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Antonio Figueira - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of in vitro and in vivo effects of semipurified proteinase inhibitors from Theobroma seeds on midgut protease activity of Lepidopteran pest insects.
Archives of insect biochemistry and physiology, 2012Co-Authors: Luis Paulillo, Alexandre Magno Sebbenn, Maria Tereza Vitral De Carvalho Derbyshire, Aristóteles Góes-neto, Marco Brotto, Antonio FigueiraAbstract:We have characterized in vitro and in vivo effects of trypsin inhibitors from Theobroma seeds on the activity of trypsin- and chymotrypsin-like proteins from Lepidopteran pest insects. The action of semipurified trypsin inhibitors from Theobroma was evaluated by the inhibition of bovine trypsin and chymotrypsin activities determined by the hydrolysis of N-Benzoyl-DL-Arginine-p-Nitroanilide (BAPA) and N-Succinyl-Ala-Ala-Pho-Phe p-Nitroanilide (S-(Ala)2ProPhe-pNA). Proteinase inhibitor activities from Theobroma cacao and T. obovatum seeds were the most effective in inhibiting trypsin-like proteins, whereas those from T. obovatum and T. sylvestre were the most efficient against chymotrypsin-like proteins. All larvae midgut extracts showed trypsin-like proteolytic activities, and the putative trypsin inhibitors from Theobroma seeds significantly inhibited purified bovine trypsin. With respect to the influence of Theobroma trypsin inhibitors on intact insects, the inclusion of T. cacao extracts in artificial diets of velvet bean caterpillars (Anticarsia gemmatalis) and sugarcane borer (Diatraea saccharalis) produced a significant increase in the percentage of adult deformation, which is directly related to both the survival rate of the insects and oviposition.
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Theobroma
Wild Crop Relatives: Genomic and Breeding Resources, 2011Co-Authors: Dapeng Zhang, Philippe Lachenaud, Antonio Figueira, Lambert Motilal, Lyndel W. MeinhardtAbstract:Cacao (Theobroma cacao L.) is a neotropical tree species with significant economic importance. The availability of diverse cacao germplasm is the foundation for breeding new varieties for resistance to diseases and pests, for environmental adaptation, and for superior processing quality. Cacao was domesticated in Mesoamerica several thousand years ago, but the center of diversity is in the Amazon basin in South America. There has been a significant progress in the understanding of the wild populations and related species of T. cacao in the last decade, owing to the rapid technology advance and the dedicated research programs to the conservation and improvement of cacao. This chapter examines the events that have led to the current status of conservation and utilization of wild populations and the related species of cacao. (Résumé d'auteur
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Evaluating Theobroma grandiflorum for comparative genomic studies with Theobroma cacao
Tree Genetics & Genomes, 2010Co-Authors: David N. Kuhn, Juan Carlos Motamayor, Antonio Figueira, Uilson Vanderlei Lopes, Alan W. Meerow, Kathleen Cariaga, Barbie Freeman, Donald Livingstone, Raymond J. SchnellAbstract:The seeds of Theobroma cacao (cacao) are the source of cocoa, the raw material for the multi-billion dollar chocolate industry. Cacao’s two most important traits are its unique seed storage triglyceride (cocoa butter) and the flavor of its fermented beans (chocolate). The genome of T. cacao is being sequenced, and to expand the utility of the genome sequence to the improvement of cacao, we are evaluating Theobroma grandiflorum, the closest economically important species of Theobroma for its potential use in a comparative genomic study. T. grandiflorum differs from cacao in important agronomic traits such as flavor of the fermented beans, disease resistance to witches’ broom and abscission of mature fruits. By comparing genomic sequences and analyzing viable inter-specific hybrids, we hope to identify the key genes that regulate cacao’s most important traits. We have investigated the utility in T. grandiflorum of three types of markers (microsatellite markers, single-strand conformational polymorphism markers and single nucleotide polymorphism (SNP) markers) developed in cacao. Through sequencing of amplicons of 12 diverse individuals of both cacao and T. grandiflorum, we have identified new intra- and inter-specific SNPs. Two markers which had no overlap of alleles between the species were used to genotype putative inter-specific hybrid seedlings. Sequence conservation was significant and species-specific differences numerous enough to suggest that comparative genomics of T. grandiflorum and T. cacao will be useful in elucidating the genetic differences that lead to a variety of important agronomic trait differences.
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Microsatellite loci transferability from Theobroma cacao to Theobroma grandiflorum
Molecular Ecology Notes, 2006Co-Authors: Rafael Moysés Alves, Alexandre Magno Sebbenn, Angela S. Artero, Antonio FigueiraAbstract:Theobroma grandiflorum (cupuassu) is an important fruit tree native to the Brazilian Amazon. Forty-eight microsatellite loci developed for the congener Theobroma cacao were tested in cupuassu, and 29 (60.4%) produced robust alleles. The analyses of 216 cupuassu accessions using the 21 polymorphic microsatellite loci revealed a total of 113 alleles. The number of alleles per polymorphic locus ranged from two to 11, with an average of 5.38 alleles per locus. The average observed heterozygosity was 0.343, while the mean expected heterozygosity was 0.614. The successful transferability of T. cacao microsatellite primers to cupuassu was consistent with currently accepted phylogeny.
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Phylogenetic analysis of Theobroma (Sterculiaceae) based on Kunitz-like trypsin inhibitor sequences
Plant Systematics and Evolution, 2004Co-Authors: C. R. Sousa Silva, Antonio FigueiraAbstract:Trypsin inhibitor gene sequences were used to investigate the phylogenetic relationships among Theobroma and Herrania species, considered as sister-groups, with particular interest on the monophyly and infra-generic relationships of Theobroma. The presumed amino acid sequences of 23 analyzed samples, from 11 Theobroma and three Herrania species, comprising all sections from both genera, demonstrated a high similarity with a previously characterized T. cacao Kunitz trypsin inhibitor. The trypsin inhibitor gene accumulated mutations at faster rate than prior analyzed nuclear or chloroplastic genes. None of the sequences presented introns. The phylogeny of the trypsin inhibitor sequences was congruent with the phylogenetic hypotheses of the Theobroma and Herrania species based on morphology. The monophyly of Theobroma was not strongly supported, corroborating previously described absence of obvious synapomorphies for Theobroma. The species grouped consistently according to genus and section. The monophyly of all Theobroma sections was supported, except for section Glossopetalum, which was paraphyletic to section Andropetalum. Evidences sustain that T. mammosum may be included into section Glossopetalum. The potential use of trypsin inhibitor gene sequences in phylogenetic studies of Theobroma was demonstrated.
C C Mullergoymann - One of the best experts on this subject based on the ideXlab platform.
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further characterization of Theobroma oil beeswax admixtures as lipid matrices for improved drug delivery systems
European Journal of Pharmaceutics and Biopharmaceutics, 2006Co-Authors: A A Attama, B C Schicke, C C MullergoymannAbstract:Abstract There is an increasing interest in lipid based drug delivery systems due to factors such as better characterization of lipidic excipients and formulation versatility and the choice of different drug delivery systems. It is important to know the thermal characteristics, crystal habit, texture, and appearance of a new lipid matrix when determining its suitability for use in certain pharmaceutical application. It is line with this that this research was embarked upon to characterize mixtures of beeswax and Theobroma oil with a view to applying their admixtures in drug delivery systems such as solid lipid nanoparticles and nanostructured lipid carriers. Admixtures of Theobroma oil and beeswax were prepared to contain 25% w/w, 50% w/w, and 75% w/w of Theobroma oil. The admixtures were analyzed by differential scanning calorimetry (DSC), small angle X-ray diffraction (SAXD), wide angle X-ray diffraction (WAXD), and isothermal heat conduction microcalorimetry (IMC). The melting behavior and microstructures of the lipid admixtures were monitored by polarized light microscopy (PLM). Transmission electron microscopy (TEM) was used to study the internal structures of the lipid bases. DSC traces indicated that the higher melting peaks were roughly constant for the different admixtures, but lower melting peaks significantly increased (p
A A Attama - One of the best experts on this subject based on the ideXlab platform.
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Solid lipid nanodispersions containing mixed lipid core and a polar heterolipid: characterization.
European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V, 2006Co-Authors: A A Attama, B C Schicke, T. Paepenmüller, Christel C. Müller-goymannAbstract:Abstract This paper describes the characterization of solid lipid nanodispersions (SLN) prepared with a 1:1 mixture of Theobroma oil and goat fat as the main lipid matrix and Phospholipon 90G ® (P90G) as a stabilizer heterolipid, using polysorbate 80 as the mobile surfactant, with a view to applying the SLN in drug delivery. The 1:1 lipid mixture and P90G constituting the lipid matrix was first homogeneously prepared by fusion. Thereafter, the SLN were formulated with a gradient of polysorbate 80 and constant lipid matrix concentration by melt-high pressure homogenisation. The SLN were characterized by time-resolved particle size analysis, zeta potential and osmotic pressure measurements, differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). Transmission electron microscopy (TEM) and isothermal heat conduction microcalorimetry (IMC) which monitors the in situ crystallization were also carried out on the SLN containing P90G and 1.0 % w/w of polysorbate 80. The results obtained in these studies were compared with SLN prepared with Theobroma oil with and without phospholipid. Particle size analysis of SLN indicated reduction in size with increase in concentration of mobile surfactant and was in the lower nanometer range after 3 months except SLN prepared without P90G or polysorbate 80. The lipid nanoparticles had negative potentials after 3 months. WAXD and DSC studies revealed low crystalline SLN after 3 months of storage except in WAXD of SLN formulated with 1.0 % w/w polysorbate 80. TEM micrograph of the SLN containing 1.0 % w/w polysorbate 80 revealed discrete particles whose sizes were in consonance with the static light scattering measurement. In situ crystallization studies in IMC revealed delayed crystallization of the SLN with 1.0 % w/w polysorbate 80. Results indicate lipid mixtures produced SLN with lower crystallinity and higher particle sizes compared with SLN prepared with Theobroma oil alone with or without P90G, and would lead to higher drug incorporation efficiency when used in formulation of actives. Mixtures of Theobroma oil and goat fat would be suitable for the preparation of nanostructured lipid carriers. SLN of Theobroma oil containing phospholipid could prove to be a good ocular or parenteral drug delivery system considering the low particle size, particle size stability and in vivo tolerability of the component lipids. SLN prepared with lipid admixture, which had higher increase in d 90% on storage are suitable for preparation of topical and transdermal products.
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further characterization of Theobroma oil beeswax admixtures as lipid matrices for improved drug delivery systems
European Journal of Pharmaceutics and Biopharmaceutics, 2006Co-Authors: A A Attama, B C Schicke, C C MullergoymannAbstract:Abstract There is an increasing interest in lipid based drug delivery systems due to factors such as better characterization of lipidic excipients and formulation versatility and the choice of different drug delivery systems. It is important to know the thermal characteristics, crystal habit, texture, and appearance of a new lipid matrix when determining its suitability for use in certain pharmaceutical application. It is line with this that this research was embarked upon to characterize mixtures of beeswax and Theobroma oil with a view to applying their admixtures in drug delivery systems such as solid lipid nanoparticles and nanostructured lipid carriers. Admixtures of Theobroma oil and beeswax were prepared to contain 25% w/w, 50% w/w, and 75% w/w of Theobroma oil. The admixtures were analyzed by differential scanning calorimetry (DSC), small angle X-ray diffraction (SAXD), wide angle X-ray diffraction (WAXD), and isothermal heat conduction microcalorimetry (IMC). The melting behavior and microstructures of the lipid admixtures were monitored by polarized light microscopy (PLM). Transmission electron microscopy (TEM) was used to study the internal structures of the lipid bases. DSC traces indicated that the higher melting peaks were roughly constant for the different admixtures, but lower melting peaks significantly increased (p
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Further characterization of Theobroma oil–beeswax admixtures as lipid matrices for improved drug delivery systems
European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V, 2006Co-Authors: A A Attama, B C Schicke, Christel C. Müller-goymannAbstract:Abstract There is an increasing interest in lipid based drug delivery systems due to factors such as better characterization of lipidic excipients and formulation versatility and the choice of different drug delivery systems. It is important to know the thermal characteristics, crystal habit, texture, and appearance of a new lipid matrix when determining its suitability for use in certain pharmaceutical application. It is line with this that this research was embarked upon to characterize mixtures of beeswax and Theobroma oil with a view to applying their admixtures in drug delivery systems such as solid lipid nanoparticles and nanostructured lipid carriers. Admixtures of Theobroma oil and beeswax were prepared to contain 25% w/w, 50% w/w, and 75% w/w of Theobroma oil. The admixtures were analyzed by differential scanning calorimetry (DSC), small angle X-ray diffraction (SAXD), wide angle X-ray diffraction (WAXD), and isothermal heat conduction microcalorimetry (IMC). The melting behavior and microstructures of the lipid admixtures were monitored by polarized light microscopy (PLM). Transmission electron microscopy (TEM) was used to study the internal structures of the lipid bases. DSC traces indicated that the higher melting peaks were roughly constant for the different admixtures, but lower melting peaks significantly increased (p
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Melt Extrusion Bioadhesive Drug Delivery : A Care Of Diclofenac Contained In Carbopol 940 Matrices
Indian Journal of Pharmaceutical Sciences, 2005Co-Authors: A A Attama, Petra O NnamaniAbstract:Carbopol 940 and Theobroma oil were used to formulate melt extrusion bioadhesive tablets of diclofenac. Different batches of the tablets were formulated using different quantities of Carbopol 940 granules containing diclofenac and Theobroma oil in a plastic mould by pour moulding. The bioadhesion of the tablets were measured by determining the bioadhesive strength generated when the tablet interacted with the mucus on everted hog jejunum on a tensiometer adapted for that purpose. The tablets were evaluated using weight uniformity, resistance to rupture and liquefaction time. Release of diclofenac from the tablets was studied in simulated intestinal fluid (Ph 7.2) without pancreatin. The tablets had low liquefaction times and were highly bioadhesive. Result of the study indicated that Theobroma oil could be used to formulate melt extrusion bioadhesive tablets of diclofenac. All the tablets evaluated conformed to pharmacopoeial specifications.
Gianni Sacchetti - One of the best experts on this subject based on the ideXlab platform.
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Lipid composition of wild ecuadorian Theobroma subincanum Mart. seeds and comparison with two varieties of Theobroma cacao L.
Journal of agricultural and food chemistry, 2000Co-Authors: Renato Bruni, Ercolina Bianchini, Lisa Bettarello, Gianni SacchettiAbstract:The present work analyzes the lipid fraction from seeds of wild Ecuadorian Theobroma subincanum and selected commercial varieties of Theobroma cacao from Mexico (var. Criollo) and Ecuador (var. Arriba). The lipid fraction was obtained from the seeds through supercritical fluid extraction and analysis performed by preparatory thin-layer chromatography followed by gas chromatography. The results revealed that in T. subincanum the triglycerides contain fatty acids with longer chains. The melting point and peroxide and saponifiable numbers were determined for each Theobroma sample. The results lead to the conclusion that T. subincanum would produce a poorer quality butter than T. cacao. Nevertheless, the results do point toward a significant commercial use of T. subincanum for low-profile products.
Yuli Yetri - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Cuprum (Cu) Layer by Electrodeposition Method with Theobroma cacao Peels as Corrosion Protector of Steel
International Journal on Advanced Science Engineering and Information Technology, 2018Co-Authors: Nurry Putri Tissos, Yuli Yetri, Dahyunir DahlanAbstract:Corrosion is a natural phenomenon that can not be prevented the process of occurrence, but the timing may be delayed. Various efforts have been made in reducing the impact of losses caused by corrosion. One such effort is to coat the metal surface with a thin layer. As well as other efforts is to use an inhibitor. Efforts have been made to reduce the impact of corrosion loss by synergizing surface coating and using of inhibitors. Deposition of a thin layer of Cu using electrodeposition method with 0.05 M CuSO 4 .5H 2 O electrolyte solution and addition of inhibitor of Theobroma cacao peels extract. In this research has been done some variation that is variation of electrodeposition time and variation of concentration of inhibitor of Theobroma cacao peels extract. Scanning Electron Microscope (SEM) characterization shows electrodeposition of a thin layer of Cu for three minutes, a voltage of three volts, and with the addition of an inhibitor of Theobroma cacao peels extract 1% producing a smooth, homogeneous and more uniform surface morphology. Based on the result of characterization with X-Ray Diffraction (XRD) obtained steel surface at electrodeposition with the addition of an inhibitor of Theobroma cacao peels extract, there are sharper peaks of Cu. Based on the corrosion test obtained value of Inhibition Efficiency inhibitor of Theobroma cacao peels extract amounted to 69.4% with the addition of 1%, and 81.9% with the addition of inhibitor 1.5%. Based on this, inhibitor of Theobroma cacao peels extract can reduce the attack rate of corrosion on the steel surface in corrosive media HCl 1N.
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Theobroma Cacao Peels Extract as the Eco-Friendly Corrosion Inhibitor for Mild Steel
2018Co-Authors: Yuli Yetri, Emriadi, Gunawarman, Novesar JamarunAbstract:ABSTRACT Corrosion control for metals is importance of technical, economical, environmental, and aesthetical . The use of corrosion inhibitors from natural product is one of the best ways to slow the rate of corrosion of metals and alloys. The use of extract inhibitors from natural product is the best alternative, because it is non-toxic, environmentally friendly, biodegradable, does not contain heavy metals, easy to obtain, inexpensive, and available in large quantities. The organic compounds contained in the extracts of natural product such as tannins, amino acids, phenolics, and alkaloids contain hetero-atomic groups which can inhibit corrosion rate and are interesting to study. With the development of science and technology, many methods are used to protect the corrosion, such as, electroplating, coating, and organic inhibitor show real promise such as Theobroma cacao peels extract. Although substantial research has been devoted to corrosion inhibition by plant extracts, reports on the detailed mechanisms of the adsorption process and identification of the active ingredient are still scarce. The addition of polar extract of cacao into a solution of HCl 1.5 mol/L is very effective to reduce the attack surface corrosion on mild steel, and can maintain its mechanical properties.The present paper consciously restricts itself mainly to plant materials Theobroma cacao peels extract as green corrosion inhibitors. Keywords: Theobroma cacao, Corrosion inhibitor, Plant product, Coating
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Correlation between inhibition efficiency and adsorption occurs on thesteel surface using corrosion inhibitor of peels cacao extract(Theobroma cacao) in HCl media
2016Co-Authors: Yuli Yetri, Emriadi, Novesar Jamarun, GunawarmanAbstract:Abstract With the increasing of Theobroma cacao plantation, cacao peels waste would also increase. Cocoa fruit skin will damage the environment if not done processing. The peels of cacao contains of organic compound that can be used as corrosion inhibitor. This compound has advantage in being non toxic and biodegradable. Essential compound of Theobroma cacao peels was obtained by maceration and then was analyzed by using GC-MS before fraction. Forty two compounds were identified among the extracts. This essential compound was characterized to obtain a high content of oxygen which leads into its capability to control the corrosion. Corrosion behavior of mild steel in hydrochloric acid solution with addition of Theobroma cacao was determined by conducting EIS method. Surface analysis (SEM-EDX, XPS, and XRD) was also carried out to establish the corrosion inhibitive property of Theobroma cacao peels extract in HCl solution. Inhibition efficiency and resistance polarization was found to increase with increasing concentration of the essential compound in Theobroma cacao peels extract. Nyquist plot showed the charge transfer resistant increase with increasing the inhibitor concentration. The activation energy (Ea) and the heat of adsorption (ΔH) of the corrosion inhibition process suggest that the Theobroma cacao peels extract are chemically adsorbed on the mild steel surface. The inhibition is assumed to occur via chemical adsorption of the inhibitor molecules on the metal surface. The adsorption of inhibitor onto the mild steel surface was found to be a spontaneous process and follow the Langmuir adsorption isotherm. Adsorption occurs at surface in mild steel surface is evidenced by the results of testing SEM-EDX, XPS and XRD. SEM studies confirmed that corrosion protection of mild steel was due to the adsorption of inhibitors. It can be concluded that addition of the extract of Theobroma cacao peels is very promising to be used in reducing the corrosion rate of mild steel. Keywords: Theobroma cacao, Essential compound, Mild steel, XPS, XRD
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INHIBITORY ACTION OF Theobroma cacao PEELS EXTRACT ON CORROSION OF MILD STEEL IN DIFFERENT MEDIA
2016Co-Authors: Yuli Yetri, Emriadi, Novesar Jamarun, GunawarmanAbstract:ABSTRACT The inhibitory effect of extract was obtained from maceration of Theobroma cacao peels on the corrosion of mild steelin HCl 1.5 M and NaCl 1,5M which was investigated by using weight loss and electrochemical measurement techniques. Morphologies surface of sample and chemical composition as well were observed by a scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDX). The results show that the inhibition efficiency increases with increase of Theobroma cacao peels extract concentration. The maximum inhibition efficiency in HCl 1.5 M and NaCl 1.5M was found to be 96.26% (weight loss), 92.68% (Tafel), 95.64% (Rp), 85.78% (EIS) and 91.93% (weight loss), 85.90% (Tafel), 90.19% (Rp) and 75.23% (EIS) for a period of 768h with 2.5%v/v concentration of the inhibitor respectively. Thermodynamic parameters were evaluated from temperature studies. Results were fitted into suitable adsorption isotherms. Electrochemical measurements infer that the extract acted through mixed mode of inhibition. SEM studies confirmed that corrosion protection of mild steel was due to the adsorption of inhibitors. Efforts were made to analyze the effectiveness of peels extract of Theobroma cacao peels in industrial processes. Keywords: Theobroma cacao peels, Mild steel, Corrosion inhibition, GC-MS.
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Green Approach to Corrosion Inhibition of Mild Steel byEssential Compound Peels of Theobroma Cacaoin 1.5M Hydrochliric Acid Medium
2014Co-Authors: Yuli Yetri, Emriadi, Novesar Jamarun, GunawarmanAbstract:ABSTRACT With the increase of Theobroma cacao plantation, cacao peels waste would also increase. The peels of cacao contains of organic compound that can be used as corrosion inhibitor. This compound has advantage in being non toxic and biodegradable. Essential compound of Theobroma cacao peels was obtained by maceration and then was analyzed by using GC-MS and FTIR before fraction. Forty two compounds were identified among the extract. This essential compound was characterized to have a high content of oxygen which leads into its capability to control the corrosion. Corrosion behavior of mild steel in hydrochloric acid solution with addition of Theobroma cacao was determined by conducting weight loss measurements, electrochemical polarization and EIS methods. The effect of temperature and immersion time on the corrosion behaviour of mild steel in HCl 1.5M with and without the TCPE at 2.5% was also studied in 303K to 323K. Surface analysis (Optical microscopy, XPS, XRD, and SEM-EDX) was also carried out to establish the corrosion inhibitive property of Theobroma cacao peels extract in HCl solution. Inhibition efficiency and resistance polarization was found to increase with increasing concentration of the essential compound in Theobroma cacao peels extract. Nyquist plot showed the charge transfer resistant increase with increasing the inhibitor concentration. The activation energy (Ea) and the heat of adsorption (ΔH) of the corrosion inhibition process suggest that the Theobroma cacao peels extract are chemically adsorbed on the mild steel surface. The inhibition is assumed to occur via chemical adsorption of the inhibitor molecules on the metal surface. The adsorption of inhibitor onto the mild steel surface was found to be a spontaneous process and follow the Langmuir adsorption isotherm. Adsorption occurs at surface in mild steel surface is evidenced by the results of testing EDX, XPS and XRD. SEM studies confirmed that corrosion protection of mild steel was due to the adsorption of inhibitors. It can be concluded that addition of the extract of Theobroma cacao peels is very promising to be used in reducing the corrosion rate of mild steel. Keywords: Theobroma cacao, Essential compound, Mild steel, XPS, XRD
