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Open Access Original Research Article

Application of Pesticides in Rice-prawn (Crustaceans) Culture: Perception and Its Impacts

M. Nahid Hasan, H. M. Rakibul Islam, Y. Mahmud, K. K. U. Ahmed, S. Siddiquee

Annual Research & Review in Biology, Page 1219-1229
DOI: 10.9734/ARRB/2014/7125

The general purpose of this study was to evaluate farmers’ awareness towards the pesticides used in rice-prawn integrated culture technique. Randomly selected survey technique was applied through direct observations and personal interviews for this study. : Data were collected from five different upazillas viz. Fultola and Dumuria of Khulna, Mollahat, Fokirhat and Chitolmari of Bagerhat district which were situated in the south-west region in Bangladesh from January to March 2011. Randomly selected survey technique was applied to collect information from sample farmers which were chosen by consultation with local Agriculture Extension Officer and Fisheries Officer. A total of 75 (45 from Bagerhat and 30 from Khulna) sample farmers were asked to mention various information. Eight active ingredients of pesticides within 28 trade names were used to kill pest such as the stem borers, green leafhoppers and some of grasshoppers and gall midges infesting the rice farms. Pesticide frequency was varied between 1 and 3 sprays per crop season. A total of 94% respondents applied pesticides for controlling pests, 5% respondents used biological control and 1% respondent did not use any technique for pest management. The pesticide groups Organophosphorus and carbamate were used by 40% and 38% of the respondents respectively and another 15% farmers used pyrethroid in their rice crop during the winter period. Various groups of pesticides were used in order of 36% for Carbofuran, 17% for Chloropyriphos, 12% for Malathion, 11% for Diazinon, 7% for Cyhalotrin, 3% for Carbosulfan, 1% for Thiomax and 7% for Cypermethrin, respectively of the respondent farmers. No banned pesticides were identified from the respondents during this survey. It is suggested that pesticides regulation and effective implementation, increasing farmer’s awareness of effective pesticide use and expansion of IPM (Integrated Pest Management) practices can be helped towards sustainable integrated rice-prawn culture in the part of Bangladesh.

Open Access Original Research Article

Teratological Changes Generative Various of Wheat in a Weak Chloride Salinity

N. V. Terletskaya, N. A. Khailenko, L. K. Mamonov

Annual Research & Review in Biology, Page 1230-1240
DOI: 10.9734/ARRB/2014/6552

Aims: We examined the cytological response of generative cells in different varieties and types of wheat under salt stress to understand how the physiological state of plants is related to growth conditions and productivity.
Study Design: This study was conducted in the Laboratory of Cell engineering, Institute of Plant Biology and Biotechnology Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan from 2011-2012.
Methodology: The material for cytological studies served as the young ears are not released from the vagina of the upper leaves of various types of wheat subjected to the stage of stem elongation weak chloride salinity and without saline (control). Between 20 and 25 flowers on each ear were selected for cytological experiments. Samples were prepared and microsporocytes in the anthers were examined for at least 10 fields of view.
Results: In high-salt conditions (0.05% and 0.1% NaCl), viable fertile pollen grains were observed in all wheat species tested but teratological irregularities occurred during flower development and slowed both male and female gametophyte development.
Conclusion: The possibility of the evaluation of the physiological condition of the wheat plants in relation to the conditions of growth and productivity changes by the presence of teratology flowers.

Open Access Original Research Article

ROS and Antioxidant System of Triticum durum after Water Stress

Issaad Ghozlene, Djebar Mohammed-Reda, Rouabhi Rachid, Berrebbah Houria

Annual Research & Review in Biology, Page 1241-1249
DOI: 10.9734/ARRB/2014/5321

Aim: Water stress is the cause of many disturbances in plants. This work focuses on the effects of water stress on the roots and seeds of a durum wheat (Triticum durum) of the GTA variety.
Study Design: After germination, the plants were submitted to water stress, and many enzymatic tests are followed to evaluate the response of durum wheat plant to this stress.
Place and Duration of Study: Laboratory of cellular toxicology, department of biology, faculty of sciences, Annaba university, and laboratory of Cellular and Molecular Physiology of Plants of the Pierre and Marie Curie, Paris VI, France University.
Methodology: Seeding was carried out in plastic vessels. After 4 days of germination, the seeds of wheat were submitted to water stress by stopping irrigation and wheat samples were analyzed at 3rd, 5th, 7th and 9th day after interruption of watering. Controls were watered normally.
Germination took place at a Day temperature of 21ºC and 17-21ºC at Night with artificial lighting from 6 am to 10 pm.
Results: The results showed an increase in catalase activity (CAT), ascorbate peroxidase (APX) (specific enzymes o cellular detoxification system); this increase was less observed in the activity of guaiacol peroxidase (GPX).
On the other hand, as ever increase in the level of hydrogen peroxide (H2O2) in the roots was observed. This increase is proportional to the degree of induced stress. The observation under a fluorescence microscope was revealed that the produced hydrogen peroxide was localized generally in the cytoplasm and the cell wall.
Conclusion: It is clear and possible that water stress induced many plant disturbances and the increase of ROS production.

Open Access Original Research Article

Molecular Detection and Antimicrobial Activity of Enterolysin a Endopeptidase among Enterococcus faecalis Strains of Different Origins

Mitra Salehi, Zeinab Hatami

Annual Research & Review in Biology, Page 1250-1259
DOI: 10.9734/ARRB/2014/7216

Aims: The target of present study is to determine the frequency of occurrence of enterolysin A gene in Enterococcus faecalis strains from different sources and surveys about antibacterial effect of enl A gene positive strains.
Study Design: Enterolysin A is a class IV bacteriocin with broad spectrum of antimicrobial activity that is produced by some E. faecalis strains. However, research on the presence and antibacterial activity of this bacteriocin in different sources is very limited.
Place and Duration of Study: Islamic Azad University of North Tehran Branch Laboratory, between May 2011 and February 2012.
Methodology: In this study, the occurrence of enterolysin A structural gene in a target of 68 E. faecalis strains of three sources (animal feces, feed and surface water) was surveyed. Enterococcal strains were isolated from other feces Gram-positive and negative bacteria using Bile Aesculin Azide agar medium. After strains purification, E. faecalis bacteria were identified and the occurrence of enterolysin A gene was evaluated by using PCR method. The antimicrobial spectrum of enl A gene positive E. faecalis strains was assayed by deferred antagonism assay method on the some gram-positive and negative pathogen bacteria.
Results: Based on our results, 20 strains (29.4%) possessed enterolysin A structural gene. Different frequencies of the enterolysin A gene occurrence were detected in strains according to thebacterial origins; the strains from silage and lovebirds showed the highest frequency of enterolysin A gene presence. These gene-positive strains inhibited the growth of indicator bacteria such as clinical strain of Pseudomonas aeruginosa, Listeria monocytogenes, Bacillus cereus and Salmonella enterica PTCC1709.
Conclusion: Enterolysin A structural gene similar to the other enterocin genes present in enterococci of different origins. Moreover, efficiency of enterolysin A against pathogenic bacteria makes it a suitable candidate for their application in veterinary medicine, alternative antimicrobial compounds or bio-preservatives in food or feed.

Open Access Original Research Article

Levels of Selected Heavy Metals in Fresh Meat from Cattle, Sheep, Chicken and Camel Produced in Algeria

Bendeddouche Badis, Zellagui Rachid, Bendeddouche Esma

Annual Research & Review in Biology, Page 1260-1267
DOI: 10.9734/ARRB/2014/7430

Aims: Levels of selected heavy metals iron, copper, zinc, lead, cadmium and mercury were determined in fresh meat from cattle, sheep, chicken and camel produced in Algeria.
Methodology: We are using atomic absorption spectrophotometry in some different samples of beef (n=120), sheep (n=120), chicken (n=120) and camel (n=120) of fresh meat collected in two areas north and south from Algeria.
Results: The order of the levels of the trace elements obtained was iron >zinc >copper> lead >cadmium >mercury. The highest concentration of iron and lead were found in the chicken meat (246.83µg/g, 8.80µg/g respectively) while camel’s meat maintained the lowest values of most studied metals except values of lead (3.21µg/g) and zinc (4.17µg/g) in southern area.
Samples from the north area are more contaminated due to massive industrialization and agricultural practices.
Conclusion: The concentrations of all essential elements in the selected products were high and often exceeded legal limits set by health authorities.

Open Access Original Research Article

Responses of Different Maturity Type Wheat’s Cultivar to Planting Date at Moderate Regions in Iran

Rahmani Aabdolah, Ahmad Jafarnezhad, Mohammad Armin

Annual Research & Review in Biology, Page 1268-1277
DOI: 10.9734/ARRB/2014/5956

Aims: Investigation of responses of different maturity type wheat’s cultivar to planting date.
Study Design: A split-plot arrangement within a randomized complete block design with 4 replication.
Place and Duration of Study: This study was carried out from 2007-2008 in Neyshabur agricultural research station.
Methodology: Theeffect of planting date and maturity type wheat’s cultivar on yield components containing spike number at square meter, spike number per spike, seed number at spikelet, seed number at spike, 1000 seed weight, economic yield and biological yield were assessed. Planting date (11 oct, 15, nov, 30nov) as a main plot andmaturity type wheat’s cultivar (Alamot and Mv17 9(winter type) Toos and Alvand (intermediate type) Marvedasht and Pishtaz (spring type) as sub plot.
Results: The result showed that the number of tillers, number of spike, number of grains spike and biological yield was not affected by the planting date. The maximum and minimum economic yield was obtained on November 30th and October 11th, respectively. Yield components were not affected by maturity type. Wheat cultivar had a different response to planting date. With a delay in planting date, winter type had more of a decrease in economic yield than spring and intermediate types. Decreases of spike number were the main reason for the decreasing of economic yield in the winter type cultivar.
Conclusion: Overall, the most suitable planting date for the winter types was in the middle of October and for spring types in the middle of NovemberIn temperate regions, spring type had more economic yield than the winter and intermediate types.

Open Access Original Research Article

Toxicological Impact of Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on Some Hormonal Profiles and Hematological Parameters in Goats

Azza M. Mohamed, A. O. Hegab, Jehad M. Yousef, Manal E. A. El H alwagy

Annual Research & Review in Biology, Page 1278-1289
DOI: 10.9734/ARRB/2014/6614

Female Baladi goats were used to investigate the toxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on some serum hormones and blood features.
Animals were divided into two groups, group 1: served as control, group 2: animals were orally administered with three repeated doses (0.23µg/Kg body weight) of TCDD with 2 days interval between dosing.
Results revealed that exposure to TCDD induced reduction in serum estradiol, progesterone and prolactin levels and elevation in glucocorticoid hormone cortisol throughout the different studied periods (48h, 96h and 16 days commenced the last intoxicated dose). The adverse impact of TCDD on goat reproductive hormones was confirmed by histopatholgical observations on their uteri and ovaries after 16 days commenced the last intoxicated dose. Intoxication of goats with TCDD showed also marked decreases in hemoglobin (Hb) concentration, red blood cell count (RBC), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentrations (MCHC) compared with normal healthy group. Pronounced decreases in total white blood cells (WBC) count as well as in its differential percentages namely lymphocytes, monocytes and eosinophils were also noticed in intoxicated animals compared with normal ones, while the percentage of neutrophils showed significant increase.
In conclusion, the results of this study indicated that oral exposure of female goats to repeated doses of TCDD caused endocrine disruption which may lead to adverse impact on their reproductive performance. Moreover, toxicity of TCDD induced immunosuppressive effect and anemia as indicated by its deleterious action on different hematological parameters.

Open Access Original Research Article

Potentiality of Garlic and/or Green Tea Aqueous Extracts in Attenuating Pesticides Induced Toxicity in Albino Rats

Widad M. Al-Bishri, Jehad M. Yousef, Gamila A. M. Kottb, Azza M. Mohamed, Manal E. A. Elhalwagy

Annual Research & Review in Biology, Page 1290-1306
DOI: 10.9734/ARRB/2014/6733

Aim: The present work aimed to evaluate the effect of each of green tea (GT) and garlic (Ga) aqueous extract and their combination on pesticide Duracine induced changes in plasma levels of some indices of oxidative stress; and in protein electrophoretic patterns, in albino rats.
Study Design: Forty rats were divided into 8 groups 5rats each and treated orally for 14 days as follows: G1 (control);-G 2 (200mg GT per animal);- G 3 (1ml of 50% of garlic):- G4 (200mg green tea per animal and 1ml of 50% of garlic); G 5 20mg /Kg bwt [equivelant 1/14 LD50 of Duracine] ,G6 (green tea and Duracine):- G7 (garlic and Duracine):- G8 (green tea, garlic and Duracine). Plasma activities of acetylcholinesterase (AChE), glutathione-S-transferase (GST) and glutathione reductase (GR) activities and levels of malondialdehyde (MDA) and total reduced glutathione (GSH) were analyzed using standard methods.
Results: Duracine intoxication induced significant decrease in plasma AChE, GST and GR. It elevated plasma MDA, decreased plasma total GSH, as well as, changes in plasma protein electrophoretic pattern. Individual supplementation with GT induced slight improvement in AchE, GSH and MDA. On the other hand, supplementation with aqueous extract of garlic induced significant (P<0.05) enhancement in the level of GSH in the intoxicated animals. Combined supplementation with GT+Ga produced significant (P<0.05) counteracting effect in MDA,GSH,GST and GR, as well as ,counteracting changes in plasma protein pattern was not remarkable this may be due to plasma protein half life.
Conclusion: It seems that, combined supplementation of green tea and garlic improve the oxidative stress parameters but needa more time to improve other toxicity markers.

Open Access Original Research Article

Application Potential of Liposomal Delivery Systems Prepared by Lipids Extracted from E. coli Cultures

Mohammad Kargar, Eskandar Moghimipour, Zahra Ramezani, Somayeh Handali

Annual Research & Review in Biology, Page 1319-1329
DOI: 10.9734/ARRB/2014/7611

Aims: Liposomes are spherical vesicles composed of concentric phospholipid bilayers that can entrap hydrophilic, hydrophobic and amphiphilic drugs. Liposomes can be prepared from natural phospholipids, synthetic lipids or bacterial lipids. Regarding to the easy access to microorganisms in all year round, being economic and possibly growing in various substrates, bacterial lipids can be suitable candidates for preparation of liposomes.
Objective: The aim of the present study was to formulate and evaluate liposomal vesicles prepared by lipid extracted from E. coli and loaded with methylene blue as drug model.
Material and Methods: The lipids were extracted from the bacteria E.coli and analyzed by High Performance Thin-Layer Chromatography (HPTLC). Liposomes were prepared using film method and then characterized by Differential Scanning Calorimetry (DSC), and their particle sizes were measured. The release of methylene blue was determined using dialysis membrane method.
Results: HPTLC analysis of the extracted lipids indicated that the glycerol ether was the major lipid with more than 70 percent probability. Results of particle size determination showed a mean size of 338 nm. The DSC curve of liposomes without methylene blue was different from methylene blue containing liposomes that indicated the possible interaction methylene blue with lipids during the preparation of liposomes. Encapsulation efficiency was 53.33±2.88% and there was 97.54%±0.00 release after 24 h.
Conclusion: The results of this study may indicate the possible use bacterial lipids in preparation of nano-drug delivery derived system.

Open Access Original Research Article

Extraction of Phenolic Compounds and Tannins from Pistachio By-products

A. Mokhtarpour, A. A. Naserian, R. Valizadeh, M. Danesh Mesgaran, F. Pourmollae

Annual Research & Review in Biology, Page 1330-1338
DOI: 10.9734/ARRB/2014/7793

Aims: This study was conducted to evaluate the effects of solvent, particle size, extraction time and ultrasound on extraction and quantification of phenolic compounds and tannins in pistachio by-products (PB).
Study Design: Factorial experiment based on completely randomized design.
Methodology: Four solvents (70% aqueous acetone, 50% aqueous methanol, 50% aqueous ethanol and water), 2 particle size (fine vs coarse) and 2 extraction time (12 vs 24h) were used to extract total phenolics (TP) and total tannins (TT) of sun-dried PB (93.5% DM). Folin-Ciocalteu reagent was used for phenolics and tannins quantification. In another experiment, ultrasound-assisted extraction (UAE) was used for extracting phenolic compounds.
Results: Using 70% aqueous acetone resulted in more TP (13.86% of DM as tannic acid equivalent) compared to other solvents and the lowest TP content was measured in water (9.87%). Particle size and time of extraction had no effect on TP content. Tannin concentration were not affected by particle size but decreased by increasing time from 12 to 24h (7.34 vs 6.81%). Higher tannin was extracted by 50% aqueous ethanol compared to aqueous methanol and/or water (7.82%). However, no differences were observed between 70% aqueous acetone and 50% aqueous ethanol and/or methanol. The interactions between main effects were not statistically significant. In another experiment, TP and TT were extracted by ultrasound-assisted extraction (UAE) and results were compared to 12h extraction (without ultrasonic). No difference was observed between two methods in terms of TP and TT.
Conclusion: It can be concluded that using 70% aqueous acetone and 50% aqueous ethanol are more convenient solvent for extraction of phenolics and tannins in PB, respectively.

Open Access Original Research Article

Comparing Different Cultivars of Iranian Pomegranate by the Amount of Epicatechin and Epigallocatechin Gallate

Forogh Mortazaeinezhad, Kamran Safavi, Abas Abed Esfahani, Maryam Evaj Shirvani

Annual Research & Review in Biology, Page 1339-1345
DOI: 10.9734/ARRB/2014/6046

Aims: The pomegranate, Punica granatum, is cultivated in tropical and subtropical region. Pomegranates contain a polyphenols such as gallic acid, ellagitannins, gallotannins, chlorogenic acid, caffeic acid, ferulic acid, coumaric acids, and catechin and anthocyanins. The term catechin is also commonly used to refer to the related family of flavonoids and the subgroup flavan-3-ols. In this study we want to compare the amount of catechin in different cultivars of Iranian pomegranate.
Place and Duration of Study: Department of Horticulture and Department of Food science and technology, Khorasgan (Isfahan) Branch, Islamic Azad University, Isfahan, Iran, between march 2010 and November 2012.
Methodology: We gathered the fruit of Iranian pomegranate cultivars in order to make them dry in freeze dryer (w028, Germany). All of the freeze dryer samples were grained and became a soft powder before analysis. 0.5 g sample, mixed with 25 ml of 80 percent ethanol-water solution, was kept in an ultrasonic bath to extract catechins (M. G. Miguel, 2010). Experiments showed that 80 percent of methanol -water gives the best result and this liquid is the best type. Five minutes of putting in the ultrasonic bath is equivalent to 1 hour of mechanical shaker. 2 ml of high Centrifuge for 5 minutes in a 14000 rpm round by the 0.45ml pourfilter and 20 ml of HPLC to liquid chromatography were injected (J. Dai, 2010). The liquid chromatography was equipped to 1050 HP pomp, 1100HP thermostat, injector750 Rheodyne and fluorescence remover HP 1100. Returnable faze was used in 30 degree centigrade temperature and in C18 column. 100*4/6mm 2i.d;3µm with pre column of c18 Altima were equipped. Washing the isocratic by liquid phase of 9% of acetonitrile in the 2% of Acid citric in a 11 m per minutes separation with the insulator in a EX=280nm of catechin, they were determined by value of catechins aggregation of plotting (µg/ml) with calibration graph were done and the calibration with the stock solution in the 40% methanol got ready.
Results: Results also showed that the highest amounts of Epigallocatechin gallate were existed in “Malas Saveh” and the lowest amounts of epicatechin were existed in “Alak Parand Saveh”.
Conclusion: Our data showed that Epicatechin and Epigallocatechin gallate are the most abundant catechin in pomegranate and they are a potent antioxidant that may have therapeutic application.

Open Access Original Research Article

The Toxicity of Gold, Silver, and Zinc Oxide Nanoparticles on LDH Enzyme in Male Mice

Masoud Negahdary, Marziyeh Ajdary

Annual Research & Review in Biology, Page 1346-1352
DOI: 10.9734/ARRB/2014/5370

Aims: Nanoparticles have the potential to be used in medical imaging, disease diagnosis, cancer treatment and other procedures. These nanoparticles accumulate in the body tissues and result in oxidative stress with the generation of reactive oxygen species. This study investigates the effects of gold, silver, and zinc oxide nanoparticles on the LDH enzyme in male mice.
Methodology: Adult Wistar strain albino mice (60) weighing 20-38 g were used for this study. The mice were randomly assigned to 3 classes in a way that in each class there were four groups of which one group was control and the other three groups were fed by zinc-oxide nanoparticles (ZnONPs), gold nanoparticles (AuNPs), and silver nanoparticles (AgNPs) at 100, 50, 25 ppm concentrations, respectively, for 15 days and the heart blood was taken to measure LDH enzyme activity at the end of treatment.
Results: There was a significant difference (p<0.05) in the LDH level with use of a moderate concentration of gold nanoparticles (50mg/kg) and in moderate and low concentrations of silver nanoparticles (50 and 25mg/kg) and in all concentration of zinc oxide nanoparticles (100, 50, and 25mg/kg) as compared to the control group.
Conclusion: Our results show that a moderate concentration in each of the three nanoparticles leads to an increase in LDH enzyme activity as compared with the control group.

Open Access Review Article

Role of Platelets Rich Plasma in Management of Osteoporotic Fractures

Ajai Singh, Sabir Ali, Abbas Ali Mahdi, Rajeshwar Nath Srivastava

Annual Research & Review in Biology, Page 1187-1210
DOI: 10.9734/ARRB/2014/6130

Management of osteoporotic fracture is challenging. In most clinical settings, skeletal regenerations are biologically optimized, but still many patients continue to experience delayed or impaired healing. Methods to enhance these healing processes, are needed to decrease patient’s agony, so that they can return to their work and regain their socioeconomic status in the community. Till this time, autologous bone grafting remain the standard procedure against which all new technologies are compared and analyzed.The success rate of union even after these grafts varies between 80-85% which further becomes decreased in case of repeated bone graft surgeries with donor site morbidities. Considering the concept that the healing of fracture started as soon as the formation of fracture clot, several investigators have suggested that degranulation of platelets at fracture clot elaborates the bioactive component, that aided the healing process. Because autologous platelet rich plasma products are safe and easy to prepare and administer, in this review, we reviewed the role of bioactive component released by activated platelet rich plasma in the fracture healing process and hypothesized that by combining the advantages of autologous bone grafts with autologous platelets concentrate, better and prompt results in orthopedic trauma managements can be obtained. We also observe that the use of these bioactive factors to enhance skeletal repair/healing represents the future of skeletal trauma management.

Open Access Review Article

Waist Circumference and Metabolic Syndrome: A Review

Abdoljalal Marjani

Annual Research & Review in Biology, Page 1211-1218
DOI: 10.9734/ARRB/2014/6811

It is known that there is an increasing in prevalence of metabolic syndrome worldwide. The most investigated component of metabolic syndrome is waist circumference. The World Health Organization reported that waist circumference is the easiest and most efficient anthropometric index to be used in many studies. Waist circumference gives information on the general and abdominal obesities. Many different studies on waist circumference have been exhibited that it is a significant component of metabolic syndrome which is in relation to various diseases and risk factors for various ethnicities. It has been shown that waist circumference is a better predictor than body mass index in metabolic syndrome detection. The purpose of present review is to converse waist circumference variations in metabolic syndrome.

Open Access Review Article

Serotypes and Genotypes of the Hepatitis B Virus in Latin America

Rosa María Ribas-Aparicio, Hilda-Alicia Valdez-Salazar, Gerardo Aparicio-Ozores, Martha-Eugenia Ruiz-Tachiquín

Annual Research & Review in Biology, Page 1307-1318
DOI: 10.9734/ARRB/2014/7901

The World Health Organization has estimated that 2 billion persons are infected with the hepatitis B virus (HBV) with 360 million persons chronically affected. Worldwide, HBV is the causal agent of cirrhosis (30%) and hepatocellular carcinoma (50%). Methods of transmission for HBV are prenatal, percutaneous, and sexual.
HBV genotypes, subgenotypes, and subtypes represent genetically stable viral populations that share a separate evolutionary history. Additional instable changes arising from mutations and mutant selection have been observed; these viral subpopulations are HBV variants with medical treatment relevance. Expression of the subtype renders antigenically diverse strains. The same region contains an unknown number of epitopes that define the so-called “a” determinant. Thus, we have two mutually exclusive determinants (d/y, w/r) with four variants (w1-w4 and the expression of a third, q). The difference in 8% of the HBV genome produces different viral groups. Currently, there are ten of these groups (genotypes) classified from A to J, with different geographic distributions. Multiethnic populations present several genotypes and variability is increasing because there are reports of subgenotypes and recombinant intergenotypes, which render the design of effective drugs to combat and eliminate this very difficult virus.