The oil contained mainly methylamine (21.48%), β-butene (17.97%), α-butene (46.40%), coumaran (0.22%), eugenol (0.21%), α-humulene (0.07%), farnesol (0.05%) and linalool (0.12%). The essential oil (5 μl/ml, corresponding to 1,000 ppm/disc) and various leaf extracts of methanol, ethyl acetate, chloroform and hexane (7.5 μl/ml, corresponding to 1,500 ppm/disc) exhibited promising antibacterial effect against Bacillus subtilis ATCC6633, Listeria monocytogenes ATCC19166, Staphylococcus aureus KCTC1916, S. aureus ATCC6538, Pseudomonas aeruginosa KCTC2004, Salmonella typhimurium KCTC2515, Salmonella enteritidis KCTC2021, Escherichia coli O157-Human, E. coli ATCC8739, E. coli O57:H7 ATCC43888 and Enterobacter aerogenes KCTC2190. The zones of inhibition of different concentrations of essential oil and the various leaf extracts against the tested bacterial pathogens were found in the range of 10–19 and 7–13 mm, respectively, along with their respective MIC values ranging from 125 to 1,000 and 250–2,000 μg/ml. Also, the essential oil had a potential effect on the viable count of the tested bacteria. The results of this study suggest that the essential oil and leaf extracts derived from S. armeria could be used for the development of novel types of antibacterial agents to control food spoilage and food-borne pathogens.     

Preparation, identification, structure, and in vitro anti-obesity effects of protease inhibitors isolated from potato fruit juice

In this study, potato protease inhibitors (PPI) were obtained from industrial potato fruit juice (PFJ) using membrane separation method and ion exchange chromatography. The molecular weight distribution, families, structural characterization, and in vitro anti-proliferative activity of PPI were evaluated in this paper. The molecular weight distribution of PPI was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI–TOF-MS). The inhibitor families were identified using high-performance liquid chromatography/mass spectrometry. The structures of the isolated PPI were studied by circular dichroism and fluorescence spectroscopy. Anti-proliferative activity of PPI on 3T3-L1 preadipocytes was investigated by MTT method. The results suggest that ultrafiltration (UF) was more suitable for the isolation of crude proteins from PFJ than nanofiltration. The PPI purified from UF freeze-dried powder were mainly focused on proteins in the region of relative molecular masses (Mr) 20 × 10³ to 22 × 10³ with a few low molecular weight proteins, containing protease inhibitor, protease inhibitor II, aspartic protease inhibitor, and other serine protease inhibitor families. The major conformation of PPI was β-structure, and the tryptophans were mainly located in hydrophobic environments. Furthermore, the structure changed significantly when the temperature reached 80 °C. Moreover, PPI were able to inhibit the proliferation of 3T3-L1 preadipocytes with a 50 % inhibitory concentration of 343.51 μg/mL. Therefore, PPI may have a potential implication in anti-obesity foods in the future.     

Eco-friendly modification and antibacterial functionalization of viscose fabric

Pretreatment of viscose fabric with monochlorotraizinyl β-cyclodextrin (MCT-βCD), as an eco-friendly modifying agent, is accompanied by creation of hosting nanocavities onto the cellulose structure thereby enabling inclusion of certain antibacterial agents namely triclosan, as a classic agent, and AgNO₃, as well as bioactive agents like green tea extract and Aloe vera gel. The efficiency of hosting the nominated antibacterial agents to confer antibacterial functionality is governed by the type of modification method and follows the decreasing order: exhaustion > pad-steam fixation > pad-dry-cure. The imparted antibacterial functionality of MCT-βCD-loaded fabric samples is determined by type of the hosted antibacterial agent into cavities of βCD and follows the decreasing order: AgNO₃ > green tea extract > triclosan > Aloe vera gel. Nitrogen content analysis, FTIR spectra, SEM image and EDX spectrum of Ag-loaded fabric sample confirmed the impact of suggested treatment sequence on the chemical and surface properties of the functionalized viscose fabric. The results also demonstrate that the imparted antibacterial activity against S. aureus (G+ve) and E. coli (G?ve) bacteria slightly decreased after 15 washing cycles.