• Journal of Applied Biological Chemistry
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• v.64 no.2
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• pp.121-125
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• 2021

Antioxidative, anticoagulant, and α-glucosidase inhibitory effects of 60% (v/v) ethanolic extract from lotus (Nelumbo nucifera) leaves were investigated in vitro. The yield and polyphenol content of the lotus leaves extract were 35.3±1.1% and 186.2±5.2 ㎍ gallic acid equivalents/mg, respectively. The lotus leaves extract effectively scavenged free and cation radicals, and nitrite in a concentration-dependent manner, and possessed potent reducing power. The lotus leaves extract had remarkable anticoagulant and α-glucosidase inhibitory activities as a function of the extract concentration.

• 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.

• Journal of Korean society of Dental Hygiene
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• v.14 no.1
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• pp.117-122
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• 2014

Objectives : The purpose of the study is to investigate the activities of Nelumbo nucifera leaf extracts on Streptococcus mutans, Streptococcus mitis, Streptococcus sobrinus, Porphyromonas gingivalis, Prevotella intermedia, and Treponema denticola. Methods : The inhibitory effect of lotus leaf extracts on the growth of oral bacteria was assessed in experiments with extracts from freshly harvested and pulverized lotus leaves and bacterial cultures of dental caries. Results : The results showed that N. nucifera extracts possess antimicrobial activity on all bacterial strains. The minimal inhibitory concentration (MIC) values varied from 4 mg/ml to 10 mg/ml against antimicrobial activity. The relative growth ratio (RGR) against of N. nucifera extracts were determined as 50% in concentration of 4.0 mg/ml. The extract of N. nucifera was effective in reducing on the glucosyltransferase (GTase) activity of six strains in vitro. Conclusions : Methanol extracts of lotus leaves showed antimicrobial effects on three bacterial species causing dental caries and three bacterial species causing periodontitis, as well as inhibitory effects on GTase activity.

• 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.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.363-370
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• 2017

This study investigated the chemical composition of headspace gas from white-flowered lotus (Nelumbo nucifera Gaertner). Volatile flavor compositions of headspace from white-flowered lotus (floral leaf, stamen, flower stalk, stem) were investigated through the solid-phase microextraction method using polydimethylsiloxane-divinylbenzene fiber. The headspace was directly transferred to a gas chromatography-mass spectrometry. Sixty-three volatile flavor constituents were detected in the headspace of lotus floral leaves, and undecanoic acid (7.81%) was the most abundant component. Fifty-three volatile flavor constituents were detected in the headspace of lotus stamina, and isobutylidene phthalide (7.94%) was the most abundant component. Forty-four volatile flavor constituents were detected in the headspace of lotus flower stalks, and 3-butyl dihydrophthalide (11.23%) was the most abundant component. Fifty-nine volatile flavor constituents were detected in the headspace of lotus stems, and ligustilide (16.15%) was the most abundant component. The content of phthalides was higher in the headspace of flower stalks and stems, while alcohols and acids were the predominant compounds in lotus floral leaves.

• Korean Journal of Human Ecology
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• v.21 no.2
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• pp.377-388
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• 2012

The purpose of this study was to determine the content attributes and sensory characteristics of ice cream flavored with lotus leaf and seeds (Nelumbo nucifera Gaertner). Analysis of freeze dried lotus leaf powder produced the following technical results: Freeze dried lotus leaf powder contained moisture 12.2, crude protein 5.9, crude fat 1.2, crude ash 7.0, crude fiber 13.4g/100mg; raw lotus seed powder contained moisture 65.0, crude protein 8.2, crude fat 0.3, crude ash 1.0, crude fiber 10.8g/100mg; freeze dried lotus seed powder contained moisture 14.0, crude protein 17.1, crude fat 1.9, crude ash 4.0, crude fiber 2.8g/100mg. Lotus seed was processed by 4 methods: freeze dried, roasted, freeze dried peeled inner layer, cooked cut peeled inner layer. Analysis of the color value produced the following technical results: freeze dried lotus leaf powder were L(lightness) 14.5, a(redness) 4.4, b(yellowness) 24.0; freeze dried lotus seed powder L 57.3, a 14.4, b 12.0; roasted lotus seed powder L 52.7, a 22.5, b 11.9; freeze dried lotus seed peeled inner layer L 60.0, a 1.4, b 12.3. Proportional lotus ingredients used for ice cream were 1%, 3%, 5%, 7%, 10% for lotus leaves and 1%, 3%, 5% for lotus seeds. The maximum over run ratio for lotus leaf ice cream was 45.3~56.9% at 20~25 minutes operating time. Over run was significantly decreased by increasing the contents of lotus leaf powder. A maximum over run ratio for lotus seed ice cream was 46.1~54.3% at 20~25 operating time. Over run was not significantly different based on content of lotus leaf versus lotus seed. Sensory evaluation of lotus leaf ice cream produced the following results: the highest score was for color of 4.42 and the lowest score was for sweetness of 3.30. The total mean score significantly decreased by increasing the content of lotus leaf powder. Sensory evaluation of lotus seed ice cream produced the following results: the highest score was for cooked cut peeled inner layer type and the lowest was for freeze dried type 3.86. The sensory scores were not significantly different based on the content of lotus seed. Texture was evaluated highest with a rating of 4.21 and the taste was evaluated lowest with a rating of 3.68 For whole evaluation. This study concluded that lotus leaf ice cream demonstrates relative strength in terms of color and taste, and a relative weakness in terms of over run and sweetness. Suitable content of lotus leaf ranged from 1~5%. The lotus seed processed by the cooked cut peeled inner layer method received a higher rating than dried powder for lotus seed ice cream.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.219-223
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• 2006

In this study the antimicrobial activity of the extract from leaves of lotus (Nelumbo nucifera) was evaluated in comparison with benzoic acid. The $70\%$ ethanol extract was fractionated subsequently by hexane, chloroform, ethyl acetate, butanol and water, and the antimicrobial activity of each dried fraction was tested by paper disk diffusion method. The ethyl acetate fraction exhibited strong antimicrobial activity on the five strains of food born bacteria e.g. Bacillus subtilis, Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella Typhimurium and Pseudomonas nuorescens. The antimicrobial activity of the fraction was stronger than benzoic acid and showed no appreciable difference between on $Gm^+$ and $Gm^-$ bacteria. Heat treatment of the fraction at $110^{\circ}C$ for 1 hr did not change the degree of inhibitory effect. The ethyl acetate fraction showed almost perfect growth inhibition on the tested strains at over 800 ppm.

• Korean Journal of Medicinal Crop Science
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• v.17 no.2
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• pp.133-138
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• 2009

Nelumbo nucifera (lotus) is known to be a useful medicinal plant and leaf extract contains several flavonoids and alkaloids. To analyze the effect of Nelumbo nucifera leaves extract (NNL) on the HBsAg production, we treated NNL on HepG2.2.15 cells which contain the hepatitis B viral genome and secrete surface antigen into media. NNL suppressed the production of hepatitis B surface antigen as a dose-dependent manner. To analyze the effect of NNL on HBV DNA replication, PCR analysis was performed. NNL was not affected the HBV DNA replication and HBsAg mRNA expression. To understand the effect of NNL on the production of HBsAg, we carried out the analysis of lipid-metabolizing gene expression using one-step RT-PCR. NNL reduced the gene expression of FASN and SREBP2 and increased the expression of LDLR. Triglyceride content of HepG2.2.15 cells was not decreased by treatment of NNL. This result suggests a possibility that NNL may have an effect for the inhibition of hepatitis B surface antigen by modulation of lipid and cholesterol metabolism.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.771-779
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• 2017

The purpose of this study was to investigate and analyze the total phenolic content (TPC), antioxidant activities (FRAP, ABTS, and DPPH), and antibacterial properties of lotus (Nelumbo nucifera) extracts. Lotus leaves, stems, and seed pods were extracted with deionized water at $95^{\circ}C$, and with 70.5% ethanol at $85^{\circ}C$. The TPC ranged from 8.12 to 215.12 GAE mg/g. The ethanol extract of the seed pod had the highest TPC, and the TPC of the corresponding deionized water extract was 161.45 mg/g. FRAP values ranged from 104.03 to $3,546.39TEAC\;{\mu}mol/g$, ABTS radical cation scavenging activities ranged from 105.11 to $3,956.94TEAC\;{\mu}mol/g$, and DPPH radical scavenging activities ranged from 37.29 to $2,549.46TEAC\;{\mu}mol/g$. $EC_{50}$ values ranged from 0.26 to 9.63 mg/mL, and 0.31 to 21.21 mg/mL for ABTS and DPPH, respectively. The ethanol and deionized water extracts of the seed pod showed higher TPC and stronger antioxidant properties (FRAP, ABTS, and DPPH) than those of characteristic of the leaf extracts. The ethanol and deionized water extracts of the seed pod showed antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa with inhibition zones of 9.0 to 14.0 mm, and the ethanol extract of the leaf showed antimicrobial activity against B. subtilis and S. aureus with inhibition zones of 9.0 and 10.0 mm, respectively. Thus, the lotus seed pod could be used to produce novel teas, and could be a potential source of therapeutic ingredients for food and medicine.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.1044-1054
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• 2020

This study was performed to investigate the effects of lotus leaf hot water extracts treatment on the quality and stability of eggs using impregnation treatment through ultrasonication during storage. A total of 480 eggs were categorized into four treatment groups (n=30 each)-non-treated (CON), soaked for 30 min in lotus leaf hot water extracts without ultrasonication (T1), sonicated in distilled water (T2), and sonicated in lotus leaf hot water extracts (T3)-and stored for 15 d at 30℃. The egg weight, Haugh unit (HU), egg grade, albumen height, yolk color, eggshell thickness, eggshell breaking strength, and weight loss were measured for egg quality assessment. 2-Thiobarbituric acid reactive substance (TBARS) and volatile basic nitrogen (VBN) contents were measured as stability indicators. Additionally, total phenolic contents (TPC), total flavonoid contents (TFC), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were evaluated. The HU, egg grade, albumen height, and yolk color of T3 were significantly higher than those of CON (p<0.05). No significant differences in eggshell thickness and eggshell breaking strength are observed among the groups. The weight loss of T3 was significantly lower than that of the other groups during storage (p<0.05). The application of lotus leaf hot water extracts also significantly reduced TBARS and VBN (p<0.05). The TPC, TFC, and DPPH radical scavenging activity of T3 were significantly higher than those of the other groups (p<0.05). These results suggest that lotus leaf hot water extracts may be useful as a natural ingredient for improving the quality and stability of eggs during storage.