보고서 정보
주관연구기관 |
목포대학교 Mokpo University |
보고서유형 | 최종보고서 |
발행국가 | 대한민국 |
언어 |
한국어
|
발행년월 | 2010-06 |
과제시작연도 |
2009 |
주관부처 |
농림축산식품부 Ministry of Agriculture, Food and Rural Affairs(MAFRA) |
등록번호 |
TRKO201400026269 |
과제고유번호 |
1545001124 |
사업명 |
농림기술개발 |
DB 구축일자 |
2014-11-14
|
DOI |
https://doi.org/10.23000/TRKO201400026269 |
초록
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○ 연구 결과
- 연잎, 연근, 종자, 꽃에서 주요성분, 항산화도, 항균 효과 등 생리활성 효과 구명. 실험실과 동물에서 기능성 증진(항비만, 항스트레스, 뇌기능개선, 면역증진) 생리활성 물질인 neferine, liensinine, apigenin 8-C-glucopyranose 추출, 분리, 동정, 구조 확인
- 성인과 비만자에서 연 식이섬유 제형 섭취로 지질대사개선과 체형개선으로 항비만 효과 검증
- 연잎과 연근에서 식이섬유 분리, 추출, 정제, 대량생산기술 개발
- 김치, 장아찌, 간장, 음료, 식혜,
○ 연구 결과
- 연잎, 연근, 종자, 꽃에서 주요성분, 항산화도, 항균 효과 등 생리활성 효과 구명. 실험실과 동물에서 기능성 증진(항비만, 항스트레스, 뇌기능개선, 면역증진) 생리활성 물질인 neferine, liensinine, apigenin 8-C-glucopyranose 추출, 분리, 동정, 구조 확인
- 성인과 비만자에서 연 식이섬유 제형 섭취로 지질대사개선과 체형개선으로 항비만 효과 검증
- 연잎과 연근에서 식이섬유 분리, 추출, 정제, 대량생산기술 개발
- 김치, 장아찌, 간장, 음료, 식혜, 만두, 두부, 국수, 연잎 추출액, 식혜, 차, 연밥 개발 및 상품화
- 연잎과 연근 수확, 건조, 분말제조, 유통, 포장을 통한 연잎과 연근 분말 개발
- 연근 자외선, 알콜처리, PE필름 진공 포장, 저장온도 설정으로 저장기간 기존보다 20일 연장
- 연근 절편과 조각 제조공정 개발을 통한 제품 개발 및 중국산과 품질 우수성 구명
- 연 종자와 근경에서 개화 관여요인, 단근과 적엽처리를 통 개화조절과 개화시기 예측
- 공기와 수압 분사노줄을 이용한 연근과 흙을 분리할 수 있는 연근 굴취기 개발
Abstract
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〈Sub- project 1〉Nutrient components and their bio-activities in lotus organs and its epidemiological studies
1. In general and nutritional composition of different part of dried white lotus (Nelumbo nucifera), the water contents of dried powder of root, leaves, seeds and flowers were 1.76, 4.22,
〈Sub- project 1〉Nutrient components and their bio-activities in lotus organs and its epidemiological studies
1. In general and nutritional composition of different part of dried white lotus (Nelumbo nucifera), the water contents of dried powder of root, leaves, seeds and flowers were 1.76, 4.22, 2.75, and 7.62%, respectively. Crude protein content in the seeds was higher than those in different parts. Carbohydrate content in the root was higher than those in different parts, but the crude lipid content was comparatively lower. The potassium content of the minerals in the roots was much higher than those in other parts. Additionally, the iron content of flowers was much higher than those in different parts. The main sugar in the leaves was maltose, the main sugar in the roots was xylose and that in the seeds was glucose. Among organic acids, malic acid showed the highest level in the leaves, flowers and roots, while glutaric acid was the highest in the seeds. Total dietary fiber were 21.97% for roots, 54.90% for leaves, 27.76% for seeds and 44.0% for flowers.
2. The preventive and therapeutic potency against oxidative stress and diabetic complications of N. nucifera were evaluated via the 1,1-diphenyl-2-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC), and total reactive oxygen species (ROS) assays, as well as the rat lens aldose reductase (RLAR) and advanced glycation endproducts (AGE) assays. The leaf extract of N. nucifera exerted potent antioxidant effects as well as marked inhibitory effects for RLAR and AGE formation, corresponding to high values for total phenolic content (TPC) and total flavonoid content (TFC). Among several solvent fractions, the EtOAc and n-BuOH fractions, having prominent TPC and TFC values, showed significant antioxidant effects in the DPPH and TEAC assays. Moreover, the EtOAc fraction exhibited superior inhibitory effects in the total ROS, RLAR, and AGE assays, with IC50 values of 9.4, 2.4, and 28.2 mg/mL, respectively. Also, the HPLC profiles of the active EtOAc fraction indicated that quercetin 3-O-b-D-glucopyranoside (Qc-3-Glc) and Qc 3-O-b-D-glucuronopyranoside (Qc-3-Gln) were two of its major components, as well as Qc 3-O-b-D-galactopyranoside (Qc-3-Gal) as a minor compound.
3. Also, we investigated the effect of N. nucifera parts on the gastric ulceration, Ig G and liver damaging factors of rats in immobilization stress. For the induction of stress, rats were stressed by immobilization for 2 hours in a day during 2 weeks, and administrated daily at a dose of 400 mg/kg extracts of lotus parts. In gastric ulceration using by tissue staining method was not changed in lotus treated groups compare with control group. As a results of measuring Ig G levels of serum, lotus treated groups (leaf, root, stamen) were not shown significantly differences, but shown the increasing inclination. In special, liver damaging factors of GOT and GPT were decreased significantly in lotus treated group compare with control group.
4. To elucidate anti-hypodlycemic and obestic effects of fiber isolated from N. nucifera, db/db mice were allocated control group and N. nucifera fiber group. Mice were received daily oral injections of fiber at a dose of 100 or 400 mg/kg body weight for 8 weeks. Body weight and food efficacy show the decreasing pattern at the 7 and 8 weeks by feeding of N. nucifera fiber. Fiber treated groups significantly decreased blood glucose, glycosylated hemoglobin, triglyceride, and cholesterol levels in serum. Also, insulin level in serum significantly increased by the oral treatment of fiber in a dose dependent manner, but did not show a beneficial effect on the abodominal and subcutaneous fats in db/db mice.
5. A new b-cyclogeraniol diglycoside (5), along with four known components, cycloartenol (1), p-hydroxybenzoic acid (2), vanilloloside (3), and 5-O-methyladenosine (4), were first isolated from the n-BuOH fraction of Nelumbo nucifera stamens. The chemical structure of b-cyclogeraniol diglycoside was elucidated as 1-hydroxymethyl-2,6,6-trimethyl-1-cyclohexene-9-O-b -D-glucopyranosyl-(1 6)-b -D-glucopyranoside (nuciferoside) on the basis of chemical and spectroscopic evidence, including 1D, 2D NMR, and MS. The anti-Alzheimer effects of 1-5 were evaluated via the acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and b -site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) inhibition assays. Compounds 1-3 and 5 showed good and noncompetitive inhibition against AChE with IC50 values of 11.89, 20.07, 4.55, and 3.20mM and Ki values of 15.71, 25.44, 7.76, and 5.76mM, respectively. Compounds 1, 2, 3 and 5 also possessed BChE inhibitory activities with IC50 values of 13.93, 62.29, 205.78, and 83.06mM, respectively. The selectivity index (SI) values of 1, 2, 3, and 5, calculated from IC50 values of BChE and AChE, were 1.2, 3.1, 45.7, and 26.0. However, all isolated compounds lacked BACE1 inhibition up to 100mM.
6. Alzheimer disease(AD) is a progressive neuro-degenerative disorder causing dementia. One of the most consistent neurotransmitter altercations found in brain of AD patient is a loss of cholinergic markers, cholineacetyltransferase(ChAT) and acetylcholinesterase(AChE).
7. We examined the antiamnestic effect of NNS in scopolamine-induced amnestic rats with using passive avoidance test, estimating AChE activity and ChAT immunochemistry. Latency time of passive avoidance test in NNS treated group have significantly increased as 54% than those of scopolamine treated group. Inhibition on AChE activity in NNS treated group have significantly increased 7.35% than those of control group. The number of CHAT-positive neurons in NNS group has increased as 14% than those of control group.
〈Collaborative- project 1〉Effectiveness of anti-obesity in adult and obese adult eaten dietary lotus fiber
1. In order to evaluate the anti-obesity effect of lotus dietary fibers (5 g/day, 12 weeks, pill-type), we implemented clinical trial on healthy adult((M: 40, F: 23, BMI <25) and obese adult (M: 41, F: 20, BMI >23.5). The clinical trial on healthy adult showed that body fat(%) and serum lipid profile level of lotus dietary fiber trial group were lower than comparison group.
2. The clinical trial on obese adult showed that TG, BP, FBS of lotus dietary fiber trial group were lower than comparison group, but others not. And changes of adipokines (leptin, resistin etc) were not significant. These results revealed that anti-obesity effect on obese adult of lotus dietary fibers (5 g/day, 12 weeks, pill-type) was evident in a few indices and supplementary studies were needed for development of lotus dietary fiber products: composition of lotus fibers, changes of fibers composition after fiber extraction procedures etc.
〈Collaborative- project 2〉Development processing product of lotus and commercialization of these product
1. To develop the efficiency of lotus, we developed jook, tofu, pickle, noodles,dumpling shell that contained lotus root and lotus leaf powder. The quality characteristics and sensory evaluation of these products were analyzed.
The physical and sensory properties of Jook that added with lotus leaf powder(LLP) were investigated. Since the level of lotus leaf powder(LLP) in the samples was increased, both L-values and a-values were also decreased, and only b-values were increased. In addition, the Jook had high viscosities and low spreadable values as the amount of LLP increased. Sensory characteristics, such as: color intensity, viscosity, astringency, and nutty taste increased significantly with the addition of LLP. And the results of the consumer acceptability test showed that the Jook containing 2%~3% LLP had the highest score. To enhance the quality of Jook, a 2% addition of LLP would be the most beneficial. The quality of characteristics of tofu was investigated by preparing with different concentration of LLP. The yield rates of the tofu samples did not differ significantly according to the level of added LLP. However, there was a significantly decrease in the pH and a significantly increase in the acidity. The L- values and a-values of samples decreased as the amount of LLP in the formulation increased, whereas the b value increased. Furthermore, hardness significantly increased as the level of LLP increased. In terms of overall acceptability, the preferred tofu samples were the control and that containing 0.2% LLP. Quality characteristics of lotus root pickle added with beet extract were investigated. Lotus root slices were salted with NaCl, soaked into pickling solution, and then stored at 20℃. The pH of the experimental groups decreased slowly during the fermentation. In terms of color values, both L and a values were decreased, but b values were increased, with increasing beet extract content. Overall, based on sensory evaluation, lotus root pickle added 30% beet extract was preference over the other samples. The quality characteristics of noodles was investigated with adding LLP. The gelatinization points of the composite LLP-wheat flours were increased and had viscosity at 95℃, after 15 minutes and maximum viscosity of those were decreased, as the LLP content was increased as measured by amylograph. As more LLP was added, both L and b value were decreased, a value was increased in color values and weight and volume of cooked noodle and turbidity of soup were increased. For the textural characteristics, the LLP additive increased hardness and decreased adhesiveness, cohesiveness and springiness. Overall, the noodles made with 5% LLP were preferred more than the other noodles as tested by sensory evaluation. Dumpling shell samples were prepared with wheat flour along with the addition of different amount of LLP, followed by functional measurements and sensory evaluation. The addition of LLP content increased hardness and decreased chewer in all samples. Overall, sensory evaluations proved that dumpling shell with 3% added LLP was preferred over the other samples.
2. We developed various kinds of processing product using lotus, such as extract leaf fermented, powder, juice, Sik-Hae(rice nectar), Ssam-Bap(boiled rice). The extract contained 0.1g ash, 53.46g carbohydrate, 13.14g crude protein, 0.01g crude fat, 2.58g NaCl, 0.002g saturated fat and 0.00g/100g cholesterol. Sensory quality in the extract of fermented lotus leaf is much better in maturation leaves than those of young and its tasty improved in clay bowl compared to glass bowl as fermentation tools. The extract inhibited the expression of MMP-2 in HASMC and improved the wound healing. Antioxidant activity increased with increasing the extract concentration, while NO activity decreased. The extract from fermented leaf has no fat, trans fat and cholesterol, so its extract treated to chicken, pork, beef, and vegetables as functional food source. Sensory quality in juice is much improved with added the extract of both lotus leaves tea and roots. Lotus juice developed with addition of extract leaf fermented to the extract of lotus leaves tea and root.
Sensory quality was highest in mixture of 11.% fermented leaf extract to 72.5 leaf tea extract and 16.5% root juice among treatments. Sensory qualities of powder in both leaves and flower is much improved by developing proper processing procedure during making these teas. These powder is good source of vitamin and mineral as foods additive for health improvement. Sik-Hae product added extract of lotus leaves has good source of minerals, such as calcium, iron, sodium compared to rice nectar. Ssam-Bap product using lotus leaf has much bioactive compounds, such as vitamin A, beta-carotene, mineral compared to rice boiled. All these processing product will improved value added of lotus and it will make money for lotus farmer.
〈Sub- project 2〉Extension shelf life, development powder and minimally processed product and flowering regulation in lotus
1. The ventilation and heat treatment before storage is not effective on the weight loss and hardness during storage of Nelumbo nucifera rhizomes. The weight and hardness of N. nucifera rhizome stored at 10℃ was greatly lowered compared to 15℃ during storage period. But, in rhizomes stored at 0℃, the weight and hardness was highly maintained and occurrence rate of microorganism, as fungus and bacteria was lowered. Therefore, for storage quality improvement of N. nucifera rhizome, storage at 0℃ was more effective than storage at 10℃ or 15℃. The storage quality by packing material in N. nucifera rhizomes was examined. In packed with PE film of 0.1mm thickness, the weight and hardness of rhizome were highly maintained, and occurrence rate of microorganism was lower at 30 days after storage than in the other thin PE films. Also, occurrence rate of fungus and bacteria was lowered in washed rhizomes than in non-washed rhizomes. The vacuum packed with PE film in rhizomes showed the highest hardness among treatments. When rhizome harvested between October and March was stored, microorganism in rhizome harvested on October occurred at 70 days after storage, and microorganism in rhizome harvested between November and March occurred at 40 or 50 days after storage. Treatment of ultraviolet rays for 0, 15, 60, 240 minutes was not effective until 90 days after storage. Treatment of 0, 1, 2, 5, 10% alcohol solution was not effective in rhizome storage. But, when it was treated with 2% or 5% alcohol solution, changes in weight and hardness of rhizome were slightly influenced relatively. Also, soaking with chitosan solution and citric acid were not effective in rhizome storage.
Therefore, for long-term storage of N. nucifera rhizome, it was more effective to store at 0℃ after vacuum packing with PE film of 0.1mm thickness following rhizome washing.
2. Lotus leaves were harvested on June 15, July 15, Aug. 15, Sep. 15, while roots were harvested on Nov. 15, Dec. 15, Jan. 15, Feb. 15 respectively. After harvesting, leaves and roots were dried at 50℃ drying chamber. Contents of starch, ascorbic acid, total phenolics, amino acids and inorganic elements were influenced by harvest date in both lotus leaves and roots. The optimal date of harvest was Aug. 15 in leaves and Jan. 15 in roots. In order to know the best drying temperature, both leaves and roots of lotus were dried at 30, 40, 50, 60, 70℃, respectively. Marketability and quality of powder product in both leaves and roots was considerably changed by drying temperature. The optimal drying temperature was 50℃ in leaves and roots, respectively. The powder product sealed with glass bowl, plastic bottle, polyethylene and aluminium foil bag were stored at 0 and 20℃ for 12 months. Contents of chlorophyll, starch, fiber, ascorbic acid gradually decreased with time and those content highest in aluminium foil bag among treatments in all temperature. Quality of powder product during storage maintained best when these powder were stored at 0℃with sealed either glass bowl or aluminium foil. After making processing procedure, we developed powder product value added, such as lotus leaves powder and its root powder.
3. To develop fresh-cut product using lotus roots, firstly we screened the antioxidant agent such as 1% citric acid, 1% ascorbic acid, 0.2% N-acetylcystein, 0.5mM hexylresorcinol, 0.1% Ca propionate. Ascorbic acid 1% combined with citric acid 1% has good property to prevent browning in lotus during storage. In treatment methods of anti-browning agent, flesh browning much decreased with ascorbic acid 1% plus citric acid 1%(CA) following hot water dip at 50℃ for 3 min. Browning of fresh-cut roots significantly decreased with keeping solution of CA solution during storage. To determine the shelf life of fresh-cut roots, its roots were stored at 0, 5, 10, 20℃ for 14 days, respectively. Shelf life of lotus roots extended with increasing fresh quality by decreasing PPO activity and ethylene production when roots were stored at 0.℃. To screen the optimal lotus cultivar for fresh-cut product development, we evaluated the quality in native cultivars of 'Inchisa', 'Muan', 'Garam', 'Chungyang'. There was no difference firmness, Hunter 'L' and amino acids among cultivars, but total phenolics and antioxidant activity slightly higher in 'Muan' than that other cultivar. In order to prevent microorganism infection, we treated electrolyzed oxidizing water, ozone water, sodium hypochloride for fresh-cut roots and then stored at 0℃ for 9 days. we did not find any harmful microorganism in all tratments, but bacteria number lowest in sodium hypochloride among treatments.
Changes in microorganism numbers in fresh-cut roots according to storage temperature, its number increased with rising storage temperature, especially at 20℃. There was no detect any chemical residues in fresh-cut roots. Finally, we establish the making procedure of fresh-cut product and then developed two kind of product, such as slice and peeled bulk roots. We compared the quality of fresh-cut lotus between Korea's and China's product. The quality of fresh-cut lotus product is much better in Korea's product than that China', while the marketing price is much cheaper in China's product compared to Korea's. If we develop the fresh-cut product produced in Korea, its will be well sale in market place because of high freshness and quality characteristics.
4. To gather the basic data on bioactive compounds and its bio activity of leaf extracts, the leaves of four species of white lotus including 'Garam', 'Choeue', 'Baekwageollyeon', and 'Seungdal' were harvested. Total phenol contents were highest in the extracts of heated-water from the white lotus 'Choeue' by 78.3㎍/mL and in ethanol extracts from 'Baekwageollyeon' by 146.8㎍/mL. DPPH radical scavenging activity was highest at extracts of the heated-water and ethanol extracts of white lotus 'Seungdal' by 83.9% and 94.0%, respectively. Total flavonoid contents in the ethanol extracts of 'Seungdal'(63.6㎍/mL) and 'Choeue'(92.2㎍/mL) were higher than those in the heated-water extracts of 'Choeue' (28.8㎍/mL). Nitrite scavenging activity of heated-water extracts of 'Choeue' extracted was 69.2%, and ethanol extracts of 'Baekwageollyeon' 80.7%. No significance in tyrosinase inhibition activity of the leaf extracts from four species of white lotus among those species and solvents were observed. Anti-microbial activity of the ethanol extracts was higher than that of the heated water, showing bigger inhibition diameter (8.3 to 11.2mm).
We also investigated the total phenol, antioxidant activity, flavonoid, nitrite scavenging, tyrosinase and antimicrobial activity in the extracts of white lotus flowers including 'Garam', 'Choeue', 'Baekwageollyeon', and 'Seungdal'. Total phenol and flavonoid contents were highest in the extracts of heated-water from the white lotus flower 'Garam' among cultivars. Nitrite scavenging and tyrosinase activities were much higher in 'Seungdal'and 'Choeue' than that 'Choeue' and'Baekwageollyeon' regardless of extract methods.
5. To know the mechanism and physiology of flowering in lotus grown lake located in Muan county, firstly we investigated the of flowering effect by cultivation environment. Between cultivation condition and flowering, flowering was influence by the temperature, rainfall and sunshine duration. It was shown that more analyses of the inner factors such as the age of lotus roots, and the management factors such as the management of water depth, the digging and planting times and fertilization were needed. To estimate of days to flowering by the kinds of the white lotus, the percent flowering and the yield of lotus leaves. Blooming period of the white lotus c.v. 'Garam', 'Chungyang', and 'Inchuisa' were June to early in July and mid-July.
And that of c.v. 'Muan‘ and 'Baekhwageonryeon' were about the middle of July and late in August. From the emergence of flower bud to the flowering of the white lotus had taken 19-20 days. Flower stalk length of the white lotus were generally about 97-162cm. In mid-August, the number of the marketable lotus leaves per 3.3m2 were about 25.0-35.8, and their fresh weight were about 1.57-3.26kg. It was consumed that the yield of lotus leaves should be considered in the selection of the kinds of the white lotus. To examine characteristics of rhizome growth and flowering of white lotus grown lake in Muan county. Time to flowering from the emergence of flower stalk on the above-ground parts were required 16 days. White flowers from the lotus were 15.3cm in height and 28.2cm in width, their longevity was 3.3 days and the averaged flower fresh weight was 29.2g. The results conclude that optimum number of nodes on the main rhizomes for blooming the white lotus flowers should be over 8 nodes before the rhizome enlargement. To gather the basic data on the effective seedling propagation, cultivation, early flowering of the white lotus grown lake in Muan county. The maximum leaf length and width were 18cm and 19cm. And the maximum leaf stalk length was 56cm.
Rhizome was mainly enlarged in the sub-apical regions of the main rhizome early in August. Number of the enlarged rhizomes per one seedling were 3.7, and their fresh weight was 78.8g. It was assumed that these above results will be helpful to the early flowering of the native white lotus seedlings in Muan county, the marsh landscape architecture, and the production of seed bulbs. To examine the characteristics of flowering and fruiting in lotus grown lake in Muan county. Lotus plants of 21.4% were not bloomed, resulting from the insufficient securing of internodes in the main rhizome and the blind. Lotus seeds, 1.5±0.2cm in length and 1.4±0.4cm in width, were ripened at about 30 days after flowering, and their fresh weight per seed was 1.3±0.6g. We, therefore, concluded that lotus ‘Yellow Bud' as a ornamental plant should be grown up to 8 in the node number of main rhizome until mid-July. To examine into effect of plant growth regulator treatment on the lotus flowering, lotus leaves and root growth in lotus grown lake in Muan county. Lotus 'Yellow-bud' in control was flowered on Jul. 30, however, that treated ABA 1,000ppm and ethephon 1,000ppm on Jul. 27, which flowering was promoted about 3 days. Number of lotus leaves in control were 21, however, that treated ethephon 500ppm decreased by 16, and that treated GA 100ppm increased by 28. To examine the effect of the leaves harvesting amount on the number of flower flowered and the enlarged rhizome yield during the cultivation of the white lotus grown lake in Muan county. Enlarged rhizome yield per plant were that control (4,210g), 25% leaves harvesting treatment (3,162g), and 50% leaves harvesting treatment (2,588g). Number of enlarged rhizome per plant were that control (9), 25% leaves harvesting treatment (6), and 50% leaves harvesting treatment (5).
Consequently, it should be considered that the lotus leaves harvesting have led to the decrease the number of plants flowered and the enlarged rhizome yield. We have planted the containers with the lotus, 'Yellow-bud' on Apr. 15, 2008, and have sprayed chitosan, salcylic acid and methyl jasmonate on the lotus leaves on Jul. 1, 7 and 14. We have also measured the flowering period, the number of lotus leaves and the yield of lotus root. Lotus in control flowered on Jul. 30, however, that treated chitosan 500ppm flowered on Jul. 27, which promoted the lotus blooming by 3 days. Overall number of lotus leaves were 21-22, except salcylic acid 3,000ppm by 14, methyl jasmonate 1,000ppm by 16 and methyl jasmonate 250ppm by 18. The yield of lotus root in control was 564g, however, that treated salcylic acid 3,000ppm and methyl jasmonate 1,000ppm decreased by 385g and 362g. respectively. And that treated chitosan 500ppm increased by 584g.
〈Consignment- project 1〉Development of the lotus root harvester using the fluids of high pressure
1. Lotus roots are usually cultivated in the clay soil of paddy field in Korea.
Cultivation area of lotus roots as an alternative of a rice plant has been increased greatly during several years due to the decrease of rice price. Lotus roots are grown horizontally in the depth of about 30 cm inside the clay soil. Consumption of lotus roots are increased as the health food. The harvesting of lotus roots requires the great labor and is usually doing by manual labor as digging with hoe.
2. The objective of this study was to develope the lotus root harvester with easy by soil breaking with the injection of high pressure fluid into the soil. The constructed lotus root harvester which uses high pressure air is composed of the main body including nozzle, high pressure container, handle, and lever and an air compressor.
The degree of soil breaking by this harvester was analyzed with using three different nozzles. Also, the lotus root harvester which uses high pressure water was constructed.
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