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Graphene oxide (GO) is typically synthesized by graphite powder under strong oxidizing reaction, possessing with the same set of functional groups: epoxy and hydroxyl in basal plane and carboxyl and hydroxyl groups existence on the flake edges which endow GO with amphipathy. GO and its functionalized derivatives have been successfully tested in many domains, such as polymer composites, biosensors, drug delivery systems, etc. In this paper, GO was prepared by a modified Hummers method employing improved process (preparation and separation), aiming at industrialization with the lowest cost. Moreover, some novel functional groups with different properties were controlled chemically grafted onto GO to modify the wettability and reaction activity with other materials. The hydrophobicity and the thermal property of graphene oxide were enhanced by chemical functionalization.

The chemical composition of essential oil (1.18% yield) from celery seeds by hydrodistillation extraction method was analyzed by GC-MS. A total of 23 constituents were detected, in which 18 compounds that account for 91.38% were identified. The main constituents were limonene (31.15%), β-selinene (22.28%) , p-cresyl isovalerate (14.94%), α-2-propenylbenzenemethanol (9.872% ), β-myrcene (4.32%) and α-selinene (4.32%). The abilities of scavenging DPPH radical of the essential oil and hydrodistillation residue were studied. The result indicated that the maximum scavenging rates was 98.1% when 0.20 mL of the oil was used. The extracts of residue by methanol, ethanol and acetone also has remarkable scavenging activity. The result showed that the scavenging rates of the methanol, ethanol and acetone extracts of the residue were 91.5%, 91.2% and 56.2% respectively, when 0.10 mL of the extract solutions was used.

The essential oil (1.83% yield, w/w) of Amomum tsao-ko was obtained by hydrodistillation method in Clevenger apparatus. 38 constituents were detected in essential oil of Amomum tsao-ko by GC-MS analysis. 32 compounds representing 98.393% were identified, of which 1,8-cineole (40.891%), α-phellandrene (9.769%), 4-propyl-benzaldehyde (6.988%), and (E)-citral (4.949%) were major compounds. In particular, 1,8-cineole (48.03%) was quantified accurately by GC-FID using external standard method. As a reference to penicillin sodium, antibacterial activity of the essential oil and 1,8-cineole were evaluated against the bacteria and fungi using agar disc diffusion respectively. The order of antimicrobial activitiy of the essential oil against the bacteria was as follows: Bacillus subtilis.> Staphylicoccus albus.> Escherichia coli. The order of antimicrobial activity of the essential oil against the fungi was: Aspergillus oryzae> Rhizopus sp.> Penicillium sp.The 1,8-cineole showed weak inhibiting effect to the bacteria and ineffective against the fungi.

The essential oil was obtained from the white Basil (Ocimum basilicum L.) grown in Heilongjiang by hydrodistillation in a clevenger apparatus with 0.28% yield. Then the chemical composition of the essential oil was analyzed by GC-MS. A total of 25 constituents were detected, 24 compounds representing for 98.99% were identified, of which the most abundant compound was β-linalool (64.421%). The antibacterial activities of oil were tested against 3 different general of bacteria and were compared with that of the Penicillin sodium, using the filter paper disc agar diffusion method. The result showed that the oil has powerful inhibitory effects against Staphylicoccus albus, followed by Bacillus subtilis, Escherichia coli.

The essential oil (yield 1.46%, w/w) of Monarda citriodora flowers obtained by hydrodistillation was analysed by GC-MS, Totally 30 constituents were detected. 26 compounds representing 97.23% were identified, of which thymol (44.599%), 1,8-cineole (23.613%), α-phellandrene (4.815%) and β-cymene (4.019%) were major compounds. Thus, the monoterpenes and sesquiterpenes were the predominant portions of the oil. Antibacterial ability of Monarda citriodora essential oil was tested by disc agar diffusion against Escherichia coli, Bacillus subtilis, and Staphylicoccus albus. Antibacterial properties were compared to penicillin. Higher antibacterial activity was observed.