Journal of BioScience and Biotechnology (JBB)

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https://doi.uni-plovdiv.bg/handle/store/2

p-ISSN: 1314-6238 / e-ISSN: 1314-6246

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3D structure prediction of lignolytic enzymes lignin peroxidase and manganese peroxidase based on homology modelling
(Plovdiv University Press “Paisii Hilendarski”, 2015-11-27) Kale, Swapnil K.; Deshmukh, Amit G.
Lignolytic enzymes have great biotechnological value in biopulping, biobleaching, and bioremediation. Manganese peroxidase (EC 1:11:1:13) and lignin peroxidase (EC 1:11:1:14) are extracellular and hem-containing peroxidases that catalyze H2O2-dependent oxidation of lignin. Because of their ability to catalyse oxidation of a wide range of organic compounds and even some inorganic compounds, they got tremendous industrial importance. In this study, 3D structure of lignin and manganese peroxidase has been predicted on the basis of homology modeling using Swiss PDB workspace. The physicochemical properties like molecular weight, isoelectric point, Grand average of hydropathy, instability and aliphatic index of the target enzymes were performed using Protparam. The predicted secondary structure of MnP has 18 helices and 6 strands, while LiP has 20 helices and 4 strands. Generated 3D structure was visualized in Pymol. The generated model for MnP and LiP has Z-score Qmean of 0.01 and -0.71, respectively. The predicted models were validated through Ramachandran Plot, which indicated that 96.1 and 95.5% of the residues are in most favored regions for MnP and LiP respectively. The quality of predicted models were assessed and confirmed by VERIFY 3D, PROCHECK and ERRAT. The modeled structure of MnP and LiP were submitted to the Protein Model Database.
A contribution to the knowledge of the trophic spectrum of three lacertid lizards from Bulgaria
(Plovdiv University Press “Paisii Hilendarski”, 2013-04-04) Mollov, Ivelin; Petrova, Slaveya
A study on the trophic spectrum of three species of lacertid lizards (Lacerta agilis, Lacerta trilineata and Podarcis muralis) was carried out, based on 20 specimens collected in the period 1967-1973 in various localities in Bulgaria. The analyzed data showed that the insects (Insecta) are the most numerous and the most frequently met among the alimentary components of the total amount of food of the studied stomachs (except for Lacerta agilis, where spiders are slightly predominating). The non-insect components consisted spiders and isopods. The largest niche breadth was recorded in Lacerta trilineata (8.25), followed by Podarcis muralis (5.20) and Lacerta agilis (3.44). The niche overlap between the three species (pair-wise comparison) showed medium values and in our opinion there should not be any serious competition for food resources at the places with sympatric distribution.
A novel neutral protease from thermophilic Bacillus strain HUTBS62
(Plovdiv University Press “Paisii Hilendarski”, 2012-10-15) Aqel, Hazem; Al-Quadan, Farouk; Yousef, Tahani K.
A novel neutral highly thermostable protease was detected in the culture medium of thermophilic Bacillus strain HUTBS62 isolated from hot-spring located near to the Dead Sea, Jordan. The enzyme was purified by precipitation with 55-60% ammonium sulfate, gel filtration on Sephadex G-100 and DEAE ion exchange chromatography. The enzyme was purified 53-fold with 2% yield. The optimum pH and temperature for catalytic activity of protease was pH 6.8 and 80ºC, respectively, and 31% activity of protease remained even after heat treatment at 100ºC for 60 min. The relative activity of the enzyme was highly stable (90%) at 50ºC for 2 h. The half-life of the enzyme at 90ºC, 80ºC and 70ºC was estimated to be 3, 4 and 6 h, respectively. The activation energy of denaturation of purified enzyme was 21.7 kJmol-1. Iron, sodium, calcium, and manganese increased protease activity. On the other hand, magnesium, cobalt and zinc variably decreased the residual activity. But cadmium and copper drastically inhibited the enzyme activity. The enzymatic activity was highly stable in the presence of 1 and 2 mM EDTA at pH 6.8 and 80ºC. The neutral protease therefore could be defined as a highly thermostable with new properties make the present enzyme applicable for many biotechnological purposes.
A novel polymerase chain reaction (PCR) based assay for authentication of cell lines or tissues from human, pig and chicken origin
(Plovdiv University Press "Paisii Hilendarski", 2012-05-11) Gorenjak, Mario; Trapecar, Martin; Gradisnik, Lidija; Skok, Pavel; Cencic, Avrelija
A polymerase chain reaction based assay was developed for authentication of cell lines or tissues from human, pig and chicken origin. Specificity was achieved by species specific primer design targeting the mitochondrial D-loop sequence. Amplicon sizes were 114 bp, 169 bp and 645-648 bp for chicken, human and pig derived cell lines, respectively. Primers were tested for species specificity and non-specificity between haplogroups of the same organisms using BLAST tool and subsequently for cross amplification DNA extracted from human, chicken and pig venous blood as a positive control. Primers were also amplifying specific products in DNA extracted from individual cell line in both functional cell models and intentionally mixed cell lines consisting functional cell models. The PCR assay developed in this study represents a low-cost species specific end-point PCR based assay of the mitochondrial D-loop for the authentication of the cell line origin.
A preliminary study of the effect of phytoadditive carvacrol on the trace elements (Cu, Mn and Zn) content in fish tissues
(Plovdiv University Press “Paisii Hilendarski”, 2014-01-08) Yılmaz, Ebru; Yılmaz, Sevdan; Ergün, Sebahattin; Kaya, Hasan; Kızılkaya, Bayram; Soytaş, Nergiz
Phytoadditives have gained increasing interest as feed additives for fish. The aim of the present study was to determine whether selected dietary phytoadditive can influence the bioavailability of several trace elements (Cu, Mn and Zn), which play an important role in the physiological processes. The experiments were carried out at a commercial trout farm. A total of 420 juvenile rainbow trout (mean weight ± SD = 10.79±0.57), Oncorhynchus mykiss, were randomly allocated into four different treatments with three replicates each. Fish were kept in raceways (3X0.8X0.4 m) at 10±1°C with a natural photoperiod. Proper amount of carvacrol was sprayed on 1 kg of commercial trout diet to prepare four diets with 0 (Control, C0), 1 (C1), 3 (C3) and 5 (C5) carvacrol g/kg diet. Fish were fed to apparent satiation three times per day. The feeding trial lasted four weeks. Then, in different type of fish tissues (muscle, liver and pyloric caeca) from fish fed with diets enriched in carvacrol, beneficial elements (Cu, Mn and Zn) were analysed by atomic adsorption spectrophotometer. Results showed that the levels of Cu, Zn and Mn were especially significantly increase by C1 diet in all tissues (muscle, liver and pyloric caeca) except muscle and pyloric caeca Zn. The results of this experiment indicate that the carvacrol had the ability to potentiate the trace element retention. Although bioaccumulations of Cu, Zn and Mn in the muscle, liver and pyloric caeca are well demonstrated, the exact mechanisms of phytoadditives are still only partially understood. More investigations are required to detail the mechanisms involved in phytoadditives this enhancement.
Aberrant promoter methylation in p53 and ATM genes was not associated with sporadic breast carcinogenesis in Bulgarian patients
(Plovdiv University Press “Paisii Hilendarski”, 2014-04-02) Krasteva, Maria E.; Antov, Georgi G.; Gospodinova, Zlatina I.; Angelova, Svetla G.; Nacheva, Maria B.; Georgieva, Elena I.; Gavrilov, Ivan G.
Epigenetic silencing of gene expression has become an intensively studied topic regarding breast cancer during the last years. Previous investigations have shown that hypermethylation in gene promoters is an alternative to mutations cancer-related mechanism for inactivation of tumor suppressor gene function. The present study was designed for evaluation of promoter methylation in p53 and ATM tumor suppressor genes in Bulgarian patients with sporadic breast cancer. Sodium bisulfite conversion and methylation-specific PCR were performed on tumor DNA isolated from 55 patients with sporadic breast cancer. The data showed normal profile of methylation in the promoter region of p53 and ATM genes in all studied patients. Cases with hypermethylation were not observed. Our results did not support the involvement of p53 and ATM promoter hypermethylation in the neoplastic pathways of sporadic breast cancer. The lack of promoter hypermethylation in p53 and ATM is suggestive of a greater share of genetic aberrations in loss of tumor suppressor function of these genes and presumes the involvement of other epigenetic cancer mechanisms. To our knowledge this study provides the first data on promoter hypermethylation status of p53 and ATM genes in Bulgarian patients.
Aberrant signature patterns of ATM, γ-H2AX and p53 proteins in the patients exposed to methyl isocyanate diagnosed with gallbladder cancer
(Plovdiv University Press “Paisii Hilendarski”, 2014-04-29) Jatawa, Suresh Kumar; Tiwari, Archana
Cancer of gallbladder is a hidden phenomenon and highly malignant with underprivileged diagnosis and poor survival. Study of cancer patterns amongst victims of Bhopal gas tragedy exposed to methyl isocyanate revealed higher incidence of gallbladder cancer that necessitated a more objective elucidation of the disease at its molecular level. Tissues of 92 cases of gallbladder cancer patients were taken in the study (31 men and 61 women, age range 16–85 years, mean age 45.8±1.50 years). Mutations of ATM, γ-H2AX and p53 were predominantly seen in the methyl isocyanate exposed cohort diagnosed with adenocarcinoma, with 61.4% (43/70), 54.3% (38/70) and 73% (51/70) respectively, involving infiltration into the papillary and mucinous region/cell types of the gallbladder. Out of these, the expression frequency of all the above three genes was higher in moderately differentiated adenocarcinoma in comparison to poorly and well-differentiated ones. The results of the present study support the hypothesis that ATM and p53 mutations provide fundamental genetic signatures influencing tumor behavior across patient subsets and invasiveness of the disease, while γ-H2AX is apparently an ordinary pathway involved in the genesis of tumors.
Acetylcholinesterase inhibitory, antioxidant, and antimicrobial activities of Salvia tomentosa Mill. essential oil
(Plovdiv University Press “Paisii Hilendarski”, 2015-08-10) Marchev, Andrey; Ivanov, Ivan; Denev, Petko; Nikolova, Milena; Gochev, Velizar; Stoyanova, Albena; Pavlov, Atanas; Georgiev, Vasil
Chemical composition and bioactivity of essential oil from Salvia tomentosa Mill. natively grown in Bulgaria were investigated. GC-MS analysis identified 60 compounds which represented 98% of the oil constituents. The prevalent constituents were monoterpenes with eight dominant compounds being identified: borneol (10.3%), β-pinene (9%), camphor (7.9%), α-pinene (6%), camphene (4%), 1.8-cineole (3.8%), α-limonene (3.5%) and β-caryophyllene (3%). The essential oil showed considerable acetylcholinesterase inhibitory activity (IC50=0.28±0.06 μg/mL), comparable with that of galanthamine. Study of antioxidant activity strongly suggested that the hydrogen atom transfer reaction was preferable over the electron transfer (ORAC=175.0±0.40 μM Trolox equivalents/g oil and FRAP=1.45±0.21 mM Trolox equivalents/g oil). The essential oil showed moderate antifungal and antibacterial activities against Candida albicans and Gram-positive bacteria, whereas it was almost inactive against the investigated Gram-negative strains. The results suggested that the essential oil of Bulgarian S. tomentosa could be considered as a prospective active ingredient for prevention of oxidative stress-related and neurodegenerative disorders in aromatherapy. Because of the high antioxidant capacity, the oil could be considered as natural supplement or antioxidant in cosmetics and food products.
Adenovirus Serotype 5 Vectors with Tyr3-Octreotate Modified as a Virulytic Oncotherapy Agent in AGS Cells
(Plovdiv University Press “Paisii Hilendarski”, 2020-09-17) Salkhori, Najmeh Yarkeh; Farivar, Taghi Naserpour; Noroozi, Jamileh; Najafipour, Reza; Pakzad, Parviz
Background: Oncolytic viral therapy is known as a new promising strategy to treat cancer. Oncolytic viruses (OVs) can replicate in cancer cells, and beside this primary effect, OVs can also stimulate the immune system. Moreover, Adenovirus serotype 5 (Ad5) is widely used as an oncolytic agent for cancer therapy. The present study aimed to make a change in the adenovirus fiber area. Methods: The tyr3-octreotate sequence was inserted into the HI-loop in the adenovirus fiber knob. In addition, recombinant virus was transferred to the HEK-293 packaging cells using the calcium phosphate method; therefore, the new virus was prepared. Accordingly, virus titer was calculated using the TCID50 method. Afterward, recombinant adenovirus and wild-type 5 strain were transferred to perform against human adenocarcinoma gastric cell line (AGS). Subsequently, they were evaluated for cytopathic effects, and the manipulated virus was then confirmed Using PCR and sequencing. Results & Conclusions: In this regard, the obtained results showed that the recombinant adenovirus has a greater ability in infecting AGS cells compared to the wild-type adenovirus. Our data suggest that, modification of Ad5 with tyr3-octreotate expands its usage as an oncolytic agent against the AGS cells.
Agronomic performances and nutritional composition of three morphotypes of spider plant (Cleome gynandra L.) under different doses of compost
(Plovdiv University Press “Paisii Hilendarski”, 2019-07-15) Kiebre, Zakaria; Traore, Ernest Renan; Kiebre, Mariam; Bationo-Kando, Pauline; Kabore, Dramane; Sawadogo, Boureima; Sawadogo, Mahamadou
Spider plant is an important dietary supplement for the local population of Burkina Faso. The present study aims to evaluate the agronomic and biochemical response of three morphotypes to the variation of compost dose. The split-plot design with three repetitions was used for experiment. Three morphotypes, i.e slightly-violet, green and violet, were evaluated using four doses of compost. The results revealed that the agromorphological traits and biochemical composition vary considerably according to the compost dose. About 6t/ha was identified as the best for biomass production and nutritional profile of spider plant. In general, the agronomic response of morphotypes to the variation of compost dose is not significantly different, except biomass. However, under low fertility conditions, the green morphotype records the best performances whereas in high fertility conditions, the slightly-violet records the best performances. For the biochemical composition, the content of nutrients depends more of compost dose than morphotype.
Allelopathic tolerance in white lupine (Lupinus albus L.) accessions to Sorghum halepense extracts
(Plovdiv University Press “Paisii Hilendarski”, 2019-07-15) Georgieva, Natalia
Modern farming requires a better understanding of the response of species, and in the particular experiment, of accessions, to the influence of weeds in order to develop agricultural systems that are more dependent on ecological interactions and less dependent on the use of pesticides. The present lab study aimed to estimate the tolerance of white lupine accessions to Sorghum halepense extracts on the seed germination and initial growth of the crop. Studied factors were: white lupine accessions – ten levels (Lp01, Lp04, Lp06, Lp10, Lp21, Lp23, Lp25, Lp27, Lp28 Lp29), aqueous extracts – two levels (shoot and root biomass of S. halepense) and concentrations of the extracts – four levels (1.0%, 5.0%, 10.0% and distilled water as control). The results showed a different tolerance of the ten accessions to allelopathic action of the aqueous extracts. Increasing concentrations of the extracts inhibited seed germination (by 5.0 to 10% in the different accessions), elongation and accumulation of primary germ (2.4 to 71.2% and 3.0 to 56.2%, respectively. The GGEbiplot analysis, representing the summary effect of the action of weed extracts on the germination and growth parameters in different concentrations, determined Lp 01, Lp 04 and Lp 10 as tolerant. Sensitivity exhibited Lp 21, Lp 25 and Lp 23. The correlation analysis of data showed that accessions whose seeds had a higher 1000 seeds mass, higher seed vigor index and protein content were less affected by the inhibitory effect of S. halepense extracts, respectively, they exhibited a higher tolerance.
Allelopatic effects of some medicinal plant essential oils on plant seeds germination
(Plovdiv University Press “Paisii Hilendarski”, 2015-11-29) Shokouhian, Ali; Habibi, Hassan; Agahi, Kayvan
The effect of essential oils from some medicinal plants on seed germination was studied with the aim of assessing their potential use as bioherbicides. The experiment was conducted as factorial based on completely randomized design (CRD) with three replications. Seeds of 3 summer crops including lettuce (Lactuca sativa), pepper (Piper longum) and tomato (Solanum lycopersicum) were exposed to essential oils of rosemary (Rosmarinus officinalis), thyme (Thymus vulgaris) and anise (Pimpinella anisum) at 3 different concentrations (25 and 50% diluted and undiluted). Treated seeds were grown in a growth chamber at 25°C for 5 days. The number of germinated seeds in each Petri dish was daily counted. After five days seed germination percentage (Ge) was calculated. Biplot analysis was performed using genotype plus genotype environment interaction (GGE) method. Results showed that the allelopathic effect on Ge was varied among studied plants, which was mainly due to i) differences in the composition of the studied essential oils and ii) different allelopathic effects of the studied essential oils on Ge. Accordingly, compared to the individual use, combining several essential oils would have a greater inhibitory effect on Ge of weeds.
Allozyme genetic polymorphism in Bulgarian honey bee (Apis mellifera L.) populations from the south-eastern part of the Rhodopes
(Plovdiv University Press "Paisii Hilendarski", 2012-05-13) Ivanova, Evgeniya; Staykova, Teodora; Stoyanov, Ivan; Petrov, Plamen
Allozyme genetic polymorphism in Bulgarian honey bee populations from four different locations in the south-eastern part of the Rhodopes Mountain was studied on six enzymic systems (MDH, ME, EST, ALP, PGM and HK) corresponding to six genetic loci. Allozyme analysis revealed that all studied loci were polymorphic in almost all investigated populations. The observed heterozygosity was found to range from 0.110 to 0.208 and Nei’s genetic distance – between 0.016 and 0.061 among the studied populations. These honey bee populations were clustered in two groups in the UPGMA dendrogram. The Tihomir population was in a separate clade while other three populations (Kardzhali, Krumovgrad and Dolni Yurutci) were grouped together.
Alternative substrates for higher mushrooms mycelia cultivation
(Plovdiv University Press “Paisii Hilendarski”, 2015-11-18) Krupodorova, Tetiana A.; Barshteyn, Victor Yu.
Cultivation of 29 species of higher mushroom mycelia on alternative substrates – wastes of Ukrainian oil-fat industry, has been investigated. The amount of mushroom mycelia obtaining on 12 investigated substrates varied significantly, from 1.0 g/L to 22.9 g/L on the 14th day of cultivation. The superficial cultivation adopted in this study allows for easy to choose appropriate medium (substrate) for mycelia production. Alternative substrates (compared to glucose-peptone-yeast medium) were selected for all studied species, from soybean cake – most suitable for the mycelial growth of 24 species, to walnut cake − suitable only for 2 species. The utilization of substrates has been evaluated by biological efficiency. The best index of biological efficiency varied from 19.0% to 41.6% depending on the mushroom species. It was established high biological efficiency of mycelia cultivation on substrates: wheat seed cake – Pleurotus djamor, Lyophyllum shimeji, Crinipellis schevczenkovi, Phellinus igniarius, Spongipellis litschaueri; oat seed cake – Ganoderma applanatum and G. lucidum; soybean cake – Hohenbuehelia myxotricha, Trametes versicolor, Morchella esculenta, Cordyceps sinensis, C. militaris, and Agrocybe aegerita; rape seed cake – Auriporia aurea; camelina seed cake – Fomes fomentarius. The cultivation of these species are perspective as a biotechnological process of agricultural wastes converted into mycelia, which could be used in different forms of products with therapeutic action: powder or tablets nutraceuticals or ingredients for functional foods.
An in silico analysis of the glutamate dehydrogenases of Teladorsagia circumcincta and Haemonchus contortus
(Plovdiv University Press “Paisii Hilendarski”, 2014-01-09) Brown, Simon; Muhamad, Noorzaid; Walker, Lisa R.; Pedley, Kevin C.; Simcock, David C.
Nematode glutamate dehydrogenase (GDH) amino acid sequences are very highly conserved (68-99% identity) and are also very similar to those of the bovine and human enzymes (54-60% identity). The residues involved in binding nucleotides or substrates are completely conserved and tend to be located in highly conserved regions of the sequence. Based on the strong homology between the bovine, Teladorsagia circumcincta and Haemonchus contortus GDH sequences, models of the structure of the T. circumcincta and H. contortus monomers were constructed. The structure of the T. circumcincta monomer obtained using SWISS-MODEL was very similar to that of the bovine enzyme monomer and the backbone of the polypetide deviated very little from that of the bovine enzyme monomer. Despite the sequence differences between the bovine and T. circumcincta enzymes, the relative positions and orientations of the residues involved in ligand binding were very similar. The reported Km for NADP+ of T. circumcincta is about 35 and times that of the bovine enzyme, whereas the Kms of the two enzymes for glutamate, -ketoglutarate and NAD(P)H are much more similar. The residue corresponding to S267 of the bovine enzyme is involved in binding the 2′-phosphate of NADP+ and is replaced in the T. circumcincta and H. contortus sequences by a tryptophan. The partial occlusion of the NAD(P)-binding site by the tryptophan sidechain and the loss of at least one potential H-bond provided by the serine may explain the lower affinity of the T. circumcincta for NADP+.
Analysis of healthy cohorts for single nucleotide polymorphisms in C1q gene cluster
(Plovdiv University Press “Paisii Hilendarski”, 2015-11-26) Radanova, Maria A.; Ivanova, Petya P.; Ivanova, Diana G.
C1q is the first component of the classical pathway of complement activation. The coding region for C1q is localized on chromosome 1p34.1–36.3. Mutations or single nucleotide polymorphisms (SNPs) in C1q gene cluster can cause developing of Systemic lupus erythematosus (SLE) because of C1q deficiency or other unknown reason. We selected five SNPs located in 7.121 kbp region on chromosome 1, which were previously associated with SLE and/or low C1q level, but not causing C1q deficiency and analyzed them in terms of allele frequencies and genotype distribution in comparison with Hispanic, Asian, African and other Caucasian cohorts. These SNPs were: rs587585, rs292001, rs172378, rs294179 and rs631090. One hundred eighty five healthy Bulgarian volunteers were genotyped for the selected five C1q SNPs by quantative real-time PCR methods. International HapMap Project has been used for information about genotype distribution and allele frequencies of the five SNPs in, Hispanics, Asians, Africans and others Caucasian cohorts. Bulgarian healthy volunteers and another pooled Caucasian cohort had similar frequencies of genotypes and alleles of rs587585, rs292001, rs294179 and rs631090 SNPs. Nevertheless, genotype AA of rs172378 was significantly overrepresented in Bulgarians when compared to other healthy Caucasians from USA and UK (60% vs 31%). Genotype distribution of rs172378 in Bulgarians was similar to Greek-Cyriot Caucasians. For all Caucasians the major allele of rs172378 was A. This is the first study analyzing the allele frequencies and genotype distribution of C1q gene cluster SNPs in Bulgarian healthy population.
Analyzing inhibition of BCL11A gene expression in K562 cells by RNAi
(Plovdiv University Press “Paisii Hilendarski”, 2013-07-23) Vikas, Urkude; Amit, Mishra; Mahavir, Yadav; Archana, Tiwari
RNA interference (RNAi), an effective approach to sequence-specific gene knockdown is widely used for the investigation of regulation of gene expression in various cells. BCL11A (B cell lymphoma 11A) plays a vital role in the evolutionarily different globin gene switches of mammals. In the current study, siRNA complementary to BCL11A was used to inhibit the BCL11A gene expression in erythroleukemic K562 cells and the expression was evaluated through real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis. On day 7 of cell culture, 1x106 K562 cells were transfected with lipofectamine containing BCL11A specific siRNA. GAPDH (Glyceraldehyde-3-phosphate dehydrogenase) was used as the reference gene to confirm the relative expression level of BCL11A gene mRNA and BCL11A protein. After 48 h of transfection, BCL11A specific siRNA produced significantly reduction of BCL11A mRNA level in a dose-dependent manner. It also affects the level of BCL11A protein. BCL11A siRNAs were equally effective at reducing the expression level of BCL11A mRNA and protein.
Anti-enterotoxic activity of Areca, Origanum majorana, and Long pepper on Staphylococcal enterotoxins: A mixture study
(Plovdiv University Press “Paisii Hilendarski”, 2021-05-17) Naddafi, Seyyed Javad; Sani, Ali Mohamadi; Salehi, Esmaeil Ataye; Karazhyan, Reza
The present paper studies antibacterial activity (AA) and anti-enterotoxigenic activity (AEA) of three Iranian medicinal plant extracts, Origanum majorana, Areca, and Long pepper. In addition, the anti-enterotoxigenic interactive effects of these extracts as herbal extract blend (HEB) were studied. Kirby-Bauer, agar dilution, and Real-time PCR methods were used to study the AA and AEA of the extracts. The statistical method of mixture design was used to optimize and find out the best HEB with the highest AEA on A and B enterotoxins of S. aureus. In individual AA study of extracts, O. majorana extract had the highest AA. Among the extracts evaluated in this study, the extract of O. majorana had much AA on S. aureus and its enterotoxins production. As an interesting result, there is an inhibitory synergistic effect between the extracts studied in this paper on gene expression of sea and seb. The maximum AEA was observed by treat with HEB including 47% O. majorana, 26% Areca, and 27% long pepper.
Antifungal susceptibility and virulence factors of Candida spp. isolated from the genital tract of outpatients
(Plovdiv University Press “Paisii Hilendarski”, 2020-09-17) Tsankova, Marinela Krasimirova; Marhova, Mariana; Kostadinova, Sonya; Iliev, Ivan
The vaginal yeast infections are one of the most widespread infection diseases among women. The present study is focused on the taxonomic composition, antifungal resistance and some virulence factors of Candida strains isolated from samples of outpatients. During one year period from April 2016 to March 2017 the 97 Candida spp. strains were collected from vaginal, cervical and urethral secrets of outpatients at IMDL “Chronolab” Plovdiv. The majority of isolates were identified as C. albicans (84%), followed by Candida glabrata (7%), Candida krusei (4%), Candida parapsilosis (3%) and Candida tropicalis (2%) and the most affected age group is women between 21 and 40 years old. Antifungal resistance was low and mainly associated with C. glabrata, with total susceptibility to the tested antifungal drugs over 95%. Analysis of the hydrolytic enzyme activities and the biofilm formation abilities showed that only 8% of the strains produced gelatinase and phospholipase, 6% produced caseinase and 5% esterase. Seven of the tested Candida strains (7.2%) formed stable biofilm after 24 h cultivation in Sabouraud dextrose broth supplemented with 6% glucose. This study revealed no significant correlation between the antifungal susceptibility and the studied virulence factors of Candida spp. isolates from the genital tract of outpatients.
Antimicrobial activity of crude extract of endophytic fungi isolated from leaves of Kigelia africana and Phyllanthus niruri collected from Dar es Salaam Tanzania
(Plovdiv University Press “Paisii Hilendarski”, 2022-06-07) Privatus, Prudence; Maethya, Jane D.; Mpenda, Fulgence N.
One of the main challenges that hinder achievement of the third millennium sustainable development goal is emergence of infectious agents that are resistant to existing antimicrobials. These challenges entails search for novel bioactive compounds like exploring untapped potential of medicinal plants and their associated endophytes. The present study was aimed to investigate the antimicrobial activities of crude extracts of endophytic fungi isolated from medicinal plants Kigelia africana and Phyllanthus niruri. Pure isolates of endophytic fungi were subjected to initial screening, and isolates that exhibited inhibition were genotyped by Sanger sequencing for genus and species confirmation. Then, antimicrobial activity of crude extracts of selected isolates: Nigrospora sphaerica, Meyerozyma guilliermondii, Alternaria alternata and Phyllosticta capitalensis was evaluated by disc diffusion method against E. coli (Gram-negative), S. typhi (Gram-negative), and S. aureus (Gram-positive). Findings indicated high variability (8.5 -23.1 mm) of crude extract concentrations of isolates, and the highest zone of inhibition was found in ethyl acetate crude extract of M. guilliermondii against S. aureus. Furthermore, the lowest MIC (9.9 >MIC>5.0) was found in n-hexane crude extract of P.capitalensis against S. typhi. However, all crude extracts did not show any activity against E. coli. Results of present study corroborate on the influence of extracting solvent on the effectiveness of crude extract of isolates against pathogen microorganisms. Interestingly, findings demonstrated the potential of endophytes from medicinal plants for medical applications, and therefore further investigation may lead to discovery of novel bioactive compound potent to resistant infectious agents.

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