FIELD OF DISCLOSURE
The present invention relates to an apparatus for extracting toxic principles from cassava plant bio-wastes. The present invention also relates to a process for carrying out such extraction of the toxic principles from cassava bio-wastes.
BACKGROUND
Manihot esculenta (Crantz), commonly known as cassava (tapioca) is an all season food crop largely cultivated in the tropical and subtropical countries for its edible starchy tuberous root. It is an important and cheap source for energy rich food. It is the fourth most important carbohydrate source in the world, next only to com, wheat and potato. According to Food and Agricultural Organization (FAQ) of the United Nations, over 600 million people in Africa, Asia and Latin America depend on cassava plant for their food and incomes. Cassava tubers are also used for the production of cattle feed and starch based products.
The cultivation of cassava produces high quantities of bio-wastes in the form of leaves (approx. 6 tonnes per hectare) and tuber rinds (approx. 5 tonnes per hectare) after cassava crop is harvested.
Normanha (1962) harvested an equivalent of 9 tonnes of dry matter per hectare. Ahmed (1973) reported that the dry matter productivity of cassava leaves was 7.5 tonnes per hectare. The disposal of this huge amount of bio-waste is very cumbersome. The problem associated with the disposal of cassava bio-waste is that when the cassava plant is ground, the enzyme such as linamarase (found in the cell wall) gets exposed to the compounds like linamarin and lotaustralin which in turn release hydrogen cyanide. The hydrogen cyanide is toxic. Furthermore, due to
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the presence of certain toxic principles, e.g. cyanogens (cyanoglucosides) in cassava bio-wastes it cannot be used for mixing in or as cattle feed.
In India, cassava is widely cultivated in about 13 states, but Kerala and Tamil Nadu contribute the major share in its cultivation. The cultivation is spread over an area of 0.24 x 10^ hectare in the southern peninsular region with a production of 6.7x 10^ tonnes with the highest average productivity of 27.92 tonnes per hectare in the world.
Tubers are also extensively used for industrial purposes to produce starch, sago, fructose, glucose etc. The industrial production of starch in India is estimated to be 0.18 million tonnes from 1137 factories. However, during each cassava crop harvest, a huge quantity of leaves and tuber rinds are rendered useless as bio-wastes.
EXISTING KNOWLEDGE
Conventional method adopted for the detoxification of cassava leaves is by sun drying, but this method is time consuming and mainly depends on the availability and intensity of the sun-light. Other than the method of sun-drying, some other methods have also been adopted for the detoxification of cyanogens from cassava leaf Emmanuel et al. (1982) reported that blanching (10 minutes), mashing and boiling for 20-80 minutes enhanced the detoxification of the leaves. Blanching alone results in the loss of 57 % of the free (non-glycosidic) cyanide content and of 60 % of the bound (glycosidic) cyanide. Although cassava leaves etc. can be used as cattle feed, no attempt has been made for extracting its toxic, however useful insecticidal principles from cassava bio-wastes. Till date, no technology is available for the mass-scale extraction of bio-pesticides from above mentioned cassava bio-wastes.
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The experiments conducted by the present inventors have proven that the bio-pesticides extracted from cassava leaves are very effective for controlling borer pests, e.g. red palm weevil (Rhynchophorus ferrugineus Oliver) in coconut and pseudo stem weevil {Odoiporous longicollis Oliver) in banana.
Rhynchophorus ferrugineus F. is the most noxious pest of coconut palm. Young palms below 20 years succumb to severe damage when infested by this pest. Palms infested by bud rot, leaf rot and injuries made by rhinoceros beetle are the pre disposing factors for red palm weevil infestation. Being an internal feeder, it is very difficult to detect the damage caused by red palm weevil at an early stage. Wilting of the central spindle, presence of chewed up fibers and presence of holes and cocoons in the trunk, oozing out of brown fluid from the trunk are the important external symptoms of red palm weevil attack. The symptom of their infestation becomes clear in advanced stages, the time at which the crown of the affected palm topples. The weevil muhiplies enormously in young coconut plantations costing loss to an extent of five to ten per cent. In young coconut plantations, crown, trunk and bole are the natural sites of damage. In older plantations, only crowns are infested. Many a time the insect completes several generations inside the crown or trunk feeding on the inner tissues until the trunk or crown becomes hollow and the tree gets killed. After the death of the palm adult weevils come out and seek fresh trees to attack.
The management of this pest is mainly relied upon very toxic systemic insecticides. Curative treatment with 0.1% of endosulfan (this insecticide banned in many countries has now been banned in Kerala) or carbaryl 1% {Abraham et.ai, 1989) is reported to be effective for management of red palm weevil. Stem injection of monocrotophos (its use has been restricted in Kerala) @ 10 ml per palm or monocrotophos and dichlorovos (5+5 ml) into a predrilled 10 cm deep hole in the stem {Muthuraman et.al, 1984). Root feeding method was used in
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some instances where monocrotophos or any other systemic insecticide is diluted with water and fed to the infested palm through the active root. However, in this case the pupal stages would escape from the effect and also there are chances of pesticide residues in the tender coconut water and kernel. Pseudo-stem weevil {Odoiporous longicollis Oliver)
The banana pseudo stem weevil or banana pseudo stem borer, a black 23-39 mm weevil, is a noxious pest on banana and plantains. It is monophagous and predominantly nocturnal in habit. All the stages of the weevil are present throughout the year in the infested plant (Padmanaban and Sathiamoorthy, 2001). Adults are good fliers will move from plant to plant. Its longevity lasts for one year and the sex ratio is 1:1.2 male to female. The mean number of eggs laid by a female after a single mating is 9 eggs at the rate of one egg per day. Eggs is yellowish elliptical, and is deposited by inserting the ovipositor through ovipositional slits cut by the rostrum on outer epidermal layer of sheath of the pseudo stem down to the air chambers. Oviposition takes place only in the leaf sheaths. The tunnel is widespread and may go as high as the fruit peduncle or to the lower most collar region near the rhizome. The larva has 5 instars and the development rate is highly depend on climatic factors with longer duration in winter than in summer. Infestation by the weevil normally starts in 5 month old plants. Early symptoms of the infestation are the presence of small pinhead sized holes on the stem, fibrous extrusions from the base of leaf petioles, adult weevils and exudation of gummy substances from the holes on the pseudo stem etc. During the advance stages of infestation, the stem, when split open, exhibits extensive tunneling both in the leaf sheath and in the true stem. Depth of the tunnel made by the larva may range between 8- 10 cm. Rotting occurs due to the secondary infection of the pathogens and a foul odour is emitted. When the true stem and peduncles are tunneled after flowering the fruit do not develop properly and causes premature ripening. Weakening the stem by larval tunneling may resuh in breakage by wind or inability to bear the weight of the maturing bunch. In the
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severely infested plantations, more than 20% plants do not flower, and crop loss is estimated to a range of 10- 90%. Severity of the loss is greater when infestation occurs at early vegetative stage (five months old). Owing to the deposition of high residues, organo chloride insecticides are restricted from its use against this pest, however stem injection of organo phosphorus compounds; particularly the very toxic monocrotophos is widely practiced. Fumigation of banana plants using aluminium phisphide is also in practice. The bio-pesticides extracted from cassava leaves are also useful in controlling pseudo-stem weevil (Odoiporous longicollis Oliver) in banana.
In addition to the above, a formulation of cassava leaf with neem oil and surfactant can control mealy bugs (Rhizoeus sp.) and scale insect {Aspidiella longicollis Cockerell) in stored tubers of yams and aroids also.
After the extraction of bio-pesticides such as linamarin and lotaustralin from cassava leaves and tuber rinds etc. by using this process, the residual bio-wastes become free from cyanogens, thus they can be directly mixed into or fed as cattle feed. The chemical analysis of the residual bio-pesticide extracted cassava leaves etc. obtained from this process shows that this residue has many nutrients capable of enriching cattle feed. Apart from carotenes, vitamin B1, B2 and C and minerals, these residues of cassava bio-wastes also have protein (39.35%), crude fat (6.79%), nitrogen-free extract NFE (30.8%) and crude fiber CF (18.01%). The extraction process devised by the present inventors is also found to be comparatively much quicker as compared to the traditional practice of sun-drying.
Agriculturists are badly in need for an eco-friendly pesticide and a process for detoxifying cassava plant material. Therefore, there is felt a need to provide an apparatus, in which cassava bio-wastes having toxic principles are subjected to mass-scale extraction in order to obtain bio-pesticides for making a viable
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commercial exploitation of these bio-wastes. Some of the objects of the present invention are as follows:
OBJECTS
It is an object of the present invention is to provide an apparatus for isolation of the toxic principles present in cassava plant bio-wastes.
It is another object of the present invention to provide an apparatus for extracting on mass-scale, the bio-pesticidal contents present in cassava plant bio-wastes.
It is a further object of the present invention to provide a process for removing toxic principles present in cassava plant bio-wastes.
It is a still further object of the present invention to provide a process for extracting on mass-scale bio-pesticidal contents from cassava plant bio-wastes.
It is yet another object of the present invention to provide a process for obtaining cassava bio-wastes, which are free of toxic principles and full of nutrients to be mixed in or fed as cattle feed in order to make useful the cassava bio-waste left¬over after cassava harvest.
Further objects of the present invention will be more apparent from the ensuing detailed description of the present invention.
SUMMARY OF THE INVENTION
In accordance with the present invention, an apparatus (100) for extracting bio-pesticides from cassava bio-wastes comprising:
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i) a motorized high speed mixer-cum-grinder (10) of predefined volume adapted to receive, mix and grind cassava bio-wastes and hot water into slurry,
ii) a jacketed processing vessel (12) of predefined volume comprising:
a) means for receiving the slurry from the mixer-cum grinder (10);
b) heating means (14) adapted to heat the slurry under controlled conditions for generating vapours of bio-pesticidal extracts present in the slurry;
c) condensing means (16) for condensing said vapours to obtain a condensate of bio-pesticide; and
d) a valve (30) for discharging the slurry.
iii) a sediment and water separator-cum-storage chamber (18) of predefined volume comprising:
a) filter means (20) adapted to receive and separate the residual bio-wastes and hot water; and
b) a drain (32) for draining hot water for recycling back to the mixer-cum-grinder (10);
iv) a bio-pesticide collecting tank (34) connected to the condensing means (16).
Typically, the motorized high speed mixer-cum-grinder (10) is disposed operatively vertically and comprises:
- a top loading arrangement,
- a V- belt and a pulley arrangement connected to a shaft having a seal,
- an impeller,
- a lid having a seal and clamping arrangement,
- a laterally disposed inlet fitted with a valve to control the flow of hot water,
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- a drain (22) provided at the bottom for discharging the slurry; and
- an outer casing.
Typically, the jacketed processing vessel (12) is vertically mounted on the floor and comprises:
- a flange on the top of the vessel with an arrangement for accommodating an 'O' ring,
- a lid fitted on the flange, said lid provided with a vapour outlet (24) acting as an inlet to the condensing means (16),
- an agitator (26) provided with a seal,
- an impeller (28) of a removable configuration,
- heating means (14) disposed around the jacketed processing vessel (12) for heating the slurry,
- a valve (30) provided at the bottom center of the vessel for discharging the slurry,
- a ceramic fiber insulation,
- a PID type temperature controller provided with thermocouple fitted on the top of the vessel,
an AC supply, and
- a condensing means (16) fitted with an angle such that the vapours
generated from the vessel flow through the condenser coil and is adapted to
be cooled by circulating water.
Typically, the sediment water separator-cum-storage chamber (18) is disposed horizontally and comprises:
- a plurality of wheels (36),
- a handle for moving sediment water separator-cum-storage chamber (18),
- a filter mean (20) having an inlet and a mesh fixed internally, and
- a drain laterally fitted with a valve (32).
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In accordance with the present invention, a process is provided for extracting bio-pesticides from cassava bio-wastes comprising the following steps:
- loading cassava leaves and tuber rinds along with tender twigs into the mixer-cum-grinder unit (10),
- mixing and grinding the loaded material with fresh or recycled hot water to form a slurry,
- transferring the slurry into a jacketed processing vessel( 12) for distillation,
- heating the slurry initially to about 60 °C to about 80 "C and then at 100V,
- agitating the slurry during heating to generate vapours of bio-pesticides present in the slurry,
- condensing the generated vapours of bio-pesticides by condensing means (16) to obtain condensate of bio-pesticides present in the vapours,
- collecting the bio-pesticides condensate in the bio-pesticide collection tank (34), and
- disposing the slurry.
In accordance with the present invention, the method step of disposing the slurry comprises the following steps:
- separating the residual bio-wastes and hot water from the slurry obtained from jacketed processing vessel (12) by passing the slurry through the sediment water separator-cum-storage chamber (18) disposed at the bottom of the jacketed processing vessel (12),
- removing solid wastes for drying and storing for use in subsequent cattle feed enrichment, and
- recirculating separated hot water by pumping it back to a mixer-cum-grinder unit (10).
In accordance with the present disclosure there is also provided a bio-pesticide comprising hydrogen cyanide and water.
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BRIEF DESCRIPTION OF ACCOMPANYING DRAWING
The disclosure will now be described with reference to accompanying drawing. Figure 1 illustrates a schematic diagram of the apparatus to extract bio-pesticides from cassava bio-wastes
Other objects and advantages of the present invention will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present invention.
DETAILED DESCRIPTION OF ACCOMPANYING DRAWINGS
This apparatus (100) includes three main sub-units, which will be described in detail:
i) Motorized high speed mixer-cum-grinder (10), ii) Jacketed processing vessel for distillation (12), and iii) Sediment water separator-cum-storage chamber (18).
i) Motorized high speed mixer-cum-grinder (10) has a capacity of 25 liters and is disposed operatively vertically with an arrangement for loading from the top. It is indirectly driven by using a V- belt and a pulley arrangement by means of a drive shaft which is made of stainless steel (SS) and having a mechanical sealing to make the mixer-cum-grinder chamber leak-proof An impeller made of SS is provided inside which is of removable configuration. The sub-unit is covered by a lid having a neoprene seal and clamping arrangement. An inlet for hot water is provided laterally in this sub-unit for passing hot water from the sediment/water separator and storage chamber (18). This inlet is fitted with an SS valve to control
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the flow of hot water inside the sub-unit. A drain (22) is provided at the bottom for discharging the slurry. An outer casing made of powder sheets is also provided on an angled frame.
ii) Jacketed processing vessel for distillation (12) is also of a vertical configuration and is mounted on floor having heating, agitation and distillation devices. The capacity of this sub-unit is 75 liters.
The agitator (26) is powered by a variable speed motor with a gear-box assembly. The agitator shaft is made of SS and provided with a mechanical seal to prevent the high pressure vapours from leaking through the gap between the body and shaft and to make the chamber leak-proof
The impeller (28) is also made of SS and a removable configuration. The slurry obtained in mixer-cum-grinder (10) is passed via a pipeline to the jacketed processing vessel (12) for distillation. The slurry enters through an inlet provided at the side below the flange.
The vessel top portion is provided with an SS flange having an arrangement for accommodating silicon 'O' ring to make the lid and flange match therewith. This sealing arrangement prevents any leakage of vapours from the jacketed processing vessel (12).
A drain having a ball-valve (30) is provided at the bottom center of the jacketed processing vessel in order to discharge the slurry to the filter separator disposed downstream thereof This vessel has ceramic fiber insulation.
A heating mean (14) is disposed around the jacketed processing vessel (12) for heafing the slurry mixed water up to about lOO^^C.
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The jacketed processing vessel (12) is also equipped with a temperature control, e.g. in the form of a digital auto-tuning PID type controller, to control the vessel temperature. This PID type controller is provided with thermocouple fitted on the top of the vessel to indicate and control the temperature of the slurry being processed inside this vessel by regulating the power supply to the heating elements through a solid-state power controller.
An AC supply is connected to power the various sub-assemblies thereof.
A vapour outlet is provided on top of the lid having an extension tube, which acts
as an inlet to the condenser.
The condensing mean (16) is made of SS tubes, tube sheets, outer cover, flanges etc. It is fitted with a structure at an angle such that the vapours generated from the vessel are made to flow through the condenser coil and then cooled by circulating chilled or tap water. The condensed vapours are collected in a bio-pesticide collecting tank (34).
iii) Sediment water separator-cum-storage chamber (18) has a horizontal configuration having wheels (36) and handle for moving it on the floor. It has a rectangular discharge chamber having a partial opening to accommodate a conical perforated filter basket (20) made of SS sheet. The filter basket (20) has an inlet for receiving the discharge from the process vehicle for separating sediments and water by means of a fine wire mesh internally fixed in order to pass this water into the tank. This chamber also has a drain fitted with a ball-valve (32) at the side of the tank for draining out the collected filtered water for recycling. This filtered water is pumped back into the mixer (10). Wheels are provided for moving sediment water separator-cum-storage chamber (18) just below the jacketed
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processing tank and moving it out when separated sediments and filtered water are to be removed.
The cassava leaves and tuber rinds along with tender twigs are collected from the field and directly loaded into the mixer-cum-grinder chamber of the extraction pilot-plant through an opening provided at the top of the vessel. The raw materials as obtained from cassava plant components are mixed with pre¬determined/sufficient quantity of water. The pre-determined quantity of hot water is supplied into vessel through an inlet provided at the upper side wall of the vessel. The cassava raw material mixed with pre-determined quantity of hot water is ground with the help of a rotating impeller provided in the mixer-cum-grinder vessel to obtain homogenized slurry of the cassava bio-wastes.
The slurry is then transferred to a jacketed processing vessel (12) via an outlet provided at the lower side wall of vessel near its bottom. The outlet of vessel is connected to an inlet provided in the processing vessel at the side below the flanges for loading the slurry via a connecting pipe.
In jacketed processing vessel (12), the slurry is mixed with the pre-determined quantity of water and heated to a pre-determined temperature required to obtain vapours of the bio-pesticide substances present in the cassava bio-wastes.
The temperature of the processing vessel is first maintained in the range varying between 60°C and 100°C. Then, the temperature of the jacketed processing vessel (12) is raised to 100°C. To facilitate the distillation of the bio-pesticide substances present in the cassava bio-wastes the heating of the slurry is carried out under continuous agitation by a "variable speed geared motor" fitted with the mechanical seal. Thereby, the vapour along with bio-pesticide components liberated on heating the slurry reaches the condensing means (16) via an out-let provided at the
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top side wall of the processing vessel (12), which is connected to condensing means (16).
The condensing mean (16) is continuously cooled by passing chilled or tap water through the condenser chamber. The distillate formed therein is collected into a bio-pesticides collection tank via an outlet provided in the condenser unit.
The two main bio-pesticidal cyanogenic glucosides which are extracted and collected in collection tank from the cassava are linamarin and lotaustralin. Linamarin is a glucoside of acetone cyanohydrin whereas lotaustralin is a glucoside of methyl ethyl ketone cyanohydrin.
When the distilled production comes down to its minimum level, the waste from the processing vessel is drained out through a second outlet provided at the bottom of the jacketed processing vessel into a filter separator-cum-storage chamber(18) kept at the bottom of the processing vessel. The solid waste is removed and hot water is reused by pumping it back into the mixer-cum-grinder (10), where fresh leaves, tuber rinds and twigs of cassava are loaded for mixing and grinding. The waste material obtained after extracting the bio-pesticidal contents is dried and stored for cattle feed enrichment.
The bio-pesticide extracted by the above process comprises the components such as linamarin, lotaustralin, hydrogen cyanide and water.
The present invention is further described in light of the following examples which are set forth for the purpose of illustration only and not to be construed for limiting the scope of the present invention.
Example-1
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I. 1 Evaluation of the bio-pesticide extracted from cassava against the larvae, pupa and adult of red palm weevil {Rhynchophorus ferrugineus F) in coconut under laboratory conditions.
Efficacy of the bio-pesticides prepared from cassava leaves and seeds were tested against larvae, pupae and adults of red palm weevil {Rhynchophorus ferrugineus F) in the laboratory conditions (26 ± 3°C, Relative Humidity 80 ± 5%) in comparison with commercially available insecticides.
The experiments were conducted in 250 ml plastic jars. Since the bio-pesticide from cassava leaf is highly volatile in nature, the experiments were conducted in two conditions; (i) jar tightly closed with its own lid (ii) jar closed with muslin cloth.
The following treatments were given:
Ti - Cassava leaf distillate (CLD) - 100% in an aerated container (jar closed with
muslin cloth).
Tz - Cassava leaf distillate (CLD) - 90% and Cassava seed extract (CSE) - 10% in
an aerated container (jar closed with muslin cloth).
T3 - Cassava leaf distillate (CLD) - 100%) in an air tight container (jar tightly
closed with its own lid).
T4 - Cassava leaf distillate (CLD) - 90% + Cassava seed extract (CSE) - 10% in an
air tight container (jar tightly closed with its own lid).
T5 - crude cashew apple extract - 10%.
T6-Neemazal- 10%).
T7-Carbaryl- 1%.
Ts - Carbaryl - 2 %.
T9 - Untreated control.
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The experiment was replicated thrice and each replication had 10 numbers, and 30 ml of the test solutions were used per replication. The total number of 270 larvae, 270 pupae and 270 adults were used for this laboratory test. In the treatments Ti to T6, 15 ml of the test solution was directly poured onto the larvae and remaining 15 ml was impregnated on cotton balls which were kept in the jar for slow release of the bio-pesticide. Tender coconut husk pieces were provided as feed. In the treatments T5 to Tg, the test solution was sprayed on larvae, as test a solution of T5 to T8 does not show any fumigation. Except feeding no treatment was given in the controlled batch. Pupae and adults were also subjected to the same treatment as that for larvae in separate experiments. Observations on mortality rate of larvae, pupae and adults were recorded at an interval of 24 hours after treatment (HAT) for two weeks. The results are provided herein Table 1.
Table. 1: Mortality of red palm weevils due to the treatments of biopesticides and synthetic insecticides
Treatments Mean mortality
(2 Weeks after treatment)
Larval Pupal Adult
Ti - Cassava leaf distillate (CLD) - 4.33 5.00 4.67
100% in an aerated container (jar closed (43.3) (50.00) (46.67)
with muslin cloth).
T2 - Cassava leaf distillate (CLD) - 5.33 5.33 6.33
90% and Cassava seed extract (CSE) - (53.3) (53.33) (63.33)
10%) in an aerated container (jar closed
with muslin cloth).
T3 - Cassava leaf distillate (CLD) - 10.00 10.00 10.00
100% in an air tight container (jar (100) (100) (100)
tightly closed with its own lid).
T4 - Cassava leaf distillate (CLD) - 10.00 10.00 10.00
90% + Cassava seed extract (CSE) - (100) (100) (100)
10% in an air tight container (jar tightly
closed with its own lid).
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Ts - Crude cashew apple extract - 100% I 4.00 I 2.33 | 2.33
(40.00) (23.33) I (23.33)
T6-Neemazal-10% 3.67 2.33 5.00
(36.67) (23.33) (50.00)
T7-Carbaryl-1% 6.33 7.00 7.33
(63.33) (70.00) (73.33)
Tg - Carbaryl - 2% 10.00 9.00 10.00
(100) (90.00) (100)
T9 - Untreated control 0.00 0.00 0.00
M M M
CD (P = 0.05) 0.873 1.14 1.19
C.V (%) 8^54 n?76 1122
Conclusion:
From the data it could be implied that the most promising result was obtained in the treatments T3 and T4 wherein larvae, pupae and adults recorded 100% mortality within 72 hours after treatment. However in all other treatments expect T7 & Tg, mortality was significantly low till one week after treatments. 100% mortality rate was also obtained for larvae and adults in Tg, but 10% pupae escaped and emerged as adults. T] and T2 manifested relatively low mortality of larvae, pupae and adults; the survived grubs turned into adult but died in 6-8 days after emergence. Mortality due to the treatments T5 and Tg were relatively low than other treatments.
The recommended chemical, carbaryl (sevin) at 2% was on par with cassava leaf distillate.
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I. 2. Evaluation of the bio-pesticide extracted from cassava against the larvae, pupa and adult of red palm weevil {Rhynchophorus ferrugineus F) in coconut under field conditions.
Infested coconut palms from the farmer's field were recorded. Twelve palms below the age of 10 years were selected for each treatment, and another set of 12 infested but untreated palms were identified as control. Although the identified palms were in different stages of infestation, care was taken to ensure same stages of infestations in all the treatments. The treatments that gave promising results in the laboratory experiments (I.l) were only selected for treatments on field trial. The treatments were
Tr Cassava leaf disfillate (CLD) -100% in an air tight container (jar tightly closed
with its own lid).
T2- Cassava leaf distillate (CLD) - 90% + Cassava seed extract (CSE) - 10% in an
air tight container (jar tightly closed with its own lid).
Tj-Carbaryl- 1%
T4-Untreated control
The total numbers of 48 infested palms were selected. 36 palms were treated with the selected test solutions. Each treatment was replicated thrice and each replication had 4 palms. Untreated 12 infested palms were kept as control. Treatments were given through feeding/exit holes made by the weevil at the crown of the plant. In certain cases a new hole was made in the upper portion of the affected area in a little downward slanting position. 20 ml of bio-pesticide was injected using plastic syringe through the hole and released the solution. The hole was air tight with cotton and mud slurry to confine the fumes inside the trunk. Observations were continued for three months. The results are provided herein Table 2.
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Table.2: Comparative study of survival of palm trees due to the treatments of bio-pesticides of the present disclosure and commercially available synthetic insecticides.
Treatments Total 3 Weeks after treatment
number Total I Total
<*f number of number of
infested plants plants
plants survived the succumbed
infestation. to
infestation.
Ti - Cassava leaf distillate (CLD) - 12 10 2
100% in an air tight container (jar
tightly closed with its own lid).
T2 - Cassava leaf distillate (CLD) - 12 U 1
90% + Cassava seed extract (CSE) -10%) in an air tight container (jar tightly closed with its own lid).
Tj-Carbaryl- !%> 12 7 5
T4 - Untreated control 12 0 12
Conclusion:
The treatment T2 showed the most promising result with only one casualty out of twelve treated palms. This was followed by Ti wherein ten palms survived with two casualties. In T3, seven palms survived and five palms succumbed to death. In all the control palms infestation increased leading to gradual death of the palms. The Cassava leaf distillate (CLD) and Cassava seed extract (CSE) combination gives better resuh because CSE prevents the quick volatility of CLD and hence the toxicity lasts longer.
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Further, the chemical analysis revealed that no residue is retained 4 hours of its treatment, hence this can safely be recommended against borer pests in coconut, cashew, banana and other tree crops.
Bio-pesticide of the present disclosure can be effectively applied on the infested area by using polypropylene wash bottle with long curved tip. The long curved tip of the propylene wash bottle helps to effectively delivery bio-pesticide deep into the hole because of flexible tip of the bottle.
II. Evaluation of the bio-pesticide extracted from cassava against Odoiporus longicollis (Banana Stem weevil) or Banana Pseudostem borer.
Pseudo stem weevil of banana {Odoiporus longicollis Olive) was treated with different concentrations of bio-pesticide prepared from cassava leaf. Distilled water is taken as control and the mortality was recorded at every 15 min interval. Treatment with a concentration of 5% cassava leaf distillate caused 100% mortality on 60 minutes after treatment (Table-3).
TabIe-3: Mortality of pseudo stem weevil of banana due the treatment of bio-pesticide of the present disclosure.
% mortality
% concentration (Minutes after treatment)
of cassava leaf ^5 T^o [45 [60 Vl5
distillate in test
solution
Control 0 0 0 0 0
"(h5 0 0 0 0 100
1 0 0 50 100 100
1 0 Too 100 Too Too lo 0 100 100 100 Too
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TECHNICAL ADVANTAGES:
The Technical advantages of the present invention related to a mechanical device designed and fabricated for the extraction of bio-pesticide contents from cassava plant components and a process for the extraction of bio-pesticide contents from cassava plant components using the mechanical device of the present invention lies in providing:
1. Mass scale extraction of bio-pesticide contents from cassava bio-waste;
2. Easily fabricated mechanical device for small scale industries;
3. Cost efficient process in terms of utilizing the bio-waste remained after cassava harvesting; and
4. Easily adaptable process for small scale industries.
Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results.
"Whenever a range of values is specified, a value up to 10 % below and above the lowest and highest numerical value respectively, of the specified range, is included in the scope of the invention".
While considerable emphasis has been placed herein on the preferred embodiments, it will be appreciated that many embodiments can be made and that
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many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other changes in the preferred embodiments as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the forgoing descriptive matter to be implemented merely as illustrative of the invention and not as limitation.
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We Claim;
1. An apparatus (100) for extracting bio-pesticides from cassava bio-wastes
comprising:
i) a motorized high speed mixer-cum-grinder (10) of predefined volume adapted to receive, mix and grind cassava bio-wastes and hot water into slurry, ii) a jacketed processing vessel (12) of predefined volume comprising:
a) means for receiving the slurry from the mixer-cum grinder (10);
b) heating means (14) adapted to heat the slurry under controlled conditions for generating vapours of bio-pesticidal extracts present in the slurry;
c) condensing means (16) for condensing said vapours to obtain a condensate of bio-pesticide; and
d) a valve (30) for discharging the slurry.
iii) a sediment and water separator-cum-storage chamber (18) of predefine volume comprising:
a) filter means (20) adapted to receive and separate the residual bio-wastes and hot water; and
b) a drain (32) for draining hot water for recycling back to the mixer-cum-grinder (10).
iv) a bio-pesticide collecting tank (34) connected to the condensing means (16).
2. Apparatus (100) as claimed in claim 1, wherein said motorized high speed
mixer-cum-grinder (10) is disposed operatively vertically and comprises:
- a top loading arrangement,
- a V- belt and a pulley arrangement connected to a shaft having a seal,
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- an impeller,
- a lid having a seal and clamping arrangement,
- a laterally disposed inlet fitted with a valve to control the flow of hot water,
- a drain (22) provided at the bottom for discharging slurry and
- an outer casing.
3. Apparatus (100) as claimed in claim 1, wherein said jacketed processing
vessel (12) is vertically mounted on the floor and comprises:
- a flange on the top of the vessel with an arrangement for accommodating an 'O' ring,
- a lid fitted on the flange, said lid provided with a vapour outlet (24) acting as an inlet to the condensing means (16),
- an agitator (26) provided with a seal,
- an impeller (28) of a removable configuration,
- heating means (14) disposed around the jacketed processing vessel(12) for heating the slurry,
- a valve (30) provided at the bottom center of the vessel for discharging the slurry,
- a ceramic fiber insulation,
- a PID type temperature controller provided with thermocouple fitted on the top of the jacketed processing vessel(12), and
- a condensing means (16) fitted at an angle such that the vapours generated from the vessel flow through the condenser coil and is adapted to be cooled by circulating water.
4. Apparatus (100) as claimed in claim 1, wherein said sediment water
separator-cum-storage chamber (18) is disposed horizontally and
comprises:
- a plurality of wheels (36),
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- a handle for moving sediment water separator-cum-storage chamber (18),
- a rectangular discharge chamber having a partial opening,
- a filter mean (20) having an inlet and a mesh fixed internally, and
- a drain laterally fitted with a valve (32).
5. A process for extracting bio-pesticides from cassava bio-wastes comprising
the following steps:
- loading cassava leaves and tuber rinds along with tender twigs into the mixer-cum-grinder unit (10),
- mixing and grinding the loaded material with fresh or recycled hot water to form a slurry,
- transferring the slurry into a jacketed processing vessel(12) for distillation,
- heating the slurry initially to about 60 °C to about 80 V and then at 100°C,
- agitating the slurry during heating to generate vapours of bio-pesticides present in the slurry,
- condensing the generated vapours of bio-pesticides by condensing means (16) to obtain condensate of bio-pesticides present in the vapours,
- collecting the bio-pesticides condensate in the bio-pesticide collection tank (34), and
- disposing the slurry.
6. The process for extracting bio-pesticides from cassava bio-wastes, wherein
the method step of disposing the slurry comprises the following steps:
- separating the residual bio-wastes and hot water from the slurry obtained from jacketed processing vessel (12) by passing the slurry through the sediment water separator-cum-storage chamber (18) disposed at the bottom of the jacketed processing vessel (12),
- removing solid wastes for drying and storing for use in subsequent cattle feed enrichment, and
re-circulating separated hot water by pumping it back to a mixer-cum-grinder unit (10).
7. A bio-pesticide obtained by a process as claimed in claim 5; said bio-pesticide comprising: linamarin, lotaustralin, hydrogen cyanide and water.