Isolation,characterization and insect growth inhibitory activity of major turmeric constituents and their derivatives against Schistocerca gregaria (Forsk) and Dysdercus koenigii (Walk)

Curcuminoids, the major colouring constituents of Curcuma longa (turmeric) rhizome powder, comprise mainly three closely related curcumins (I, II and III). A simple method has been devised for their efficient extraction and separation. Their structures have been confirmed by ¹H NMR spectroscopy and unique mass fragmentation pattern. Curcumin‐I, the major constituent has been converted to five alkyl ether derivatives, which have been tested along with the parent compounds and other extractives for insect growth inhibitory activity against Schistocerca gregaria and Dysdercus koenigii nymphs. At 20 µg per nymph, benzene extract and dibutyl curcumin‐I were the most active (60% inhibition) against S gregaria, whereas at 50 µg per nymph these substances exhibited moderate growth‐inhibitory activity (45%) against D koenigii nymphs. At these concentrations, turmeric oil caused 50–60% nymphal mortality in both test insects. The insect control activity of most of the turmeric products was comparable to or better than that of a commercial neem formulation. © 2000 Society of Chemical Industry     

Effects of Thermal Conditioning and Folic Acid on Methylation of the BDNF Promoter Region in Chicks

This study aimed to investigate the effects of thermal conditioning and folic acid on the methylation levels of the avian brain-derived neurotrophic factor (BDNF) promoter region at the M3 and M9 positions in the early life of broiler chicks. In Experiment 1, male broiler chicks (day 3 of life) were orally injected with methyl cellulose solution with or without folic acid (25 mg). The chicks in the heat-treatment groups were immediately exposed to a high ambient temperature (40±0.5°C) for 12 h, while chicks in the non-heat treatment groups were left in the thermoneutral zone (30±0.5°C). The groups were as follows: 1) no thermal conditioning group without folic acid (control), 2) thermal conditioning group without folic acid, 3) no thermal conditioning group with folic acid, and 4) thermal conditioning group with folic acid. In Experiment 2, treatments were similar to those in Experiment 1, except for the usage of female chicks. After the treatments, the methylation levels of the BDNF promoter in chicks were determined using semiquantitative PCR. There were no significant differences between groups in the levels of methylation at the M3 position in both males and females as a result of thermal conditioning and folic acid treatment. Interestingly, significant effects of thermal conditioning and folic acid treatment on methylation at the M9 position were found. BDNF methylation levels at M9 significantly decreased following thermal conditioning, while folic acid suppressed demethylation in both male and female chicks. These data suggest that folic acid and thermal conditioning affects DNA methylation patterns in the central nervous system of chicks, regardless of sex.     

Use of dried papaya skin in the diet of growing pullets.

1. The chemical composition of dried papaya (Carica papaya) skin (DPS) was determined and the effect of diets containing different concentrations of this ingredient (0, 30, 60 and 90 g/kg) was studied using growing pullets as experimental animals. 2. Crude protein concentration was determined to be 229 g/kg and metabolisable energy content was estimated to be 6.4 MJ/kg. 3. Use of DPS in the diet up to 90 g/kg did not produce any significant difference in weight gain, food intake, food conversion and protein efficiency when compared with birds that received the control diet. 4. Survivability of growing pullets fed on DPS was 100%, as in the control group. 5. It was concluded that DPS can safely be used up to 90 g/kg in the diet of growing pullets.     

Assessing the bioavailability of L‐methionine and a methionine hydroxy analogue (MHA‐Ca) compared to DL‐methionine in rainbow trout (Oncorhynchus mykiss)

Different synthetic forms of supplemental methionine (Met) are produced commercially by various manufacturers. Limited information exists on the bioavailability of these different forms in commercially relevant fish species. The objective of this study was to compare the relative bioavailability of L‐methionine and a methionine hydroxy analogue calcium salt (MHA‐Ca) to DL‐methionine in a commercially relevant species, rainbow trout, using a linear slope‐ratio assay. In addition, the ability of the rainbow trout to effectively convert the D‐isomer of methionine into the biologically active L‐isomer was studied by comparing the relative bioavailability of L‐methionine to DL‐methionine. Nine (9) diets were created from a methionine‐deficient basal diet which was supplemented with graded equimolar levels of methionine (0.1%, 0.2%, 0.3% of diet by weight) from either DL‐methionine, L‐methionine and methionine hydroxy analogue calcium salt (MHA‐Ca). Diets were fed in triplicate (IBW = 24.0 ± 0.6 g) for 12 weeks using a pair‐feeding protocol. The basal diet was formulated to be deficient in both methionine (0.5%) and cysteine (0.3%), whereas meeting all other known nutritional requirements of rainbow trout. MHA‐Ca was found to be less available (P < 0.05) than DL‐methionine with relative bioavailability values of 69%, 60% and 73% based upon weight gain, growth rate (TGC) and retained nitrogen values respectively. No significant differences (P > 0.05) in bioavailability were found between DL‐methionine and L‐methionine. These findings lead to the conclusion that differences in bioavailability do exist between sources of synthetic methionine, additionally findings suggest that rainbow trout are able to effectively convert the D‐isomer of methionine into the L‐isomer without significantly affecting fish performance.     

Dietary phytase and protease improved growth and nutrient utilization in tilapia (Oreochromis niloticus × Oreochromis aureus) fed low phosphorus and fishmeal‐free diets

A 10‐week study was conducted to evaluate the effects of supplemental phytase and protease in low phosphorus (LP) and fishmeal‐free diets (FMF) on growth and nutrient utilization of tilapia. Seven isonitrogenous diets were prepared as positive control diet (PC) containing 60 g/kg fishmeal and 18 g/kg monocalcium phosphate (MCP), LP diet (12 g/kg MCP), FMF diet, LP‐FMF diet, and three enzyme diets with phytase (LP + Ph), protease (FMF + Pr), and phytase + protease (LP‐FMF + Ph + Pr) supplementation in LP, FMF and LP‐FMF diets, respectively. Weight gain, nutrient (except Ca) retention and digestibility of LP, FMF and LP‐FMF groups were lower than those of PC group (p < 0.05). Compared to LP, FMF and LP‐FMF groups, the supplementation of phytase, protease and phytase + protease improved WG by 13.2%, 11.1% and 13.0% (p < 0.05). The three enzyme groups showed higher digestibility of protein and P, and higher intestinal villus length than those of LP, FMF and LP‐FMF groups (p < 0.05), respectively. Dietary phytase and Ph + Pr also promoted the retentions of crude protein and P (p < 0.05). The results indicated that the supplementation of phytase in LP diet and protease in FMF diet improved the growth and nutrient utilization, and phytase reduced MCP inclusion in the diet of tilapia.     

Antibacterial activity and cytotoxicity of extractives from Uvaria hamiltonii stem bark

The extracts as well as piperolactum C, goniopedaline, 6beta-hydroxystigmasta-4,22-dien-3-one and a mixture of cis- and trans-4-hydroxymelleins obtained from Uvaria hamiltonii stem bark exhibited mild to moderate in vitro antibacterial activity. The results obtained were compared with a standard antibiotic, kanamycin. In a brine shrimp lethality bioassay the pet-ether, dichloromethane, methanol extracts and a major alkaloid, piperolactum C were found to exhibit mild to moderate cytotoxicity.     

Antinociceptive and antidiarrhoeal activity of Zanthoxylum rhetsa

The methanolic extract of the Zanthoxylum rhetsa Roxb. stem bark, given by oral route to mice at doses of 250 and 500 mg/kg, significantly reduced the abdominal contraction induced by acetic acid and the diarrhoeal episodes induced by castor oil in mice.     

Antimicrobial activity and cytotoxicity of Aerva lanata

Aerva lanata whole plant showed interesting antimicrobial activities (ethyl acetate and methanol extracts) and significant cytotoxic properties (petroleum ether, ethyl acetate and methanol extracts).     

Salt-tolerance in Brassica juncea L. II. Salt-stress induced changes in polypeptide pattern of in vitro selected NaCl-tolerant plants

Summary The effect of salt-stress was studied on SDS-PAGE pattern of polypeptides in seedling, leaf and siliqua tissues of four genetically stable lines (SR2P1-2, SR3P2-1, SR3P6-1 and SR3P6-2) of in vitro selected NaCl-tolerant plants, a non-selected somaclone (CP5-2) and parent variety Prakash of Brassica juncea L. Seedlings were raised in 0, 50, 100 and 150 meq/l NaCl solutions and plants were irrigated with nutrient solution with 0, 30, 60 & 90 meq/l NaCl. Salinity induced distinct genotype specific changes in polypeptide pattern of leaf and siliqua tissues, while it had no effect on the polypeptide pattern of seedlings, radicle or hypocotyl tissues in any of the lines. In leaves, at vegetative stage, a high molecular weight protein of 53.2 kD while disappered at 60 mM and higher NaCl level in cv. Prakash and SR3P2-1, it appeared in SR2P1-2 and CP5-2 only at these higher salt levels and in SR3P6 lines it was present irrespective of stress conditions. Differences were also observed for a 93.8 kD protein which appeared anew under stress in cv. Prakash, CP5-2 and SR2P1-2, while it was absent in SR-3 lines. Intensity of the 57.3 kD protein decreased in cv. Prakash, increased in SR-2 and CP-5 lines whereas remained unchanged in SR-3 lines under salt-stress. In siliquae, salt stress induced the expression of four new polypeptides (56.1–70.8 kD) at 60 mM NaCl in cv. Prakash, and at 30 mM in SR2P1-2, SR3P2-1 and SR3P6-1 lines, while these were present in CP5-2 and SR3P6-2 even in the absence of NaCl stress.