API ZYM Kit Research Articles

Characterization of berry by-products as fermentable substrates: Proximate and phenolic composition, antimicrobial activity, and probiotic growth dynamics

Strawberry, raspberry, blueberry, and blackberry by-products were analyzed for proximate composition, bioactive compounds, antimicrobial activity, and fermentability by 13 potential probiotic strains. Proximate composition was assessed using AOAC methods and gas chromatography, individual phenolic compounds were quantified through UHPLC-PDA, and antimicrobial activity was determined using the broth microdilution technique. Berry bagasses were then added as carbon source in growth media, being alternatively washed to remove simple sugars, to evaluate the effect of the bagasse on microbial growth and enzymatic production through the API ZYM kit. Glucose and fructose levels ranged from 8.9 to 24.3 g/100 g dry weight, with minor amounts of sucrose and myo-inositol. Eighteen phenolics were quantified, with high amounts of ferulic acid, 4-hydroxybenzoic acid, cyanidin 3-glucoside, and petunidin 3-glucoside. Blackberry bagasse showed the highest pathogen inhibition (71.6–96.5%). Lacticaseibacillus rhamnosus GG and Lentilactobacillus kefiri BIOTEC014 succeeded on media with strawberry or blueberry bagasse as carbon source. The washing of strawberry and blueberry bagasses reduced growth (47–78%) but enhanced enzymatic activity, particularly β-glucosidase in BIOTEC014. These findings suggest that berry bagasses can serve as valuable functional ingredients for food and pharmaceutical applications.

Enzyme characterization of lactic acid bacteria isolated from duck excreta.

The production of lignocellulosic biomass waste in the agricultural sector of Indonesia is quite high annually. Utilization of lignocellulosic biomass waste through fermentation technology can be used as feed and biofuel. Fermentation technology requires the involvement of micro-organisms such as bacteria (lactic acid bacteria or LAB). LABs can be isolated from various sources, such as duck excreta. However, there have not been many reports of LAB from duck excreta. The present study aimed to characterize LAB enzymes isolated from duck excreta and obtain LAB enzymes with superior fermentation properties. A total of 11 LAB cultures obtained from duck excreta in Yogyakarta, Indonesia, were tested. Enzyme characterization of each LAB was performed using the API ZYM kit (BioMérieux, Marcy-I'Etoile, France). The bacterial cell suspension was dropped onto the API ZYM™ cupule using a pipette and incubated for 4 h at 37°C. After incubation, ZYM A and ZYM B were dripped onto the API ZYM cupule, and color changes were observed for approximately 10 s under a strong light source. Esterase activity was moderate for all LABs. The activity of α-chymotrypsin, β-glucuronidase, α-fucosidase, and α-mannosidase was not observed in a total of 10 LAB. The phosphohydrolase and amino peptidase enzyme activity of seven LABs was strong. Only six LAB samples showed protease activity. The glycosyl hydrolase (GH) activity was observed in a total of 8 LAB, while the activity of 2 LAB was strong (Lactococcus lactis subsp. lactis K5 and Lactobacillus brevis M4A). A total of 2 LABs have superior properties. L. lactis subsp. lactis K5 and L. brevis M4A have a high potential to be used in fermentation. They have the potential for further research, such as their effectiveness in fermentation, lignocellulose hydrolysis, feed additives, molecular characterization to detect specific enzymes, and their specific activities.

Effect of oxygen deficiency on organic matter decomposition during the early stage of composting.

This study aimed to elucidate the recovery of organic matter decomposition after oxygen deficiency in the early stage was replaced by aerobic conditions during composting. Oxygen deficiency at the early stage was created by supplying nitrogen gas into the composting for 3days (LN3dA) and 5days (LN5dA). Subsequently, air was introduced until the end of composting instead of nitrogen gas. Runs LN3dA and LN5dA had lower organic matter decomposition by 10% and 19%, respectively, compared with fully aerobic composting (LA) after oxygen deficiency was changed to aerobic conditions. Compared with fully aerobic composting, composting with oxygen deficiency at the early thermophilic stage had a different bacterial community, as analyzed by high-throughput sequencing. During vigorous organic matter decomposition, Bacillus was dominant in Run LA, whereas Caldibacillus proliferated in Runs LN3dA and LN5dA. Bacillus thermoamylovorans, Bacillus arbutinivorans, and Bacillus kokeshiiformis were hypothesized to be inhibited by Caldibacillus. Moreover, dissimilarity analysis indicated that different bacterial communities remained until the end of composting, which could be a reason for the incomplete recovery of organic matter decomposition. As analyzed by the API-ZYM kit, the enzymatic activities were also different between all composting runs. One of the characterized enzymes, α-galactosidase, displayed low activity during oxygen deficiency and could not achieve high activity with sufficient oxygen until composting was completed. Overall, our study showed that oxygen deficiency at the early thermophilic stage caused incomplete recovery of organic matter decomposition.

Formation of viable but nonculturable state of Staphylococcus aureus under frozen condition and its characteristics

Viable but nonculturable (VBNC) state of microorganisms has attracted much attention due to its characteristics, including the difficulty in detection by culture-based methods, virulence retention, high resistance, and so on. As a foodborne pathogen, Staphylococcus aureus is widely distributed, and has been found to enter the VBNC state under some environmental stresses, posing a potential threat to human health. Freezing is a common condition for food storage. This study investigated whether citric acid, a common food additive, could induce S. aureus into the VBNC state at −20 °C. By measuring the number of culturable and viable cells, it was found that S. aureus entered the VBNC state after 72 days of induction in citric acid buffer at −20 °C. The VBNC cells were then successfully resuscitated at 37 °C in trypsin soybean medium (TSB) with or without heat shock treatment, and TSB supplemented with sodium pyruvate and Tween 80 after 48 h. Heat shock resulted in an excellent resuscitation effect. Observed by transmission electron microscopy, the internal structure of VBNC cells was found markedly changed, compared with that of exponential phase cells. API ZYM kit was used to compare the intracellular enzyme activity of S. aureus in the exponential phase with that in the VBNC state. The results showed that the enzyme activity decreased significantly in VBNC cells, and that the VBNC cells were more resistant to simulated gastrointestinal fluid through flow cytometry analysis. Quantitative reverse-transcription polymerase chain reaction results suggested that the ability of adhesion and biofilm formation of VBNC cells might be decreased due to the down-regulation of related genes. However, it should not be ignored the recovery potential of biofilm-forming ability of VBNC cells caused by the high expression of sarA. In conclusion, S. aureus could be induced into the VBNC state in citric acid buffer at −20 °C, which showed changes in some biological characteristics and could resuscitate successfully by many conditions. Food industry needs to pay attention to the potential hazard by VBNC S. aureus under frozen conditions.

Bacteriocinogenic Bacillus spp. Isolated from Korean Fermented Cabbage (Kimchi)—Beneficial or Hazardous?

Bacillus velezensis ST03 and ST32, Bacillus amyloliquefaciens ST06 and ST109, and Bacillus subtilis ST08 were isolated from artisanal-produced kimchi and were identified based on 16S rRNA partial sequencing. DNA obtained from the investigated bacilli generated positive results for lichenicidin, iturin, subtilosin, and surfactin on a strain-specific basis. The strains were found to produce antimicrobial metabolites with activity levels ranging between 800 and 1600 AU/mL on a strain-specific basis, as determined against Listeria monocytogenes ATCC15313. Moreover, all tested strains in this study were still active after treatment with proteolytic enzymes, even with reduced inhibition zones compared to the controls, pointing to additional antimicrobial activity possibly related to a non-proteinaceous molecular structure. Most probably these strains may express surfactin as an additional factor in their complex antimicrobial activity. B. amyloliquefaciens ST09 and B. velezensis ST03 and ST32 were characterized as positive for β-hemolysis. B. subtilis ST08 was shown to be positive for hblC and nheC and B. amyloliquefaciens ST109 for nheB. B. amyloliquefaciens ST109 generated positive results for gelatinase activity. The ability of the studied Bacillus strains to metabolize different carbohydrate sources was done based on the API50CHB test, while the enzyme production profile was recorded by the APIZym kit. All studied strains were positive producers for biogenic amines production. Studied Bacillus spp. strains were resistant to some of the evaluated antibiotics, tested according to recommendations of CLSI and EFSA.

Phylogenetic Analysis and Extracellular Enzyme Profiles of Yeast Strains Isolated from Raspberry Fruits

Raspberry fruit contains phenolic compounds, flavones, flavonoids, vitamins, and antioxidant substances that are important properties for health and pharmacological sciences. Edible berries provide also a suitable habitat for the growth of various microorganisms. In this study, yeast biota associated with raspberry fruits was determined by molecular identification techniques. Raspberry fruits were collected from Çanakkale, Gelibolu (Gallipoli). Yeast strains were isolated and then identified by using the analysis of ITS1-5.8S-ITS2 rDNA gene sequences. The phylo-genetic analysis of all yeast strains was carried out by using the MEGA–X phylogenetic analysis tool. The extracel-lular enzyme profiles of identified yeast species were determined by the API-ZYM kit system. The distribution of yeast species on the raspberry fruits was determined as Hanseniaspora uvarum, Metschnikowia viticola, Aureo-basidium pullulans, and Metschnikowia pulcherrima. It was observed that yeast strains belong to Metschnikowia genus were dominant on raspberry fruits. All yeast strains in Metschnikowia genus showed different enzyme pro-files against seven extracellular enzymes. These enzymes may be the discriminatory enzymes for the yeast strains in the Metschnikowia genus. When the phylogenetic relationships among all yeast strains were investigated, all strains were divided into two main clades. While the first clade consists of only Metschnikowia genus, second clade includes H. uvarum and A. pullulans yeast species. Our results indicated that restriction patterns and also extracel-lular enzyme profiles could be utilized for differentiation of yeast strains within the genus. M. pulcherrima, H. uvarum, and A. pullulans can be used for industrial applications for future researches.

Biotransformation of Major Ginsenoside Rb1 to Rd by Dekkera anomala YAE-1 from Mongolian Fermented Milk (Airag).

Dekkera anomala YAE-1 strain separated from "airag" (Mongolian fermented mare's milk) produces β-glucosidase, which can convert ginsenoside Rb1 from Panax ginseng. Ginseng-derived bioactive components such as ginsenoside Rb1 have various immunological and anticancer activities. Airag was collected from five different mare milk farms located near Ulaanbaatar, Mongolia. YAE-1 strains were isolated from airag to examine the hydrolytic activities of β-glucosidase on Korean Panax ginseng using an API ZYM kit. Supernatants of selected cultures having β-glucosidase activity were examined for hydrolysis of the major ginsenoside Rb1 at 40°C, pH 5.0. The YAE-1 strain was found to be nearly identical at 99.9% homology with Dekkera anomala DB-7B, and was thus named Dekkera anomala YAE-1. This strain exerted higher β-glucosidase activity than other enzymes. Reaction mixtures from Dekkera anomala YAE-1 showed great capacity for converting ginsenoside Rb1 to ginsenoside Rd. The β-glucosidase produced by Dekkera anomala YAE-1 was able to hydrolyze ginsenoside Rb1 and convert it to Rd during fermentation of the ginseng. The amount of ginsenoside Rd was highly increased from 0 to 1.404 mg/ml in fermented 20% ginseng root at 7 days.

Isolation of lactic acid bacteria from kimchi and screening of Lactobacillus sakei ADM14 with anti-adipogenic effect and potential probiotic properties

A total of 225 lactic acid bacteria were isolated from 11 types of kimchi in South Korea and subjected to 16S rRNA gene sequence analysis. They were assigned as members of Lactobacillus sakei, Lactobacillus plantarum and Leuconostoc pseudomesenteroides. The strains belonging to the same species were analyzed by RAPD-PCR, and only one among strains showing the same band pattern were selected. Finally, 15 strains were selected as representatives for further study. Lipid accumulation inhibitory effects were observed in the strains tested. Lactobacillus sakei ADM14 reduced significantly intracellular triglyceride content on 3T3-L1 adipocytes and decreased the expression of five adipogenic marker genes, PPARγ, C/EBPα, aP2, FAS and CD36. L. sakei ADM14 was able to survive a strong acidity of pH 2 to 3 and 1.0% bile salts and showed better adhesion to Caco-2 cells than two reference strains. As an additional feature, resistances of strain ADM14 to some antibiotics were assessed in accordance with two guidelines, and it was confirmed using API ZYM kit that strain ADM14 does not produce harmful enzymes. These results showed that L. sakei ADM14 isolated from kimchi has the ability to inhibit adipogenesis in adipocytes and also has potential as a probiotic and alternative therapeutic supplement.

Assortments of Digestive Enzymes Induced in First Instar Larvae of Busseola fusca Feeding on Different Plants.

The stem borer Busseola fusca (Fuller) (Lepidoptera: Noctuidae) is an important pest of maize and sorghum in sub-Saharan Africa. This insect has oligophagous feeding habits, feeding mostly on maize and sorghum with a narrow range of wild Poaceous plant species. We hypothesised that first instar B. fusca larvae, the critical stage for successful establishment on a host plant, can establish and then grow on a particular plant as a result of induction of a complement of digestive enzymes that mediates host acceptance at first instars. A fast semi-quantitative analysis of potentially digestive enzymatic activities present in the first larvae previously fed for 4 days on leaves of host and non-host plants was performed using the API-ZYM kit system able to detect a multiplex of enzyme activities. Regardless of the plant species, the larvae exhibited higher activities of the carbohydrate metabolising enzymes than of aminopeptidases and proteases. In addition, highest activities of carbohydrates degrading enzymes were exhibited by larvae that consumed leaves of the most preferred plant species of B. fusca. Conversely, esterases were only detected in neonate larvae that consumed leaves of the less preferred and non-host plants. No alkaline phosphatase and lipase activities were detected. The significance of these results was discussed in terms of food requirements of first instar larvae when settling on a plant.

Diversity and enzymatic profiles of indigenous yeasts isolated from three types of palm wines produced in Côte d'Ivoire.

To investigate the genotypic diversity and enzymatic activity of yeast flora isolated from spontaneous fermenting saps of various palm trees (Borassus aethiopum, Raphia hookeri, Elaeis guineensis) tapped for palm wines. PCR-restriction fragment length polymorphism of ITS-5.8S rDNA combined to 26S rRNA gene and/or the partial ACT1 gene sequencing were applied for yeast characterization, and their enzymatic profiles assessed by using API ZYM kits. Thirteen genera and 23 species were identified, with the highest diversity (14 species) in raffia wine. Saccharomyces cerevisiae was dominant and common to all palm wines. Some potentially pathogenic yeasts were also isolated. The majority of tested strains displayed high amylo-peptidase, phosphatase, β-glucosidase and α-glucosidase activities and esterase activity. Diverse yeast species colonized palm wines, among which some were related to a specific type of wine and the majority of them have the ability to digest starch, sugar, protein or lipid. This study is a first step in understanding the significance of indigenous yeast flora of palm wines from Côte d'Ivoire. This knowledge is important as a tool for establishing new indigenous yeast collection; which could be used for the product quality improvement and as enzyme sources for biotechnological purposes.

The Potency Of Actinomycetes From Deepsea Sediment Of Makassar Strait For Producing Antimicrobial Substances

A research on antimicrobial screening of 36 actinomycetes isolated from marine sediment of Makassar Strait through Widya Nusantara Expedition (EWIN) in 2013 and 2014, enzymatic characterization of potential isolates, morphological characterization and metabolite profiling of selected isolates has been conducted. The antimicrobial screening was conducted using paper disc, enzymatic characterization was using APIZYM Kit, morphological characterization was using Scanning Electron Microscope. And metabolite profiling was using TLC and GCMS. Five isolates retrieved from this research had ability to inhibit the growth of the four microbial testing, Escherichia coli, Bacillus subtilis, Staphyllococcus aureus and Candida albicans, and the highest capability was shown by the MACMK-43 isolate that had 16S rRNA gene sequence similarity of 97.85% to Streptomyces violacens. The result showed that in GCMS, the active fraction was contained 4-amino-5-cyano-6-(4'methoxyphenyl)-1-methyl-2.3-dihydropyrrolo [2,3-B] pyridine which commercially used for bactericides and antihistamine.

국내 생막걸리에서 분리한 야생 효모의 특성

Wild yeasts were isolated from domestic non-sterilized Makgeolli and their fermentation characteristics were analyzed to select the best fermentation seed culture. A total of 65 yeast strains isolated yeasts from non-sterilized Makgeolli and Nuruk. In order to select fermentable strains, hydrogen sulfide, CO2 production ability, alcohol tolerance and aroma component production ability were analyzed. To screen the aromatic strains of isolates, media containing cerulenin, 5,5,5-trifluor-DL-leucine (TFL) and API ZYM kit were used. There were 36 strains resistance to cerulenin and all strains produced esterase and demonstrated tolerance against TFL. Hydrogen sulfide, which could degrade the quality of the fermented beverage, was not produced in 34 yeast. The correlation between alcohol tolerance of yeast and carbon dioxide production was analyzed by principal component analysis. YM22, YM31, YM32 and YM37 produced a total of 0.14-0.18 g/72 h of CO2 indicating high fermentability. Alcohol tolerance was measured by alcohol concentration. YM32, YM37 yeast had 20% alcohol tolerance. As a result, alcohol and flavor characteristics of wild yeast isolated from non-sterilized Makgeolli were analyzed and it was confirmed that yeast was suitable for the production of alcohol.

Characterization of Paenibacillus sp. MBT213 Isolated from Raw Milk and Its Ability to Convert Ginsenoside Rb1 into Ginsenoside Rd from Panax ginseng.

This study was conducted to isolate and characterize Paenibacillus sp. MBT213 possessing β-glucosidase activity from raw milk, and examine the enzymatic capacity on the hydrolysis of a major ginsenoside (Rb1). Strain MBT213 was found to have a high hydrolytic ability on ginsenoside Rb1 by Esculin Iron Agar test. 16S rDNA analysis revealed that MBT213 was Paenibacillu sp. Crude enzyme of MBT213 strain exhibited high conversion capacity on ginsenoside Rb1 into ginsenoside Rd proven by TLC and HPLC analyses. The API ZYM kit confirmed that Paenibacillu sp. MBT213 exerted higher β-glucosidase and β-galactosidase activity than other strains. Optimum pH and temperature for crude enzyme were found at 7.0 and 35°C in hydrolysis of ginsenoside Rb1. After 10 d of optimal reaction conditions for the crude enzyme, ginsenoside Rb1 fully converted to ginsenoside Rd. Ginseng roots (20%) were fermented for 14 d, and analyzed by HPLC showed that amount of ginsenoside Rb1 significantly decreased, while that of ginsenoside Rd was significantly increased. The study confirmed that the β-glucosidase produced by Paenibacillus sp. MBT213 can hydrolyze the major ginsenoside Rb1 and convert to Rd during fermentation of the ginseng. The β-glucosidase activity of this novel Paenibacillus sp. MBT213 strain may be utilized in development of variety of health foods, dairy foods and pharmaceutical products.

Potential probiotic Lactobacillus plantarum Ln4 from kimchi: Evaluation of β-galactosidase and antioxidant activities

This study was conducted to evaluate the probiotic properties, including β-galactosidase and antioxidant activities, of lactic acid bacteria isolated from kimchi. Two isolates with a probiotic potential were isolated and identified by 16S rRNA sequence analysis. For comparison, a commercial probiotic strain, Lactobacillus rhamnosus KCTC 12202BP, was used. The isolates, Lactobacillus plantarum Ln4 and G72, and L. rhamnosus KCTC 12202BP, were able to survive under artificial gastric conditions (pH 2.5 in the presence of 0.3% pepsin and 0.3% oxgall). The safety of the LAB strains was tested in terms of antibiotic resistance and production of harmful enzymes. Antibiotic resistance was assessed according to Clinical and Laboratory Standards Institute guidelines. Assessment with the API ZYM kit showed that none of the strains produced harmful enzymes, such as β-glucuronidase. Among the tested strains, L. plantarum Ln4 showed the strongest adhesion to HT-29 cells and the highest β-galactosidase activity (3320.99 Miller Units). L. plantarum Ln4 was found to have higher 1-diphenyl-2-picrylhydrazyl radical-scavenging (40.97%) and β-carotene oxidation-inhibitory activities (38.42%) than did L. rhamnosus KCTC 12202BP. These results suggest that L. plantarum Ln4 isolated from kimchi may have a probiotic potential and could be used in functional foods.

The hydrolytic enzymes produced by fungi strains isolated from the sand and soil of recreational areas

The pathogenicity of fungi depends on, inter alia, the secretion of hydrolytic enzymes. The aim of this study was to determine the enzymatic activity of yeasts and yeast-like fungi isolated from children’s recreation areas, and compare the results with literature data of strains obtained from patients with mycoses. The enzymatic activity of 96 strains was assessed using an API ZYM kit (bioMerieux, France) and their biotypes were established. The fungal species were found to produce from 16 to 19 hydrolases: the most active were: leucine arylamidase (e5), acid phosphatase (e10), alkaline phosphatase (e1), naphthol-AS-BI-phosphohydrolase (e11), esterase – C4 (e2), β-galac - tosidase (e13) and β-glucosidase (e16). In addition, 13 biotypes characteristic of particular species of fungi were defined. Most strains could be categorized as biotypes C2 – 39.5% and A – 26%. The examined fungal strains isolated from recreational areas have selected biochemical characteristics i.e. production of hydrolases, which demonstrate their pathogenicity. They produce a number of enzymes which are also present in strains isolated from patients with mycoses, including: leucine arylamidase (e5), acid phosphatase (e10), naphthol-AS-BI-phosphohydrolase (e11) and alkaline phosphatase (e1). The biotypes identified in the course of this study (A, B3, B4, C1, C6 and D3) have been also reported in cases of fungal infection. Therefore, the fungi present in the sand and soil of recreational have pathogenic properties and are possible factors of fungal infection among children.

Vibrio algivorus sp. nov., an alginate- and agarose-assimilating bacterium isolated from the gut flora of a turban shell marine snail.

An agarose- and alginate-assimilating, Gram-reaction-negative, non-motile, rod-shaped bacterium, designated strain SA2T, was isolated from the gut of a turban shell sea snail (Turbo cornutus) collected near Noto Peninsula, Ishikawa Prefecture, Japan. The 16S rRNA gene sequence of strain SA2T was 99.59 % identical to that of Vibrio rumoiensis DSM 19141T and 98.19 % identical to that of Vibrio litoralis DSM 17657T. This suggested that strain SA2T could be a subspecies of V. rumoiensis or V. litoralis. However, DNA-DNA hybridization results showed only 37.5 % relatedness to DSM 19141T and 44.7 % relatedness to DSM 17657T, which was far lower than the 70 % widely accepted to define common species. Strain SA2T could assimilate agarose as a sole carbon source, whereas strains DSM 19141T and DSM 17657T could not assimilate it at all. Furthermore, results using API 20NE and API ZYM kits indicated that their enzymic and physiological phenotypes were also different. These results suggested that strain SA2T represented a novel species within the genus Vibrio. The major isoprenoid quinone in SA2T was Q-8, and its major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The major fatty acids were summed feature 3, (comprising C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0, and summed feature 8 (comprising C18 : 1ω6c and/or C18 : 1ω7c). The DNA G+C content of SA2T was 40.7 mol%. The name proposed for this novel species of the genus Vibrio is Vibrio algivorus sp. nov., with the type strain designated SA2T (=DSM 29824T=NBRC 111146T).

Identification of β-Glucosidase Activity of E nterococcus Faecalis CRNB-A3 in Airag and Its Potential to Convert Ginsenoside Rb1 from Panax Ginseng

The objectives of this study were to isolate the lactic acid bacteria (LAB) exhibiting β-glucosidase activity from Airag, and investigate the hydrolytic activity of the enzyme on saponin (Korean ginsenoside). Of the 33 types of LAB with positive reactions (β-glucosidase) in the Esculin Iron Agar test, one LAB (CRNB-A3) was found to have high hydrolytic activity for ginsenoside Rb1. 16S rDNA analysis revealed that CRNB-A3 was Enterococcus faecalis (99.9% homology). The optimum temperature and pH for growth of CRNB-A3 in MRS broth were 35C and 8.0, respectively. Crude enzyme from E. faecalis CRNB-A3 showed ability to convert ginsenoside Rb1 into minor ginsenosides Rg3 and Rg5. The use of an API ZYM kit showed that E. faecalis CRNB-A3 had higher activities of leucine arylamidase, esterase and β-glucosidase than any other enzyme activities. Additionally, E. faecalis CRNB-A3 was identified as being hetero-fermentative. Practical Applications The fermentation of Panax ginseng yields many compounds from ginsenoside that have varying biological functions. These compounds are widely consumed in Korea and other Asian nations in the form of extracts, alcohols, candy, fermented liquids and pharmacological products. This study revealed that an Airag (Mongolian KOUMISS) LAB strain possessed a strong ability to convert ginsenoside Rb1 to Rg3 and Rg5, which could be used in food and cosmetic industries for making yogurts, beverage products, cosmetics and other products for ginsenoside supplementations.

Sporothrix schenckii COMPLEX:SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES.

SUMMARY Sporothrix schenckiiwas reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans (n = 1) , S. brasiliensis (n = 6) , S. globosa (n = 1), S. mexicana(n = 1) and S. schenckii(n = 36) to terbinafine (TRB) alone and in combination with itraconazole (ITZ), ketoconazole (KTZ), and voriconazole (VRZ) by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5%) or indifferent (70%, 50% and 52.5%) for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA) activity was observed only for S. albicans and S. mexicana. The species S. globosaand S. mexicanawere the only species without β-glucosidase (GS) activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrixin further studies.

Preliminary Characterization of Digestive Enzymes in Freshwater Mussels

ABSTRACT Resource managers lack an effective chemical tool to control the invasive zebra mussel Dreissena polymorpha. Zebra mussels clog water intakes for hydroelectric companies, harm unionid mussel species, and are believed to be a reservoir of avian botulism. Little is known about the digestive physiology of zebra mussels and unionid mussels. The enzymatic profile of the digestive glands of zebra mussels and native threeridge (Amblema plicata) and plain pocketbook mussels (Lampsilis cardium) are characterized using a commercial enzyme kit, api ZYM, and validated the kit with reagent-grade enzymes. A linear correlation was shown for only one of nineteen enzymes, tested between the api ZYM kit and a specific enzyme kit. Thus, the api ZYM kit should only be used to make general comparisons of enzyme presence and to observe trends in enzyme activities. Enzymatic trends were seen in the unionid mussel species, but not in zebra mussels sampled 32 days apart from the same location.Enzymatic classes, based on ...

Standardization and establishment of an in vitro culture of Blomia tropicalis toward technological development purposes

Standardization and establishment of an in vitro culture of Blomia tropicalis toward technological development purposes