Prodenia Eridania Research Articles

ChemInform Abstract: New Acylated Oleanane and Lupane Triterpenes from Gymnema sylvestre

a ) a Phytochemical investigation of the aerial parts of Gymnema sylvestre led to the isolation of two known oleanane-type triterpenes, 1 and 3, five new acylated derivatives, 2, 4, and 5 - 7, and a new lupane- type triterpene, 8. The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D- and 2D-NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds. Introduction. - Gymnema sylvestre (Asclepiadaceae), a vulnerable species, is a slow-growing, perennial woody climber in tropical and subtropical regions (1). It is a potent antidiabetic plant and used in folk, ayurvedic, and homeopathic systems of medicine (2 - 5). It is also used in the treatment of asthma, eye complaints, inflammations, family planning, and snake bite (6 - 9). In addition, it possesses antimicrobial, antihypercholesterolemic (10), hepatoprotective (11), and sweet-sup- pressing activities (12). It also acts as feeding deterrents to caterpillar, Prodenia eridania (13), prevents dental caries caused by Streptococcus mutans (14), and it is used in skin cosmetics (15). The various reports on its multiple uses attracted attention for utilization of the plant for gynmemic acid (active principle). From the organic extract of G. sylvestre, we had isolated oleanane and lupane triterpenes (16). In the continuing the investigation of G. sylvestre, we have isolated two known oleanane-type triterpenes, 1 and 3, one obtained for synthesis, 2, four new acylated derivatives, 4 - 7, and a new lupane-type triterpene, 8. Results and Discussion. - Compound 1 was identified as (3b,16b)-olean-12-ene- 3,16,23,28-tetrol by comparison of its spectral data with those in the literature (17). Compound 2 had the molecular formula C38H58O8 on the basis of the quasi- molecular-ion peak at m/z 643.4204 ((M þ H) þ ) in the HR-ESI-MS spectrum and 13 C-NMR data. The 1 H-NMR spectra (Table 1) revealed the presence of two O-bearing CH and two O-bearing CH2 groups assigned by a HSQC experiment. The high chemical-shift values and the presence of four singlets, at d(H) 2.00 and 2.01, and 2.03 and 2.05 indicate that the carbinol functions are acetylated. The configurations of the O-bearing C-atoms have been deduced from a NOESY experiment, where the H-atom HC(3) showed a NOE effect with the H-atoms of CH2(23), and H-atoms of Me(24)

The Role of the Tympanal Membranes in the Tuning of Auditory Receptors in Tettigoniidae (Orthoptera: Ensifera)

ABSTRACT One of the fundamental problems in auditory research is the origin of the frequency selectivity of auditory receptors. Horridge (1960) demonstrated that the auditory interneurones in locusts were tuned to different sound frequencies, thus suggesting that the auditory receptors were frequency selective. Michelsen (1968, 1971) established that the auditory organ of locusts contained four groups of receptors with different characteristic sound frequencies and proposed that the frequency selectivity of the individual groups was dependent on the resonant properties of the tympanum. Investigation using the more sensitive of the two auditory receptors in the moth Prodenia eridania extended this proposal by suggesting that the tuning of this receptor depended on both resonant properties of the auditory organ (scoloparium) and filtering properties of the acoustic system (Adams, 1972), the most important factor in the latter being the tympanal membranes. In crickets and bushcrickets, however, the tympanal membranes vibrate in a simple mode for a wide band of sound frequencies (Paton, Capranica, Dragsten & Webb, 1977; Michelsen & Larsen, 1978), thus making it unlikely that the motion of the tympanum is responsible for the frequency selectivity (Zhantiev & Korsunovskaya, 1978; Esch, Huber & Wohlers, 1980) of the individual auditory receptors. Similarly, Ball & Hill (1978) demonstrated that auditory intemeurones of larval instar crickets are tuned even though they have no tympanal membranes. A recent study of the tonotopic organization of the auditory organ in bushcrickets (Oldfield, 1982) revealed that the auditory receptors remained tuned after the removal of one tympanum. This result, like those obtained from crickets, suggests that the resonant properties of the tympanal membranes are not responsible for the tuning of the individual auditory receptors. Conclusive evidence on this proposal, however, requires the removal of both tympanal membranes, thus eliminating the possibility that the remaining tympanum in the study by Oldfield (1982) determined the tuning of the auditory receptors.

Evaluation of six insect pests for transmission of potato spindle tuber viroid

Six insect pests of potato, green peach aphid,Myzus persicae (Sulzer); potato leafhopper,Empoasca fabae (Harris); Colorado potato beetle,Leptinotarsa decemlineata (Say); tarnished plant bug,Lygus lineolaris (Palisot de Beauvois); red-legged grasshopper,Melanoplus femurrubrum (DeGeer); and southern army worm,Prodenia eridania (Cramer), were tested for their ability to transmit potato spindle tuber viroid (PSTV). PSTV infection was determined by a gel electrophoretic assay made 6 weeks after transfer of insects from infected to non-infected plants of the cultivar, ‘Katahdin.’ Plants grown from tubers of the original non-infected hosts were also assayed. PSTV was detected in only 2 of 183 test plants; these 2 plants had been infested with the tarnished plant bug. These results suggest that the insect species studied are relatively insignificant as vectors of PSTV.

Epoxide hydrase activity and its relationship to development in the southern armyworm, Prodenia eridania

Enzymatic epoxide hydration of the cyclodiene insecticide HEOM by the southern armyworm was investigated throughout the late larval, pupal and adult stages of development. Epoxide hydrase activity reaches a maximum in the period between ecdysis of the last instar and the larval-pupal ecdysis, decreases during pupal life and becomes essentially zero following adult emergence. Comparison was made with variations occurring in juvenile hormone hydrase activity, and the significance of these age-dependent changes in relation to regulation of insect development are discussed.

Properties of 5-aminolaevulinate synthetase and its relationship to microsomal mixed-function oxidation in the southern armyworm (Spodoptera eridania)

1. Activity of 5-aminolaevulinate synthetase was measured in the midgut and other tissues of the last larval instar of the southern armyworm (Spodoptera eridania Cramer, formerly Prodenia eridania Cramer). 2. Optimum conditions for measuring the activity were established with respect to all variables involved and considerable differences from those reported for mammalian enzyme preparations were found. 3. Maximum activity (20 nmol/h per mg of protein) occurs 18-24 h after the fifth moult and thereafter decreases to trace amounts as the larvae age and approach pupation. 4. Synthetase activity was rapidly induced by oral administration (in the diet) of pentamethylbenzene, phenobarbital, diethyl 1,4-dihydro-2,4,6-trimethylpyridine-3, 5-dicarboxylate, and 2-allyl-2-isopropylacetamide. 5. Puromycin inhibited the induction of synthetase by pentamethylbenzene. 6. Induction of 5-aminolaevulinate synthetase correlated well with the induction of microsomal N-demethylation of p-chloro-N-methylaniline, except for phenobarbital, which induced the microsomal oxidase relatively more than the synthetase.

Inhibition of the enzymatic hydration of the epoxide HEOM in insects

Enzymatic epoxide hydration, a significant mechanism in the regulation of insect development and in the detoxication of certain cyclodiene insecticides, has been investigated in vitro in the blowfly, Calliphora erythrocephala, the southern armyworm, Prodenia eridania, and the Madagascar cockroach, Gromphadorhina portentosa. Characterization of the hydrases involved in cyclodiene epoxide hydration has been achieved using as substrate a cyclodiene insecticide (HEOM) susceptible to enzymatic epoxide ring cleavage. The enzymes, which are microsomal but different from the oxidases, are inhibited in varying degrees by microsomal oxidase inhibitors as well as by certain epoxides, esterase inhibitors and compounds with reported juvenilizing ability. Group-bulk and electronegative effects are important requirements for HEOM-hydrase inhibition, the best inhibitor of the system being 1,1,1-trichloro-2,3-epoxypropane. Differences between the structural requirements for HEOM-hydrase inhibition and those for inhibition of the epoxide hydrase responsible for the degradation of juvenile hormone are discussed.

Degradation and conjugation of Cecropia juvenile hormone by the southern armyworm (Prodenia eridania)

1.1. The degradation of Cecropia juvenile hormone by prodenia eridania occurs via two major pathways.2.2. Ester hydrolysis can either precede or succeed epoxide cleavage.3.3. The responsible esterase and epoxide hydrase are found in a number of tissues.4.4. The final degradative products is an acid-diol that is conjugated and excreted as the sulphate.

Structure-activity relationships in the effects of 1-alkylimidazoles on microsomal oxidation in vitro and in vivo

The inhibitory activity of a series of 13 1-alkylimidazoles toward microsomal epoxidation of aldrin in enzyme preparations from rat liver and armyworm ( Prodenia eridania) gut is optimal in compounds with a chain length of 8–10 carbon atoms. The capacity of the imidazoles to bind to cytochrome P-450 (type II) appears to be closely related to their inhibitory activity. The activity of the compounds in vivo in synergizing the toxicity of carbaryl to houseflies and potentiating pentobarbital sleeping time in mice closely parallels the data in vitro. Regression analyses clearly establish that both activity patterns in vitro and in vivo can be satisfactorily described by linear equations in terms of the hydrophobic bonding constant (π and π 2) indicating a close correlation between biological activity and lipophilic character.

Gymnemic acids: Secondary plant substances of dual defensive action?

Gymnemic acids, the triterpene saponins from the leaves of the asclepiad vine Gymnema sylvestre, act as feeding deterrents to a caterpillar, Prodenia eridania. The effect is demonstrable with sugar-free diets, suggesting that the acids do not act, as they do in mammals, by suppressing the sweetness of sugars.

Induction of microsomal enzymes in the southern armyworm ( Prodenia eridania)

Levels of microsomal epoxidation, N-demethylation, and cytochrome P-450 in the gut tissues of sixth instar southern armyworm larvae were considerably enhanced following oral in vivo treatment with a series of methylbenzenes. Induction increased with increasing methyl substitution and was maximal with pentamethylbenzene. The increase in microsomal activity occurred rapidly after initiation of treatment and the final levels of induction achieved were dependent on the concentration of the inducer in the diet and the time of exposure. Microsomal enzyme activity returned to control levels following termination of exposure and induction was blocked by puromycin and cycloheximide but not by actinomycin D. The in vivo tolerance of induced worms to orally administered carbaryl was increased in a manner reflecting the enhanced microsomal enzyme activity.

Chemical Defence in Central American Non-Ant-Acacias

On the basis of their association with ants, neotropical species of the genus Acacia may be grouped into two broad categories. 'Ant-acacias', comprising less than 10% of the species in Central America depend in varying degree on a mutualistic association with ants of the genus Pseudomyrmex. The plants provide their ants with shelter in swollen stipular spines and with nourishment from foliar nectaries and nutritive structures (Beltian bodies) at the leaf tips. The ants in turn provide for the plants' protection against mammalian and insect herbivores and against neighbouring plant competitors (Belt 1874; Brown 1960; Janzen 1966, 1967). Janzen (1967) has demonstrated that Acacia cornigera (L.) Willd. plants cannot survive after experimental removal of their associated ant colonies. The remaining species of Acacia in Central America comprise the second group, the 'non-ant-acacias'. These plants do not harbour mutualistic ant colonies, nor do they possess the various morphological features of acacias with such colonies. Survival of non-ant-acacias is presumably dependent, therefore, on other means of defence against herbivores. After noting that the foliage of non-ant-acacias was markedly bitter to human taste, whereas that of ant-acacias was mild-tasting, Janzen (1966) proposed the following hypotheses: (i) non-ant-acacias are protected from herbivores by the presence in their foliage of toxic or repellant chemicals; (ii) symbiosis with ants has been evolved by antacacias as an alternative means of protection; and (iii) chemical defence has subsequently been lost in the ant-acacias, possibly because maintenance of both ant and chemical defence places an unnecessary metabolic burden on the plant. In the present paper we present evidence in favour of these hypotheses. For experiments in the laboratory we selected A. cornigera, an ant-acacia, A. farnesiana (L.) Willd., a non-ant acacia, and A. chiapensis Saff., a species showing intermediate characteristics. A. cornigera and A. farnesiana are widely distributed through Central America, but A. chiapensis is very limited in distribution. Plants of A. chiapensis are normally found in nature in association with ant colonies, yet they can survive in the absence of ants; therefore, this species will be regarded as a non-ant-acacia for the purposes of this study. Since insects known to attack unoccupied ant-acacias in Central America were unavailable for our work, the southern armyworm, Prodenia eridania (Cramer) (Noctuidae), was selected for bioassay of the acacias. The caterpillar of this species is highly polyphagous with an outstanding ability to detoxify insecticides (Krieger 1970; Krieger & Wilkinson 1969) and, presumably, toxic compounds encountered in its wide array of food plants

Enzymic sulphation of p-nitrophenol and steroids by larval gut tissues of the southern armyworm (Prodenia eridania Cramer)

1. An enzyme system that catalyses the sulphation of p-nitrophenol, cholesterol, alpha-ecdysone, beta-sitosterol, dehydroepiandrosterone, oestrone and four other steroids of plant and insect origin was obtained from the soluble fraction of southern-armyworm gut tissues. 2. The enzyme system required ATP and inorganic sulphate, and activity was slightly enhanced in the presence of GSH. 3. The properties of this enzyme system with respect to pH, temperature, substrate and protein concentrations and various cofactors and reagents were studied. At -23 degrees C the enzyme preparation could be stored for 2 weeks without drastic loss of activity. At the end of storage for 1 month the loss of activity was approx. 21%. 4. The possible involvement of this enzyme system in insect endocrine control is discussed.

Haemolymph lipids and fat body lipases of the southern armyworm moth

The haemolymph lipid of the southern armyworm moth, Prodenia eridania, is chiefly diglyceride with smaller amounts of triglyceride, monoglyceride, and free fatty acid also present. The stored lipid of moth fat body is almost all triglyceride. Although flight muscle contains a very active monoglyceride lipase, its ability to hydrolyse tri- and diglycerides is very low. The fat body contains enzymes able to hydrolyse tri-, di-, and monoglycerides. These data do not support the suggestion that fat body triglyceride is converted to diglyceride, which is carried in the haemolymph to the flight muscle and then hydrolysed to free fatty acid for oxidation during flight; rather, they indicate that triglyceride can be completely hydrolysed in the fat body, and the resulting free fatty acid is carried to the flight muscle to provide energy for flight.

Preference of Campoletis perdistinctus for Certain Noctuid Larvae123

Mated adult females of Campoletis perdistinctus (Viereck) were confined together in one or more of 4 laboratory tests and I field-cage test with 3- to 4-day-old larvae of the noctuids: beet armyworm, Spodoptera exigua (Hubner); bollworm, Heliothis zea (Boddie); cabbage looper, Trichoplusia ni (Hubner); fall armyworm, Spodoptera frugiperda (J. E. Smith); southern armyworm, Prodenia eridania (Cramer); tobacco bud worm, H. virescens (F.); and yellowstriped armyworm, Prodenia ornithogalli Guenee. The bollworm, fall armyworm, and tobacco budworm were the most preferred hosts in all laboratory tests, whereas the cabbage looper was the least preferred host, and no parasite cocoons were produced from larvae of the beet armyworm. Also, rates of parasitization were greater when the hosts were confined in chambers containing cotton plants than in chambers containing an artificial diet. In the field-cage test, considerably more parasite cocoons were formed from larvae of the bollworm and the tobacco bud worm than from the cabbage looper and the southern armyworm. Thus, laboratory and field-cage tests indicated that the bollworm and tobacco budworm were among the most preferred noctuid hosts of C. perdistinclus . Consequently, these noctuids should be the major ovipositional site [or the parasite if it were to be used in an inundative release program against cotton pests.

Conjugation of p-nitrophenol with sulfate in larvae of the southern armyworm ( Prodenia eridania)

Of a dose of 14C- p-nitrophenol administered orally to sixth-instar larvae of the southern armyworm ( Prodenia eridania) 17–25% was recovered from the excreta as the sulfate ester during the first 48 hr after treatment. Unchanged 14C- p-nitrophenol accounted for a further 7% of the applied dose and the remaining radioactivity was in some form which was apparently bound tighly with plant pigments. No evidence was obtained for the presence of 14C- p-nitrophenyl β- d-glucoside of 14C- p-nitrophenyl phosphate in the armyworm fecal extract.

Mechanism of inhibition of microsomal mixed-function oxidation by the gut-contents inhibitor of the southern armyworm (Prodenia eridania).

A potent inhibitor of microsomal mixed-function oxidation reactions in insects had previously been isolated and partially purified from the gut contents of Prodenia eridania and shown to be associated with proteinase activity. Incubation of rat liver microsomal fraction with low concentrations of this inhibitor led to solubilization of NADPH-cytochrome c reductase, which was paralleled by the inactivation of reduction of cytochrome P-450 by NADPH and by the inhibition of NADPH-linked benzo[3,4]pyrene hydroxylation and aminopyrine demethylation. There was little or no effect on cytochromes b(5) and P-450, nor was the capacity of the latter catalyst to combine with exogenous substrates decreased. Contrary to the findings with NADPH, preincubation of microsomal fraction with the inhibitor did not cause a significant decrease in the rate of cytochrome P-450 reduction by NADH, supporting the assumption that different catalysts are involved in the electron transfer from NADH and NADPH to cytochrome P-450. The findings indicate the importance of taking the possible presence of endogenous inhibitors into consideration when evaluating low or absent mixed-function oxidation activities found in insect systems in vitro.

Sex pheromones of the southern armyworm moth: isolation, identification, and synthesis.

Two sex pheromones have been isolated from the female southern armyworm moth, Prodenia eridania (Cramer), and identified as cis-9-tetradecen-1-ol acetate, identical with the sex pheromone of the fall armyworm moth, Spodoptera frugiperda (J. E. Smith), and cis-9,trans-12-tetradecadien-1-ol acetate.

Mechanical Tuning of the Acoustic Receptor Organ of the Noctuid Moth

Mechanical characteristics of the auditory organ of Noctuid moths (Prodenia eridania, Cramer) have been investigated in an effort to define the stimulus at the receptor organ. This organ contains two receptor cells of unequal sensitivity and is suspended from the tympanic membrane. The neural spike rates produced by the more sensitive of the two cells have been recorded as a function of vibration frequency while mechanically stimulating the tympanic membrane. The frequency characteristic obtained in this way is determined by the mechanical properties of the receptor organ itself and is not affected by the system of air-filled cavities surrounding it. The resulting characteristic shows a primary resonance near 2 kHz, an antiresonance near 10 kHz, and one or more higher order resonances above 10 kHz. When the tympanic membrane is exposed to acoustic waves so that the intratympanic cavities become effective, the hearing organ is most sensitive to sound frequencies between 25 and 60 kHz [K. D. Roeder, J. Insect Physiol. 12, 843 (1966)]. Thus it appears that the primary mechanical resonance at 2 kHz is attenuated by the acoustic cavity system. The remaining high-frequency response is adapted to the frequency range of the sonar signals of bats.

Hosts and Host-Age Preference of Campoletis perdistinctus12

According to our review of the literature, 23 species of Lepidoptera have been reported as hosts of the ichneumonid wasp Campoletis perdistinctus (Viereck). However, in laboratory tests, the parasite developed successfully on 4 additional species, the armyworm, pseudaletia unipuncta (Haworth); the cabbage looper, Trichoplusia ni (Hubner); the southern armyworm, Prodenia eridania (Gramer); and the western yellow-striped armyworm, P. praefica Grote. Two-to 4-day-old larvae of the alfalfa looper, Autogropha californica (Speyer), the bollworm, Heliothis zea (Boddie); the cabbage looper; the fall armyworm, Spodoptera frugiperda (J. E. Smith); the southern armyworm; the tobacco budworm, H. virescens (F.); and the variegated cutworm, Peridroma saucia (Hubner), were particularly susceptible to parasitism by C. perdistinctus in the laboratory. The parasite stung 1- to 8-day-old host larvae but preferred 2- to 4-day-old larvae. The fall armyworm appeared to be the best host for mass rearing the parasite.

An endogenous inhibitor of microsomal mixed-function oxidases in homogenates of the southern armyworm (Prodenia eridania).

1. A potent inhibitor of microsomal mixed-function oxidation has been isolated from the gut contents of larvae of the southern armyworm (Prodenia eridania). 2. Progressive inhibition is associated with a soluble proteinase with a molecular weight of approx. 26000. 3. Although the proteolytic activity of the inhibitor can be reduced by phenylmethanesulphonyl fluoride and other reagents, these materials are only partially effective in protecting the microsomal enzymes. 4. Inhibitory activity is decreased in the presence of bovine serum albumin.