Cherimoya Fruit Research Articles

Study of the Pectinase Production from Soursop and Cherimoya Pulp for Agro-Industrial Waste Reduction in Colombia

Pectic enzymes are an eco-friendly alternative to improve extraction processes for the food industry. The objective of the research was to obtain pectinase from the pulp of soursop (Annona muricata L.) and cherimoya (Annona cherimola L.), as an alternative to reduce agro-industrial waste in Colombia; involving the study of the factors influencing the protein content of the enzymes extracted from different stages and types of fruits, the conditions for enzymatic activity, and the potential application in the food industry, particularly in extraction processes and juice clarification. A factorial design 23, spectrometric and potentiometric techniques evidenced that the protein content depends on factors such as fruit stage (suitable “s” and unsuitable “u” fruits for consumption) and fruit type (soursop and cherimoya). The higher protein content was obtained by the precipitation method in comparison to ion exchange chromatography. Cherimoya fruit presented a higher protein content of 326 ± 26 mg by precipitation, however, the soursop samples evidenced higher enzymatic activity, 2.2 ± 0.1 U/mL. The pectinase obtained was an acidic enzyme of type pectin methylesterase with an enzymatic activity of 27.0 ± 0.9 U/mL, under the optimal conditions of pH 4 and temperature of 40 °C. The application in blackberry juice evidenced a decrease in the absorbance and pH changes. From the current research, the pulp of soursop and cherimoya was proven as a cheap source to obtain pectinase with enzymatic activity for juice clarification, and this process is an alternative to reduce the negative impact on the environment and an economical source for the local producers.

Melatonin Treatments Reduce Chilling Injury and Delay Ripening, Leading to Maintenance of Quality in Cherimoya Fruit

Spain is the world's leading producer of cherimoya, a climacteric fruit highly appreciated by consumers. However, this fruit species is very sensitive to chilling injury (CI), which limits its storage. In the present experiments, the effects of melatonin applied as dipping treatment on cherimoya fruit CI, postharvest ripening and quality properties were evaluated during storage at 7 °C + 2 days at 20 °C. The results showed that melatonin treatments (0.01, 0.05, 0.1 mM) delayed CI, ion leakage, chlorophyll losses and the increases in total phenolic content and hydrophilic and lipophilic antioxidant activities in cherimoya peel for 2 weeks with respect to controls. In addition, the increases in total soluble solids and titratable acidity in flesh tissue were also delayed in melatonin-treated fruit, and there was also reduced firmness loss compared with the control, the highest effects being found for the 0.05 mM dose. This treatment led to maintenance of fruit quality traits and to increases in the storage time up to 21 days, 14 days more than the control fruit. Thus, melatonin treatment, especially at 0.05 mM concentration, could be a useful tool to decrease CI damage in cherimoya fruit, with additional effects on retarding postharvest ripening and senescence processes and on maintaining quality parameters. These effects were attributed to a delay in the climacteric ethylene production, which was delayed for 1, 2 and 3 weeks for 0.01, 0.1 and 0.05 mM doses, respectively. However, the effects of melatonin on gene expression and the activity of the enzymes involved in ethylene production deserves further research.

Pomological, Sensorial, Nutritional and Nutraceutical Profile of Seven Cultivars of Cherimoya (Annona cherimola Mill).

In this work, the food quality of four international (Campas, Chaffey, Fino de Jete and White) and three local (Daniela, Torre1 and Torre2) cultivars of Cherimoya (Annona cherimola Mill) was investigated. With this aim, pomological traits, sensorial attributes, physiochemical parameters (pH, total soluble content and total acidity), nutritional composition (macro- and micro-nutrients) and nutraceutical values (bioactive compounds, radical scavenging and antioxidant properties) were evaluated. Among the seven observed cultivars, Fino de Jete was identified as the best, not only for its commercial attributes such as pomological traits and physiochemical values, but also for its nutritional composition. On the other hand, Chaffey and Daniela were the cultivars with the highest content of polyphenols, proanthocyanidins, and with the strongest antioxidant capacity. Concerning the two local ecotypes, Torre1 and Torre2, they displayed a balanced nutritional profile that, if combined with their discrete nutraceutical, physicochemical and pomological values, may result in a reassessment of their commercial impact. In conclusion, our data provide interesting information about the pomological, nutritional, and nutraceutical properties of cherimoya fruits. Our results, in addition to promoting the commercial impact of local cultivars, may increase the use of individual cultivars in breeding programs.

Effects of the Pollen Parent on Cherimoya Fruit Set and Quality

Effects of the Pollen Parent on Cherimoya Fruit Set and Quality

Changes in nutrient contents in peel, pulp, and seed of cherimoya (Annona cherimola Mill.) in relation to organic mulching on the Andalusian tropical coast (Spain)

Cherimoya, a tropical fruit from South America whose commercial demand is increasing for both its exceptional flavor and high nutritional content, is expanding in cultivation to subtropical areas such as the Mediterranean coast of Andalusia (Spain). In this paper, we analyze cherimoyas (peel, pulp, and seed) grown in Almuñécar (Granada, Spain) during the years 2013, 2015, and 2016 from trees applied with different pruning wastes (avocado, cherimoya, mango, and garden). The cherimoya fruits had high contents in most of the macronutrients, especially K, Ca, and micronutrients such as Fe and Zn. The Na, P, K and Ca concentrations were related to the plant mulch that released nutrients to the soil and led to a variation in soil-nutrient bioavailability by decreasing the soil pH. The seed was the part of the cherimoya that registered the least nutritional change due to annual weather differences and the highest positive effects of mulching in terms of increased nutrient availability after mulching.

EFECTO DE LA DENSIDAD DE PLANTACIÓN EN LA CALIDAD DEL FRUTO DE CHIRIMOYA (Annona cherimola MILL.)

<p>Cherimoya (<em>Annona cherimola</em> Mill.) is a commercially import fruit crop in several countries of Latin America (Ecuador, Peru and Chile) and Europe (Spain). The fruit is highly valued for its good organoleptic characteristics and nutritional value. Currently, there is a worldwide trend to implement high planting densities in several fruit crops. However, there is little information available on cherimoya to implement new commercial orchards. This research evaluated three planting densities (625, 1250 and 2500 plants/ha) to determine their effect on the cherimoya fruit quality of the variety 'Cumbe'. The two lowest densities evaluated doubled the yield compared to the highest density, and also obtained the highest percentages of fruit in the best size categories (super extra and extra), and harvesting fruit weights >400 g. Based on the results of this study, planting densities of 2500 plants/ha or higher are not recommended due to the affect on yield and quality of cherimoya fruit.</p>

An improved method for a fast screening of α-glucosidase inhibitors in cherimoya fruit (Annona cherimola Mill.) applying effect-directed analysis via high-performance thin-layer chromatography-bioassay-mass spectrometry

α-glucosidase inhibitors (AGIs) are very attractive bioactive compounds due to their therapeutic profile that includes beneficial effects over glycemic control in type 2 diabetes mellitus and viral infections. Its detection and identification in plants and fruits has gained growing attention, and certainly requires efficient screening methodologies. The objective of the present work was to develop a fast methodology to detect and identify AGIs in cherimoya fruit (Annona cherimola Mill.) applying effect-directed analysis via high-performance thin layer-chromatography (HPTLC) linked with bioassay and mass spectrometry (MS). Both, HPTLC and bioassay conditions, were optimized accomplishing 50% and 83% reduction on enzyme concentration and incubation time respectively, compared to the original method. Additionally, the contrast between inhibitory bands and purple background was also enhanced by enzyme substrate impregnation on HPTLC plate. The optimized detection conditions established were the following: 5.0 U mL−1 of enzyme solution, 1.0 mg mL−1 of 2-naphthyl-α-D-glucopyranoside substrate, 1.0 mg mL−1 of Fast Blue B salt solution and 10 min as incubation time. Applying this methodology, coupled to HPTLC-MS and ultra-high-performance liquid chromatography (UHPLC)-diode array detector (DAD)-MS/MS, it was possible for the first time to detect and identify three AGIs in cherimoya peel and seeds. Compounds were tentatively assigned as phenolamides (phenylethyl cinnamides): N-trans-feruloyl tyramine (m/z 314 [M+H]+; UV λmax 293 and 316 nm), N-trans-p-coumaroyl tyramine (m/z 284 [M+H]+; UV λmax 296 nm) and N-trans-feruloyl phenethylamine (m/z 298 [M+H]+; UV λmax 288 nm). To the best of our knowledge, the presence of latter compound is reported for the first time in cherimoya.

Detection and identification of acetylcholinesterase inhibitors in Annona cherimola Mill. by effect-directed analysis using thin-layer chromatography-bioassay-mass spectrometry.

Acetylcholinesterase (AChE) inhibitors are considered an important strategy in the treatment of neurological disorders such as Alzheimer's disease. A simple and fast planar chromatography-bioassay methodology has been established to detect bioactive molecules in cherimoya fruit. Detect and identify AChE inhibitors in cherimoya by high-performance thin-layer chromatography (HPTLC)-bioassay-mass spectrometry (MS) and related techniques. Effect-directed analysis by planar chromatography-bioassay-mass spectrometry was applied to detect and identify AChE inhibitors in pulp, peel and cherimoya seed. Bioassay was optimised establishing the following conditions: enzymatic solution (1.0UmL-1 ), 1-naphtyl acetate substrate (1.5mgmL-1 ) and Fast Blue B salt (1.0mgmL-1 ). TLC-MS interface was used to directly elute the active zones into a mass spectrometer or to a micro-vial for further off-line studies. Two AChE inhibitory bands were detected in peel extracts. An analysis via HPTLC-MS and high-performance liquid chromatography diode array detector tandem mass spectrometry (HPLC-DAD-MS/MS) allowed to characterise three potential AChE inhibitors: anonaine (m/z 266 [M+H]+ ; UV λmax = 269.6nm), glaucine (m/z 256 [M+H]+ ; UV λmax = 282.9 and 300.6nm) and xylopine (m/z 296 [M+H]+ ; UV λmax = 278.5nm). The application of this optimised high throughput method allowed to establish the presence of three potential AChE inhibitors in cherimoya peel. For the first time AChE inhibitory capacity of these alkaloids is reported.

Compuestos fenólicos y actividad antioxidante de los extractos de la hoja de chirimoya (Annona cherimola Mill)

Después de la cosecha del fruto chirimoya, los árboles liberan enormes cantidades de hojas, las cuales son quemadas por los agricultores. Este trabajo muestra que las hojas pueden ser usadas para nuestro beneficio como antioxidante. Se determinaron los compuestos fenólicos (CF) y la actividad antioxidante (AA) de los extractos de la hoja seca de Annona cherimola Mill en etanol al 70% v/v, agua a 80 °C, y agua subcrítica (AS) a 110, 120 y 130 °C, siguiendo un diseño factorial con el programa Minitab. Los CF se cuantificaron con la metodología de Folin Ciocalteu y la AA con el 2,2-difenil-1-picrilhidrazilo (DPPH) y con el poder antioxidante reductor del hierro (FRAP). Los resultados indicaron que el tipo de solvente y el tiempo de extracción presentaron un efecto significativo en el contenido de CF y AA de los extractos. Se concluyó que el extracto de hoja de chirimoya es un potencial antioxidante. El extracto de AS a 130 °C presentó el mayor contenido de CF (5,6 g EAG/100 g de hoja seca) y el extracto etanólico presentó mayor AA (0,86 mg equivalente trolox/mg extracto seco; IC50=0,020 mg de extracto seco/mL de extracto de hoja seca y FRAP de 1710,14 μmol equivalente trolox /g de hoja seca) y los extractos obtenidos con AS a menor temperatura presentaron mayores valores de AA.

An ultra-low pressure pneumatic jamming impact device to non-destructively assess cherimoya firmness

The quality of cherimoya fruit is reduced by the rapid deterioration of firmness during ripening. Different methods have been developed for the measurement of firmness. The objective of this study was to use a developed impact prototype for the non-destructive assessment and prediction of cherimoya fruit firmness. The prototype has an ultra-low pressure pneumatic jamming rod used to copy the irregular fruit shape. A sample of 200 cherimoyas from Malaga (Spain) ‘Fino de Jete’ were tested during 4 days. Every day all the fruits were non-destructively tested and a set of 15 were destructively tested. On the fourth day all the remaining fruits were also destructively tested. The prototype was capable of copying the irregularities of the fruit and non-destructively assessing the decrease in cherimoya firmness during ripening without causing damage. A high correlation was found between destructive firmness and non-destructive variables from the prototype. A PLS model was developed to relate destructive firmness from day 4 to non-destructive variables and diameter from day 3, with a R2 of 75.6 and a RMSECV of 0.9885. A calibration set confirmed the prediction with a R2 of 80.2 and a RMSEP of 0.0561. Firmness decay could be non-destructively predicted 24 h in advance using the variables extracted from the prototype device signal.

FIRST REPORT OF ANTHRACNOSE ON CHERIMOYA CAUSED BY COLLETOTRICHUM TROPICALE IN CUBA

Cherimoya (Annona cherimola Mill.) fruits with preharvest anthracnose symptoms were collected in Province Artemisa, Cuba, in April 2015. Necrotic, sunken lesions with orange spore masses were observed on 71% of the fruits. Single spore isolations on potato dextrose agar (PDA) were initially white and became light gray with scant aerial mycelium and abundant orange conidiomata in concentric rings. Conidia were 12.5-17.5 × 5-6.5 µm, subcylindrical with rounded ends, aseptate and hyaline, morphological characters consistent with Colletotrichum tropicale (Rojas et al., 2010). To confirm pathogen identity, the ITS region, the Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) gene (ApMat) and a partial sequence of the glutamine synthetase gene (GS) were amplified and sequenced (European Nucleotide Archive Accession Nos. LT853592, LT853593 and LT853594, respectively). A phylogenetic analysis using Bayesian inference with published ApMat, GS, and ITS data for Colletotrichum species in the C. gloeosporioides complex (Jayawardena et al., 2016) placed our isolate INIFAT 4144 in the C. tropicale clade. For assessing pathogenicity, five detached cherimoya fruits were inoculated with a suspension of 105 spores/ml by depositing 30 µl droplets of the suspension on the surfaces of nonwounded and wounded fruits with a sterile needle. Control fruits received sterile water. Typical anthracnose symptoms were observed in all inoculated fruits after 3 to 5 days. Control fruits presented no symptoms. The pathogen was consistently re-isolated from the infected fruits. To our knowledge, this is the first report of C. tropicale in Cuba and the first report on A. cherimola.

Influence of postharvest citric acid and chitosan coating treatment on ripening attributes and expression of cell wall related genes in cherimoya (Annona cherimola Mill.) fruit

ABSTRACT We investigated the effects of citric acid and chitosan coating on the fruit ripening attributes of cherimoya (Annona cherimola Mill.) stored at 15 ± 1 °C for 10 days. Compared to the controls, a combined treatment of citric acid and chitosan coating delayed the browning, splitting, and decay, maintained firmness, and inhibited the increase in respiration rate of the cherimoya fruits. The inhibition of softening and splitting was associated with decreases in the activities of pectin methylesterase and polygalacturonase and solubilization/degradation of pectin ensued. The citric acid and chitosan coating treatment delayed the softening and splitting of the harvested cherimoya fruits by regulating the CMCase activity and starch-sugar conversion. Throughout the storage period, the citric acid and chitosan coating treated cherimoya fruits also exhibited a lower polyphenol oxidase activity and higher superoxide dismutase, peroxidase, and catalase activities compared with the controls. Moreover, the production of superoxide free radicals and content of malondialdehyde were significantly declined in the treated fruits. Furthermore, the expression patterns of several cell wall-related genes in cherimoya were analyzed by quantitative real time PCR. The data showed that all these genes, including three AcXETs, three AcEXPs and one AcPE, exhibited highly diversified expression patterns during the fruit softening. AcXET1 and AcXET2 showed highest expression levels on the time points 6-d and 8-d, while the accumulation of AcEXP3 notably increased on the time point 6-d. The citric acid and chitosan coating treatment delayed the accumulation of AcXEP1, AcEXP1, AcEXP1 and AcPE by reducing their mRNA levels. Our findings suggest that treatment with 20.0 mM citric acid combined with 1.00% chitosan can provide an effective approach to maintain postharvest quality and extend the shelf life of cherimoya.

Characterisation of odour‐active compounds in cherimoya (Annona cherimola Mill.) fruit

AbstractOptimized solid‐phase microextraction GC‐Olfactometry, and solvent‐assisted flavour evaporation, combined with aroma extract dilution analysis and with the determination of odour activity values by quantitative GC‐FID and GC‐MS were used to analyse volatile compounds from cherimoya fruit and to estimate the most odour‐active compounds. The analysis led to the identification of 92 compounds, 78 of them were positively identified. 18 odourants were considered as potentially odour‐active compounds and contribute to the typical cherimoya aroma, from which 3‐methylbutyl butanoate, α‐pinene, methyl 2‐methylbutanoate, butyl butanoate, and 3‐methylbutyl 3‐methylbutanoate were the most odour‐active compounds. HS‐SPME‐GC‐O has a great potential as fast and simple tool to control and assess aroma quality of cherimoya fruit. Copyright © 2015 John Wiley & Sons, Ltd.

Inhibición del bronceado en cáscara de chirimoya ‘Fino de Jete’ por aplicación de 6-bencilaminopurina

The cherimoya (Annona cherimola Mill.) fruit is climacteric and has a very short postharvest life; the symptoms of senescence include peel browning and fruit softening. The objective of this research was to evaluate the effect of application of 6-benzylaminopurine (BAP) in the postharvest life of cherimoya fruit ‘Fino de Jete’. Fruits were randomly selected from the middle and basal part of six trees. BAP was applied at 1.0 mM or 0 mM in every of two dates, that is 8 or 15 days before harvest (DAC). After harvest, fruits were transported for 1.5 h and stored in two different temperatures, refrigerated (TR) (6 °C) or room temperature (TA) (16 ± 2 °C). Every third day, from 1 to 15 day after harvest (DDC), they were analyzed in relation to weight loss, color L*, a* and b*, and fruit firmness and deformation. In TA, the fruits treated with 1 mM BAP in both, 8 or 15 DAC retained peel color L* over 35% (ρ ≤ 0.05) in relation to control.

Analysis of the effect of high hydrostatic pressure treatment and enterocin AS-48 addition on the bacterial communities of cherimoya pulp

In the present study, pulp obtained from cherimoya pulp (Annona cherimola) was inoculated with epiphytic microbiota collected from cherimoya fruits, and supplemented or not with the circular bacteriocin enterocin AS-48 (50μg/g) and then packed under vacuum. Samples supplemented or not with enterocin were treated by high hydrostatic pressure (600MPa, 8min) and then stored at 5°C for 30days. The single AS-48 treatment only delayed microbial growth non-significantly (p>0.05). HHP treatment reduced microbial counts by five log cycles, but it did not prevent further growth of survivors by day 7. The combined treatment (AS-48+HHP) was the most effective, keeping bacterial cell densities at ≤1.5 log CFU/g for up to 15days. 16S rRNA gene pyrosequencing analysis was done on amplicon libraries from the growth on TSA plates seeded with ten-fold dilutions of pulp suspensions and incubated at 22°C for 24h. The results obtained are limited by the experimental conditions used in the study, and only concern the bacterial fraction that was selected by the TSA and growth conditions used. Pantoea (Pantoea agglomerans, Pantoea vagans) were the operational taxonomic units (OTUs) detected at highest relative abundance in bacterial biomass grown from control samples for the first 7days of storage, followed by Enterococcus gallinarum and Leuconostoc mesenteroides during late storage. The single HHP treatment significantly reduced the relative abundance of OTUs belonging to Pantoea and strongly increased that of endosporeformers (mainly Bacillus firmus and Bacillus stratosphericus) early after treatment, although Pantoea became again the predominant OTUs during storage. Samples singly treated with enterocin AS-48 revealed a strong inhibition of E. gallinarum as well as an early decrease in the relative abundance of Pantoea and an increased relative abundance of OTUs belonging to other Gram-negative species (mainly from genera Serratia and Pseudomonas). The strong microbial inactivation achieved by the combined treatment with enterocin and HHP reduced the levels of viable cells below detectable limits at days 0 and 1, and survivors recovered on TSA at day 7 were represented in >99% by B. firmus OTU. OTUs from endosporeformers were no longer detected during prolonged incubation, displaced by Pantoea spp., Erwinia billingiae and leuconostocs. Results from the present study indicate that HHP in combination with enterocin AS-48 is more effective in preserving the microbiological quality of cherimoya pulp during storage than the single HHP treatment.

Two cold-induced family 19 glycosyl hydrolases from cherimoya (Annona cherimola) fruit: An antifungal chitinase and a cold-adapted chitinase

Two cold-induced chitinases were isolated and purified from the mesocarp cherimoyas (Annona cherimola Mill.) and they were characterised as acidic endochitinases with a Mr of 24.79 and 47.77kDa (AChi24 and AChi48, respectively), both family 19 glycosyl hydrolases. These purified chitinases differed significantly in their biochemical and biophysical properties. While both enzymes had similar optimal acidic pH values, AChi24 was enzymatically active and stable at alkaline pH values, as well as displaying an optimal temperature of 45°C and moderate thermostability. Kinetic studies revealed a great catalytic efficiency of AChi24 for oligomeric and polymeric substrates. Conversely, AChi48 hydrolysis showed positive co-operativity that was associated to a mixture of different functional oligomeric states through weak transient protein interactions. The rise in the AChi48 kcat at increasing enzyme concentrations provided evidence of its oligomerisation. AChi48 chitinase was active and stable in a broad acidic pH range, and while it was relatively labile as temperatures increased, with an optimal temperature of 35°C, it retained about 50% of its maximal activity from 5 to 50°C. Thermodynamic characterisation reflected the high kcat of AChi48 and the remarkably lower ΔH(‡), ΔS(‡) and ΔG(‡) values at 5°C compared to AChi24, indicating that the hydrolytic activity of AChi48 was less thermodependent. In vitro functional studies revealed that AChi24 had a strong antifungal defence potential against Botrytis cinerea, whereas they displayed no cryoprotective or antifreeze activity. Hence, based on biochemical, thermodynamic and functional data, this study demonstrates that two acidic endochitinases are induced at low temperatures in a subtropical fruit, and that one of them acts in an oligomeric cold-adapted manner.

Value Chains of Cherimoya(Annona CherimolaMill.) in a Centre of Diversity and its on-Farm Conservation Implications

This paper uses value chain analysis as a novel method to examine the conservation status of and strategies for cherimoya (Annona cherimola Mill.), an underutilized, perennial fruit species native to the Andean valleys of Ecuador, Peru and Bolivia. It was found that value chain features such as market channels, chain governance, quality performance and distribution of added value over chain actors differ significantly between cherimoya fruits that are registered by a collective trademark such as the Cumbe variety and another group of more traditionally produced and commercialized cherimoya fruits. The former is exported from its production area (Lima province in Peru) to neighboring Andean countries, is graded and selected intensively, has a higher quality perception and creates significantly more added value for both producers and traders than the other, locally produced cherimoyas whose value chain is governed less intensively. Previous studies on the genetic diversity of cherimoya in the countries of origin have stressed the necessity of conserving cherimoya germplasm in areas characterized by highly diverse (southern Ecuador and northern Peru) or rare (Bolivia) cherimoya germplasm. Although value chain development is generally considered crucial in on-farm conservation of underutilized species, the example of the Cumbe cherimoya shows that intraspecific diversity can be threatened by commercial success. Farmers who believe that quality is exclusively linked to a certain genotype have purchased Cumbe cherimoya grafts from each other, leading to genetic erosion of the local cherimoya genetic base.

Radical scavenging, antioxidant and metal chelating activities of Annona cherimola Mill. (cherimoya) peel and pulp in relation to their total phenolic and total flavonoid contents

This study aimed to evaluate the total phenolic and flavonoid content, radical scavenging activity (by DPPH and ABTS tests) and antioxidant capacity (by β-carotene bleaching test) of Annona cherimola (cherimoya) fruits cultivated in Italy for human consumption. The metal chelating activity and ferric reducing power were also determined. A. cherimola peel and pulp were characterized by a total phenolic content of 14.6 and 12.6mg chlorogenic acid equivalents/100g fresh weight, respectively. A similar trend was observed with flavonoid content. Both extracts exhibited high antioxidant activity through different mechanisms of action. In particular, peel extract demonstrated the strongest free radical scavenging activity with an IC50 value of 57.7μg/mL. The same extract was more effective in preventing β-carotene oxidation (IC50 value of 63.5μg/mL after 60min) and showed higher chelating ability (IC50 value of 79.6μg/mL) than pulp extract. This work demonstrated the high quality of cherimoya fruits cultivated in Italy, and recommends the peel of this fruit product that may be of interest from a functional point of view as a major source of natural antioxidants.

Monitoring the pollution risk and water use in orchard terraces with mango and cherimoya trees by drainage lysimeters

Agricultural nonpoint-source pollution is the leading cause of water-quality degeneration of rivers and groundwater. In this context, the coast of Granada province (SE Spain) is economically an important area for the subtropical fruit cultivation. This intensively irrigated agriculture often uses excessive fertilizers, resulting to water pollution. Therefore, a 2-year experiment was conducted using drainage lysimeters to determine the potential risk of nutrient pollution in mango (Mangifera indica L. cv. Osteen) and cherimoya (Annona cherimola Mill. cv. Fino de Jete) orchards. These lysimeters were used to estimate the nutrient budgeting for each crop. NO3-N, NH4-N, PO4-P and K losses according to lysimeters were, respectively, 55.1, 12.4, 3.7, and 0.6 for mango and 61.8, 17.8, 4.9, and 0.5 kg ha−1 yr−1, for cherimoya. NO3, concentrations in the leachates ranged from 1.8 to 44.3 mg L−1, and from 23.0 to 51.0 mg L−1, for mango and cherimoya, respectively, in some cases exceeding the limits for safe drinking water. PO4 also exceeded the permitted concentrations related to eutrophication of water, ranging from 0.07 to 0.5 mg L−1 and from 0.12 to 0.68 mg L−1 from mango and cherimoya lysimeters, respectively. With respect to the nutrient balance, N, P, and K removed by cherimoya fruits was 76.4, 5.5, and 22.6 kg ha−1 yr−1, and for mango fruits 30.2, 3.3 and 27.8 kg ha−1 yr−1, respectively. Nutrient losses in the leachates were surprisingly low, considering total N, P, and K applied during the year, in mango lysimeters 3.8, 0.11, and 12.6%, and in cherimoya lysimeters 7.7, 0.23 and 16.0%, respectively, indicating a potential soil accumulation and eventual loss risk, especially during torrential rains. Crop coefficient (Kc) values of mango trees varied within ranges of 0.35–0.67, 0.55–0.89, and 0.39–0.80 at flowering, fruit set, and fruit growth, respectively. Kc values for cherimoya trees had ranges of 0.58–0.67, 0.61–0.68, and 0.43–0.62 at flowering, fruit set and fruit growth, respectively. In this study, the Kc values of mango and cherimoya were significantly correlated to julian days. Therefore, the estimated WUE in the mango and cherimoya orchards reached 21.2 and 14.0 kg ha−1 mm−1, respectively. Thus, this study highlights the urgency to establish the optimal use of fertilizers and irrigation water with respect to crop requirements, to preserve surface-water and groundwater quality, thereby achieving more sustainable agriculture in orchard terraces.

A cryoprotective and cold-adapted 1,3-β-endoglucanase from cherimoya ( Annona cherimola) fruit

A 1,3-β-glucanase with potent cryoprotective activity was purified to homogeneity from the mesocarp of CO 2-treated cherimoya fruit ( Annona cherimola Mill.) stored at low temperature using anion exchange and chromatofocusing chromatography. This protein was characterized as a glycosylated endo-1,3-β-glucanase with a M r of 22.07 kDa and a p I of 5.25. The hydrolase was active and stable in a broad acidic pH range and it exhibited maximum activity at pH 5.0. It had a low optimum temperature of 35 °C and it retained 40% maximum activity at 5 °C. The purified 1,3-β-glucanase was relatively heat unstable and its activity declined progressively at temperatures above 50 °C. Kinetic studies revealed low k cat (3.10 ± 0.04 s −1) and K m (0.32 ± 0.03 mg ml −1) values, reflecting the intermediate efficiency of the protein in hydrolyzing laminarin. Moreover, a thermodynamic characterization revealed that the purified enzyme displayed a high k cat at both 37 and 5 °C, and a low E a (6.99 kJ mol −1) within this range of temperatures. In vitro functional studies indicated that the purified 1,3-β-glucanase had no inhibitory effects on Botrytis cinerea hyphal growth and no antifreeze activity, as determined by thermal hysteresis analysis using differential scanning calorimetry. However, a strong cryoprotective activity was observed against freeze–thaw inactivation of lactate dehydrogenase. Indeed, the PD 50 was 8.7 μg ml −1 (394 nM), 9.2-fold higher (3.1 on a molar basis) than that of the cryoprotective protein BSA. Together with the observed accumulation of glycine-betaine in CO 2-treated cherimoya tissues, these results suggest that 1,3-β-glucanase could be functionally implicated in low temperature-defense mechanism activated by CO 2.