Photosynthesis

In the search for antitumor compounds from Bipolaris oryzae, the coexistence of ophiobolins and cochlioquinones is reported for the first time. Of the compounds isolated, anhydrocochlioquinone A (7) was identified as a new antitumor agent. The structure of 7 was fully characterized by spectroscopic data, including COSY, HSQC, HMBC, and NOESY. The cytotoxicity of isolated compounds against HeLa and KB cells is also described. [DOI: 10.1016/j.tetlet.2007.05.151]

[1]. Isolation of Ophiobolin A and Its Analogs as Inhibitors to Photosynthesis.

Anhydrous snake venom A is a sesquiterpene compound. It has been reported that anhydrous snake venom A exists in Bipolaris maydis and Bipolaris oryzae, with relevant data reported. Snake venom and spiroquinone are key fungal phytotoxins associated with serious diseases in cereal crops. They are released during infection by Bipolaris spp. and other related genera such as Stachybotrys, Helminthosporium, and Cochliobolus. Snake venom has broad inhibitory effects on nematodes, fungi, and bacteria, including inducing apoptosis in the L1210 cell line. Spiroquinone has been reported to have anti-angiogenic activity and is an antagonist of the human chemokine receptor CCR5, a key target in current anti-HIV-1 therapies. Although the mechanisms of these activities are poorly understood, these findings suggest the potential of serpentin and trichoquinone for biological and pharmaceutical applications. As part of our ongoing search for antitumor lead compounds from medicinal plants and microorganisms, we investigated the inhibitory effects of Diplosporium oryzae extract on human cancer cell lines. Through bioactivity-directed fractionation of the ethyl acetate extract, we isolated a novel compound, dehydrated trichoquinone A (7), along with the known serpentin (1–4) and trichoquinone (5–6). Furthermore, this paper reports the first coexistence of serpentin and trichoquinone. Diplosporium oryzae strain AGR006-2004 was isolated from rice leaves infected with brown spot disease in an experimental field at Kasetsart University, Thailand. The fungus was cultured in MG broth, which yielded the highest extract yield among the media used in this experiment. Compound 7 is the first cochlear quinone compound found to contain a dehydropyranobenzoquinone residue. To our knowledge, only a few natural products currently contain dehydropyranobenzoquinone, including isopigment J, floridone, and gallopiperidone. From a biosynthetic perspective, Canonica proposed that the formation of cochlequinone compounds is achieved by introducing a farnesyl unit into an aromatic precursor, the secondary methyl group (C-27 and C-28) of which is derived from methionine. The dehydration reaction of 12-OH in cochlequinone A yields compound 7. Notably, this study is also the first to report the coexistence of snake toxin and cochlequinone compounds in Diplosporium species. All isolated compounds were subjected to in vitro cytotoxicity studies against human cervical cancer cells (HeLa) and human oral epidermal cancer cells (KB) using the standard MTT assay (Table 2). Snake toxin I (2) showed high cytotoxicity against HeLa and KB cells, with IC50 values of 0.1 and 0.9 μg/mL, respectively, while dehydrated cochlequinone A (7) showed only moderate activity against HeLa cells (IC50 of 5.9 μg/mL). Previous studies on the antitumor activity of cochlequinones have shown that they inhibit tumor invasion through different targets. Cochlequinone A potently inhibits diacylglycerol kinase, a key enzyme in melanoma cell apoptosis. On the other hand, cochlequinone A1 exhibits anti-angiogenic activity by effectively inhibiting the formation of tubular structures in endothelial cells. However, the weak cytotoxicity of cochlequinones suggests that they are most likely to inhibit cancer cell proliferation through anti-angiogenesis or induction of apoptosis. The tumor-suppressive mechanism of dehydrated cochlequinone A (7) is currently being investigated in our laboratory. [https://www.sciencedirect.com/science/article/pii/S0040403907010465?via%3Dihub]

C25H34O3

382.5357

382.251

C, 78.49; H, 8.96; O, 12.55

6026-65-9

Anhydro-6-epiophiobolin A;90411-20-4

12306827

Typically exists as solid at room temperature

5.213

0

3

2

28

784

7

O1[C@@H](/C=C(\C)/C)C[C@H](C)[C@@]21CC[C@]1(C)C[C@]3([H])C(C)=CC([C@]3([H])C(C=O)=CC[C@@]21[H])=O |c:27|

MDYSLOGZXCWLSL-CWPAWFJGSA-N

InChI=1S/C25H34O3/c1-15(2)10-19-12-17(4)25(28-19)9-8-24(5)13-20-16(3)11-21(27)23(20)18(14-26)6-7-22(24)25/h6,10-11,14,17,19-20,22-23H,7-9,12-13H2,1-5H3/b18-6-/t17-,19-,20+,22+,23+,24+,25-/m0/s1

(1'R,2S,3S,3'S,5R,7'S,8'E,11'R)-1',3,4'-trimethyl-5-(2-methylprop-1-enyl)-6'-oxospiro[oxolane-2,12'-tricyclo[9.3.0.03,7]tetradeca-4,8-diene]-8'-carbaldehyde

Anhydroophiobolin A; 6026-65-9; (1'R,2S,3S,3'S,5R,7'S,8'E,11'R)-1',3,4'-trimethyl-5-(2-methylprop-1-enyl)-6'-oxospiro[oxolane-2,12'-tricyclo[9.3.0.03,7]tetradeca-4,8-diene]-8'-carbaldehyde; (18R)-5-Oxo-14,18-epoxy-3,4-didehydroophiobola-7,19-diene-25-al; (1'R,2S,3S,3'S,5R,7'S,8'E,11'R)-1',3,4'-trimethyl-5-(2-methylprop-1-enyl)-6'-oxospiro(oxolane-2,12'-tricyclo(9.3.0.03,7)tetradeca-4,8-diene)-8'-carbaldehyde; CHEMBL2393052;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)