Preservation of mango quality by using functional chitosan-lactoperoxidase systems coatings

Mohamed Ciss a,b,*, Jessica Polidori a, Didier Montet a, Grard Loiseau a,Marie Nolle Ducamp-Collin a

aCIRAD, UMR Qualisud, 73 rue Jean Franois Breton, 34398 Montpellier Cedex 5, FrancebUniversity Peleforo Gon Coulibaly Korhogo, Cote dIvoire

A R T I C L E I N F O

Article history:Received 20 June 2014Received in revised form 25 October 2014Accepted 3 November 2014

Keywords:ChitosanLactoperoxidase systemEdible coatingsMango

A B S T R A C T

Influence of chitosan coating with or without the active antimicrobial lactoperoxidase system wasstudied on postharvest mangoes. Mangoes were treated with three concentrations of chitosan (0.5; 1;1.5%) containing or not lactoperoxidase with or without iodine as a second electron donor. Coatingscontaining 1 and 1.5% chitosan incorporated with lactoperoxidase system efficiently inhibited fungalproliferation and delayed mango ripening. Iodine did not influence antifungal activity. Ripeningparameters (firmness, respiration, weight loss and color) were not influenced by the lactoperoxidasesystem, butweremore influenced by chitosan concentration. Chitosan coating alone reducedweight loss,and delayed the decline in firmness and respiration rate. It exhibited a beneficial effect on the contents oftotal soluble solids (TSS), ascorbic acid, total acidity (TA) and pH.

2014 Elsevier B.V. All rights reserved.

1. Introduction

Developing countries experience significant postharvest lossesof fruit and vegetables, and among these agricultural products,mango is a dominant tropical fruit variety (FAO, 2003). However,mangoes face problems in storage due to various diseases causedby fungi and bacteria. The control of these diseases has becomedifficult because of strain resistance to fungicides and increasinglyrigorous regulations. These regulations on the use of fungicidehave reduced the ability to develop control strategies based onchemicals (Johnson and Sangchote, 1994). An alternative to thisproblem could be the use of natural compounds that have a broadantimicrobial spectrum.

The lactoperoxidase system (LPOS) has been described as anexcellent system for fighting pathogenic microorganisms as it hasa broad antimicrobial spectrum. This enzyme system has shown abactericidal effect on Gram-negative bacteria and a bacteriostaticeffect on Gram-positive bacteria (Seacheol et al., 2005). Inaddition, it has antifungal (Jacob et al., 2000) and antiviral activity(Pakkanen and Aalto, 1997; Seifu et al., 2005). This systemgenerates intermediate antimicrobial products such as

hypothiocyanite (OSCN) and hypothiocyanate acid (HOSCN).These highly reactive products inhibit microorganisms byoxidation of the sulfhydryl groups of microbial enzymes(Martnez-Camacho et al., 2010). Presence of iodine in additionto thiocyanate increases the fungicidal and bactericidal effectagainst microbes such as Candida albicans,Escherichia coli andStaphylococcus aureus (Bosch et al., 2000). LPOS incorporated intomatrix polymers by immobilization, absorption, or trapping hasbeen operating in the pharmaceutical and food areas. Theeffectiveness of incorporation of the LPOS into whey proteins(Min et al., 2005; Min and Krochta, 2005) and alginate films (Fatihet al., 2009) has been demonstrated. Chitosan has multiplebiological and chemical properties. Amino and hydroxyl groups ofthe linear polyglucosamine chain are very reactive, and conse-quently it is amenable to chemical modification. Dissolved in anacid solution, chitosan has a high positive charge on NH3+ groupswhich can form an aggregate with polyanions. This characteristicprovides excellent ionic properties to chitosan gels which givethem remarkable affinity to proteins. In addition, chitosan hasantimicrobial properties and can protect fruit against fungaldeterioration (Atia et al., 2005; Photchanachai et al., 2006).Chitosan could be used to stabilize LPOS antimicrobial activity fora long time, and it may also delay the ripening of fruit.

The objective of this study, therefore was to enhance theeffectiveness of LPOS linked to chitosan and thereby extend thepostharvest preservation of mangoes.

* Corresponding author at: BP 1328 Korhogo, Cote dIvoire.Tel.: +33 4 67615498/225 07082215; fax: +33 4 67615515.

E-mail address: cismorad@yahoo.fr (M. Ciss).

http://dx.doi.org/10.1016/j.postharvbio.2014.11.0030925-5214/ 2014 Elsevier B.V. All rights reserved.

Postharvest Biology and Technology 101 (2015) 1014

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2. Materials and methods

Experiments were performed on mangoes (Mangifera indica L.cv. Kent) imported from Brazil, and purchased in a localsupermarket in Montpellier France. Selected mature green fruitwere uniform in size (59130g), with good quality and were freefrom injury or disease.

LPOS was composed of lactoperoxidase (LPO; 140U/mg,Bioserae, France), glucose oxidase (GO; 158.9U/mg, SigmaAldrich); D (+) glucose (Glu SigmaAldrich), potassium thiocyanate(KSCN, Bioserae, France), with or without potassium iodide(KI, Fluka). Chitosan (>90% DDA viscosity 5002000 cps) wasobtained from France Chitin (Marseille, France). Glycerol, used as aplasticizer to improve coating flexibility, was purchased fromFisher Scientific Inc. (Fair Lawn, NJ). Strains of Colletotrichumgloeosporioides, Phomopsis sp. RP257, Pestalotiopsis sp. andLasiodiplodia Theobromae ngr 05A were isolated and identifiedby CIRAD (Montpellier-France).

2.1. Preparation of solution of LPOS

The weight ratios of the LPOS components were 0.35, 1.00, 1.09,2.17 and 108.70 respectively for LPO, GO, Glu KSCN, and KI.The composition was adapted from Min and Krochta (2005). Thecomponents were dissolved separately in 50mL phosphate buffer(pH 6.2) and 15.5mg of LPO was added. LPOS solution wasincubated at 232 C for 24h with shaking at 160 RPM using awater bath shaker (Julabo SW 20 Silab, France) to increase theantimicrobial activity of LPOS (Bosch et al., 2000; Min et al., 2007).Two solutions of the enzyme system were prepared, one withiodine (LPOSI) and one without (LPOS).

2.2. Preparation of chitosan film-forming solutions

Chitosan solutions were prepared by dissolving chitosan flakes(0.5, 1 and 1.5 g) in distilled water (80mL) containing 0.7mL oflactic acid (Sigma) under agitation using a magnetic stirrer,incubated over night at room temperature (22 C). The pH of thesolution was adjusted to 5.5 with 0.46MK2HPO4 (SigmaAldrich)and the solution was made up to 100mL with distilled water.Glycerol (25% p/p of chitosan) was added and the solution wasstirred at ambient temperature for 30min.

2.3. Antimicrobial tests

Fruit were sterilized by washing with chlorinated water (1%)and rinsing with distilled water. Identical lesions (diameter 1mmand depth 3mm) were performed on the two opposite sides of thefruit with sterile nails. Fruit were then inoculated individually byimmersion for 1min in the microbial solution (105 spore/mL ofselected mould) and left overnight at room temperature. Theywere dipped into the coating solution and then stored at 18 C and60% RH. Percentages of inhibition of microorganisms by thedifferent coatings were calculated by comparing with the control(uncoated mango), when the diameter of the lesions of the latterexceeded 1 cm. Percentages of inhibition (%) = 1 (DS/DC)100,where DS is the diameter of the lesion zone in the coated mangoand DC is the diameter of lesion in the control (uncoated mango)(Martnez-Camacho et al., 2010).

2.4. Respiration rate

Respiratory rate (RR) was determined by individually placingeach fruit in a 3 L glass jar hermetically closed for 3h. Then 0.5mLof gas was withdrawn with a syringe and analyzed to determinethe % of CO2 and O2 by gas chromatography (GC 800, CE

instrument, Italy) for oxygen and GC 1000, Dani, Italy, for carbondioxide). The respiratory rate was expressed in mmol kg1 h1 innormal conditions of temperature and pressure.

2.5. Evaluation of the quality of mangoes

Weight loss was determined by daily weighing mangoes with abalance (Precisa, Switzerland). Weight loss was expressed as apercentage of initial weight.

Firmness was determined using a TA XT2 texture analyzer(Instron Co., USA), calibrated at 5 kg and equipped with a 2mmdiameter probe. Initial grip separation was 30mm with a strokespeed of 1mm/s.

The color of the fruit skin was measured using a Minoltachromameter (Chroma meter CR 400, Japan). Three determina-tions were performed on different sides of each fruit and theaverage represented the color value. The results were determinedin the color space L*, a* and b*.

Total soluble solids (TSS) concentration were measured with adigital refractometer Atago PR-101 (Atago Co., Ltd., Tokyo, Japan) at20 C and expressed as % of dry matter.

Thirty (30) grams of mango pulp were homogenized in 150mLof distilled water using a blender for 2min and then filtered. ThepH was determined with a pH meter (Kyle, USA). Total acidity (TA)was determined on 10mL of homogenate pulp by automatictitration with 0.1N NaOH up to pH 8.1. The results were expressedas g citric acid equivalent per 100g fresh weight. Ascorbic acidcontent was determined by colorimetry using 2,6-dichloropheno-lindorhenol titration (AOAC, 1984).

2.6. Statistical analysis

Experimental data were subjected to ANOVA analysis usingStatistica 7. The overall least significant differences (Student'sprocedure, p1 cm) after seven days of storagewhereas those treated with Colletotrichum gloeosporiodes strainsand L. diplodia showed signs of fungal decay after fourteen days.

[(Fig._1)TD$FIG]

Fig. 1. Antifungal activity of different coatings against pathogenic strains on Kentmango fruit. Coatings are defined in Section 2.

M. Ciss et al. / Postharvest Biology and Technology 101 (2015) 1014 11

The rapid ability of Phomopsis to infect mangoes indicated that itwas the most virulent of the strains tested.

Fig. 1 shows different sensitivities of strains to differentcoatings applied on the mangoes. The concentration of chitosanin the coating solution and the presence of the enzyme systemaffected the fungal decay of the fruit. The percentage of straininhibition was improved with the increase of chitosan concentra-tion, and it became higher when the LPOS system was added. Theinhibitory action of chitosan alone has already been demonstratedin several studies. These studies reported that the antifungal effectof chitosan was dependent on concentration (El Ghaouth et al.,1992; Jiang and Li, 2001; Liu et al., 2007). Chitosanwith its positivecharges interacts with negatively chargedmembranes of the cell toalter cell permeability.

In all the cases, the inhibition by the coatings was improved bythe LPOS. Some strains that showed a resistance to chitosanbecame more sensitive to LPOS. Phomopsis was inhibited 58% bychitosan, 1% alone and in the presence of LPOS, the inhibitionreached about 100%. These results showed that there was asynergistic effect of chitosan and LPOS.

Inhibitory effects increased with the incorporation of LPOS orLPOSI in chitosan at 1 or 1.5%. The synergistic effect between theLPOS with chitosan against C. gloeosporioides strains and L. diplodiahas already been demonstrated by Ciss et al. (2013). They revealedthat this combination was more effective with chitosan at 1 and1.5%.

No significant difference was observed during comparison ofthe effects of inhibition of LPOSwith andwithout iodine (LPOS andLPOSI) at the same concentration of chitosan. Presence of iodine inthe enzyme system (LPOSI) did not influence significantly theantifungal activity of LPOS. This result confirmed those found byCiss et al. (2013) on mango phytopathogenic strains in vitro.Effectiveness of the presence of iodine in LPOS has also beenstudied also by Bosch et al. (2000) who reported that addition ofiodine with thiocyanate increased the fungicidal and bactericidaleffect against C. albicans, E. coli and S. aureus while Pseudomonasaeruginosa showed the same inhibition from the lactoperoxidasesystem with or without iodide.

3.2. Respiration rate

Table 1 shows O2 consumption and CO2 produced fromuncoated and coated mangoes with 1 and 1.5% of chitosanincorporated with LPOS or LPOSI. Significant differences (p 0.05).

12 M. Ciss et al. / Postharvest Biology and Technology 101 (2015) 1014

film-forming solution did not have any significant effect onweightloss reduction. Thumula (2006) showed also that the presence oflysozyme in chitosan coatings did not influence the loss of weightof tomatoes.

3.4. Changes in color

Color of mango skins is an important selection criterion forbuyers. It can give an indication of the state of fruit ripening. Asshown in Fig 2, noticeable changes in the skin color occurredduring storage. Uncoated mangoes lost their green color (a* > 0)unlike coated fruit that maintained this color (a* 0.05).

[(Fig._2)TD$FIG]

Fig. 2. Color properties of Kent mangoes treated with different coatingformulations. Coatings are defined in Section 2.

[(Fig._3)TD$FIG]

Fig. 3. Firmness changes in Kent mangoes treated with different coatingformulations. Coatings are defined in Section 2.

M. Ciss et al. / Postharvest Biology and Technology 101 (2015) 1014 13

4. Conclusion

This study demonstrated the effectiveness of chitosan coatingcontaining LPOS in postharvest conservation of mangoes. Chitosanhas antimicrobial activity which was been strengthened by theLPOS. A chitosan concentration at 1% containing LPOS wassufficiently effective against microbial contamination and enableda delay in fruit ripeningwithout altering quality. If chitosan coatinghad an effect on the physico-chemical properties, the presence ofthe LPOS did not affect those parameters. Use of chitosanLPOScould thus be an effective approach in the preservation of tropicalfruit, an alternative in limiting synthetic pesticide use.

References

Ali, A., Muhammad,M.T.M., Sijam, K., Siddiqui, Y., 2011. Effect of chitosan coatings onthe physicochemical characteristics of Eksotika II papaya (Carica papaya L.) fruitduring cold storage. Food Chem. 124, 620626.

AOAC, 1984. Official methods of analysis of the association of official analyticalchemists (14th ed.). Washington, DC.

Atia, M.M., Buchenauer, H., Aly, A.Z., Abou-Zaid, M.I., 2005. Antifungal activity ofchitosan against Phytophthora infestans and activation of defence mechanismsin tomato to late blight. Biol. Agric. Hortic. 23, 175197.

Bosch, E.H., Van Doorne, H., De Vries, S., 2000. The lactoperoxidase system: theinfluence of iodide and the chemical and antimicrobial stability over the periodof about 18 months. J. Appl. Microbiol. 89, 215224.

Ciss, M., Clementine, K.A., Montet, D., Loiseau, G., Ducamp-Collin, M.N., 2013.Antimicrobial and physical properties of edible chitosan films enhanced bylactoperoxidase system. Food Hydrocol. 30, 576580.

Ciss,M.,Montet, D., Tapia,M.S., Loiseau, G., Ducamp-Collin,M.N., 2012. Influence oftemperature and relative humidity on the immobilized lactoperoxidase systemin a functional chitosan film. Food Hydrocol. 28, 361366.

Deng, Y., Wu, Y., Li, Y., 2006. Physiological responses and quality attributes ofKyohograpes to controlled atmosphere storage. Food Sci. Technol. 39, 584590.

El Ghaouth, A., Ponnampalam, R., Castaigne, F., Arul, J., 1992. Chitosan coating toextend the storage life of tomatoes. Hort. Sci. 27, 10161018.

FAO, 2003. Committee on commodity problems. Puerto de la Cruz Spain. ftp://ftp.fao.org/unfao/bodies/ccp/ba-tf/04/j0603e.pdf.

Fatih, Y.G., Yener, F.Y., Yemenicioglu, A., 2009. Antimicrobial activity oflactoperoxidase system incorporated into cross-linked alginatefilms. J. Food Sci.74, 7379.

Hagenmaier, R.D., 2005. A comparison of ethane: ethylene and CO2 peel permeancefor fruit with different coatings. Postharvest Biol. Technol. 37, 5664.

Jacob, B.M., Antony, E., Sreekumar, B., Haridas, M., 2000. Thiocyanate mediatedantifungal and antibacterial property of goatmilk lactoperoxidase. Life Sci. 66,24332439.

Jiang, Y., Li, Y., 2001. Effects of chitosan coating on postharvest life and quality oflongan fruit. Food Chem. 73, 139143.

Johnson, G.I., Sangchote, S., 1994. Control of postharvest diseases of tropical fruits:challenges for the 21st century. In: Champ, B., Highley, E., Johnson, G. (Eds.),Postharvest Handling of Tropical Fruits. Australian Center for InternationalAgricultural Research, Canberra, pp. 140167.

Liu, J., Tian, S., Meng, X., Xu, Y., 2007. Effects of chitosan on control of postharvestdiseases and physiological responses of tomato fruit. Postharvest Biol. Technol.44, 300306.

Martnez-Camacho, A.P., Cortez-Rocha, M.O., Ezquerra-Brauer, J., M, Graciano-Verdugo, A.Z., Rodriguez-Flix, F., Castillo-Ortega, M.M., Ypiz-Gmez, M.S.,Plascencia-Jatomea, M., 2010. Chitosan composite films: thermal, structural,mechanical and antifungal properties. Carbohydr. Polym. 82, 305315.

Min, M., Harris, L., Krochta, J., 2005. Antimicrobial effects of lactoferrin, lysozyme,and the lactoperoxidase system and ediblewhey proteinfilms incorporating thelactoperoxidase system against Salmonella enterica and Escherichia coliO157:H7.J. Food Sci. 70, 332338.

Min, S., Krochta, J.M., 2005. Inhibition of Penicillium commune by edible wheyprotein films incorporating lactoferrin, lactoferrin hydrolysate, andlactoperoxidase systems. J. Food Protect. 70, 8794.

Min, S., Krochta, J.M., Rumsey, T.R., 2007. Diffusion of thiocyanate andhypothiocyanite in whey protein films incorporating the lactoperoxidasesystem. J. Food Eng. 80, 11161124.

zden, ., Bayindirli, L., 2002. Effects of combinational use of controlledatmosphere: cold storage and edible coating applications on shelf life andquality attributes of green peppers. Eur. Food Res. Technol. 214, 320326.

Pakkanen, R., Aalto, J., 1997. Growth factors and antimicrobial factors of bovinecolostrums. Int. Dairy J. 7, 285297.

Paull, R., Chen, N., Goo, T., 1989. Waxing and plastic wraps influence water loss frompapaya fruit during storage and ripening. J. Amer. Soc. Hort. Sci. 114, 937942.

Photchanachai Singkaew, S.J., Thamthong, J., 2006. Effects of chitosan seedtreatment on Colletotrichum sp. and seedling growth of chili cv. Jinda. ActaHortic. 585590.

Seacheol, M., Linda, J.H., John, M.K., 2005. Antimicrobial Effects of Lactoferrin,Lysozyme, and the Lactoperoxidase System and Edible Whey Protein FilmsIncorporating the Lactoperoxidase System against Salmonella enterica andEscherichia coli O157:H7. Food Microbiol. Safety 70, 332338.

Seifu, E., Buys, E.M., Donkin, E.F., 2005. Significance of the lactoperoxidase system inthe dairy industry and its potential applications: a review. Trends Food Sci.Technol. 16, 137154.

Tasdelen, ., Bayindirli, L., 1998. Controlled atmosphere storage and edible coatingeffects on storage life and quality of tomatoes. J. Food Process. Preserv. 22,303320.

Thumula, P., 2006. Studies On Storage Behaviour of Tomatoes CoatedWith Chitosan-Lysozyme Films. Department of Bioresource Engineering, McGill University,Montreal.

Vsconez, M.B., Flores, S.K., Campos, C.A., Alvarado, J., Gerschenson, L., 2009.Antimicrobial activity and physical properties of chitosantapioca starch basededible films and coatings. Food Res. Int. 42, 762769.

Table 3Chemical composition of Kent mangoes.

pH Titrable acidity (g/citric acid/100 g of pulp) T.S.S (%) ascorbic acid (mg/100ml)

Reference 3.61b0.11 1.35a0.03 12.56a0.07 29.36a 0.35Uncoated 4.88a00 0.29b 0.02 14.875a0.03 5.84b0.141% Chit 4.195b0.12 0.58c 0.03 14.65a 0.07 25.48c5.21% ChitLPOS 4.18b0.49 0.69cd 0.05 13.425a0.1 23.04c2.61% ChitLPOSI 3.83b0.20 0.76cd 0.13 13a1.13 23.64c2.091,5% Chit 4.07b0.04 0.8 d 0.01 13,65a0.78 23.54c0.51.5% ChitLPOS 3.82b0.02 0.80d 0.23 12.55a0.35 25.94c3.451.5% ChitLPOSI 4.06b0.01 0.68cd 0.09 12.8a0.42 24.80c4.56

Means are averaged values of three trials. Each trial contained three replicates per treatment. Values within a column with the same letter are not significantly different(p> 0.05). Reference is value before storage.

14 M. Ciss et al. / Postharvest Biology and Technology 101 (2015) 1014

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Preservation of mango quality by using functional chitosan-lactoperoxidase systems coatings1 Introduction2 Materials and methods2.1 Preparation of solution of LPOS2.2 Preparation of chitosan film-forming solutions2.3 Antimicrobial tests2.4 Respiration rate2.5 Evaluation of the quality of mangoes2.6 Statistical analysis

3 Results and discussion3.1 Antifungal activity of different coatings3.2 Respiration rate3.3 Weight loss of fruit during storage3.4 Changes in color3.5 Firmness3.6 Chemical composition change in fruit4 Conclusion

References