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Gavilea australis is a terrestrial orchid endemic from insular south Argentina and Chile. Meeting aspects of mycorrhizal fungi identity and compatibility in this orchid species is essential for propagation and conservation purposes. These knowledge represent also a first approach to elucidate the mycorrhizal specificity of this species. In order to evaluate both the mycorrhizal compatibility and the symbiotic seed germination of G. australis, we isolated and identified its root endophytic fungal strains as well as those from two sympatric species: Gavilea lutea and Codonorchis lessonii. In addition, we tested two other strains isolated from allopatric terrestrial orchid species from central Argentina. All fungal strains formed coilings and pelotons inside protocorms and promoted, at varying degrees, seed germination, and protocorm development until seedlings had two to three leaves. These results suggest a low mycorrhizal specificity of G. australis and contribute to a better knowledge of the biology of this orchid as well as of other sympatric Patagonian orchid species, all of them currently under serious risk of extinction.

The aim of the present study was to investigate the efficiency of the encapsulation-dehydration technique for cryopreservation of Cyrtopodium hastchbachii Pabst seeds. Immature seeds of this species were cryopreserved by an encapsulation-dehydration technique. Seeds of five immature pods, 120 days after pollination, were encapsulated in 3% calcium alginate matrix and pretreated in liquid medium supplemented with 0.08 M sucrose (24 h), 0.15 M sucrose (24 h), 0.25 M sucrose (48 h), 0.5 M sucrose (24 h) and 0.75 M sucrose (24 h) in shaker at 60 rpm. Alginate beads were dehydrated 5 h in silicagel and immersed in liquid nitrogen for 12 h. Cryopreserved beads were thawed at 30 degrees C for 1 min, rehydrated using the same liquid mediums [0.75 M sucrose (24 h), 0.5 M sucrose (24 h), 0.25 M sucrose (48 h) and 0.15 M sucrose (24 h)] and cultivated in half strength Murashige & Skoog medium (1962) with the addition of 2 g/L activated charcoal. Sixty four percent of seeds survived and developed into acclimatized plants after being cryopreserved. In this work, the encapsulation-dehydration technique was employed for first time in Cyrtopodium hatschbachii.

In this study, we evaluated the antibacterial activity of essential oil vapors against histamine-producing bacteria Morganella morganii NBRC3848 and Raultella planticola NBRC3317. We measured the minimum inhibitory dose (MID) of 14 essential oils towards these two strains. Allyl isothiocyanate (AIT) and salicylaldehyde (SA) vapors showed higher antibacterial activity than the other 12 essential oil vapors. Both AIT and SA vapors suppressed growth of total aerobic bacteria and histamine-producing bacteria in bigeye tuna and mackerel meat during storage at 12°C. These vapors also inhibited histamine accumulation in bigeye tuna meat and mackerel meat. Thus, application of AIT and SA vapors is effective for preventing increase of histamine-producing bacteria and histamine formation in fish meat.

The aim of this study is to examine whether various essential oils, food additives, peracetic acid and detergents inhibit bacterial histidine decarboxylase. Crude extract of Morganella morganii NBRC3848 was prepared and incubated with various agents. Histidine decarboxylase activity was significantly inhibited (p<0.05) by 26 of 45 compounds tested. Among the 26 agents, sodium hypochlorite completely decomposed both histidine and histamine, while peracetic acid caused slight decomposition. Histidine and histamine were stable in the presence of the other 24 agents. These results indicated that 25 of the agents examined were inhibitors of histidine decarboxylase.

We have investigated the control of halophilic histamine-producing bacteria, Photobacterium phosphoerum and Photobacterium damselae by using vapor of essential oils and other agents. Three of fourteen essential oils showed high antibacterial activity against histamine-producing bacteria. Among food additives and detergents, ten of twenty-one food additives and seven of nine detergents also showed antibacterial activity. Low concentrations of sodium chloride suppressed the growth of both species. We examined the resistance of these bacteria to dryness on food contact surfaces. After 0.5 hours, no viable cells were detected. So, the bacteria were sensitive to dry conditions. These results should contribute to development of the techniques to prevent histamine food poisoning.

We investigated the antibacterial activity of food additives and detergents against histamine-producing bacteria on food contact material surfaces. Based on minimum inhibitory concentration (MIC) testing with Morganella morganii NBRC3848, Raoultella planticola NBRC3317 and Enterobacter aerogenes NCTC10006, we screened nine food additives and four detergents with relatively high inhibitory potency. We prepared food contact material surfaces contaminated with histamine-producing bacteria, and dipped them into fourteen agents (100 µg/mL). Sodium hypochlorite, benzalkonium chloride, benzethonium chloride, n-hexadecyltrimethylammonium chloride and 1-n-hexadecylpyridinium chloride showed antibacterial activity against histamine-producing bacteria. We prepared low concentrations of the five agents (10 and 50 µg/mL) and tested them in the same way. Sodium hypochlorite showed high antibacterial activity at 10 µg/mL, and the other four showed activity at 50 µg/mL. So, washing the material surface with these reagents might be effective to prevent histamine food poisoning owing to bacterial contamination of food contact surfaces.

Encapsulation-dehydration was employed for cryopreserving seeds and in vitro-cultured protocorms of Oncidium bifolium. Freshly harvested seeds, 120 days after pollination, were encapsulated in beads containing 1/2 MS medium with 3% sucrose and 3% calcium alginate and subsequently pretreated in agitated (80 rpm) liquid medium supplemented with 0.15 M sucrose (24 h) followed by 0.25 M sucrose (48 h), 0.5 M sucrose (24 h) and 0.75 M sucrose (24 h). The beads with seeds were dehydrated with silica gel for 5 h to 19.2% moisture content and immersed in liquid nitrogen for 1 h, thawed at 30 degrees C for 2 min, post-treated using the same series of liquid media [0.5 M sucrose (24 h), 0.25 M sucrose (48 h), 0.15 M sucrose (24 h)], and recultured on 1/2 MS medium with 0.1M sucrose and 0.7% percent agar. As much as 4.8% of the cryopreserved seeds produced complete plants. In-vitro cultured protocorms were successfully cryopreserved following the same procedure, allowing 11.3% of them to produce plants.

Patients with various respiratory infections, primarily wet cases of bronchiectasis, were treated with lividomycin (LVDM) at a dose of 1 g/day for about a week. The results obtained are as follows: 1. Of the 15 patients with refractory bronchiectasis who had previously been treated with various other antibiotics, 11 patients (73.3%) responded to LVDM. Although there was no patient who responded to LVDM excellently, good cures were achieved in 5 pateints and fair cures in 6 patients. 2. In bronchiectasis patients having infections in association with pulmonary tuberculosis (mixed infections), LVDM did not show any remarkable effects, excepting that fair cures were achieved in 3 patients. 3. In the 7 patients with acute bronchopneumonia, excellent, good and fair cures were achieved in 1, 5 and 1 patient, respectively. Although LVDM was effective in all of the patients with the said infection, the number of the patients responded excellently was meager and the onset of action seemed to be somewhat slow. 4. In one patient with lobar pneumonia, LVDM was not effective. 5. The MIC values of LVDM for clinically isolated various organisms are summarized below: Pseudomonas aeruginosa 50 mcg/ml, Klebsiella pneumoniae 3.13 to 6.25 mcg/ml, Haemophilis influenzae 1.56 to 6.25 mcg/ml, Diplococcus pneumoniae 50 mcg/ml, alpha-Streptococcus 50 to 100 mcg/ml, beta-Streptococcus 100 mcg/ml, and Staphylococcus aureus 1.56 mcg/ml. 6. In spite of the fact that a majority of the patients participated in this study were the aged, LVDM's side effects were limited to an increase of BUN (one patient) and eruption (one patient). Any noticeable changes in hepatic and renal function, hearing acuity, etc. were not observed. As indicated above, LVDM was effective against, respiratory infections as well as infections of the urinary tract on which a considerable number of research has already been reported. Thus, it is considered to be worthwhile to use LVDM for the treatment of respiratory infections.