Physico-Chemical Analysis of Soils Used for Pineapple Cultivation in the Sub-Prefectures of Maferinyah and Friguiagbé (Prefectures of Forécariah and Kindia) Republic of Guinea

Over the years, pineapple production in the Republic of Guinea has become less competitive in the West African sub-region, with a world ranking of 144th. It is therefore only natural to review certain parameters in order to improve this ranking. To do this, certain physico-chemical parameters of soil samples from Friguiagbé and Maferinyah (in the Kindia and Forécariah prefectures) were taken and analysed using the following techniques: Pipette de Robinson, Anne, Bray II, Kapen HICDVITZ, Mc. Lead (1982). The analytical results show that the soils at Friguiagbé in Kindia and Maferinyah in Forécariah are acidic, with pH values of 4.4 and 4.7 (fields I and II) and 4.8 and 4.7 (fields I and II) respectively. The soils have a silty-sandy texture. This study could therefore serve as a guide for the Ministry of Agriculture of the Republic of Guinea.

AcWRKY28 mediated activation of AcCPK genes confers salt tolerance in pineapple(Ananas comosus)

Unfavorable environmental cues severely affect crop productivity resulting in significant economic losses to farmers. In plants, multiple regulatory genes, such as the WRKY transcription factor (TF) family, modulate the expression of defense genes. However, the role of the pineapple WRKY genes is poorly understood. Here, we studied the pineapple WRKY gene, AcWRKY28, by generating AcWRKY28 over-expressing transgenic pineapple plants. Overexpression of AcWRKY28 enhanced the salt stress resistance in transgenic pineapple lines. Comparative transcriptome analysis of transgenic and wild-type pineapple plants showed that “plant-pathogen interaction” pathway genes, including 9calcium-dependent protein kinases (CPKs), were up-regulated in AcWRKY28 over-expressing plants. Furthermore, chromatin immunoprecipitation and yeast one-hybrid assays revealed AcCPK12, AcCPK3, AcCPK8, AcCPK1, and AcCPK15 as direct targets of AcWRKY28. Consistently, the study of AcCPK12 over-expressing Arabidopsis lines showed that AcCPK12 enhances salt, drought, and disease resistance. This study shows that AcWRKY28 plays a crucial role in promoting salt stress resistance by activating the expression of AcCPK genes.

Chemical Composition of Pineapple Press Residues (Ananas comosus) and Effect on Growth Performance of Rabbit (Oryctolagus cuniculus)

With a view to improving rabbit production performance, a trial on the chemical composition of pineapple press residue (Ananas comosus) and the effect of its incorporation in the ration on rabbit growth performance (Oryctolagus cuniculus) was carried out at the KUATE Cunicole Farm in Bandjoun, in Western Cameroon. To do this, 36 rabbits of the local breed, aged 53 days with an average weight of 1337 ± 119 g were distributed and randomly assigned to 3 experimental rations corresponding respectively to treatments or batches T0, T1 and T2. The animals in treatment T0 received a ration containing no pineapple press residue, while those in treatments T1 and T2 received a ration containing 20% and 40% pineapple press residue, respectively. These residues were dried and ground for chemical composition analysis. The feed served as well as refusals from the previous day were weighed each morning to assess feed intake. The animals were weighed every 7 days to assess weight performance. At the end of the trial which lasted 7 weeks, the animals were fasted for 24 hours, then sacrificed to evaluate carcass characteristics and the relative weights of some digestive organs. The results of this study showed that pineapple press residues had a high crude fiber content (19.2%) and energy (2500 Kcal/kg DM). Their incorporation had no significant effect on feed intake and feed conversion ratio. The average live weight, weight gain and average daily weight gain of the animals receiving the ration with 20% inclusion of pineapple press residue were comparable to those of the control group and significantly higher than those of animals fed with 40% inclusion of pineapple residue. The highest carcass yields were obtained with rabbits fed 20% pineapple press residue in their ration. The cost of feed for the production of a kilogram live weight of rabbit tends to decrease with the ration incorporated with 20% pineapple press residue. Pineapple press residues constitute a by-product that can be recycled and their incorporation at 20% can increase rabbit growth performance and reduce production costs.

Physico-Chemical and Microbiological Study of Fresh Pineapple(Baronne de Guinée)Grown in the Sub-prefectures of:Maferinyah and Friguiagbé(Forécariah and Kindia Prefectures),Republic of Guinea

Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physico-chemical in order to improve this classification.To do this,instead of buying samples on the market,the aim is to analyze fresh samples harvested in the production fields and send them to the laboratory for analysis of certain physico-chemical and microbiological parameters.Analytical results showed that the Brix content in fields I and II at Maferinyah(Forécariah)was higher(14.35 and 16.5)than that found in fields I and II at Friguiagbé(Kindia)(14.2 and 12.4),The pH of fruit from both localities varies between 3.48 and 3.56,with the highest acidity value found in Field I at Friguiagbé(Kindia)2.16 and the lowest value in Field II at Maferinyah(Forécariah)0.46.Moisture contents for both localities ranged from 82.56 to 89.5,with the highest value found at Field I in Maferinyah(Forécariah)89.5.Dry extract and ash in both localities would be in the range 10.54 to 17.45;0.33 to 1.43 respectively.The highest values for dry extract and ash were found in Fields I and II Friguiagbé(Kindia)17.45 and 1.43.The samples analyzed contained certain trace elements such as magnesium,sodium,iron and phosphorus.Microbiological analyses showed the presence of Escherichia coli(E.coli),yeast-molds,Staphylococcus aureus and the absence of salmonella.

Optimization of the Pretreatment of the Mixture of Cassava Peelings and Pineapple Fibers Using Response Surface Methodology and a Process Simulator for the Bioethanol Production

The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production of bioethanol remains a challenge given the crystallinity of cellulose and the presence of the complex. The pretreatment aimed to solubilize the lignin fraction and to make cellulose more accessible to the hydrolytic enzymes, was done using the organosolv process. A mathematical modeling was performed to point out the effect of the temperature on the kinetics of the release of the reducing sugars during the pretreatment. Two mathematical model was used, SAEMAN’s model and Response surface methodology. The first show that the kinetic parameters of the hydrolysis of the cellulose and reducing sugar are: 0.05089 min-1, 5358.1461 J·mol-1, 1383.03691 min-1, 51577.6100 J·mol-1 respectively. The second model was used. Temperature is the factor having the most positive influence whereas, ethanol concentration is not an essential factor. To release the maximum, an organosolv pre-treatment of this sub-strate should be carried out at 209.08°C for 47.60 min with an ethanol-water ratio of 24.02%. Organosolv pre-treatment is an effective process for delignification of the lignocellulosic structure.

Effect of Ultrasound and Thermal Pasteurization on Physicochemical Properties and Antioxidant Activity of Juice Extracted from Ripe and Overripe Pineapple

It has become necessary to assess how food processing methods affect qualitative qualities due to the increased consumer awareness of the health benefits of various nutrients in food. In the current study, the effects of ultrasound treatment (37°C, 5 min), pasteurization (90°C, 5 min), and their combination on quality parameters, including pH, total soluble solids (TSSs), titratable acidity (TA), color values (L*, a*, b*), ascorbic acid (AA), total phenolic content (TPC), and antioxidant activity (DPPH), of pineapple juice from ripe and overripe pineapples were assessed. Color values (L*), ascorbic acid (AA), total phenolic content (TPC), and DPPH radical scavenging activity in all juice samples that were sonicated alone and in combination with pasteurization improved significantly (p and color value (a* and b*) decreased in comparison to the control. Whereas pH and acidity did not change significantly (p < 0.05). Pasteurization significantly (p , but sonicated samples significantly (p quality parameters and antioxidant activity, notably in ripe juice. Overall, pasteurization degraded these liquids but sonication, either alone or in combination with it, was advantageous for preserving their quality by retaining nutrients.

Epigenetic modification mechanisms of chloroplasts mutants in pineapple leaves during somatic regeneration

Somaclonal variation in tissue culture is a common phenomenon induced by various external or internal environmental conditions,resulting in heritable or non-heritable alterations in gene expression. One crucial mechanism involved in plant growth and development is epigenetic regulation. A highly dynamic epigenome can respond to environmental changes by regulating gene expression. DNA methylation is one of these epigenetic modifications that can alter gene expression in tissue-cultured pineapple plants. The underlying mechanism of such somaclonal variations in pineapple and the epigenetic regulation involvement in somaclonal variations has not been studied. This study performed DNA methylome and transcriptome sequencing of wild-type(WT) and mutant pineapple plants(WS, HW, and TW). We observed altered DNA methylation patterns in chlorophyll development in the mutants. Specifically, we noticed that the methylation levels in the CHG and CHH contexts were lower in the gene body regions compared to the upstream and downstream regions. We identified several thousand differentially methylated regions(DMRs) located at the gene body regions, some of which overlapped with the differentially expressed genes(DEGs). Functional enrichment analyses suggested that these genes were involved in chlorophyll metabolism. Thus, our results revealed that the transcriptional regulation of many chlorophyll metabolic essential genes could be regulated by DNA methylation caused by somaclonal variations and provided insights into epigenetic mechanisms underlying the regulation of chlorosis in pineapple plants.

Extensive Pineapple Production Constraints and Land Suitability in the Centre Region of Cameroon

The low level of productivity observed in pineapple fields in Centre Came-roon must be sustainably reduced in order to increase producers’ income while using the same resources. The identification and control of production constraints are key steps in optimizing the use of limited resources. To this end, the FAO land assessment methodology following the Fuzzy-MCDM pro-tocol was used for the two pineapple production basins in the Centre, namely Awae and Bokito. It was found that the land in Awae Basin is moderately suitable S2sf with constraints imposed by texture, pH and base saturation. In the Bokito Basin, 25% of the land is suitable S1wf and 75% is moderately suitable S2wsf with constraints imposed by soil texture (27%), temporary soil water saturation (99%), pH, base saturation and exchangeable sodium. Constraint correction improves the land index (potential suitability) and re-mains limited by permanent constraints that cannot be corrected. Improve-ment of the technical itinerary through modification of plant densities, selec-tion of improved cultivars and balanced fertilization must be undertaken to optimize pineapple production in Centre Cameroon.

Comparative Study of Biogas Production from Jackfruit Waste, Banana Peels, and Pineapple Peels Co-Digested with Cow Dung

Only 42% of Uganda’s population has access to electricity. The population continues to use firewood and charcoal as a source of energy, which leads to depletion of forests thus to climate change. The purpose of this study was to assess the potential of biogas production from jackfruit waste, banana peels, and pineapple peels when co-digested with cow dung as an alternative energy source. Substrates for each waste were co-digested with varying proportions (0%, 25%, and 50%) of cow dung using laboratory-scale 250 mL anaerobic digestors. The total biogas generation for jackfruit waste, banana peels, and pineapple peels after 30 days of anaerobic digestion was 82.3, 189, and 262 mL, respectively. When jack fruit waste, pineapple peels and banana peels were co-digested with 25% cow dung, the total amount of biogas produced increased by a factor of two and three, respectively. However, 50% of cow dung only significantly (p ≤ 0.05) improved for jack fruit waste by two folds. Therefore, the results indicated that jackfruit waste, banana and pineapple peels can be used for biogas production to augment energy supply. .

Plant Regeneration through Indirect Organogenesis in Two Cultivars of Pineapple (Ananas comosus L.)

Unavailability of performant planting material of pineapple constitutes a major problem of its cultivation in Africa. For this purpose, indirect organogenesis technique is used to evaluate the in vitro responses of two cultivars of pineapple during the explant’s regeneration. Calli were induced from crown leaf and plantlets leaf of “Smooth Cayenne” and “Sugarloaf cultivars”. Murashige and Skoog medium with vitamins B5 supplemented with different growth regulators combinations were used. BAP and/or 2,4-D have been added to base medium for calli cells’ differentiation while BAP and GA3 have been added for plant elongation. The results indicated that explants from regenerated plantlets leaves cultivated on MS supplemented with copper (II) sulphate 5-hydrate concentrations incorporated had significant (p < 0.0001) influence on callus induction in pineapple cultivars. Likewise, MS medium with NAA (0.5 mg/l) + BAP (1 mg/l) had a highly significant influence with 8.8 differentiated Calli. Also, MS medium supplemented with BAP (3 mg/l) + GA3 (2 mg/l) for the “smooth Cayenne” had significantly influenced (p < 0.0001) Calli regeneration with a high rate of 55.25% plantlets. MS medium containing 0.5 mg/l of NAA + 0 mg/l IBA produced a high number of roots in Sugarloaf whereas the medium containing 1.5 mg/l NAA + 0.5 mg/l (IBA) produced high number of roots in smooth Cayenne. We have established an efficient and reproducible protocol for mass propagation and genetic transformation of pineapple though indirect organogenesis. This protocol may be used in genetics engineering studies for pineapple breeding.

An updated review of pineapple and its bioactive compounds in breast cancer

Women are more likely than men to develop cancer of the breast.Most breast cancer drugs are highly toxic,and treatment can cause side effects.It is imperative to find safe alternative medicines in the pursuit of a cure for breast cancer.An extract of pineapple contains cysteine proteases known as bromelains.In general,pineapples are regarded as safe foods.From the fruit,stem,and of pineapples,bromelain is produced by multiple endopeptidases.As well as reducing the growth of tumors locally,bromelain severely impaired the cytotoxicity of monocytes in the immune system in the fight against cancer.Specifically,we investigated pineapple’s possible mechanisms of action and its bioactive compounds in breast cancer.

Effects of Nitrogen and Potassium Fertigation on Yield and Quality of Pineapple during Late Growing Period

[Objective] The aim was to compare effects of nitrogen and potassium fertigation on yield and quality of pineapple during the late growing period. [Method] Urea, potassium sulfate, and potassium chloride were taken as three fertilizers which were set at three levels, respectively, and the group without additional fertilizers was taken as control group. [Result] Compared with control group, weight of individual pineapple was significantly increased by fertigation of urea at 7.5 kg or potassium sulfate at 18 kg per 667 m 2 and the increase yields were 22.5% and 28.9%, respectively. Effects of nitrogen and potassium fertigation on yield and quality of pineapple were compared. [Conclusion] Potassium sulfate fertigation would promote sugar accumulation and improve quality of fruits. Furthermore, chlorophyll content can be enhanced and photosynthetic capacity can be reinforced.

Identification and Biological Characteristics of Pineapple Anthracnose in Hainan Province

[Objective]The pathogen of pineapple anthracnose were isolated and identified,and the biological characteristics of the pathogen were studied.[Method]Pathogen was isolated and purified from the leaves collected from different areas in Hainan province which had been infected by pineapple anthracnose,and the biological characteristics were studied as well as morphological identification of the pathogen.[Results] The pathogen of pineapple anthracnose was identified as Colletorichum gloeosprioides Penz.through morphological characteristics.The results of biological characteristic test showed that the optimum temperature for mycelium growth and spore germination were 25-30 and 28-30 ℃,respectively;and the optimum pH value was 6.0-8.0;complete darkness was the best condition for growth of mycelium,while alternative light and darkness was most beneficial for spore germination;the best carbon sources for mycelium growth were glucose,D-fructose and maltose;except for L-arabinose and D-galactose,the other carbon sources all had promotion effect on spore germination;yeast extract,peptone and beef extract were proved to be beneficial for mycelium growth and spore germination.Aspartic acid was only beneficial for spore germination;spores were just able to germinate when the relative humidity（RH）was greater than 90%,spore germination was the highest under water drops condition.[Conclusion]The results laid preliminary basis for the control of pineapple anthracnose.

Modulatory effect of pineapple peel extract on lipid peroxidation,catalase activity and hepatic biomarker levels in blood plasma of alcoholinduced oxidative stressed rats

Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 niL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3000 rpm for 10 min.The plasma was analyzed to evaluate malondialdehyde(MDA),catalase activity,aspartate aminotransferase(AST),alkaline phosphatase(ALP) and alanine aminotransferase(ALT) concentrations.Results:Administration of alcohol caused a drastic increase(87.74%) in MDA level compared with the control.Pineapple peel extract significantly reduced the MDA level by 60.16%at 2.S mL/kg bw.Rats fed alcohol only had the highest catalase activity,treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity.Increased AST,ALP and ALT activities were observed in rats fed alcohol only respectively,treatment with pineapple peel extract drastically reduced their activities. Conclusions:The positive modulation of lipid peroxidation,catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcoholinduced oxidative stress is an indication of its protective ability in the management of alcoholinduced toxicity.

Effect of Fiber Loadings and Treatment on Dynamic Mechanical, Thermal and Flammability Properties of Pineapple Leaf Fiber and Kenaf Phenolic Composites

This study deals with the analysis of dynamic mechanical,thermal and flammability properties of treated and untreated pineapple leaf fiber(PALF)and kenaf fiber(KF)phenolic composites.Results indicated that storage modulus was decreased for all composites with increases in temperature and pattern of slopes for all composites,having almost the same values of E′at glass transition temperature(Tg).The peak of the loss modulus of pure phenolic composites was shown to be much less.After the addition of kenaf/PALF,peaks were higher and shifted towards a high temperature.The Tan delta peak height was low for pure phenolic composites and maximum for 60%PALF phenolic composites.Cole-Cole analysis was carried out to understand the phase behavior of the composite samples.Thermogravimetric analysis(TGA)results indicated that pure phenolic composites have better thermal stability than PALF and kenaf phenolic composites.Vertical and horizontal UL-94 tests were conducted and showed pure phenolic resin is highly fire resistant.The overall results showed that treated KF composites enhanced the dynamic mechanical and thermal properties among all PALF/KF composites.

Productivity and nutrient cycling in an agroforestry ecosystem for interplant of pineapple and coconut

In this paper, the biomass productivity and nutrient cycling in an agroforestry system of coconut (Cocus nucifera) interplanted with pineapple (Ananas comosus) had been studied. The result showed that the biomass productivity of this ecosystem was 47 460 kg...hm2...a?1, which was 4.3 times as much as that of pure coconut plantation. In the biological cycling of N, P. K elements, the total annual retention was 559.470 kg...hm?2, the annual return was 410.745 kg...hm?2, the annual uptake was 970.475 kg...hm?2, respectively. The average circulation rate in three nutrient elements (N, P, K) was 42.32%, which was 27.53% more than that in pure coconut stands. Coconut interplanted with pineapple was proved to be one of optimum cultural patterns, which had the higher biomass productivity, and better usage efficiency of environment resources in tropical areas.

Effect of Hybridization on the Mechanical Properties of Pineapple Leaf Fiber/Kenaf Phenolic Hybrid Composites

In this study,pineapple leaf fiber(PALF),kenaf fiber(KF)and PALF/KF/phenolic(PF)composites were fabricated and their mechanical properties were investigated.The mechanical properties(tensile,flexural and impact)of the PALF/KF/PF hybrid composites were investigated and compared with PALF/KF composites.The 3P7K exhibited enhanced tensile strength(46.96 MPa)and modulus(6.84 GPa),flexural strength(84.21 MPa)and modulus(5.81 GPa),and impact strength(5.39 kJ/m2)when compared with the PALF/PF and KF/PF composites.Scanning electron microscopy(SEM)was used to observe the fracture surfaces of the tensile testing samples.The microstructure of the 7P3K hybrid composite showed good interfacial bonding and the addition of KF improved the interfacial strength.It has been concluded that the 3P7K ratio allowed obtaining materials with better mechanical properties(tensile,flexural and impact strengths)than PALF/PF and KF/PF composites.The results obtained in this study will be used for further comparative study of untreated hybrid composites with treated hybrid composites.

The Cause for Water-Heart Fruit of Pineapple and Protective Measurements

Pineapple industry has played important roles in China’s economics in tropical- and subtropical-areas. Pineapple industry in China has been damaged by water-heart fruit. The objective of this research is to clarify the mechanism underlying water-heart fruit of pineapple and find ways for preventing water-heart fruit. We found that water logging can cause water-heart pineapple. The longer the pineapple plants were water logged, the more fruits were found water heart. With the development of fruits, the fruits’ sensitivity to water logging increased. Spraying potassium sulfate onto the fruits after the plants are water logged can decrease the rate of pineapple water-heart. But this effect became less with the fruit development. When sucrose and its precursors in intracellular space were transferred into sink cells, hydrogen ions were required. Because of lacking hydrogen ions, sucrose and its precursors were stopped in intracellular space and seized water from cells. Water-heart fruit formed. If potassium can be gotten in intracellular space, the roles of hydrogen ions might be replaced with potassium ions. With the help of potassium ions, sucrose and its precursors were transported into sink cells and the water-heart symptoms alleviated.

The Situation and Challenges of Pineapple Industry in China

Pineapple is the third largest tropical fruit in China. Pineapple industry played important roles in developing economies in tropical- and subtropical-areas in China. However, the structure of varieties is simple. The harvesting period is centralized. The price of pineapple fruits is often low. These challenges hindered the further development of pineapple industry. The people engaged in pineapple industry should select and cultivate new varieties with higher qualities and that can be harvested in a longer period. More work should be done in the technology on inducing inflorescence of new varieties. Precision fertilization for new varieties should be researched and developed. The technology for cultivating tissue-culture seedlings fast and at low cost should also be studied. The diseases in fruits should be prevented and controlled before harvesting.

Effects of Light on Sweet Potato （Ipomoea Batatas L.）, Cowpea （Vigna Unguiculata L.） and Pineapple （Ananas Comosus L.）

An experiment was carried out at Mkuranga Research Station of National Coconut Development Programme （NCDP） to study the effect of light regimes on three different crops which are sweet potato, cowpea and pineapple between 1995 and 1996. Four light intensities with nominal values of light transmission namely L0 = 100%, L 1 = 75%, L2 = 50%, L3 = 25% were provided by nylon netting materials which filtered sunlight to varying light percentages. The experiment was a split-plot on randomized complete block design, replicated four times. Growth measurements and yield were recorded at a regular interval in all crops. Leaf morphological characteristics were carried out only on sweet potato. Result on the leaf morphological characteristics showed light intensity strongly influenced growth and development of sweet potato. Specific leaf area values in full light were smaller than those in under heavy shade. The light intensity increased the cowpea seed yield significantly （P 〈 0.01） and the interaction between seasons （year） x light regimes was significant （P 〈 0.01）. In low intensity, pineapple flowered earlier and yielded more than in high intensity. These results have provided useful information in planning intercropping models in coconut based-farming systems in Tanzania.