Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of Vietnam.The yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identification of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the oils.In EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant monoterpenes.Sabinene appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present study.These databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

Himalomycin A and cycloheximide-producing marine actinomycete from Lagos Lagoon soil sediment

Objective:To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for antibiotic production.Methods:Soil samples were collected from four different locations of Lagos Lagoon and were dried for 2 weeks.Actinomycetes were isolated by serial dilution using spread plate method on starch casein and Kuster’s agar supplemented with 80μg/mL cycloheximide to prevent fungal growth.The plates were incubated at 28°C for 1-2 weeks.Isolates were selected based on their cultural characteristics as well as their Gram’s reaction and subcultured on same media for isolation and incubated at 28°C for 3 days.Pure cultures were maintained on nutrient agar slants at 4°C.Thereafter,they were inoculated into starch casein and Kuster’s broth media and incubated at 28°C for 8 days.The resulting crude extracts were screened for antimicrobial activity against the following microorganisms:methicillin resistant Staphylococcus aureus,Staphylococcus aureus ATCC 29213,Escherichia coli ATCC 29522,Pseudomonas aeruginosa ATCC 27853,Candida albicans and Enterococcus faecalis ATCC 29212.Coagulase-negative staphylococci isolated from HIV patients were also used(Staphylococcus warneri,Staphylococcus xylosus and Staphylococcus epidermidis).Extraction of secondary metabolites was carried out and analysed using gas chromatography-mass spectrometer.Results:All the isolates displayed varying antimicrobial activity against at least one of the test organisms.Himalomycin A was identified in the extract from isolate ULS7.The gas chromatography-mass spectrometer data analysis showed the antibiotic profile of these isolates.Conclusions:The isolate ULS7 was found to display the highest antimicrobial activity against the test organisms.