A Natural Solution for California's Herds: African Catfish Peptides

California's cattle producers and agricultural communities are all too familiar with the rising challenge of antibiotic resistance, making common bacterial infections harder to treat in livestock. But imagine a future where we could tackle these infections with a natural, powerful alternative. Our research points to just that: antimicrobial peptides (AMPs) found in African catfish.

We're really excited about these peptides because African catfish thrive in pathogen-rich freshwater, naturally producing these robust immune compounds in their skin mucus as a defense. This natural origin makes them highly appealing alternatives to synthetic drugs.

Predicted Safety and Potent Action

One of the most compelling aspects of these AMPs is their predicted safety for mammals. Our initial computer analyses suggest that various catfish AMPs are generally recognized as safe (GRAS). We predict they'll be absorbed in the human intestine without causing liver, brain, or heart toxicity. Furthermore, lab tests on a promising peptide, NACAP-II, confirmed it was non-hemolytic, meaning it didn't damage rabbit red blood cells—a strong indicator of its potential safety for mammalian cells.

Beyond safety, these peptides demonstrate effectiveness against problematic bacteria. One study revealed NACAP-II's strong activity against Extended-Spectrum Beta-Lactamase (ESBL)-producing Escherichia coli—a critical concern for both animal and human health due to its resistance to many common antibiotics. Another peptide, ACAP-IV, also showed antibacterial activity against E. coli and Staphylococcus aureus. We believe these AMPs work by directly disrupting bacterial cell membranes, a mechanism that makes it harder for bacteria to develop resistance compared to how they resist traditional antibiotics.

Fruit Report: Page

Arsenic (As)

Peach trees are very sensitive to arsenic toxicity. The disorder has been found in several peach and nectarine orchards in the San Joaquin Valley. The toxicity is often caused by past use of arsenic based pesticides and herbicides, especially where grape vineyards were previously planted.
View Page
Fruit Report: Page

Sand Tanks

In 1999 we obtained 60 large (11' x 8' x 4' deep) plastic tanks and buried them in the ground at Kearney. We filled them with clean sand and planted a Zee Lady peach, Grand Pearl nectarine and Fortune plum in each.
View Page
Fruit Report: Page

Calcium (Ca)

Calcium deficiency has never been identified in California peach orchards. Most soils in the San Joaquin Valley are abundantly supplied with Ca and leaf samples generally show levels well above the deficiency threshold (1.0%).
View Page
Fruit Report: Page

Zinc Studies with Seedlings

Using Nemaguard seedlings growing in sand, we conducted a series of experiments comparing different zinc formulations. The seedlings were grown with a nutrient solution containing no zinc until deficiency symptoms were observed.
View Page
Fruit Report: Page

Foliar Urea

We have conducted research to show that foliar urea sprays in the fall can contribute to the total nitrogen needs of a peach or nectarine tree.
View Page
Fruit Report: Page

Zinc (Zn)

Zinc deficiency is common in peach, plum and nectarine orchards in the San Joaquin Valley. Generally, it is a rootstock problem as typical orchard soils are not deficient, but Nemaguard is a poor forager for this nutrient. Some other rootstocks do not exhibit the same problem.
View Page
Fruit Report: Page

Dormant Sampling

We have several year's experience with a dormant season procedure for sampling shoots. There are still many details to work out, but it appears to show promise for some nutrients.
View Page
Fruit Report: Page

Phosphorus (P)

Phosphorus is an important nutrient in all plants as it is required for membranes, energy molecules and nucleic acids. However, it is seldom deficient in stone fruit trees in California.
View Page
Fruit Report: Page

Sulfur (S)

Sulfur deficiency has never been documented in California stone fruit orchards. This is probably because S is found in many fertilizers and is abundant in most soils. In addition, it is found in the atmosphere and is carried into the soil by rain.
View Page
Fruit Report: Page

Copper (Cu)

Copper deficiency is rare in California stone fruit orchards but has been observed in plums growing on Nemaguard rootstock. Symptoms include shoot dieback and formation of small, chlorotic and malformed young leaves. Rough bark accompanied by gumming also occurs.
View Page