All bioassays were conducted using the horn fly (Haematobia irritans irritans). p-Anisaldehyde (98% purity) was diluted in acetone for all experiments. Acetone alone served as the solvent control.
Egg Mortality Assay: Filter paper discs were wetted with 100 µl of p-anisaldehyde dilutions (0.00003% and 0.00001%), dried, then moistened with deionized water. Twenty-five horn fly eggs were placed on each disc in a Petri dish and stored for 24 h at 27°C, 50% RH, 12:12 L:D. Hatched eggs were counted. [1]
Adult Contact Immobilization and Mortality Assay: p-Anisaldehyde was diluted to concentrations from 0.125% to 10%. Groups of 25 temporarily chilled adult flies were placed on filter paper in a Petri dish. Each group was sprayed through a funnel with 0.92 ml of the test solution. Flies were then transferred to ventilated cages. Numbers of immobilized (unable to walk/fly) and dead flies were recorded at intervals from 5 min to 4 h post-treatment. [1]
Effects on Development (Egg to Adult): p-Anisaldehyde was mixed with acetone and homogenized with fresh cow manure to achieve final concentrations of 1000, 5000, 10,000, and 20,000 ppm in the manure. Batches of 50 horn fly eggs were placed on the treated manure in cups and held for 1 week at 27°C, 50% RH, 12:12 L:D to allow larval development and pupation. Pupae were counted. Pupae were then transferred to Petri dishes, and emerged adults were counted a week later. [1]
Repellency and Toxicity by Fumigation: Static air olfactometer tubes were used. One end was sealed with a Petri dish containing a filter paper disc treated with 1 ml of p-anisaldehyde dilution (0.075% to 1.5%) and allowed to dry. The other end had an untreated filter paper. Twenty-five adult flies were released into the tube. Fly location (treated vs. untreated half), immobilization, and mortality were recorded at intervals from 5 min to 4 h. [1]
Feeding Deterrence Assay: Cotton cloth rectangles were saturated with 0.5 ml of p-anisaldehyde dilutions (0.3% to 10%) and dried. A blood-soaked cotton pad was covered with this treated cloth (forming a penetrable barrier). Five unfed adult flies were released into a ventilated cage with the blood pad assembly placed on top. The number of flies resting on the cloth (attempting to feed) versus at the cage bottom was recorded at intervals over 120 min. [1]
Sublethal Effects on Fecundity and Egg Hatchability: Groups of flies (1 female, 5 males) were sprayed inside a Petri dish setup with 1.6 ml of p-anisaldehyde dilutions (0.06% to 1%). Treated flies were individually housed in mesh-ended tubes. Flies were allowed to feed on a blood pad and oviposit onto a moist cotton cloth below the cage over 24h. Eggs were counted and hatchability assessed 40 hours later. [1]

Metabolism / Metabolites
Anisaldehyde undergoes slight demethylation, with the aldehyde group oxidized to an acid group. The main metabolite is anisic acid.

Toxicity Summary
Identification and Uses: p-Anisaldehyde is an oily liquid. It is used in perfumes and soaps, and also in organic synthesis. It is also an intermediate in many industrial processes. Human Studies: A 48-hour closed patch test in human subjects at a 10% concentration in petrolatum solution showed no irritation. A maximum dose test was conducted on 25 volunteers. No sensitization was observed when the substance was tested at a 10% concentration in petrolatum solution. p-Anisaldehyde showed a positive reaction for sister chromatid exchange in human lymphocyte oocytes in vitro, but not in Chinese hamster ovary (CHO) cells. Animal Studies: In a combined oral repeated-dose/reproductive/developmental toxicity screening test in rats, the 100 mg/kg/day dose group showed decreased body weight, thrombocytopenia, and hepatocyte hypertrophy. In reproductive studies, the 500 mg/kg/day dose group showed a significant decrease in fertility index, litter size, parturition index, and live birth count. This compound was not mutagenic to bacteria, but showed mutagenicity in mouse lymphoma cells in vitro.

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Interactions
Studies have shown that aromatic aldehydes may reduce cytochrome c. Therefore, this study investigated the interactions of aromatic aldehydes, including p-anisaldehyde, benzaldehyde, p-tolualdehyde, p-carboxybenzaldehyde, p-chlorobenzaldehyde, and p-nitrobenzaldehyde, with rat liver mitochondria in vitro. Although aromatic aldehydes (0.5–1.0 mM) inhibited pyruvate/malate and succinate-mediated respiration, as well as respiration mediated by other citrate cycle intermediates, aromatic aldehydes (1.0–20 mM) did not inhibit cytochrome c oxidase. Benzaldehyde (2–20 mM) significantly inhibited succinate dehydrogenase and ADP- and DNP-stimulated respiration. Since aromatic aldehydes inhibit pyruvate/malate and succinate-mediated respiration but not cytochrome c oxidase, multiple inhibitory sites are likely present, possibly located at substrate transport sites and active enzyme sites. Benzaldehyde (300 μM) inhibited pyruvate/malate-mediated state 3 respiration by up to 50%, suggesting that these inhibitions do not require additional functional groups or metabolism to other species.

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Non-human toxicity values
Oral LD50 in rats: 1510 mg/kg
Oral LD50 in guinea pigs: 1260 mg/kg
Dermal LD50 in rabbits: >5 g/kg

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For adult horneridians, the LD₅₀ and LD₉₀ of anisaldehyde were determined at multiple time points. At 30 minutes, the LD₅₀ was 4.632% and the LD₉₀ was 6.632%. These values decreased over time; after 4 hours, LD₅₀ was 1.652% and LD₉₀ was 3.127%. [1]
In fumigation bioassays, in a closed space, the use of 0.75% anisaldehyde resulted in the complete death (100%) of adult hornflies within 3-4 hours. [1]

[1]. Effects of the Botanical Compound p-Anisaldehyde on Horn Fly (Diptera: Muscidae) Repellency, Mortality, and Reproduction. J Med Entomol. 2018 Jan 10;55(1):183-192.

p-Methoxybenzaldehyde is a benzaldehyde compound with a methoxy substituent at the 4-position of the benzaldehyde molecule. It has multiple functions, including as an insect repellent, a human urine metabolite, a plant metabolite, and a bacterial metabolite. It has been reported in Inonotus juniperinus, Pseudomonas Hamiltonii, and other organisms with relevant data. See also: Anise oil (partial components). 4-Methoxybenzaldehyde (p-anisaldehyde) is a naturally occurring aromatic phenolic compound found in various plants. This study aims to explore its potential as a plant pest control tool for controlling hornflies. [1]
This compound has multiple effects on hornflies: extremely low concentrations (≤0.00003%) can cause egg death; concentrations ≥1000 ppm can inhibit the development of larvae in feces; direct contact and fumigation can paralyze and kill adults; concentrations ≥0.6% can strongly inhibit their feeding. [1]
Studies have found that fumigation has a mortality rate of about 12.5 times that of sprayed droplets on adult hornflies. In this study, sublethal concentrations had no significant effect on fertility or egg hatching rate. [1]
This compound is considered to be a neurotoxin, and fumigation can cause adult hornfly defecation and rumination, which may be related to its toxic effects. [1]

C8H8O2

136.1479

136.052

123-11-5

4-Methoxybenzaldehyde-d1;19486-71-6;4-Methoxybenzaldehyde-d3;342611-04-5

31244

Colorless to light yellow liquid

1.121

248-249 ºC

-1 °C

116 ºC

0.0±0.5 mmHg at 25°C

1.571-1.574

1.7

0

2

2

10

104

0

O(C([H])([H])[H])C1C([H])=C([H])C(C([H])=O)=C([H])C=1[H]

ZRSNZINYAWTAHE-UHFFFAOYSA-N

InChI=1S/C8H8O2/c1-10-8-4-2-7(6-9)3-5-8/h2-6H,1H3

4-methoxybenzaldehyde

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.

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

DMSO : ~100 mg/mL (~734.48 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (18.36 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (18.36 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (18.36 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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