Insect growth regulatory activity of Vitex trifolia and Vitex agnus-castus essential oils against Spilosoma obliqua

Essential oils of Vitex trifolia and Vitex agnus-castus were evaluated against Vth instar larvae of Spilosoma obliqua, when applied topically on the dorsal side of mesothoracic region, for insect growth regulatory activity. This treatment caused extended larval period and pupal period, increase in larval mortality and adult deformity and decrease in adult emergence, fecundity of female and egg fertility of test insect.     

Insecticidal activity of some essential oils against larvae of Spodoptera littoralis

Thirty-four essential oils were tested for insecticidal activity (fumigation or topical application) against larvae Spodoptera littoralis. Twenty essential oils applied by fumigation were highly toxic to the third instar of S. littoralis larvae. Two essential oils Nepeta cataria and Thuja occidentalis were highly toxic, with LC50< or =10.0 ml/m3. Five essential oils Salvia sclarea, Thymus mastichina, Origanum majorana, Pogostemon cablin and Mentha pulegium were toxic with LC50 between 10.1 and 20.0 l ml/m3. Twenty-three essential oils were highly toxic to the third instar of S. littoralis larvae after topical application. Eight essential oils Mentha citrata, N. cataria, S. sclarea, O. vulgare, O. compactum, Melissa officinalis, T. mastichina, and Lavandula angustifolia were highly toxic with LD50 < or =0.05 microl/larvae.     

Antiparasitic antioxidant phenylpropanoids and iridoid glycosides from Tecoma mollis

A radical scavenging guided phytochemical study on the stem bark of Tecoma mollis afforded seven active phenylpropanoid glycosides (1–7), including a new one (4), and one iridoid (8). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (1–7) displayed promising antioxidant activity (DPPH assay) in relation to ascorbic acid (positive control). The antimicrobial activity for compounds (1–8) was evaluated against five bacterial and five fungal strains. The isolated compounds exhibited nonselective weak to moderate antimicrobial activity. The highest antileishmanial activity against Leishmania donovani was observed for compound (7) with an IC₅₀ value of 6.71 μg/ml, using pentamidine and amphotericin B as drug controls. Compound (5) exhibited moderate antimalarial activity (45% inhibition) against chloroquine sensitive (D6) clones of Plasmodium falciparum.     

Insecticidal activity of certain medicinal plants

The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)].     

Sesquiterpenoids and norterpenoids from Vitex negundo

Chemical investigation on the seeds of Vitex negundo has afforded a new furan-containing sesquiterpenoid, negunfurol (1), a new norlabdane-type diterpenoid, negundoal (2), and two new norursane-type triterpenoids, negundonorins A (3) and B (4), together with two know compounds, 3-formyl-4,5-dimethyl-8-oxo-5H-6,7-dihydronaphtho[2,3-b]furan (5) and 3-epi-corosolic acid (6). Their structures and configurations were elucidated by detailed spectroscopic analyses on the basis of NMR, IR, and MS data. Compound 3 was strongly cytotoxic against ZR-75-30 cell line with IC₅₀ value of 0.56 ± 0.19 μg/mL, whereas compound 1 was most active against HL-60 cell line with IC₅₀ value of 0.94 ± 0.26 μg/mL.     

Insecticidal action of the polyphenolic rich fractions from the stem bark of Streblus asper on Dysdercus cingulatus

Extracts from the stem bark of Streblus asper possess insecticidal activity against the fifth instar of Dysdercus cingulatus. Methanolic extract showed an LC(50) value of 5.56 microg/insect. Partition with chloroform increased the insecticidal activity (LC(50) 2.01 microg/insect). Three polyphenolic rich fractions were obtained from silica-gel column chromatography of the chloroform fraction and found to have noteworthy insecticidal activity (LC(50): 1.82 microg, 2.70 microg, 2.26 microg/insect) by topical application. This may provide a useful beginning for the development of biopesticides.     

Phytoconstituents from Vitex agnus-castus fruits

A new labdane-diterpene, viteagnusin I (1), together with 23 known phytoconstituents were isolated from the fruits of Vitex agnus-castus L, and their structures characterized by spectroscopic methods (NMR and MS). The known compounds include ten flavonoids, five terpenoids, three neolignans, and four phenolic compounds, as well as one glyceride. Biological evaluation identified apigenin, 3-methylkaempferol, luteolin, and casticin as weak ligands of delta and mu opioid receptors, exhibiting dose-dependent receptor binding.     

Biological activity of Schinus molle on Triatoma infestans

Hexanic extracts from leaves and fruits of Schinus molle were tested for repellent and insecticidal properties against first instar nymphs and eggs of Triatoma infestans, the vector of Chagas' disease. Leaf and fruit extracts were highly repellent for first nymphs. Fruit extracts had also ovicidal activity.     

Antimicrobial activity of Diospyros anisandra

Leaves, root and stem bark of Diospyros anisandra were screened against two strains of Mycobacterium tuberculosis, one resistant and one susceptible to antibiotics, using the microplate Alamar blue assay test. The lypophylic fractions of the root and bark showed significant inhibitory activity against both strains, with the hexane fraction of the bark showing the strongest activity (MIC 6.25 microg/ml) against the resistant strain and a significant antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans, Aspergillus niger, and Colletotrichum gloeosporioides. The bioassay-guided purification of the bioactive hexane fraction resulted in the isolation and identification of the naphthoquinone plumbagin as one of the metabolites responsible for the biological activity.     

Antimicrobial activity of Hedychium spicatum

Extracts from rhizomes of Hedychium spicatum were tested for their antibacterial and antifungal activity. Essential oil, petroleum ether and chloroform extracts showed inhibitory activity against Gram (+) and Gram (-) bacterial cultures, including a strain of methicillin and vancomycin resistant Staphylococcus aureus and fungal cultures.     

Screening of antioxidant activity of three Euphorbia species from Turkey

Euphorbia acanthothamnos, E. macroclada and E. rigida were investigated for their antioxidant activity. The antioxidant potential of extracts of E. acanthothamnos, E. macroclada and E. rigida was evaluated using different complementary antioxidant tests.     

Evaluation of antimicrobial activity of Cleome viscosa and Gmelina asiatica

The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi.     

Antibacterial activity of Abies webbiana

The methanol extract of the dried leaves of Abies webbiana was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.     

Antioxidant activity of Punica granatum fruits

Arils, juice and rinds of Punica granatum fruits and their aqueous and ethyl acetate extracts displayed good antioxidant activity.     

Antimicrobial activity of Caesalpinia pulcherrima, Euphorbia hirta and Asystasia gangeticum

The ethanolic extracts of the dry fruits of Caesalpinia pulcherrima, aerial parts of Euphorbia hirta and flowers of Asystasia gangeticum were tested for antimicrobial activity. The three plants exhibited a broad spectrum of antimicrobial activity, particularly against Escherichia coli (enteropathogen), Proteus vulgaris, Pseudomonas aeruginosa and Staphylococcus aureus.     

Antibacterial activity of Leonurus sibiricus aerial parts

Different solvent extracts (carbon tetrachloride, chloroform, acetone and methanol) of Leonurus sibiricus were studied for their antibacterial activity. Carbon tetrachloride and chloroform extracts showed a broad spectrum of antibacterial activity.     

Antioxidant activity of Maytenus ilicifolia root bark

Maytenus ilicifolia is an important plant with potential on cancer treatment and has been largely used in Brazil and other countries. We have evaluated the crude ethanolic extract of M. ilicifolia as a potential antioxidant source using an assay based on the bleaching of the radical monocation 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(*+)) and by HOCl scavenger capacity. Trolox and uric acid were used as positive controls. The results indicated M. ilicifolia root bark as a great source of antioxidants based on its potential as scavenger of radicals.     

Antibacterial activity of plant extracts from Brazilian southeast region

A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus.     

Antimicrobial activity of the Derris elliptica, Derris indica and Derris trifoliata extractives

Various parts of Derris elliptica, Derris indica and Derris trifoliata on fractionation with a number of solvents (petrol, dichloromethane, ethyl acetate, butanol and methanol) gave fractions which demonstrated a varied level of broad spectrum antibacterial activity. Good activity was exhibited by the methanol fractions of the leaves and root heart-wood, petrol, butanol and methanol fractions of the root bark of D. indica and petrol and ethyl acetate fractions of D. trifoliata. None of the plants showed antifungal activity.     

Anti-ulcerogenic activity of the aerial parts of Lithraea molleoides

The hydro-alcoholic extract of the aerial parts of Lithraea molleoides, given orally at a dose of 1000 mg/kg, showed significant anti-ulcerogenic activity on ulcer induced by indomethacin and absolute alcohol in rats.