Tokat Gaziosmanpaşa Üniversitesi

Tannic acid, a naturally occurring plant polyphenol, is composed of a central glucose molecule derivatized at its hydroxyl groups with one or more galloyl residues. In the present paper, we examines the in vitro radical scavenging and antioxidant capacity of tannic acid by using different in vitro analytical methodologies such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination using by Fe3+–Fe2+ transformation method, superoxide anion radical scavenging by riboflavin–methionine-illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe2+) chelating activities. Also, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant radical scavenger compounds. Tannic acid inhibited 97.7% lipid peroxidation of linoleic acid emulsion at 15 μg/mL concentration. On the other hand, the above mentioned standard antioxidants indicated an inhibition of 92.2%, 99.6%, 84.6% and 95.6% on peroxidation of linoleic acid emulsion at 45 μg/mL concentration, respectively. In addition, tannic acid had an effective DPPH scavenging, ABTS+ radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, Fe3+ reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and trolox as references antioxidant compounds. The present study shows that tannic acid is the effective natural antioxidant component that can be used as food preservative agents or nutraceuticals.

The measurement of antioxidant capacity in fruits differs from that of other biological samples due to their low pH and very low lipophilic antioxidant capacity. In this report, we present a modified 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method for fruits and compare its performance with the other commonly used antioxidant methods of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). The antioxidant capacity and reaction kinetics of four phenolic compounds, two antioxidant standards, and five fruits were also investigated. The modified ABTS method prepared at a pH of 4.5 with sodium acetate buffer is highly stable and easily applied to fruit samples as compared to the standard (pH 7.4) version. The measured antioxidant capacity of samples varied with the assay method used, pH, and time of reaction. Traditional antioxidant standards (trolox, ascorbic acid) displayed stable, simple reaction kinetics, which allowed end point analysis with all of assays. Of the phenolic compounds examined, chlorogenic and caffeic acids exhibited the most complex reaction kinetics and reaction rates that precluded end point analysis while gallic acid and quercetin reached stable end points. All fruit extracts exhibited complex and varied kinetics and required long reaction times to approach an end point. Because the antioxidant capacity of fruit extracts is a function of the array of individual antioxidants present, accurate comparisons among fruit samples require that reaction times be standardized and of sufficient length to reach steady state conditions and that more than one assay be used to describe the total antioxidant activity of fruit samples.

The number of methods to measure the antioxidants in botanicals, foods, nutraceuticals and other dietary supplements has increased considerably in the last decade. Clove oil is obtained by distillation of the flowers, stems and leaves of the clove tree. In the present paper, clove oil was evaluated by employing various in vitro antioxidant assay such as α,α-diphenyl-β-picryl-hydrazyl free radical (DPPH) scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by Fe3+–Fe2+ transformation method, superoxide anion radical scavenging by riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe2+) chelating activities. Clove oil inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 μg/mL concentration. However, under the same conditions, the standard antioxidant compounds such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox demonstrated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 μg/mL concentration, respectively. In addition, clove oil had an effective DPPH scavenging, ABTS+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, these various antioxidant activities were compared to BHA, BHT, α-tocopherol and trolox as reference antioxidant compounds.

Fen, sosyal ve sağlık bilimlerinde yapılan ölçek uyarlama ve geliştirme çalışmalarının yapısal geçerliliğinin test edilmesi önemlidir. Geçerliliğin test edilmesi, doğrudan ölçülebilen gözlenen ve doğrudan ölçülemeyen gizil değişkenler olmak üzere, temelde iki değişken üzerine kurulan yapının veri tarafından sınanması mantığına dayanmaktadır. Bu çalışmada, Yapısal Eşitlik Modelleri (YEM) grubundan olan Doğrulayıcı Faktör Analizi (DFA) incelenmiştir. Teorik yapıya sahip olan DFA, Yapısal Eşitlik Modellerinin (YEM) bir türüdür ve uygulaması zor olan bir analiz yöntemidir. Ayrıca modelin veri tarafından sınanmasında, modelin uyumunu ortaya koyan uyum indekslerine yer verilmiştir. Çocuklarda Yeme Davranışı Anketi (ÇYDA) verileri kullanılıp, LISREL programının önerdiği farklı modeller sınanarak, model iyileştirmesi yapılmıştır. DFA ve uyum indeksleri uygulaması için Yılmaz ve ark. tarafından Mayıs-Haziran 2008 tarihleri arasında Gaziosmanpaşa Üniversitesi Tıp Fakültesi Pediatri Anabilim Dalı polikliniğine başvuran çocukların ve Tokat ilindeki anaokulu ve anasınıflarına devam eden öğrencilerin ebeveynlerine (n=468) uygulanmış olan Çocuklarda Yeme Davranışı Anketi (ÇYDA) verileri kullanılmıştır. Açıklayıcı Faktör Analizi (AFA) değerleri iyi düzeyde seyreden bir çalışmanın DFA sonuçlarının, AFA'da bulunandan daha kötü olduğu görülmektedir. Uygulamada Lisrel programının önerdiği düzeltmelerle üretilen 5 modelin sonuçlarına göre, modelin ürettiği uyum indekslerinde düzelme olduğu gösterilmiştir. Yapısal geçerliliğin sınanmasında, açıklayıcılığı göz önünde bulunduran AFA'ya ait bulguların, DFA ile sınanıp gerektiğinde model düzeltmesine gidilmesi, modeli daha kullanışlı ve geçerli kılacaktır.

The antioxidant properties of plants have been investigated, in the light of recent scientific developments, throughout the world due to their potent pharmacological activities and food viability. Basil (Ocimum basilicum L. Family Lamiaceae) is used as a kitchen herb and as an ornamental plant in house gardens. In the present study, the possible radical scavenging and antioxidant activity of the water (WEB) and ethanol extracts (EEB) of basil was investigated using different antioxidant methodologies: 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, scavenging of superoxide anion radical-generated non-enzymatic system, ferric thiocyanate method, reducing power, hydrogen peroxide scavenging and metal chelating activities. Experiments revealed that WEB and EEB have an antioxidant effects which are concentration-dependent. The total antioxidant activity was performed according to the ferric thiocyanate method. At the 50 microg/mL concentration, the inhibition effects of WEB and EEB on peroxidation of linoleic acid emulsion were found to be 94.8% and 97.5%, respectively. On the other hand, the percentage inhibition of a 50 microg/mL concentration of BHA, BHT and alpha-tocopherol was found to be 97.1%, 98.5% and 70.4% inhibition of peroxidation of linoleic acid emulsion, respectively. In addition, WEB and EEB had effective DPPH radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, reducing power and metal chelating activities. Additionally, these various antioxidant activities were compared with BHA, BHT and alpha-tocopherol as reference antioxidants. The additional total phenolic content of these basil extracts was determined as the gallic acid equivalent and were found to be equivalent.

To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug-like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection.

Significance We sequenced the genome and transcriptomes of the wild olive (oleaster). More than 50,000 genes were predicted, and evidence was found for two relatively recent whole-genome duplication events, dated at approximately 28 and 59 Mya. Whole-genome sequencing, as well as gene expression studies, provide further insights into the evolution of oil biosynthesis, and will aid future studies aimed at further increasing the production of olive oil, which is a key ingredient of the healthy Mediterranean diet and has been granted a qualified health claim by the US Food and Drug Administration.

Cadmium (Cd) is a significant ecotoxic heavy metal that adversely affects all biological processes of humans, animals and plants. Exposure to acute and chronic Cd damages many organs in humans and animals (e.g. lung, liver, brain, kidney, and testes). In humans, the Cd concentration at birth is zero, but because the biological half-life is long (about 30 years in humans), the concentration increases with age. The industrial developments of the last century have significantly increased the use of this metal. Especially in developing countries, this consumption is higher. Oxidative stress is the imbalance between antioxidants and oxidants. Cd increases reactive oxygen species (ROS) production and causes oxidative stress. Excess cellular levels of ROS cause damage to proteins, nucleic acids, lipids, membranes and organelles. This damage has been associated with various diseases. These include cancer, hypertension, ischemia/perfusion, cardiovascular diseases, chronic obstructive pulmonary disease, diabetes, insulin resistance, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, asthma, skin diseases, chronic kidney disease, eye diseases, neurodegenerative diseases (amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington disease). Natural antioxidants are popular drugs that are used by the majority of people and have few side effects. Natural antioxidants play an important role in reducing free radicals caused by Cd toxicity. Our goal in this review is to establish the relationship between Cd and oxidative stress and to discuss the role of natural antioxidants in reducing Cd toxicity.

Abstract Measurements from the CMS experiment at the LHC of dihadron correlations for charged particles produced in PbPb collisions at a nucleon–nucleon centre-of-mass energy of 2.76 TeV are presented. The results are reported as a function of the particle transverse momenta ( p T ) and collision centrality over a broad range in relative pseudorapidity (Δ η ) and the full range of relative azimuthal angle (Δ ϕ ). The observed two-dimensional correlation structure in Δ η and Δ ϕ is characterised by a narrow peak at (Δ η ,Δ ϕ )≈(0,0) from jet-like correlations and a long-range structure that persists up to at least |Δ η |=4. An enhancement of the magnitude of the short-range jet peak is observed with increasing centrality, especially for particles of p T around 1–2 GeV/ c . The long-range azimuthal dihadron correlations are extensively studied using a Fourier decomposition analysis. The extracted Fourier coefficients are found to factorise into a product of single-particle azimuthal anisotropies up to p T ≈3–3.5 GeV/ c for at least one particle from each pair, except for the second-order harmonics in the most central PbPb events. Various orders of the single-particle azimuthal anisotropy harmonics are extracted for associated particle p T of 1–3 GeV/ c , as a function of the trigger particle p T up to 20 GeV/ c and over the full centrality range.

Despite the plethora of m-learning acceptance studies, few have tackled the importance of examining the actual use of m-learning systems from the lenses of social influence, expectation-confirmation, and satisfaction. Additionally, most of the prior technology adoption literature tends to use the structural equation modeling (SEM) technique in analyzing the structural models. To address these limitations, this study extends the technology acceptance model (TAM) with the expectation-confirmation model (ECM) and social influence to predict the actual use of m-learning systems. A comparative approach using the partial least squares-structural equation modeling (PLS-SEM) and machine learning algorithms was employed to test the proposed model with data collected from 448 students. The results revealed that both techniques have successfully provided support to all the hypothesized relationships of the research model. More interesting, the J48 classifier has performed better than the other classifiers in predicting the dependent variable in most cases. The employment of a comparative analytical approach is believed to add a significant contribution to the information systems (IS) literature in general, and the m-learning domain in specific.

BACKGROUND: An accurate and specific diagnosis prevents the recurrences of low back pain and chronic spinal pain. The physical examination is the most useful tool to diagnosis. The examiner must aim to determine the exact tissue that pain arises from to make the specific diagnosis. Lumbar disc herniation is 1 disease that physical examination, symptoms, and findings on imaging technique do not always correlate with each other. The Straight Leg Raising (SLR) test has been used as the primary test to diagnosis lumbar disc herniations and found to have high correlation with findings on operation since its sensitivity is high in only disc herniations leading to root compression that may eventually need operation. More sensitive test, like the Slump, might be used in herniations in which the SLR is negative. The Slump test is really a variant of the SLR and the Lasègue's tests performed in the seated position and is a progressive series of maneuvers designed to place the sciatic nerve roots under increasing tension. At each step in the procedure, the patient informs the examiner what is being felt and whether radicular pain is produced. As a result, the Slump test applies traction to the nerve roots by incorporating spinal and hip joint flexion into the leg raising and would warn the examiner of the presence of nerve root compression when there is a negative SLR test. OBJECTIVES: This study measured the sensitivity and specificity of the Slump test and compare it with the SLR test in patients with and without lumbar disc herniations. METHODS: A prospective case control study of 75 patients with complaints suggestive of lumbar disc herniation was carried out in the outpatient clinics of the neurosurgery department of a state teaching hospital. Seventy-five referred or self-admitted patients with low back, leg, or low back and leg pain who had results of magnetic resonance imaging (MRI) of the lumbar spine were included in the study. Thirty-eight patients had signs of herniation demonstrated by MRI. Control patients (n = 37) had no disc bulges or herniations on MRI. Both the Slump and SLR tests were performed during the assessment of all the patients by the second author. The MRI results were assessed and recorded by the first author. RESULTS: The Slump test was found to be more sensitive (0.84) than the SLR (0.52) in the patients with lumbar disc herniations. However, the SLR was found to be a slightly more specific test (0.89) than the Slump test (0.83). CONCLUSION: The Slump test might be used more frequently as a sensitive physical examination tool in patients with symptoms of lumbar disc herniations. In contrast, owing to its higher specificity, the SLR test may especially help identify patients who have herniations with root compression requiring surgery.

The use of synthetic insecticides has been a solution to reduce mosquito-borne disease transmission for decades. Currently, no single intervention is sufficient to reduce the global disease burden caused by mosquitoes. Problems associated with extensive usage of synthetic compounds have increased substantially which makes mosquito-borne disease elimination and prevention more difficult over the years. Thus, it is crucial that much safer and effective mosquito control strategies are developed. Natural compounds from plants have been efficiently used to fight insect pests for a long time. Plant-based bioinsecticides are now considered a much safer and less toxic alternative to synthetic compounds. Here, we discuss candidate plant-based compounds that show larvicidal, adulticidal, and repellent properties. Our discussion also includes their mode of action and potential impact in mosquito disease transmission and circumvention of resistance. This review improves our knowledge on plant-based bioinsecticides and the potential for the development of state-of-the-art mosquito control strategies.

This article discusses the growing need of energy in both developed and developing countries, and the acute population growth, which will exceed 10 billion by the year 2050. How can a world of 10 billion people be provided with adequate supplies of energy, cleanly, safely and substantially? There is a growing consensus that renewable energy sources will be a very important part of the answer. The growing interest in renewables has been prompted, in part, by increasing concern over the pollution, resource depletion and possible climate change implications of our continuing use of conventional fossil and nuclear fuels. Recent technological developments have also improved the cost-effectiveness of many of the renewables, making their economic prospects look increasingly attractive. It describes the achievement and progress made in hydropower, biomass conversion, geothermal, solar thermal technology, wind energy conversion, and the increasing usage of photovoltaics. It is evident that global warming is setting in and is going to change the climate, as well as the terrain of many countries, unless drastic measures are taken. The Kyoto meeting emphasized the importance of limiting CO2 emissions and to abide by some form of agreement to reduce emissions. The present study concludes that renewable energy penetration into the energy market is much faster than was expected in recent years and by 2030, 15–20% of our prime energy will be met by renewable energy.

In this work, we define a fuzzy soft set theory and its related properties. We then define fuzzy soft aggregation operator that allows constructing more efficient decision making method. Finally, we give an example which shows that the method can be successfully applied to many problems that contain uncertainties.

OBJECTIVE: The adverse effects of proton pump inhibitors (PPIs) have been documented for pneumonia; however, there is no consensus regarding whether the use of PPIs might be harmful regarding the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this regard, we aimed to measure the potential associations of the current use of PPIs with the infection rates of COVID-19 among patients who underwent SARS-CoV-2 testing. DESIGN: Data were derived from a Korean nationwide cohort study with propensity score matching. We included 132 316 patients older than 18 years who tested for SARS-CoV-2 between 1 January and 15 May 2020. Endpoints were SARS-CoV-2 positivity (primary) and severe clinical outcomes of COVID-19 (secondary: admission to intensive care unit, administration of invasive ventilation or death). RESULTS: In the entire cohort, there were 111 911 non-users, 14 163 current PPI users and 6242 past PPI users. After propensity score matching, the SARS-CoV-2 test positivity rate was not associated with the current or past use of PPIs. Among patients with confirmed COVID-19, the current use of PPIs conferred a 79% greater risk of severe clinical outcomes of COVID-19, while the relationship with the past use of PPIs remained insignificant. Current PPI use starting within the previous 30 days was associated with a 90% increased risk of severe clinical outcomes of COVID-19. CONCLUSION: Patients taking PPIs are at increased risk for severe clinical outcomes of COVID-19 but not susceptible to SARS-CoV-2 infection. This suggests that physicians need to assess benefit-risk assessments in the management of acid-related diseases amid the COVID-19 pandemic.

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.

Introduction; Pulmonary fibrosis is a frequently reported COVID-19 sequela in which the exact prevalence and risk factors are yet to be established. This meta-analysis aims to investigate the prevalence of post-COVID-19 pulmonary fibrosis (PCPF) and the potential risk factors. Methods; CINAHL, PubMed/MEDLINE, Cochrane Library, Web of Science, and EMBASE databases were searched to identify English language studies published up to December 3, 2021. Results; The systematic search initially revealed a total of 618 articles - of which only 13 studies reporting 2018 patients were included in this study. Among the patients, 1047 (51.9%) were male and 971 (48.1%) were female. The mean age was 54.5 years (15-94). The prevalence of PCPF was 44.9%. The mean age was 59 years in fibrotic patients and 48.5 years in non-fibrotic patients. Chronic obstructive pulmonary disease was the only comorbidity associated with PCPF. Fibrotic patients more commonly suffered from persistent symptoms of dyspnea, cough, chest pain, fatigue, and myalgia (p-value < 0.05). Factors related to COVID-19 severity that were associated with PCPF development included computed tomography score of ≥18, ICU admission, invasive/non-invasive mechanical ventilation, longer hospitalization period, and steroid, antibiotic and immunoglobulin treatments (p-value < 0.05). Parenchymal bands (284/341), ground-glass opacities (552/753), interlobular septal thickening (220/381), and consolidation (197/319) were the most common lung abnormalities found in fibrotic patients. Conclusion, About 44.9% of COVID-19 survivors appear to have developed pulmonary fibrosis. Factors related to COVID-19 severity were significantly associated with PCPF development.

The primary objective of this paper is to provide a review of research on argumentation in science education based on publications from 1998 to 2014 in three science education journals. In recent years, the teaching and learning argumentation (i.e. the coordination of evidence and theory to support or refute an explanatory conclusion, model or prediction) has emerged as a significant educational goal. Argumentation is a critically important discourse process in science and it should be taught and learned in the science classroom as part of scientific inquiry and literacy. Argumentation stresses the evidence-based justification of knowledge claims, and it underpins reasoning across STEM domains. Our aim in this study was to investigate how argumentation has been positioned within the publications of three top academic journals: Science Education, International Journal of Science Education, and Journal of Research in Science Teaching. A methodology for content analysis of the journals is described using quantitative and qualitative techniques. One of the contributions of our analysis is the illustration that researchers studying argumentation from a linguistic perspective have been emphasizing related concepts in different ways. While the emphasis has been on discourse and discussion across all journals, the related concepts of talk, conversation, dialogue and negotiation were observed to a lesser extent. Likewise, the fine-level analysis of the key epistemic concepts such as reasoning, evidence and inquiry indicates variation in coverage. The findings can provide evidence-based indicators for where more emphasis needs to be placed in future research on argumentation, and in particular they can provide guidelines for journals in soliciting articles that target underemphasized aspects of argumentation in science education.

This study investigated role of the self-directed learning skills, metacognitive awareness, and 21st century skills and competences in predicting readiness for online learning during the COVID-19 pandemic. 21st Century Skills and Competences Scale, Self-Directed Learning Skills Scale, Metacognitive Awareness Inventory, and Readiness for Online Learning Scale were used to collect data from 834 prospective teachers. Structural equation modelling (SEM) results indicated that self-directed learning skills, metacognitive awareness, and 21st century skills and competences positively predict prospective teachers’ readiness for online learning. These findings suggested that enhancing prospective teachers’ self-directed learning, metacognitive awareness, and 21st century skills and competences may promote their readiness for online learning.

Heavy metal toxicity is one of the major abiotic stresses caused by physiological and biochemical changes. Plants have evolved various phytochemical defense mechanisms to cope with this abiotic stress conditions. Phenolic compounds are one of the stress responses and have multiple roles in respect to adaptation of plants to the environment. In the present study, we aimed to evaluate the differential accumulation of various phenolics with HPLC in the leaves of corn exposed to increasing heavy metal doses in the plant growth medium. The application of Cd, Cu, and Pb increased the total phenolics in all treatments compared to control groups. Chlorogenic acid and rutin were the main phenolic compounds in respect to quantifying. However, the contents of caffeic acid, ferulic acid, and vanillic acid were comparatively lower than chlorogenic acid and rutin in all samples. The content of chlorogenic acid significantly increased and rutin slightly increased in the treatment of the heavy metals. The levels of caffeic acid and ferulic acid significantly decreased in all exposures of heavy metals compared to control groups. The content of vanillic acid changed according to heavy metal types and doses in the leaves of corn, and the low doses of Pb and Cd increased the level of vanillic acid. We show that there is a positive correlation with the total phenolic content and chlorogenic acid when the corn is exposed to Pb. Moreover, there are negative correlations between total phenolic compound and caffeic acid, ferulic acid in the application of Cu and Cd.