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Phytochemical investigation led to the isolation of three alkaloids [skimmianine (1), vulcanine (2) and evoxine (3)] from the aerial parts of Haplophyllum tuberculatum, and two diacetylenic spiroketal enol ethers [spiroketalenolether polyyne (4) and [7-hexa-2,4-diynylidene-1,6-dioxaspiro[4.4]nona-2,8-dien-4-yl] acetate (5)] and a sesquiterpene lactone [8α acetoxy-11β,13dihydrokauniolide (6)] from the aerial parts of Chrysanthemum coronarium. The chemical structures of the isolated compounds were determined by using spectral data of 1H NMR, 13C NMR, as well as by comparison with literature data. Compounds 4, 1 and 5 were the most potent inhibitors against plant pathogenic bacteria Rhizobium radiobacter, Ralstonia solanacerum and Pectobacterium carotovorum ss. carotovorum with minimum inhibitory concentration (MIC) values of 31.3, 62.5 and 31.3 µg/ml, respectively. In antifungal assay, compounds 1 (MIC 62.5 µg/ml), 2 (MIC 62.5 µg/ml) and 5 (MIC 125 µg/ml) caused the highest inhibitory effects against phytopathogenic fungi Verticillium dahliae, Fusarium oxysporum and Alternaria solani, respectively. Moreover, crude extract of H. tuberculatum and 4 were significantly the most potent inhibitors of seed germination, root and shoot growth of Echinochloa crus-galli.

This study was undertaken to evaluate the herbicidal activity of twelve natural compounds belonging to monoterpenes, phenylpropenes, and sesquiterpenes against Echinochloa crus-galli under laborato...

Introduction: The surgeons face challenges to restore and align the nasolabial and alveolar structures to the normal state making primary closure of the lip for unilateral cleft lip and palate (UCLP) very difficult. Nasoalveolar molding (NAM) represents a paradigm shift from the traditional methods of presurgical infant orthopedics (PSIO).Objective: To study the outcomes of NAM therapy for the correction of maxillary arch alignment, decreasing the cleft gap severity and improving the nasal esthetics.Material and methods: 12 UCLP infants (age < 1month) were presented for NAM therapy prior to surgical intervention. NAM appliance was constructed as two connected parts; intraoral plate for alveolar molding and nasal stent for nasal molding. Incremental addition and reduction to the appliance were performed to realign the deformed nasoalveolar structure. Measurements of intraoral and nasal casts were made, and statistical analyses were performed to compare the between pre and post NAM measurements.Results: After NAM therapy there was a statistical significant decrease in intersegment distance, midline deviation, alar width. There was also a statistical significant increase in columellar length and angle.Conclusion: By the selective realignment of UCLP nasoalveolar deformity, NAM therapy can achieve a foundation for more esthetic repair under minimal tension.

Microbial exopolysaccharides (EPS) are high molecular weight polymers having different sugar residues. EPS have potential applications in different fields, such as medicine, food and environment. Therefore, there is a growing interest in production, characterization and application of EPS from different microorganisms. The present study designed to investigate the production and characterization of EPS from Rhodotorula mucilaginosa YMM19 isolated from Morus nigra L. fruits as well as to examine their potential emulsifying properties. Effect of NaCl concentration, incubation period and pH on the production of EPS was studied. The maximum EPS production by yeast was achieved at 10% NaCl (9741.84 mg/l). The best incubation time for production of EPS was 5 days. Production of EPS decreased under neutral condition and increased at acidic and alkaline condition. The structural feature of EPS was examined by FT-IR and NMR spectral analysis and confirmed the presence of glucose, glucopyranose and galactose. The isolated EPS showed higher emulsification capacity with emulsification activity of 71% and emulsifying index of 60%. The EPS gave strong emulsification for farnesol and was more effective than sodium dodecyl sulphate, a reference emulsifier, in enhancing the herbicidal activity of farnesol against Melilotus indicus under greenhouse condition. The results suggest that the EPS produced by YMM19 strain has a potential to be used as emulsifying agent in pesticide formulations.

Microbial exopolysaccharides (EPS) are high molecular weight polymers having different sugar residues. EPS have potential applications in different fields, such as medicine, food and environment. Therefore, there is a growing interest in production, characterization and application of EPS from different microorganisms. The present study designed to investigate the production and characterization of EPS from Rhodotorula mucilaginosa YMM19 isolated from Morus nigra L. fruits as well as to examine their potential emulsifying properties. Effect of NaCl concentration, incubation period and pH on the production of EPS was studied. The maximum EPS production by yeast was achieved at 10% NaCl (9741.84 mg/l). The best incubation time for production of EPS was 5 days. Production of EPS decreased under neutral condition and increased at acidic and alkaline condition. The structural feature of EPS was examined by FT-IR and NMR spectral analysis and confirmed the presence of glucose, glucopyranose and galactose. The isolated EPS showed higher emulsification capacity with emulsification activity of 71% and emulsifying index of 60%. The EPS gave strong emulsification for farnesol and was more effective than sodium dodecyl sulphate, a reference emulsifier, in enhancing the herbicidal activity of farnesol against Melilotus indicus under greenhouse condition. The results suggest that the EPS produced by YMM19 strain has a potential to be used as emulsifying agent in pesticide formulations.

Twenty-eight compounds were isolated from endophytic, soil and marine fungi and their structures were elucidated through spectroscopic methods. The isolated compounds were tested for their antibacterial and herbicidal activities against phytopathogenic bacteria and barnyard grass weed for the first time. Methyleurotinone (14) was the most potent compound against Pectobacterium carotovorum subsp. carotovorum, Pseudomonas syringae pv. syringae, Rhizobium radiobacter and Ralstonia solanacearum with minimum inhibitory concentration (MIC) values of 31.3, 125, 31.3 and 125 mg/L, respectively. Compounds 13–15 were highly effective in reducing the development of potato tuber soft rot disease caused by P. carotovorum subsp. carotovorum. Furthermore, twelve of the tested compounds induced a significant reduction in seed germination of Echinochloa crus-galli at 2 mM with compounds 8 and 26 causing complete inhibition of seed germination. Also, compounds 4, 22, 5, 8, 18 and 25–27 induced remarkable reduction of root and shoot growth of E. crus-galli at 2 mM.

Six monoterpenes, ((−)-citronellal, p-cymene, (−)-menthone, α-pinene, α-terpinene and (−)-terpinen-4-ol) and two phenylpropenes, (trans-cinnamaldehyde and eugenol) were tested for their insecticidal activity against the rice weevil, Sitophilus oryzae under laboratory conditions. The bioassays were carried out on wheat at the concentrations of 0.5, 1.0 and 5.0 g/kg. Adult mortality was assessed after 14 days of exposure. After this interval, the treated wheat was retained for an additional period of 90 days, in order to evaluate progeny production and wheat loss. At the concentrations of 0.5 and 1.0 g/kg, trans-cinnamaldehyde and eugenol achieved highest adult mortality. At 5.0 g/kg, all compounds except for p-cymene and α-pinene caused complete (100%) adult mortality. Generally, trans-cinnamaldehyde was the most potent compound causing complete inhibition of progeny at the three concentrations. Similarly, no progeny were observed in the wheat treated with (−)-citronellal, eugenol, p-cymene, (−)-menthone, and (−)-terpinen-4-ol at 5.0 g/kg after 45 and 90 days. Similar trends were noted for wheat weight loss and damage as the treatment with monoterpenes and phenylpropenes at the highest rate preserved the wheat intact and free from damage by S. oryzae for 90 days. Our findings suggest the tested compounds except p-cymene and α-pinene could be recommended for use as part of an integrated pest management program for S. oryzae control in stored wheat.

In the present study, six monoterpenes [(−)-citronellal, p-cymene, (−)-menthone, α-pinene, α-terpinene, and (−)-terpinen-4-ol] and two phenylpropenes [trans-cinnamaldehyde and eugenol] were evaluated for their contact and fumigant toxicities against Sitophilus oryzae adults. The effects of these compounds on the mortality of S. oryzae adults in stored wheat and their inhibitory effects on acetylcholinesterase (AChE) and adenosine triphosphatases (ATPases) were examined. The tested compounds showed varying degrees of contact toxicity, with trans-cinnamaldehyde (LC50 = 0.01 mg/cm2) being the most potent compound, followed by (−)-menthone (LC50 = 0.013 mg/cm2) and eugenol (LC50 = 0.015 mg/cm2). In a fumigant toxicity assay, the monoterpenes α-terpinene, p-cymene, and (−)-menthone showed the highest toxicities (LC50 = 50.79, 52.37, and 54.08 μl/L air, respectively). Trans-cinnamaldehyde, (−)-citronellal, and eugenol were the least toxic (LC50 > 100 μl/L air). In general, the oxygenated compounds exhibited high contact toxicities while the hydrocarbon compounds exhibited high fumigant toxicities. When tested for their insecticidal activities against S. oryzae in stored wheat, trans-cinnamaldehyde was found to be the most potent compound, with 73.9% mortality at an application rate of 0.5 g/kg and complete mortality (100%) at 1 and 5 g/kg after 1 week of treatment. All of the tested compounds showed AChE inhibition, although (−)-citronellal and trans-cinnamaldehyde presented the strongest enzyme inhibition, with IC50 values of 18.40 and 18.93 mM, respectively. On the other hand, (−)-terpinene-4-ol exhibited the highest inhibition of ATPases, followed by α-pinene and α-terpinene.

In this study, 18 plant growth-promoting bacterial (PGPB) strains were isolated from the rhizosphere of both Red silk-cotton tree (Bombax malabaricum) and Chinese banyan (Ficus retusa). Culture morphology was observed and genotypic characterization was accomplished by sequencing partial 16S rRNA gene. Plant growth promotion traits and antagonistic activities of the strains against phytopathogenic fungi were evaluated. Among all strains, Bacillus thuringiensis (MN419208) exert the highest indole acetic acid (38 µg/ml), produced exopolysaccharides (587.2 µg/ml), and fixed nitrogen which in turn increased both fresh and dry weights of bean plants by 41.5% and 18.8%, respectively. In another greenhouse experiment studying the antifungal activities of seven strains and their co-culture against Rhizoctonia solani (LN735538), B. sonorensis MN419205, B. wiedmannii MN419207, B. subtilis MN419218, and the mixture of (MN419207) and (MN419208) reduced total damping off from 81.7% in control to 30%, 35%, 35%, and 38.3%, respectively, and reduced disease severity index from 33.3% to 20.5%, 22.5%, 14.2%, and 19.3% as well. Our data indicate that these strains are effective in promoting plant growth and in inhibiting R. solani infection nonetheless field experiments are needed to examine their effectiveness as a viable alternative to chemical fertilizers and conventional pesticides.

Monoterpenes, the major constituents of essential oils, are known for their diverse biological activities. This study was conducted to assess the herbicidal effect of six monoterpenes viz. (R)-carvone, 1,8-cineole, cuminaldehyde, (S)-fenchone, geraniol, (S)-limonene, and (R)-linalool on barnyardgrass under laboratory and glasshouse conditions with a view to explore the possibility of their utilization for future weed management. The effect of monoterpenes on chlorophyll contents and total phenolic compounds was also evaluated. The inhibitory effects of monoterpenes on seed germination and seedling growth were tested at concentrations of 1, 2, 4, 6, and 8 mM. The results showed that geraniol and (R)-carvone caused greatest reduction of seed germination with complete inhibition at the concentrations > 2 mM. Similarly, these two compounds were the most potent inhibiters for root and shoot growth. In general, monoterpenes were less effective against seed germination than seedling growth. Furthermore, the inhibition of root growth by all compounds was greater than that of shoot growth. In foliar application treatments under glasshouse conditions, the monoterpenes reduced the fresh and dry weights, and shoot length of two-leaf stage barnyardgrass at concentrations of 1 and 2%. In addition, the tested monoterpenes caused phytotoxicity symptoms, mainly chlorosis and necrosis, followed by weed death. Complete weed control was observed in the treatments with 1 and 2% of geraniol, and 2% of cuminaldehyde. Further, a reduction of chlorophyll contents and total phenolic compounds of barnyardgrass leaves was noticed, indicating that the monoterpenes cause adverse effect on photosynthesis and weed metabolism. Based on the results of this study, it can be concluded that the monoterpenes, particularly geraniol, (R)-carvone, and cuminaldehyde, can be used as potential natural herbicides.

The main objectives of the present study are to introduce new, ecologically safe, and natural compounds for controlling red flour beetle, Tribolium castaneum, and to understand the possible mode of action of these compounds. Therefore, the insecticidal and repellent activities of two phenylpropenes and six monoterpenes have been evaluated against the adults of T. castaneum. The inhibitory effects of these compounds on the activity of adenosine triphosphatases (ATPases) and acetylcholinesterase (AChE) were also tested. In fumigant toxicity assay, (−)-terpinen-4-ol (LC50 = 20.47 μl/l air) and α-terpinene (LC50 = 23.70 μl/l air) exhibited the highest toxicity without significant differences between them. Moreover, (−)-menthone and p-cymene showed strong toxicity, while (−)-citronellal, trans-cinnamaldehde, and eugenol were not active. In contact toxicity assay, the two phenylpropenes, trans-cinnamaldehde and eugenol, had the highest toxicity with same LC50 value of 0.02 mg/cm2. The monoterpenes and phenylpropenes showed pronounced repellent effect on the adults of T. castaneum at 0.001 mg/cm2 with (−)-menthone, trans-cinnamaldehyde, and α-terpinene being the most effective after 2 h of exposure. Repellent activity depended on compound, exposure time, and concentration. On the other hand, the tested compounds exhibited strong inhibition of ATPases form the larvae of T. castaneum as their IC50 values ranged between 1.74 and 19.99 mM. In addition, (−)-citronellal (IC50 = 9.82 mM) and trans-cinnamaldehde (IC50 = 23.93 mM) caused the highest inhibitory effect on AChE, while α-pinene (IC50 = 53.86) and p-cymene (IC50 = 68.97 mM) showed the weakest inhibitory effect. The results indicated that the tested phenylpropenes and monoterpenes had the potential to be developed as natural insecticides and repellents for controlling T. castaneum.

Six phragmalin limonoids, named tabulalin and tabulalides A-E, were isolated from the root bark of Chukrasia tabularis (Meliaceae). Their structures were determined by spectroscopic methods, and their antifeedant properties evaluated.

Three novel ring D opened limonoids corresponding to the phragmalin 8,9,14-orthoacetate with the addition of methyl 2,30-orthoacetate or a propionate, swietenialides A, B, and C and two ring-D opened phragmalin-type 1,8,9-orthoacetates, swietenialides D and E, were isolated together with one known mexicanolide, 2-hydroxyswietenin, from the ether extract of the stem bark of Swietenia mahogani JACQ. (Meliaceae). The structure of these unique compounds was elucidated by spectroscopic means.

Three new mexicanolide-type limonoids were isolated together with two known mexicanolides, 2-hydroxyswietenin and swietemahonin G, from the ether extract of the stem bark of Swietenia mahogani JACQ. (Meliaceae). The structure of these compounds was elucidated by spectroscopic means and their biological activities were also tested.

The objectives of this study were to determine the qualitative production of extracellular enzymes produced by ten endophytic fungi and to investigate their antifungal potential against some phytopathogenic fungi namely, Alternaria alternata, Botrytis cinerea, Fusarium oxysporum and Rhizoctonia solani. In addition, the endophytic fungal isolates were screened for enzyme production by plate assay method. All endophytic fungi were able to produce proteases and cellulases with different levels except Alternaria alternata. Meanwhile, Fusarium, Alternaria, Nigrospora and Phoma species produced amylase. None of the tested endophytic fungi showed laccase production. Endophytic fungi filtrates revealed variable antifungal activities against the tested phytopathogenic fungi with Curvularia lunata filtrate being the most effective. This filtrate induced 48% and 80% growth inhibition of B. cinerea and R. solani, respectively. The phytochemical analysis of the endophytic fungi crude extract disclosed the presence of alkaloids and terpenoids. Morphological observations by optical microscope showed uncommon hyphal deformation and enlargement of cytoplasmic vacuoles of R. solani when treated with C. lunata filtrate. Furthermore, C. lunata (hyphal suspension and filtrate) was examined to control root rot caused by R. solani on faba bean plants in vivo. Both antagonistic treatments significantly reduced root rot severity., Les objectifs de cette étude étaient de déterminer la production qualitative des enzymes extracellulaires de dix champignons endophytes et d’étudier le potentiel antimicrobien de leurs filtrats sur certains champignons phyto-pathogènes. Les dosages enzymatiques ont démontré qu’il y avait une variation dans la production de différentes enzymes extracellulaires parmi les champignons endophytes testés. Tous les champignons endophytes étaient capables de produire des protéases et de la cellulase avec des niveaux différents sauf Alternaria alternata. Pourtant, les espèces Fusarium, Alternaria, Nigrospora et Phoma étaient capables de produire l’amylase. Aucun des champignons endophytes testés n’a produit de laccase. Les filtrats de champignons endophytes ont révélé des activités antifongiques variables contre les champignons phytopathogènes testés, dont le plus efficace était le filtrat de Curvularia lunata. Ce filtrat a induit une inhibition de croissance de 48 % et 80 % de Botrytis cinerea et Rhizoctonia solani respectivement. L’analyse phytochimique de l’extrait brut de champignons endophytes a révélé la présence d’alcaloïdes et de terpénoïdes. Les observations morphologiques au microscope optique ont montré une déformation hypale et un élargissement des vacuoles cytoplasmiques de R. solani lorsqu’il est traité avec du filtrat de C. lunata. De plus, C. lunata (suspension d’hypales et filtrat) a été examiné pour lutter contre la pourriture des racines causée par R. solani sur des plants de fèves in vivo. Les deux traitements antagonistes ont considérablement réduit la gravité de la pourriture des racines.