Bactérias e maçãs?

Sim. E sementes:
https://zap.aeiou.pt/maca-100-milhoes-bacterias-nao-pensa-269834

Citando:
""Escherichia-Shigella, um grupo de bactérias que inclui patógenos conhecidos, foi encontrado na maioria das amostras de maçãs convencionais, mas não em maçãs orgânicas. Para os Lactobacilli benéficos aconteceu o oposto“.

Além disso, “metilbactérias, conhecidas por melhorar a biossíntese de compostos com sabor a morango, foram significativamente mais abundantes em maçãs orgânicas, especialmente em amostras de casca e conteúdo, que em geral tinham uma microbiota mais diversa do que sementes, caule ou cálice”."

Microbioma e obesidade

https://www.diariodepernambuco.com.br/app/noticia/ciencia-e-saude/2019/05/10/internas_cienciaesaude,787301/cientistas-descobrem-em-micro-organismos-nova-esperanca-contra-a-obesi.shtml

Citando:
"
No estudo, os cientistas analisaram 22 pacientes com obesidade e que não apresentavam outros problemas de saúde comumente associados à enfermidade, como diabetes e doença hepática. Durante 12 semanas, metade dos participantes tomou cápsulas contendo matéria fecal de um doador magro, e o restante ingeriu cápsulas de placebo. Os pesquisadores procuravam detectar mudanças no hormônio intestinal chamado peptídeo tipo glucagon 1 (GLP1), que está ligado ao reflexo da saciedade — a sensação de ter comido o suficiente. Nos resultados iniciais, não observaram diferenças na perda de peso ou no hormônio GLP1.

Duas alterações na microbiota dos participantes, porém, chamaram a atenção: diminuição na quantidade de um ácido biliar relacionado a resistência à insulina e alterações nas amostras de fezes dos participantes — a composição ficou mais similar a do doador magro. Essas alterações, segundo os cientistas, apontam para a possibilidade de gerar intervenções metabólicas ao manipular a microbiota humana. “Nosso estudo adiciona um primeiro passo encorajador na tentativa de entender o papel do microbioma intestinal em pessoas metabolicamente saudáveis com obesidade. Esperamos que isso sirva para terapias mais direcionadas no futuro”, ressalta Allegretti."

Bactérias no intestino associadas a sucesso nas dietas

(ou falhas):
https://text.npr.org/s.php?sId=635362706

Citando:
"New research suggests the mix of microbes in our guts can either help — or hinder — weight-loss efforts.

"We started with the premise that people have different microbial make-ups, and this could influence how well they do with dieting," explains Purna Kashyap, a gastroenterologist at the Mayo Clinic in Rochester, Minn.

As part of the study, Kashyap and his collaborators tracked the progress of people who were enrolled in a lifestyle-intervention program for weight loss. The participants were advised to follow a low-calorie diet, and they were tracked closely for about three months.

"We found that people who lost at least 5 percent of their body weight had a different gut bacteria as compared to those who did not lose 5 percent of their body weight," Kashyap explains. Their findings are published in the journal Mayo Clinic Proceedings."

(...)

"The successful dieters had an increased abundance of a bacteria called Phascolarctobacterium, whereas another bacteria, Dialister, was associated with a failure to lose the weight. And, Kashyap says it's likely that there are other types of bacteria that might influence dieting as well." 

Bottom line: the bacteria eat what else can't

"Probiotics that are currently on the market would not be effective. The idea is to develop a new product that includes the specific types of bacteria linked to successful dieting.

But it's not so simple to manipulate the mix of microbes in our guts. Identifying the organism — or organisms — that are thought to be beneficial is just the first step."

Finalidade do apêndice começa a ser compreendida

O apêndice, afinal parece ter uma finalidade (de acumulação de uma reserva de partes do microbioma):
Why do we have an appendix? — Quartz

A Gut Makeover for the New Year - The New York Times

Continuam os estudos do microbioma intestinal ("bicharada" no intestino) e pistas que indiciam que podemos alterá-lo com a alimentação (beneficiando a nossa saúde):

A Gut Makeover for the New Year - The New York Times

Citando:
"If you’re making resolutions for a healthier new year, consider a gut makeover. Refashioning the community of bacteria and other microbes living in your intestinal tract, collectively known as the gut microbiome, could be a good long-term investment in your health.

Trillions of microbial cells inhabit the human body, outnumbering human cells by 10 to one according to some estimates, and growing evidence suggests that the rich array of intestinal microbiota helps us process nutrients in the foods we eat, bolsters the immune system and does all sorts of odd jobs that promote sound health. A diminished microbial ecosystem, on the other hand, is believed to have consequences that extend far beyond the intestinal tract, affecting everything from allergies and inflammation, metabolic diseases like diabetes and obesity, even mental health conditions like depression and anxiety.

Much of the composition of the microbiome is established early in life, shaped by forces like your genetics and whether you were breast-fed or bottle-fed. Microbial diversity may be further undermined by the typical high-calorie American diet, rich in sugar, meats and processed foods. But a new study in mice and people adds to evidence that suggests you can take steps to enrich your gut microbiota. Changing your diet to one containing a variety of plant-based foods, the new research suggests, may be crucial to achieving a healthier microbiome."

PS. Mais vale seguir esta recomendação do que optar pelas alternativas que se começam a falar: Os transplantes de... matéria fecal (arghhh).

Cold-weather friends | The Economist

Mais coisas interessantes sobre o microbioma (parte do intestino):

Cold-weather friends | The Economist

Quoting: 

"If a study by Mirko Trajkovski of the University of Geneva is correct, for your gut bacteria to remodel your intestines and make them better at absorbing nutrients before the blizzards arrive. Dr Trajkovski’s work, just published in Cell, was on mice. But previous experience suggests that in this area of biology what applies to mice applies to men as well. If that is true in this case too, it will mean an important part of the human body’s thermoregulation is actually controlled by its companion microbes."