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Aim and Background. Spermatogenesis is a process In which spermatozoids Is produced Whose defect in each stepany defect in each step can Can result result in infertility. F. parviflora contains isoquinoline and protopine alkaloids and h as antioxidant activity. F. parviflora has been used in folk medicine for its pharmaceutical properties. One of the most important effects of this plant is increasing sexuality. The aim of this study is to investigate the effect of the F. parviflora alcoholic extract in spermatogenesis process.

Materials and Methods. Wistar male rats (230 ± 5) are divided into 2 groups: control and experimental. The control group received distilled water whereas the experimental group received 250 mg/kg w.b. F. parviflora alcoholic extract through oral gavage for 5 days. After 15 days rats were anesthesized and sacrificed and the Testis were removed. The volume and weight of the testis were measured and the tissues were fixed. The preparation of tissue sectioning was accomplished by H&E staining. Germinal cell lines cells were counted with light microscope. Statistical analysis was performed with One Way Anova using SPSS for Windows.P ≤0.05 was considered statistically significant.

Results. The analysis of the results indicated there were no significant difference in weight and volume of testicles but significant increase in the number of spermatogonia ,spermatocytes ,spermatozoid and Leydig cells were observed in experimental group compared to the control group (P<0.001).

Conclusions.The results indicated positive effect of F. parviflora alcoholic extract on male reproductive system Since the number of number of sexual cells increased significantly.

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Aim and background: Epidemiological and animal experimental studies indicated that flavonoid rich diets could affected positively on decrease of the prevalence of neuronal degenerations e.g Alzheimer and Parkinsonism diseases. In basis of the positive function of crataegus extract on decrease of oxidative factors and other helpful chararacteristics of this extract, the present research examined crataegus extract effect on passive avoidance learning of male wistar rat.

Materials and Methods: 24 rats with 250-300 gram weight have been divided to three main groups: 1-control (intact) 2- sham (solvent receivers) 3-Crataegus extract. This extract has been administered daily (100mg/kg) for two weeks by gavages' method. Passive avoidance learning test were achieved by shuttle box system. One day after acquisition retrieval test has been done. For this, animal was putted to light compartment and after 30 seconds guillotine door was opened and the time that was consumed for entering to dark component was recorded. Data were analyzed by SPSS software with one way ANOVA and Tuckey test.

Results: were indicated no difference between intact and sham groups for time of entering to dark component but there was significant increase between extract and intact groups (P<0.001) and decrease between them for entering to dark component (P<0.001)

Conclusion: Results of this study showed that treatment by Crataegus extract that is flavonoid rich, has been resulted to recovery of learning and memory.

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Aim and Background. .Ageing could been resulted to increase of oxidative stress that could lead to damage of brain processes including cognitive functions. Since Hypericum extract have decreasing effect on the stress, it’s effect on passive avoidance learning of restrained male wistar rats were examined. 

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Aim and Background: Nocardia spp are Gram-positive, partially acid-fast causing various infections. Due to the complex structure of the cell wall of the microorganism that is similar to mycobacteria, DNA extraction from this bacterium is different from other bacteria. The boiling method with STET buffer solution was used for DNA extraction of Nocardia.
Materials and Methods: Nocardia colonies were suspended in 200 µl STET buffer and was boiled for 30 minutes. Suspension was centrifuged and transferred to another micro tube and Ethanol %95 was added and saved at -20 °C for 30 minutes. After this stage, sample was centrifuged and the supernatant was discarded. In the first stage, distilled water was added and stored at -20 °C for molecular works. To confirm the presence and quality of the DNA extract, the electrophoresis on a %1 agarose gel was carried out and PCR reaction 16S rRNA gene was used.
Results: DNA was extracted on agarose gel and the purity and quality was appropriate. 16S rRNA gene PCR was then performed and observed to be 1500 bp.

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Aims and Background: RNA extraction with high quantity and quality is a fundamental requirement for molecular biology studies. Presence of carbohydrate, tannins, proteins and polyphenols compounds have created problem for extracted RNA from woody plant. Therefore, it is important to a suitable extraction method to produce a good quality RNA.
Materials and Methods: Methods for RNA extraction were compared to choose the best method of RNA extraction from pomegranate (Punica granatum L.) peel. These methods included 1-Zarei et al 2- IHTB 3-CTAB–LiCl modified method.
Results: Of the methods tested, Zarei et al method is the most appropriate method for plants with high phenolic compounds, especially pomegranate. Hence the need for the use of dangerous chemical material and extraction kits is not felt.
Conclusion: At the end of experiment with attention to results and comparison between methods, Zarei et al method was selected as the best method for RNA extraction from fruit peel with high quantity, quality and purity. Maximum amount of RNA with high quality that extracted from Zarei et al method was 642 ng per 100 mg peel tissue.

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Aims and Background: Diabetes mellitus is a chronic disease caused by lack of insulin secretion or inability of cells to use insulin. Various methods are used to treat the disease; however they are associated with many problems. Therefore, access to novel methods of treatment and prevention of the disease is of great importance. This study investigated the impacts of a native probiotic of Iran and cumin plant extract on reducing blood sugar levels in diabetic rats.

Materials and Methods: Thirty-five male Wistar rats aged 4 weeks, with same weighs of 110-130 g were selected. After 2 weeks of adaptation, they were made diabetic by streptozotocin and divided randomly into normal control, diabetic control, probiotic receiving diabetic, cumin receiving diabetic, and probiotic plus cumin receiving diabetic groups. The probiotic used was Bacillus subtilis JQ61819, purchased as lyophilized powder (1×10⁹ cfu/g) from Takgene Co., and cumin extracts were purchased from Barij Essence pharmaceutical Co. The rats were daily fed with the probiotic and cumin through gavage using a needle. After the treatment period, the rats were anesthetized and blood samples were taken from their hearts, and sugar and lipids were measured in serum using appropriate kits.

Results: Bacillus subtilis and cumin extract lowered blood sugar by 61% and cholesterol by 44% and increased triglycerides by 14% in diabetic Wistar rat models.

Conclusion: The use of indigenous probiotic Bacillus subtilis alone or in combination with cumin extract may be useful in controlling blood sugar in patients with diabetes.

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Aim and Background: One of the most common acquired infections is urinary tract infections (UTI). This problem is associated with the wild antibiotics treatment for UTI. In this study, the effect of zangaber extracts were compared with antibiotics for treatment of UTI . Materials and Methods: 100 samples were isolated from patients with UTI. Bacteria were identified with biochemical tests. Then was used antibiogram with different antibiotics and resistant bacteria were isolated. Antibacterial effect of different concentrations from zangaber extracts were tested on resistant bacteria. Results:From 100 isolates, 46 samples were E. coli, 10 were Proteus mirabilis, 9 were Pseudomonas aeruginosa, 5 were Staphylococcus aureus, and 30 samples were other bacteria. The lowest MIC for E. coli was found Nitrofurantoin and Nalidixica cid, Ceftriaxone and Cephazolin were for Proteus mirabilis, Pseudomonas aeruginos and Staphylococcus aureus. The highest MIC for zangaber was found by methanolic extract of zangaber. Conclusion: Results have shown most of bacteria have become resistant to antibiotics. As also, by increasing of antibiotic application for UTI treatment was produced resistance bacteria, therefore plant drugs with antibacterial effects such as zangaber is required. This plant can be inhibited of uropathogenic bacteria.

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Aim and Background: Among cancers, Lung cancer is considered to be the most important cause of death in worldwide and as the most modern cancer treatments are ineffective with side effects, it seems essential to find impressive alternatives treatment. Nettle plant with the scientific name Urtica dioica L. Of family Urticaceae, is a flowering and Perennial plant that has high nutritional and medicinal value. There fore, the cytotoxic effect of ethanolic extract of nettle leaf (Urtica dioica L.) on A549 cell lines was evaluated. Materials and methods: In this study, for the first time, the cytotoxic effect of ethanolic extract of nettle leaves on A549 cell lines was evaluated. The dioecious nettle leaves in April 2015 of sehezare Tonekabon were collected and studied; Then the antioxidant activity was evaluated by DPPH0 Assay. A549 cell line in DMEM with 20% fetal bovine serum was grown. Different concentrations of ethanolic extract of two legs nettle leaves (5, 2/5, 1/25 and 0/5 mg/ml) for 24, 48 and 72 hours were applied on cancer cells A549. Next the viability of cells using MTT assay was considered. Results: In this study, the percent of free radical scavenging DPPH0 equals to 67/79 percent and the amount of IC50 was calculated to be 4/30 mg/ml. The results of MTT assay showed that the ethanolic extract of nettle leaves has a cytotoxic effect on the A549 cell line which is dependent to their doses. Also IC50 of the extract concentration for A549 cells was obtained to be 5 mg/ml. MTT results showed no significant differenc in 48 and 72 hours. But the difference was significant at 24 hours. Conclusion: The ethanolic extract of nettle leaves which is dose-dependent could destroy the cancer cells and showed cytotoxic properties. Thus, this plant can be used as a medicinal plant against lung cancer in wider scope.

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Aim and Background:
Rose scientific name is Rosa damascene Mill. The aim of this study was to evaluate the quality and quantity of phenolic compounds in this plant that treated by both manure and chemical fertilizers.
Material and methods:
After appropriate treatments (manure and chemical fertilizers) at 2 habitats and 3 replication extraction conducted  by soaking in 70% ethanol. Then measurement of phenolic and flavonoids compounds has been done by spectrophotometry method.
Results:
The results of phytochemical tests confirmed the presence of tannin, anthocyanin and flavonoids and absence of alkaloids in all treatments. Chemical fertilizer increased the flavonoids compounds manure fertilizer increased phenolic compounds
Conclusion:
Results indicated that the efficiency of different treatments can effect of plant’s extract efficiency and phenolic compounds that So far for this plant species has not been reported in the scientific literature.

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Aim and Background: One of the most important researches is related to garlic and it has great anti-bacterial properties. The purpose of this research is the evaluation of garlic extract effect with various concentrations on Staphylococcus aureus, Streptococcus pneumonia and Shigella dysenteriae bacteria and also comparing the results in laboratory situation.
Material and Methods: In this study, garlic extract was prepared and to determine the Minimum Inhibitory Concentration (MIC) of the extract, the Standard Tube Test was used. As well as, to compare with antibiotics, the Disk Diffusion Method was used. The experiment was conducted in a completely randomized design with 3 repetitions and comparisons of the averages were performed using Tukey's method.
Results: The MIC of garlic extract based on Mg/dl on studied bacteria with extract of respectively: 15, 23 and 25mm with concentration of 1/2 Mg/dl; 12, 20 and 22mm with concentration of 1/4Mg/dl; 10, 16 and 18mm with concentration of 1/8 Mg/dl; 0, 13 and 15mm with the concentration of 1/16, 1/32 and 1/24 was zero. According to the results of this research in laboratory condition anti-bacterial properties of garlic has the inhibitory effect on studied bacteria.
Conclusion: The results indicate that the inhibitory effect of garlic extract on studied bacteria, in laboratory environment, is as good as antibiotics.
 

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Aim and Background:
The Antibiotic resistance provides area to replace herbal treatment methods that have fewer side effects   than common drugs. This study aimed to determine the antimicrobial effect of aquatic and ethanolic extracts of oleander (Nerium oleander) plant on the bacteria Salmonella Typhi and Listeria monocytogenes.
Material and methods:
In this experimental study, oleander plant leaves were gathered from Lahijan Plants Research Center located in Gilan province and after extracting, the Anti-bacterial effect of aquatic and ethanolic plant extracts was carefully evaluated against two strains of standard Salmonella Typhi PTCC 1609 and Listeria Monocytogenes PTCC 1295. And moreover, antimicrobial activity, minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) extracts, using serial dilution in broth and agar diffusion technique was determined.
Results:
In the method of diffusion in agar, all concentrations of oleander ethanol extract on Salmonella Typhi had deterrent effect. Yet, the deterrent effect of its ethanoic extract, compared to the aquatic extract is incomparably higher. The minimum inhibitory concentration of the ethanol extract 128 mg/ml and the minimum bactericidal concentration 256 mg/ml was subsequently determined. Aquatic and ethanol   extracts of this plant were not proved to be effective on the standard strain of Listeria Monocytogenes.
Conclusion:
It seems that the ethanolic and aqueous extracts of oleander plant has a substantial antimicrobial effect   on gram-negative bacterium Salmonella Typhi, under laboratory conditions. Therefore, they can be implemented more efficiently as pharmaceutical compounds or preservatives.
                                                                    

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Aim and Background:
Anaplastic thyroid cancer, including the most dangerous type of thyroid cancer.and as the most modern cancer treatments are ineffective with side effects, it seems essential to find impressive alternatives treatment. Lavender plant with the scientific name Lavandulla anguostifouliyaof familyLamiaceae, is a Perennial plant that has high nutritional and medicinal value. Therefore, the cytotoxic effect of ethanolic extract of Lavender plant on 8305C cell lines was evaluated.
 
Materials and methods:
In this study, for the first time, the cytotoxic effect of ethanolic extract of Aerial organsLavender plant on 8305c cell lines was evaluated. The Lavender plant in April 2016 of sehezare Tonekabon were collected andstudied; Then the antioxidant activity was evaluated by DPPH⁰ Assay. 8305C cell line was cultured in DMEM with 10% fetal bovine serum. Different concentrations of ethanolic extract of Lavender plant (5, 10, 20, 30, 40 and 50 mg/ml) for 24, 48 and 72 hours were applied on cancer cells 8305C. Then, the viability of cells using MTT assay was considered.
 
Results:
In this study, the free radical scavenging DPPH⁰ equals to 6/27mg/ml was calculated. The results of MTT assay showed that the ethanolic extract of Lavender plant has a cytotoxic effect on the 8305C cell line which is dependent to their doses. Also IC₅₀ of the extract concentration for 8305C cells was obtained to be 5 mg/ml in time 48 hours.
 
Conclusion:
The ethanolic extract of Lavender plant which is dose-dependent could destroy the cancer cells and showed cytotoxic properties. Thus, this plant can be used as a medicinal plant against anaplastic thyroid cancer in wider scope.

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Aim and Background:Narcissus family plants are important in addition to their ornamental value in terms of aromatic and medicinal compounds. The present study was conducted to investigate the quantitative and qualitative properties of phenolic compounds and antioxidant activity of four genotypes of Narcissus with the local name: Shahla, Meskin, Shasteper and Panjeh gorbeie in two phenological stages (beginning and end of harvest season).
Material and methods:For this purpose, after collecting plant materials in the natural habitats of Behbahan, drying and cold extraction were done. In this experimental study, the phytochemical study of the plant was first performed, then the total phenolic and flavonoid compounds were measured by spectrophotometric method. Finally, the antioxidant activity of the extract at different concentrations was determined using DPPH assay.
Results:The results showed that the extract yield in the sample of Maskin was more than the other samples at the beginning of harvest season. Also, compounds such as tannin and alkaloids were observed in some samples, that, varied in different these genotypes. The high percentage of DPPH inhibition is also confirmed the high antioxidant properties of these genotypes, although the three genotypes had the same degree of DPPH inhibition level, but the highest antioxidant activity is related to Meshkin with inhibitory percent 72.93 and the least anti-oxidant property related to Shahla with an inhibition rate of 91.895. According to the results, Maskin and Shahla genotypes showed the highest and least antioxidant properties, respectively.
Conclusion:The results of this study indicate that there is a significant difference in the composition and percentage of inhibition of DPPH free radicals in the extract of various nursery plants, which has not been reported for this plant in scientific sources.

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Aim and Background: Flax seed is a nutritive grain which can prevent cancers and cardiovascular diseases, due to compounds such as omega 3 fatty acid, dietary fiber, protein and lignan. The aim of this study was to investigate the effect of oil extraction method on extraction efficiency and the amount of phenolic and antioxidant substances.
Materials and Methods: In this research two kinds of yellow and brown flaxseed were used for extraction of oil by cold press and solvent method (petroleum ether and ethanol) and extraction efficiency and phenolic and antioxidant compounds were compared.
Results: The results showed that oil extraction was not possible with cold pressing method of yellow flax, and only meal was obtained. The yield of oil extraction for yellow and brown flax using ethanol were (6.6 ± 0.55 and 42.3 ± 1.15) and, for petroleum ether was (11.3 ± 0.98 and 63.03 ± 2.5) respectively. The evaluation of total phenolic compounds and the antioxidant effect of extracted solvents and cold press showed that there was a significant difference between the amount of phenolic compounds extracted by cold pressing method compared to the solvent method, as well as ethanol and petroleum ether solvents. The amount of phenolic compounds and antioxidant activity in yellow flax was higher than brown flax. Also, the amount of these compounds in the cold pressing method was higher than that of solvents.
Conclusion: The type of oil extraction method is highly impacts on the yield of extracted oil from flaxseeds. Brown flaxseed has significantly more oil and less phenolic and antioxidants compounds compared to yellow flaxseed.

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Aim and Background: Candida species are opportunistic pathogens that can be considered as the main cause of a wide range of diseases. Due to the increased resistance of these fungi to chemical drugs and also the adverse effects of these compounds on patients, it is necessary to replace these drugs with herbal compounds. In this study, the antifungal effect of aqueous and ethanolic extracts and essential oil of E. angustifolia on the growth of Candida albicans with fluconazole was compared.

Materials and Methods: In this laboratory study conducted in 1398 in Shahrekord Azad University Biotechnology Research Center, 80 candidate fungal samples were prepared from Parsian Hospital in Shahrekord and 50 Candida albicans samples were isolated by diagnostic tests. E. Angustifolia plants were obtained from Shahrekord Azad University Faculty of Agriculture. The extract was extracted by percolation and the essential oil was extracted by water distillation. The antifungal effect of E. angustifolia extracts along with E. angustifolia essential oil with fluconazole was compared on these isolates by disk diffusion and microdilution methods.

Results: The minimum and maximum diameter zone of inhibation obtained by disk diffusion method for E. angustifolia extracts, no growth halo formation with 1 and the lowest and maximum halo diameter for E. angustifolia essential oil were 6 and 37 mm. Therefore, the mean diameter of non-growth zone of inhibation for E. angustifolia extracts was 1 and for E. angustifoliathe essential oil was 23.4 mm. Comparison of the mean diameter of 25 mg fluconazole inhibition zone as control with an average of 16.26 mm shows a weaker antifungal performance and a significant difference compared to E. angustifolia essential oil. (P ≤ 0.05). The minimum inhibitory concentrations (MIC) of ethanolic and aqueous extracts of E. angustifolia and fluconazole were 4, 8, and 8 mg/ml, respectively; While the minimum fungicidal concentrations(MFC) were 8, 16, and 8 mg/ml, respectively; Showed a significant difference in inhibition of E. angustifoli ethanolic extract compared to 25 mg fluconazole disk (P ≤ 0.01). 

Discussion and Conclusion: According to the results of the above research, it seems that the ethanolic extract of E. angustifoliacan be used as a suitable drug candidate with better antifungal performance than fluconazole in the pharmaceutical industry.

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Aim and Background: The use of plants as medicine has always been considered. In the present study, the effect of aqueous extract collected in spring and autumn of Artemisia aucheri on the survival of HSV- 1 virus-infected cells was investigated.
Materials and Methods: In this study, the effect of aqueous extract of Artemisia aucheri in spring and autumn on the survival of Vero cell line after HSV- 1 infection at different times and concentrations was compared using TCID50 and MTT methods. The effect of aqueous extract of Artemisia aucheri at concentrations of 25, 50, 75, and 100 mg / ml on Vero cell line infected with HSV- 1 virus was performed for 24 hours in DMEM medium containing 2% (FBS) and then a dose of 50% Tissue Culture Infectious Dose(TCID50) was determined. Cell viability was also assessed by MTT assay at 2-, 0, 4, 8, and 24 hours.
Results: The dose of 50% TCID50 with different dilutions of spring and autumn aqueous extracts of Artemisia aucheri was determined on Vero cells infected with (MOI = 0.1) HSV- 1 virus by inverted microscope and compared by MTT method. Concentrations of 50, 75, µg/ml and 100 µg/ml of spring extract and concentrations of 50 and 75 µ g / ml of autumn extract significantly reduced viral infection. Among them, spring extract with a concentration of 75 µ g / ml showed the highest viral inhibition and cell survival. Also, a significant difference was observed between spring and autumn aqueous extracts of Artemisia aucheri on cell survival (r = 0.97, P =0.0002).
Conclusion: The results indicated that the spring aqueous extract of Artemisia aucheri has a significant anti-HSV- 1 antiviral effect compared to the autumn aqueous extract of Artemisia aucheri (A = 0.0001) (P = 0.0001).

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Aim and background: The use of medical herbs because of their reasonable price and availability is rapidly increasing but it faces many challenges. Researchers are trying to overcome these challenges by designing nano-drug delivery carriers such as liposome. In this study, a formulation of liposomal system containing Hedera Helix extract was synthesized and its toxicity on normal cells and physicochemical characteristics were evaluated.
Material and Method:  In the first step, extraction of Hedera Helix was done by succulent method. In the next step, nano-liposomes were prepared by thin film method from phosphatidylcholine and cholesterol and by using hydration inactive method the extract was loaded into them. Then the encapsulation rate and the release pattern were assayed by spectrophotometry method, the size of nanoparticles and their zeta potential were evaluated by the DLS, the non-interaction between the extract and the nanosystem was assessed by FT-IR technique and the morphology of the nanoparticles was examined by AFM microscope and finally the non-toxicity of the system on normal cells was assayed by MTT method.
Results: The results of this study showed that nano-liposomes containing Hedera Helix extract having 48.6 nm of diameter, 0.406 dispersion index, -37.3 ± 1.72 mV zeta potential and 82.67 ± 1.12 encapsulation efficiency are follow the slow releasing drug pattern. FTIR and AFM data demonstrated that there is no interaction between the extract and nanoliposomes and nanoliposomes have appropriate morphology. Finally, the results of the MTT assay confirmed the non-toxicity activity of nano-liposome.
Conclusion: In this study, physicochemical studies of nanosystems after loading Hedera Helix extract into liposomal nanosystems showed that the system is a slow-release and anionic type with acceptable size, morphology and acceptable encapsulation rate. The synthesized liposomes could be a suitable carrier for the Hedera Helix extract and increase its stability, solubility and thus improve its therapeutic performance.

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Aim and Background: Allergic properties of plants are an important factor in the production of natural herbicides. In this study, the microbial antimicrobial effects of aqueous extract of fennel on wheat germ germination factors were investigated.
Materials and Methods: In this experimental study, a randomized complete block design was performed in 4 treatments with 3 replications. The treatments of this experiment included 4 different concentrations of fennel aqueous extract (15, 10, 5, 5%). Measured parameters included germination percentage, seedling fresh weight, activity of alpha-amylase, catalase and malondialdehyde concentration.
Results: The results showed that the effect of experimental treatments on all measured traits of wheat grass was significant at the level of 1% probability. There was no significant difference with 5% treatment. With increasing fennel concentration, wheatgrass seedling weight also decreased. The highest weight was observed in control (0.11) and the lowest was observed in 15% fennel concentration (0.06). The highest and lowest alpha enzyme activity was observed. Amylase was observed in control treatment (4.53 nmol / min) and 15% fennel extract (1.67 nmol / min), respectively. The highest concentration of malondialdehyde in seedling tissue in 15% extract was 93% (nmol / gram )was observed. Decreased activity of antioxidant enzyme catalase was affected by increasing the concentration of fennel extract. Although the lowest activity of this enzyme was observed at a concentration of 15% (4.33 mg absorption per minute), this treatment differed from the treatment concentration of 10% (4.47 mg absorption per minute) It did not make sense.
Conclusion: According to the obtained results, it can be said that with increasing the concentration of fennel extract, the concentration of malondialdehyde also increased significantly. Aldehyde and decreased alpha-amylase activity.

 

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Aim and Background: Infectious diseases caused by bacterial agents are one of the most common causes of death worldwide. Many of these agents are resistant to one or more antibiotics, some are multidrug resistant, and others are resistant to almost all commonly used antibiotics. Antimicrobial, anticancer, and antioxidant compounds have been reported from the extracts of different buffers derived from different plant species. In this study, the antibacterial activity of the buffered extract and protein fractions of the buffered extract of Adenium obesum were investigated.
Material and Methods: In this research, firstly, the electrophoretic-chromatographic pattern of the buffered plant leaf extract and then the antibacterial properties of the buffered extract in denatured and non-denatured forms of proteins as well as its protein fractions in the required concentrations in terms of micrograms per milliliter in Laboratory conditions (in-vitro) were tested using the minimum inhibitory concentration (MIC) assay for Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli and ANOVA statistical analysis.
Results: Different protein bands were observed in the SDS-PAGE spectrum of crude buffer extract. In the chromatographic study, 12 main peaks were separated and collected, of which 9 fractions contained protein. The results of this study showed that crude buffer extract with undenatured proteins from 0.02 μg/ml and crude buffer extract with denatured proteins from 0.04 μg/ml had a significant inhibitory effect on Staphylococcus aureus and Escherichia coli. The results of this study on the protein fractions of crude buffer extract also showed different effects on the tested bacteria, including the highest inhibition rate of Gram-positive bacteria related to fraction 8 with an average inhibition of 25% at a protein concentration of 0.01 μg/mL and similarly, it was shown in gram-negative bacteria related to fraction 3 with 0.16 μg/mL gelate and fraction 10 with 0.01 μg/mL gelate with an average inhibition of 11 percent.
Conclusion: The results of this study showed for the first time that denatured and non-denatured buffer extract and its protein fractions 3, 8, and 10 have antibacterial properties.

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Background and Aim: Saccharomyces cerevisiae, known as baker's yeast, is used to produce yeast extract. The mentioned extract has wide applications in medicine, food industry, and most importantly as one of the main sources of food for microbiology cultures because it contains vitamins and substances needed for growth. The aim of this study was to develop a simple and profitable process for the production of yeast extract to prepare bacterial culture medium.
Materials and Methods: First, yeast extract was prepared from baker's yeast based on a simple protocol and as a result of changing temperature and high pressure, and after centrifugation, its liquid phase was converted into a solid form by means of a spray dryer, and then with a certain amount of agar from that microbial culture medium. It was prepared and then Gram-positive bacteria (Staphylococcus aureus ATCC 25923) and Gram-negative bacteria (Escherichia coli ATCC 25922) were used to check the ability and quality of bacteria to grow on it. To compare the growth rate of bacteria, standard culture media prepared from Merck (Germany) yeast extract and Mirmedia (Iran) yeast extract, Merck (Germany) tryptic soy agar was used.
Results: The obtained results indicate that the yeast extract from this study, as the only nutrient source for bacterial growth, is sufficiently available and the microorganisms are able to grow in that environment. Also, competitive competition with commercial yeast extracts can be used in the preparation of culture medium.
Conclusion: Considering the quality and rate of bacterial growth on the culture medium prepared in this study, and considering the wide application of yeast extract in the industry, and considering that no chemicals and enzymes were used in its preparation, the preparation of yeast extract in this way is of acceptable quality and affordable.