Preparation of antimicrobial agar/banana powder blend films reinforced with silver nanoparticles
Graphical abstract
Introduction
Recently, biopolymers from various natural resources such as starch, cellulose, agar, alginate, carrageenan, gelatin, soy protein, whey protein, and wheat gluten have been used as eco-friendly packaging materials for the substitute of non-biodegradable petroleum-based plastic based packaging materials (Shankar et al., 2015a, Shankar et al., 2015b, Giménez et al., 2013). As one of such biopolymers, agar has been widely used for the preparation of biodegradable packaging films due to its good film forming property with abundance, renewability, and biocompatibility (Wang & Rhim, 2015). Agar is a hydrophilic polysaccharide extracted from the Gelidiaceae and Gracilariaceae families of seaweeds and mainly composed of alternating repeating units of d-galactose and 3, 6-anhydro-β-galactopyranose (Gehrke, 1993, Tako et al., 1999). High compatibility with other biopolymers of agar with good film-forming properties made it as a good candidate for blending with other biopolymers to enhance the properties of the blended films (El-Hefian et al., 2012, Varshney, 2007, Wang and Rhim, 2015). Various materials, such as protein (Wang & Rhim, 2015), nano-clay (Kanmani & Rhim, 2014a), nanocellulose (Shankar & Rhim, 2016), grapefruit seed extract (Kanmani & Rhim, 2014b), lignin (Shankar et al., 2015b), and metallic nanoparticles (Shankar & Rhim, 2015) have been blended with agar to improve the mechanical, water resistance, and functional properties of the films. However, to the best of our knowledge, the report on banana powder as a reinforcing agent in agar biopolymer is not available in the literature so far.
Banana, Musa sapientum Linn. is a tropical fruit which contains a high amount of polysaccharide (starch 61–76% dry basis), proteins, and fat (Waliszewski, Aparicio, Bello, & Monroy, 2003). In addition, at the green stage, banana is a major source of macro-elements and it contains health-beneficial ingredients such as resistant starch and dietary fibers that have the potential to increase the hydrophobicity of polymers (Anyasi et al., 2013, Pelissari et al., 2013). Moreover, the polyphenolic compounds included in banana are expected to enhance the functional properties, to secure the food safety, and to extend the shelf-life of food (Pereira and Maraschin, 2015, Sothornvit and Pitak, 2007, Waliszewski et al., 2003). Banana peel extract has been used for the synthesis of silver nanoparticles for the test of their antimicrobial and free radical scavenging activities (Kokila, Ramesh, & Geetha, 2005).
Bionanocomposite packaging materials with antibacterial function is believed to be one of the promising active packaging materials to extend the shelf-life of food, maintain the food safety, quality, and to improve the storage period by destroying or inhibiting the food pathogenic microorganisms (Kanmani and Rhim, 2014a, Shankar et al., 2014a). Silver nanoparticles (AgNPs) have been most widely used for the preparation of nanocomposite in the food packaging and biomedical applications due to their high surface area, unique optical, magnetic, electric, catalytic, thermal stability, and broad-spectrum of antimicrobial properties. Instead of hazardous chemical reagents, various biopolymers such as gelatin (Kanmani & Rhim, 2014a), glucose, starch (Cheviron et al., 2014, Vigneshwaran et al., 2006), and chitosan (Huang & Yang, 2004), as well as plant extracts (Shankar et al., 2014b, Shankar et al., 2014c) have been used for the synthesis of AgNPs. Therefore, in the present study, banana powder was used as a reducing and stabilizing agent for the preparation of AgNPs.
The objectives of the present study were to prepare agar/banana powder binary blend films (A/B) and agar/banana powder blend films with AgNPs (A/B/AgNPs) and to characterize their properties for their potential use as food packaging application. Banana powder was aimed to blend with agar to improve the water barrier and functional properties such as ultraviolet (UV) screening effect, antioxidant, and antimicrobial activity of the A/B binary blend film. Banana powder is rich in carbohydrate composed of starch as the main constituent with good film-forming property (Waliszewski et al., 2003). A small amount of protein, ash, and fat presented in banana powder played an important role in the optical, physicochemical properties when used as a main or a part of the raw material to form a film (Pelissari et al., 2013). In addition, banana powder contained some phytochemicals such as tannins and terpenoids (β-carotene) as phytochemicals (Anyasi et al., 2013). Tannins are one of a polyphenolic compound found in unripe fruit that can provide antioxidant activity and help in reducing metal ions to nanoparticles (Pereira & Maraschin, 2015).
Section snippets
Materials
Green banana (M. sapientum Linn.) at the age of 112–116 days after petal fall was obtained from the orchard of Kasetsart University, Khamphaengsaen Campus, Nakhonpathom, Thailand. Food grade agar was purchased from Yun Doo Co., Ltd. (Uijeongbu, Gyeonggi-do, Korea). Glycerol was procured from Daejung Chemicals & Metals Co., Ltd. (Siheung, Gyeonggi-do, Korea). 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) was purchased from Sigma–Aldrich Chemical Co. (St. Louis, MO, USA). Tryptic soy broth (TSB) and
Optical properties of films
Apparently all the films formed were flexible and free-standing. Surface color and transmittance of the films were greatly influenced by blending with banana powder as shown in Table 1. The neat agar film (A4/B0) was clear and transparent with a high lightness value of 92.3. Addition of banana powder decreased Hunter L-value and increased Hunter a- and b-values, in which the lightness (Hunter L-value) decreased monotonously and the redness (a-value) increased quadratically with the increase in
Conclusion
Well compatible agar/banana powder blend films with and without AgNPs inclusion were prepared to improve the water sensitivity and functional properties such as antioxidant and antimicrobial activity of agar film. The blending of agar with banana powder with different mixing ratio and incorporation of AgNPs significantly influenced the film properties such as color, transmittance, mechanical, moisture content, solubility, water contact angle, water vapor permeability, thermal stability,
Acknowledgments
This research was supported by the Thailand Research Fund through the Royal Golden Jubilee Ph.D. Program (Grant No. PHD/0265/2552), and the Agriculture Research Center (ARC 710003) program of the Ministry of Agriculture, Food and Rural Affairs, Republic of Korea.
References (43)
- et al.
Edible films produced with gelatin and casein crosslinked with transglutaminase
Food Research International
(2006) - et al.
Beta-carotene, lycopene, and alpha-tocopherol contents of selected Thai fruits
Food Chemistry
(2009) - et al.
Green synthesis of colloid silver nanoparticles and resulting biodegradable starch/silver nanocomposites
Carbohydrate Polymers
(2014) - et al.
Measurement error in water vapor permeability of high permeable, hydrophilic edible film
Journal of Food Engineering
(1994) - et al.
Release of active compounds from agar and agar-gelatin films with green tea extract
Food Hydrocolloids
(2013) - et al.
Influence of beet flour on the relationship surface-properties of edible and intelligent films made from native and modified plantain flour
Food Hydrocolloids
(2016) - et al.
Synthesis of polysaccharide-stabilized gold and silver nanoparticles: a green method
Carbohydrate Research
(2004) - et al.
Physical, mechanical and antimicrobial properties of gelatin based active nanocomposite films containing AgNPs and nanoclay
Food Hydrocolloids
(2014) - et al.
Antimicrobial and physical-mechanical properties of agar-based films incorporated with grapefruit seed extract
Carbohydrate Polymers
(2014) - et al.
Antimicrobial effects of silver nanoparticles
Nanomedicine: Nanotechnology, Biology and Medicine
(2007)
Antioxidant and antimicrobial activities of various leafy herbal teas
Food Control
Comparative study on the properties of flour and starch films of plantain bananas (Musa paradisiaca)
Food Hydrocolloids
Banana (Musa spp) from peel to pulp: ethnopharmacology, source of bioactive compounds and its relevance for human health
Journal of Ethnopharmacology
Plasmonic properties of silver in polymer
Materials Science Engineer: B
Characterization of bionanocomposite films prepared with agar and paper-mulberry pulp nanocellulose
Carbohydrate Polymers
Mechanical and water barrier properties of agar/κ-carrageenan/konjac glucomannan ternary blend biohydrogel films
Carbohydrate Polymers
The effect of reducing agent concentrations and temperature on characteristics and antimicrobial activity of silver nanoparticles
Materials Letters
Synthesis, characterization, in vitro biocompatibility, and antimicrobial activity of gold, silver and gold silver alloy nanoparticles prepared from Lansium domesticum fruit peel extract
Materials Letters
Effect of lignin on water vapor barrier, mechanical, and structural properties of agar/lignin composite films
International Journal of Biological Macromolecules
Amino acid mediated synthesis of silver nanoparticles and preparation of antimicrobial agar/silver nanoparticles composite films
Carbohydrate Polymers
Preparation of nanocellulose from micro-crystalline cellulose: the effect on the performance and properties of agar-based composite films
Carbohydrate Polymers
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