Essential Oil of Zingiber cassumunar Roxb. and Zingiber officinale Rosc.: A Comparative Study on Chemical Constituents,Antibacterial Activity,Biofilm Formation,and Inhibition of Pseudomonas aeruginosa Quorum Sensing System

Pseudomonas aeruginosa can regulate its pathogenicity via quorum sensing (QS) system. Zingiber cassumunar and Z. officinale have been used for the treatment of infectious diseases. The study aimed to evaluate and compare the chemical constituents, antibacterial, and QS inhibitor of Z. cassumunar essential oils (ZCEO) and Z. officinale essential oils (ZOEO). The chemical constituent was analysed using GC/MS. Broth microdilution and spectrophotometry analysis were used to evaluate their antibacterial and QS inhibitor activities. The main constituent of ZOEO with percent composition above 6 % (α-curcumene, α-zingiberene, β-sesquiphellandrene, and β-bisabolene, α-citral, and α-farnesene) were exist in a very minimal percentage less than 0.7 % in Z. cassumunar. All major components of ZCEO with percentages higher than 5 % (terpinen-4-ol, sabinene, γ-terpinene) were present in low proportion (<1.18 %) in Z. officinale. ZCEO demonstrated moderate antibacterial activity against P. aeruginosa. The combination of ZCEO and tetracycline showed a synergistic effect (FICI of 0.5). ZCEO exhibited strong activity in inhibiting biofilm formation. ZCEO at MIC (62.5 μg/mL) was able to reduce pyoverdine, pyocyanin, and proteolytic activity. This is the first report on the activity of ZCEO in the inhibition of P. aeruginosa QS system and it may be used to control the pathogenicity of P. aeruginosa.     

Induction of sister chromatid exchanges by heavy metal salts in root meristem cells ofAllium cepa L.

Four heavy metal salts, nickel sulphate, mercuric chloride, cadmium sulphate and zinc sulphate, were tested for induction of sister chromatid exchange (SCE) in root meristem cells ofAllium cepa. A simple modified Feulgen staining procedure was employed for SCE-analysis. Maleic hydrazide and paraquat were included for comparison. An evaluation of genotoxicity of the above test chemicals made on the basis of SCE-assay was found positive for all the test chemicals with exception of zinc sulphate which gave a weak positive result.     

Adsorption of β-amylase from Bacillus carotarum B6 onto different native starches

β-Amylase from Bacillus carotarum B₆, a soil isolate, was readily adsorbed onto native raw starch from various sources. The absorbability was highest toward arrowroot starch and was complete within 30 min of exposure. Adsorption was remarkably affected in the presence of surfactants like Tween 80.     

Changes in the Growth Hormone-IGF-I Axis in Non-obese Diabetic Mice

We investigated the changes in GH-IGF-I axis in non-obese diabetic (NOD)-mice, a model of insulin dependent diabetes mellitus. Diabetic female NOD mice and their age- and sex-matched controls were sacrificed at 4, 14, 21 and 30 days (30d DM) after the onset of glycosuria. Serum GH levels increased and serum IGF-I levels decreased in the 30d DM group (182 ± 32% and 45 ± 24% of age-matched controls respectively, p < 0.05). Another group (30d DM + I) was given SC insulin, and its serum IGF-I levels remained decreased. Liver GH receptor (GHR) and GH binding protein (GHBP) mRNA levels, as well as liver membrane GH binding assays were deeply decreased in the 30d DM group in comparison to controls. GHR message and binding capacity remained decreased in the 30d DM + I group. Renal GHR mRNA was decreased at 21d DM but not at 14d DM, whereas GHBP mRNA remained unchanged throughout the experiment. In conclusion, increased serum GH levels are documented in NOD diabetic mice, similarly to the changes described in humans. The decrease in GHR levels and decreased serum IGF-I in spite of increased circulating GH suggest a state of GH resistance.     

Sex specificity in the anal gland secretion of the Egyptian mongoose Herpestes ichneumon

The Egyptian mongoose, Herpestes ichneumon , uses its anal gland secretion to mark objects in its home range, presumably to communicate with members of its own or other groups. Chemical analysis (gas chromatography-mass spectrometry) of the secretion showed that it contained a complex mixture of long-chain (C₁₀-C₂₂) carboxylic acids with varying degrees of methyl branching. All the branched acids found in females were 4 methyl substituted. Males possess an additional component that seems to be a sex specific compound 2, 4, 6, 10 tetramethylundecanoic acid, which is a major component of the secretion.     

Clinical findings in patients with marker chromosomes identified by fluorescence in situ hybridization

Twenty-seven patients carrying marker chromosomes were previously collected, characterized by cytogenetic techniques, and identified by stepwise fluorescence in situ hybridization (FISH) with alpha-satellite DNA probes. Clinical features of 22 patients are described here and compared to other patients with marker chromosomes similarly identified and reported in the literature.     

Agonistic responses to potential co-foundresses in a cooperatively brooding quasi-social parasitoid

1. Sociality is not common among parasitoid hymenopterans, but members of the ectoparasitoid genus Sclerodermus (in the aculeate family Bethylidae) may form multi-foundress groups, producing and tending a single brood (of combined parentage) on a large host until offspring maturity. While individual foundresses can benefit more from reproducing within groups rather than alone, recent studies have indicated that there are conflicts of interest between co-foundresses at the time of host suppression and during brood production, some of which may be mediated by intrinsic or acquired dominance. Evidence for overtly agonistic interactions has, however, been lacking.
2. Here, we report that resident Sclerodermus guani Xiao et Wu females that have suppressed a host, can either accept introduced intruder females as co-foundresses without aggression or repel, and even kill, intruders by biting and stinging them.
3. Residents were more likely to exhibit aggression when they had commenced oviposition, when more days had passed since oviposition, when they were larger than the intruder, when the intruder was a non-sibling, or when they were the sole resident rather than being in a group of two residents.
4. We conclude that cooperatively brooding in Sclerodermus can be conditional on the evolutionary interests of foundresses with temporal priority on a host and their ability to repel potential co-foundresses.