Open Access Short Research Article

Anti-inflammatory Activity of Butanolic Extract of Albizia lebbeck

Antony de Paula Barbosa

European Journal of Medicinal Plants, Page 1400-1407
DOI: 10.9734/EJMP/2014/11743

Albizia lebbeck is a tree widely distributed in India and is also found in South Africa, South America and Australia. As in Indian traditional system as folk medicine, this plant is used to treat several inflammatory pathologies such as asthma, arthritis and burns. Study of other species this same genus has demonstrated an anti-inflammatory activity of crude extract, which, in some work has been attributed to the presence of saponins. In order to confirm these findings a study of phytochemical profile was realized and a rich extract in saponins, butanolic extract, was obtained and its anti-inflammatory activity was evaluated through measured by inhibition of carrageenan-induced mouse paw oedema, using dexamethasone as reference compound. The extract exhibited a moderate control of the both phase of inflammation, provoking an inhibition of edema formation. However, the butanolic extract exhibited lesser activity than reference compound dexamethasone. The results obtained suggest a significant antiinflamatory property of the butanolic extract of Albizia lebbeck, justifying the use of this plant in the traditional medicine for the treatment of inflammatory conditions and confirm their saponins as bioactive product.

 

Open Access Minireview Article

Current Perspectives on Use of Aloe vera in Dentistry

Erika Tayal, Divesh Sardana, K. R. InduShekar, Bhavna G. Saraf, Neha Sheoran

European Journal of Medicinal Plants, Page 1408-1419
DOI: 10.9734/EJMP/2014/10843

Introduction: Aloe vera is known from centuries as a medicinal plant. It’s a wonder plant with a lot of health benefits and hence often been called the 'natural healer'. It is a tropical plant that flourishes in warm and dry climate and looks like a cactus with fleshy thorny leaves. There are around 400 species of Aloe, but it is the Aloe barbadensis Miller (Aloe vera or "true aloe") plant which has been used most (found mainly in Asia, Africa and other tropical areas) because of its medicinal uses like moisturizing, anti-inflammatory, antioxidant, anticancer, antibacterial, antiviral and antifungal properties.

Medicinal Uses: Aloe vera has its uses in various systemic conditions like skin disorders (e.g. psoriasis), arthritis, asthma, digestive and bowel disorders, diabetes and lowering lipid levels in hyper-lipidemic patients. It has also be used as a detoxifying agent, for topical application of first and second degree burns, as a immune enhancer, in Alzheimer’s disease and in various cosmetic, medical and dental products.

Dental Uses: This wonder plant has also been used in dentistry for its beneficial properties in various conditions like lichen planus, apthous stomatitis, oral submucous fibrosis, pulpotomy of primary teeth, prevention of dry sockets, obturation of primary teeth, disinfection of irrigation units, bleeding and painful gums, disinfection of gutta percha cones, burning mouth syndrome and in radiated head and neck cancer patients. The purpose of this article is to highlight the role of A. barbadensis in various branches of dentistry and its potential future role.

Conclusion: Aloe vera indeed has a definitive useful role in dentistry. However, future researches should be aimed to determine its method of preparation, optimal concentration, time of application and effects on the oral cavity.

 

Open Access Original Research Article

Antiplasmodial Potential of Traditional Medicinal Plant Thlaspi arvense

Neha Sylvia Walter, Upma Bagai

European Journal of Medicinal Plants, Page 1378-1387
DOI: 10.9734/EJMP/2014/11584

Aim: Antiplasmodial potential of traditional medicinal plant Thlaspi arvense against Plasmodium falciparum in vitro has been evaluated. Cytotoxicity of plant extract against HeLa cell lines and normal fibroblasts has also been observed.

Place and Duration of the Study: Department of Zoology, Panjab University, Chandigarh, India, between May 2013 to April 2014.

Materials and Methods: Ethanolic whole plant extract of Thlaspi arvense (EWETA) was analyzed for its phytochemical constituents. In vitro cytotoxicity was determined colorimetrically by MTT assay. WHO protocol, based on assessment of schizont maturation inhibition, was employed for the evaluation of in vitro antiplasmodial activity of plant extract.

Results: Phytochemical screening of EWETA revealed the presence of diterpenes, triterpenes, steroids, anthraquinones and phytosterols. EWETA was observed to inhibit schizont maturation of both chloroquine-sensitive (MRC-2) and resistant (RKL-9) strains of P. falciparum with IC50<5µg/ml and =5µg/ml respectively. The extract was revealed to be safe against both HeLa cells and normal fibroblasts with CC50>1000µg/ml. Selectivity index for Thlaspi arvense was calculated to be >200 and =200 both for chloroquine-sensitive and chloroquine-resistant strains of P. falciparum with both HeLa and normal fibroblasts.

Conclusion: Plant extract possesses considerable in vitro antimalarial activity with high selectivity index (SI>10) pointing field pennycress to be an active antimalarial. Hence, present study provides scientific evidence for traditional usage of the plant as an antipyretic agent.

 

Open Access Original Research Article

Effect of Cooking on Proximate, Phytochemical Constituents and Hematological Parameters of Tetracarpidium conophorum in Male Albino Rats

V. O. Apeh, C. V. Agu, V. N. Ogugua, P. N. Uzoegwu, E. G. Anaduaka, T. E. Rex, I. S. Agbalu

European Journal of Medicinal Plants, Page 1388-1399
DOI: 10.9734/EJMP/2014/11352

Aims: To determine the effect of cooking on proximate, phytochemical constituents and their changes in hematological parameters.

Study Design: Determination of proximate and quantitative phytochemical constituents of the cooked and raw T. conophorum (CTC and RTC respectively) nut and the effect of the nut on the hematological indices on male albino rats fed with the cooked and raw diet formulations of the nut for 30 days period.

Methodology: Rats were divided into six groups of five rats each. Each feed and walnut was weighed and mixed in the ratio of 1:1 before administration. Group A: Normal animal feed, Group B: Mixture of animal feed and cooked nut (ratio of 1:1).

Group C: Mixture of animal feed and the raw nut (ratio of 1:1), Group D: 100% of the cooked nut, Group E: 100% of the raw nut while Group F: Mixture of raw nut and cooked (ratio of 1:1).

Result: The result showed that crude protein, carbohydrate and crude fibre contents of RTC were significantly higher (P<0.05) than the CTC. While the percentage moisture, fat and ash content of the CTC were significantly higher than the RTC. The quantitative phytochemical analysis revealed that there was no significant difference (P>0.05) between the alkaloid and flavonoid contents of RTC and CTC. Tannin, saponin, glycosides, hydrogen cyanide and steroid contents of RTC were significantly higher (P<0.05) than the CTC while terpenoid content of the CTC was significantly higher (P<0.05) than of the the RTC. The hemoglobin values showed no significant difference between the test groups and control group. The neutrophil values of group E and F were significantly higher (P<0.05) when compared with the control group. Rats in group E had a significant decrease (P<0.05) in lymphocyte value as against the control. Total WBC levels in group B, C and F recorded a significant decrease (P<0.05) when compared with the control.

Conclusion: The study suggests that processing cooking affects some nutrient constituents and some hematological parameters.

 

Open Access Original Research Article

Casearia sylvestris Swartz Extract Release Using Natural Rubber Latex Biomembranes as Carrier

F. A. Borges, A. Trecco, N. R. Barros, M. C. R. Miranda, E. G. Pierri, A. G. Santos, R. D. Herculano

European Journal of Medicinal Plants, Page 1420-1430
DOI: 10.9734/EJMP/2014/12039

The Natural Rubber Latex (NRL) from Hevea brasiliensis has shown promise in biomedical applications due to its low cost, easy handling, mechanical properties and biocompatibility, being used for bone regeneration and wound healing due to its natural stimulus to angiogenesis. The aim of this work was to incorporate Casearia sylvestris Sw. extract in NRL biomembranes and study its release behavior. The complex membrane-extract has as object of study a new approach of using C. sylvestris extract in the treatment of wounds, for possessing antiseptic activity, anti-inflammatory and analgesic properties. The C. sylvestris species (Salicaceae), popularly known as "guaçatonga", presents great distribution and is used in folk medicine as antiulcer, wound healing, anti-snake venom, properties which have been proven and related to clerodane diterpenes (casearins A-X). The release rate of C. sylvestris compounds from extract-membrane complex was monitored and analyzed using the method of optical spectroscopy (UV-VIS). The release varied with temperature ranging from 14 to 33 days, releasing more than 90%, with an interesting and promising biomedical application, such as wound healing and burns.

 

Open Access Original Research Article

Improvement Germination and Conversion of Somatic Embryos and Production of Normal Plantlets in Ferula Assa-foetida L. (A Rare Medicinal Plant)

Shirin Roozbeh, Mahmoud Otroshy

European Journal of Medicinal Plants, Page 1447-1461
DOI: 10.9734/EJMP/2014/10215

Secondary somatic embryogenesis leads to the formation of abnormal somatic embryos and produces abnormal seedlings. Normal plants are difficult to obtain from these embryos, due to the asynchronous maturation of the embryogenic tissues and low germination and conversion rates. The effects of some media additives and different strengths of MS medium on germination and plantlet formation of in vitro derived somatic embryos of Ferula Assa-foetida were studied. The highest number of normal embryos was observed in MS medium containing 30g/l sucrose with 0.5% or 1% AC and in MS medium supplemented with PEG and 0.5% or 1% AC. The treatments of MS medium with 30g/l sucrose and 0.5% AC × MS medium containing sorbitol and MS medium containing PEG and 1% AC × ½ MS had maximum number of normal germinated embryos without secondary somatic embryogenesis (SSE). In some of the treatments the embryos were converted better than the others, such as; the interaction effect of MS medium with 30g/l sucrose and 0.5% AC× MS, MS medium with 30g/l sucrose × MS medium with glutamine. Using different strength of MS medium and presence of some media additives is effective on germination and conversion of somatic embryos into normal plantlet. Presence of Activated Charcoal in the culture medium can reduce secondary somatic embryogenesis.

Open Access Original Research Article

Antimicrobial Activity of Tetradenia riparia (Hochst.) Lamiaceae, a Medicinal Plant from Tanzania

Efrem- Fred A. Njau, Jane- Mary Alcorn, Joram Buza, Manuel Chirino-Trejo, Patrick Ndakidemi

European Journal of Medicinal Plants, Page 1462-1478
DOI: 10.9734/EJMP/2014/11370

Aims: To evaluate the antibacterial activity of Tetradenia riparia crude extracts against Escherichia coli, Staphylococcus aureus and Enterococcuss faecalis. The phytochemicals that are responsible for the bioactivity were also screened.

Study Design: In vitro assay of antibacterial properties.

Place and Duration of Study: Samples were collected from Njari village at Uru North in Moshi district located in north eastern Tanzania. Extraction and phytochemical analyses were conducted at the College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada. Antimicrobial assay was carried out at Department of Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada between March 2013 and August 2013.

Methodology: Agar well diffusion test was used to determine antimicrobial activity of the plant extracts. Ethanol, methanol, hexane and distilled water were used as extracting solvents. These extracting solvents were removed by vacuo evaporator. The resulting concentrated gummy-like materials were dissolved in Dimethysulfoxide (10% DMSO). Chemical tests were used to determine the group of phytochemicals present in the sample extracts.

Results: Sensitivity testing results indicated that S. aureus was found to be more sensitive than E. coli and E. faecalis. Tetradenia riparia methanolic extracts from the root were the most active with zone of inhibition values of 29.33±0.88mm, 21.33±0.33mm and 20.0±1.0mm in diameter against S. aureus, E. faecalis and E. coli respectively. The relative inhibitory zone diameter (RIZD) was calculated. The highest percentage values of relative inhibition zone diameter of 84±5.06% (S. aureus) and 76±6.86% (E. coli) were demonstrated by T. riparia root methanolic extracts. However, T. riparia leaf and root extracts using hexane as well as leaf extracts using water did not show any antibacterial activity against E. faecalis. Root methanolic and ethanolic extracts demonstrated the minimum inhibitory concentrations ranging from 1.25mg/ml to 5.00mg/ml. Phytochemical screening of crude extracts from leaf and root of T. riparia revealed the presence of alkaloids, flavonoids, phenolics, saponins, tannins and sterols.

Conclusion: The study findings suggest likelihood of designing and developing potentially active antibacterial drug from T. riparia. Further studies should concentrate on the investigations of not only leaf but also the root part of the plant.

 

Open Access Original Research Article

Ethnomedicinal Survey of Botanicals Used by Herbal Practitioners in Yagba East Local Government of Kogi State, Nigeria

B. P. Olatunji, D. O. Ajibola, E. O. Adebayo, E. E. Nyong, J. O. Moody

European Journal of Medicinal Plants, Page 1479-1488
DOI: 10.9734/EJMP/2014/10393

Despite the great values and importance of ethnobotany to the lives of men, a large percentage of distribution and utilization are yet to be identified and appropriately documented. This survey aims at identifying and documenting the medicinal plants as well as their methods of formulation for use among the people of Kogi State, Nigeria. A combination of semi-structured open ended questionnaires and guided interactive survey techniques were used to obtain information as a total of 70 respondents were interviewed. Guided direct field observation method was used for collection of cited specimen which was identified in accordance with standard taxonomic practices. Descriptive statistics were used for data analysis. A total of 53 medicinal plant species belonging to 36 families were identified among others as reported in this survey with the Fabaceae family being the most abundantly utilized. Leaves (47.8%), fruits (19.5%) and stem bark (10.8%) are most frequently employed and the remedies are administered mostly as decoction (s) and infusion. Ailments such as gynecological disorders, mental and nervous malfunctioning, GIT infection and disturbances, and fever, are mostly reported as commonly treated. The survey provides a veritable source of information and a reliable documentation of medicinal plants from flora of Nigeria and their uses. A further study is suggested on pharmacological evaluations of reported activities and pharmacological acceptable packaging of these medicaments. 

 

Open Access Original Research Article

Loranthus micranthus Leaves Extract Attenuates Risk Factors of Cardiovascular Disease in Fructose Fed Rats

E. O. Ajani, O. O. Ogunlabi, O. Akinwande, B. O. Adegbesan

European Journal of Medicinal Plants, Page 1489-1500
DOI: 10.9734/EJMP/2014/12557

Aims: Today there are concerns about possible adverse effects of dietary sugars.  This study was set up to compare the metabolic dysfunction induced by dietary fructose in male rats with that of the female, investigate the modulatory effect of Loranthus micranthus on this dysfunction and compare this with that of nifedipine. 

Study Design:  Fifty six rats assigned to four groups of 7 male and 7 females (hosted in different cages) per group were used in the study. The water of group B, C and D rats were supplemented with 10% fructose for the first two 2 weeks and was later increased to 20%, 30% and 40% fructose after every 2 other weeks respectively. Nifedipine (10mg/Kg) was administered to group C while L. micranthus (600mg/Kg) was orally administered to group D. All administrations were carried out daily as a single dose after which the rats were sacrificed and the serum analyzed for the lipid components. The serum glucose level was also measured after every 2 weeks interval. 

Results: Fructose administration increased serum total cholesterol, triglyceride, LDL-C, VLDL-C, atherogenic and coronary risk indexes but decreased serum HDL-C significantly.  The increase was greater in the male rats.  Serum glucose was not altered during the first 6 weeks of study but was observed to be significantly increased above the initial value after 8 weeks of study. Both L. micranthus and nifedipine prevented this metabolic dysfunction but the effect was more pronounced with L. micranthus extract. 

Conclusion: The study concludes that male subjects are more prone to metabolic dysfunction of fructose than the female group and that L. micranthus is efficacious in preventing this defect in both male and female subject.

 

Open Access Original Research Article

Evaluation of Antidiabetic and the Effect of Methanolic Leaf Extract of Jatropha curcas on Some Biochemical Parameters in Alloxan-induced Diabetic Male Albino Rats

Momoh Johnson, Longe Adeteju Olufunmilayo, Campbell Charles Adegboyega, Omotayo Mutiat Adetayo

European Journal of Medicinal Plants, Page 1501-1512
DOI: 10.9734/EJMP/2014/12500

Aims: The study evaluates the antidiabetic, and the effect of methanolic leaf extract of Jatropha curcas on some biochemical parameters in alloxan-induced diabetic male albino rats (Wistar strain).

Place and Duration of Study: The study was carried out for ten months in 2012 in Biochemistry Laboratory, Department of Science Laboratory Technology (Biochemistry Unit), School of Technology, Lagos State Polytechnic, Ikorodu, Lagos- Nigeria, and Department of Hematology and blood transfusion, APIN Clinic LUTH, University of Lagos, Nigeria.

Methodology: Qualitative phytochemical analysis of the extract were carried out to determine the presence of secondary metabolites present in the extract of Jatropha curcas.

The animals were weighed using weighing balance, there blood sugar levels were assayed using Accu-chek Active Glucometer and blood glucose test strips. The hematological parameters were determined using BC-3200 Auto Hematology Analyzer, lipid profiles, total protein, total bilirubin and liver biomarker enzymes were assayed using Randox kits.

Results: The phytochemical constituents of J. curcas extract indicate the presence of secondary metabolites like tannins, saponins, flavonoids etc. The weight of diabetic untreated rats were significantly (P<0.05) reduced when compared to other groups. The animals treated with glibenclamide, 150 and 250mg/Kg  body weight of J. curcas  extract showed significant decrease (P<0.05) of blood sugar level compared to the untreated rats. The extract does possess hematopoietic activity and is not hematotoxic.  J. curcas had hypolipidemic effect and can be used in the management of diabetes. The extract significantly reduced (P<0.05) total bilirubin and liver biomarker enzymes (AST, ALT and ALP).

Conclusion: The results show that the methanolic leaf extract of Jatropha curcas can be used in the management of diabetes. 

 

Open Access Original Research Article

Individual and Combined Antibacterial Activity of Crude Extracts from Medicinal Plants Carissa spinarum Linn and Carica papaya Linn

Clarence Rubaka, Patrick Ndakidemi, Hamisi M. Malebo, Francis Shahada

European Journal of Medicinal Plants, Page 1513-1523
DOI: 10.9734/EJMP/2014/10599

Aim: To assess inhibitory effect of extracts, alone and in combination, from Carissa spinarum Linn (C. spinarum L.) and Carica papaya Linn (C. papaya L.) on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The combined extracts used were C. papaya L leaves petroleum ether extract/C. spinarum L root methanolic extract (CPLP/CSRM), C. spinarum L leaves petroleum ether extract/C. papaya L seed ethanolic extract (CSLP/CPSE), C. spinarum L root ethanolic extract/C. papaya L leaves ethanolic extract (CSRE/CPLE), C. papaya L root ethanolic extract/C. spinarum L bark ethanolic extract (CPRE/CSBE) and C. papaya L leaves methanolic extract/C. spinarum L leaves methanolic extract (CPLM/CSLM).

Study Design: In vitro antibacterial assay.

Place and Duration of Study: Samples were collected from Samunge village at Loliondo in Ngorongoro district located in northern Tanzania. Antimicrobial bioassay was carried out at the Department of Molecular Biology and Biotechnology, University of Dar-es-Salaam, between March 2013 and June 2013.

Methodology: The broth micro dilution method was used to determine minimum inhibition concentration (MIC). Fractional inhibitory concentrations were calculated from MICs of individual and combined extracts to determine interactions.

Results: Plant extracts demonstrated MICs ranging from 312 to 5000 μg/ml. The combination of plant extracts against S. aureus resulted into antibacterial activity of CPSE, CPRE, CPLM, CSLM and CPLP extracts to increase by 4-, 2-, 4-, 4-, and 2-fold, respectively. Activity of CSLP, CPLM and CSLM increased by 2-fold against E. coli. Synergy was demonstrated by CPLM/CSLM against S. aureus. Some combinations were additive including CPRE/CSBE, CPLP/CSRM and CSLP/CPSE against S. aureus and CSLP/CPSE, CPRE/CSBE, CPLM/CSLM against E. coli. Nevertheless, antagonism was demonstrated by CSRE/CPLE, CPLP/CSRM against E. coli and CSLP/CPSE and CSRE/CPLE against S. aureus.

Conclusion: This study revealed the importance of using plant-based antibacterial agents in combined therapy to increase efficacy. Extracts of C. spinarum L and C. papaya L could be a source of antibacterial agents when utilized in combination therapy for patients with severe E. coli and staphylococcal infections. These predictors, however, need to be validated to improve their quality.

 

Open Access Original Research Article

Chemical Composition of the Leaf Essential Oils of Croton zambesicus Müll.-Arg. Grown in Lagos, South-West Nigeria

Akintayo L. Ogundajo, Isiaka A. Ogunwande, Hammed G. Gbadamosi, Rukayat Giwa, Guido Flamini

European Journal of Medicinal Plants, Page 1524-1533
DOI: 10.9734/EJMP/2014/7099

The chemical composition of the leaf essential oil of Croton zambesicus Müll.-Arg., collected from Agbara-Lagos, Nigeria, was analysed by means of Gas chromatography-flame ionization detector (GC-FID) and Gas chromatography coupled with Mass spectrometry (GC-MS). Sixty constituents accounting for 98.9% of the total oil contents were identified from the oil sample. The classes of compounds identified in the oil were monoterpene hydrocarbons (35.3%), oxygenated monoterpenes (22.9%), sesquiterpene hydrocarbons (32.4%) and oxygenated sesquiterpenes (5.6%). The oil was dominated by β-pinene (15.1%), β-caryophyllene (12.6%), germacrene D (10.9%), camphor (7.3%), linalool (7.0%), sabinene (6.4%) and α-pinene (5.2%).

Aims: The aim of the research is to investigate the volatile constituents from C. zambesicus harvested in Lagos, Nigeria.

Study Design: Extraction of essential oil from the air-dried leaf samples of C. zambesicus and investigation of its chemical constituents.

Place and Duration of Study: Leaf samples of C. zambesicus were collected from Agbara, Lagos, on April 2011.

Methodology: Air-dried and pulverized leaves were hydrodistilled in a Clevenger-type apparatus to obtained pale yellow volatile oil whose chemical constituents was analyzed by GC and GC/MS.

Results: A total of sixty compounds were identified, amounting to 98.9%of the total oil contents. The major were compounds β-pinene (15.1%), β-caryophyllene (12.6%), germacrene D (10.9%) and camphor (7.3%). Variations in compositional pattern were observed between this result and the previous studies.

Conclusion: The literature about the C. zambesicus indicates a high variability in the chemical composition of the essential oils.

 

Open Access Original Research Article

Anatomical Changes during Rooting of Mangroves - Avicennia officinalis and Excoecaria agallocha

T. Govindan, K. Kathiresan

European Journal of Medicinal Plants, Page 1534-1542
DOI: 10.9734/EJMP/2014/11014

Mangrove forests continue to disappear all over the world due to a number of reasons. This is the study made to screen the anatomical and biochemical changes during the rooting process. Two important mangrove species have been examined based on their salt relationship natures: Avicennia officinalis subsp. australasica (salt excreting plant) and Excoecaria agallocha L (salt accumulating plant). The plants were treated with different root promoting hormones like IBA, IAA and NAA at different concentrations for three minutes each. After 45 days of the growth period root growth and anatomical changes were observed. The roots originated from the deeper zone of the secondary xylem after several anatomical variations in the hormone treated plants. This is the first trial which may help to determine the mass propagation of these commercial and medicinally important mangroves. 

 

Open Access Review Article

Therapeutic Properties of Zingiber officinale Roscoe: A Review

Hossein Asgar Pour, Reza Norouzzade, Mohammad Reza Heidari, Serdal Ogut, Hilmi Yaman, Serap Gokce

European Journal of Medicinal Plants, Page 1431-1446
DOI: 10.9734/EJMP/2014/11138

Aims: Ginger, a rhizome of Zingiber officinale Roscoe (Fam. Zingiberaceae), has been widely used as a spice to enhance the flavor of food and beverages and for medical purposes in various diseases.

Methodology: The review covers the databases and articles published between 2002-2013 via Medline and published papers on the Internet from Scientific Information Database, MagIran and Irandoc. Literature searches were performed to identify all the researches on ginger for treatment properties.

Results: The researchers conducted on ginger in medical field were about nausea and vomiting in pregnancy, contraceptive pills nausea, dysmenorrhea, motion sickness, cough, ventilator associated pneumonia, rheumatic diseases, antibacterial and antiviral effects, nausea and vomiting due to chemotherapy, spermatogenesis, anti-hyperlipidemia, anti-inflammatory, diabetes nephropathy and postoperative nausea and vomiting. Clinical trials about ginger were mostly to prevent and treat nausea and vomiting during pregnancy.

Conclusion: According to the published articles, ginger is an extraordinary herb and more detailed clinical trials using ginger are recommended for further studies in future.