• Applied Microscopy
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• v.42 no.2
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• pp.95-103
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• 2012

The cell surface sculpture of the plant epidermis has received great interest recently. It has also been an active area of research, as the biological microstructures of the surface, such as papillae and waxes, exhibit several unique properties, including self-cleaning character; namely the "Lotus effect" first described in the leaves of the lotus, Nelumbo nucifera. The Lotus effect is the phenomenon in which the super-hydrophobic and water-repellent nature of lotus leaves allow water drops to run off easily on the surface in a rolling and sliding motion thereby facilitating the removal of dirt particles. It is well-known that surface roughness on the micro- and nanoscale is a primary characteristic allowing for the Lotus effect. This effect is common among plants and is of great technological importance, since it can be applied industrially in numerous fields. In the present study, Nelumbo nucifera leaf and stem epidermal surfaces have been examined with a focus on the features of papillae and wax crystalloids. Both young and mature Nelumbo nucifera leaf epidermis demonstrated the Lotus effect on their entire epidermal surface. The central area of the upper epidermis, in particular, formed extremely papillose surfaces, with an additional wax layer, enabling greater water repellency. Despite the presence of wax crystalloids, epidermal surfaces of the lower leaf and stem lacking papillae, were much more easily wetted.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.340-347
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• 2008

This study was conducted to develop a recipe for a nutritional cookie with lotus root powder that had the optimal composition of ingredients and texture resulting in high preference by all age groups. Wheat flour was partially substituted with lotus root powder to reduce its content. Response Surface Methodology was used to analyze the measured results, which showed 16 experimental points including 2 replicates for lotus root powder, sugar and butter. The compositional and functional properties were measured, and these values were applied to a mathematical model. A canonical form and perturbation plot showed the influence of each ingredient on the final mixture product. The sensory evaluation results showed significant values in color (p<0.01), texture (p<0.05) and overall quality (p<0.05). As a result, the optimal sensory ratio was determined to be 22.59 g of lotus root powder, and 53.08 g of sugar for every 120 g of butter.

• Natural Product Sciences
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• v.25 no.1
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• pp.44-48
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• 2019

Nelumbo nucifera Gaertn. (Nymphaeaceae) is commonly called lotus and its leaves are widely been used as functional ingredients due to its antioxidant activity. For maximum efficacy, optimized extraction condition was established using response surface methodology. The high F-values, low p-values and insignificant p-value for lack-of-fit supported the fitness of the model and yielded the second-order polynomial regression for the antioxidant activity. The optimized extract was obtained by the extraction of 1 g of lotus leaves with 40 mL of 50% MeOH at $10.0^{\circ}C$, which exerted 70.1% antioxidant activity. Close correlation between phenolic content and antioxidant activity suggested phenolic compounds as active constituents of lotus leaves. In addition, comparison of different parts of lotus demonstrated the most potent antioxidant activity of flowers, followed by leaves and roots. Taken together, these results provide useful information about lotus leaves for the development as antioxidant ingredients. In addition, flowers and roots as well as leaves are suggested as good sources for antioxidant activity.

• Journal of the Korean Society of Food Culture
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• v.29 no.3
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• pp.298-306
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• 2014

The purpose of this study was to investigate the quality characteristics of steamed bread using mixed flour containing bamboo leaf and lotus leaf powders. Properties of the steamed breads were tested by colorimeter, water activity, rheometer, SEM, and sensory tests. The L values and a values were higher in steamed bread with bamboo leaf powder. On the other hand, the b values of streamed bread with bamboo leaf powder were lower than lotus leaf powder. During storage, the hardness of steamed bread with bamboo leaf and lotus leaf powders increased control. Furthermore, steamed bread with lotus leaf powder showed hardness than bamboo leaf powder. The springiness of all steamed breads decreased with storage, and steamed breads with bamboo leaf powder showed lower values than lotus leaf powder. The cohesiveness of the control was the highest, and all samples showed significant differences each other. The gumminess of the control was higher than steamed bread with bamboo leaf and lotus leaf powders. Moreover, longer storage time yielded higher gumminess. control relatively smoother surface than that of 1% bamboo leaf powder. The steamed bread with lotus leaf powder had a rougher surface than bamboo leaf powder. sensory characteristics of steamed bread, green color of the samples with bamboo leaf powder was darker than lotus leaf powder. Leaf odor was similar throughout. Freshness of steamed bread containing 1% bamboo leaf powder the highest. The overall acceptability of consumer acceptance was the control, followed by steamed bread containing 1% lotus leaf powder.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.114-120
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• 2013

A superhydrophobic surface means that the contact angle between the solid surface and a water droplet is more than $150^{\circ}$. Materials with a superhydrophobic surface have a self-cleaning function because of the Lotus effect, in which water is not absorbed by the material but rolls off of it. If such a Lotus effect can be applied to the surface of underwater vessels, submarines, torpedos, and so on, enhanced vessels can be made based on this lubricant effect reducing the friction coefficient for the liquid. Because polymer composites can be easily applied in various nanotechniques, they are more advantageous than conventional materials like iron in terms of a superhydrophobic surface. Furthermore, a superhydrophobic surface bring enhanced anticorrosion and ecotechnology because no paint is needed on underwater vessels.

• Journal of Applied Biological Chemistry
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• v.53 no.4
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• pp.232-238
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• 2010

In order to investigate the treatment efficiency of pollutants in free water surface constructed wetlands (FWS CWs) with lotus (Nelumbo nucifera) cultivation pond, the experiment was consisted of two sites (site I and II) in Lake Juam, Korea. The sites were configured a lotus cultivation pond (with fertilizer application) - a dropwort bed - a reed bed for site I, and a lotus cultivation pond (without fertilizer application) - a dropwort bed - a reed bed for site II. Removal rate of COD in site I and II were 13.3% and 26.0%, respectively. Removal rate of total nitrogen (TN) was 29.7% for site I, and 36.3% for site II. Removal rate of total phosphorus (TP) in site I and II were 36.0% and 36.5%, respectively. COD, TN and TP in effluent from site I (with fertilizer) was higher than that in site II (without fertilizer), showing that COD, TN and TP in effluent were strongly influenced by fertilizer addition. Therefore, in order to satisfy established water-quality standards, the amount of fertilizer used in lotus cultivation showed be evaluated.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.384.2-384.2
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• 2016

Recent publications reported the self-propelled jumping of coalescing dew droplets on superhydrophobic surfaces [1-2]. We further investigated the initial growth, coalescence, and removal by self-propelled ejection of nano and microscopic water droplets on the superhydrophobic surface of lotus leaves under condensing conditions. By using a high-speed digital camera mounted on an optical microscope, we have found: (1) sub-micrometer droplets form and grow on nanoscale waxy hairs; (2) growing droplets coalesce rapidly upon contact, but never jump off the surface unless the diameter of merged droplets exceeds ${\sim}15{\mu}m$; (3) the diameter and direction of jumping droplets are very narrowly distributed, centered at $20-30{\mu}m$ and ${\sim}20$ degrees from the surface normal, respectively. We present a rationale for these observations on the basis of: (a) the hierarchically rough surface structure on nano- and micro-scales; (b) its chemical composition; and (c) the balance among competing forces of cohesion (surface tension), adhesion and gravity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5756-5762
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• 2015

This paper has studied the lotus effect of the biomimetic engineering that is inspired from the nature. The biomimetic engineering has been improved with the nanotechnology. This paper has observed the hydrophobic property of the surface of the lotus leaf by using the scanning electron microscope (SEM) and atomic force microscope (AFM). The nano-scale of the hydrophobic lotus leaves are maximized the surface tension of water. The general grass leaf has been compared with the lotus leaf through the SEM and AFM - in the viewpoint of the 2D and 3D morphology. Also, The pre-existing of the hydrophobic theory was investigated and compared with the experimental observations for the lotus leaf.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.389-390
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• 2012

In this study, we fabricate a superhydrophobic surface made of hierarchical nanostructures that combine wax crystalline structure with moth-eye structure using vacuum cluster system and measure their hydrophobicity and durability. Since the lotus effect was found, much work has been done on studying self-cleaning surface for decades. The surface of lotus leaf consists of multi-level layers of micro scale papillose epidermal cells and epicuticular wax crystalloids [1]. This hierarchical structure has superhydrophobic property because the sufficiently rough surface allows air pockets to form easily below the liquid, the so-called Cassie state, so that the relatively small area of water/solid interface makes the energetic cost associated with corresponding water/air interfaces smaller than the energy gained [2]. Various nanostructures have been reported for fabricating the self-cleaning surface but in general, they have the problem of low durability. More than two nanostructures on a surface can be integrated together to increase hydrophobicity and durability of the surface as in the lotus leaf [3,5]. As one of the bio-inspired nanostructures, we introduce a hierarchical nanostructure fabricated with a high vacuum cluster system. A hierarchical nanostructure is a combination of moth-eye structure with an average pitch of 300 nm and height of 700 nm, and the wax crystalline structure with an average width and height of 200 nm. The moth-eye structure is fabricated with deep reactive ion etching (DRIE) process. $SiO_2$ layer is initially deposited on a glass substrate using PECVD in the cluster system. Then, Au seed layer is deposited for a few second using DC sputtering process to provide stochastic mask for etching the underlying $SiO_2$ layer with ICP-RIE so that moth-eye structure can be fabricated. Additionally, n-hexatriacontane paraffin wax ($C_{36}H_{74}$) is deposited on the moth-eye structure in a thermal evaporator and self-recrystallized at $40^{\circ}C$ for 4h [4]. All of steps are conducted utilizing vacuum cluster system to minimize the contamination. The water contact angles are measured by tensiometer. The morphology of the surface is characterized using SEM and AFM and the reflectance is measured by spectrophotometer.

• Journal of the Korean Dietetic Association
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• v.26 no.1
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• pp.1-13
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• 2020

This study was undertaken to optimize preparation of sweet rice muffins using lotus (Nelumbo nucifera Gaertn) seed powder. The experimental conditions used in the preparation included lotus seed powder (X₁) and soybean oil (X₂). The muffin formulation was optimized using rheology. Lightness (P<0.01) displayed a quadratic model pattern, whereas yellowness (P<0.01) and redness (P<0.05) was presented a linear model. Texture properties significantly differed in cohesiveness (P<0.05). Evaluating the sensory characteristics of muffins, except for flavor and texture, the remaining properties of color (P<0.01), taste, overall quality, and appearance (P<0.05) were found to be significantly different. The overall quality was also affected by the proportion of lotus seed powder, rather than the amount of soybean oil. The optimal ratio for palatability of muffins was determined to be 47.80 g lotus seed powder and 95.28 g soybean oil. Taken together, our results indicate that sweet rice muffins prepared using lotus seed powder are sufficiently competitive in terms of function and quality.